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Pectoralis major transfer for serratus anterior paralysis
Pectoralis major transfer for serratus anterior paralysis Scott P. Steinmann, MD,a,b and Michael B. Wood, MD,a,b Rochester, MN
Serratus anterior paralysis can result in winging of the scapula and weakness of arm elevation. The etiology of the condition is injury to the long thoracic nerve. There are many proposed causes of long thoracic nerve injury including acute trauma, Parsonage-Turner syndrome, or viral illness. The long length of the long thoracic nerve makes it prone to compression injury along the chest wall. Most patients recover nerve function with conservative treatment. In those in whom nerve function fails to recover, surgical treatment involving pectoralis major transfer may be beneficial. In this study 9 patients underwent pectoralis major transfer with a fascia lata extension graft. The symptoms of most were improved, with correction of the winging and improved movement in the affected shoulder. (J Shoulder Elbow Surg 2003;12:555-60.)
P
aralysis of the serratus anterior muscle results in winging of the scapula with attempted arm elevation. This is best noticed when the patient is viewed from behind. Those with serratus anterior paralysis complain of pain in the shoulder, weakness of arm elevation, and shoulder girdle muscle fatigue. The etiology of the condition is injury to the long thoracic nerve, which is the sole innervation of the serratus anterior. The long thoracic nerve is formed primarily from contributions of nerve roots C5 and C6 with additional innervation from C7.11,12 There are many described causes of a long thoracic nerve lesion including acute trauma, repetitive trauma, surgical positioning, viral illness, and Parsonage-Turner syndrome or paralytic brachial neuritis.6,8,14,15,21,28 Excluding penetrating trauma, a traction or compression mechanism of injury is assumed in many cases to account for damage to the long thoracic nerve. Several investigators have performed dissections to determine where the nerve may be prone to impingement or compression injury. From Orthopaedic Surgery, Mayo Medical School,a and Hand and Microsurgery, Department of Orthopaedics, Mayo Clinic.b Reprint requests: Scott P. Steinmann, MD, Mayo Clinic, 200 First Street SW, Rochester, MN 55905. (E-mail: steinmann.scott @mayo.edu). Copyright © 2003 by Journal of Shoulder and Elbow Surgery Board of Trustees. 1058-2746/2003/$35.00 ⫹ 0 doi:10.1016/S1058-2746(03)00174-5
Some believe the nerve is vulnerable to traction or compression as it crosses the second rib7,11 or compression as it passes through the middle scalene muscle. Other theories include traction to the nerve as the head is rotated and laterally tilted away from the shoulder8 or compression at the anterior inferior border of the scapula.16 In addition, the considerable length of the nerve, measuring approximately 20 cm,16 and its superficial location along the lateral chest from the eighth to the ninth rib increase its vulnerability. The vast majority of those with closed injury recover spontaneously over the course of several months with conservative treatment.14 By 6 to 12 months, most have recovered. Occasionally, patients are seen who do not have clinical improvement with extended conservative treatment of greater than 1 year. Electromyographic studies can be used to detect any subclinical recovery of the muscle during this waiting period. When no recovery has been documented after prolonged conservative treatment, surgical reconstruction can be considered. This study examines the clinical results in a consecutive series of patients undergoing pectoralis major transfer to the vertebral border of the scapula. MATERIALS AND METHODS Nine patients with the diagnosis of serratus anterior paralysis were identified through a computerized search of our institutional database. Exclusion criteria included a follow-up period of less than 1 year or lack of preoperative electromyographic documentation of complete serratus anterior denervation. The evaluation proposal was approved by the Institutional Review Board. All patients were evaluated by an impartial observer (S.P.S.) not involved with their direct care by review of the last clinic note and patients’ responses to a questionnaire and personal examination. Evaluations included shoulder range of motion, pain, presence or absence of scapular winging, shoulder strength, presence of complications, and work status. Winging was identified if, upon inspection and observation from behind the patient, visible protrusion of the scapula occurred with the initiation of forward arm elevation. At final follow-up, those patients returning were invited to undergo biomechanical testing in our biomechanics laboratory. Five of nine patients agreed to further evaluation. Biomechanical testing included Cybex II strength testing (Lumex, Ronkonkoma, NY). Isometric strength was measured in adduction, abduction, external rotation, and inter-
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nal rotation. Results were expressed as a percentage of the unaffected shoulder.1 In addition, in these 5 patients, range of motion was measured by the 3-space Isotrak system (Polhemus Navigation Sciences Division, Colchester, VT). This system allows real-time monitoring of complex shoulder motion. The device is based on the electromagnetic tracking concept in which a set of magnetic sensors are placed on the patient’s trunk, shoulders, and arms. As motion is initiated, range of motion of the upper extremity is continually recorded.20 In addition to standard shoulder motion parameters of forward elevation, external rotation, and internal rotation, these 5 patients were asked to perform a series of activities of daily living requiring progressively greater shoulder work. These included reaching the opposite shoulder, touching the top of the head and sacrum, and lifting a pitcher to waist height, eye height, and just above head height while standing. Results were expressed as a percentage of the unaffected shoulder. The 5 patients undergoing biomechanical testing were also evaluated with the American Shoulder and Elbow Surgeons patient self-evaluation form.25 There were 5 men and 4 women with a mean age of 33.6 years (range, 21-47 years). The duration of symptoms averaged 34 months (range, 24-60 months). Serratus anterior palsy was a result of acute trauma in 5 cases, minor trauma in 2 cases, and iatrogenic injury during thoracic surgery in 2 patients. Of 9 patients, 5 had preinjury occupations requiring heavy labor whereas 4 patients did office work. Two had undergone previous surgery including carpal tunnel release and cervical spinal fusion. All had complained preoperatively of chronic pain and early fatigue in the shoulder with arm elevation during daily activities.
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Figure 1 Anterior view of shoulder axilla. The white arrow demonstrates the pectoralis major detached from the humerus, ready for attachment to a fascia lata graft.
