Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.

com

State of the Art

Diagnosis and treatment of anterior knee pain

Vicente Sanchis-Alfonso,1 Jenny McConnell,2 Joan Carles Monllau,3 John P Fulkerson4
1
Department of Orthopaedic ABSTRACT that compromises an individual’s ability to perform
Surgery, Hospital Arnau de Anterior knee pain (AKP) is one of the most frequent an activity within the range considered normal’.
Vilanova and Hospital 9 de
Octubre, Valencia, Spain
reasons for adolescents and young adults to seek Such limitations may impose a change in a patient’s
2
McConnell Physiotherapy consultation for knee conditions. Owing to the complex lifestyle. Since AKP frequently occurs in young
Group, Centre for Sports multifactorial aetiology of AKP, with local, proximal and working adults, it has an important societal impact
Medicine Research and distal factors potentially involved, its treatment is due to work absences and lost productivity as well
Education, University of particularly difficult and challenging for the practitioner. as the economic expense involving in treating these
Melbourne, Melbourne,
Victoria, Australia A careful history and physical examination are crucial for patients.8 AKP is frequently met with a lack of
3
Department of Orthopaedic an accurate diagnosis and therefore a correct treatment. understanding within a patient’s circle of acquaint-
Surgery and Traumatology, The entire lower extremity should be examined, with ance, which worsens the psychological affectation.
Hospital del Mar, Universitat findings complemented by imaging studies to arrive at a Moreover, patients with AKP may also have an
Autònoma de Barcelona,
Barcelona, Spain
diagnosis. Arriving at a precise diagnosis is the increased risk of developing patellofemoral osteo-
4
Department of Orthopaedic cornerstone of developing an appropriate treatment. arthritis (PFOA).9 In summary, AKP has a negative
Surgery, Orthopedic Associates Given that the aetiology of AKP is multifactorial, impact on patients’ quality of life. As an indicator
of Hartford; University of individualised treatment must be tailored to the patient. of the importance of this clinical entity, the
Connecticut Medical School, Early intervention is very important to maximise the Chartered Society of Physiotherapy in the UK has
Farmington, Connecticut, USA
chance of a good prognosis. Non-surgical management ranked AKP as the third most important topic out
Correspondence to is effective in the majority of patients. Surgery is of 185 listed in their Musculoskeletal Research
Dr Vicente Sanchis-Alfonso, indicated solely in cases with pain that is refractory to Priority Project.10
Department of Orthopaedic non-operative treatment and well-defined structural The goal of this paper is to analyse in detail how
Surgery, Hospital Arnau de
Vilanova and Hospital 9 de abnormalities that are deemed to be the cause of the to better reach a diagnosis and therefore identify
Octubre, Avd Cardenal AKP can be targeted for repair or correction. the most suitable treatment in individual cases. We
Benlloch 36, 23, Valencia emphasise that the aetiology of AKP is multifactor-
46021, Spain; vicente.sanchis. ial, involving local, proximal and distal factors,
alfonso@gmail.com
BACKGROUND, PREVALENCE, AND SOCIETAL which leads to there being many subsets of patients
Received 30 December 2015 IMPACT with AKP. Hence, there is no single treatment.
Revised 23 February 2016 Anterior knee pain (AKP) is one of the most fre- Treatment has to be tailored to the individual
Accepted 2 March 2016 patient. In box 1, we outline 10 articles that the
Published Online First quent reasons for consultation in the context of
knee conditions in adolescent and young adult authors of this paper found to be key in the devel-
22 March 2016
patients, accounting for up to 74% of knee pain opment of evaluation and treatment of AKP.
experienced by adolescents participating in sports.1
Nejati et al2 found the prevalence rate of AKP to DIAGNOSIS
be 16.7% in a study performed in a sports medi- The patient’s clinical history and physical examin-
cine clinic. This rate was similar to that shown by ation are of paramount importance in diagnosing
Boling et al3 in a study that involved participants the cause of AKP. The physical examination is com-
from the US Naval Academy. Boling et al3 found a plemented by imaging studies, and the combination
prevalence of 15% in females and 12% in males. should yield a precise diagnosis that will be the
They also observed that the annual incidence of cornerstone in developing an appropriate thera-
AKP was 33 of 1000 people in female patients, but peutic programme. It must be emphasised that the
only 15 of 1000 people in male patients. Gender is cause of AKP should be a diagnosis of exclusion.
a significant predictor for the development of AKP,
with females having an incidence that is 2.23 times History
higher than that of males.3 However, the incidence First, a complete history of the patient’s symptoms
of AKP in the general population is unknown. is required to diagnose. We must listen to the
Treating patients with AKP is often frustrating, patient carefully. In any pathological entity, listen-
both for the orthopaedic surgeon and for the ing to the patient is essential, but in the one we
physiotherapist. Collins et al4 have shown 40% of deal with in this paper, it is even more important.
unfavourable recovery at 12 months after the initial The main symptom experienced by a patient with
diagnosis. Moreover, between 70% and 90% of AKP is retropatellar or peripatellar pain. The loca-
individuals with AKP have recurrent or chronic tion of the pain is crucial for making a diagnosis.
pain.5 Chronic pain is a multidimensional experi- However, it is often difficult for a patient to isolate
ence that requires consideration of sensory features the focus of pain. In response to a query about the
as well as affective and cognitive features.6 That is pain’s location, he or she may simply put a hand
to say, chronic pain affects a patient psychologically. over the anterior aspect of the knee. The pain may
To cite: Sanchis-Alfonso V, AKP provokes both psychological limitations and even be popliteal. Pain diagrams, on which patients
McConnell J, Monllau JC, disability, which may arise more from the psycho- indicate the site of pain on drawings of the knee,
et al. JISAKOS 2016;1: logical affectation than from the pain itself.7 The could be helpful. It is also important to determine
161–173. WHO defines disability as ‘a limitation of function whether the pain appears, or is aggravated by
Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033 Copyright © 2016 ISAKOS 161
 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

