Comparison Of Endoscopic and Open Decompression of The Ulnar Nerve in Cubital Tunnel Syndrome: A Systematic Review with Meta-Analysis

Cubital tunnel syndrome (CTS) is the second most common compressive neuropathy of the upper limb, associated with symptoms of pain, paresthesia and hand weakness, with a significant impact on patients' quality of life.1 The primary surgical treatment is decompression of the ulnar nerve using the open in situ technique, with good scientific evidence and a low complication rate. 2 Minimally invasive techniques, such as endoscopic in situ decompression (EISD), have emerged as an alternative, promising smaller scars, less postoperative pain and faster functional return. Doubts remain about the safety, efficacy and complication profile of these techniques when compared to open in situ decompression (OISD).2 Randomized clinical trials, such as those by Elwenspoek et al. in 2014-2017 with 45 patients, showed equivalence in clinical outcomes (Bishop's excellent/optimal score between 90-96%), but with less chronic scar pain and better aesthetic satisfaction in the endoscopic group, albeit with a longer operative time. Another randomized double-blind study (2008-2011, 56 cases) corroborated the similarity of functional results, observing a higher incidence of hematomas in the endoscopic group. 2,3 Two contemporary meta-analyses consolidate this perception: The meta-analysis of 686 cases revealed endoscopic decompression with longer surgical duration, increased risk of hematoma and acute pain, but less postoperative paresthesia and better grip strength. And a previous meta-analysis comparing eight studies (582 patients) confirmed equivalent efficacy, highlighting less painful scar sensitivity in the endoscopic group .3 To this end, despite equivalence in functional and clinical outcomes, EISD offers advantages in terms of scar, chronic pain and grip strength, at the cost of longer surgical time and risk of hematoma, more robust and standardized studies are needed. This systematic review with meta-analysis aims to rigorously compare efficacy, safety and technical quality between endoscopic and open decompression of the ulnar nerve in CTS, with a focus on clinical impact and decision-making guidelines for orthopaedic practice.