Prognostic factors for outcome after median, ulnar, and combined median-ulnar nerve injuries: a prospective study.

Background: A major problem in the surgical treatment of peripheral nerve injuries of the upper extremities is the unpredictable final outcome. More insight and understanding of the prognostic factors is necessary to improve functional outcome after repair of the peripheral nerves. The objective of this study was to identify prognostic factors for the functional recovery of peripheral nerve injury of the forearm and their independent contribution in the outcome in the first year after reconstruction.

Methods: A multicentered prospective study in the Netherlands resulted in the inclusion of 61 patients with a median, ulnar, or combined median-ulnar nerve injury. The age, level of injury, type of nerve injury, number of damaged structures, number of damaged arteries, education, smoking, and posttraumatic stress were analyzed as prognostic factors for functional outcome after repair of the peripheral nerves. The outcome parameters were sensory recovery (Semmes-Weinstein monofilament test) and motor recovery (Medical Research Council (MRC) score, power grip, and pinch grip) and the ability to perform daily activities.

Results: Gender, age, level of education, number of injured arteries and structures, damaged nerve, location of the injury, type of the nerve injury, and posttraumatic stress at 1 and 3 months after repair of the peripheral nerve injury were found to be predictors of functional recovery.

Conclusions: Our prospective analysis of prognostic factors shows several factors to be predictive for the functional recovery after peripheral nerve injuries of the median and/or ulnar nerve of the forearm. Sensibility of the hand, power grip, and DASH score (DASH, Disabilities of Arm, Shoulder and Hand) have proven to be the three best prognostic factors in this study. Of these prognostic factors, only posttraumatic stress can be influenced to optimize functional outcome.