Ipsilateral c7 Nerve Root

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CLINICAL APPLICATION OF IPSILATERAL C7 NERVE ROOTTRANSFER FOR TREATMENT OF C5 AND C6 AVULSIONOF BRACHIAL PLEXUS

Y.-D. GU, M.D.,* P.-Q. CAI, M.D., F. XU, M.D., F. PENG, M.D.,AND L. CHEN, M.D.

We applied a nerve transfer, using the ipsilateral C7 nerveroot to treat the C5 and C6 root avulsion of the brachialplexus. Four patients with C5 and C6 preganglionic injurywere operated on with this new technique from 19982000.Transfer of the spinal accessory nerve to the suprascapularnerve was simultaneously done in 2 these patients. After afollow-up of 12.5 years, the muscle strength of elbow flexorsrecovered to M4 (Lovett) in all cases, shoulder abduction of

>90 with external rotation of 30

40 was gained in twocases, and that of 1545 with no external rotation in theother two cases. No remarkable impairment was2 found in all

C7-innervated muscles except for decrease of muscle powerof 1 grade (Lovett) in the short run. This new technique showspromise as an efficacious and safe treatment for C5 and C6root avulsion of the brachial plexus. However, it should beapplied prudently when incomplete injuries of the lower trunkare involved.

2003 Wiley-Liss, Inc.

MICROSURGERY 23:105108 2003

Neurotization with healthy-side C7 nerve root fortreatment of total root avulsion of the brachial plexus,

as described previously,14 has proven an efficacious

and safe surgery. As to the treatment for C5 and C6 root

avulsion of the brachial plexus, we reported a procedure

of transferring selective fascicles of the anterior division

of the ipsilateral C7 nerve root to the anterior division of

the upper trunk; the functional recovery of elbow flexionhas been satisfactory.5,6 On the basis of our previous

work, we applied a new technique of using transfer of

the ipsilateral C7 nerve root (whole root) for treatment

of C5 and C6 root avulsion, for restoration of shoulder

abduction and elbow flexion. Results were satisfactory.

PATIENTS AND METHODS

All 4 patients were male, and their age varied from

2349 years, with an average of 32 years. The injured

side was on the right in 2 cases.The injury was caused by

traffic accident in 3 cases, and by stabbing in 1 case.Preoperative examination demonstrated a complete loss

of muscle function innervated by the upper trunk of the

brachial plexus at the affected side in all patients.

Phrenic nerve injury was found in all and spinal acces-

sory injury in 2 cases, as shown in Table 1. Electro-

myography (EMG), neurophysiology with compound

muscle action potential (CMAP), and somatosensory

evoked potential (SEP) were performed in all cases and,

based on the combined findings of our clinical exami-

nation, a diagnosis of C5 and C6 preganglionic injurywas made.

The brachial plexus was explored in the usual way,

and dorsal ganglions of C5 and C6 were found in all

cases. The C7 nerve root was dissected free, and its

normality was confirmed by a perioperative neurophys-

iology test. C7 was then blocked with 1% procaine,1 and

divided at the distal level of divisions. The anterior and

posterior divisions of C7 were transferred to those of the

upper trunk, and in 2 cases, the suprascapular nerve was

neurotized with the spinal accessory nerve. The anasto-

mosis was made with microsutures. Postoperative man-

agement included immobilization of the affected limb

with a head-arm brace for 4 weeks, and medication with

nerve nutrient drugs (vitamins B1, B6, and B12). Reha-

bilitation exercises and electric stimulation with a cus-

tom-made instrument were begun after immobilization.

RESULTS

At postoperative 1 week, the power of C7-innervated

muscles decreased by 1 grade (Lovett) in comparison

with preoperation levels. There was numbness in the

Department of Hand Surgery, Hua-Shan Hospital, Fu-Dan University,Shanghai, China

*Correspondence to: Yu-Dong Gu, Department of Hand Surgery, Hua-ShanHospital, Fu-Dan University, 12 Ulumuqi Middle Road, Shanghai, 200040Peoples Republic of China. E-mail: [email protected]

Received 14 January 2002; Accepted 11 February 2003

Published online in Wiley InterScience (www.interscience.wiley.com).DOI:10.1002/micr.10113

2003 Wiley-Liss, Inc.


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thumb web in all cases (Table 2). A neurophysiology testshowed that the amplitude and latency of CMAP was not

significantly different from those from preoperation.7 At

postoperative 6 months, however, muscles innervated by

the C7 nerve root had recovered to normal in all cases,

and the numbness in the thumb web disappeared in 2

cases, but was still present in the other 2 cases.

Over the first period of 36 months after the oper-

ation, muscle contraction of the biceps and deltoid was

found in all cases; in 1 case with the suprascapular nerve

neurotized by the spinal accessory nerve, the suprasp-

inous and infraspinous muscles could feel contracted. At

1230 months postoperatively, the biceps improved to

M4 in all cases; a shoulder abduction of >90 and ex-

ternal rotation (in adduction) of30 were gained in 2

cases with the spinal accessory nerve transfer, while in

the other 2 cases with no extra spinal accessory nerve

transfer, abduction of shoulder was only 30 on average,

with hardly any external rotation (Table 3).