activities that load the patellofemoral joint (PFJ), such as climb- activity is of importance in the origin of AKP. The identification
ing and descending the stairs, squatting, using a car clutch (if the and careful management of the activities associated with the
left knee is in pain), wearing high-heeled shoes, and sitting with onset and endurance of AKP are key elements for successful
prolonged knee flexion (-movie sign-), and whether extending treatment.18 Symptoms in both knees are common and may
the knee improves the pain. move from one knee to the other over time.
Aside from pain, other symptoms are a giving-way sensation AKP is often described as dull with intermittent episodes of
—walking straight on, especially when using the stairs or ramps, sharp acute pain. In obtaining the history, it is important to
and crepitus. The giving-way episodes are due to a sudden quantify the pain. Pain is sometimes disproportionate due to
reflex inhibition and/or atrophy of the quadriceps. It is import- existing hyperalgesia (heightened reaction to stimuli, ie, nor-
ant to establish if patellar instability is associated with the pain mally painful) or allodynia ( pain due to stimuli that do not
since both the treatment and the prognosis are very different in usually bring on pain).22 These patients belong to the AKP
the patient with AKP secondary to patellar instability compared subset of neuropathic pain. Finally, in cases preceded by realign-
with the patient with AKP without patellar instability. Crepitus ment surgery in which pain and disability are much worse than
is common, although it is insignificant in most cases. For the preoperative symptoms that prompted surgery, there should
example, Abernethy et al21 found asymptomatic crepitus in be suspicion of an iatrogenic medial patellar instability (IMPI).23
62% of first-year medical students. In addition to pain, which is the fundamental symptom, these
AKP onset is generally insidious and without trauma, which patients experience disability to a greater or lesser degree.
reflects an overuse condition or an underlying malalignment. Therefore, it is also important to quantify the disability.
Overuse can be brought on by a new activity or an increase in Patients with AKP very often experience anxiety, depression,
frequency or intensity of a customary activity. History should be kinesiophobia (the fear that a manoeuvre will cause more injury
geared towards determining which supraphysiological loading or a reinjury and pain) and catastrophising (the belief that pain
will worsen and cannot be relieved).7 These psychological
factors play an important role as pain modulators. Even if the
structural findings are clear, psychological factors influence and
Box 1 Key articles (historic evolution), according to the modify pain sensation as well as subsequent impairment and can
authors, on anterior knee pain (AKP) serve as barriers to recovery.20 Therefore, it is essential to recog-
nise and quantify the existence of these psychological issues to
have a holistic view of a particular patient and plan the best
▸ Merchant et al11 in 1974 described in depth the
treatment (box 2).
roentgenographic analysis of patellofemoral congruence.
▸ Fulkerson12 described in 1983 the anteromedialisation of the
tibial tuberosity. Physical examination
▸ In 1985, Fulkerson et al13 was the first to describe nerve The first objective of physical examination is to pinpoint the
damage in the lateral retinaculum of patients with intractable painful area, and to replicate the symptoms. The location of the
patellofemoral pain requiring lateral retinacular release or
realignment of the patellofemoral joint. He stated that it is
likely that the lateral retinaculum itself is painful in many
Box 2 Outcome measures
patients with patellofemoral malalignment.
▸ Hughston and Deese14 described, for the first time in 1988,
medial patellar instability as a complication of lateral ▸ Using tools such as the Visual Analogue Scale (VAS) of pain
retinacular release that provokes incapacitating AKP. is important in order to quantify the pain at baseline and to
▸ McConnell15 was the first, in 1996, to propose the use of demonstrate and monitor improvement with the treatment.
tape to exert a force on the patella to improve alignment and The 10 cm VAS is a valid and responsive outcome measure
tracking, this way AKP is diminished. for anterior knee pain, with a minimum clinically important
▸ Sanchis-Alfonso et al,16 in 1998, performed a quantitative difference of 2 cm.24
analysis of nerve changes in the lateral retinaculum in ▸ If the presence of neuropathic pain is suspected, validated
patients with AKP. self-administered scales that are specific for neuropathic
▸ Powers,17 in 2003, introduced one of the most important pain, such as the Leeds Assessment of Neuropathic
concepts of the past 13 years in AKP aetiology: the proximal Symptoms and Signs (LANSS) Pain Scale, should be used.25
control. This new philosophy links abnormal femur rotation ▸ Algometry may help clinicians in recognising patients with
with AKP. The rotation of the femur underneath the patella in complex regional pain syndrome (CRPS). If surgeons are
the transverse plane leads to abnormal patellar tracking and aware of the extent of the CRPS preoperatively, they would
therefore patellofemoral imbalance and finally pain. This means be very cautious to not operate as the symptoms will only
that the primary problem is not in the patella but in the femur. worsen.
▸ Dye18 popularised in 2005 the tissue homeostasis perspective ▸ The disability may be quantified by using specific validated
to evaluate and treat patients with AKP. According to Dye, functional self-administered scales such as the Kujala test26
the loss of both osseous and soft tissue homeostasis is more and the Tegner activity scale.27 It is also necessary to know
important in the genesis of AKP than structural a patient’s activity level prior to the treatment and his/her
characteristics. objectives in order to review realistic goals of the treatment.
▸ Näslund et al,19 in 2007, demonstrated the importance of ▸ We should routinely incorporate validated self-administered
ischaemia in the genesis of pain in a subset of patients with AKP screening tests for anxiety and depression—Hospital Anxiety
▸ Domenech and Sanchis-Alfonso7 20 performed in 2013 and and Depression Scale (HADS),28 catastrophising—Pain
2014 the most detailed analysis of psychological factors Catastrophizing Scale (PCS),29 and kinesiophobia—Tampa
acting as pain modulators in AKP. Scale for Kinesiophobia (TSK)30 in a patient’s history.

162 Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033

 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

pain is crucial because it is able to indicate the injured structure, AKP is frequently associated with a reduced flexibility of these
which is really helpful in diagnosing and planning treatment. structures.31
Tenderness over the lateral retinaculum is a frequent finding. Baker et al35 showed abnormal knee joint proprioception in
Therefore, we must evaluate lateral retinaculum tightness using those with AKP. Although they could not determine if the
the patellar glide test.31 In order to exclude the possibility that abnormality preceded AKP or was secondary to it, their results
AKP originates in the patellofemoral articular surfaces, the support the inclusion of specific proprioceptive training in treat-
axial patellar compression test is used.31 Moreover, the ment. The active or passive joint position reproduction can be
sustained knee flexion test allows one to rule out pain used to evaluate proprioception.
brought on by an increase in intraosseous patellar pressure.32 Normally, when a patient with AKP is seen in a clinic, the
Palpation of the inferior pole of the patella must be focus is on the knee and only that structure is studied. This
performed in all cases because pain is very frequently located in focus is a mistake, because other important aetiological factors
that area.31 Moreover, Hoffa’s fat pad should not be overlooked distant from the knee can be responsible for the pain.36 Strong
as a cause of pain; it should always be examined while perform- evidence currently exists that patients with AKP have deficits in
ing Hoffa’s test because it can be a source of disabling pain hip abduction, hip extension and external rotation strength.37
(figure 1).33 Existing scars should be palpated and Tinel’s sign Therefore, it is mandatory in the clinical examination to evalu-
carried out to detect neuromas. Improvement in the patient’s ate hip abduction strength, hip extension strength and hip exter-
pain after selective injection with local anaesthetics or with nal rotation isometric strength, which can be done with a
unloading functional taping leads us to think that specific knee manual dynamometer. Moreover, a patient with AKP may have
soft tissue may be the origin of pain. When a neuropathic origin core muscle weakness, so it is also important to evaluate the
of pain is suspected, pressure algometry, which provides a meas- core muscle endurance.38 Both core and hip weaknesses lead to
urement of pressure pain threshold by applying progressive pres- dynamic malalignment of the lower extremity that influences
sure to a given body point using an algometer, is helpful. patellar tracking. Tibial and femoral rotation should also be
Female adolescents with AKP have been demonstrated to have a evaluated because of their influence on the patellofemoral
lower pressure pain threshold in comparison with a control contact area and pressure39 (figures 3 and 4). Although lower
group.22 extremity rotational deformities might increase the risk of AKP,
Most patients with AKP will develop a quadriceps avoidance these deformities alone are not enough to provoke AKP; they
gait pattern to decrease the PFJ reaction force and thereby the are only predisposing factors.40 AKP is correlated with lateral-
pain.31 Notably, a knee extension strength deficit appears to be isation of the tibial tubercle (figure 5).41 When the knee is
a predictor of AKP.34 Hence, it is mandatory to evaluate quadri- flexed 90°, the tubercle sulcus angle should be 0°.42
ceps atrophy and isometric strength of the quadriceps, which Currently, evaluation of the PFJ tends to be done under con-
can be done with a manual dynamometer. ditions that simulate realistic functional demands using specific
Moreover, it is necessary to evaluate the flexibility in the functional tasks rather than specific tests of the patella.43 Our
quadriceps, hamstring, gastrocnemius muscles, the iliotibial preferred activity to evaluate patients with AKP is descending
band (ITB) and anterior hip structures (figure 2), given that the stairs because it is the most demanding of all the activities of

Figure 1 In patients with impingement of the Hoffa fat pad, pain is dramatically exacerbated by quadriceps contraction (B) or passive knee
extension (C), while applying pressure of the fat pad with the fingers (A,B,C), because this movement causes a small posterior tilt of the inferior
pole of the patella, which impinges on an inflamed and sensitised infrapatellar fat pad.
Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033 163
 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

