Occurrence of cold sensitivity in carpal tunnel syndrome and its effects on surgical outcome following open carpal tunnel release.

Cold sensitivity is common following nerve injuries in the upper extremity, but is less well studied in carpal tunnel syndrome (CTS). We investigated cold sensitivity in CTS and its effects on surgical outcome. A search of the Swedish National Registry for Hand Surgery (HAKIR) for open carpal tunnel releases (OCTR) from 2010-2016 identified 10,746 cases. Symptom severity questionnaires (HQ-8; HAKIR questionnaire 8, eight Likert-scale items scored 0-100, one item on cold sensitivity) and QuickDASH scores before and after surgery were collected. Patient mean age was 56 ± SD 16 years, and 7,150/10,746 (67%) were women. Patients with severe cold sensitivity (defined as cold intolerance symptom severity score > 70; n = 951), scored significantly higher on QuickDASH at all time points compared to those with mild cold sensitivity (cold intolerance symptom severity scores ≤ 30, n = 1,532); preoperatively 64 [50-75] vs. 40 [25-55], at three months 32 [14-52] vs. 18 [9-32] and at 12 months 25 [7-50] vs. 9 [2-23]; all p < 0.0001. Severe cold sensitivity predicted higher postoperative QuickDASH scores at three [12.9 points (95% CI 10.2-15.6; p < 0.0001)] and at 12 months [14.8 points (11.3-18.4; p < 0.0001)] compared to mild cold sensitivity, and adjustment for a concomitant condition in the hand/arm, including ulnar nerve compression, did not influence the results. Cold sensitivity improves after OCTR. A higher preoperative degree of cold sensitivity is associated with more preoperative and postoperative disability and symptoms than a lower degree of cold sensitivity, but with the same improvement in QuickDASH score.