- Email: [email protected]
Patient outcome after surgical management of an accessory nerve injury
Patient outcome after surgical management of an accessory nerve injury CHRISTINE B. NOVAK,
PT, MS,
and SUSAN E. MACKINNON,
MD,
OBJECTIVE: This study assessed patient outcome following surgical reconstruction of the accessory nerve after an iatrogenic injury. STUDY DESIGN: A retrospective chart review of 8 patients was performed. RESULTS: There were 3 men and 5 women in the study, and the mean time between injury and nerve graft/repair surgery was 5 months. Four injuries were sustained during a lymph node biopsy. Electromyography revealed a complete accessory nerve injury in all cases. In 6 cases, a nerve graft was required (mean length, 3.6 cm), and in 2 cases, a direct nerve repair was possible. The trapezius muscle was successfully reinnervated in all cases. In total, full shoulder abduction was achieved in 6 cases; in the remaining 2 cases, the patients achieved shoulder abduction to 90°. CONCLUSION: Functional deficit after accessory nerve injury is significant. Nerve graft/repair reconstruction reliably yields a satisfactory result, providing good scapular rotation and thus good shoulder function. (Otolaryngol Head Neck Surg 2002;127: 221-24.)
T he accessory nerve provides motor innervation to the trapezius and sternocleidomastoid muscles.1 Injury to the accessory nerve that results in denervation of the trapezius muscle will result in a lack of scapular rotation, particularly with shoulder abduction, producing a profound functional shoulder deficit.2 Surgical exploration in the posterior triangle region of the neck places the accessory nerve at risk for iatrogenic injury3,4 (Fig 1). Early recognition and surgical reconstruction of this inFrom the Division of Plastic and Reconstructive Surgery, Washington University School of Medicine. Presented at the Annual Meeting of the American Association for Hand Surgery, Cancun, Mexico, January 10, 2002. Reprint requests: Susan E. Mackinnon, MD, Division of Plastic and Reconstructive Surgery, Suite 17424, East Pavilion, One Barnes-Jewish Hospital Plaza, St Louis, MO 63110; e-mail, [email protected]. Copyright © 2002 by the American Academy of Otolaryngology–Head and Neck Surgery Foundation, Inc. 0194-5998/2002/$35.00 ⫹ 0 23/78/126805 doi:10.1067/mhn.2002.126805
St Louis, Missouri
Fig 1. Anatomic drawing of the posterior triangle. The accessory nerve traverses within the posterior triangle between the sternocleidomastoid and trapezius muscle. At the border of the sternocleidomastoid muscle, the accessory is located above the greater auricular nerve. (Reproduced with permission from Thomas H. Tung, MD.)
jury are imperative for reinnervation of the trapezius muscle to avoid unnecessary loss of shoulder function.5-12 This study assessed patient outcome after surgery to correct an iatrogenic injury to the accessory nerve. METHODS After approval by the institutional Human Studies Committee, 8 patient charts were reviewed. Inclusion criteria included referral to a single surgeon and an accessory nerve repair or graft that was performed after an iatrogenic injury to the accessory nerve. RESULTS There was a total of 3 men and 5 women with a mean age of 50 years (SD, 10 years; age range, 39 221
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Otolaryngology– Head and Neck Surgery September 2002
Fig 2. A, Patient underwent a lymph node biopsy through an incision in the region of the posterior triangle and sustained an accessory nerve injury. B, After an accessory nerve graft, the patient achieved full shoulder abduction with only minimal inferior angle winging.
