Brachial plexus injury
Reprint requests to: Dr. Alan R. Hudson, Neurosurgeon in chief, St. Michael's Hospital, 30 Bond St., Toronto, Ont. M5B 1W8
resolution of the anesthesia, though perception was blunted. The opposing surfaces of the thumb and index finger, however, remained totally anesthetized. Electromyographic studies demonstrated activity under voluntary control in the deltoid, brachioradialis and abductor digiti minimi muscles. Sampling of the deep cervical musculature revealed normal electric activity. A cervical myelogram showed no abnormality. Injection of histamine phosphate in the C6 dermatome bilaterally resulted in a normal triple response on the right side but absence of flare on the left side.7 A week later the pectoralis major and minor muscles were reflected and a further fragment of clavicle was resected to allow complete dissection of the trunks and cords of the brachial plexus.8'9 The subclavian vein was dissected from the neural elements with considerable difficulty, and operative injuries to the vein were repaired in the usual way. The operative findings are summarized in Fig. 2. With the Kline portable stimulator/ recorder, evidence of nerve fibre continuity was obtained in all elements of the plexus except the musculocutaneous nerve,10 which was identified as the structure that had been tagged at the first operation. The proximal and distal stumps of this nerve were dissected and both ends were trimmed until a normal fascicular pattern was observed with the operating microscope (Fig. 3). Interfascicular sural nerve autografts were sutured under magnification.
ance of activity in the deltoid muscle (innervated by C5 and C6) countered this concern, and the presence of normal activity in the posterior primary ramus, as demonstrated by normal electromyographic recordings from the deep cervical musculature, added weight to the suspicion that the lesion was primarily extraforaminal . The normal cervical myelogram and the abnormal triple response to injection of histamine phosphate provided further evidence for this view.7'13'14 The clinical and intraoperative stimulation and recording indicated that, apart from the injury to the musculocutaneous nerve, the damage was primarily that of a lesion in continuity, with intact fascicular structure. Operative choices were external neu-
rolysis, internal neurolysis or resection. For most lesions in continuity the damage is intrafascicular, so it is difficult to see how external neurolysis, which inevitably is followed by further scarring, can affect the structure and function of the nerve fibres. This procedure is controversial, opinions ranging from enthusiastic to opposed.8'15 In our case we thought that microsurgical dissection of the trunks and divisions of the nerves was more likely to result in further injury than in gain. Internal neurolysis, which also has no proven scientific merit, and would certainly have caused further damage, was not considered. The knowledge that reconstructive procedures designed to overcome failure of elbow flexion frequently give
Comments The impaired action of muscles innervated by the cervical roots (rhomboid, C5; serratus anterior, C5, 6 and 7) gave rise to concern that the roots either had been directly injured or had been avulsed by the blast. The appear-
.fJ& -' -
.
. . .
4
'S .'
.
3-Damaged musculocutaneous nerve. Nerve fibre undergoing Wallerian degenera(horizontal arrow). Suture fragments (vertical arrows) (osmium tetroxide; x3000).
CMA JOURNAL/NOVEMBER 19, 1977/VOL. 117 1163
I NTERFASCICULAR GRAFT
General Hospital, Toronto, for permission to publish this case report, and Dr. H. Berry, department of neurology, St. Michael's Hospital, Toronto, for performing the electromyographic studies. References t'..
DISTAL STUMP
PROXIMAL STUMP
FIG. 4-Interfascicular graft between stumps of musculocutaneous nerve.
results that are less than perfect prompted extremely close attention to the musculocutaneous nerve. The most important surgical principle in secondary repair is to resect to a point where a normal fascicular pattern is apparent; such a pattern is easily recognized with the operating microscope, provided sufficient time has elapsed since the injury to allow scar and normal fascicle to be disfinguished. Extensive clinical and experimental evidence favours direct suture over grafting in most nerve injuries. The opportunity for axon sprouts to grow into the epineural tissues rather than the endoneurium is doubled in nerve grafting. In our case the longitudinal extent of the injury precluded apposition of the proximal and distal stumps of the musculocutaneous nerve, so sural nerve autografts were interposed between the fascicles. The suture lines were free of tension, a factor thought to be of great importance by some surgeons, although this has not been proven by controlled experimental studies in primates.16-18 Axonal growth into the epineural tissues, a major reason for graft failure, was minimized by careful perineural suture with 10-0 nylon19 (Fig. 4). Accurate sewing with* nonirritating material minimizes bulb formation along the suture line.20 Because endoneural fibroblasts are abundant within the fascicle there is no point in placing a Silastic (polymeric silicone) sheath around the anastomosis in an attempt to keep them out. The marginal potential benefit of using a cuff is outweighed by the possibility of ischemic damage within the swollen fascicles. Daily physiotherapy prevented joint contracture and the appropriate resting splints were applied. Pain was prominent and attempts were made to control it with nonaddicting drugs. The patient underwent psychotherapy. Comment
Pain may be a major factor limiting rehabilitation, so if it had persisted alternative procedures would have been necessary to control it.21
Reassessment 4 months after injury showed further improvement in sensory function and return of modified sensation to the crucial areas of thumb and index finger. The return of motor function is shown in Table I. The patient was lucky that the lower elements of the plexus were not divided by the shotgun blast.22. Further follow-up was conducted by a peripheral nerve injury team whose members included a neurosurgeon, a physiatrist, a psychiatrist, an electromyographer and a reconstructional surgeon.