Surgical technique The operation involved detachment of the pectoralis major from the humerus and reattachment at the junction of the middle and distal third of the lateral scapula with a fascia lata extension graft. The patient was placed in the lateral decubitus position with the use of a standard axillary roll pad, with the head of the table elevated 15° to 20°. Early in the series, an incision was made in the axilla over the palpable lateral margin of the pectoralis major, which was curved across the axilla to the inferior pole of the scapula. Later, a limited technique was used involving a 4-cm axillary incision and a second incision parallel to the scapular inferior vertebral border approximately 5 cm in length. The pectoralis major was detached from the humerus (Figure 1). A portion of fascia lata, measuring approximately 5 ⫻ 15 cm, was then harvested from the thigh via a longitudinal incision. (Harvest of the fascia lata may be performed by a second surgical team while the pectoralis major is dissected.) This was rolled upon itself and two No. 5 braided nonabsorbable sutures placed in a running fashion throughout the length of the graft. One end of the graft was then sutured to the tendon stump of the pectoralis major. A 1-cm-wide hole was made with a burr on the inferior pole of the scapula at the junction of the middle and distal third. The fascia lata graft was placed through the hole and sutured back upon itself while the stump of the pectoralis major tendon was pulled to the edge of the scapula (Figures 2, 3, and 4). The tendon of the pectoralis
Figure 2 Anterior view. The pectoralis major has been detached from the humerus and attached to the inferior scapula with a fascia lata graft.
major contacted the scapula. Ideally, the fascia lata was used to augment the pectoralis major tendon and not to act as an extension. If used as an extension, the avascular fascia lata may over time be at risk for elongation or rupture. When the sutures were being tied, the scapula was held firmly anteriorly because the graft tended to stretch slightly over time. After standard surgical closure and drainage, the arm was placed into a Velpeau sling and immobilized for 6 weeks. For 5 of the patients in this series, the arm was initially placed into a shoulder spica cast in neutral rotation. During the postoperative period, only gentle pendulum exercises were performed. At 6 weeks postoperatively, the cast or sling was removed and progressive active and passive exercises to the shoulder girdle initiated. At 12
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Table I Definition of excellent, good, and poor results Excellent: ROM within 90% of unaffected side No winging No pain Strength 5/5 Good: ROM withing 75%-90% of unaffected side Slight winging Mild pain Moderate weakness 4/5 Poor: ROM ⬍75% of unaffected side Persistent winging Moderate or severe pain Strength 3/5 ROM, Range of motion.
Figure 3 Posterior view. The pectoralis major has been passed posteriorly and connected to the scapula with a fascia lata graft. The native tendon of the pectoralis major will typically abut the edge of the scapula.
Figure 4 Patient in lateral decubitus position. The black arrow demonstrates the anterior axillary incision; the white arrow demonstrates the incision over the inferior scapula. A fascia lata graft is passed from anterior to posterior incision.
weeks postoperatively, return to noncontact athletic activities was permitted. At 6 months, resumption of heavy lifting or work was allowed.
RESULTS At final follow-up, patients’ results were graded as either excellent, good, or poor (Table I). A patient with an excellent result had total range of motion within 90% of the unaffected side, no visible scapular winging, no pain, and normal strength. A patient with a good result had range of motion between 75% to 90% of the unaffected side, minimal winging, mild
pain, and minimal weakness. A patient with a poor result had range of motion of less than 75% of the unaffected side, winging unchanged from preoperatively, severe pain, and significantly less strength than the unaffected side. Follow-up averaged 70 months (range, 12-168 months) (Table II). Preoperatively, the patients averaged 90° forward elevation with 4/5 weakness on muscle strength testing and 50° external rotation. Postoperatively, the nine patients were noted to have mean forward elevation of 144° (range, 53°-165°) and 52° external rotation (range, 25°-88°). Five patients had no pain, two patients had slight pain, and two patients had moderate pain. None had severe pain. Postoperatively, four patients had normal strength and five were graded 4/5. Postoperatively, there were three complications in two patients (patients 5 and 9). In both adhesive capsulitis developed in the immediate postoperative period. One (patient 9) also required drainage of a thigh seroma after fascia lata grafting. Both patients had been treated in a shoulder spica cast. Apparent resolution of winging occurred in six patients. Three had slight winging. Of the seven who were employed outside the home, five were able to return to work but two were unable to return to work because of pain and poor function. Isometric strength evaluation in the five patients undergoing biomechanical testing is presented in Table III. Mean isometric strength of adduction was lowest at 59% of the unaffected side, followed by external rotation rated at 62%, abduction 68%, and internal rotation 73%. Overall, two of these patients were rated as excellent, one as good, and two as poor. Three-space Isotrak measurements of humeral elevation during specified activities of daily living revealed the greatest difference in external rotation (mean, 64% of unaffected side) and with forward
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Table II Patient characteristics Duration of symptoms Patient Age (mos) No. (y) Sex Side
Cause
Return to ElectroFollow-up Final myography Occupation (mo) Result Winging work Complications
1
32
M
R
30
Fall
⫹
2 3 4 5
23 47 39 44
F F M F
R R R R
36 60 24 24
6 7 8 9
37 21 26 47
M F M M
R R R R
24 48 36 24
Throwing Seizure Iatrogenic Motor vehicle accident Fall Iatrogenic Heavy lifting Crush injury
48
Excellent
None
Yes
No
⫹ ⫹ ⫹ ⫹
Manual laborer Waitress Housewife Repairman Cook
168 132 48 12
Excellent Good Poor Poor
None Slight None Slight
Yes Yes No Yes
⫹ ⫹ ⫹ ⫹
Repairman Singer Carpenter Carpenter
48 24 84 60
Excellent Good Excellent Poor
None Slight None None
Yes Yes Yes No
No No No Adhesive capsulitis No No No Thigh seroma/ adhesive capsulitis
Table III Isometric strength measurements (percentage of unaffected side) Patient No. 2 3 4 5 6
