Posterior plating via posterolateral approach for posterior malleolar fractures: Effect on flexor hallucis longus morphology and function-a cohort study.

BACKGROUND

Posterior plating through the posterolateral approach for posterior malleolar fractures (PMF) has been advocated for direct reduction and stable fixation, but its effect on the flexor hallucis longus (FHL) muscle has not yet been clearly defined.

PURPOSE: To evaluate postoperative changes in FHL morphology and function after posterior plating of PMFs through a posterolateral approach.

STUDY

DESIGN

Retrospective cohort with cross-sectional follow-up assessment.

METHODS

Sixty-eight patients who underwent fixation of PMFs with a posterior one-third tubular plate through a posterolateral approach were evaluated at a minimum of 1 year after surgery. Mean age was 43.81 ± 14.36 years, and mean follow-up was 21.01 ± 10.81 months. The operated side was compared with the contralateral side for hallux range of motion, unilateral heel rise (UHR) performance, maximum voluntary isometric contraction (MVIC) strength, and ultrasonographic FHL thickness and cross-sectional area (CSA). Clinical outcomes were assessed using the Foot Function Index (FFI).

RESULTS

The operated side showed significantly lower hallux plantarflexion and dorsiflexion, UHR and MVIC performance, and FHL thickness and CSA than the contralateral side (all p < .001). No checkrein deformity was observed. Mean FFI was 2.37 ± 2.42.

CONCLUSION

Posterior plating of posterior malleolar fractures through a posterolateral approach was associated with measurable alterations in FHL muscle morphology but these alterations were not reflected in patient-reported outcomes, and ROM values remained within functional limits.