- Email: [email protected]
Delayed onset of posterior interosseous nerve palsy after a nonanatomic routing of a distal biceps repair: A case report
J Shoulder Elbow Surg (2010) 19, e1-e5
www.elsevier.com/locate/ymse
CASE REPORTS
Delayed onset of posterior interosseous nerve palsy after a nonanatomic routing of a distal biceps repair: A case report Kristofer S. Matullo, MD, Nicholas L. Strasser, MD, Allen T. Bishop, MD, Alexander Y. Shin, MD, Bassem T. Elhassan, MD* Mayo Clinic, Rochester, MN Rupture of the distal biceps tendon is an uncommon injury.7,15 Conservative management of distal biceps ruptures has been reported to lead to a loss of power and endurance in elbow flexion and forearm supination.1,15 Surgical repair using a single- or double-incision technique has been recommended by most authors to restore elbow flexion and supination strength, especially in young active patients.18 Injury to the posterior interosseous nerve (PIN) has been reported to be more common with the singleincision technique, whereas heterotopic ossification and synostosis of the proximal radioulnar joint has been reported to be more common with the double-incision technique.2,3,5,6,8,11 Cases have also been reported of tendon rerupture, reflex sympathetic dystrophy, and neurologic injury, including the median nerve, superficial sensory branch of the radial nerve, lateral antebrachial cutaneous nerve, and anterior interosseous nerve, as well as temporary and permanent deficits of the PIN.3,5,6,10-12,17 We present a very rare complication of a distal biceps tendon repair performed through the double-incision technique. The tendon was fixed to the radial tuberosity but was routed laterally to the radius, with resultant radial nerve compression and delayed PIN palsy. To our knowledge, this complication has not been reported previously in the literature. The patient was informed of and agreed to publishing his case. *Reprint requests: Bassem T. Elhassan, MD, The Mayo Clinic, Gonda 14, Rochester, MN 55905. E-mail address: [email protected] (B.T. Elhassan).
Case report A 48-year-old farmer presented to our institution with symptoms of loss of forearm supination and weakness of thumb, finger, and wrist extension in his dominant right arm. He had sustained a distal biceps tendon rupture 18 months earlier after lifting a heavy object that was treated elsewhere with a 2-incision repair.4 His examination before the surgical repair demonstrated significant weakness in flexion and supination but showed he was otherwise neurologically intact. After surgery, the patient was placed in a long arm cast with his elbow in 90 of flexion for 3 weeks, followed by a hinged elbow brace with gradual extension for 3 weeks. He was started on active assisted range of motion exercises beginning 6 weeks after surgery. During his rehabilitation, he was not able to actively supinate his forearm with the elbow flexed despite extensive physical therapy. This problem was further complicated by progressive extension weakness of the wrist, thumb, and fingers, which started almost 10 months after his tendon repair. He was referred to us for further evaluation of the progressive hand weakness. The examination showed the previous surgical wounds appeared well healed, with no overlying skin changes or tenderness to palpation. His active elbow motion demonstrated a 135 arc of flexion from full extension to 135 of flexion. Active forearm pronation was 65 . Supination was very limited when the elbow was actively flexed to 90 but improved to 30 with the elbow extended. The most striking finding was the
1058-2746/$ - see front matter Ó 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. doi:10.1016/j.jse.2009.11.054
e2
K.S. Matullo et al.
Figure 1 (A-D) Magnetic resonance imaging demonstrates the biceps tendon ()) traveling around the lateral side of the radius to insert on the bicipital tuberosity (arrow).
observation of obligate forearm pronation during active elbow flexion. When the elbow was passively flexed, however, concomitant forearm pronation was not present. His passive elbow and forearm motions were similar to the contralateral side except for a 10 loss of passive supination of the injured side (70 ) compared with the contralateral side (80 ). Examination of the hand and wrist demonstrated full passive range of motion, but the patient lacked active extension of his fingers at the level of the metacarpophalangeal joints. He had full extension of his wrist into radial deviation but could not maintain straight or ulnarly deviated wrist extension. Strength testing was grade 5 in the triceps and biceps, grade 4 of the extensor carpi radialis longus and extensor carpi radialis brevis, grade 3 of the extensor carpi ulnaris, grade 2 of the supinator, grade 1 of the extensor digitorum communis, and grade 0 of the extensor digiti quinti, extensor indices proprius, and extensor pollicis longus. Sensory examination showed intact sensation over the radial aspect of the wrist, dorsal aspect of the thumb, and in all fingers. These findings were consistent with a PIN palsy.
