Do Short-Term Effects Predict Long-Term Improvements in Women Who Receive Manual Therapy or Surgery for Carpal Tunnel Syndrome? A Bayesian Network Analysis of a Randomized Clinical Trial

Objective. The purpose of this study was to develop a data-driven Bayesian network approach to understand the potential multivariate pathways of the effect of manual physical therapy in women with carpal tunnel syndrome (CTS). Methods. Data from a randomized clinical trial (n = 104) were analyzed comparing manual therapy including desensitization maneuvers of the central nervous system versus surgery in women with CTS. All variables included in the original trial were included in a Bayesian network to explore its multivariate relationship. The model was used to quantify the direct and indirect pathways of the effect of physical therapy and surgery on short-term, mid-term, and long-term changes in the clinical variables of pain, related function, and symptom severity. Results. Manual physical therapy improved function in women with CTS (between-groups difference: 0.09; 95% CI =0.07 to 0.11). The Bayesian network showed that early improvements (at 1 month) in function and symptom severity led to longterm (at 12 months) changes in related disability both directly and via complex pathways involving baseline pain intensity and depression levels. Additionally, women with moderate CTS had 0.14-point (95% CI =0.11 to 0.17 point) poorer function at 12 months than those with mild CTS and 0.12-point (95% CI =0.09 to 0.15 point) poorer function at 12 months than those with severe CTS. Conclusion. Current findings suggest that short-term benefits in function and symptom severity observed after manual therapy/surgery were associated with long-term improvements in function, but mechanisms driving these effects interact with depression levels and severity as assessed using electromyography. Nevertheless, it should be noted that betweengroup differences depending on severity determined using electromyography were small, and the clinical relevance is elusive. Further data-driven analyses involving a broad range of biopsychosocial variables are recommended to fully understand the pathways underpinning CTS treatment effects. Impact. Short-term effects of physical manual therapy seem to be clinically relevant for obtaining long-term effects in women with CTS. Keywords: Bayesian Networks, Carpal Tunnel Syndrome, Machine Learning, Manual Therapy
Introduction Carpal tunnel syndrome (CTS) is the most prevalent entrapment neuropathy of the upper extremity. Although there is no consensus on which treatment option should be applied as first-line management, [...]