HAND/PERIPHERAL NERVE Distal Nerve Transfers Are Effective in Treating Patients with Upper Trunk Obstetrical Brachial Plexus Injuries: An Early Experience Adil Ladak, M.D. Michael Morhart, M.D. Kathleen O’Grady, B.Sc., O.T. Joshua N. Wong, M.D. K. Ming Chan, M.D. M. Joe Watt, M.D. Jaret L. Olson, M.D. Edmonton, Alberta, Canada
Background: Current surgical management of obstetrical brachial plexus injury is primary reconstruction with sural nerve grafts. Recently, the nerveto-nerve transfer technique has been used to treat brachial plexus injury in adults, affording the benefit of distal coaptations that minimize regenerative distance. The purpose of this study was to test the hypothesis that nerve transfers are effective in reconstructing isolated upper trunk obstetrical brachial plexus injuries. Methods: Ten patients aged 10 to 18 months were treated with three nerve transfers: spinal accessory nerve to the suprascapular nerve for shoulder abduction and external rotation; a radial to axillary nerve for shoulder abduction; and ulnar or median nerve transfer to the musculocutaneous nerve for elbow flexion. Patients were assessed preoperatively and postoperatively using the Active Movement Scale. All patients were followed regularly for up to 2 years. Results: Improvement in elbow and shoulder function was observed between 6 and 24 months. By 6 months, all patients passed the cookie test. At 24 months, shoulder abduction improved from 3.7 ± 0.6 to 5.0 ± 0.5, shoulder external rotation from 1.8 ± 0.4 to 4.3 ± 0.6, shoulder flexion from 3.7 ± 0.5 to 5.4 ± 0.5, elbow flexion from 3.7 ± 0.6 to 6.3 ± 0.2, and forearm supination from 2.1 ± 0.4 to 5.9 ± 0.2. There was no clinically appreciable donor-site morbidity. Conclusions: Nerve transfers reduced operative times compared with traditional nerve grafting procedures. Those patients showed significant gains in Active Movement Scale score by 24 months postoperatively, comparable to results achieved by nerve grafting. These findings support nerve transfers as a potential alternative treatment option for upper trunk obstetrical brachial plexus injuries. (Plast. Reconstr. Surg. 132: 985e, 2013.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.
O
bstetrical brachial plexus palsies result from closed traction injury during the birthing process. The degree to which the plexus is injured varies, with equally varied prognosis for functional recovery. One widely used determinant of From the Divisions of Plastic and Reconstructive Surgery and Physical Medicine and Rehabilitation, University of Alberta. Received for publication September 2, 2012; accepted June 5, 2013. Presented at the 16th Congress of the International Confederation for Plastic, Reconstructive and Aesthetic Surgery, in Vancouver, British Columbia, Canada, May 22 through 27, 2011; and the American Society for Peripheral Nerve Annual Meeting, in Las Vegas, Nevada, January 13 through 15, 2012. Copyright © 2013 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0b013e3182a97e13
surgical intervention is the Active Movement Scale.1 This scale quantifies the range of motion in the shoulder, elbow, wrist, and digits, providing a comprehensive analysis of upper limb function. An additional determinant of surgical intervention is the cookie test, which measures biceps function through the ability of a child to bring a cookie to his or her mouth using only their biceps muscle while keeping the shoulder completely adducted. Marcus and Clarke consider the inability to pass the cookie test by 9 months of age to be an indication for surgery.2 The current standard of care at most centers in North America is excision of the neuroma and
Disclosure: The authors have no financial interest to declare in relation to the content of this article.