Radiographs of the right elbow demonstrated minimal heterotopic ossification at the level of the radial tuberosity. Electromyelographic evaluation was consistent with a PIN palsy without involvement of the superficial sensory branch of the radial nerve. Magnetic resonance imaging of the elbow and distal forearm showed evidence of a healed biceps tendon to the radial tuberosity; however, the biceps tendon appeared to be routed laterally rather than medially to the proximal radius at the level of the tuberosity (Fig. 1). Because of these findings, the patient underwent surgical exploration of the biceps tendon and PIN through the previous incisions. The posterior incision was extended, and after extensive scar release, it was evident that the biceps tendon was routed incorrectly around the lateral border of the radius between the PIN and the superficial sensory branch of the radial nerve (Figs. 2 and 3). Extensive scarring was also observed surrounding the proper radial nerve, the proximal radioulnar joint, and the PIN at the level of the malrouted biceps tendon and extending through the supinator muscle. The biceps tendon was released from its aberrant attachment and was delivered through the anterior wound. Release of the supinator and proximal radioulnar joint with
Biceps repair and PIN palsy
e3
Figure 3 Intraoperative photograph demonstrates the biceps tendon ()) passing superficially to the posterior interosseous nerve (white arrow) and deep to the superficial sensory branch of the radial nerve (black arrow).
hand function. He returned back to his preinjury work without restriction and was working out regularly without complaint.
Discussion
Figure 2 Intraoperative photograph demonstrates the biceps tendon passing around the lateral border of the radius.
concomitant neurolysis of the radial nerve and PIN was performed. Full passive supination was regained in the operating room. The biceps tendon was then correctly routed along the medial border of the radius and attached to the radial tuberosity using a trough and transosseous sutures. The patient was managed with a sling postoperatively, allowing active flexion of the elbow from 90 to full flexion for 4 weeks, followed by progressive extension of the elbow over a 2-week period. He was allowed full active flexionextension of the elbow, with active assisted range of motion for forearm rotation starting at 6 weeks. He was allowed unrestricted range of motion of the elbow and forearm at 3 months, with progressive strengthening at 4 months. At 7 months postoperatively, the patient had full range of motion of the elbow joint, forearm pronation of 70 , and supination of 50 , regardless of the elbow flexion angle. Strength testing of the biceps revealed 60 pounds on the left and right, and pronation was 40 pounds bilaterally; however, supination was limited to 20 pounds on the right compared with 40 pounds on the left. The patient regained full wrist extension and full finger extension with the wrist held in a neutral position. At 1 year after surgery, range of motion, flexion and pronation strength were maintained. Supination strength increased to 30 pounds. He subjectively rated his injured arm at 90% compared with the contralateral elbow and
Distal biceps tendon rupture is an uncommon injury that typically occurs when the forearm is rapidly extended against resistance, resulting in a rupture from the radial bicipital tuberosity.5,15,16 Surgical treatment is offered in an attempt to restore normal function to the elbow. Symptomatic management of these injuries without surgical fixation results in a decrease in endurance and a loss of supination strength by 40% and flexion strength by an average of 30%.1,15 Surgical biceps tenodesis to the brachialis is an option for the elderly or lower-demand patient that results in a decrease in supination strength of 50% but nearly normal flexion strength.15 Primary repair, however, helps to restore motion as well as flexion and supination strength and endurance to nearly normal values.18 Complications of biceps tendon repair are varied, but increase with a more prolonged time to surgical fixation.11 Boyd and Anderson4 described a 2-incision technique to help reduce the rate of neurologic complications, but there is a higher reported rate of heterotopic ossification compared with a single-incision repair, tenodesis, or conservative management.2,5,6,11 Complete synostosis of the proximal radioulnar joint has also occurred, preventing forearm pronosupination,3,8 and tendon rerupture and reflex sympathetic dystrophy have also been described. 3,6,11 Posterior interosseous nerve injury may result in decreased strength and inability to extend the fingers and thumb, as well as radial deviation with dorsal wrist extension due to the unopposed pull of the extensor carpi radialis longus tendon. The PIN has been reported to have a lower rate of injury with a double-incision approach than with the single Henry incision.4,9 Injury to the PIN can still occur with the double-incision technique, possibly due to traction
e4
K.S. Matullo et al.
