Abstract
The ulnar collateral ligament (UCL) of the thumb is situated on the inner side of the thumb, near the ulnar aspect of the metacarpophalangeal joint. It plays a crucial role in stabilizing the base of the thumb and contributes to grip strength and overall hand function. UCL injuries account for approximately 86% of all injuries affecting the base of the thumb. Treatment for UCL injuries varies depending on severity. When the UCL of the thumb is completely torn, surgical intervention becomes necessary. Significant gaps in the literature still exist despite the growing number of publications on the surgical treatment of complete thumb UCL tears. Thus, this systematic review synthesized existing research to evaluate the functional and clinical outcomes of surgical treatments for complete UCL ruptures of the thumb across athletes and the general population. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines. However, the review protocol was not prospectively registered in a systematic review database such as PROSPERO. Articles published between January 1, 2015 and January 30, 2025 were identified through reputable databases including PubMed, PubMed Central, Europe PubMed Central, ScienceDirect, Embase, and Google Scholar. This review included English-language studies with accessible full texts, conducted on human subjects; 12 studies were reviewed for analysis. The Assessment of Multiple Systematic Reviews 2 (AMSTAR2) critical appraisal tool was used to evaluate all selected systematic reviews, and the Newcastle-Ottawa Scale (NOS) was used to assess the cohort and longitudinal studies. A total of 335 patients from 12 studies were analyzed, with follow-up ranging from 6 months to 15 years. The studies included retrospective and prospective cohorts, as well as systematic reviews. Surgical techniques varied and included suture anchors, tendon grafts, suture tape augmentation, and novel methods such as ultrasound-welded anchors and U-shaped Kirschner wires. Most studies reported favorable outcomes in joint stability, range of motion, strength, pain relief, and patient satisfaction. Among athletes, return-to-sport rates were high (up to 98.1%), often within 5-8 weeks postoperatively. Conclusions indicate that surgical management remains the gold standard for complete UCL tears of the thumb, particularly in cases involving Stener lesions, joint instability, or failed conservative treatment. Techniques such as suture anchor repair, tendon graft reconstruction, and internal brace augmentation consistently yield favorable functional and clinical outcomes, including restored strength, reduced pain, and high patient satisfaction. Although earlier intervention generally leads to better results, positive outcomes are observed across diverse populations. This review highlights the need for high-quality randomized controlled trials to standardize surgical indications, techniques, and postoperative care.