L-pinning for fifth metacarpal neck fracture in adolescents

Abstract

Introduction: Fifth metacarpal neck fracture is the most frequent type of hand fracture in adolescents between 13 and 16 years of age. It mainly affects males and the dominant hand. The L-pinning technique combines intramedullary anterograde pinning and transverse pinning between the 4^th and 5^th metacarpals. The present study aimed to assess L-pinning without postoperative immobilization in displaced 5^th metacarpal fracture in adolescents with low residual growth.

Materials and methods: Data for patients aged between 13 and 16 years, operated on for closed 5^th metacarpal neck fracture between January 2017 and June 2019, were analyzed retrospectively. Surgery was indicated for angulation with>30° palmar tilt and/or horizontal malalignment. The technique consisted in intramedullary anterograde pinning and transverse pinning between the 4^th and 5^th metacarpal heads. No postoperative immobilization was applied. Hardware was removed as of day 28. The final clinical check-up was at≥12 months.

Results: Eighteen patients, all male, with a mean age of 14 years, were included. All had bone age≥14 years. Mean palmar tilt was 52°±6.8° versus 6°±2.4° postoperatively, for a mean correction of 45°±4.3°. Mean operating time was 15min, and X-ray exposure 0.36minutes for a mean radiation dose of 2.89 cGy/cm². At hardware removal, all patients showed radiologic consolidation. At 3 months, 5^th ray ranges of motion were normal, with no local complications. Functional results were maintained at last follow-up (≥12 months).

Conclusion: L-pinning seemed reliable in terms of feasibility and stability of reduction in 5^th metacarpal neck fracture in adolescents. Absence of postoperative immobilization facilitated self-rehabilitation and accelerated functional recovery.

Level of evidence: IV.

Keywords: Adolescent fracture; Fifth metacarpal neck fracture; Hand fracture; L-pinning; Minimally invasive surgery.