Figure 4 An example of biceps tendon repair through double incision technique performed in a fresh cadaver elbow. Notice the proximity of the biceps tendon (red arrow) to the PIN (black arrow) and superficial branch of the radial nerve (black circle).
Figure 5 Recreation of the complication reported in this manuscript using a fresh frozen cadaver elbow. Notice how the aberrant passage of the biceps tendon laterally may pass between the two main branches of the radial nerve at the elbow and potentially compresses the PIN.
or aberrant retractor placement during the posterior exposure and attachment of the tendon to the tuberosity.14 Position of the forearm during biceps repair is also an important factor in nerve injury. Although it is commonly reported that positioning the forearm in pronation protects the PIN during biceps repair through the posterolateral approach, a recent report has suggested that the pronated position may lead to increased pressure on the nerve as it travels through the supinator.13 In addition, during biceps tendon repair using a single-incision technique, the forearm should be placed in supination to keep the nerve more lateral and away from the surgical repair site. Figure 4 shows an example of biceps tendon repair performed in a fresh frozen cadaveric elbow through the doubleincision technique. Notice how close the biceps tendon is to the PIN, which indicates that potential injury to this nerve is possible with either the single- or double-incision technique. Positioning of the forearm and excessive retraction of the soft tissues containing the nerve are the main potential risk factors for nerve injury. Typically, PIN injury is a temporary neurapraxia that resolves at average of 2 to 6 months after fixation;5,11 however, permanent damage has been reported.
To our knowledge, the case we are reporting here has not been reported previously. Routing the biceps tendon laterally around the proximal radius at the level of the tuberosity is a rare technical error that may occur with a surgeon’s unfamiliarity of elbow anatomy. This abnormal rerouting will likely always cause compression of the PIN unless the tendon is passed deep to the visualized nerve. In Figure 5 we tried to replicate the injury in a fresh frozen cadaveric elbow. Notice how the passage of the biceps tendon laterally may pass between the 2 main branches of the radial nerve at the elbow and leads to compression of the PIN. We believe that the progressive PIN palsy developed as a result of compression by the malrouted biceps tendon combined with the extensive scar accumulation. Previous delayed PIN neurapraxia has been described with a gradual decrease in PIN function occurring 4 months after repair.10 Exploration in this patient demonstrated scar formation of the proximal 2 cm of the PIN within the supinator muscle. There was a full recovery 4.5 months after neurolysis. The original loss of function in our patient developed more slowly, over 10 months, and he obtained recovery of PIN function during the next 7 months postoperatively.
Biceps repair and PIN palsy Although his elbow function significantly improved, forearm supination still lacked full motion and strength. This could be partly related to recurrence of local scarring and the supinator release performed to decompress the PIN.
Conclusion Delayed onset of PIN palsy, secondary to a routing error in the surgical insertion of the biceps tendon through the double-incision technique is a very rare complication of biceps tendon repair. During fixation of the tendon to the bicipital tuberosity, the tendon should be passed ulnarly and distally to radius neck. If the entire tendon is visualized or partially seen laterally as coursing from superior to inferior, the potential of malrouting should be considered. Aberrant routing may cause abnormal obligate forearm pronation with elbow flexion, neurapraxia due to scar formation, and direct PIN compression. Reversal of the abnormally routed tendon should be done as soon as it is recognized to improve the chance of recovery of elbow and forearm motion as well as PIN function.