TYPICAL CASE

A man (case 4 in Table 1) who was injured in a

motorcycle accident had a functional loss of the left

shoulder and elbow and was referred to our clinic 50days after injury. Physical examination showed an ab-

sence of pricking pain at the innervation region of C5

and C6 (thumb and index finger), atrophy of the tra-

pezius with M2 muscle power, atrophy of the biceps,

deltoid, supraspinous, infraspinous, and brachiaoradi-

alis with M0, and square shoulder deformity. The

strength of the lattismus dorsi and triceps was M3, that

of the sternal part of the pectoralis major and extensor

digitorium communis was M4, and that of the intrinsic

muscles and finger flexor muscles was normal. Com-

bined with electromyography and neurophysiology tests

(SEP and CMAP), a diagnosis of C5 and C6 root

avulsion of the brachial plexus was made. The plexus

was explored, and the ganglions of C5 and C6 were

found. A perioperative neurophysiology test showed

unresponsiveness of the phrenic nerve, but a normality

of C7, C8, T1, and the spinal accessory nerve. The

middle trunk was then isolated, blocked with 1% pro-

caine, and transected as far as possible. Transfer of the

middle trunk to the proximal part of the anterior and

posterior divisions of the upper trunk, and of the ac-

cessory nerve to the suprascapular nerve, was carried

out with microsutures. After the operation, the affected

Table 1. Clinical Data and Surgical Procedures*

Name Age Sex Affected side Cause Diagnosis Operative delay Surgical procedure Follow-up

Yue6 23 Male Left Traffic accident a, P, A 2.5 months C7 nerve root fi upper trunk 22 months

Zeng 49 Male Right Stabbing b, P, A 2 months C7 nerve root fi upper trunk 30 months

Liu 35 Male Right Traffic accident a, P 5 months C7 nerve root fi upper trunk

Acfi

Sc

24 months

Sun 23 Male Left Traffic accident a, P 50 days C7 nerve root fi upper trunk

Ac fi Ss

12 months

*a, C5 and C6 preganglionic injury; b, C5 and7 C6 postganglionic injury; P, phrenic nerve injury; A, accessory nerve injury; Ac fi Ss, accessory nervefisuprascapular nerve.

Table 2. Comparison of Muscle Strength of C7 Innervated Muscles Between Preoperative and Postoperative Condition*

Lattismus dorsi Triceps brachii Extensor digitorum communis

Case Preop 1w post 0.5y post Preop 1w post 0.5y post Preop 1w post 0.5y post

1 M4 M3 M4 M4 M3 M4 M4 M4 M52 M4 M3 M3 M4 M3 M4 M5 M4 M53 M3 M3 M4 M3 M3 M4 M3+ M3 M4

4 M3+ M3 M4 M3 M4 M5 M4 M4 M5

*Preop, preoperative; 1w post, 1 week after operation; 0.5y post, half a year after operation.

Table 3. Follow-Up Results of Shoulder Abduction, External Rotation, and Elbow Flexion

Case

Follow-up

(months) Deltoid

Supra and

infraspinous

Shoulder

abduction

External

rotation Biceps

1 22 M2 M2 45 10 M42 30 M2 M1 15 0 M43 24 M3 M3 >90 40 M44 12 M4 M3 >90 30 M4

106 Gu et al.


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extremity was immobilized with a head-arm brace. On

the second day after the operation, a grade 1 decrease of

muscle power in the latissmus dorsi and triceps was

found, but the strength of the extensor digitorum com-

munis was normal. The area of loss of pricking pain was

similar to that from preoperation, except for a reduction

of pricking pain in the thumb web. At 1 week after the

operation, an EMG study revealed no spontaneous

electrical activity in the latissmus dorsi, triceps, and

extensor digitorum communis. But the recruitment re-

sponse was feeble, varying from single pattern to single-

mixed pattern. At postoperative 8 months, the patient

showed a shoulder abduction of 70 and external rota-

tion of 10. The strength of the deltoid, supraspinous,

and infraspinous muscles was M2, that of the elbow

flexors was M3, and that of the triceps and extensor

digitorum communis was M5. One year after the oper-

ation, shoulder abduction recovered to 170 and exter-

nal rotation to 30, and the strength of the elbow flexorsto M4. The recovery of daily activity was satisfactory

(Figs. 14).

DISCUSSION

Clinical Significance of Transfer of Ipsilateral

C7 Root

The injury of the upper trunk alone of the brachial

plexus is a common lesion in clinical practice, and ac-

Figure 1. Shoulder abuduction 170, deltoid M4, supraspinous and

infraspinous muscle M3, innervated5 by transferred C7 at postoper-

ative 1 year. [Color figure can be viewed in the online issue, which is

available at www.interscience.wiley.com]

Figure 2. Elbow flexion 150, biceps M4, innervated by transferred

C7, at postoperative 1 year. [Color figure can be viewed in the online

issue, which is available at www.interscience.wiley.com]

Figure 3. Lattismus dorsi M3 (originally innervated by C7), inner-

vated by C8T1 at postoperative 1 year. Arrow indicates the con-

traction of the lattismus dorsi. [Color figure can be viewed in the

online issue, which is available at www.interscience.wiley.com]

Figure 4. Extensor muscles of elbow, wrist, and fingers M4 (origi-

nally innervated by C7), innervated by C8T1 at postoperative 1 year.