Abduction
Adduction
External rotation
Internal rotation
53 100 61 45 79
58 73 68 42 52
64 100 42 25 80
64 100 67 58 76
elevation of the arm (84% of unaffected side) (Table IV). The other activities were less demanding and ranged from 85% to 100% of the unaffected side. The American Shoulder and Elbow Surgeons shoulder index score averaged 67.4 out of a possible 100. Overall, there were four excellent, two good, and three poor results. Those with excellent results included three manual laborers with a mean follow-up of 87 months (range, 24-168 months). The two patients with a good result both had slight winging at follow-up (132 months and 24 months, respectively) but had returned to their previous occupation. Of the three patients with a poor result, one demonstrated slight winging on follow-up. Two of these patients had the only complications in the series. The other poor result was in a patient with concurrent cervical arthritis who had undergone a cervical spinal fusion before pectoralis muscle transfer. He did not have winging postoperatively but had decreased motion and moderate neck/shoulder pain. DISCUSSION Paralysis of the serratus anterior due to a long thoracic nerve lesion is infrequently encountered. Because of the length of the nerve and its relative vulnerability as it passes along the lateral chest wall,
it is susceptible to injury. This may occur during blunt trauma or during a surgical procedure on the superior thoracic region.15 The vast majority of traction injuries recover spontaneously over the course of several months. While awaiting recovery of the nerve, braces and splints have been used. However, patients often find them to be bulky and uncomfortable.14 Many patients have been reported to respond favorably to gentle shoulder exercises to maintain overall tone and range of motion, but it is difficult to differentiate the role of the exercise regimen from that of spontaneous evolution of the paresis. In those in whom clinical or electromyographic recovery fails to be demonstrated by 6 to 12 months, neurotization of the long thoracic nerve with use of intercostal nerves or the thoraco-dorsal nerve is technically possible, although there is only one report of this method in the literature at present.18 In patients who are seen 1 year or more after onset of paralysis, neurotization or nerve grafting procedures have not been as successful.9,17,26 However, in these patients muscle transfer may be beneficial. Many different muscle transfer procedures have been described, including use of the pectoralis minor2,24,29 and rhomboid major.10 The first author to describe the use of the pectoralis major was Tubby27 in 1904. In his description the pectoralis major is transferred directly onto the serratus anterior. Although Tubby reported successful results, subsequent authors recommended direct transfer to the scapula in order to provide a more secure fixation site. Dickson4 was one of the first to describe fascia lata transplantation from the lower border of the scapula to the pectoralis major; however, he did not detach the pectoralis insertion from the humerus. Durman5 developed a technique of detachment of the lower third of the pectoralis major insertion with fascia lata extension to the inferior pole of the scapula. He used this technique in two patients,
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Table IV Range-of-motion Isotrak data (percentage of motion of unaffected shoulder) Patient No. 2 3 4 5 6 Mean
Shoulder score index (ASES)
Forward elevation
External rotation
Touch opposite shoulder
Touch Top of head
Sacrum
Waist*
87 72 48 52 78 67.4
88 100 53 83 100 84
88 55 38 61 79 64
NS 129 63 90 95 97
NS 108 85 97 96 97
NS 90 75 145 92 100
NS 131 92 119 132 100
Eye*
Above head*
Above head with 2 kg weight*
NS 95 88 98 94 93
NS 100 81 112 94 96
NS 106 57 78 98 85
ASES, American Shoulder and Elbow Surgeons; NS, not sufficient data. *Lifting pitcher to specified level while standing.
as did Ober19 in a similar report. In 1963 Marmor and Bechtol16 described transfer of the entire pectoralis major with a successful result in one patient. Iceton and Harris13 reported on 13 men and 2 women treated with transfer of the sternal portion of the pectoralis major. Nine patients were judged to have a successful result with postoperative absence of winging and pain, but there was persistent minor weakness of shoulder adduction. Four patients in their series were thought to have either rupture or stretching of the fascia lata graft with recurrence of winging. Two of these responded well to insertion of the fascia lata graft. Post23 reported the results of transfer of the sternal portion of the pectoralis major muscle in 8 patients. Seven had no pain and achieved full motion at a mean postoperative follow-up period of 27 months. Three had decreased muscle endurance, but strength was reported as normal in all. In this same series, 4 patients who were judged to have concurrent multidirectional instability of the shoulder were relieved of their instability symptoms. Connor et al3 reported on 11 patients undergoing transfer of the sternal portion of the pectoralis major to the scapula with the use of autogenous fascia lata. Of 11 patients, 10 (91%) had satisfactory improvement in function and reduction of pain. One patient had recurrence of winging with acute failure of the transfer during physical therapy. Two of the manual laborers in this group (50%) required reassignment to lighter duty. Of the 11 patients, 3 had mild asymptomatic winging. Perlmutter and Leffert22 reported on 16 patients undergoing transfer of the entire pectoralis major to the scapula. Eight patients had an excellent result and five a good result. There were two postoperative graft failures, both related to physical activity and use of a fascia lata graft. The authors advised against the use of a single-layer strip of fascia and instead recommended the use of a rolled tubular graft for greater strength. Warner and Navarro30 described the results of 8 patients who underwent reconstruction with the use of the sternal portion of the pectoralis major and autog-