Disclaimer The authors, their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.
References 1. Baker BE, Bierwagen D. Rupture of the distal tendon of the biceps brachii. Operative versus non-operative treatment. J Bone Joint Surg Am 1985;67:414-7. 2. Bell RH, Wiley WB, Noble JS, Kuczynski DJ. Repair of distal biceps brachii tendon ruptures. J Shoulder Elbow Surg 2000;9:223-6.
e5 3. Bisson L, Moyer M, Lanighan K, Marzo J. Complications associated with repair of a distal biceps rupture using the modified two-incision technique. J Shoulder Elbow Surg 2008;17(1 suppl. 1):S67-71. 4. Boyd HB, Anderson LD. A method for reinsertion of the distal biceps brachii tendon. J Bone Joint Surg Am 1961;43:1041-3. 5. Chillemi C, Marinelli M, De Cupis V. Rupture of the distal biceps brachii tendon: conservative treatment versus anatomic reinsertiondclinical and radiological evaluation after 2 years. Archives Orthop Trauma Surg 2007;127:705-8. 6. Cohen MS, Katolic L. Complications of distal biceps tendon repairs. Op Tech Sports Med 2003;11:60-6. 7. Davis WM, Yassine Z. An etiological factor in tear of the distal tendon of the biceps brachii; report of two cases. J Bone Joint Surg Am 1956;38:1365-8. 8. Failla F, Amadio PC, Morrey BF, Beckenbaugh RD. Proximal radioulnar synostosis after repair of distal biceps brachii rupture by the twoincision technique: report of four cases. Clin Orthop 1990;253:133-6. 9. Hovelius L, Josefsson G. Rupture of the distal biceps tendon. Report of five cases. Acta Orthop Scand 1977;48:280-2. 10. Katzman BM, Caligiuri DA, Klein DM, Gorup JM. Delayed onset of posterior interosseous nerve palsy after distal biceps tendon repair. J Shoulder Elbow Surg 1997;6:393-5. 11. Kelly EW, Morrey BF, O’Driscoll SW. Complications of repair of the distal biceps tendon with the modified two-incision technique. J Bone Joint Surg Am 2000;82:1575-81. 12. Lin KH, Leslie BM. Surgical repair of distal biceps tendon rupture complicated by median nerve entrapment. A case report. J Bone Joint Surg Am 2001;83:741-3. 13. Links AC, Graunke KS, Wahl C, Green JR 3rd, Matsen FA 3rd. Pronation can increase the pressure on the posterior interosseous nerve under the arcade of Frohse: a possible mechanism of palsy after twoincision repair for distal biceps rupturedclinical experience and a cadaveric investigation. J Shoulder Elbow Surg 2009;18:64-8. 14. Mokhtee DB, Brown JM, Mackinnon SE, Tung TH. Reconstruction of posterior interosseous nerve injury following biceps tendon repair: case report and cadaveric study. Hand (NY) 2009;4:134-9. 15. Morrey BF, Askew LJ, An KN, Dobyns JH. Rupture of the distal tendon of the biceps brachii. A biomechanical study. J Bone Joint Surg Am 1985;67:418-21. 16. Ramsey ML. Distal biceps tendon injuries: diagnosis and management. J Am Acad Orthop Surg 1999;7:199-207. 17. Stearns K, Sarris I, Sotereanos D. Permanent posterior interosseous nerve palsy following a two-incision distal biceps tendon repair. Orthopedics 2004;27:867-8. 18. Weinstein DM, Ciccone Ii WJ, Buckler MC, Balthrop PM, Busey TD, Elias JJ. Elbow function after repair of the distal biceps brachii tendon with a two-incision approach. J Shoulder Elbow Surg 2008;17 (1, suppl 1):S82-6.
