The Effect of Body Mass Index on Open Carpal Tunnel Release Recovery

The purpose of this study was to determine whether a relationship exists between body mass index (BMI), specifically obesity, and surgical outcomes for open carpal tunnel release. Obesity is correlated with increased incidence of carpal tunnel syndrome; however, the effect of obesity on after release recovery has not been examined.

This study used a retrospective review of patient charts (n = 142). BMI was calculated based on height and weight measurements, and patients were grouped based on their BMI into the following categories: healthy BMI (18.5-24.9 kg/m²), overweight (25-29.9 kg/m²), obesity class one (30-34.9 kg/m²) (OB1), obesity class (2 35-39.9 kg/m²) (OB2), or obesity class three (40+ kg/m²) (OB3). Data were then complied on surgical outcomes by assessing preoperative pain, postoperative pain at 2 and 6 weeks, postoperative joint stiffness, wound healing time, and infection status. Data were analyzed using chi-square analyses and multivariable logistic regression to assess the differences in treatment outcomes while controlling for possible confounding variables.

Age at the time of release was found to be inversely correlated with BMI. Healthy BMI patients (n = 19) underwent release at an average age of 59.1 years, whereas OB3 (n = 30) underwent release at an average age of 46.9 years. The odds of improvement in pain were significantly lower in all three obesity groups when compared with healthy BMI at both 2 and 6 weeks after operation.

Our results indicate that obesity may be positively correlated with earlier incidence of carpal tunnel syndrome requiring surgical intervention. These data also indicate the increased rates of postoperative complications in obese patients, particularly patients with OB3. Patients with OB3 need to understand these risks before undergoing open release. Further study should examine the impact of type 2 diabetes on carpal tunnel release recovery.

The information included in this study may be used to guide surgeons and patients when considering the effect and potential improvement in outcomes that may come from addressing patient BMI before open carpal tunnel surgery.