enous semitendinosus/gracilis tendon augmentation. In their series 7 of 8 patients had resolution of winging and improved function. Of note, their report was the first to describe use of the hamstring tendon as graft material. In addition, some of their patients had significant shoulder instability symptoms that were improved by transfer surgery, a result also noted by Post.23 In the present study, in the patients undergoing biomechanical examination, strength was found to be less on the operative side, with adduction recording the lowest values. Other studies on pectoralis major transfer have not evaluated objective strength measurements. Subjective loss of adduction strength was similarly noted by Iceton and Harris13 in all of their successful results and by Post.23 Range-of-motion testing by the 3-space Isotrak system also showed some decrease in both external rotation and forward elevation. The shoulder score index average of 67.4 might suggest that the overall outcome might be recorded as cautiously optimistic. This is similar to the average shoulder index score of 71 reported by Connor et al.3 Failure can occur after pectoralis major transfer and has been documented in multiple reports.3,13,22 In some instances this has been attributed to early aggressive physical therapy with resultant tearing or stretching of the fascia lata graft. Two methods have been suggested to help avoid the complication, both of which we would also advocate. First, a multilayered rolled fascia lata graft should be used and should be reinforced with nonabsorbable sutures throughout its length. Post23 performed the same technique and had no acute failures in his series, as was true in the present series. Second, an attempt should be made to achieve direct contact of the stump of the pectoralis major tendon with the scapula. This allows for the possibility of direct tendon healing with a minimal amount of intercalary avascular fascia lata graft. Because of the risk of avulsion of the pectoralis major transfer, we agree with others that a return to heavy lifting or manual labor should be prohibited for 4 to 6 months postoperatively.3,23 The results of this series are similar to those of other
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series. The majority of patients had significant improvement in their winging, with only 3 of 9 patients having slight winging. In the series of Connor et al,3 3 of 10 patients had slight winging, with 2 requiring work modifications. In our series 2 patients were unable to return to work. Overall, this series agrees with prior reports that pectoralis major transfer can be successful in relieving pain and shoulder girdle muscle fatigue in patients with serratus anterior paralysis. The majority of patients continue to perform shoulder-dependent activities of daily living at a reasonably normal level, although objective strength and range of motion measurements demonstrate a continued mild weakness and loss of motion as compared with the unaffected side.25 REFERENCES
1. Cahalan TD, Johnson ME, Chao EYS. Shoulder strength analysis using the Cybex II isokinetic dynamometer. Clin Orthop 1991; 27:249-57. 2. Chaves JP. Pectoralis minor transplant for paralysis of the serratus anterior. J Bone Joint Surg Br 1951;33:228-30. 3. Connor PM, Yamaguchi K, Manifold SG, et al. Split pectoralis major transfer for serratus anterior palsy. Clin Orthop 1997;341: 134-42. 4. Dickson FD. Fascial transplants in paralytic and other conditions. J Bone Joint Surg 1945;19:405-12. 5. Durman DC. An operation for paralysis of the serratus anterior. J Bone Joint Surg 1945;27:380-2. 6. Foo CL, Swann M. Isolated paralysis of the serratus anterior: a report of 20 cases. J Bone Joint Surg Br 1983;65:552-6. 7. Gozna ER, Harris WR. Traumatic winging of the scapula. J Bone Joint Surg Am 1979;61:1230-3. 8. Gregg JR, Labosky D, Harty M. Serratus anterior paralysis in the young athlete. J Bone Joint Surg Am 1979;61:825-31. 9. Gu YD, Chen DS, Zhang GM, et al. Long term functional results of contralateral C7 transfer. J Reconstr Microsurg 1998;14:57-9. 10. Herzmark MH. Traumatic paralysis of the serratus anterior relieved by transplantation of the rhomboids. J Bone Joint Surg 1951;33:235-8. 11. Horwitz MT, Tocantins LM. Anatomical study of the role of the long thoracic nerve and the related scapular bursa in the pathogenesis of the local paralysis of the serratus anterior muscle. Anat Rec 1938;71:375-85.
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12. Horwitz MT, Tocantins LM. Isolated paralysis of the serratus anterior (magnus) muscle. J Bone Joint Surg 1938;20:720-5. 13. Iceton J, Harris WR. Results of pectoralis major transfer for winged scapular. J Bone Joint Surg Br 1987;69:108-10. 14. Johnson JT, Kendall HO. Isolated paralysis of the serratus anterior muscle. J Bone Joint Surg Am 1955;37:567-74. 15. Kauppila LI, Vastamaki M. Iatrogenic serratus anterior paralysis: long-term outcome in 26 patients. Chest 1996;109:31-4. 16. Marmor L, Bechtol CO. Paralysis of the serratus anterior due to electrical shock relieved by transplantation of the pectoralis major muscle: a case report. J Bone Joint Surg Am 1963;45:156-60. 17. Mikami Y, Nagano A, Ochiai N, Yamamoto S. Results of nerve grafting for injuries of the axillary and suprascapular nerves [published erratum appears in J Bone Joint Surg Br 1997;79: 1045]. J Bone Joint Surg Br 1997;79:527-31. 18. Novak CB, Mackinnon SE. Surgical treatment of a long thoracic nerve palsy. Ann Thorac Surg 2002;73:1643-5. 19. Ober FR. Transplantation to improve the function of the shoulder joint and extensor function of the elbow joint. Instructional Course Lectures 1944;2:274-6. 20. O’Neil OR, Morrey BF, Tanaku S, An KN. Compensatory motion in the upper extremity after elbow arthrodesis. Clin Orthop 1992; 281:89-96. 21. Parsonage MJ, Turner JW. Neurologic amyotrophy. The shoulder girdle syndrome. Lancet 1948;1:973-8. 22. Perlmutter GS, Leffert RD. Results of transfer of the pectoralis major tendon to treat paralysis of the serratus anterior muscle. J Bone Joint Surg Am 1999;81:377-84. 23. Post M. Pectoralis major transfer for winging of the scapula. J Shoulder Elbow Surg 1995;4:1-9. 24. Rapp IH. Serratus anterior paralysis treated by transplant of the pectoralis minor. J Bone Joint Surg Am 1954;36:852-4. 25. Richards RR, An K-N, Bigliani LU, et al. A standardized method for the assessment of shoulder function. J Shoulder Elbow Surg 1994;3:347-52. 26. Songcharoen P, Mahaisavariya B, Chotigavanich S. Spinal accessory neurotization for restoration of elbow flexion in avulsion injuries of the brachial plexus. J Hand Surg [Am] 1996;21:38790. 27. Tubby AH. A case illustrating the operative treatment of paralysis of the serratus magnus by muscle grafting. BMJ 1904;2:1159-60. 28. Vastamaki M, Kauppila LI. Etiologic factors in isolated paralysis of the serratus anterior muscle. A report of 197 cases. J Shoulder Elbow Surg 1993;2:240-3. 29. Vastamaki M. Pectoralis minor transfer in serratus anterior paralysis. Acta Orthop Scand 1984;55:293-5. 30. Warner JP, Navarro RA. Serratus anterior dysfunction. Clin Orthop 1998;349:139-48.