Feet examination is crucial because pronated feet have an

important role in the genesis of AKP.31 Lastly, functional hallux
limitus cannot be forgotten as a potential predisposing factor
for AKP.44 It can be demonstrated by a loss of dorsal flexion of
the first metatarsophalangeal joint with the ankle in dorsal
flexion.44
Finally, if an IMPI is suspected, the Fulkerson relocation test
is useful.45 To perform this test, the patella is held medially in
extension and then released on abrupt knee flexion. It is a pro-
vocative test, and therefore reproduction of symptomatology
with this manoeuvre strongly suggests medial patellar instability.
Figure 2 Assessment of the flexibility of the anterior hip structures. Imaging
AKP is basically a clinical diagnosis, with imaging only assisting
daily living (ADL) with regard to the knees since it requires sub- to complete the diagnosis. Imaging studies are aimed at quanti-
stantial control in the quadriceps contraction eccentric phase. fying the pathology and checking for other pathologies that
Therefore, we perform the step-down task.17 The patient steps could simulate femoropatellar pathology.
down slowly from a step. In this task, the limb going down only The standing anteroposterior view, a true lateral view, and
brushes the floor with the heel and then goes back to full knee axial X-rays should be obtained for all patients with AKP.
extension. Moreover, we perform the one-legged squat task These X-rays are the first steps for imaging. In cases refractory
(figure 6) and the landing from a drop task.17 During these to conservative treatment, CT and MRI should be considered.
tasks, many patients with AKP have an excessive functional knee CT shows the bone morphology and allows the measurement of
valgus.17 important knee parameters, such as the tibial tubercle-trochlear

Figure 3 Both internal femoral rotation and external tibial rotation increase pressure on the lateral side of the patellofemoral joint.39 Squinting
patella when the patient is standing with their feet forward. It is due mainly to femoral anteversion, but it can be seen in cases with external tibial
torsion without femoral anteversion as occurs in this particular case. Examination of the hips demonstrates equal internal and external rotation. In
patients with an increment of the femoral anteversion, the internal rotation of the hip is greater than the external rotation. We must note that
increased foot pronation can also lead to increased internal tibial rotation and thus ‘squinting patellae’.

164 Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033

 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

Figure 4 Measurement of external tibial rotation using a goniometer and by means of CT. The patient is positioned prone with the knee flexed to
90° and the ankle in a neutral position of flexion–extension. (A) Transcondylar axis, (C) longitudinal axis of the femur, and (B) transmalleolar axis.
The amount of tibial rotation equals the angle AB.

groove distance (TT-TG), that allow for evaluation of maltrack- findings such as lateral patellar displacement may be frequently
ing. Moreover, CT scans can detect and quantify torsional seen in asymptomatic patients.31 Patellofemoral chondropathy is
anomalies of the lower limbs (figure 4). MRI is useful for detec- also extremely common, and only a small number of patients
tion of cartilage lesions in the PFJ, intraosseous oedema, syn- with a patellar chondral lesion have AKP related to it.
ovial plica and soft tissue impingement (figure 7). Imaging Therefore, a surgical option ought never to be based only on
imaging techniques, as the correlation between clinical findings
and imaging is not good. Three-dimensional CT could be clinic-
ally useful in planning revision surgery in patients with AKP
after medial patellofemoral ligament reconstruction to detect
femoral tunnel malposition (figure 8).46
In selected cases, such as revision surgery or workers’ com-
pensation patients, technetium-99m-methylene diphosphonate
scintigraphy may be helpful. It shows the metabolic and geo-
graphic characteristics of bone homeostasis.18 A relationship has
been demonstrated between an abnormally increased technetium
bone scan of the PFJ and AKP.18 Additionally, an association
between restoration to normality of the bone scan and the reso-
lution of AKP after conservative treatment has also been docu-
mented.18 Näslund et al47 found that nearly 50% of patients
with AKP show a diffuse uptake in the scintigraphy in one or
more of the bony compartments of the knee joint.
Finally, in those cases in which an IMPI is suspected, stress
radiography48 or stress axial CT scans49 will be helpful. They
allow one to objectively document and quantify medial patellar
instability. The difference between the displacement of both
sides carries more importance than the absolute amount of dis-
placement (figure 9).

NON-OPERATIVE TREATMENT
Since AKP is a multifactorial problem, non-operative manage-
ment depends on the examination findings. The clinician needs
to decrease the strain of excessively loaded and painful soft
Figure 5 Lateralisation of the tibial tubercle correlates with anterior tissues around the PFJ, improving the seating of the patella in
knee pain. When the knee flexes 90°, the patella usually is captured the trochlea, as well as to optimise the lower limb mechanics,
within the trochlea. In an asymptomatic healthy person, the tibial which should decrease the patient’s symptoms and, if main-
tubercle femoral sulcus angle should be 0° at 90° of knee flexion. This tained, will minimise any recurrences of symptoms. A multi-
angle’s measurement indicates the lateral displacement of the tubercle modal physiotherapy programme is effective in reducing AKP
with reference to the femoral sulcus. symptoms.50 51
Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033 165
 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

space narrowing.54 Wang et al55 found that optimising the

vastus medialis (VM) size was critical to reducing osteoarthritic
progression and decreasing the need for a total knee replace-
ment. Recent evidence of the long-term outcome of treatment
for adolescents with AKP, who are supposedly compliant with a
multimodal exercise programme, is fairly poor, although the
same authors found that the majority of adolescents did not
perform the home exercises correctly 2 weeks after their initial
instruction.56 It is hypothesised that the adolescents whose
symptoms fail to improve will develop PFOA.57 Therefore, it is
imperative for clinicians to ensure from the beginning that they
get ‘buy in’ with the treatment to ensure compliance, so the
clinician must educate the patient about why they have symp-
toms, explaining where the pain is coming from, what has con-
tributed to the pain and in the first visit significantly reduce the
symptoms.

Explanation to the patient

A useful tool for clinicians to give a patient is a modified version
of Dye’s homeostasis of the knee graph, so the patient under-
stands the issues of load intensity and load frequency contribut-
ing to AKP symptoms (figure 10). The clinician needs to inform
the patient about the effect of ADL on knee joint loading, so
the patient understands about keeping inside their envelope of
function to ensure that they are not aggravating their symptoms
further (box 3).
After the patient has been educated about the effect of load
through the knee, the clinician needs to show the patient in
front of a mirror his/her lower limb alignment, so the impact of
the internally rotated femurs and/or pronated feet can be readily
seen. A valuable and easy demonstration to reinforce how prox-
imal and distal factors affect the knee is for the clinician to ask
the patient to squeeze their gluteals together, causing external
rotation of the femurs and hence a straightening of the knees.
Figure 6 Functional or dynamic knee valgus visualised by a The final piece of vital information to improve treatment com-
one-legged squat. It may lead to lateral patellar maltracking. We can pliance is for the patient to palpate their size of the fat pad on
see an internal rotation of the femur secondary to weakness of hip the symptomatic and asymptomatic sides (the fat pad will be
abductors and external rotator muscles. The fact that the patient larger in size on the symptomatic side), as well as to feel the dir-
cannot keep up the hip indicates the weakness of hip abductors. We
ection their patella moves with a quadriceps contraction (the
can observe an internal rotation of the tibia secondary to pes pronatus.
patella will usually move laterally out of the line of the femur).
Appropriate education and understanding helps allay the fear of
Knee pain inhibits quadriceps contraction, decreasing the pain, which lessens the likelihood of the condition progressing
loading ability of the knee, whereas fear of pain only decreases to complex regional pain syndrome (CRPS).
vastus medialis oblique (VMO) activity.52 In middle-aged indivi-
duals with decreased quadriceps strength, there are reports of Recognition and treatment of CRPS
increased knee pain,53 but MRI scans have also demonstrated Patients with AKP, manifesting as CRPS, will demonstrate a tem-
increased patellofemoral cartilage loss and tibiofemoral joint perature difference around the knee, with the knee being colder

Figure 7 Axial MRI. Impingement of

a peripatellar synovitis (arrow).

