Preoperative Diagnostic Factors Associated With Early MCID Achievement in BCTQ Outcomes Following Carpal Tunnel Release

Purpose: To evaluate whether commonly obtained preoperative diagnostic findings are associated with early clinically meaningful improvement in patient-reported outcomes after carpal tunnel release (CTR) and to assess the durability of any observed associations across early postoperative follow-up. Methods: This retrospective cohort study included patients who underwent CTR between 2012 and 2020 and completed standardized preoperative evaluation with carpal tunnel syndrome-6 scoring, ultrasound, and electrodiagnostic testing, along with Boston Carpal Tunnel Questionnaire assessments before surgery and at 2 and/or 6 weeks after surgery. Clinically meaningful improvement was defined using established minimal clinically important difference (MCID) thresholds for the Symptom Severity Scale and Functional Status Scale. Associations among preoperative diagnostic findings, demographic variables, and postoperative outcomes were evaluated using univariate, exploratory multivariable, and longitudinal generalized estimating equation analyses. Results: Ninety-nine patients were included. Boston Carpal Tunnel Questionnaire symptom and function scores improved at all postoperative timepoints, with more than half of patients achieving MCID by 6 weeks. At 2 weeks, abnormal sensory nerve action potential amplitude was associated with smaller functional improvement, whereas select demographic factors were associated with MCID achievement. At 6 weeks, prolonged distal sensory latency and distal motor latency were associated with higher odds of achieving Symptom Severity Scale MCID, and prolonged distal sensory latency was associated with greater symptom and functional score reductions. However, associations varied by outcome domain and timepoint, and no variable demonstrated a consistent longitudinal association with clinically meaningful improvement. Conclusions: Early recovery after CTR is characterized by substantial symptomatic and functional improvement but marked interpatient variability. Although select preoperative diagnostic and demographic factors demonstrated time-limited associations with early outcomes, when treated as cutoff values, no variable being abnormal reliably predicted clinically meaningful improvement in this cohort across early follow-up. These findings support the use of preoperative diagnostic testing cutoff thresholds primarily for diagnostic confirmation and clinical decision-making rather than for prognosticating early postoperative recovery. Type of study/level of evidence: Prognostic IV.