Median and Ulnar Nerve Injuries: Prognosis and Predictors for Clinical Outcome

This study investigated the overall long-term outcome of median and ulnar nerve injuries. Furthermore, the end-point for functional recovery was determined and predictors for the different outcome markers were quantified.

A longitudinal cohort study (n = 136), with a mean follow-up of 5.5 years, and a meta-analysis (n = 623) were performed. Parameters of outcome were sensory recovery (Semmes-Weinstein monofilaments and MRC scale), motor recovery (grip, tip-pinch strength, and MRC scale), restoration of activities of daily living (functional symptom score), psychological morbidity (impact of event scale), and the ability to return to work.

The meta-analysis showed that 44% of the median nerves reached “good” (S3+) sensory recovery and 61% “good” motor recovery (M4 or better). For ulnar nerve injuries, 41% reached “good” sensory recovery and 45% “good” motor recovery. Combined median-ulnar nerve injuries and “spaghetti wrist” injuries had worse prospects. Fifty-nine percent of the study population was able to return to work within 1 year and the mean time off work was 31 weeks; 19.36% of the subjects reported sufficient early post-traumatic psychological stress at 1 month postoperatively to be in need of psychological treatment (impact of event scale > 30). A significant improvement of sensory recovery was found up to 4 years following surgery. Motor recovery stabilized 3 years postoperatively. Age, delay, level of injury, cognitive capacity, type of injury, compliance to hand therapy, and early psychological stress seemed to be statistically significant predictors for final outcome.

Despite all efforts to improve functional outcome following nerve injuries, the clinical outcome is still far from ideal. The central nervous system is one of the leading predictors for clinical outcome. Early collaboration with a psychologist is essential to identify those patients who are likely to develop a post-traumatic stress disorder. Quantification of predicting variables will help create a prognostic model to predict final functional outcome.