166 Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033

 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

Figure 8 (A) Three-dimensional CT. Observe a very anterior femoral tunnel used for medial patellofemoral ligament reconstruction (arrow) and (B)
a severe patellar chondropathy secondary to this surgical mistake.

than the surrounding tissues, particularly the medial aspect. of tape by lifting the fat pad tissue from the tibial tuberosity
There may also be a mottling of the skin. It is imperative that towards the patella and anchoring behind the medial and lateral
patients see and feel this so they can understand the effects of epicondyles, respectively (figure 12). The patient needs to keep
the sympathetic nervous system. An explanation of the effects of the tape on all the time until the symptoms have subsided,
centrally maintained pain and a regime of desensitising is which means they need to be shown how to tape their own
helpful in breaking the pain cycle (figure 11). While there is a knee, by sitting with the leg out straight on the edge of a chair,
significant temperature difference around the knee, the clinician so the hamstrings and quadriceps are relaxed and the patella can
should not touch the patient’s knee or direct specific treatment be easily moved (figure 13).
to the knee as it will make the symptoms worse. Additional control of the patellofemoral alignment may be
obtained by rotating the femur externally with tape beginning
Unloading painful tissues around the knee on the femur and anchoring on the sacrum.
This involves improving the position of the patella on the femur
with tape and decreasing the stress through any abnormally
loaded structure, which in many cases will be the infrapatellar Muscle training
fat pad (IFP).58 59 Before applying tape, the clinician needs to In the past, AKP rehabilitation has centred around
assess which or all of the following patellar malalignment com- non-weight-bearing quadriceps activities (straight leg raises and
ponents are present to determine how best to improve the short arc quadriceps—lifting the lower leg over a rolled towel),
seating of the patella in the trochlea for each individual patient: which have been shown to be not as effective as glutaeal based
(1) posterior tilt of the inferior pole of the patella into the IFP, training in the short term, promoting rectus femoris rather than
which is the most critical component to recognise as taping too vasti activity and in some situations shown to aggravate the
low on the patella can inflame the IFP; (2) lateral tilt of the patient’s symptoms, particularly if the IFP is inflamed.60 For
patella, indicating tight deep lateral retinacular tissues, which muscle training to have a lasting effect, it should involve chan-
may also need to be stretched manually as well as with tape; (3) ging the way a patient moves, so PFJ loading can change. The
lateral glide, indicating tight superficial retinacular structures as exercise programme should therefore consist of neuromuscular,
well as late onset of VMO contraction and (4) rotation of the weight-bearing training for the whole lower limb, as the femoral
inferior pole of the patella such that the long axis of the patella and foot positions contribute to altering patellofemoral loading
does not align with the long axis of the femur. and weight-bearing promotes balanced quadriceps activation.61
A symptom producing weight-bearing activity should be used Jensen et al62 showed that 4 weeks of visuomotor skill training,
to determine the effectiveness of the taping, with symptom not strength training, improved corticospinal excitability,
reduction needing to be at least 50%. In some cases, the fat pad reinforcing the importance of training specificity, particularly
may need to be further unloaded with tape by using two pieces with regard to gravitational position and force precision.

Figure 9 Axial stress radiograph of

the left knee enables us to detect an
iatrogenic medial patellar instability.

Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033 167

 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

Figure 10 Dye’s homeostasis of the knee. To maintain the envelope

of function and remain symptom free the patient must keep the
intensity and frequency of the load below the threshold.

Since AKP symptoms are generally increased with loaded

knee flexion, clinicians need to retrain the limb position initially
for walking. To simulate walking, the patient stands next to the
wall with their body turned 45o into the wall, with all their
weight through the leg furthest from the wall and the knee of
the leg closest to the wall bent onto the wall for balance. The
patient is instructed to stand tall with the weight back through Figure 11 Desensitising the knee—a variety of different textured
the heel, posteriorly tilt the pelvis and unlock the knee of the objects need to be rubbed around the knee by the patient. The objects
standing leg, while externally rotating the thigh slightly, holding could include tissue, cotton wool, sandpaper, ice, etc. This needs to be
done for 5 min every day—30 s to 1 min with each object for about a
the position for 30 s (figure 14A). Degrees of complexity can be
month.
added by using a resistance band tied around the ankle of the
non-weight-bearing leg so the patient can pull the band forward
and back, increasing the resistance for the walking simulation, treadmill, the patient can change their position accordingly,
as well as changing the surface stability using a bosu ball or, if based on evaluating their limb position as seen in the mirror.
the patient wants to practise at home, standing on a pillow Simple cues are also effective in changing loading such as
(figure 14B). landing with soft knees or landing further towards the toes as
Daily activity training exercises need to be easily incorporated this has been shown to decrease PFJ stress.63 Decreased tibiofe-
into a patient’s life, so while waiting for the elevator or a bus, moral dorsiflexion and subtalar mobility increases the dynamic
the patient can squeeze their glutaeals and slightly bend and valgus collapse seen in many individuals with AKP, so the
then straighten, not locking, both knees (the first 30o), keeping
their knees over the middle of their feet. Patients can also prac-
tise the walk stance position and flex and extend their knees
slightly, keeping the knees over the second and third toes. Other
daily strategies involve teaching a patient how to sit and stand
without using their hands to get up and keeping their hips,
knees and feet in alignment (avoiding valgus collapse). Since
many individuals are unaware of their posture when they move,
mirrors can be incorporated as useful feedback tools early in the
rehabilitation programme so that when new activities are added,
such as stepping on and off steps and running retraining on a

Box 3 The patellofemoral joint (PFJ) reaction force and

activities of daily living

▸ 0.5× body weight through PFJ with level walking.

▸ 1.5× body weight through PFJ with cycling on a stationary
bike. Figure 12 Unloading the fat pad—the tape needs to start on the
▸ 3–4× body weight through PFJ with ascending and superior half of the patella to tilt the inferior pole of the patella out of
descending stairs. the fat pad, then the fat pad needs to be unloaded by starting at the
▸ 7–8× body weight through PFJ with squatting. tibial tubercle with each piece of tape and taping towards the medial
▸ 20× body weight through PFJ with jumping. and lateral joint lines, forming a wide v shape. The soft tissue is lifted
towards the patella to decrease the tension on the tissues.

168 Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033

 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

Figure 13 Self-tape—the patient sits on the edge of a chair with the

leg relaxed and extended so it is easy to move the patella. This is a
particularly good way to achieve patella correction as it eliminates the Figure 15 Mobilisation of the subtalar joint—this is performed in
problem of tight hamstrings causing knee flexion which can be a side-lying with the foot maintained at neutral dorsiflexion to simulate
problem when the patient tapes the knee in long sitting. heel strike. The clinician everts the calcaneum to increase subtalar
pronation immediately after heel strike.

clinician can mobilise to increase the range of the joint/s respon-

minimising patellofemoral symptoms.65 Although some authors
sible (figure 15).64
have found that some patients with AKP are that running bare-
The clinician needs to give advice about footwear and ortho-
foot is better for patients with AKP as it decreases PFJ stress, so
tics. If the navicular drop test is positive (ie, if there is a large
they recommend minimalist running shoes with no orthotics, so
difference between the non-weight-bearing and weight-bearing
there is scope for further investigation identifying different foot
arch height), then off the shelf foot orthotics are helpful in
postures, categorising responders and non-responders to foot or
no foot intervention.
Since muscle tightness can contribute to AKP symptoms,
appropriate stretches should be included in the treatment
regimen. The involved muscles may include anterior hip struc-
tures, hamstrings, gastrocnemius, rectus femoris as well as
tensor fasciae latae (TFL)/ITB (figure 16).