www.elsevier.com/locate/ymse
CASE REPORTS
Delayed onset of posterior interosseous nerve palsy after a nonanatomic routing of a distal biceps repair: A case report Kristofer S. Matullo, MD, Nicholas L. Strasser, MD, Allen T. Bishop, MD, Alexander Y. Shin, MD, Bassem T. Elhassan, MD* Mayo Clinic, Rochester, MN Rupture of the distal biceps tendon is an uncommon injury.7,15 Conservative management of distal biceps ruptures has been reported to lead to a loss of power and endurance in elbow flexion and forearm supination.1,15 Surgical repair using a single- or double-incision technique has been recommended by most authors to restore elbow flexion and supination strength, especially in young active patients.18 Injury to the posterior interosseous nerve (PIN) has been reported to be more common with the singleincision technique, whereas heterotopic ossification and synostosis of the proximal radioulnar joint has been reported to be more common with the double-incision technique.2,3,5,6,8,11 Cases have also been reported of tendon rerupture, reflex sympathetic dystrophy, and neurologic injury, including the median nerve, superficial sensory branch of the radial nerve, lateral antebrachial cutaneous nerve, and anterior interosseous nerve, as well as temporary and permanent deficits of the PIN.3,5,6,10-12,17 We present a very rare complication of a distal biceps tendon repair performed through the double-incision technique. The tendon was fixed to the radial tuberosity but was routed laterally to the radius, with resultant radial nerve compression and delayed PIN palsy. To our knowledge, this complication has not been reported previously in the literature. The patient was informed of and agreed to publishing his case. *Reprint requests: Bassem T. Elhassan, MD, The Mayo Clinic, Gonda 14, Rochester, MN 55905. E-mail address: [email protected] (B.T. Elhassan).
Case report A 48-year-old farmer presented to our institution with symptoms of loss of forearm supination and weakness of thumb, finger, and wrist extension in his dominant right arm. He had sustained a distal biceps tendon rupture 18 months earlier after lifting a heavy object that was treated elsewhere with a 2-incision repair.4 His examination before the surgical repair demonstrated significant weakness in flexion and supination but showed he was otherwise neurologically intact. After surgery, the patient was placed in a long arm cast with his elbow in 90 of flexion for 3 weeks, followed by a hinged elbow brace with gradual extension for 3 weeks. He was started on active assisted range of motion exercises beginning 6 weeks after surgery. During his rehabilitation, he was not able to actively supinate his forearm with the elbow flexed despite extensive physical therapy. This problem was further complicated by progressive extension weakness of the wrist, thumb, and fingers, which started almost 10 months after his tendon repair. He was referred to us for further evaluation of the progressive hand weakness. The examination showed the previous surgical wounds appeared well healed, with no overlying skin changes or tenderness to palpation. His active elbow motion demonstrated a 135 arc of flexion from full extension to 135 of flexion. Active forearm pronation was 65 . Supination was very limited when the elbow was actively flexed to 90 but improved to 30 with the elbow extended. The most striking finding was the
1058-2746/$ - see front matter Ó 2010 Journal of Shoulder and Elbow Surgery Board of Trustees. doi:10.1016/j.jse.2009.11.054
e2
K.S. Matullo et al.
Figure 1 (A-D) Magnetic resonance imaging demonstrates the biceps tendon ()) traveling around the lateral side of the radius to insert on the bicipital tuberosity (arrow).
observation of obligate forearm pronation during active elbow flexion. When the elbow was passively flexed, however, concomitant forearm pronation was not present. His passive elbow and forearm motions were similar to the contralateral side except for a 10 loss of passive supination of the injured side (70 ) compared with the contralateral side (80 ). Examination of the hand and wrist demonstrated full passive range of motion, but the patient lacked active extension of his fingers at the level of the metacarpophalangeal joints. He had full extension of his wrist into radial deviation but could not maintain straight or ulnarly deviated wrist extension. Strength testing was grade 5 in the triceps and biceps, grade 4 of the extensor carpi radialis longus and extensor carpi radialis brevis, grade 3 of the extensor carpi ulnaris, grade 2 of the supinator, grade 1 of the extensor digitorum communis, and grade 0 of the extensor digiti quinti, extensor indices proprius, and extensor pollicis longus. Sensory examination showed intact sensation over the radial aspect of the wrist, dorsal aspect of the thumb, and in all fingers. These findings were consistent with a PIN palsy.