Comments With remyelination of segmentally demyelinated fibres function continues to recover in the early months after such an injury. The more severely injured fibres in the intact fascicles undergo Wallerian degeneration.3'4 Their regenerating axon sprouts have to grow down the endoneurial tissues, meet the end-organs and subsequently mature before a return of function is noted. It was hoped that most of the axon sprouts derived from the musculocutaneous nerve would be captured by the interfascicular grafts and would grow through the endoneurium, assisted by the Schwann cells of the grafts, and subsequently would enter the fascicles of the distal stump of the nerve. Any decision regarding reconstruction procedures would therefore be postponed for at least 1 year. Examination 18 months after injury revealed good return of muscle power (Table I). Elbow flexion was accomplished primadly by the brachioradialis muscle (radial nerve), with some assistance from the weak biceps and brachialis muscles. Supination was weak and was performed with the aid of trick movements. Sensation was present in the autonomous zones of both median and ulnar nerves and, although of abnormal quality, allowed practical protection and provided sensory information necessary for coordinated motor function. The patient could perform push-ups, pick up a dime from a flat surface, make a fist and lift a full glass of beer to his lips without spilling the contents. He felt that he was still improving. We thank the referring surgeon, Dr. G.K. Wlodek, surgeon in chief, North York
1164 CMA JOURNAL/NOVEMBER 19, 1977/VOL. 117
1. BINNS JH, PARRY CB: Successful repair of a complete brachial plexus lesion. Injury 2: 19, 1970 2. Moiutis J, HUDSON AR, WEDDELL G: A study of degeneration and regeneration in lie divided rat sciatic nerve based on electron microscopy. I. The traumatic degeneration of myelin in the proximal stump of the divided nerve. Z Zelljorsch Mikrosk Anal 124: 76, 1972 3. KLINE D, HUDsON AR, HACKETr ER, et al:
4. 5. 6. 7.
Progression of partial experimental injury to peripheral nerve. Part I: Periodic measurements of muscle contraction strength. I Neurosurg 42: 1, 1975 HUDSON AR, KLINE D: Progression of partial experimental injury to peripheral nerve. Part 2: Light and electron microscopic studies. Ibid, p 15 NULSEN FE, KLINE D: Acute injuries of peripheral nerves, in Neurological Surgery, vol 2, YOUMANS J (ed), Philadelphia, Saunders, 1973, p 1089 SUNDERLAND 5: Rate of regeneration in human peripheral nerves. Arch Neurol Psychiatr 58: 1, 1947 BONNEY G: Value of axon responses in determining the site of the lesion in traction injuries of the brachial plexus. Brain 77: 588, 1954
8. LussKIN R, CAMPBELL JB, THOMPSON WA:
9. 10. 11. 12.
