See discussions, stats, and author profiles for this publication at: https://www.researchgate.

net/publication/42109107

Sutures versus staples for skin closure in orthopaedic surgery: meta-analysis

Article  in  BMJ (online) · March 2010

DOI: 10.1136/bmj.c1199 · Source: PubMed

CITATIONS READS

167 1,298

4 authors, including:

Toby Smith Charles J Mann

University of Oxford Norfolk and Norwich University NHS Trust and University of East Anglia
330 PUBLICATIONS   7,503 CITATIONS    18 PUBLICATIONS   528 CITATIONS   

SEE PROFILE SEE PROFILE

Simon T Donell
University of East Anglia
251 PUBLICATIONS   8,568 CITATIONS   

SEE PROFILE

Some of the authors of this publication are also working on these related projects:

Behaviour change physiotherapy intervention to increase physical activity following hip and knee replacement (PEP-TALK): View project

PERFECTED an NIHR programme grant to develop and test an enhanced recovery pathway for people with dementia who fracture their hip View project

All content following this page was uploaded by Simon T Donell on 01 June 2014.

The user has requested enhancement of the downloaded file.

 RESEARCH

Sutures versus staples for skin closure in orthopaedic

surgery: meta-analysis
Toby O Smith, research physiotherapist in orthopaedics, honorary lecturer Debbie Sexton, senior
orthopaedic physiotherapist Charles Mann, consultant orthopaedic surgeon Simon Donell, consultant
orthopaedic surgeon, honorary professor in musculoskeletal disorders

Norfolk and Norwich University ABSTRACT allocated methods of wound closure. Only one study had
Hospital, Norwich NR2 7UY Objective To compare the clinical outcomes of staples acceptable methodological quality.
Correspondence to: T O Smith
toby.smith@uea.ac.uk
versus sutures in wound closure after orthopaedic Conclusions After orthopaedic surgery, there is a
surgery. significantly higher risk of developing a wound infection
Cite this as: BMJ 2010;340:c1199 when the wound is closed with staples rather than
doi:10.1136/bmj.c1199
Design Meta-analysis.
Data sources Medline, CINAHL, AMED, Embase, Scopus, sutures. This risk is specifically greater in patients who
and the Cochrane Library databases were searched, in undergo hip surgery. The use of staples for closing hip or
addition to the grey literature, in all languages from 1950 knee surgery wounds after orthopaedic procedures
to September 2009. Additional studies were identified cannot be recommended, though the evidence comes
from cited references. from studies with substantial methodological limitations.
Though we advise orthopaedic surgeons to reconsider
Selection criteria Two authors independently assessed
their use of staples for wound closure, definitive
papers for eligibility. Included studies were randomised
randomised trials are still needed to assess this research
and non-randomised controlled trials that compared the
question.
use of staples with suture material for wound closure after
orthopaedic surgery procedures. All studies were
INTRODUCTION
included, and publications were not excluded because of
With the development of accelerated rehabilitation
poor methodological quality.
and the pressures placed on surgeons to reduce lengths
Review methods Two authors independently reviewed of stay in hospital, the method of skin closure has
studies for methodological quality and extracted data become increasingly important in orthopaedic
from each paper. Final data for analysis were collated surgery.1 2 Wound complications are one of the major
through consensus. The primary outcome measure was sources of morbidity after orthopaedic procedures and
the assessment of superficial wound infection after can prolong the inpatient stay or lead to re-admission.2
wound closure with staples compared with sutures. The objective of good wound closure is rapid skin heal-
Relative risk and mean difference with 95% confidence ing and an acceptable cosmetic result while minimising
intervals were calculated and pooled with a random the risks of complications such as wound dehiscence or
effects model. Heterogeneity was assessed with I2 and χ2 infection.3 4 Such complications have a considerable
statistical test. impact on the recovery of the patient, causing
Results Six papers, which included 683 wounds, were increased morbidity, delayed discharge, increased
identified; 332 patients underwent suture closure and costs, and reduced satisfaction.3 4 There is also a link
351 staple closure. The risk of developing a superficial between superficial wound infection and deep (pros-
wound infection after orthopaedic procedures was over thetic) infection.5
three times greater after staple closure than suture The most commonly used methods for skin closure
closure (relative risk 3.83, 95% confidence interval 1.38 after orthopaedic surgery are metal staples or nylon
to 10.68; P=0.01). On subgroup analysis of hip surgery sutures.1 3 Both methods act to hold the skin edges
alone, the risk of developing a wound infection was four together while healing occurs. Metal staples are said
times greater after staple closure than suture closure to be superior as they are regarded as quicker and
(4.79, 1.24 to 18.47; P=0.02). There was no significant easier than sutures.6-8 Other authors have suggested
difference between sutures and staples in the that use of metal staples or clips has a greater risk of
development of inflammation, discharge, dehiscence, wound infection4 and might be less acceptable cosme-
necrosis, and allergic reaction. The included studies had tically than sutures.2 Metal staples might also be more
several major methodological limitations, including the expensive.2 9 10
recruitment of small, underpowered cohorts, poorly Some authors have compared the clinical outcomes
randomising patients, and not blinding assessors to the of wound closure with staples and sutures after
BMJ | ONLINE FIRST | bmj.com page 1 of 8
 RESEARCH