Body management strategies

Lankhorst et al66 recently found that patients with AKP who
have a delay in initiating treatment and a lower AKP scale at

Figure 14 (A) Glutaeal training—the patient stands 45° towards the

wall, lifts the knee of the leg closest to the wall onto the wall for
balance. All the patient’s weight is on the standing leg, the weight is Figure 16 Hamstrings stretch—the patient sits on a kitchen bench or
back through the heel, the standing knee is slightly flexed, the pelvis is somewhere so the legs do not touch the ground. The patient sits tall—
slightly posteriorly tilted. The patient stands tall and very slightly maintaining a neutral spine, and trunk at 90° to the hips, then the
rotates the standing leg thigh, so the patient feels the glutaeals patient straightens the leg without losing control of the trunk position.
burning. This exercise is performed frequently throughout the day. This This position is held for 15 s and repeated. The leg should not fully
is brain training—changing the synergistic activation pattern of the extend, as this will irritate the fat pad—if the clinician is worried about
lower extremity muscles for walking and running. (B) This exercise can the fat pad being inflamed, then the patient can lean further forward
be progressed by having the patient stand on a pillow to simulate while maintaining a neutral spine which will decrease the load through
rough ground. the patellofemoral joint.
Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033 169
 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

diagnosis are more likely to still have knee pain 6–8 years later,
concluding that clinicians need to send patients for appropriate
treatment early. For improved long-term outcome for patients
with AKP, there should be a paradigm shift in the way clinicians
manage AKP. Since the word exercise conjures up an onerous,
time-consuming message to many patients, clinicians need to
empower individuals to take charge of their symptoms, empha-
sising the need to reinforce appropriate limb alignment with
daily practice, requiring a small amount of time, just like they
would keep their teeth in good health by regular brushing. To
ensure the success of the daily strategies and to keep symptoms
under control, the patient would need to visit the clinician every
6 months or 12 months for a ‘body maintenance check’, similar
to a car service, but for the body, as chronic musculoskeletal
conditions are not cured but are managed, so this is one way
that could ensure long-term compliance with a self-management
programme.

SURGICAL TREATMENT
The primary treatment for all patients with AKP is non-
operative. When non-operative measures fail, and when a
Figure 17 Peripatellar synovitis (arrow).
patient is in a dysfunctional state requiring intervention, the
goal must be to identify the specific mechanical and/or physical
origin of the pain before considering any surgery. One should with small nerve injury13 16 and/or substance P production.69
also understand if catastrophising and kinesiophobia are signifi- Eradication or transection of the painful small nerves causing
cant factors before contemplating surgery because psychological this pain through a localised excision or release is usually suc-
factors are pain modulators.20 However, their presence does not cessful.68 One must be particularly careful, however, not to
contraindicate surgery if there are objective abnormalities and if create a patella imbalance by release of a painful retinacular
exhaust non-operative measures have failed. The first goal is to structure that might be also giving important support within the
identify whether the pain is articular or extra-articular. The fol- extensor mechanism. This will be particularly true in patients
lowing entities may be treated successfully with surgery. with trochlear dysplasia and imbalance around the patella. In
such patients, appropriate treatment of the imbalance and/or
Plica/localised synovial hypertrophy compensatory surgery for the dysplasia may be necessary at the
A pathological, painful plica is most readily identified by palpat- time of retinacular resection or release. Electrosurgical arthro-
ing it in the region in which the patient notes pain, usually in scopic patellar denervation could be a good solution for selected
the medial infrapatellar space. Painful plica may be found in patients with recalcitrant patellofemoral pain without evident
other parts of the knee joint too, so careful palpation around mechanical anomalies.70
the joint will identify if there is snapping or evidence of a
tender intra-articular band of tissue which might be causing
pain. In such cases, the best treatment is arthroscopic resection Articular pain
of the painful intra-articular impinging synovial plica structure. Articular causes of AKP have been poorly understood. The con-
Localised synovial hypertrophy around the inferior pole of the nection between articular lesions of the patella or trochlea and
patella and impingement of a peripatellar synovitis (figure 17) AKP is variable. Many patients with patellofemoral articular
could also be successfully treated by means of electrosurgical lesions have no pain, whereas some people, with cartilage soft-
synovectomy.18 67 ening only, have excruciating, disabling pain. Therefore, it
behoves the surgeon who is contemplating intervention to
Retinacular pain assure whether or not a patellofemoral articular lesion is a
As identified by Kasim and Fulkerson,68 any peripatellar retina- source of pain. Clinical examination and imaging are essential,
cular structure could be a source of AKP. Such pain often goes along with a detailed history regarding pain triggers. Between
undiagnosed and is most readily identified by careful palpation the history, observation of the patient doing a single-leg knee
of every component around the patella, above and below as well bend, and imaging studies to find potential areas of focal over-
as medial and lateral to the patella itself, looking for a source of load, painful lesion localisation should be possible in the major-
tenderness which reproduces the patient’s pain. Such causes of ity of cases. Fluid signal change on T2-weighted MRIs are
pain may be treated effectively by injection of a corticosteroid diagnostic, as is a positive radionuclide scan. Ho et al71 have
and/or stretching, but when chronic, retinacular pain is disab- shown fluid signal changes in subchondral bone correlated with
ling, local excision or release may be beneficial and curative. overload. If the imaging studies match the degree of knee
Therefore, identification and surgical extirpation of a chronic flexion in which pain occurs, one has most likely found an
source of retinacular pain are important. Such retinacular pain articular pain source.
sources may be related to chronic stress as in a chronically tilted Unfortunately, imaging studies do not necessarily identify a
patella causing pain in the lateral retinaculum. The vastus latera- lesion in all cases. The presence of an objective tilt on axial radi-
lis tendon may become constantly irritated in some patients. ography strongly supports focal overload of the lateral PFJ, but
Pain in the VM tendon, the patellar tendon or the quadriceps a lack of tilt does not rule out focal overload of the distal or
tendon are treatable by surgical eradication of the chronically lateral patella that may occur functionally in some patients, most
irritated tissue. Such retinacular pain is sometimes associated often female, with delayed centring of the patella in the femoral
170 Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033
 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

Box 4 Key issues in patient selection for surgical Box 5 Tips and tricks in the surgical treatment of
procedures in the treatment of patellofemoral pain patellofemoral pain