www.PRSJournal.com
985e
Plastic and Reconstructive Surgery • December 2013 nerve grafting with the sural nerve. This technique is associated with several disadvantages, including the need for surgical dissection of the neck, harvest of bilateral sural nerve grafts with resultant donor-site numbness, a relatively long postoperative hospital stay, and a decline in postoperative function following the procedure, resulting in a prolonged recovery time. In contrast, distal nerve transfer is a relatively new technique in peripheral nerve surgery that affords many benefits over traditional nerve grafting, especially in proximal nerve injuries, including nerve coaptation in closer proximity to muscle, motor-to-motor coaptation, and faster recovery time.3 Nerve transfers for reconstruction of brachial plexus injuries is well established in the adult population, with many reports supporting their use as a first-line treatment for reconstruction of brachial plexus injuries instead of nerve grafting.3,4 However, the use of nerve transfers in obstetrical brachial plexus patients is not well established. Few reports in the literature have examined the potential role of nerve transfers to restore specific functional deficits, including shoulder and elbow function.5–7 To date, there is no study examining the role of nerve transfers as a potential first-line treatment option for complete reconstruction of isolated obstetrical upper trunk pattern injuries. The goal of this study was to examine the motor outcomes achieved using three nerve transfers: spinal accessory nerve to suprascapular nerve, radial nerve to axillary nerve, and ulnar or median nerve to musculocutaneous nerve. We hypothesize that distal nerve transfers as a sole means of reconstructing isolated upper trunk obstetrical brachial plexus injuries are effective in restoring shoulder and elbow function.
PATIENTS AND METHODS Patient Selection This study was conducted in adherence to the ethical principles outlined in the World Medical Association Declaration of Helsinki and was approved by the human research ethics board at the University of Alberta. Children with isolated upper trunk obstetrical brachial plexus injuries were recruited. From birth, infants were evaluated at the brachial plexus clinic at the Glenrose Rehabilitation Hospital by a multidisciplinary team. Written and verbal informed consent regarding the operation was obtained from the parent or guardian of each child. The arm function of each child was graded independently using the Active
986e
Movement Scale by occupational and physical therapists who were not involved in the surgical management of the children. Inclusion criteria for the study included having an isolated upper trunk injury based on clinical examination findings, supported by normal needle electromyographic evaluation of the triceps muscle, and normal elbow extension (Active Movement Scale score of 7), wrist flexion, and a failed cookie test at 9 months of age. Children were carefully examined for evidence of middle or lower trunk deficits. Intraoperative studies suggest that C7 and the middle trunk are prime contributors to innervation of the triceps muscle.8,9 Therefore, children with elbow extension abnormality were excluded from the study. To eliminate lower trunk deficits, those with wrist and hand abnormalities were also excluded. In cases where the physical examination findings were equivocal, additional supporting evidence was sought through needle electromyographic evaluation and computed tomographic myelography. Surgical Procedure The procedure used in this study consisted of three distal nerve transfers. First, a distal branch of the spinal accessory nerve (identified using intraoperative nerve stimulation) was transferred to the suprascapular nerve for shoulder abduction and external rotation. A posterior approach was used to expose the suprascapular nerve at the level of the scapular ligament (Fig. 1). Next, a motor branch of the radial nerve to the lateral triceps was transferred to the axillary nerve close to its neuromuscular junction for shoulder abduction (Fig. 1). Extra care was taken to avoid coaptation with the sensory component. The third was the Oberlin transfer, using a unifascicular transfer of a redundant motor branch to the flexor carpi ulnaris of the ulnar nerve to the musculocutaneous nerve innervating the biceps brachii muscle (Fig. 2).10,11 In cases where no dominant flexor carpi ulnaris nerve fascicle could be isolated, a redundant branch of the median nerve to the flexor carpi radialis was used.11 All nerve coaptations were performed under 2× loupe magnification using quick-set Tisseel Fibrin Sealant (Baxter Healthcare Corp., Westlake Village, Calif.). Once applied, the glue was allowed to set for 10 minutes before closure of the incision sites. Postoperatively, a modified sling using elastic bandage was applied to immobilize the child’s arm in full shoulder adduction and 90 degrees of elbow flexion for 3 weeks before active physiotherapy was initiated.