to 65 years). All patients had sustained an iatrogenic accessory nerve injury; 4 injuries were sustained during a lymph node biopsy, 1 during a melanoma excision, 1 during cyst excision, 1 during lipoma excision, and 1 during a reexcision of a desmoid tumor. Electrodiagnostic studies in 8 cases revealed a complete accessory nerve injury with fibrillations to the trapezius muscle and no evidence of spontaneous recovery. The mean time between injury and nerve graft/ repair surgery was 5 months (SD, 2.6 months; range, 2 to 9 months). In 6 cases, a nerve graft was needed to restore neural continuity (mean length, 3.4 cm; range, 2 to 4.5 cm), and in 2 cases, a direct nerve repair was possible. In all cases of nerve grafting, the anterior branch of the medial antebrachial cutaneous nerve (MABC) was used as the donor nerve graft. The trapezius muscle was successfully reinnervated in all 8 cases. In 6 patients, full shoulder abduction was achieved and patients reported no functional limitations of the shoulder (Fig 2). Two patients achieved improved shoulder abduction to 90° with less scapular winging than noted preoperatively. DISCUSSION Injury to the accessory nerve causing denervation of the trapezius muscle results in significant restriction of shoulder motion, particularly shoulder abduction.2 Upper trapezius muscle function loss will result in a loss of shoulder shrug, and a loss of the middle trapezius muscle function will
result in a loss of medial scapular adduction. Loss of the lower trapezius muscle will result in a loss of scapular rotation, particularly with glenohumeral abduction. Over time the lack of trapezius muscle function will result in a “droopy” shoulder because of scapular depression and downward rotation. Prolonged positioning of the shoulder girdle in this depressed position may produce patient complaints of pain, paraesthesia, and/or numbness in the upper extremity. Patient examination after an injury to the accessory nerve must include evaluation of the shoulder range of motion with attention to the associated scapular motions.2 Patients may exhibit relatively good shoulder elevation via the innervation of the upper trapezius muscle through the cervical plexus branches.4 This innervation of the upper trapezius muscle often leads to the erroneous assumption that the accessory nerve is intact or at least partially intact.4,6 Evaluation of shoulder range of motion, particularly shoulder abduction and forward flexion, will yield valuable information regarding the innervation of the trapezius muscle and the integrity of the accessory nerve. With an injury to the main branch of the accessory nerve, active shoulder abduction will be severely restricted and scapular winging will be noted. Patients may present with good shoulder flexion because of the normal functioning serratus anterior muscle, although in some patients forward flexion may also be decreased but to a lesser degree than shoulder abduction.
Otolaryngology– Head and Neck Surgery Volume 127 Number 3
The etiology of the injury is significant in considering the options for treatment. In cases where surgical exploration in the region of the posterior triangle of the neck has resulted in a lack of trapezius muscle function, an accessory nerve laceration should be suspected until proved otherwise. In surgical cases where the accessory nerve injury is recognized at the time, a primary nerve repair should be performed, and if a tension-free repair is not possible, then a nerve graft is indicated. In cases where the patient presents with ongoing pain and loss of shoulder function after a surgical procedure in the posterior triangle neck region, a thorough clinical evaluation and electrodiagnostic studies are necessary to ascertain whether a nerve injury has occurred and to identify whether there is evidence of recovery. Electrodiagnostic studies should be conducted 4 to 6 weeks after the nerve injury because muscle denervation changes will be evident at this time. Repeat electrodiagnostic studies at 3 months should show evidence of reinnervation in the upper and middle trapezius muscle or surgical exploration should be considered. Many needle electromyographic studies examine only the upper trapezius muscle and a false-negative result may occur if the upper trapezius is innervated by the cervical branches of the accessory nerve. For a complete electromyographic study, the upper, middle, and lower trapezius muscles should be examined. In cases of severe atrophy of the middle and lower trapezius muscles, the electromyographer must take care to place the needle in only the trapezius muscle and not the underlying innervated muscles. For example, normal studies of the upper trapezius with denervation changes and no signs of reinnervation in the middle and lower trapezius muscle at 3 months do not imply recovery. It suggests innervation of the upper trapezius muscle by the cervical plexus and a complete injury to the main accessory nerve. By contrast, changes in fibrillations and motor unit potentials in the upper trapezius muscle with the same denervation changes in the middle and lower trapezius muscle suggest a recovering nerve injury. The surgical identification of the accessory nerve can be difficult, and preoperative review of the anatomy in a suitable textbook is appropriate. The accessory nerve should be identified at the