orthopaedic surgery. The optimal method of skin clo- insufficient information on population characteristics,
sure still remains unclear.2 11 We reviewed the evidence surgical procedure, or outcomes.
base systematically and conducted a meta-analysis. We Study identification—Two authors (TOS, DS) inde-
examined whether there is a difference in clinical out- pendently screened all titles and abstracts identified
comes with staples or sutures in orthopaedic wound from the search strategy. The full texts for all poten-
closure in adult patients. tially eligible studies that seemed to follow the selection
criteria were ordered. These were then reviewed by
METHODS each of the two independent reviewers again for elig-
Data sources—We searched AMED (1985 to July 2009), ibility against the predefined criteria.
British Nursing Index (1985 to July 2009), CINHAL Data extraction—The two reviewers (TOS, DS) then
(1982 to July 2009), Embase (1974 to July 2009), and independently reviewed each eligible paper. Each
Medline (1950 to July 2009) via Ovid. We also reviewer extracted data on a predefined database. The
searched Scopus and the Cochrane Library. Details two databases were then compared. Data collected from
of the MeSH terms and keywords and the Boolean each paper included number of patients and operations,
operators adopted can be found in the appendix on age, sex, operative procedure, closure method, grade of
bmj.com. Unpublished literature was also assessed surgeon, antibiotic cover, and dressing applied as well
with the search terms “closure” AND “hip” from the as data on the incidence of wound infection, dehiscence,
databases SIGLE (System for Information on Grey Lit- inflammation, discharge, necrosis, abscess formation,
erature in Europe), the National Technical Informa- allergic reactions, length of stay in hospital, closure
tion Service, the National Research Register (UK), time, and patients’ satisfaction and pain.
and the Current Controlled Trials databases. Once Critical appraisal—Each reviewer (TOS, DS) criti-
we had gathered all relevant full text papers we cally appraised each study using the Physiotherapy
reviewed each reference list for any omitted studies. Evidence Database (PEDro) critical appraisal tool.
Finally, we contacted corresponding authors of papers This is an 11 item scoring system, which is reliable
to identify any publications that had not been pre- and valid in the assessment of randomised controlled
viously highlighted through the search strategies. A trials.12 13 Any disagreements regarding study selec-
review protocol for this meta-analysis was not pub- tion, data extraction, or appraisal score were resolved
lished or registered before we undertook this study. through discussion.
Eligibility criteria—We included all full text rando- Outcome measures—Our primary outcome was the
mised and non-randomised clinical trials comparing incidence of wound infection after skin staples com-
the outcomes of wound closure with skin staples or pared with suture closure after orthopaedic surgery.
suture after orthopaedic surgery, comprising any The secondary outcomes under investigation included
orthopaedic operative procedure including trauma the incidence of wound dehiscence, inflammation, dis-
and elective procedures. We excluded papers asses- charge, necrosis, abscess formation, allergic reactions,
sing the effects of synthetic adhesives such as 2-octyl length of stay, closure time, and patients’ satisfaction
cyanoacrylate and editorials, comments, or letters and pain.
based on methodological quality. We also excluded Statistical analysis—One author (TOS) conducted all
cadaveric or animal studies, citations that did not statistical analyses using Review Manager 5.0 (Nordic
adhere to our study criteria, and studies that provided Cochrane Centre, Cochrane Collaboration 2009,
Copenhagen, Denmark). When we found no evidence
of a substantial difference in study populations, inter-
ventions, or outcome measurements, we carried out a
Identification
meta-analysis. We assessed statistical heterogeneity
Records identified through Additional records identified
database searching (n=194) through other sources (n=0)
with χ2 and I2. In each analysis, if χ2heterogeneity was
reported as P>0.05, and the I2 statistic indicated that het-
Screening erogeneity was low (<20%),14 we used a fixed effect
Records after duplicates removed (n=83) model to calculate the total relative risk ratio or mean
difference and 95% confidence interval. Otherwise we
Records screened (n=83) Records excluded (n=66) used a random effects model. After this, we used the
Eligibility mean pooled difference to assess for continuous data,
Full text articles assessed for eligibility (n=17) Full text articles excluded (n=11): while pooled relative risk ratios were assessed for all
Unable to directly comparing suture to staple dichotomous data with the Mantel-Haenszel method.15
cohorts (n=8)
Unable to differentiate results of orthopaedic
A probability of P<0.05 was determined as significant,
to non-orthopaedic cases (n=3) and 95% confidence intervals were also calculated. Sub-
Included group analyses were prespecified before data collection
Studies included in qualitative synthesis (n=6)
to compare the results separately of skin staples and
sutures in hip, knee, spinal, and upper extremity proce-
Studies included in meta-analysis (n=6) dures. When insufficient data were presented in the full
text publication, we attempted to contact all correspond-
Fig 1 | Flow of identified studies ing authors. Finally, we used a funnel plot to test for
page 2 of 8 BMJ | ONLINE FIRST | bmj.com
 RESEARCH