Radiographs of the right elbow demonstrated minimal heterotopic ossification at the level of the radial tuberosity. Electromyelographic evaluation was consistent with a PIN palsy without involvement of the superficial sensory branch of the radial nerve. Magnetic resonance imaging of the elbow and distal forearm showed evidence of a healed biceps tendon to the radial tuberosity; however, the biceps tendon appeared to be routed laterally rather than medially to the proximal radius at the level of the tuberosity (Fig. 1). Because of these findings, the patient underwent surgical exploration of the biceps tendon and PIN through the previous incisions. The posterior incision was extended, and after extensive scar release, it was evident that the biceps tendon was routed incorrectly around the lateral border of the radius between the PIN and the superficial sensory branch of the radial nerve (Figs. 2 and 3). Extensive scarring was also observed surrounding the proper radial nerve, the proximal radioulnar joint, and the PIN at the level of the malrouted biceps tendon and extending through the supinator muscle. The biceps tendon was released from its aberrant attachment and was delivered through the anterior wound. Release of the supinator and proximal radioulnar joint with
Biceps repair and PIN palsy
e3
Figure 3 Intraoperative photograph demonstrates the biceps tendon ()) passing superficially to the posterior interosseous nerve (white arrow) and deep to the superficial sensory branch of the radial nerve (black arrow).
hand function. He returned back to his preinjury work without restriction and was working out regularly without complaint.
Discussion
Figure 2 Intraoperative photograph demonstrates the biceps tendon passing around the lateral border of the radius.
concomitant neurolysis of the radial nerve and PIN was performed. Full passive supination was regained in the operating room. The biceps tendon was then correctly routed along the medial border of the radius and attached to the radial tuberosity using a trough and transosseous sutures. The patient was managed with a sling postoperatively, allowing active flexion of the elbow from 90 to full flexion for 4 weeks, followed by progressive extension of the elbow over a 2-week period. He was allowed full active flexionextension of the elbow, with active assisted range of motion for forearm rotation starting at 6 weeks. He was allowed unrestricted range of motion of the elbow and forearm at 3 months, with progressive strengthening at 4 months. At 7 months postoperatively, the patient had full range of motion of the elbow joint, forearm pronation of 70 , and supination of 50 , regardless of the elbow flexion angle. Strength testing of the biceps revealed 60 pounds on the left and right, and pronation was 40 pounds bilaterally; however, supination was limited to 20 pounds on the right compared with 40 pounds on the left. The patient regained full wrist extension and full finger extension with the wrist held in a neutral position. At 1 year after surgery, range of motion, flexion and pronation strength were maintained. Supination strength increased to 30 pounds. He subjectively rated his injured arm at 90% compared with the contralateral elbow and
Distal biceps tendon rupture is an uncommon injury that typically occurs when the forearm is rapidly extended against resistance, resulting in a rupture from the radial bicipital tuberosity.5,15,16 Surgical treatment is offered in an attempt to restore normal function to the elbow. Symptomatic management of these injuries without surgical fixation results in a decrease in endurance and a loss of supination strength by 40% and flexion strength by an average of 30%.1,15 Surgical biceps tenodesis to the brachialis is an option for the elderly or lower-demand patient that results in a decrease in supination strength of 50% but nearly normal flexion strength.15 Primary repair, however, helps to restore motion as well as flexion and supination strength and endurance to nearly normal values.18 Complications of biceps tendon repair are varied, but increase with a more prolonged time to surgical fixation.11 Boyd and Anderson4 described a 2-incision technique to help reduce the rate of neurologic complications, but there is a higher reported rate of heterotopic ossification compared with a single-incision repair, tenodesis, or conservative management.2,5,6,11 Complete synostosis of the proximal radioulnar joint has also occurred, preventing forearm pronosupination,3,8 and tendon rerupture and reflex sympathetic dystrophy have also been described. 3,6,11 Posterior interosseous nerve injury may result in decreased strength and inability to extend the fingers and thumb, as well as radial deviation with dorsal wrist extension due to the unopposed pull of the extensor carpi radialis longus tendon. The PIN has been reported to have a lower rate of injury with a double-incision approach than with the single Henry incision.4,9 Injury to the PIN can still occur with the double-incision technique, possibly due to traction
e4
K.S. Matullo et al.