Serratus anterior paralysis can result in winging of the scapula and weakness of arm elevation. The etiology of the condition is injury to the long thoracic nerve. There are many proposed causes of long thoracic nerve injury including acute trauma, Parsonage-Turner syndrome, or viral illness. The long length of the long thoracic nerve makes it prone to compression injury along the chest wall. Most patients recover nerve function with conservative treatment. In those in whom nerve function fails to recover, surgical treatment involving pectoralis major transfer may be beneficial. In this study 9 patients underwent pectoralis major transfer with a fascia lata extension graft. The symptoms of most were improved, with correction of the winging and improved movement in the affected shoulder. (J Shoulder Elbow Surg 2003;12:555-60.)
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aralysis of the serratus anterior muscle results in winging of the scapula with attempted arm elevation. This is best noticed when the patient is viewed from behind. Those with serratus anterior paralysis complain of pain in the shoulder, weakness of arm elevation, and shoulder girdle muscle fatigue. The etiology of the condition is injury to the long thoracic nerve, which is the sole innervation of the serratus anterior. The long thoracic nerve is formed primarily from contributions of nerve roots C5 and C6 with additional innervation from C7.11,12 There are many described causes of a long thoracic nerve lesion including acute trauma, repetitive trauma, surgical positioning, viral illness, and Parsonage-Turner syndrome or paralytic brachial neuritis.6,8,14,15,21,28 Excluding penetrating trauma, a traction or compression mechanism of injury is assumed in many cases to account for damage to the long thoracic nerve. Several investigators have performed dissections to determine where the nerve may be prone to impingement or compression injury. From Orthopaedic Surgery, Mayo Medical School,a and Hand and Microsurgery, Department of Orthopaedics, Mayo Clinic.b Reprint requests: Scott P. Steinmann, MD, Mayo Clinic, 200 First Street SW, Rochester, MN 55905. (E-mail: steinmann.scott @mayo.edu). Copyright © 2003 by Journal of Shoulder and Elbow Surgery Board of Trustees. 1058-2746/2003/$35.00 ⫹ 0 doi:10.1016/S1058-2746(03)00174-5
Some believe the nerve is vulnerable to traction or compression as it crosses the second rib7,11 or compression as it passes through the middle scalene muscle. Other theories include traction to the nerve as the head is rotated and laterally tilted away from the shoulder8 or compression at the anterior inferior border of the scapula.16 In addition, the considerable length of the nerve, measuring approximately 20 cm,16 and its superficial location along the lateral chest from the eighth to the ninth rib increase its vulnerability. The vast majority of those with closed injury recover spontaneously over the course of several months with conservative treatment.14 By 6 to 12 months, most have recovered. Occasionally, patients are seen who do not have clinical improvement with extended conservative treatment of greater than 1 year. Electromyographic studies can be used to detect any subclinical recovery of the muscle during this waiting period. When no recovery has been documented after prolonged conservative treatment, surgical reconstruction can be considered. This study examines the clinical results in a consecutive series of patients undergoing pectoralis major transfer to the vertebral border of the scapula. MATERIALS AND METHODS Nine patients with the diagnosis of serratus anterior paralysis were identified through a computerized search of our institutional database. Exclusion criteria included a follow-up period of less than 1 year or lack of preoperative electromyographic documentation of complete serratus anterior denervation. The evaluation proposal was approved by the Institutional Review Board. All patients were evaluated by an impartial observer (S.P.S.) not involved with their direct care by review of the last clinic note and patients’ responses to a questionnaire and personal examination. Evaluations included shoulder range of motion, pain, presence or absence of scapular winging, shoulder strength, presence of complications, and work status. Winging was identified if, upon inspection and observation from behind the patient, visible protrusion of the scapula occurred with the initiation of forward arm elevation. At final follow-up, those patients returning were invited to undergo biomechanical testing in our biomechanics laboratory. Five of nine patients agreed to further evaluation. Biomechanical testing included Cybex II strength testing (Lumex, Ronkonkoma, NY). Isometric strength was measured in adduction, abduction, external rotation, and inter-
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nal rotation. Results were expressed as a percentage of the unaffected shoulder.1 In addition, in these 5 patients, range of motion was measured by the 3-space Isotrak system (Polhemus Navigation Sciences Division, Colchester, VT). This system allows real-time monitoring of complex shoulder motion. The device is based on the electromagnetic tracking concept in which a set of magnetic sensors are placed on the patient’s trunk, shoulders, and arms. As motion is initiated, range of motion of the upper extremity is continually recorded.20 In addition to standard shoulder motion parameters of forward elevation, external rotation, and internal rotation, these 5 patients were asked to perform a series of activities of daily living requiring progressively greater shoulder work. These included reaching the opposite shoulder, touching the top of the head and sacrum, and lifting a pitcher to waist height, eye height, and just above head height while standing. Results were expressed as a percentage of the unaffected shoulder. The 5 patients undergoing biomechanical testing were also evaluated with the American Shoulder and Elbow Surgeons patient self-evaluation form.25 There were 5 men and 4 women with a mean age of 33.6 years (range, 21-47 years). The duration of symptoms averaged 34 months (range, 24-60 months). Serratus anterior palsy was a result of acute trauma in 5 cases, minor trauma in 2 cases, and iatrogenic injury during thoracic surgery in 2 patients. Of 9 patients, 5 had preinjury occupations requiring heavy labor whereas 4 patients did office work. Two had undergone previous surgery including carpal tunnel release and cervical spinal fusion. All had complained preoperatively of chronic pain and early fatigue in the shoulder with arm elevation during daily activities.
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Figure 1 Anterior view of shoulder axilla. The white arrow demonstrates the pectoralis major detached from the humerus, ready for attachment to a fascia lata graft.