Meta-analysis

SE (log(relative risk))
0
All orthopaedic procedures
0.5 Six outcomes could be assessed with meta-analysis.
The risk of a wound infection was over three times
greater with staples than with sutures (P=0.01; fig 3).
1.0
There was no significant difference in the relative risk
of wound discharge, inflammation, necrosis, dehis-
1.5
cence, or allergic reaction (P>0.05; table 2). Only the
assessment of wound inflammation exhibited substan-
2.0
0.01 0.1 1 10 100 tial statistical heterogeneity (I2=85%).
In the study by Stockley and Elson10 a higher pro-
Relative risk
portion of patients reported considerable pain with
Fig 2 | Publication bias funnel plot for incidence of wound removal of staples compared with the proportion
infection after orthopaedic surgery who did so with removal of sutures. This was not
assessed with inferential statistics.
potential publication bias for the outcome measure that Only Singh et al assessed the cost effectiveness of the
was most commonly presented in the papers reviewed. two methods of wound closure.2 They reported that the
use of staples was three times more expensive than sub-
RESULTS cuticular vicryl sutures, when the staple applicator and
Systematic review remover were taken into account. They reported that
The search retrieved 194 records of possible relevance. this would be a difference of about £1m (€1.1m, $1.5m)
Of these, six adhered to the predefined selection cri- a year, based on the incidence of about 750 000 frac-
teria and were included in the review. Figure 1 shows tures of the neck of the femur each year.
the results of the search strategy. The assessment of Khan et al compared length of stay in hospital and
publication bias with frequency of wound infection in patients’ satisfaction between wound closure methods
all orthopaedic procedures indicated no substantial in their patients undergoing hip and knee surgery.1
evidence of publication bias (fig 2). 16 Only one study They found no significant difference between methods
had acceptable methodological quality. in the two groups (P>0.05). They did, however, report
that wound closure was significantly faster with staples
Population characteristics than with sutures (P<0.05) and that there was no signif-
In total, 683 patients were included in this review; 332 icant difference in cosmesis according to the Hollander
patients underwent suture closure and 351 staple clo- wound evaluation score.18 Finally, two patients devel-
sure. Four studies provided data on sex1 2 4 17; there oped wound abscesses, one after total knee replace-
were 60 men and 131 women in the suture group and ment and one after total hip replacement.1 In both
57 men and 117 women in the staple group. Table 1 cases closure was with sutures.
shows that three studies assessed the outcomes after hip
surgery, 2 4 17 two studies assessed a mixture of hip and Hip surgery
knee arthroplasty patients, 1 10 and one study assessed Five studies provided data on methods of wound clo-
outcomes after upper and lower limb trauma surgery. 9 sure after hip surgery.1 2 4 10 17 Four outcomes were
In the three papers that provided relevant information, appropriate to assess with meta-analysis. The risk of a
the mean age was 79.7 (SD 3.7) in the suture group and wound infection was over four times greater in those
81.6 (SD 5.0) in the staple group. Routine antibiotics cases where the wounds were closed with staples than
were administered in four studies. 1 2 10 17 The time for with sutures (P=0.02; fig 4). There was no significant
suture or staple removal ranged from 10 days to difference between the incidence of wound discharge,
16 days. The mean follow-up period was 95 days (SD dehiscence, or allergic reaction between the two meth-
136.9). ods after hip surgery (P>0.05; table 3).

Table 1 | Details of included papers comparing methods of wound closure after orthopaedic surgery
Mean age Time to
Wounds (years) Sex removal Follow-
Operation Closure material Suture Staple Suture Staple Suture Staple (days) up (days)
Clayer and THR, hip fracture surgery Subcuticular polypropylene; 33 33 75.4 75.9 11/22 10/23 10-14 84
Southwood17 skin staples
Khan et al1 THR, TKR Absorbable suture; skin staples 64 63 NS NS 3331 3033 10 84
Murphy et al9 ORIF ankle, tibia, patella, femur, Nylon suture; clips 29 31 NS NS NS NS 13 13
forearm, olecranon, humerus
Shetty et al4 Hip fracture surgery Subcuticular vicryl; metallic skin 47 54 81.7 83.5 740 1341 10 10
staples
Singh et al2 Hip fracture surgery Subcuticular vicryl; clips 30 41 82 85.4 624 734 10 14
Stockley and Elson10 THR, hip and knee ORIF, TKR Nylon suture; skin staples 129 129 NS NS NS NS 10-16 365
THR=total hip replacement, TKR=total knee replacement, NS=not stated, ORIF=open reduction internal fixation.

BMJ | ONLINE FIRST | bmj.com page 3 of 8

 RESEARCH

Table 2 | Outcomes of suture compared with staple wound closure in orthopaedic surgery
Incidence Heterogeneity
Suture Staple Relative risk (95% CI) Overall effect (P value) I2 (%) χ2 P value
Discharge1 2 9 8/124 17/134 1.54 (0.31 to 7.80) 0.60 59 0.09
Inflammation2 9 3/60 22/71 4.69 (0.08 to 269.80) 0.46 85 0.01
Infection1 2 4 9 10 17 3/333 17/350 3.83 (1.38 to 10.68) 0.01 0 0.76
Wound necrosis9 10 1/158 3/160 2.26 (0.34 to 14.88) 0.40 0 0.41
Dehiscence2 4 9 17 1/140 5/158 2.30 (0.54 to 9.84) 0.26 0 0.90
Allergic reaction1 10 1/193 1/192 1.01 (0.14 to 7.12) 0.99 0 0.99