Figure 4 An example of biceps tendon repair through double incision technique performed in a fresh cadaver elbow. Notice the proximity of the biceps tendon (red arrow) to the PIN (black arrow) and superficial branch of the radial nerve (black circle).
Figure 5 Recreation of the complication reported in this manuscript using a fresh frozen cadaver elbow. Notice how the aberrant passage of the biceps tendon laterally may pass between the two main branches of the radial nerve at the elbow and potentially compresses the PIN.
or aberrant retractor placement during the posterior exposure and attachment of the tendon to the tuberosity.14 Position of the forearm during biceps repair is also an important factor in nerve injury. Although it is commonly reported that positioning the forearm in pronation protects the PIN during biceps repair through the posterolateral approach, a recent report has suggested that the pronated position may lead to increased pressure on the nerve as it travels through the supinator.13 In addition, during biceps tendon repair using a single-incision technique, the forearm should be placed in supination to keep the nerve more lateral and away from the surgical repair site. Figure 4 shows an example of biceps tendon repair performed in a fresh frozen cadaveric elbow through the doubleincision technique. Notice how close the biceps tendon is to the PIN, which indicates that potential injury to this nerve is possible with either the single- or double-incision technique. Positioning of the forearm and excessive retraction of the soft tissues containing the nerve are the main potential risk factors for nerve injury. Typically, PIN injury is a temporary neurapraxia that resolves at average of 2 to 6 months after fixation;5,11 however, permanent damage has been reported.
To our knowledge, the case we are reporting here has not been reported previously. Routing the biceps tendon laterally around the proximal radius at the level of the tuberosity is a rare technical error that may occur with a surgeon’s unfamiliarity of elbow anatomy. This abnormal rerouting will likely always cause compression of the PIN unless the tendon is passed deep to the visualized nerve. In Figure 5 we tried to replicate the injury in a fresh frozen cadaveric elbow. Notice how the passage of the biceps tendon laterally may pass between the 2 main branches of the radial nerve at the elbow and leads to compression of the PIN. We believe that the progressive PIN palsy developed as a result of compression by the malrouted biceps tendon combined with the extensive scar accumulation. Previous delayed PIN neurapraxia has been described with a gradual decrease in PIN function occurring 4 months after repair.10 Exploration in this patient demonstrated scar formation of the proximal 2 cm of the PIN within the supinator muscle. There was a full recovery 4.5 months after neurolysis. The original loss of function in our patient developed more slowly, over 10 months, and he obtained recovery of PIN function during the next 7 months postoperatively.
Biceps repair and PIN palsy Although his elbow function significantly improved, forearm supination still lacked full motion and strength. This could be partly related to recurrence of local scarring and the supinator release performed to decompress the PIN.
Conclusion Delayed onset of PIN palsy, secondary to a routing error in the surgical insertion of the biceps tendon through the double-incision technique is a very rare complication of biceps tendon repair. During fixation of the tendon to the bicipital tuberosity, the tendon should be passed ulnarly and distally to radius neck. If the entire tendon is visualized or partially seen laterally as coursing from superior to inferior, the potential of malrouting should be considered. Aberrant routing may cause abnormal obligate forearm pronation with elbow flexion, neurapraxia due to scar formation, and direct PIN compression. Reversal of the abnormally routed tendon should be done as soon as it is recognized to improve the chance of recovery of elbow and forearm motion as well as PIN function.