NOVAK and MACKINNON 223
border of the sternocleidomastoid muscle where it is just cephalic to the greater auricular nerve. It can be followed proximally to identify the branch of the accessory nerve to the sternocleidomastoid muscle, which is confirmed with direct nerve stimulation. The main accessory nerve is then followed distally into the area of injury. The injury may be incontinuity with scar tissue; in these cases, there may be no obvious separation between the proximal and distal ends of the nerve. Also in these cases, the nerve is stimulated distal to the injury, and if a contraction of the trapezius muscle is noted, then neurolysis, and not nerve repair, is performed. If no direct muscle contraction is observed, then intraoperative electrical studies will evaluate whether there is electrical conduction across the injury. If a nerve action potential is obtained, then neurolysis, and not nerve graft or repair, is performed. If no contraction or action potential is obtained, then surgical reconstruction of the nerve is indicated. With the large number of sensory nerves in this area, it is sometimes difficult to identify the distal accessory nerve. Because in these cases direct nerve stimulation cannot be used to distinguish denervated motor from sensory function, knowledge of the anatomy in this region is essential. The accessory nerve can be reliably found on the anterior surface of the trapezius muscle immediately adjacent and intimate with the muscle.13 Detaching some of the trapezius attachments from the clavicle and reflecting the trapezius laterally will also assist in identification of the distal portion of the accessory nerve. A direct nerve repair should be performed only if the proximal and distal ends of the nerve can be approximated without tension at the repair site.14 In cases where a tension-free repair cannot be made, a nerve graft should be used to restore neural continuity and thus a mechanism for reinnervation of the trapezius muscle.14 Standard microneurosurgical technique with the microscope and 9-0 microsuture is used. The head and neck are moved through a full range of motion to ensure that there is no tension on the repair or graft site. The anterior branch of the MABC nerve has proved to be an excellent donor nerve for grafting. The divided distal end of the anterior MABC nerve can be sewn end-to-side to the posterior MABC branch to decrease donor deficit of
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224 NOVAK and MACKINNON
the sensory loss on the anterior surface of the forearm. Although some would consider using the greater auricular nerve, because of the close proximity to the repair site, the broad sensory deficit in the head and neck area is objectionable for some patients. The use of the anterior branch of the MABC is associated with an acceptable scar and minimal sensory deficits.15 In our present study, good recovery of the trapezius muscle after an accessory nerve injury and subsequent repair was noted with early clinical signs of reinnervation seen at approximately 8 months and with plateau of recovery at 2 years. Similarly, others have reported good results after the repair of accessory nerve injuries.5-12 Nakamichi and Tachibana7 reported on 7 patients after an accessory nerve injury and a subsequent end-toend repair: 6 after a lymph node biopsy and 1 with removal of a bullet. All patients had relief of shoulder pain and normal trapezius muscle strength, and 4 patients reported normal shoulder function. Weisberger et al10 reported on 20 patients with cancer who underwent radical neck dissection. The group of patients who underwent immediate accessory nerve grafting was compared with patients who had no sacrifice of the accessory nerve and patients who had previously had sacrifice of the accessory nerve with no reconstruction. The best result was in those patients in whom the accessory nerve was preserved, followed by the patients who had immediate reconstruction with accessory nerve grafting. CONCLUSION The functional deficit after an accessory nerve injury is significant. In cases of a complete injury to the accessory nerve, cervical innervation of the upper trapezius muscle can lead to a false-negative conclusion regarding the injury to the accessory nerve. Electromyographic studies must carefully evaluate the middle and lower trapezius muscle.
