MYELOPATHY HAND

NEW CLINICAL SIGNS OF CERVICAL CORD DAMAGE

KEIRO ONO, SOHEI EBARA, TAKESHI FUJI, KAZUO YONENOBU, KEIJU FUJIWARA,
KAZUO YAMASHITA

From Osaka University Medical School

A characteristic dysfunction ofthe hand has been observed in various cervical spinal disorders when there
is involvement of the spinal cord. There is loss of power of adduction and extension of the ulnar two or three
fingers and an inability to grip and release rapidly with these fingers. These changes have been termed
“myelopathy hand” and appear to be due to pyramidal tract involvement. The characteristic nature of the
signs permit the distinction between myelopathy and changes due to nerve root or peripheral nerve disorder.
The clinical significance of these signs has been assessed against other tests and their value in management is
discussed.

Clumsiness of the hand is one of the most common fingers. As the disease became more severe this loss of
complaints in patients with spinal cord disorders such as adduction in the ulnar fingers was followed by the
myelopathy secondary to cervical spondylosis. Impaired inability to extend them.
grip may be seen as well as slow, unskilled hand and We have surveyed the prevalence of this “myelo-
finger movements. Yet few reports have been published pathy hand” in various disorders of the cervical spine
on the characteristic dysfunctions of the hand or fingers and cord in an attempt to discover the responsible lesion
in cervical spinal cord disease (Brain and Wilkinson and to assess its diagnostic significance.
1967; Baily 1974). This may be due to the difficulty of
distinguishing between dysfunction caused by cord
PATIENTS AND METHODS
damage and that caused by radicular involvement.
In a prospective study of cervical spondylotic A total of 1 27 patients with cervical spine or cord
myelopathy, we commonly observed a characteristic disorders were examined in this survey. Of these, 79 had
abnormality in the affected hand of patients with evidence of myelopathy and 48 had radiculopathy.
advanced disease (Ono et al. 1977, 1982). There was Details of the patients are given in Table I.
inability to extend the ulnar two or three fingers, despite The diagnosis of “myelopathy hand”. The diagnosis was
relatively well preserved function ofthe wrist, thumb and made by performaning two simple tests:
index finger. Rapid extension of the fingers was 1 The finger
. escape sign - deficient adduction and/or
impossible even in patients with less advanced disease. extension of the ulnar two or threefingers. The patient is
These abnormalities were generally accompanied by an asked to present the arms with fingers forward and palms
exaggerated triceps reflex, positive Wartenberg’s and down. In this position the little finger tends to lie in slight
Hoffmann’s reflexes and long tract signs, such as a abduction and cannot be held in adduction for more than
spastic gait and hyper-reflexia in the lower limbs. We 30 seconds, whereas it can be abducted or be opposed to
found that the earliest change was inability to adduct the the thumb. In more advanced cases, a similar tendency is
little finger; this progressed to affect the ring and middle seen in the ring finger and at rest the two spaces between
the ulnar three fingers are both clearly increased. In
addition, at this stage, full extension at the
K. Ono, MD, Professor and Chairman
interphalangeal joints of the ulnar fingers is lost. As
S. Ebara, MD disability advances the ulnar three fingers become
T. Fuji, MD
K. Yonenobu, MD
significantly flexed at the metacarpophalangeal joint so
K. Fujiwara, MD that the patient can manipulate objects freely only with
K. Yamashita, MD
Department of Orthopaedic Surgery, Osaka University Medical
the thumb and the index finger.
School, 1-1-50 Fukushia, Fukushima-ku, Osaka 553, Japan. In each patient it is important to determine whether
Requests for reprints should be sent to Professor K. Ono. active flexion and extension of the wrist is possible so as
© 1987 British Editorial Society of Bone and Joint Surgery to exclude cases of motor neuron disease or of peripheral
0301 -620X/87/2068 $2.00
nerve involvement. On the results of these tests, we were

VOL. 69-B, NO. 2, MARCH 1987 215

 216 K. ONO. S. EBARA, T. FUJI, K. YONENOBU, K. FUJIWARA, K. YAMASHITA

Table I. Diagnosis, aetiology and incidence of myelopathy hand in I 27

patients

Incidence of
Number myelopathy hand
Diagnosis and aetiology of patients (per cent)