Volume 132, Number 6 • Nerve Transfers in Brachial Plexus Injury
Fig. 1. Spinal accessory–to-suprascapular nerve and radial-to-axillary nerve transfers for reconstruction of shoulder function. A posterior approach was used to expose the suprascapular nerve that included releasing it from the suprascapular notch. A dorsal muscle-splitting longitudinal incision along the upper arm was used to expose the radial nerve.
Evaluation To avoid surgeon selection bias, an independent therapist used the Active Movement Scale to evaluate patients preoperatively and postoperatively.1 Shoulder function (including abduction, flexion, and external rotation), elbow flexion, and forearm supination were examined. Donor nerve function, including elbow extension and wrist flexion, was also tested. Scoring was performed immediately
preoperatively and then at 3, 6, 9, and 12 months postoperatively on all children. At the time of submission of this article for publication, eight of the 10 patients had passed the 2-year postoperative stage and were also evaluated at 24 months. Statistical Analysis Statistical analysis was performed using SPSS 14.0 software (SPSS, Inc., Chicago, Ill.). Values
Fig. 2. A unifascicular transfer rerouting a redundant motor branch of the ulnar nerve that innervates the flexor carpi ulnaris muscle to the musculocutaneous nerve. If unavailable, a redundant branch of the median nerve to the flexor carpi radialis muscle was used for the transfer.
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Plastic and Reconstructive Surgery • December 2013 Table 1. Preoperative and Postoperative Active Movement Scale Scores for Shoulder and Elbow Function following the Triple Nerve Transfer Procedure* Movement Shoulder abduction Shoulder external rotation Shoulder flexion Elbow flexion Forearm supination
Preoperative Score
Postoperative Score (1 yr)
Postoperative Score (2 yr)
Change in Score
Preoperative versus 2 Yr Postoperative (p)
3.7 ± 0.6 1.8 ± 0.4 3.7 ± 0.5 3.7 ± 0.6 2.1 ± 0.4
4.7 ± 0.4 3.8 ± 0.4 5.4 ± 0.4 6.2 ± 0.1 4.8 ± 0.4
5.0 ± 0.5 4.3 ± 0.6 5.4 ± 0.5 6.3 ± 0.2 5.9 ± 0.2
1.7 2.5 1.8 2.7 3.8
Background: Current surgical management of obstetrical brachial plexus injury is primary reconstruction with sural nerve grafts. Recently, the nerveto-nerve transfer technique has been used to treat brachial plexus injury in adults, affording the benefit of distal coaptations that minimize regenerative distance. The purpose of this study was to test the hypothesis that nerve transfers are effective in reconstructing isolated upper trunk obstetrical brachial plexus injuries. Methods: Ten patients aged 10 to 18 months were treated with three nerve transfers: spinal accessory nerve to the suprascapular nerve for shoulder abduction and external rotation; a radial to axillary nerve for shoulder abduction; and ulnar or median nerve transfer to the musculocutaneous nerve for elbow flexion. Patients were assessed preoperatively and postoperatively using the Active Movement Scale. All patients were followed regularly for up to 2 years. Results: Improvement in elbow and shoulder function was observed between 6 and 24 months. By 6 months, all patients passed the cookie test. At 24 months, shoulder abduction improved from 3.7 ± 0.6 to 5.0 ± 0.5, shoulder external rotation from 1.8 ± 0.4 to 4.3 ± 0.6, shoulder flexion from 3.7 ± 0.5 to 5.4 ± 0.5, elbow flexion from 3.7 ± 0.6 to 6.3 ± 0.2, and forearm supination from 2.1 ± 0.4 to 5.9 ± 0.2. There was no clinically appreciable donor-site morbidity. Conclusions: Nerve transfers reduced operative times compared with traditional nerve grafting procedures. Those patients showed significant gains in Active Movement Scale score by 24 months postoperatively, comparable to results achieved by nerve grafting. These findings support nerve transfers as a potential alternative treatment option for upper trunk obstetrical brachial plexus injuries. (Plast. Reconstr. Surg. 132: 985e, 2013.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.