Two studies assessed wound cosmesis. Clayer and Critical appraisal

Southwood17 reported that the scars produced by Critical appraisal of the six included studies showed
suture closure were significantly thinner than with sta- considerable variation in methodological quality
ples after hip surgery (P<0.05). Khan et al, however, (table 4). Only half of the studies were randomised
reported no significant difference between wound clo- controlled trials. Khan et al 1 and Shetty et al 4 con-
sure method and the Hollander wound evaluation cealed allocation to limit allocation bias. Only half of
score after hip surgery (P>0.05).1 the studies tested baseline comparability to ensure that
the two groups were equal before wound closure. 1
Knee surgery Similarly, only one study blinded participants and
Two studies were identified compared the outcomes of assessors to the method of wound closure by covering
sutures with staples after knee surgery.1 10 Only the the wound with a dressing, in an attempt to limit asses-
incidence of wound infection could be assessed with a sor bias. While all studies except Stockley and Elson 10
meta-analysis. This suggested that there was no signifi- compared the results of their two groups using inferen-
cant difference between the groups after knee surgery tial statistics, only Khan et al 1 and Murphy et al 9 fol-
(P=0.20; table 3). As in hip surgery, there was no sig- lowed intention to treat principles in data analysis.
nificant difference in the Hollander wound evaluation Furthermore, Khan et al 1 presented their results
score between suture compared with staple closure using confidence intervals.
after knee surgery (P>0.05).
DISCUSSION
Spinal surgery After orthopaedic surgery, there is a greater risk of
We did not find any studies that examined outcomes of wound infection in patients whose wounds are closed
wound closure with sutures compared with staples with metallic staples than with sutures. Our meta-ana-
after spinal surgery. lysis showed no significant difference between the two
closure methods with respect to wound discharge,
Upper limb inflammation, necrosis, dehiscence, or allergic reac-
Only one study was identified that examined the out- tion. We consider, however, that only one study had
comes of wound closure with sutures compared with acceptable methodological quality.1 The remaining
staples after surgery to the forearm, olecranon, and evidence base presented considerable methodological
humerus.9 The results were not presented indepen- limitations, including not justifying sample sizes based
dently from those for lower limb surgery. It was there- on a power calculation, poorly blinding patients and
fore not possible to determine whether there was a assessors to the method of wound closure, not ade-
difference in outcome between these two methods of quately following up patients over a reasonable period
wound closure in orthopaedic procedures in upper of time, and poorly detailing the allocation method to
limbs compared with lower limbs. the two groups. While it might be difficult to blind
assessors to the method of wound closure, particularly
Study Staples Sutures Fixed risk ratio Weight Fixed risk ratio within the initial postoperative month, blinding of
(95% CI) (%) (95% CI) patients is logistically possible. Accordingly, such lim-
Clayer and Southwood17 1/33 1/33 21.6 1.00 (0.07 to 15.33) itations should be considered in the design of future
Khan et al1 6/63 1/64 21.5 6.10 (0.76 to 49.19) studies to improve the evidence base.
Murphy et al9 1/31 1/29 22.4 0.94 (0.06 to 14.27)
Shetty et al4 5/54 0/47 11.6 9.60 (0.54 to 169.16) Comparison with other studies
Singh et al2 3/40 0/31 12.2 5.46 (0.29 to 102.00) Factors that have been cited as important in the choice
Stockley and Elson10 1/129 0/129 10.8 3.00 (0.12 to 72.96) of wound closure after orthopaedic surgery have
Total (95% CI) 17/350 3/333 100.0 3.83 (1.38 to 10.68) included the ease and speed of closure, the level of
Test for heterogeneity: χ2=2.62, df=5, P=0.76, I2=0% patients’ discomfort, the complication rate, the final
Test for overall effect: z=2.57, P=0.01 0.01 0.1 1 10 100 cosmetic result, and the cost.2 Early studies had sug-
Favours Favours gested that the incidence of wound infection might be
staples sutures
reduced with staples because of the mechanism of fixa-
Fig 3 | Incidence of infection for wounds closed with sutures or staples tion. Johnson et al19 and Stillman et al20 suggested that
page 4 of 8 BMJ | ONLINE FIRST | bmj.com
 RESEARCH