Surgical technique The operation involved detachment of the pectoralis major from the humerus and reattachment at the junction of the middle and distal third of the lateral scapula with a fascia lata extension graft. The patient was placed in the lateral decubitus position with the use of a standard axillary roll pad, with the head of the table elevated 15° to 20°. Early in the series, an incision was made in the axilla over the palpable lateral margin of the pectoralis major, which was curved across the axilla to the inferior pole of the scapula. Later, a limited technique was used involving a 4-cm axillary incision and a second incision parallel to the scapular inferior vertebral border approximately 5 cm in length. The pectoralis major was detached from the humerus (Figure 1). A portion of fascia lata, measuring approximately 5 ⫻ 15 cm, was then harvested from the thigh via a longitudinal incision. (Harvest of the fascia lata may be performed by a second surgical team while the pectoralis major is dissected.) This was rolled upon itself and two No. 5 braided nonabsorbable sutures placed in a running fashion throughout the length of the graft. One end of the graft was then sutured to the tendon stump of the pectoralis major. A 1-cm-wide hole was made with a burr on the inferior pole of the scapula at the junction of the middle and distal third. The fascia lata graft was placed through the hole and sutured back upon itself while the stump of the pectoralis major tendon was pulled to the edge of the scapula (Figures 2, 3, and 4). The tendon of the pectoralis
Figure 2 Anterior view. The pectoralis major has been detached from the humerus and attached to the inferior scapula with a fascia lata graft.
major contacted the scapula. Ideally, the fascia lata was used to augment the pectoralis major tendon and not to act as an extension. If used as an extension, the avascular fascia lata may over time be at risk for elongation or rupture. When the sutures were being tied, the scapula was held firmly anteriorly because the graft tended to stretch slightly over time. After standard surgical closure and drainage, the arm was placed into a Velpeau sling and immobilized for 6 weeks. For 5 of the patients in this series, the arm was initially placed into a shoulder spica cast in neutral rotation. During the postoperative period, only gentle pendulum exercises were performed. At 6 weeks postoperatively, the cast or sling was removed and progressive active and passive exercises to the shoulder girdle initiated. At 12
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Table I Definition of excellent, good, and poor results Excellent: ROM within 90% of unaffected side No winging No pain Strength 5/5 Good: ROM withing 75%-90% of unaffected side Slight winging Mild pain Moderate weakness 4/5 Poor: ROM ⬍75% of unaffected side Persistent winging Moderate or severe pain Strength 3/5 ROM, Range of motion.
Figure 3 Posterior view. The pectoralis major has been passed posteriorly and connected to the scapula with a fascia lata graft. The native tendon of the pectoralis major will typically abut the edge of the scapula.
Figure 4 Patient in lateral decubitus position. The black arrow demonstrates the anterior axillary incision; the white arrow demonstrates the incision over the inferior scapula. A fascia lata graft is passed from anterior to posterior incision.
weeks postoperatively, return to noncontact athletic activities was permitted. At 6 months, resumption of heavy lifting or work was allowed.
RESULTS At final follow-up, patients’ results were graded as either excellent, good, or poor (Table I). A patient with an excellent result had total range of motion within 90% of the unaffected side, no visible scapular winging, no pain, and normal strength. A patient with a good result had range of motion between 75% to 90% of the unaffected side, minimal winging, mild
pain, and minimal weakness. A patient with a poor result had range of motion of less than 75% of the unaffected side, winging unchanged from preoperatively, severe pain, and significantly less strength than the unaffected side. Follow-up averaged 70 months (range, 12-168 months) (Table II). Preoperatively, the patients averaged 90° forward elevation with 4/5 weakness on muscle strength testing and 50° external rotation. Postoperatively, the nine patients were noted to have mean forward elevation of 144° (range, 53°-165°) and 52° external rotation (range, 25°-88°). Five patients had no pain, two patients had slight pain, and two patients had moderate pain. None had severe pain. Postoperatively, four patients had normal strength and five were graded 4/5. Postoperatively, there were three complications in two patients (patients 5 and 9). In both adhesive capsulitis developed in the immediate postoperative period. One (patient 9) also required drainage of a thigh seroma after fascia lata grafting. Both patients had been treated in a shoulder spica cast. Apparent resolution of winging occurred in six patients. Three had slight winging. Of the seven who were employed outside the home, five were able to return to work but two were unable to return to work because of pain and poor function. Isometric strength evaluation in the five patients undergoing biomechanical testing is presented in Table III. Mean isometric strength of adduction was lowest at 59% of the unaffected side, followed by external rotation rated at 62%, abduction 68%, and internal rotation 73%. Overall, two of these patients were rated as excellent, one as good, and two as poor. Three-space Isotrak measurements of humeral elevation during specified activities of daily living revealed the greatest difference in external rotation (mean, 64% of unaffected side) and with forward
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Table II Patient characteristics Duration of symptoms Patient Age (mos) No. (y) Sex Side
Cause
Return to ElectroFollow-up Final myography Occupation (mo) Result Winging work Complications
1
32
M
R
30
Fall
⫹
2 3 4 5
23 47 39 44
F F M F
R R R R
36 60 24 24
6 7 8 9
37 21 26 47
M F M M
R R R R
24 48 36 24
Throwing Seizure Iatrogenic Motor vehicle accident Fall Iatrogenic Heavy lifting Crush injury
48
Excellent
None
Yes
No
⫹ ⫹ ⫹ ⫹
Manual laborer Waitress Housewife Repairman Cook
168 132 48 12
Excellent Good Poor Poor
None Slight None Slight
Yes Yes No Yes
⫹ ⫹ ⫹ ⫹
Repairman Singer Carpenter Carpenter
48 24 84 60
Excellent Good Excellent Poor
None Slight None None
Yes Yes Yes No
No No No Adhesive capsulitis No No No Thigh seroma/ adhesive capsulitis
Table III Isometric strength measurements (percentage of unaffected side) Patient No. 2 3 4 5 6
