Extensor pollicis longus tendon rupture secondary to elastic intramedullary nailing of paediatric forearm fractures: how to avoid them?

Extensor Tendon Injury Associated With Dorsal Entry Flexible Nailing of Radial Shaft Fractures in Children: A Report of 5 New Cases and Review of the Literature

BACKGROUND

Extensor pollicis longus (EPL) tendon injury following the dorsal approach to elastic stable intramedullary nailing (ESIN) of the radius has been reported in a growing number of cases in the literature. This study includes 5 new cases from our institution as well as a comprehensive review of previously reported cases from the literature.

METHODS

We conducted a retrospective chart review of all patients undergoing ESIN between January 1, 2004 and December 31, 2013 at our institution. Those patients with an EPL injury or rupture were identified and clinical data collected included operative technique, diagnosis, treatment, and outcomes data. In addition, we performed a systematic review of the literature using Pubmed MEDLINE database, the Chochrane database, Scopus, Web of Science, and Embase. A total of 28 cases of EPL injury following ESIN of the radius were identified in the literature and the relevant data were extracted from those studies.

RESULTS

All 33 pediatric cases of EPL tendon injury occurred after entry to the radial canal was obtained by the dorsal approach to ESIN. EPL injury was diagnosed an average of 10 weeks following the index procedure. Extensor indicis pollicis to EPL transfer was performed in 13 patients, tendon release/lysis of adhesions in 5, EPL repair in 2, EPL graft reconstruction from palmaris longus tendon in 1, 3 patients refused further intervention, and treatment was unreported in 7 cases. By 12-month follow-up, all operatively treated patients had a good functional outcome with near anatomic extension at the thumb interphalangeal joint, no pain, and no further complication.

CONCLUSIONS

EPL tendon injury was found to be a complication unique to the dorsal entry approach for ESIN of the radius. The lateral approach appears to offer a safer alternative with regard to the EPL tendon. We suggest that physicians consider the risk of EPL tendon injury when planning for ESIN of the radius, and make an effort to avoid direct injury when using a dorsal approach.

LEVEL OF EVIDENCE

Level III-therapeutic.

Incidence and Risk Factors for Extensor Pollicis Longus Rupture in Elastic Stable Intramedullary Nailing of Pediatric Forearm Shaft Fractures

BACKGROUND

Elastic stable intramedullary nailing (ESIN) is an effective means of fixation for unstable, pediatric forearm shaft fractures with the benefit of smaller incisions, less soft tissue manipulation, and ease of removal. This study was designed to evaluate the incidence of and risk factors for extensor pollicis longus (EPL) rupture after fixation of pediatric radial shaft fractures with ESIN.

METHODS

A retrospective review of all patients younger than 19 years who had a repair of a forearm fracture with flexible intramedullary nailing between 2006 and 2011 was performed. Nineteen consecutive patients were identified from the electronic medical record. All patients were treated with a titanium elastic nailing system using a dorsal approach to the radius. The patients were followed postoperatively for at least 2 years, and all fractures healed. An extensive chart review assessing for persistent pain, EPL function, and risk factors for EPL rupture was performed. Implants were removed in all but 1 patient.

RESULTS

Seventeen records were available for review. Fourteen (82%) were male, and the mean age at time of fracture was 10 years old (range, 5 to 14 y). Follow-up averaged 5.5 years (range, 2.9 to 7.8 y). The mean weight was 32.7 kg for males and 50.6 kg for females corresponding to the 61st and 60th percentile respectively of weight-for-age (range, 8th to 99.9th percentile). Hardware was removed in all but 1 case, and the median time from surgery to hardware removal was 21 weeks (range, 8 to 63). Three of the 17 patients (18%) experienced rupture of the EPL. Two were treated with additional surgery following hardware removal, and one was untreated due to patient preference. None of the 17 patients (including those with rupture) had independent risk factors for tendon rupture: inflammatory arthritis, diabetes, or prior steroid use. Time to removal, patient age, and percentile of weight-for-age did not correlate with EPL rupture.

CONCLUSIONS

Although ESIN of pediatric forearm shaft fractures has gained acceptance as a treatment option, our series of 17 patients revealed an 18% rate of EPL rupture. With this small patient cohort, no patient characteristics proved to be significant risk factors for predicting tendon rupture. However, awareness should be raised for an increased risk of EPL rupture with this fixation method.

LEVEL OF EVIDENCE

Level IV-Therapeutic.

Rupture of the extensor pollicis longus tendon following dorsal entry flexible nailing of radial shaft fractures in children

INTRODUCTION

Diaphyseal forearm fractures are common in children and adolescents. Intramedullary fixation with flexible nails has a high success rate. Complications related to the insertion of the radial nail include injury to the superficial branch of the radial nerve and rupture of the extensor pollicis longus (EPL) tendon.

MATERIALS AND METHODS

We report a series of nine patients who sustained an EPL injury related to the insertion of an elastic intramedullary nail into the radius.

RESULTS

All nine patients underwent operative management, consisting of either EPL release, EPL direct repair, or tendon transfer (using extensor indicis proprius). In all cases, the nail entry site was directly related to the location of EPL. In many of the cases the EPL dysfunction occurred early on but it's recognition was often delayed.

CONCLUSION

Based on our findings, we recommend the use of a radial entry point. For surgeons who prefer the dorsal entry point, we recommend that they use an incision which allows visualisation of the extensor tendons and that any post-operative EPL dysfunction is addressed promptly.