Study Staples Sutures Fixed risk ratio Weight Fixed risk ratio Previous studies have examined the clinical outcomes
(95% CI) (%) (95% CI)
of skin closure with continuous or subcuticular inter-
Clayer and Southwood17 1/33 1/33 38.2 1.00 (0.07 to 15.33) rupted suture techniques for repair of episiotomy or sec-
Khan et al1 3/36 0/33 19.9 6.43 (0.34 to 120.03) ond degree perineal tears23-25 and vascular surgery.26 27
Shetty et al4 5/54 0/47 20.4 9.60 (0.54 to 169.16) Most orthopaedic studies used interrupted subcuticular
Singh et al2 3/40 0/31 21.5 5.46 (0.29 to 102.00) suture techniques for wound closure, while only two
Total (95% CI) 12/163 1/144 100.0 4.79 (1.24 to 18.47) studies adopted a continuous suture technique.9 10
Test for heterogeneity: χ2=1.54, df=3, P=0.67, I2=0% There were no substantial differences in the trends in
Test for overall effect: z=2.28, P=0.02 0.01 0.1 1 10 100 results between these two studies and the other studies
Favours Favours included in this review As this has yet to be empirically
staples sutures
studied, it is therefore unclear whether the method of
Fig 4 | Incidence of infection for hip wounds closed with sutures or staples suture closure is a confounding variable with respect
to the rate of complications, the patients’ reported satis-
skin stapling might cause less damage to the wound’s faction for cosmetic results, and the discomfort reported
defences than non-absorbable sutures. This was based through the removal of suture material.
on the principle that the presence of a foreign material Graham et al28 proposed that deposition of wound
might compromise the immune response. Further- collagen is directly related to wound oxygenation and
more, Pickford et al suggested that as staples do not perfusion.29 30 They reported more favourable blood
penetrate the incision but cross the incision site, this perfusion characteristics in wounds closed with staples
might prevent the introduction of foreign material.21 rather than sutures, in addition to a significantly higher
Our findings, however, suggested the contrary— blood contact in the wound at seven days compared
namely, that wounds closed with staples rather than with the suture group (P=0.02).28 We found that the
sutures have four times the risk of infection. Whether incidence of wound infection was greater with staples
this is a consequence of the clip being metallic rather than with sutures. Therefore, our findings do not con-
than vicryl or nylon material or whether the tension firm those of Graham et al,28 as oxygen perfusion might
developed through a mattress suture closure is super- be associated with wound infection and necrosis. The
ior to that of staples in reducing the incidence of open- influence of oxygen perfusion in hip wounds and knee
ing the wound during mobilisation remains unclear. wounds, which was assessed in the study of Graham et
Our conclusion was reached, however, after applica- al,28 remains unclear.
tion of the statistical method for the whole evidence Murphy et al suggested that poor results with staples
base and was significant for hip surgery but not knee were attributable to poor technique in staple
surgery. The rationale for this has been postulated by placement.9 The accuracy of suture or staple closure
Khan et al,1 who pointed out that knee wounds are con- and choice of closure method can have an effect on
siderably longer than hip wounds and are subjected to the accuracy of coaptation of the dermal margins.
more mobility as they are covered by less tissue. As Poor technique can lead to suboptimal healing.10 This
only 88 patients have been assessed in relation to might cause oozing wound edges and delay in healing
knee wound closure with staples compared with and increase the potential for infection.8 9 Superficial
sutures, this observation remains underpowered at infection in hip and knee arthroplasty is a worrying
present. clinical sign because of the risk of the infection spread-
It remains unclear as to whether there was a differ- ing through the dermal layers to the implant. With the
ence in cosmetic result between wounds closed with increased pressure on surgical time, and the advances
sutures or staples after orthopaedic surgery.1 17 As the in non-medical staff taking extended roles in wound
present included studies did not analyse the results closure, such considerations might be important
based on different comorbidities, age, or skin type, when considering outcomes within each institution.
we do not know whether patients with difference skin Metal staples have been regarded as a more expen-
types might present with differing outcomes—for sive option for wound closure,9 10 though costs could be
example, Afro-Caribbean patients are more suscepti- reduced by reduced theatre time and ease of clip
ble to hypertrophic and keloid scarring.22 removal compared with suturing wounds. This might

Table 3 | Outcomes of suture compared with staple wound closure in hip and knee surgery
Incidence Heterogeneity
Suture Staple Relative risk (95% CI) Overall effect (P value) I2 (%) χ2 P value
Hip surgery
Discharge1 2 2/64 13/76 3.85 (0.27 to 54.00) 0.32 62 0.10
Infection1 2 4 17 1/144 12/163 4.79 (1.24 to 18.47) 0.02 0 0.67
Dehiscence2 4 17 0/111 4/127 3.19 (0.53 to 19.18) 0.21 0 0.98
Allergic reaction1 10 1/132 1/135 0.96 (0.14 to 6.58) 0.97 0 0.32
Knee surgery
Infection1 10 1/61 4/57 3.29 (0.54 to 20.04) 0.20 0 0.94

BMJ | ONLINE FIRST | bmj.com page 5 of 8

 RESEARCH

Table 4 | PEDro critical appraisal results showing whether each study satisfied criteria
Clayer and
Southwood17 Khan et al1 Murphy et al9 Shetty et al4 Singh et al2 Stockley et al10
Eligibility criteria Yes Yes No No No No
Random allocation No Yes Yes Yes No No
Concealed allocation No Yes No Yes No No
Baseline comparability Yes Yes No No Yes No
Blinded patient No Yes No No No No
Blinded clinician No No No No No No
Blinded assessor No Yes No No No No
Adequate follow-up Yes No No No No Yes
Intention to treat analysis No Yes Yes No No No
Between group analysis Yes Yes Yes Yes Yes No
Point estimates and variability Yes Yes Yes No No No
Total score 5 9 4 3 2 1

