Endoscopic versus Open In Situ Cubital Tunnel Release: A Systematic Review of the Literature and Meta-Analysis of 655 Patients

Background: Cubital tunnel syndrome is the second most common peripheral entrapment syndrome. To date, there is no true consensus on the ideal surgical management. A minimally invasive, endoscopic approach has gained popularity but has not been adequately compared to the more traditional, open approach. Methods: With compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic review was performed to identify studies published between 1990 and 2016 that compared the efficacy of endoscopic cubital tunnel release to open cubital tunnel release. A meta-analysis was then performed through a random-effects model with inverse variance weighting to calculate I-2 values for heterogeneity analysis. Forest plots were constructed for each analysis group. Results: Five studies involving 655 patients (endoscopic cubital tunnel release, n = 226; open cubital tunnel release, n = 429) were included. Meta-analysis revealed no significant superiority of open release in achieving an excellent or good Bishop score (OR, 1.27; 95 percent CI, 0.59 to 2.75; p = 0.54) and reduction in visual analogue scale score (mean difference, -0.41; 95 percent CI, -1.49 to 0.67; p = 0.46). However, in the endoscopic release cohort, lower rates of new-onset scar tenderness/elbow pain were found (OR, 0.19; 95 percent CI, 0.07 to 0.53; p = 0.002), but there was a higher incidence of postoperative hematomas (OR, 5.70; 95 percent CI, 1.20 to 27.03; p = 0.03). The reoperation rate in the endoscopic and open release groups was 4.9 and 4.1 percent, respectively (p = 0.90). Conclusions: The authors demonstrated equivalent overall clinical improvement between endoscopic and open cubital tunnel release in terms of Bishop score and visual analogue scale score reduction. Because of the low power of most studies, further investigations with a larger patient population and longer follow-up are needed to better characterize the role of endoscopic cubital tunnel release.