▸ Exhaust all non-operative treatment methods first. ▸ Use exhaustive physical examination and imaging, and
▸ Be aware of catastrophising and kinesiophobia and be sometimes diagnostic arthroscopy, to accurately define the
particularly sure of objective findings in patients prone to site of pain origin.
this condition. ▸ Use minimalistic approaches whenever possible and
▸ In patients who have already had a patellofemoral surgery, appropriate.
be particularly suspicious of complex instability problems ▸ Use arthroscopy as a diagnostic tool as well as for treatment.
such as medial subluxation and neuroma. Treatment options may vary depending on specific
▸ Most patients have real pain and one should not assume arthroscopic findings. Don’t perform lateral release for medial
that non-operative measures will work in all patients. softening. Lateral release is indicated only for lateral
▸ Make sure that the patient understands the nature of any softening with patella tilt and a tight lateral retinaculum.
proposed surgery and also be sure that the patient cannot ▸ Drilling of articular lesions on the patella should generally
live with the pain. Modification of activity may be an be accompanied by rest and motion with limited
acceptable alternative to some, particularly older patients. weight-bearing and loading of the joint for about 6 weeks in
▸ Design the surgical approach very specifically to target sites most patients.
of pain generation. ▸ Unloading of a painful articular lesion on the distal and/or
▸ Be sure to have permission for any potential procedure that lateral patella by anteromedial tibial tubercle transfer, when
might be needed at the time of surgery. the patella is overloaded laterally, is a powerful surgical
▸ Complex regional pain problems should be treated before option in the treatment of patellofemoral pain resulting from
surgical intervention, and surgical intervention should be lateral patella cartilage softening or breakdown.
carefully coordinated with any pain management that is ▸ Lateral retinacular release or lengthening will often give
ongoing. relief of pain in patients with isolated patella tilt with
minimal cartilage breakdown and a tight retinaculum.
▸ Release only what is needed and never release without a
good objective reason to do so.
▸ Always encourage early motion without weight-bearing only
trochlea in early knee flexion. Such patients may have dysfunc-
after tibial tuberosity osteotomy or drilling—one bend a day
tion originating at the hip or knee level, or structural trochlea
is all that is needed.
dysplasia may lead to focal overload of the distal and/or distal/
▸ Maintain quadriceps tone after surgery.
lateral patella that is held on the lateral trochlea too long in
early knee flexion. Pain in such patients typically occurs on step-
ping down with the contralateral leg. Thus, the distal patella of
the affected side is brought into the focal overload orientation in some patients, presumably by creating a subchondral ‘healing
on entry into the trochlea with initial knee flexion. Such pro- response’ and opportunity for restoration of subchondral
blems may be ameliorated by core strengthening, VMO homeostasis.18 In this particular case, we recommend immobil-
strengthening and non-operative work including mobilisation isation because we are looking for subchondral reconstitution,
that benefits patellofemoral tracking, but such treatment often not cartilage restitution. Bone marrow stimulation by drilling
fails once articular cartilage has begun to deteriorate causing adds the possibility of deep cartilage restoration and subchon-
chronic focal subchondral bone irritation. This is first mani- dral remodelling. In patients with AKP and patellar hyperten-
fested as softening or blistering of the overloaded distal/lateral sion, extra-articular patellar decompression may offer good
or lateral patella articular cartilage from recurrent focal overload results.72
related to structural malalignment and/or functional imbalance AMZ provides more profound unloading of the distal and
(s) of the extensor mechanism. lateral patella when focal overload related to patella malalign-
Some patients may experience painful clicking related to a ment cannot be relieved sufficiently by lateral lengthening or
loose articular fragment in which case an arthroscopic chondro- release. Once the lateral articular cartilage has collapsed, lateral
plasty may provide considerable relief. Microfracture or abrasion release is less effective and definitive unloading by AMZ may be
arthroplasty has typically been less effective on the patella. necessary.73 Pain relief and return to sports are expected after
Lateral facetectomy has been helpful in some patients with AMZ for appropriate patients.74 In selected cases, torsional cor-
specific impingement on the lateral overhanging facet. rection surgery should be considered.75
Unloading of a painful lateral patella articular lesion by antero- In more extreme cases in which patellofemoral articular pain
medialization (AMZ) of the tibial tuberosity,12 however, pro- is related to focal or diffuse patellofemoral injury which cannot
vides more profound and prolonged benefit than lateral be relieved by unloading, articular resurfacing may be war-
facetectomy. ranted. A painful medial or trochlear articular lesion may be
Treatment is best directed at relief of pressure on the area of excised and resurfaced by an autogenous osteoarticular trans-
patella focal overload. In patients with an objective patella tilt plant, allograft or biological resurfacing procedure, but results
and a tight lateral retinaculum, lateral release or lengthening with these approaches have been mixed. Osteoarticular allograft
may be highly effective to unload the lateral, overloaded patella resurfacing may be appropriate and can be highly effective in
facet. When the distal patella is more severely involved and relieving pain, but carry the risk of late failure.76 Similarly,
changes extend towards the distal, medial or central aspect of patellofemoral arthroplasty may become necessary, particularly
the patella, lateral release alone may not be sufficient. in older patients and patients with more diffuse patellofemoral
Subchondral drilling followed by 6 weeks’ immobilisation works destruction. In general, most patients with patellofemoral
Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033 171
 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