prove to be false economy, however, as the conse- compared with staples.40 Finally, a systematic review
quences of a deep infection for the patient are substan- of methods of skin closure in caesarean section
tial through the increased costs associated with medical reported that use of absorbable subcuticular sutures
care and admission to hospital.31 Furthermore, as the resulted in less postoperative pain and yielded a better
number of dressing changes was greater in those who cosmetic result than staples.41 While there seems to be
underwent skin stapling, and as a specific staple consensus that staple closure is faster than suture clo-
remover is required, the overall cost of the staples sure, there remains some variation between studies for
and applicator is mitigated by savings in dressing cosmetic results and pain outcomes. There seemed to
costs. Although Singh et al estimated the cost effective- be no significant difference in complication rates,
ness of these two closure methods,2 no formal cost-ben- including wound infection, between caesarean wounds
efit analysis has been undertaken. closed with sutures compared with staples, contrary to
One study assessed patients’ satisfaction1 and our findings. By re-evaluating this issue with well
reported no significant difference between the designed randomised controlled trials it will be possi-
groups.1 Stockley and Elson10 and Singh et al2 reported ble to compare the findings of orthopaedic to other
that staples were invariably more painful to remove surgical procedures.
than sutures. The relative discomfort of staple removal
compared with suture removal has been previously Strengths and limitations
cited in the non-orthopaedic literature.32-34 Secondly, We found no significant difference in the presentation
some authors have suggested that there might be of inflammation for wounds closed with sutures rather
greater satisfaction for surgeons in using staples than than staples, which was unexpected given the differ-
sutures. The time saving benefits of staples might ences exhibited between methods for infection. This
have a psychological effect on surgeons and theatre outcome, however, was assessed in only two studies
staff, particular after a long operation.9 10 35 Given the with small cohorts so the lack of a statistical difference
difference in the incidence of superficial wound infec- might have been because of type II statistical error.42
tion, and the limited empirical evidence for patients’ or We also noted considerable heterogeneity, possibly as
surgeons’ preference for staple closure, there is insuffi- a consequence of the small number of patients
cient evidence to justify the use of staples over sutures. reviewed, so it might be inappropriate to use these
Our findings can be directly generalised only to results based on the current pooled analysis. Further
orthopaedic hip and knee arthroplasty surgery. Differ- study of the effect of inflammation as an outcome
ent methods of skin closure, however, have been with large sufficiently powerful samples is therefore
assessed in other surgical procedures, such as scalp indicated to assess whether this outcome measure dif-
lacerations. While stapling has been shown to be faster fers between orthopaedic wounds closed with sutures
and less expensive than suturing in the repair of compared with staples.
uncomplicated scalp lacerations in children and adults, A major limitation within the literature was that
no differences in complication rates, including infec- none of the studies differentiated between superficial
tion, have been shown.36-38 Similarly, there was no sig- and deep wound infections in their results. While
nificant difference in complications after abdominal superficial wound infections might be problematic for
wound closure.39 In this specific population, however, the patient, these will usually resolve with antibiotics.
stapling resulted in poorer cosmetic scores than sutur- In contrast, a deep wound infection has a considerably
ing in transverse abdominal wounds.39 Ranaboldo and greater impact, particularly in arthroplasty surgery,
Rowe-Jones reported that wound pain and require- and requires extensive debridement, wound wash-
ment for analgesia was significantly lower in patients out, prosthesis revision surgery, and, potentially,
whose laparotomy wounds were closed with sutures amputation.
page 6 of 8 BMJ | ONLINE FIRST | bmj.com
 RESEARCH