O
bstetrical brachial plexus palsies result from closed traction injury during the birthing process. The degree to which the plexus is injured varies, with equally varied prognosis for functional recovery. One widely used determinant of From the Divisions of Plastic and Reconstructive Surgery and Physical Medicine and Rehabilitation, University of Alberta. Received for publication September 2, 2012; accepted June 5, 2013. Presented at the 16th Congress of the International Confederation for Plastic, Reconstructive and Aesthetic Surgery, in Vancouver, British Columbia, Canada, May 22 through 27, 2011; and the American Society for Peripheral Nerve Annual Meeting, in Las Vegas, Nevada, January 13 through 15, 2012. Copyright © 2013 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0b013e3182a97e13
surgical intervention is the Active Movement Scale.1 This scale quantifies the range of motion in the shoulder, elbow, wrist, and digits, providing a comprehensive analysis of upper limb function. An additional determinant of surgical intervention is the cookie test, which measures biceps function through the ability of a child to bring a cookie to his or her mouth using only their biceps muscle while keeping the shoulder completely adducted. Marcus and Clarke consider the inability to pass the cookie test by 9 months of age to be an indication for surgery.2 The current standard of care at most centers in North America is excision of the neuroma and
Disclosure: The authors have no financial interest to declare in relation to the content of this article.
www.PRSJournal.com
985e
Plastic and Reconstructive Surgery • December 2013 nerve grafting with the sural nerve. This technique is associated with several disadvantages, including the need for surgical dissection of the neck, harvest of bilateral sural nerve grafts with resultant donor-site numbness, a relatively long postoperative hospital stay, and a decline in postoperative function following the procedure, resulting in a prolonged recovery time. In contrast, distal nerve transfer is a relatively new technique in peripheral nerve surgery that affords many benefits over traditional nerve grafting, especially in proximal nerve injuries, including nerve coaptation in closer proximity to muscle, motor-to-motor coaptation, and faster recovery time.3 Nerve transfers for reconstruction of brachial plexus injuries is well established in the adult population, with many reports supporting their use as a first-line treatment for reconstruction of brachial plexus injuries instead of nerve grafting.3,4 However, the use of nerve transfers in obstetrical brachial plexus patients is not well established. Few reports in the literature have examined the potential role of nerve transfers to restore specific functional deficits, including shoulder and elbow function.5–7 To date, there is no study examining the role of nerve transfers as a potential first-line treatment option for complete reconstruction of isolated obstetrical upper trunk pattern injuries. The goal of this study was to examine the motor outcomes achieved using three nerve transfers: spinal accessory nerve to suprascapular nerve, radial nerve to axillary nerve, and ulnar or median nerve to musculocutaneous nerve. We hypothesize that distal nerve transfers as a sole means of reconstructing isolated upper trunk obstetrical brachial plexus injuries are effective in restoring shoulder and elbow function.