Identification of the accessory nerve can be challenging in a scarred surgical bed, and expert knowledge of the anatomy is imperative. Nerve repair/graft reconstruction reliably yields a satisfactory result, providing good scapular rotation and thus good shoulder function. The authors would like to acknowledge Thomas H. Tung, MD, for his anatomic illustration of the posterior triangle. REFERENCES
1. Grant JCB. An Atlas of Anatomy. Baltimore: Williams & Wilkins; 1972. 2. Kendall FP, McCreary EK, Provance PG. Muscles: Testing and Function. Baltimore: Williams & Wilkins; 1993. 3. Battista AF. Complications of biopsy of the cervical lymph node. Surg Gynecol Obstet 1991;173:142-6. 4. Dailiana Z, Mehidian H, Gilbert A. Surgical anatomy of the spinal accessory nerve: is trapezius functional deficit inevitable after division of the nerve? J Hand Surg 2001; 26B:137-41. 5. Donner TR, Kline DG. Extracranial spinal accessory nerve injury. Neurosurgery 1993;32:907-10. 6. Matz PG, Barbaro NM. Diagnosis and treatment of iatrogenic spinal accessory nerve injury. Am Surg 1996;62: 682-5. 7. Nakamichi K-I, Tachibana S. Iatrogenic injury of the spinal accessory nerve: results of repair. J Bone Joint Surg 1998;80A:1616-21. 8. Ogino T, Sugawara M, Minami A, Kato H, Ohnishi N. Accessory nerve injury: conservative or surgical treatment? J Hand Surg 1991;16B:531-6. 9. Osgaard O, Eskesen V, Rosenorn J. Microsurgical repair of iatrogenic accessory nerve lesions in the posterior triangle of the neck. Acta Chir Scand 1987;153:171-3. 10. Weisberger EC, Kincaid J, Riteris J. Cable grafting of the spinal accessory nerve after radical neck dissection. Arch Otolaryngol Head Neck Surg 1998;124:377-80. 11. Wiater JM, Bigliani LU. Spinal accessory nerve injury. Clin Orthop 1999;368:5-16. 12. Williams WW, Twyman RS, Donell ST, et al. The posterior triangle and the painful shoulder: spinal accessory nerve injury. Ann R Coll Surg Engl 1996;78:521-15. 13. Pereira MT, Williams WW. The spinal accessory nerve distal to the posterior triangle. J Hand Surg 1999;24B: 368-369. 14. Mackinnon SE, Dellon AL. Surgery of the Peripheral Nerve. New York: Thieme Medical Publishers; 1988. 15. Ehretsman RL, Novak CB, McKinnon SE. Sensory recovery of nerve graft donor site. Ann Plast Surg 1999; 43:606-12.
PT, MS,
and SUSAN E. MACKINNON,
MD,
OBJECTIVE: This study assessed patient outcome following surgical reconstruction of the accessory nerve after an iatrogenic injury. STUDY DESIGN: A retrospective chart review of 8 patients was performed. RESULTS: There were 3 men and 5 women in the study, and the mean time between injury and nerve graft/repair surgery was 5 months. Four injuries were sustained during a lymph node biopsy. Electromyography revealed a complete accessory nerve injury in all cases. In 6 cases, a nerve graft was required (mean length, 3.6 cm), and in 2 cases, a direct nerve repair was possible. The trapezius muscle was successfully reinnervated in all cases. In total, full shoulder abduction was achieved in 6 cases; in the remaining 2 cases, the patients achieved shoulder abduction to 90°. CONCLUSION: Functional deficit after accessory nerve injury is significant. Nerve graft/repair reconstruction reliably yields a satisfactory result, providing good scapular rotation and thus good shoulder function. (Otolaryngol Head Neck Surg 2002;127: 221-24.)
T he accessory nerve provides motor innervation to the trapezius and sternocleidomastoid muscles.1 Injury to the accessory nerve that results in denervation of the trapezius muscle will result in a lack of scapular rotation, particularly with shoulder abduction, producing a profound functional shoulder deficit.2 Surgical exploration in the posterior triangle region of the neck places the accessory nerve at risk for iatrogenic injury3,4 (Fig 1). Early recognition and surgical reconstruction of this inFrom the Division of Plastic and Reconstructive Surgery, Washington University School of Medicine. Presented at the Annual Meeting of the American Association for Hand Surgery, Cancun, Mexico, January 10, 2002. Reprint requests: Susan E. Mackinnon, MD, Division of Plastic and Reconstructive Surgery, Suite 17424, East Pavilion, One Barnes-Jewish Hospital Plaza, St Louis, MO 63110; e-mail, [email protected]. Copyright © 2002 by the American Academy of Otolaryngology–Head and Neck Surgery Foundation, Inc. 0194-5998/2002/$35.00 ⫹ 0 23/78/126805 doi:10.1067/mhn.2002.126805
St Louis, Missouri
Fig 1. Anatomic drawing of the posterior triangle. The accessory nerve traverses within the posterior triangle between the sternocleidomastoid and trapezius muscle. At the border of the sternocleidomastoid muscle, the accessory is located above the greater auricular nerve. (Reproduced with permission from Thomas H. Tung, MD.)