Myelopathy
Cervical spondylosis 31 90.3
%_77_j Cervical disc protrusion 14
( I ‘ ,iL1L Ossification of the posterior 27 92.6
longitudinal ligament (OPLL)
Cord tumour 4 1000
Miscellaneous, e.g. atlanto-axial 3 670
dislocation in rheumatoid arthritis

Radiculopathy (secondary to spondylosis 48 0

in most cases)

* The finger-escape sign alone was present in 15%

able to classify finger disability into five grades, as

described in Table II and illustrated in Figures 1 and 2.
2. Inability’ to grip and release rapidly’ with thefingers. The
patient is asked to grip and release with the fingers as
rapidly as possible, with the arm in the same position as
for the first test (Fig. 3). The number of complete cycles
of movement within 10 seconds is counted. Difficult,
slow and incomplete finger extension was remarkable in
advanced cases; exaggerated wrist flexion with attempt-
ed finger extension and exaggerated wrist extension with
finger flexion were often seen. This was considered to be
caused by a failure of synergy between the wrist and the
fingers. Normal adults can perform such rapid grip and
release movements more than 20 times in 10 seconds. Fig. 2
The lesion responsible for myelopathy hand. The incidence
The finger-escape sign : lack of adduction and extension of the ulnar
of “myelopathy hand” was studied in several groups. fingers (see text and Table II). Figure 1 - Grade 2: Figure 2 - Grade 4.
Patients with spastic lower limbs were compared with
those without such spasticity. Most of the latter group
suffered from radiculopathy secondary to cervical disc
disease or spondylosis. Patients were also examined to
determine correlation of myelopathy hand with spasti-
city of the hand and with lesions at various segmental
levels in the cervical cord. An attempt was made to
correlate the severity of myelopathy hand with efficiency
in the activities of daily living and with walking ability, Fig. 3
in order to determine whether it was related to any
The grip-and-release test. The number of repeated actions within 10
disorder of the long tracts of the spinal cord. seconds is recorded. The normal result is 20 or more.

Table II. Grading of the finger-escape sign

Pathology and neuroradiology. A few patients with

Grade Fingers Deficiency advanced myelopathy hand secondary to cervical spon-
dylosis have come to autopsy (Ono et al. 1977). Marked
0 All None
demyelination, particularly in the lateral and the
I Little Unable to hold adduction posterior columns, and infarction of the grey matter were
2 Little or little and ring Unable to assume adduction
seen in cases with severe compression of the cervical
cord, as assessed by the anteroposterior/width ratio.
3 Little and ring Unable to assume adduction or full
extension
Involvement of the pyramidal tract was commonly seen
and was dependent upon the severity of compression.
4 Little, ring and middle Unable to assume adduction or full
extension
The shape and the size of the cervical cord were
investigated by CT myelography at the affected level.

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 MYELOPATHY HAND 217

Table III. Relation between spastic paresis and myelopathy hand in Table IV. Relation between the segmental level of cervical cord
I 27 patients damage and the incidence ofa positive finger-escape sign in 34 patients
with single level compression

Myelopathy hand diagnosed

Level Number of patients Percentage with positive sign

Per cent of
Test for spasticity Result Number Number group Cl/2 5 80

C3/4 10 80
Spastic gait and Positive 77 67 87.0
exaggerated patellar
C4/5 7 43
tendon reflex
Negative 50 2 4.0 C5/6 9 100