[Color figure can be viewed in the online issue, which is available at

www.interscience.wiley.com]

Ipsilateral C7 Nerve Root Transfer 107


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counts for one third of all brachial plexus injuries. Its

main symptoms are impairment of shoulder abduction,

external rotation, and elbow flexion. Since no functional

disturbance occurred in patients with isolated C7 le-

sions,1 the major clinical presentation of injury of C57

was similar to that of C5 and C6. For treatment of C5

and C6 nerve root avulsion, our option of donor nerves

for transfer included the phrenic nerve, accessory nerve,

intercostal nerves, and partial fascicles of the ulnar nerve

(Oberlins procedure). C5 and C6 nerve root avulsion is

sometimes accompanied with injury of the phrenic nerve

and accessory nerve, leading to even more insufficiency

of the donor nerves. We therefore used the ipsilateral C7

nerve root as donor nerve for repair of the upper trunk

of the brachial plexus. Not only was the treatment

outcome enhanced, but a satisfactory neurotizer for in-

juries of the upper trunk or even lower trunk of the

brachial plexus was provided. The procedure caused no

electromyography, neurophysiology, or functional dis-turbance except for a temporary drop of muscle strength

in C7 innervated muscles.7,8 Therefore, it is safe and

efficacious.

Analysis of Treatment Outcome of Transfer

of Ipsilateral C7 Root

The first 2 cases suffered from C5 and C6 nerve root

avulsion, as well as injuries of the phrenic nerve and

accessory nerve. After transfer of the ipsilateral C7

nerve root to the upper trunk, follow-up results showed

muscle strength of the elbow flexors improving to M4,but recovery of shoulder abduction and external rota-

tion was limited. Transfer of the ipsilateral C7 nerve

root to the anterior and posterior division, and of the

accessory nerve to the suprascapular nerve, was per-

formed in the latter 2 cases on account of the normal

accessory nerve function. One year after the operation,

striking treatment efficacy was achieved, with notable

restoration of shoulder abduction and external rotation

in these 2 cases. The difference in recovering shoulder

abduction between the former and the latter 2 cases may

suggest the severity of injury in the former 2, to whom

the accessory and phrenic nerves were simultaneously

injured, which might ultimately influence the regenera-

tion potential and quality of spinal cord neurons, thus

weakening C7 nerve root regeneration. It also confirms

that the function of the suprascapular nerve is of para-

mount importance in maintaining shoulder function,

and therefore it must be neurotized in treatment of C5

and C6 nerve root avulsion of the plexus.

We conclude from this study as follows: 1) Transfer

of the ipsilateral C7 nerve root is the treatment of choice

for C5 and C6 nerve root avulsion of the brachial plexus

in combination with phrenic nerve injury. 2) The pro-

cedure can also be performed with normal phrenic

nerves with insufficiency of cardiorespiratory function.

3) In cases of C5 and C6 nerve root avulsion of the

brachial plexus combined with incomplete middle and

lower trunk injuries, the procedure should be used

cautiously.

REFERENCES

1. Gu Y-D, Zhang G-M, Chen D-S, Yan J-G, Cheng X-M, Chen L.Seventh cervical nerve root transfer from the contralateral healthyside for treatment of brachial plexus root avulsion. J Hand Surg[Br] 1992;17:518521.

2. Gu Y-D, Chen D-S, Zhang G-M, Cheng X-U, Xu J-G, ZhangL-Y, Cai P-Q, Chen L. Long-term functional results of contra-lateral C7 transfer. J Reconstr3 Microsurg 1998;14:5759.

3. Liu J, Pho RWH, Kow AK. Neurologic deficit and recovery in

brachial plexus injury. J Reconstr Microsurg 1997;13:237

242.4. Teizis JK, Skoulis T, Jiginni V. Contralateral C7: a powerfulsource of motor neurons. In: Abstract Book of the 14th4 Congressof the International Microsurgery Society. Corfu, Greece. 1998.

5. Gu Y-D. Symposium on brachial plexus injury: progress in con-tralateral C7 transfer for management of brachial plexus injuries.Hong Kong J Orthop Surg 1999;3:9698.

6. Xu J-G, Hu S-N, Wang H, Shen L-Y, Gu Y-D. A study of theclinical application of ipsilateral selective C7 transfer. Chin J HandSurg 1999;15:3:151153.

7. Xu F, Cai P-Q, Gu Y-D, Chen D-S. Influence of ipsilateral nerveroot transfer on its innervating muscles: a preliminary report.J Chin Hand Surg 2001;17:3:133135.

8. Gu Y-D, Shen L-Y. Electrophysiological changes after severanceof the C7 nerve root. J Hand Surg [Br] 1994;19:6971.

108 Gu et al.

Ipsilateral c7 Nerve Root

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