Post-traumatic lesions of the brachial plexus: treatment by transclavicular exploration and neurolysis or autograft reconstruction. I Bone Joint Surg [Am] 55: 1159, 1973 BATEMAN JE: Operative approach to supraclavicular plexus injuries. J Bone Joint Surg [Br] 31: 34, 1949 KLINE DG, DEJONGE BR: Evoked potentials to evaluate peripheral nerve injuries. Surg Gynecol Obstet 127: 1239, 1968 BUPALINI C, PascAToss G: Posterior cervical electromyography in the diagnosis and prognosis of brachial plexus injuries. I Bone Joint Surg [Br] 51: 627, 1969 STANWOOD JE, KRAPT GH: Diagnosis and management of brachial plexus injuries. Arch Phys Med Rehabil 52: 52, 1971
13. MURPHEY
F,
HARTUNO
W,
KINKLIN
JW:
Myelographic demonstration of avulsing injury of the brachial plexus. Am I Roentgenol Radium Ther Nuci Med 58: 102, 1947 14. LEPFERT RD: Brachial plexus injuries. N Engi I Med 291: 1059, 1974 15. KLINE D, HUDSON AR: Surgical repair of acute peripheral nerve injuries, in Controversies in Neurosurgery, chap 8, MORLEY TP (ed), Philadelphia, Saunders, 1976 16. MILLEsI H, MEISSL G, BERGER A: The interfascicular nerve grafting of the median and ulnar nerves. I Bone Joint Surg [Am] 54: 727, 1972 17. MILLESI H, MIESSL G, KATSER H: Zur Be-
handlung der Verletzungen des Plexus brachialis einer Vorschlag einer integrierten Therapie. Bruns Beitr Kim Chir 220: 429, 1973
18. BRATrON B, KLINE D, HUDSON AR: Nerve
repair. Interfascicular suture vs interfascicular graft. Paper presented at the Canadian Congress of Neurological Sciences, London, Ont., 1975
19. HUDSON AR, MORRIS J, WEDDELL G, et al:
Peripheral nerve autografts. J Surg Res 12: 267, 1972 20. HUDSON AR, HUNTER D: Polyglycolic acid suture in peripheral Nerve II: sutured sciatic nerve. Can I Neurol Sci 3: 69, 1976 21. ZORUB DS, NASHOLD BLAINE 5, COOK WA:
Avulsion of the brachial plexus: a review with implications on the therapy of intractable pain. Surg Neurol 2: 347. 1974 22. BROOKS DM: Open wounds of the brachial plexus in peripheral nerve injuries. Med Res Counc Spec Rep Ser (Lond) 282: 418, 1954 23. DRAKE CG: Diagnosis and treatment of lesions of the brachial plexus and adjacent structures. Clin Neurosurg 11: 110, 1963 24. NULSEN FE, SLAVE HW: Recovery following injury to the brachial plexus in peripheral nerve regeneration, in Peripheral Nerve Regeneration, WOODHALL B, BEEBE GW (eds),
VA monograph, Washington, 1957, p 389 25. SARKIN TL: The diagnosis and treatment of brachial plexus lesions. S Air I Surg 13: 107, 1975 26. NELSON KG, JOLLY PC, THOMAS PA: Bra-
chial plexus injuries associated with missile wounds of the chest: a report of nine cases from Viet Nam. I Trauma 8: 268. 1968
Reprint requests to: Dr. Alan R. Hudson, Neurosurgeon in chief, St. Michael's Hospital, 30 Bond St., Toronto, Ont. M5B 1W8
resolution of the anesthesia, though perception was blunted. The opposing surfaces of the thumb and index finger, however, remained totally anesthetized. Electromyographic studies demonstrated activity under voluntary control in the deltoid, brachioradialis and abductor digiti minimi muscles. Sampling of the deep cervical musculature revealed normal electric activity. A cervical myelogram showed no abnormality. Injection of histamine phosphate in the C6 dermatome bilaterally resulted in a normal triple response on the right side but absence of flare on the left side.7 A week later the pectoralis major and minor muscles were reflected and a further fragment of clavicle was resected to allow complete dissection of the trunks and cords of the brachial plexus.8'9 The subclavian vein was dissected from the neural elements with considerable difficulty, and operative injuries to the vein were repaired in the usual way. The operative findings are summarized in Fig. 2. With the Kline portable stimulator/ recorder, evidence of nerve fibre continuity was obtained in all elements of the plexus except the musculocutaneous nerve,10 which was identified as the structure that had been tagged at the first operation. The proximal and distal stumps of this nerve were dissected and both ends were trimmed until a normal fascicular pattern was observed with the operating microscope (Fig. 3). Interfascicular sural nerve autografts were sutured under magnification.
ance of activity in the deltoid muscle (innervated by C5 and C6) countered this concern, and the presence of normal activity in the posterior primary ramus, as demonstrated by normal electromyographic recordings from the deep cervical musculature, added weight to the suspicion that the lesion was primarily extraforaminal . The normal cervical myelogram and the abnormal triple response to injection of histamine phosphate provided further evidence for this view.7'13'14 The clinical and intraoperative stimulation and recording indicated that, apart from the injury to the musculocutaneous nerve, the damage was primarily that of a lesion in continuity, with intact fascicular structure. Operative choices were external neu-
rolysis, internal neurolysis or resection. For most lesions in continuity the damage is intrafascicular, so it is difficult to see how external neurolysis, which inevitably is followed by further scarring, can affect the structure and function of the nerve fibres. This procedure is controversial, opinions ranging from enthusiastic to opposed.8'15 In our case we thought that microsurgical dissection of the trunks and divisions of the nerves was more likely to result in further injury than in gain. Internal neurolysis, which also has no proven scientific merit, and would certainly have caused further damage, was not considered. The knowledge that reconstructive procedures designed to overcome failure of elbow flexion frequently give
Comments The impaired action of muscles innervated by the cervical roots (rhomboid, C5; serratus anterior, C5, 6 and 7) gave rise to concern that the roots either had been directly injured or had been avulsed by the blast. The appear-
.fJ& -' -
.