Disclaimer The authors, their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.
References 1. Baker BE, Bierwagen D. Rupture of the distal tendon of the biceps brachii. Operative versus non-operative treatment. J Bone Joint Surg Am 1985;67:414-7. 2. Bell RH, Wiley WB, Noble JS, Kuczynski DJ. Repair of distal biceps brachii tendon ruptures. J Shoulder Elbow Surg 2000;9:223-6.
e5 3. Bisson L, Moyer M, Lanighan K, Marzo J. Complications associated with repair of a distal biceps rupture using the modified two-incision technique. J Shoulder Elbow Surg 2008;17(1 suppl. 1):S67-71. 4. Boyd HB, Anderson LD. A method for reinsertion of the distal biceps brachii tendon. J Bone Joint Surg Am 1961;43:1041-3. 5. Chillemi C, Marinelli M, De Cupis V. Rupture of the distal biceps brachii tendon: conservative treatment versus anatomic reinsertiondclinical and radiological evaluation after 2 years. Archives Orthop Trauma Surg 2007;127:705-8. 6. Cohen MS, Katolic L. Complications of distal biceps tendon repairs. Op Tech Sports Med 2003;11:60-6. 7. Davis WM, Yassine Z. An etiological factor in tear of the distal tendon of the biceps brachii; report of two cases. J Bone Joint Surg Am 1956;38:1365-8. 8. Failla F, Amadio PC, Morrey BF, Beckenbaugh RD. Proximal radioulnar synostosis after repair of distal biceps brachii rupture by the twoincision technique: report of four cases. Clin Orthop 1990;253:133-6. 9. Hovelius L, Josefsson G. Rupture of the distal biceps tendon. Report of five cases. Acta Orthop Scand 1977;48:280-2. 10. Katzman BM, Caligiuri DA, Klein DM, Gorup JM. Delayed onset of posterior interosseous nerve palsy after distal biceps tendon repair. J Shoulder Elbow Surg 1997;6:393-5. 11. Kelly EW, Morrey BF, O’Driscoll SW. Complications of repair of the distal biceps tendon with the modified two-incision technique. J Bone Joint Surg Am 2000;82:1575-81. 12. Lin KH, Leslie BM. Surgical repair of distal biceps tendon rupture complicated by median nerve entrapment. A case report. J Bone Joint Surg Am 2001;83:741-3. 13. Links AC, Graunke KS, Wahl C, Green JR 3rd, Matsen FA 3rd. Pronation can increase the pressure on the posterior interosseous nerve under the arcade of Frohse: a possible mechanism of palsy after twoincision repair for distal biceps rupturedclinical experience and a cadaveric investigation. J Shoulder Elbow Surg 2009;18:64-8. 14. Mokhtee DB, Brown JM, Mackinnon SE, Tung TH. Reconstruction of posterior interosseous nerve injury following biceps tendon repair: case report and cadaveric study. Hand (NY) 2009;4:134-9. 15. Morrey BF, Askew LJ, An KN, Dobyns JH. Rupture of the distal tendon of the biceps brachii. A biomechanical study. J Bone Joint Surg Am 1985;67:418-21. 16. Ramsey ML. Distal biceps tendon injuries: diagnosis and management. J Am Acad Orthop Surg 1999;7:199-207. 17. Stearns K, Sarris I, Sotereanos D. Permanent posterior interosseous nerve palsy following a two-incision distal biceps tendon repair. Orthopedics 2004;27:867-8. 18. Weinstein DM, Ciccone Ii WJ, Buckler MC, Balthrop PM, Busey TD, Elias JJ. Elbow function after repair of the distal biceps brachii tendon with a two-incision approach. J Shoulder Elbow Surg 2008;17 (1, suppl 1):S82-6.