The Risk of Acute Carpal Tunnel Syndrome in Lunate and Perilunate Dislocations.

PURPOSE: Lunate and perilunate dislocations are uncommon wrist injuries that have a high reported association with acute median neuropathy, frequently referred to as acute carpal tunnel syndrome (ACTS). Previous investigations into the incidence of lunate and perilunate dislocation and acute median neuropathy have often been limited by small sample sizes. The purpose of our study was to report a relatively large cohort examining the incidence of ACTS in lunate and perilunate dislocations and assess predictive risk factors.

METHODS

A retrospective review was performed of all lunate and perilunate dislocations at a single safety net level 1 trauma center from 2014 to 2023. Demographic data collected included age, sex, and medical comorbidities. Injury data included laterality, mechanism of injury, concomitant ipsilateral upper extremity fracture, time to reduction (closed or open), time to definitive surgery, and incidence of acute median neuropathy.

RESULTS

A total of 65 patients were included in the final cohort, with a mean age of 34 years, of whom 92% were male. Twenty-five percent of patients were diagnosed with acute carpal tunnel syndrome. In total, 65% of patients had perilunate dislocations, and 35% had lunate dislocations with no difference in risk of developing ACTS. No significant predictors for ACTS including demographic variables, mechanism of injury, concomitant boney injuries, and time to reduction were found.

CONCLUSIONS

We have demonstrated a 25% incidence of ACTS after lunate or perilunate dislocations without an identified impact of the direction of the dislocation, mechanism of injury, or time from injury to closed reduction.

TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.