. . .
4
'S .'
.
3-Damaged musculocutaneous nerve. Nerve fibre undergoing Wallerian degenera(horizontal arrow). Suture fragments (vertical arrows) (osmium tetroxide; x3000).
CMA JOURNAL/NOVEMBER 19, 1977/VOL. 117 1163
I NTERFASCICULAR GRAFT
General Hospital, Toronto, for permission to publish this case report, and Dr. H. Berry, department of neurology, St. Michael's Hospital, Toronto, for performing the electromyographic studies. References t'..
DISTAL STUMP
PROXIMAL STUMP
FIG. 4-Interfascicular graft between stumps of musculocutaneous nerve.
results that are less than perfect prompted extremely close attention to the musculocutaneous nerve. The most important surgical principle in secondary repair is to resect to a point where a normal fascicular pattern is apparent; such a pattern is easily recognized with the operating microscope, provided sufficient time has elapsed since the injury to allow scar and normal fascicle to be disfinguished. Extensive clinical and experimental evidence favours direct suture over grafting in most nerve injuries. The opportunity for axon sprouts to grow into the epineural tissues rather than the endoneurium is doubled in nerve grafting. In our case the longitudinal extent of the injury precluded apposition of the proximal and distal stumps of the musculocutaneous nerve, so sural nerve autografts were interposed between the fascicles. The suture lines were free of tension, a factor thought to be of great importance by some surgeons, although this has not been proven by controlled experimental studies in primates.16-18 Axonal growth into the epineural tissues, a major reason for graft failure, was minimized by careful perineural suture with 10-0 nylon19 (Fig. 4). Accurate sewing with* nonirritating material minimizes bulb formation along the suture line.20 Because endoneural fibroblasts are abundant within the fascicle there is no point in placing a Silastic (polymeric silicone) sheath around the anastomosis in an attempt to keep them out. The marginal potential benefit of using a cuff is outweighed by the possibility of ischemic damage within the swollen fascicles. Daily physiotherapy prevented joint contracture and the appropriate resting splints were applied. Pain was prominent and attempts were made to control it with nonaddicting drugs. The patient underwent psychotherapy. Comment
Pain may be a major factor limiting rehabilitation, so if it had persisted alternative procedures would have been necessary to control it.21
Reassessment 4 months after injury showed further improvement in sensory function and return of modified sensation to the crucial areas of thumb and index finger. The return of motor function is shown in Table I. The patient was lucky that the lower elements of the plexus were not divided by the shotgun blast.22. Further follow-up was conducted by a peripheral nerve injury team whose members included a neurosurgeon, a physiatrist, a psychiatrist, an electromyographer and a reconstructional surgeon.
Comments With remyelination of segmentally demyelinated fibres function continues to recover in the early months after such an injury. The more severely injured fibres in the intact fascicles undergo Wallerian degeneration.3'4 Their regenerating axon sprouts have to grow down the endoneurial tissues, meet the end-organs and subsequently mature before a return of function is noted. It was hoped that most of the axon sprouts derived from the musculocutaneous nerve would be captured by the interfascicular grafts and would grow through the endoneurium, assisted by the Schwann cells of the grafts, and subsequently would enter the fascicles of the distal stump of the nerve. Any decision regarding reconstruction procedures would therefore be postponed for at least 1 year. Examination 18 months after injury revealed good return of muscle power (Table I). Elbow flexion was accomplished primadly by the brachioradialis muscle (radial nerve), with some assistance from the weak biceps and brachialis muscles. Supination was weak and was performed with the aid of trick movements. Sensation was present in the autonomous zones of both median and ulnar nerves and, although of abnormal quality, allowed practical protection and provided sensory information necessary for coordinated motor function. The patient could perform push-ups, pick up a dime from a flat surface, make a fist and lift a full glass of beer to his lips without spilling the contents. He felt that he was still improving. We thank the referring surgeon, Dr. G.K. Wlodek, surgeon in chief, North York
1164 CMA JOURNAL/NOVEMBER 19, 1977/VOL. 117
1. BINNS JH, PARRY CB: Successful repair of a complete brachial plexus lesion. Injury 2: 19, 1970 2. Moiutis J, HUDSON AR, WEDDELL G: A study of degeneration and regeneration in lie divided rat sciatic nerve based on electron microscopy. I. The traumatic degeneration of myelin in the proximal stump of the divided nerve. Z Zelljorsch Mikrosk Anal 124: 76, 1972 3. KLINE D, HUDsON AR, HACKETr ER, et al:
4. 5. 6. 7.