jury are imperative for reinnervation of the trapezius muscle to avoid unnecessary loss of shoulder function.5-12 This study assessed patient outcome after surgery to correct an iatrogenic injury to the accessory nerve. METHODS After approval by the institutional Human Studies Committee, 8 patient charts were reviewed. Inclusion criteria included referral to a single surgeon and an accessory nerve repair or graft that was performed after an iatrogenic injury to the accessory nerve. RESULTS There was a total of 3 men and 5 women with a mean age of 50 years (SD, 10 years; age range, 39 221
222
NOVAK and MACKINNON
Otolaryngology– Head and Neck Surgery September 2002
Fig 2. A, Patient underwent a lymph node biopsy through an incision in the region of the posterior triangle and sustained an accessory nerve injury. B, After an accessory nerve graft, the patient achieved full shoulder abduction with only minimal inferior angle winging.
to 65 years). All patients had sustained an iatrogenic accessory nerve injury; 4 injuries were sustained during a lymph node biopsy, 1 during a melanoma excision, 1 during cyst excision, 1 during lipoma excision, and 1 during a reexcision of a desmoid tumor. Electrodiagnostic studies in 8 cases revealed a complete accessory nerve injury with fibrillations to the trapezius muscle and no evidence of spontaneous recovery. The mean time between injury and nerve graft/ repair surgery was 5 months (SD, 2.6 months; range, 2 to 9 months). In 6 cases, a nerve graft was needed to restore neural continuity (mean length, 3.4 cm; range, 2 to 4.5 cm), and in 2 cases, a direct nerve repair was possible. In all cases of nerve grafting, the anterior branch of the medial antebrachial cutaneous nerve (MABC) was used as the donor nerve graft. The trapezius muscle was successfully reinnervated in all 8 cases. In 6 patients, full shoulder abduction was achieved and patients reported no functional limitations of the shoulder (Fig 2). Two patients achieved improved shoulder abduction to 90° with less scapular winging than noted preoperatively. DISCUSSION Injury to the accessory nerve causing denervation of the trapezius muscle results in significant restriction of shoulder motion, particularly shoulder abduction.2 Upper trapezius muscle function loss will result in a loss of shoulder shrug, and a loss of the middle trapezius muscle function will
result in a loss of medial scapular adduction. Loss of the lower trapezius muscle will result in a loss of scapular rotation, particularly with glenohumeral abduction. Over time the lack of trapezius muscle function will result in a “droopy” shoulder because of scapular depression and downward rotation. Prolonged positioning of the shoulder girdle in this depressed position may produce patient complaints of pain, paraesthesia, and/or numbness in the upper extremity. Patient examination after an injury to the accessory nerve must include evaluation of the shoulder range of motion with attention to the associated scapular motions.2 Patients may exhibit relatively good shoulder elevation via the innervation of the upper trapezius muscle through the cervical plexus branches.4 This innervation of the upper trapezius muscle often leads to the erroneous assumption that the accessory nerve is intact or at least partially intact.4,6 Evaluation of shoulder range of motion, particularly shoulder abduction and forward flexion, will yield valuable information regarding the innervation of the trapezius muscle and the integrity of the accessory nerve. With an injury to the main branch of the accessory nerve, active shoulder abduction will be severely restricted and scapular winging will be noted. Patients may present with good shoulder flexion because of the normal functioning serratus anterior muscle, although in some patients forward flexion may also be decreased but to a lesser degree than shoulder abduction.