Pathological hand Positive 71 63 88.7 C6/7 3 0

reflex

Negative 56* 6 10.7

based on the assessment of motor, sensory and sphincter
. Included 48 cases of cervical radiculopathy function (Table V) and a normal patient scores a total of
17 points. Good correlation of the total score with the
grade of myelopathy hand, as assessed by the finger-
Recently available high resolution CT gave an exact escape sign, is shown in Figure 4, and there was also good
image of the cervical cord, so that its cross-sectional area correlation with the score for motor dysfunction of the
at the level ofmaximum compression could be measured. lower limbs. Similar correlations were shown for the grip
and release test (Fig. 5).
These results showed that the grade of myelopathy
RESULTS
hand reflected performance, and that the correlation
The incidence of myelopathy hand. Table I shows the with lower limb dysfunction meant that myelopathy
incidence in each of the diagnostic groups of patients hand could be used as an indication of the function of the
who had difficulty with little-finger adduction (Grade 1 cervical spinal cord. Furthermore, a positive finger-
finger-escape sign), and could achieve less than 20 escape sign and inability to repeat rapid grip and release
repetitions of grip and release of the hand within 10 can be inferred to indicate involvement of the pyramidal
seconds with abnormal synergy at the wrist. Irrespective tracts.
ofthe diagnosis, those patients with long tract signs, such Neuroradiology and pathology. In a number of patients
as spastic gait or exaggerated tendon reflexes in the legs, with prolapsed discs or severe spondylosis, the degree of
showed a high prevalence of myelopathy hand as cord compression, as shown by CT myelography,
compared with those without spasticity, who were correlated well with the existence and grade of myelo-
usually complaining of neck, shoulder or arm pain. Most pathy hand. This correlation with the remaining cross-
patients with cervical spondylosis showed no manifesta- Table V. An assessment scale for disability due to cervical myelopathy
tion of myelopathy hand no matter how severe their
(Japanese Orthopaedic Association)
radicular pain, but a Grade 1 finger-escape sign was
occasionally encountered in patients with arm pain and I. Motor dysfunction of the upper extremity
Unable to feed oneself 0
muscle weakness secondary to cervical radiculopathy. Unable to handle chopsticks, able to eat with a spoon
These patients did not, however, have slowness of grip Able to handle chopsticks with much difficulty
Able to handle chopsticks with slight difficulty 3
and release. None 4
The responsible lesion. There was a positive correlation
II. Motor dysfunction of the lower extremity
between the signs of myelopathy hand and spasticity Unable to walk 0
defined by the presence of exaggerated Wartenberg’s Can walk on flat floor with walking aid
Can walk up and/or down stairs with handrail
finger reflex and Hoffman’s reflex (Table III). No Lack of stability and smooth gait 3
correlation was found between myelopathy hand and None 4

cervical cord involvement at any particular level (Table III. Sensory deficit
IV). Patients suffering from high cord compression due Upper extremity
Severe sensory loss or pain 0
to an atlanto-axial lesion presented myelopathy hand as Mild sensory loss
frequently as those patients with a lesion lower in the None 0-2
Lower extremity
cervical spine. However, positive signs of myelopathy Trunk 0-2
hand were rarely seen in paretic patients with cord
IV. Sphincter dysfunction
involvement at C6/7 or below. Unable to void 0
Correlation between myelopathy hand and performance in Marked difficulty in micturition (retention)
Difficulty in micturition (frequency, hesitation)
patients with spastic paresis. The activities of daily living None 3
were scored according to the grading scale proposed by
the Japanese Orthopaedic Association. This scale is * A normal patient scores 1 7 points

VOL. 69-B. NO. 2, MARCH 1987

218 K. ONO, S. EBARA, T. FUJI, K. YONENOBU, K. FUJIWARA, K. YAMASHITA

17 Normal ADL 17 Normal ADL

a)
0
C)
U)
15

10
i * P<0.01 a)

10
15

5 5
I

N=lO N=16 N=26 N=13 N=14

0 0 N=7 N=23 N=27 N=15 N=7
i i o-’4 5-9 1O’-14 15-19 20-24
severe Grip-Release (/10 sec)
Grade of FES

Fig. 4 Fig. 5

To show the relation between myelopathy hand and the activities of daily living (ADL)
according to the score on the scale of the Japanese Orthopaedic Association (Table V).
Figure 4 - Finger-escape sign (FES). Figure 5 - Grip-and-release test.

sectional area is shown in Figure 6. Grade 4 myelopathy

hand, the severest form, was usually seen in patients with 70
compression such that the anteroposterior depth of the
cord was less than one-third of the lateral width. 60
Pathological investigation became possible in a few
cases with severe grades of myelopathy hand and showed
marked diffuse demyelination of the lateral column of
white matter including the pyramidal tract (Figs 7 to 9).
40
The lesion which corresponded to myelopathy hand C
C
appeared to be degeneration of the corticospinal tract, in
a)
since the anterior horn of grey matter at C7, C8 and Ti
levels was generally well preserved.
Sensory changes. A distinct type and distribution of 20

sensory deficiency, with marked insensitivity to pin-

prick, was found in patients with myelopathy hand.
Hypalgesia and even analgesia often extended to the
wrist and the dorsum of the forearm and was not of
N=12N=8 N=12 N=6 N=2
0
dermatome distribution. Lack of pain sensation seemed a i 4
severe
to depend on the severity of myelopathy or compression Grade of FES
of the spinal cord, irrespective of the segmental level
Fig. 6
involved. Insensitivity to pain was greater in the more
peripheral areas and loss of pain sensation was also The relation between the cross-sectional
area of the cervical spinal cord at the level
found on the lateral aspects of the lower legs and feet. of maximum compression on CT myelo-
This pattern of sensory deficit was seen in 75% of the graphy and the grade offinger-escape sign.

patients with myelopathy hand.