3 Boling M, Padua D, Marshall S, et al. Gender differences in the incidence and
prevalence of patellofemoral pain syndrome. Scand J Med Sci Sports
Box 6 Pitfalls of patellofemoral surgery for pain 2010;20:723–30.
4 Collins NJ, Bierma-Zeinstra SM, Crossley KM, et al. Prognostic factors for
patellofemoral pain: a multicentre observational analysis. Br J Sports Med
▸ Lateral release of a patella that does not have tilt and a
2013;47:227–33.
tight lateral retinaculum may cause medial instability or 5 Powers CM, Bolgla LA, Callaghan MJ, et al. Patellofemoral pain: proximal, distal,
subluxation thereby making the patient worse. and local factors, 2nd International Research Retreat. J Orthop Sports Phys Ther
▸ Ignoring or missing a symptomatic patella articular lesion 2012;42:A1–54.
will often yield an unsuccessful surgery, particularly if load is 6 Boccard SG, Fitzgerald JJ, Pereira EA, et al. Targeting the affective component of
chronic pain: a case series of deep brain stimulation of the anterior cingulate cortex.
added to the lesion inadvertently. Neurosurgery 2014;74:628–35.
▸ A tibial tubercle transfer osteotomy that is not flat, tapered 7 Domenech J, Sanchis-Alfonso V, López L, et al. Influence of kinesiophobia and
anteriorly at the distal osteotomy, or poorly stabilised will catastrophizing on pain and disability in anterior knee pain patients. Knee Surg
put the patient at risk. Sports Traumatol Arthrosc 2013;21:1562–8.
8 Tan SS, van Linschoten RL, van Middelkoop M, et al. Cost-utility of exercise therapy
▸ Retinacular causes of pain are often missed and must be
in adolescents and young adults suffering from the patellofemoral pain syndrome.
identified and treated to gain optimal pain relief. Sometimes Scand J Med Sci Sports 2010;20:568–79.
this requires a local excision of neuromatous or chronically 9 Crossley KM. Is patellofemoral osteoarthritis a common sequela of patellofemoral
irritated tissue. pain? Br J Sports Med 2014;48:409–10.
10 Rankin G, Rushton A, Olver P, et al. Chartered Society of Physiotherapy’s
identification of national research priorities for physiotherapy using a modified
Delphi technique. Physiotherapy 2012;98:260–72.
articular sources of pain, however, can be managed with releas- 11 Merchant AC, Mercer RL, Jacobsen RH, et al. Roentgenographic analysis of
ing and unloading alternatives. patellofemoral congruence. J Bone Joint Surg Am 1974;56:1391–6.
12 Fulkerson JP. Anteromedialization of the tibial tuberosity for patellofemoral
malalignment. Clin Orthop Relat Res 1983;(177):176–81.
13 Fulkerson JP, Tennant R, Jaivin JS, et al. Histologic evidence of retinacular nerve
FUTURE DIRECTIONS injury associated with patellofemoral malalignment. Clin Orthop Relat Res
The most challenging patient with AKP in terms of treatment is 1985;197:196–205.
14 Hughston JC, Deese M. Medial subluxation of the patella as a complication of
the neuropathic patient. Current data suggest that repetitive lateral retinacular release. Am J Sports Med 1988;16:383–8.
transcranial magnetic stimulation of the motor cortex, corre- 15 McConnell J. Management of patellofemoral problems. Man Ther
sponding to the patients’ site of pain, could be a complementary 1996;1:60–6.
treatment for patients with chronic neuropathic pain.77 78 This 16 Sanchis-Alfonso V, Roselló-Sastre E, Monteagudo-Castro C, et al. Quantitative
analysis of nerve changes in the lateral retinaculum in patients with isolated
treatment could therefore be considered in the subset of patients symptomatic patellofemoral malalignment. A preliminary study. Am J Sports Med
with neuropathic pain not responding to more conventional 1998;26:703–9.
treatments. Another emerging promising method in the manage- 17 Powers CM. The influence of altered lower-extremity kinematics on patellofemoral
ment of AKP in patients for whom conservative or surgical joint dysfunction: a theoretical perspective. J Orthop Sports Phys Ther
therapy has failed is radiofrequency neurotomy.79 2003;33:639–46.
18 Dye SF. The pathophysiology of patellofemoral pain: a tissue homeostasis
Finally, we are convinced that the so-called biopsychosocial perspective. Clin Orthop Relat Res 2005;436:100–10.
model, currently used in chronic lumbar pain, will soon be 19 Näslund J, Waldén M, Lindberg LG. Decreased pulsatile blood flow in the patella in
applied in patients with AKP to better understand what is hap- patellofemoral pain syndrome. Am J Sports Med 2007;35:1668–73.
pening in them.80 According to this model, anatomic, biological 20 Doménech J, Sanchis-Alfonso V, Espejo B. Changes in catastrophizing and
kinesiophobia are predictive of changes in disability and pain after treatment in
and biomechanical factors must be considered to understand patients with anterior knee pain. Knee Surg Sports Traumatol Arthrosc
pain, as well as psychological and social factors. Among all the 2014;22:2295–300.
psychological factors that have been analysed in the patient with 21 Abernethy PJ, Townsend PR, Rose RM, et al. Is chondromalacia patellae a separate
AKP, the most relevant one from a clinical standpoint is catastro- clinical entity? J Bone Joint Surg Br 1978;60-B:205–10.
phising, which is related to pain as well as to disability.20 22 Rathleff MS, Roos EM, Olesen JL, et al. Lower mechanical pressure pain thresholds
in female adolescents with patellofemoral pain syndrome. J Orthop Sports Phys Ther
Consequently, cognitive behavioural interventions which have 2013;43:414–21.
shown the reduction of catastrophising pain in patients with arth- 23 Sanchis-Alfonso V, Merchant AC. Iatrogenic medial patellar instability: an avoidable
ritis or lumbar pain could also be helpful in patients suffering injury. Arthroscopy 2015;31:1628–32.
from AKP.81 82 In this way, we must note that psychological inter- 24 Crossley KM, Bennell KL, Cowan SM, et al. Analysis of outcome measures for
persons with patellofemoral pain: which are reliable and valid? Arch Phys Med
vention in patients who underwent anterior cruciate ligament Rehabil 2004;85:815–22.
reconstruction has shown significant improvements in the short- 25 Bennett MI, Smith BH, Torrance N, et al. The S-LANSS score for identifying pain of
term clinical results and functional outcomes.83 Catastrophising predominantly neuropathic origin: validation for use in clinical and postal research.
represents a barrier in the recovery from pain and disability, and J Pain 2005;6:149–58.
therefore it should be included in the therapeutic targets to com- 26 Kujala UM, Jaakkola LH, Koskinen SK, et al. Scoring of patellofemoral disorders.
Arthroscopy 1993;9:159–63.
plement and to improve the results of conventional treatments 27 Tegner Y, Lysholm J. Rating systems in the evaluation of knee ligament injuries. Clin
(such as physical therapy and/or surgery) (boxes 4–6). Orthop Relat Res 1985;(198):43–9.
28 Zigmond AS, Snaith RP. The Hospital Anxiety and Depression Scale. Acta Psychiatr
Competing interests None declared. Scand 1983;67:361–70.
Provenance and peer review Commissioned; externally peer reviewed. 29 Sullivan MJL, Bishop SR, Pivik J. The Pain Catastrophizing Scale: development and
validation. Psychol Assess 1995;7:524–32.
30 Kori KS, Miller RP, Todd DD. Kinesiophobia: a new view of chronic pain behavior.
Pain Mang 1990;3:35–43.
REFERENCES 31 Sanchis-Alfonso V, Montesinos-Berry E, Serrano A, et al. Evaluation of the patient
1 Barber Foss KD, Hornsby M, Edwards NM, et al. Is body composition associated with anterior knee pain and patellar instability. In: Sanchis-Alfonso V, ed. Anterior
with an increased risk of developing anterior knee pain in adolescent female Knee pain and patellar instability. London: Springer, 2011:105–22.
athletes? Phys Sportsmed 2012;40:13–19. 32 Hejgaard N, Arnoldi CC. Osteotomy of the patella in the patellofemoral pain
2 Nejati P, Forogh B, Moeineddin R, et al. Patellofemoral pain syndrome in Iranian syndrome. The significance of increased intraosseous pressure during sustained knee
female athletes. Acta Med Iran 2011;49:169–72. flexion. Int Orthop 1984;8:189–94.

