Self-Reported Improvement After Carpal Tunnel Release in Patients With Motor Axonal Loss

Abstract

Purpose

Electrodiagnostic studies can identify evidence of sensory and motor axonal loss (AL) in carpal tunnel syndrome (CTS) patients. However, the impact of sensory and motor AL on outcomes following carpal tunnel release (CTR) remains unclear. We hypothesize that patients with no evidence of sensory and motor AL will experience greater improvement following CTR compared to those with evidence of AL.

Methods

Patients undergoing open and endoscopic CTR by four fellowship-trained orthopedic hand surgeons were identified. Sensory and motor AL were identified using preoperative electromyography and nerve conduction studies. Patients completed the following before surgery and 3-month postoperative patient-reported outcomes: Patient-Reported Outcomes Measurement Information System Upper Extremity (UE) and Pain Interference (PI) as well as Disabilities of the Arm, Shoulder, and Hand (QuickDASH [QD]). Preoperative and postoperative scores, changes in scores, and rates of achieving the minimally clinically important difference (MCID) were compared between patients with and without sensory and motor AL.

Results

One hundred and seventy-five patients were included. Of these, 91 exhibited sensory AL and 98 exhibited motor AL. Demographic matched analysis of patients with and without sensory AL showed no differences in before surgery, after surgery, difference, or proportion meeting MCID for UE, PI, or QD. Matched analysis revealed no difference in preoperative PROMs between patients with and without motor AL. Patients with motor AL had increased postoperative UE (better function), decreased postoperative PI (less PI) and QD (less disability), increased changes in PI and QD, as well as a greater proportion meeting MCID for QD compared to those without motor AL.

Conclusions

There was no difference in post-CTR improvement between patients with and without sensory AL. However, contrary to our hypothesis, motor AL patients experienced greater postoperative improvement according to QD. These findings suggest surgery should be recommended for severe CTS patients with evidence of AL. These results can better inform physicians and patients as they discuss expectations of CTR outcomes.

Type of study/level of evidence

Prognosis II.