DISCUSSION the hands is common in such patients. Myelopathy hand,

Limb spasticity is one of the most common neurological as defined, is a sensitive and specific sign of pyramidal
findings in various disorders of the cervical spine and tract involvement and hence provides an objective test.
cord, confirming the frequent involvement of the The clinical significance of myelopathy hand is
pyramidal tract. But studies of the clinical manifesta- considerable:
tions of pyramidal tract involvement in the hand are 1. Cervical cord involvement can be identified by its
surprisingly rare, in spite of the fact that clumsiness of presence.

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 MYELOPATHY HAND 219

tract. The deeper the damage, the less likely is it to be

reversible, but further study is needed to verify this
statement.
6. The signs of myelopathy hand may be useful to
discriminate between compression myelopathy and
psychosomatic disorders or systemic cord degeneration
but, again, more experience is necessary to verify this.
Differential diagnosis. Grades 1 and 2 of myelopathy
hand resemble the digiti quinti sign in hemiparesis
reported by Alter (1973). This means that the cranial
nerves should be examined carefully for evidence of
abnormality ifsuch a disorder is suspected. However, the
characteristic deficits of pain sensation in the hands and
legs are a distinctive feature in patients suffering from
compression myelopathy unrelated to brain damage.
Ulnar nerve palsy can be excluded by testing the power
of abduction of the little finger and of opposition to the
thumb. In patients with Grade 1 or 2 myelopathy hand,
abduction and opposition of the little finger are usually
possible. In Grade 3 or 4 myelopathy hand, the little
and/or ring finger can be actively flexed at the
metacarpophalangeal joints, which is not possible in
ulnar palsy.
Insufficiency of finger adduction and/or extension
starts and is greatest in the ulnar fingers. This could be
explained by assuming that it is related to the cortical
representation of each finger, which is greater for the
thumb and index than for the little or ring fingers
(Penfield and Rasmussen 1950). If this inequality
continues distally, affecting the number of motor
neurons in the pyramidal tract at cervical level, then the
well innervated thumb and index finger are likely to
show much less motor deficiency as a result of pyramidal
tract involvement than the less well innervated little and
ring fingers. The volar interosseous muscle between the
fourth and fifth metacarpals is known to be poorly
Fig. 9
innervated and therefore susceptible to insufficiency.
Cross-sections of the spinal cord from a patient with severe myelopathy
hand, to show flattening of the cord and degeneration of the lateral This is a possible explanation for the escape of the index
corticospinal tract. From above down, the levels are C4, C6 and Tl. finger and the early appearance of the digiti quinti sign
in cases of pyramidal tract involvement.
2. In cases of cervical spondylosis, where radicular
complaints may coexist with myelopathy, the presence of
signs of myelopathy hand indicates significant cord
compression. REFERENCES
3. Myelopathy hand is useful in patients with various
diseases at the craniocervical junction, in which there Alter M. The digiti quinti sign of mild hemiparesis. Neurology
(Minneap) 1973 ;23 :503-5.
may be few objective symptoms or signs of cord
Baily RW. Applied neuroanatomy and neurological diagnosis. In:
involvement except for spasticity. In fact it indicates a
Baily RW, ed. The cervical spine. Philadelphia : Lea Febiger,
disorder of the upper rather than the lower cervical 1974:98-110.
spine. Brain Lord, Wilkinson M. Cervicalspondylosis and other disorders of the
cervical spine. London: Heinemann, 1967: 124.
4. In patients with marked spastic paraplegia and no
Ono K, Ota H, Tada K, Yamamoto T. Cervical myelopathy secondary to
signs of myelopathy hand, the responsible lesion is likely
multiple spondylotic protrusions : a clinicopathologic study. Spine
to be at or below the cervicodorsal junction. 1977:2:109-25.
5. The grade of myelopathy hand may help indicate the Ono K, Okada K, Fuji 1, Ojlma S. Finger escape sign (FES): an
objective sign signifying pyramidal tract involvement of the
viability ofthe spinal cord and predict the reversibility of
cervical spinal cord. Orthop Trans l982;6(2):18l.
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