Comparison of two immobilization techniques for radiological outcomes in fifth metacarpal neck fractures: a prospective controlled study.

PURPOSE: Although fifth metacarpal neck fractures are commonly managed conservatively, there is no consensus regarding the optimal immobilization strategy. The aim of this study was to compare the radiographic outcomes of the Jahss Position Splint (JPS) and the conventional Ulnar Gutter Splint (UGS) in the treatment of fifth metacarpal neck fractures.

METHODS

A total of 78 adult male patients treated for isolated closed fifth metacarpal neck fractures between January 2023 and June 2024 were prospectively evaluated. Patients were allocated to either the JPS group (n = 42) or the UGS group (n = 36). Patients were assigned to JPS or UGS according to the predefined odd/even-calendar-day duty schedule of two surgeons, each of whom routinely applied one of the techniques. All patients underwent closed reduction using the Jahss maneuver followed by three weeks of immobilization. Radiographic outcomes included initial fracture angulation (IFA), post-reduction angulation (PRA), final follow-up angulation at 12 weeks (FFA), metacarpal shortening, and malunion rates.

RESULTS

No significant differences were observed between the groups regarding age or IFA (p > 0.05). Correction during reduction and splint application was greater with JPS than with UGS (15.2 ± 9.6° vs. 8.9 ± 11.0°; p = 0.009), whereas subsequent loss of reduction during immobilisation did not differ significantly between the groups (2.8 ± 8.4° vs. 1.0 ± 9.8°; p = 0.388).The JPS group demonstrated significantly lower PRA (p < 0.001) and FFA (p = 0.003) compared with the UGS group. Metacarpal shortening was significantly less in the JPS group (p = 0.036). The malunion rate was 5% in the JPS group and 28% in the UGS group (p = 0.009).

CONCLUSION

JPS was associated with greater immediate angular correction and more favourable final radiographic outcomes than UGS but did not reduce subsequent loss of reduction during immobilisation. Because functional and patient-reported outcomes were not assessed, the clinical relevance of these radiographic differences remains uncertain.