172 Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033

 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

State of the Art

33 Dragoo JL, Johnson C, McConnell J. Evaluation and treatment of disorders of the 59 Handfield T, Kramer J. Effect of McConnell taping on perceived pain and knee
infrapatellar fat pad. Sports Med 2012;42:51–67. extensor torques during isokinetic exercise performed by patients with
34 Pappas E, Wong-Tom WM. Prospective predictors of patellofemoral pain syndrome: patellofemoral pain syndrome. Physiotherapy Canada 2000;4:39–44.
a systematic review with meta-analysis. Sports Health 2012;4:115–20. 60 Escamilla RF, Fleisig GS, Zheng N. Biomechanics of the knee during closed kinetic
35 Baker V, Bennell K, Stillman B, et al. Abnormal knee joint position sense in chain and open kinetic chain exercises. Med Sci Sports Exerc 1998;30:556–69.
individuals with patellofemoral pain syndrome. J Orthop Res 2002;20:208–14. 61 Stensdotter AK, Hodges PW, Mellor R, et al. Quadriceps activation in closed and in
36 Sanchis-Alfonso V, Tey M, Monllau JC. A novel association between open kinetic chain exercise. Med Sci Sports Exerc 2003;35:2043–7.
femoroacetabular impingement and anterior knee pain. Pain Res Treat 62 Jensen JL, Marstrand PC, Nielsen JB. Motor skill training and strength training are
2015;2015:937431. associated with different plastic changes in the central nervous system. J Appl
37 Prins MR, van der Wurff P. Females with patellofemoral pain syndrome have weak Physiol 2005;99:1558–68.
hip muscles: a systematic review. Aust J Physiother 2009;55:9–15. 63 Bonacci J, Vicenzino B, Spratford W, et al. Take your shoes off to reduce
38 Earl JE, Hoch AZ. A proximal strengthening program improves pain, function, and patellofemoral joint stress during running. Br J Sports Med 2014;48:425–8.
biomechanics in women with patellofemoral pain syndrome. Am J Sports Med 64 Wyndow N, De Jong A, Rial K, et al. The relationship of foot and ankle mobility to
2011;39:154–63. the frontal plane projection angle in asymptomatic adults. J Foot Ankle Res
39 Lee TQ, Morris G, Csintalan RP. The influence of tibial and femoral rotation on 2016;9:3.
patellofemoral contact area and pressure. J Orthop Sports Phys Ther 65 McPoil TG, Warren M, Vicenzino B, et al. Variations in foot posture and mobility
2003;33:686–93. between individuals with patellofemoral pain and those in a control group. J Am
40 Erkocak OF, Altan E, Altintas M, et al. Lower extremity rotational deformities and Podiatr Med Assoc 2011;101:289–96.
patellofemoral alignment parameters in patients with anterior knee pain. Knee Surg 66 Lankhorst NE, van Middelkoop M, Crossley KM, et al. Factors that predict a poor
Sports Traumatol Arthrosc 2015. Published Online First. outcome 5–8 years after the diagnosis of patellofemoral pain: a multicentre
41 Muneta T, Yamamoto H, Ishibashi T, et al. Computerized tomographic analysis of observational analysis. Br J Sports Med Published Online First: 13 Oct 2015.
tibial tubercle position in the painful female patellofemoral joint. Am J Sports Med doi:10.1136/bjsports-2015-094664.
1994;22:67–71. 67 Maier D, Bornebusch L, Salzmann GM, et al. Mid- and long-term efficacy of the
42 Hughston JC, Walsh WM, Puddu G. Patellar subluxation and dislocation. arthroscopic patellar release for treatment of patellar tendinopathy unresponsive to
Philadelphia: WB Saunders, 1984. nonoperative management. Arthroscopy 2013;29:1338–45.
43 Papadopoulos K, Stasinopoulos D, Ganchev D. A systematic review of reviews in 68 Kasim N, Fulkerson JP. Resection of clinically localized segments of painful
patellofemoral pain syndrome. Exploring the risk factors, diagnostic tests, outcome retinaculum in the treatment of selected patients with anterior knee pain. Am J
measurements and exercise treatment. Open Sports Med J 2015;9:7–17. Sports Med 2000;28:811–14.
44 Vallotton J, Echeverri S. Clinical examination of the patellofemoral patient. In: 69 Sanchis-Alfonso V, Roselló-Sastre E. Immunohistochemical analysis for neural
Zaffagnini S, Dejour D, Arendt EA, eds. Patellofemoral pain, instability, and arthritis. markers of the lateral retinaculum in patients with isolated symptomatic
Berlin: Springer, 2010:41–9. patellofemoral malalignment. A neuroanatomic basis for anterior knee pain in the
45 Fulkerson JP. A clinical test for medial patella tracking. Tech Orthop 1997;12:144. active young patient. Am J Sports Med 2000;28:725–31.
46 Sanchis-Alfonso V, Ramírez-Fuentes C, Montesinos-Berry E, et al. Femoral insertion 70 Vega J, Golanó P, Pérez-Carro L. Electrosurgical arthroscopic patellar denervation.
site of the graft used to replace the medial patellofemoral ligament influences the Arthroscopy 2006;22:1028.e1–3.
ligament dynamic changes during knee flexion as well as clinical outcome. Knee 71 Ho KY, Hu HH, Colletti PM, et al. Recreational runners with patellofemoral pain
Surg Sports Traumatol Arthrosc 2015 Dec 12 [Epub ahead of print] doi:10.1007/ exhibit elevated patella water content. Magn Reson Imaging 2014;32:965–8.
s00167-015-3905-0 72 Miltner O, Siebert CH, Schneider U, et al. Patellar hypertension syndrome in
47 Näslund JE, Odenbring S, Näslund UB, et al. Diffusely increased bone scintigraphic adolescence: a three-year follow up. Arch Orthop Trauma Surg 2003;123:
uptake in patellofemoral pain syndrome. Br J Sports Med 2005;39:162–5. 455–9.
48 Teitge RA, Faerber WW, Des Madryl P. Stress radiographs of the patellofemoral 73 Fulkerson JP, Becker GJ, Meaney JA, et al. Anteromedial tibial tubercle transfer
joint. J Bone Joint Surg Am 1996;78-A:193–203. without bone graft. Am J Sports Med 1990;18:490–6.
49 Biedert RM. Computed tomography examination. In: Biedert RM, ed. Patellofemoral 74 Tjoumakaris FP, Forsythe B, Bradley JP. Patellofemoral instability in athletes:
disorders. Diagnosis and treatment. West Sussex: Wiley, 2004:101–11. treatment via modified Fulkerson osteotomy and lateral release. Am J Sports Med
50 Crossley K, Bennell K, Green S. Physical therapy for patellofemoral pain: 2010;38:992–9.
a randomized, double-blinded, placebo-controlled trial. Am J Sports Med 75 Stevens PM, Gililland JM, Anderson LA, et al. Success of torsional correction surgery
2002;30:857–65. after failed surgeries for patellofemoral pain and instability. Strategies Trauma Limb
51 Cowan SM, Bennell KL, Crossley KM. Physical therapy alters recruitment of the vasti Reconstr 2014;9:5–12.
in patellofemoral pain syndrome. Med Sci Sports Exerc 2002;34:1879–85. 76 Gracitelli GC, Meric G, Pulido PA, et al. Fresh osteochondral allograft transplantation
52 Hodges PW, Mellor R, Crossley K, et al. Pain induced by injection of hypertonic for isolated patellar cartilage injury. Am J Sports Med 2015;43:879–84.
saline into the infrapatellar fat pad and effect on coordination of the quadriceps 77 Young NA, Sharma M, Deogaonkar M. Transcranial magnetic stimulation for chronic
muscles. Arthritis Rheum 2009;61:70–7. pain. Neurosurg Clin N Am 2014;25:819–32.
53 Amin S, Baker K, Niu J, et al. Quadriceps strength and the risk of cartilage loss and 78 Treister R, Lang M, Klein MM, et al. Non-invasive Transcranial Magnetic Stimulation
symptom progression in knee osteoarthritis. Arthritis Rheum 2009;60:189–98. (TMS) of the motor cortex for neuropathic pain-at the tipping point? Rambam
54 Segal NA, Glass NA, Torner J, et al. Quadriceps weakness predicts risk for knee Maimonides Med J 2013;29:e0023.
joint space narrowing in women in the MOST cohort. Osteoarthr Cartil 79 Franco CD, Buvanendran A, Petersohn JD, et al. Innervation of the anterior capsule
2010;18:769–75. of the human knee: implications for radiofrequency ablation. Reg Anesth Pain Med
55 Wang Y, Wluka AE, Berry PA, et al. Increase in vastus medialis cross-sectional area 2015;40:363–8.
is associated with reduced pain, cartilage loss, and joint replacement risk in knee 80 Leeuw M, Goossens ME, Linton SJ, et al. The fear-avoidance model of musculoskeletal
osteoarthritis. Arthritis Rheum 2012;64:3917–25. pain: current state of scientific evidence. J Behav Med 2007;30:77–94.
56 Faber M, Andersen MH, Sevel C, et al. The majority are not performing 81 Dixon KE, Keefe FJ, Scipio CD, et al. Psychological interventions for arthritis pain
home-exercises correctly two weeks after their initial instruction—an management in adults: a meta-analysis. Health Psychol 2007;26:241–50.
assessor-blinded study. Peer J 2015;3:e1102. 82 Chou R, Baisden J, Carragee EJ, et al. Surgery for low back pain: a review of the
57 Rathleff MS, Vicenzino B, Middelkoop M, et al. Patellofemoral pain in adolescence evidence for an American Pain Society Clinical Practice Guideline. Spine
and adulthood: same same, but different? Sports Med 2015;45:1489–95. 2009;34:1094–109.
58 Derasari A, Brindle TJ, Alter KE, et al. McConnell taping shifts the patella inferiorly 83 Zaffagnini S, Russo RL, Marcheggiani Muccioli GM, et al. The Videoinsight®
in patients with patellofemoral pain: a dynamic magnetic resonance imaging study. method: improving rehabilitation following anterior cruciate ligament reconstruction
Phys Ther 2010;90:411–19. —a preliminary study. Knee Surg Sports Traumatol Arthrosc 2013;21:851–8.

Sanchis-Alfonso V, et al. JISAKOS 2016;1:161–173. doi:10.1136/jisakos-2015-000033 173

 Downloaded from http://jisakos.bmj.com/ on October 4, 2016 - Published by group.bmj.com

Diagnosis and treatment of anterior knee pain

Vicente Sanchis-Alfonso, Jenny McConnell, Joan Carles Monllau and

John P Fulkerson

J ISAKOS 2016 1: 161-173 originally published online March 22, 2016

doi: 10.1136/jisakos-2015-000033

Updated information and services can be found at:

http://jisakos.bmj.com/content/1/3/161

These include:

References This article cites 74 articles, 20 of which you can access for free at:
http://jisakos.bmj.com/content/1/3/161#BIBL

Email alerting Receive free email alerts when new articles cite this article. Sign up in the
service box at the top right corner of the online article.

Notes

To request permissions go to:

http://group.bmj.com/group/rights-licensing/permissions

To order reprints go to:

http://journals.bmj.com/cgi/reprintform

To subscribe to BMJ go to:

http://group.bmj.com/subscribe/