Otolaryngology– Head and Neck Surgery Volume 127 Number 3
The etiology of the injury is significant in considering the options for treatment. In cases where surgical exploration in the region of the posterior triangle of the neck has resulted in a lack of trapezius muscle function, an accessory nerve laceration should be suspected until proved otherwise. In surgical cases where the accessory nerve injury is recognized at the time, a primary nerve repair should be performed, and if a tension-free repair is not possible, then a nerve graft is indicated. In cases where the patient presents with ongoing pain and loss of shoulder function after a surgical procedure in the posterior triangle neck region, a thorough clinical evaluation and electrodiagnostic studies are necessary to ascertain whether a nerve injury has occurred and to identify whether there is evidence of recovery. Electrodiagnostic studies should be conducted 4 to 6 weeks after the nerve injury because muscle denervation changes will be evident at this time. Repeat electrodiagnostic studies at 3 months should show evidence of reinnervation in the upper and middle trapezius muscle or surgical exploration should be considered. Many needle electromyographic studies examine only the upper trapezius muscle and a false-negative result may occur if the upper trapezius is innervated by the cervical branches of the accessory nerve. For a complete electromyographic study, the upper, middle, and lower trapezius muscles should be examined. In cases of severe atrophy of the middle and lower trapezius muscles, the electromyographer must take care to place the needle in only the trapezius muscle and not the underlying innervated muscles. For example, normal studies of the upper trapezius with denervation changes and no signs of reinnervation in the middle and lower trapezius muscle at 3 months do not imply recovery. It suggests innervation of the upper trapezius muscle by the cervical plexus and a complete injury to the main accessory nerve. By contrast, changes in fibrillations and motor unit potentials in the upper trapezius muscle with the same denervation changes in the middle and lower trapezius muscle suggest a recovering nerve injury. The surgical identification of the accessory nerve can be difficult, and preoperative review of the anatomy in a suitable textbook is appropriate. The accessory nerve should be identified at the
NOVAK and MACKINNON 223
border of the sternocleidomastoid muscle where it is just cephalic to the greater auricular nerve. It can be followed proximally to identify the branch of the accessory nerve to the sternocleidomastoid muscle, which is confirmed with direct nerve stimulation. The main accessory nerve is then followed distally into the area of injury. The injury may be incontinuity with scar tissue; in these cases, there may be no obvious separation between the proximal and distal ends of the nerve. Also in these cases, the nerve is stimulated distal to the injury, and if a contraction of the trapezius muscle is noted, then neurolysis, and not nerve repair, is performed. If no direct muscle contraction is observed, then intraoperative electrical studies will evaluate whether there is electrical conduction across the injury. If a nerve action potential is obtained, then neurolysis, and not nerve graft or repair, is performed. If no contraction or action potential is obtained, then surgical reconstruction of the nerve is indicated. With the large number of sensory nerves in this area, it is sometimes difficult to identify the distal accessory nerve. Because in these cases direct nerve stimulation cannot be used to distinguish denervated motor from sensory function, knowledge of the anatomy in this region is essential. The accessory nerve can be reliably found on the anterior surface of the trapezius muscle immediately adjacent and intimate with the muscle.13 Detaching some of the trapezius attachments from the clavicle and reflecting the trapezius laterally will also assist in identification of the distal portion of the accessory nerve. A direct nerve repair should be performed only if the proximal and distal ends of the nerve can be approximated without tension at the repair site.14 In cases where a tension-free repair cannot be made, a nerve graft should be used to restore neural continuity and thus a mechanism for reinnervation of the trapezius muscle.14 Standard microneurosurgical technique with the microscope and 9-0 microsuture is used. The head and neck are moved through a full range of motion to ensure that there is no tension on the repair or graft site. The anterior branch of the MABC nerve has proved to be an excellent donor nerve for grafting. The divided distal end of the anterior MABC nerve can be sewn end-to-side to the posterior MABC branch to decrease donor deficit of