PATIENTS AND METHODS Patient Selection This study was conducted in adherence to the ethical principles outlined in the World Medical Association Declaration of Helsinki and was approved by the human research ethics board at the University of Alberta. Children with isolated upper trunk obstetrical brachial plexus injuries were recruited. From birth, infants were evaluated at the brachial plexus clinic at the Glenrose Rehabilitation Hospital by a multidisciplinary team. Written and verbal informed consent regarding the operation was obtained from the parent or guardian of each child. The arm function of each child was graded independently using the Active
986e
Movement Scale by occupational and physical therapists who were not involved in the surgical management of the children. Inclusion criteria for the study included having an isolated upper trunk injury based on clinical examination findings, supported by normal needle electromyographic evaluation of the triceps muscle, and normal elbow extension (Active Movement Scale score of 7), wrist flexion, and a failed cookie test at 9 months of age. Children were carefully examined for evidence of middle or lower trunk deficits. Intraoperative studies suggest that C7 and the middle trunk are prime contributors to innervation of the triceps muscle.8,9 Therefore, children with elbow extension abnormality were excluded from the study. To eliminate lower trunk deficits, those with wrist and hand abnormalities were also excluded. In cases where the physical examination findings were equivocal, additional supporting evidence was sought through needle electromyographic evaluation and computed tomographic myelography. Surgical Procedure The procedure used in this study consisted of three distal nerve transfers. First, a distal branch of the spinal accessory nerve (identified using intraoperative nerve stimulation) was transferred to the suprascapular nerve for shoulder abduction and external rotation. A posterior approach was used to expose the suprascapular nerve at the level of the scapular ligament (Fig. 1). Next, a motor branch of the radial nerve to the lateral triceps was transferred to the axillary nerve close to its neuromuscular junction for shoulder abduction (Fig. 1). Extra care was taken to avoid coaptation with the sensory component. The third was the Oberlin transfer, using a unifascicular transfer of a redundant motor branch to the flexor carpi ulnaris of the ulnar nerve to the musculocutaneous nerve innervating the biceps brachii muscle (Fig. 2).10,11 In cases where no dominant flexor carpi ulnaris nerve fascicle could be isolated, a redundant branch of the median nerve to the flexor carpi radialis was used.11 All nerve coaptations were performed under 2× loupe magnification using quick-set Tisseel Fibrin Sealant (Baxter Healthcare Corp., Westlake Village, Calif.). Once applied, the glue was allowed to set for 10 minutes before closure of the incision sites. Postoperatively, a modified sling using elastic bandage was applied to immobilize the child’s arm in full shoulder adduction and 90 degrees of elbow flexion for 3 weeks before active physiotherapy was initiated.
Volume 132, Number 6 • Nerve Transfers in Brachial Plexus Injury
Fig. 1. Spinal accessory–to-suprascapular nerve and radial-to-axillary nerve transfers for reconstruction of shoulder function. A posterior approach was used to expose the suprascapular nerve that included releasing it from the suprascapular notch. A dorsal muscle-splitting longitudinal incision along the upper arm was used to expose the radial nerve.
Evaluation To avoid surgeon selection bias, an independent therapist used the Active Movement Scale to evaluate patients preoperatively and postoperatively.1 Shoulder function (including abduction, flexion, and external rotation), elbow flexion, and forearm supination were examined. Donor nerve function, including elbow extension and wrist flexion, was also tested. Scoring was performed immediately
preoperatively and then at 3, 6, 9, and 12 months postoperatively on all children. At the time of submission of this article for publication, eight of the 10 patients had passed the 2-year postoperative stage and were also evaluated at 24 months. Statistical Analysis Statistical analysis was performed using SPSS 14.0 software (SPSS, Inc., Chicago, Ill.). Values
Fig. 2. A unifascicular transfer rerouting a redundant motor branch of the ulnar nerve that innervates the flexor carpi ulnaris muscle to the musculocutaneous nerve. If unavailable, a redundant branch of the median nerve to the flexor carpi radialis muscle was used for the transfer.
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Plastic and Reconstructive Surgery • December 2013 Table 1. Preoperative and Postoperative Active Movement Scale Scores for Shoulder and Elbow Function following the Triple Nerve Transfer Procedure* Movement Shoulder abduction Shoulder external rotation Shoulder flexion Elbow flexion Forearm supination
Preoperative Score
Postoperative Score (1 yr)
Postoperative Score (2 yr)
Change in Score
Preoperative versus 2 Yr Postoperative (p)
3.7 ± 0.6 1.8 ± 0.4 3.7 ± 0.5 3.7 ± 0.6 2.1 ± 0.4
4.7 ± 0.4 3.8 ± 0.4 5.4 ± 0.4 6.2 ± 0.1 4.8 ± 0.4
5.0 ± 0.5 4.3 ± 0.6 5.4 ± 0.5 6.3 ± 0.2 5.9 ± 0.2
1.7 2.5 1.8 2.7 3.8