Abduction
Adduction
External rotation
Internal rotation
53 100 61 45 79
58 73 68 42 52
64 100 42 25 80
64 100 67 58 76
elevation of the arm (84% of unaffected side) (Table IV). The other activities were less demanding and ranged from 85% to 100% of the unaffected side. The American Shoulder and Elbow Surgeons shoulder index score averaged 67.4 out of a possible 100. Overall, there were four excellent, two good, and three poor results. Those with excellent results included three manual laborers with a mean follow-up of 87 months (range, 24-168 months). The two patients with a good result both had slight winging at follow-up (132 months and 24 months, respectively) but had returned to their previous occupation. Of the three patients with a poor result, one demonstrated slight winging on follow-up. Two of these patients had the only complications in the series. The other poor result was in a patient with concurrent cervical arthritis who had undergone a cervical spinal fusion before pectoralis muscle transfer. He did not have winging postoperatively but had decreased motion and moderate neck/shoulder pain. DISCUSSION Paralysis of the serratus anterior due to a long thoracic nerve lesion is infrequently encountered. Because of the length of the nerve and its relative vulnerability as it passes along the lateral chest wall,
it is susceptible to injury. This may occur during blunt trauma or during a surgical procedure on the superior thoracic region.15 The vast majority of traction injuries recover spontaneously over the course of several months. While awaiting recovery of the nerve, braces and splints have been used. However, patients often find them to be bulky and uncomfortable.14 Many patients have been reported to respond favorably to gentle shoulder exercises to maintain overall tone and range of motion, but it is difficult to differentiate the role of the exercise regimen from that of spontaneous evolution of the paresis. In those in whom clinical or electromyographic recovery fails to be demonstrated by 6 to 12 months, neurotization of the long thoracic nerve with use of intercostal nerves or the thoraco-dorsal nerve is technically possible, although there is only one report of this method in the literature at present.18 In patients who are seen 1 year or more after onset of paralysis, neurotization or nerve grafting procedures have not been as successful.9,17,26 However, in these patients muscle transfer may be beneficial. Many different muscle transfer procedures have been described, including use of the pectoralis minor2,24,29 and rhomboid major.10 The first author to describe the use of the pectoralis major was Tubby27 in 1904. In his description the pectoralis major is transferred directly onto the serratus anterior. Although Tubby reported successful results, subsequent authors recommended direct transfer to the scapula in order to provide a more secure fixation site. Dickson4 was one of the first to describe fascia lata transplantation from the lower border of the scapula to the pectoralis major; however, he did not detach the pectoralis insertion from the humerus. Durman5 developed a technique of detachment of the lower third of the pectoralis major insertion with fascia lata extension to the inferior pole of the scapula. He used this technique in two patients,
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Table IV Range-of-motion Isotrak data (percentage of motion of unaffected shoulder) Patient No. 2 3 4 5 6 Mean
Shoulder score index (ASES)
Forward elevation
External rotation
Touch opposite shoulder
Touch Top of head
Sacrum
Waist*
87 72 48 52 78 67.4
88 100 53 83 100 84
88 55 38 61 79 64
NS 129 63 90 95 97
NS 108 85 97 96 97
NS 90 75 145 92 100
NS 131 92 119 132 100
Eye*
Above head*
Above head with 2 kg weight*
NS 95 88 98 94 93
NS 100 81 112 94 96
NS 106 57 78 98 85
ASES, American Shoulder and Elbow Surgeons; NS, not sufficient data. *Lifting pitcher to specified level while standing.
as did Ober19 in a similar report. In 1963 Marmor and Bechtol16 described transfer of the entire pectoralis major with a successful result in one patient. Iceton and Harris13 reported on 13 men and 2 women treated with transfer of the sternal portion of the pectoralis major. Nine patients were judged to have a successful result with postoperative absence of winging and pain, but there was persistent minor weakness of shoulder adduction. Four patients in their series were thought to have either rupture or stretching of the fascia lata graft with recurrence of winging. Two of these responded well to insertion of the fascia lata graft. Post23 reported the results of transfer of the sternal portion of the pectoralis major muscle in 8 patients. Seven had no pain and achieved full motion at a mean postoperative follow-up period of 27 months. Three had decreased muscle endurance, but strength was reported as normal in all. In this same series, 4 patients who were judged to have concurrent multidirectional instability of the shoulder were relieved of their instability symptoms. Connor et al3 reported on 11 patients undergoing transfer of the sternal portion of the pectoralis major to the scapula with the use of autogenous fascia lata. Of 11 patients, 10 (91%) had satisfactory improvement in function and reduction of pain. One patient had recurrence of winging with acute failure of the transfer during physical therapy. Two of the manual laborers in this group (50%) required reassignment to lighter duty. Of the 11 patients, 3 had mild asymptomatic winging. Perlmutter and Leffert22 reported on 16 patients undergoing transfer of the entire pectoralis major to the scapula. Eight patients had an excellent result and five a good result. There were two postoperative graft failures, both related to physical activity and use of a fascia lata graft. The authors advised against the use of a single-layer strip of fascia and instead recommended the use of a rolled tubular graft for greater strength. Warner and Navarro30 described the results of 8 patients who underwent reconstruction with the use of the sternal portion of the pectoralis major and autog-
