Impact of metacarpal shortening on finger strength following non-surgical treatment of spiral and oblique metacarpal shaft fractures.

Abstract

Background: Treatment options for spiral/oblique metacarpal shaft fractures (MSFs) include both operative and non-operative approaches. Non-operative treatment with early mobilization has been shown to reduce treatment costs and sick leave, while maintaining grip strength despite metacarpal shortening. However, the impact of metacarpal shortening on strength at the metacarpophalangeal (MCP) or proximal interphalangeal (PIP) joints remains unclear. This study aimed to evaluate whether a shortening of more than 2 mm in spiral/oblique MSFs affects the strength of a single finger.

Methods: A total of 23 patients with metacarpal shortening greater than 2 mm following a spiral/oblique MSF were included. The primary outcomes were flexion and extension strength in the MCP and PIP joints, compared to the uninjured hand. Secondary outcomes included range of motion, grip strength, metacarpal shortening, DASH score, patient satisfaction, pain levels, and return to work.

Results: There were no differences observed in grip strength, range of motion, or MCP joint extension. However, PIP joint flexion and extension, as well as MCP joint flexion, were significantly reduced. The DASH scores were generally low (mean 4, range 0-23), with patients reporting no pain and high satisfaction.

Conclusions: In conclusion, finger strength was statistically significantly reduced, but its clinical relevance remains unclear. Despite these findings, the low DASH scores and high patient satisfaction suggest that the functional impact of these changes may be minimal for most patients. We recommend discussing these findings with individuals who heavily rely on dexterity, such as professional musicians or other precision skill workers.

Level of evidence: IV.