Progression of partial experimental injury to peripheral nerve. Part I: Periodic measurements of muscle contraction strength. I Neurosurg 42: 1, 1975 HUDSON AR, KLINE D: Progression of partial experimental injury to peripheral nerve. Part 2: Light and electron microscopic studies. Ibid, p 15 NULSEN FE, KLINE D: Acute injuries of peripheral nerves, in Neurological Surgery, vol 2, YOUMANS J (ed), Philadelphia, Saunders, 1973, p 1089 SUNDERLAND 5: Rate of regeneration in human peripheral nerves. Arch Neurol Psychiatr 58: 1, 1947 BONNEY G: Value of axon responses in determining the site of the lesion in traction injuries of the brachial plexus. Brain 77: 588, 1954
8. LussKIN R, CAMPBELL JB, THOMPSON WA:
9. 10. 11. 12.
Post-traumatic lesions of the brachial plexus: treatment by transclavicular exploration and neurolysis or autograft reconstruction. I Bone Joint Surg [Am] 55: 1159, 1973 BATEMAN JE: Operative approach to supraclavicular plexus injuries. J Bone Joint Surg [Br] 31: 34, 1949 KLINE DG, DEJONGE BR: Evoked potentials to evaluate peripheral nerve injuries. Surg Gynecol Obstet 127: 1239, 1968 BUPALINI C, PascAToss G: Posterior cervical electromyography in the diagnosis and prognosis of brachial plexus injuries. I Bone Joint Surg [Br] 51: 627, 1969 STANWOOD JE, KRAPT GH: Diagnosis and management of brachial plexus injuries. Arch Phys Med Rehabil 52: 52, 1971
13. MURPHEY
F,
HARTUNO
W,
KINKLIN
JW:
Myelographic demonstration of avulsing injury of the brachial plexus. Am I Roentgenol Radium Ther Nuci Med 58: 102, 1947 14. LEPFERT RD: Brachial plexus injuries. N Engi I Med 291: 1059, 1974 15. KLINE D, HUDSON AR: Surgical repair of acute peripheral nerve injuries, in Controversies in Neurosurgery, chap 8, MORLEY TP (ed), Philadelphia, Saunders, 1976 16. MILLEsI H, MEISSL G, BERGER A: The interfascicular nerve grafting of the median and ulnar nerves. I Bone Joint Surg [Am] 54: 727, 1972 17. MILLESI H, MIESSL G, KATSER H: Zur Be-
handlung der Verletzungen des Plexus brachialis einer Vorschlag einer integrierten Therapie. Bruns Beitr Kim Chir 220: 429, 1973
18. BRATrON B, KLINE D, HUDSON AR: Nerve
repair. Interfascicular suture vs interfascicular graft. Paper presented at the Canadian Congress of Neurological Sciences, London, Ont., 1975
19. HUDSON AR, MORRIS J, WEDDELL G, et al:
Peripheral nerve autografts. J Surg Res 12: 267, 1972 20. HUDSON AR, HUNTER D: Polyglycolic acid suture in peripheral Nerve II: sutured sciatic nerve. Can I Neurol Sci 3: 69, 1976 21. ZORUB DS, NASHOLD BLAINE 5, COOK WA:
Avulsion of the brachial plexus: a review with implications on the therapy of intractable pain. Surg Neurol 2: 347. 1974 22. BROOKS DM: Open wounds of the brachial plexus in peripheral nerve injuries. Med Res Counc Spec Rep Ser (Lond) 282: 418, 1954 23. DRAKE CG: Diagnosis and treatment of lesions of the brachial plexus and adjacent structures. Clin Neurosurg 11: 110, 1963 24. NULSEN FE, SLAVE HW: Recovery following injury to the brachial plexus in peripheral nerve regeneration, in Peripheral Nerve Regeneration, WOODHALL B, BEEBE GW (eds),
VA monograph, Washington, 1957, p 389 25. SARKIN TL: The diagnosis and treatment of brachial plexus lesions. S Air I Surg 13: 107, 1975 26. NELSON KG, JOLLY PC, THOMAS PA: Bra-
chial plexus injuries associated with missile wounds of the chest: a report of nine cases from Viet Nam. I Trauma 8: 268. 1968