enous semitendinosus/gracilis tendon augmentation. In their series 7 of 8 patients had resolution of winging and improved function. Of note, their report was the first to describe use of the hamstring tendon as graft material. In addition, some of their patients had significant shoulder instability symptoms that were improved by transfer surgery, a result also noted by Post.23 In the present study, in the patients undergoing biomechanical examination, strength was found to be less on the operative side, with adduction recording the lowest values. Other studies on pectoralis major transfer have not evaluated objective strength measurements. Subjective loss of adduction strength was similarly noted by Iceton and Harris13 in all of their successful results and by Post.23 Range-of-motion testing by the 3-space Isotrak system also showed some decrease in both external rotation and forward elevation. The shoulder score index average of 67.4 might suggest that the overall outcome might be recorded as cautiously optimistic. This is similar to the average shoulder index score of 71 reported by Connor et al.3 Failure can occur after pectoralis major transfer and has been documented in multiple reports.3,13,22 In some instances this has been attributed to early aggressive physical therapy with resultant tearing or stretching of the fascia lata graft. Two methods have been suggested to help avoid the complication, both of which we would also advocate. First, a multilayered rolled fascia lata graft should be used and should be reinforced with nonabsorbable sutures throughout its length. Post23 performed the same technique and had no acute failures in his series, as was true in the present series. Second, an attempt should be made to achieve direct contact of the stump of the pectoralis major tendon with the scapula. This allows for the possibility of direct tendon healing with a minimal amount of intercalary avascular fascia lata graft. Because of the risk of avulsion of the pectoralis major transfer, we agree with others that a return to heavy lifting or manual labor should be prohibited for 4 to 6 months postoperatively.3,23 The results of this series are similar to those of other
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series. The majority of patients had significant improvement in their winging, with only 3 of 9 patients having slight winging. In the series of Connor et al,3 3 of 10 patients had slight winging, with 2 requiring work modifications. In our series 2 patients were unable to return to work. Overall, this series agrees with prior reports that pectoralis major transfer can be successful in relieving pain and shoulder girdle muscle fatigue in patients with serratus anterior paralysis. The majority of patients continue to perform shoulder-dependent activities of daily living at a reasonably normal level, although objective strength and range of motion measurements demonstrate a continued mild weakness and loss of motion as compared with the unaffected side.25 REFERENCES
1. Cahalan TD, Johnson ME, Chao EYS. Shoulder strength analysis using the Cybex II isokinetic dynamometer. Clin Orthop 1991; 27:249-57. 2. Chaves JP. Pectoralis minor transplant for paralysis of the serratus anterior. J Bone Joint Surg Br 1951;33:228-30. 3. Connor PM, Yamaguchi K, Manifold SG, et al. Split pectoralis major transfer for serratus anterior palsy. Clin Orthop 1997;341: 134-42. 4. Dickson FD. Fascial transplants in paralytic and other conditions. J Bone Joint Surg 1945;19:405-12. 5. Durman DC. An operation for paralysis of the serratus anterior. J Bone Joint Surg 1945;27:380-2. 6. Foo CL, Swann M. Isolated paralysis of the serratus anterior: a report of 20 cases. J Bone Joint Surg Br 1983;65:552-6. 7. Gozna ER, Harris WR. Traumatic winging of the scapula. J Bone Joint Surg Am 1979;61:1230-3. 8. Gregg JR, Labosky D, Harty M. Serratus anterior paralysis in the young athlete. J Bone Joint Surg Am 1979;61:825-31. 9. Gu YD, Chen DS, Zhang GM, et al. Long term functional results of contralateral C7 transfer. J Reconstr Microsurg 1998;14:57-9. 10. Herzmark MH. Traumatic paralysis of the serratus anterior relieved by transplantation of the rhomboids. J Bone Joint Surg 1951;33:235-8. 11. Horwitz MT, Tocantins LM. Anatomical study of the role of the long thoracic nerve and the related scapular bursa in the pathogenesis of the local paralysis of the serratus anterior muscle. Anat Rec 1938;71:375-85.
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12. Horwitz MT, Tocantins LM. Isolated paralysis of the serratus anterior (magnus) muscle. J Bone Joint Surg 1938;20:720-5. 13. Iceton J, Harris WR. Results of pectoralis major transfer for winged scapular. J Bone Joint Surg Br 1987;69:108-10. 14. Johnson JT, Kendall HO. Isolated paralysis of the serratus anterior muscle. J Bone Joint Surg Am 1955;37:567-74. 15. Kauppila LI, Vastamaki M. Iatrogenic serratus anterior paralysis: long-term outcome in 26 patients. Chest 1996;109:31-4. 16. Marmor L, Bechtol CO. Paralysis of the serratus anterior due to electrical shock relieved by transplantation of the pectoralis major muscle: a case report. J Bone Joint Surg Am 1963;45:156-60. 17. Mikami Y, Nagano A, Ochiai N, Yamamoto S. Results of nerve grafting for injuries of the axillary and suprascapular nerves [published erratum appears in J Bone Joint Surg Br 1997;79: 1045]. J Bone Joint Surg Br 1997;79:527-31. 18. Novak CB, Mackinnon SE. Surgical treatment of a long thoracic nerve palsy. Ann Thorac Surg 2002;73:1643-5. 19. Ober FR. Transplantation to improve the function of the shoulder joint and extensor function of the elbow joint. Instructional Course Lectures 1944;2:274-6. 20. O’Neil OR, Morrey BF, Tanaku S, An KN. Compensatory motion in the upper extremity after elbow arthrodesis. Clin Orthop 1992; 281:89-96. 21. Parsonage MJ, Turner JW. Neurologic amyotrophy. The shoulder girdle syndrome. Lancet 1948;1:973-8. 22. Perlmutter GS, Leffert RD. Results of transfer of the pectoralis major tendon to treat paralysis of the serratus anterior muscle. J Bone Joint Surg Am 1999;81:377-84. 23. Post M. Pectoralis major transfer for winging of the scapula. J Shoulder Elbow Surg 1995;4:1-9. 24. Rapp IH. Serratus anterior paralysis treated by transplant of the pectoralis minor. J Bone Joint Surg Am 1954;36:852-4. 25. Richards RR, An K-N, Bigliani LU, et al. A standardized method for the assessment of shoulder function. J Shoulder Elbow Surg 1994;3:347-52. 26. Songcharoen P, Mahaisavariya B, Chotigavanich S. Spinal accessory neurotization for restoration of elbow flexion in avulsion injuries of the brachial plexus. J Hand Surg [Am] 1996;21:38790. 27. Tubby AH. A case illustrating the operative treatment of paralysis of the serratus magnus by muscle grafting. BMJ 1904;2:1159-60. 28. Vastamaki M, Kauppila LI. Etiologic factors in isolated paralysis of the serratus anterior muscle. A report of 197 cases. J Shoulder Elbow Surg 1993;2:240-3. 29. Vastamaki M. Pectoralis minor transfer in serratus anterior paralysis. Acta Orthop Scand 1984;55:293-5. 30. Warner JP, Navarro RA. Serratus anterior dysfunction. Clin Orthop 1998;349:139-48.