greater risk of wound infection than traditional sutur-

WHAT IS ALREADY KNOWN ON THIS TOPIC
ing. Given the methodological limitations identified,
Orthopaedic surgeons use both metallic staples and nylon sutures to close wounds definitive randomised trials are needed to re-appraise
Controversy exists as to the best method of wound closure after orthopaedic procedures such this research question. With the current evidence, how-
as lower limb joint arthroplasty, reconstructive surgery, and trauma fixation ever, patients and doctors should think more carefully
about the use of staples for wound closure after hip and
WHAT THIS STUDY ADDS knee surgery.
In orthopaedic surgery the risk of infection after staple closure was three times the risk with We thank staff at the Sir Thomas Browne Library at the Norfolk and
suture closure; after hip surgery the risk was four times greater Norwich University Hospital for their assistance in obtaining the texts that
formed the basis of this review. We also thank Richard Haywood,
To minimise wound infection, orthopaedic surgeons should close wounds with sutures rather consultant plastic surgeon, Norfolk and Norwich University Hospital, for
than staples his surgical advice during the writing of this paper.
Only one of the studies included in the meta-analysis was of acceptable methodological Contributors: TOS and DS assisted in the conception and design, analysis
and interpretation of data, and drafting of the article and its revision. CM
quality
and SD assisted in the analysis and interpretation of data and in the
drafting the article and its revision. All authors consider and approved of
the final version of this report to be published. TOS is guarantor.
The evidence base poorly presented important Funding: This research received no specific grant from any funding agency
demographic details for their cohorts. For example, in the public, commercial, or not-for-profit sectors.
Competing interests: None declared.
only three studies provided data on patients’ age. Ethical approval: Not required.
Accordingly, we could not assess whether this was an Data sharing: Technical appendix, statistical code, and dataset available
important variable between the two groups. Similarly, from the corresponding author at toby.smith@uea.ac.uk.
the studies poorly presented details regarding patients’
medical history, use of steroids, weight, and body mass 1 Khan RJK, Fick D, Yao F, Tang K, Hurworth M, Nivbrant B, et al. A
comparison of three methods of wound closure following
index, which might also have been confounding vari- arthroplasty. A prospective, randomised controlled trial. J Bone Joint
ables. Propensity scoring methods would compensate Surg 2006;88-B:238-42.
for potential differences in important characteristics.43 2 Singh B, Mowbray MAS, Nunn G, Mearns S. Closure of hip wound,
clips or subcuticular sutures: does it make a difference? Eur J Orthop
As only Khan et al1 and Shetty et al4 concealed patient Surg Traumatol 2006;16:124-9.
allocation, allocation bias might have affected findings 3 Livesey C, Wylde V, Descamps S, Estela CM, Bannister GC,
Learmonth ID, et al. Skin closure after total hip replacement: a
because the patient’s clinical presentation might have randomised controlled trial of skin adhesive versus surgical staples. J
influenced the surgeon’s choice of methods before ran- Bone Joint Surg 2009;91-B:725-9.
domisation. Concealed randomisation should there- 4 Shetty AA, Kumar VS, Morgan-Hough C, Georgeu GA, James KD,
Nicholl JE. Comparing wound complication rates following closure of
fore be considered in the design of future research to hip wounds with metallic skin staples or subcuticular vicryl suture: a
prevent such bias. prospective trial. J Orthop Surg 2004;12:191-3.
5 Saleh K, Olson M, Resig S, Bershadsky B, Kuskowski M, Gioe T, et al.
Only the study of Khan et al can be judged as meth- Predictors of wound infection in hip and knee joint replacement:
odologically well designed and appropriately results from a 20 year surveillance program. J Orthop Res
reported.1 The remaining papers reviewed had consid- 2002;20:506-15.
6 Carcoforo P, Navarra G, Gasbarro V, Occhionorelli S, Fabbri N,
erable limitations. Given that Khan et al’s cohort con- Sartoni A, et al. Cutaneous mechanical staplers: our experience.
stituted 19% of the total meta-analysis cohort,1 the Minerva Chir 1997;52:1009-13.
7 Chughtai T, Chen LQ, Salasidis G, Nguyen D, Tchervenkov C, Morin JF.
weaker studies might have considerably affected our Clips versus suture technique: is there a difference? Can J Cardiol
results. Accordingly, we recommend that further well 2000;16:1403-7.
designed randomised controlled trials are conducted 8 Meiring L, Cilliers K, Barry R, Nel CJ. A comparison of a disposable
skin stapler and nylon sutures for wound closure. S Afr Med J
to further examine the results of this meta-analysis. 1982;62:371-2.
After this, orthopaedic surgeons will then be able to 9 Murphy M, Prendergast P, Rice J. Comparison of clips versus sutures
justify their use of closure method by using a more rig- in orthopaedic wound closure. Eur J Orthop Surg Trauamtol
2004;14:16-8.
orous evidence base than is currently available. 10 Stockley I, Elson RA. Skin closure using staples and nylon sutures: a
Finally, nearly all identified papers compared the out- comparison of results. Ann Roy Coll Surg Eng 1987;69:76-8.
11 Singhal AK, Hussain A. Skin closure with automatic stapling in total
come of method of wound closure in hip surgery. We hip and knee arthroplasty. JK Practitioner 2006;13:142-3.
did not find any studies assessing the effect of different 12 Foley NC, Bhogal SK, Teasell RW, Bureau Y, Speechley MR. Estimates
methods in spinal surgery, only one study was identified of quality and reliability with the physiotherapy evidence-based
database scale to assess the methodology of randomized controlled
on the effects of knee surgery, and only Murphy et al’s trials of pharmacological and nonpharmacological interventions.
study included patients who had undergone upper limb Phys Ther 2006;86:817-24.
13 Maher CG, Sherrington C, Herbert RD, Moseley AM, Elkins M.
surgery.9 The limited evidence, particularly in upper Reliability of the PEDro scale for rating quality of randomized
limb surgery, might reflect a predominance of suture controlled trials. Phys Ther 2003;83:713-21.
closure after elbow, wrist, and hand surgery. The clini- 14 Higgins JPT, Thompson SG, Deeks JJ, Altman DG. Measuring
inconsistency in meta-analyses. BMJ 2003;327:557-60.
cal justification for this might be on ease of sutured clo- 15 Mantel N, Haenszel, W. Statistical aspects of the analysis of data
sure compared with staples in hand surgery or on an from retrospective studies of disease. J Natl Cancer Inst
1959;22:719-48.
improved cosmetic result with sutures.
16 Egger M, Davey SG, Schneider M, Minder C. Bias in meta-analysis
detected by a simple, graphical test. BMJ 1997;315:629-34.
Conclusions and policy implications 17 Clayer M, Southwood RT. Comparative study of skin closure in hip
surgery. Aust N Z J Surg 1991;61:363-5.
Use of metal clips to close orthopaedic wounds, most 18 Hollander JE, Singer AJ, Valentine S, Henry MC. Wound registry:
notably in hip surgery, is associated with a significantly development and validation. Ann Emerg Med 1995;25:675-85