Otolaryngology– Head and Neck Surgery September 2002
224 NOVAK and MACKINNON
the sensory loss on the anterior surface of the forearm. Although some would consider using the greater auricular nerve, because of the close proximity to the repair site, the broad sensory deficit in the head and neck area is objectionable for some patients. The use of the anterior branch of the MABC is associated with an acceptable scar and minimal sensory deficits.15 In our present study, good recovery of the trapezius muscle after an accessory nerve injury and subsequent repair was noted with early clinical signs of reinnervation seen at approximately 8 months and with plateau of recovery at 2 years. Similarly, others have reported good results after the repair of accessory nerve injuries.5-12 Nakamichi and Tachibana7 reported on 7 patients after an accessory nerve injury and a subsequent end-toend repair: 6 after a lymph node biopsy and 1 with removal of a bullet. All patients had relief of shoulder pain and normal trapezius muscle strength, and 4 patients reported normal shoulder function. Weisberger et al10 reported on 20 patients with cancer who underwent radical neck dissection. The group of patients who underwent immediate accessory nerve grafting was compared with patients who had no sacrifice of the accessory nerve and patients who had previously had sacrifice of the accessory nerve with no reconstruction. The best result was in those patients in whom the accessory nerve was preserved, followed by the patients who had immediate reconstruction with accessory nerve grafting. CONCLUSION The functional deficit after an accessory nerve injury is significant. In cases of a complete injury to the accessory nerve, cervical innervation of the upper trapezius muscle can lead to a false-negative conclusion regarding the injury to the accessory nerve. Electromyographic studies must carefully evaluate the middle and lower trapezius muscle.
Identification of the accessory nerve can be challenging in a scarred surgical bed, and expert knowledge of the anatomy is imperative. Nerve repair/graft reconstruction reliably yields a satisfactory result, providing good scapular rotation and thus good shoulder function. The authors would like to acknowledge Thomas H. Tung, MD, for his anatomic illustration of the posterior triangle. REFERENCES
1. Grant JCB. An Atlas of Anatomy. Baltimore: Williams & Wilkins; 1972. 2. Kendall FP, McCreary EK, Provance PG. Muscles: Testing and Function. Baltimore: Williams & Wilkins; 1993. 3. Battista AF. Complications of biopsy of the cervical lymph node. Surg Gynecol Obstet 1991;173:142-6. 4. Dailiana Z, Mehidian H, Gilbert A. Surgical anatomy of the spinal accessory nerve: is trapezius functional deficit inevitable after division of the nerve? J Hand Surg 2001; 26B:137-41. 5. Donner TR, Kline DG. Extracranial spinal accessory nerve injury. Neurosurgery 1993;32:907-10. 6. Matz PG, Barbaro NM. Diagnosis and treatment of iatrogenic spinal accessory nerve injury. Am Surg 1996;62: 682-5. 7. Nakamichi K-I, Tachibana S. Iatrogenic injury of the spinal accessory nerve: results of repair. J Bone Joint Surg 1998;80A:1616-21. 8. Ogino T, Sugawara M, Minami A, Kato H, Ohnishi N. Accessory nerve injury: conservative or surgical treatment? J Hand Surg 1991;16B:531-6. 9. Osgaard O, Eskesen V, Rosenorn J. Microsurgical repair of iatrogenic accessory nerve lesions in the posterior triangle of the neck. Acta Chir Scand 1987;153:171-3. 10. Weisberger EC, Kincaid J, Riteris J. Cable grafting of the spinal accessory nerve after radical neck dissection. Arch Otolaryngol Head Neck Surg 1998;124:377-80. 11. Wiater JM, Bigliani LU. Spinal accessory nerve injury. Clin Orthop 1999;368:5-16. 12. Williams WW, Twyman RS, Donell ST, et al. The posterior triangle and the painful shoulder: spinal accessory nerve injury. Ann R Coll Surg Engl 1996;78:521-15. 13. Pereira MT, Williams WW. The spinal accessory nerve distal to the posterior triangle. J Hand Surg 1999;24B: 368-369. 14. Mackinnon SE, Dellon AL. Surgery of the Peripheral Nerve. New York: Thieme Medical Publishers; 1988. 15. Ehretsman RL, Novak CB, McKinnon SE. Sensory recovery of nerve graft donor site. Ann Plast Surg 1999; 43:606-12.