BMJ | ONLINE FIRST | bmj.com page 7 of 8

 RESEARCH

19 19Johnson A, Rodeheaver GT, Durand LS, Edgerton MT, Edlich RF. 31 Edwards C, Counsell A, Boulton C, Moran CG. Early infection after hip
Automatic disposable stapling devices for wound closure. Ann fracture surgery: risk factors, costs and outcome. J Bone Joint Surg
Emerg Med 1981;10:631-5. 2008;90-B:770-7.
20 20Stillman RM, Bella FJ, Seligman SJ. Skin wound closure. Arch Surg 32 Frishman GN, Schwartz T, Hogan JW. Closure of Pfannenstiel skin
1980;115:674-5. incisions. Staples vs subcuticular suture. J Reprod Med
1997;42:627-30.
21 Pickford IR, Brennan SS, Evans M, Pollock AV. Two methods of skin
closure in abdominal operations: a controlled clinical trial. Br J Surg 33 Reed MR, Lennard TW. Prospective randomized trial of clips versus
1983;70:226-8. subcuticular polydioxamone for neck wound closure. Br J Surg
1997;84;118.
22 Brown JJ, Ollier W, Arscott G, Ke X, Lamb J, Day P, et al. Genetic
34 Selvadurai D, Wildin C, Treharne G, Choksy SA, Heywood MM,
susceptibility to keloid scarring: SMAD gene SNP frequencies in Afro-
Nicholson ML. Randomised trial of subcutaneous suture versus
Caribbeans. Exp Dermatol 2008;17:610-3.
metal clips for wound closure after thyroid and parathyroid surgery.
23 Valenzuela P, Saiz Puente MS, Valero JL, Azorín R, Ortega R, Ann R Coll Surg Eng 1997;79;303-6.
Guijarro R. Continuous versus interrupted sutures for repair of 35 Gatt D, Quick CR, Owen-Smith MS. Staples for wound closure: a
episiotomy or second-degree perineal tears: a randomised controlled trial. Ann R Coll Surg Engl 1985;67:318-20.
controlled trial. BJOG 2009;116:436-41. 36 Kanegaye JT, Vance CW, Chan L, Schonfeld N. Comparison of skin
24 Kettle C, Hills RK, Ismail KMK. Continuous versus interrupted sutures stapling devices and standard sutures for pediatric scalp lacerations:
for repair of episiotomy or second degree tears. Cochrane Database a randomized study of cost and time benefits. J Pediatr
Syst Rev 2009;(4):CD000947. 1997;130:808-13.
25 Kindberg S, Stehouwer M, Hvidman L, Henriksen TB. Postpartum 37 Khan AN, Dayan PS, Miller S, Rosen M, Rubin DH. Cosmetic outcome
perineal repair performed by midwives: a randomised trial of scalp wound closure with staples in the pediatric emergency
comparing two suture techniques leaving the skin unsutured. BJOG department: a prospective, randomized trial. Pediatr Emerg Care
2008;115:472-9. 2002;18:171-3.
26 Murphy PG, Tadros E, Cross S, Hehir D, Burke PE, Kent P, et al. Skin 38 Ritchie AJ, Rocke LG. Staples versus sutures in the closure of scalp
closure and the incidence of groin wound infection: a prospective wounds: a prospective, double-blind, randomized trial. Injury
study. Ann Vasc Surg 1995;9:480-2. 1989;20:217-8.
39 Lubowski D, Hunt D. Abdominal wound closure comparing the
27 Angelini GD, Butchart EG, Armistead SH, Breckenridge IM.
proximate stapler with sutures. Aust N Z J Surg 1985;55:405-6.
Comparative study of leg wound skin closure in coronary artery
bypass graft operations. Thorax 1984;39:942-5. 40 Ranaboldo CJ, Rowe-Jones DC. Closure of laparotomy wounds: skin
staples versus sutures. Br J Surg 1992;79:1172-3.
28 Graham DA, Jeffery JA, Bain D, Davis P, Bentley G. Staple vs
41 Alderdice F, McKenna D, Dornan J. Techniques and materials for skin
subcuticular vicryl skin closure in knee replacement surgery: a
closure in caesarean section. Cochrane Database Syst Rev
spectrophotographic assessment of wound characteristics. Knee
2003;(2):CD003577.
2000;7:239-43.
42 Bland M. An introduction to medical statistics. 3rd ed. Oxford
29 Dennis DA. Wound complications in total knee arthroplasty. University Press, 2006.
Orthopaedics 1997;20;837-40. 43 Judkins DR, Morganstein D, Zador P, Piesse A, Barrett B,
30 Jonsson K, Jensen JA, Goodson WH, Scheuenstuhl H, West J, Mukhopadhyay P. Variable selection and raking in propensity
Hopf HW, et al. Tissue oxygenation, anaemia and perfusion in scoring. Stat Med 2007;26:1022-33.
relation to wound healing in surgical patients. Ann Surg
1991;214,605-13. Accepted: 9 December 2009

page 8 of 8 BMJ | ONLINE FIRST | bmj.com

View publication stats