A systematic review of patient outcomes for primary pediatric flexor tendon repairs

Background: Literature on pediatric flexor tendon repairs remains sparse. Given the various repair techniques and rehabilitation protocols available, the aim of this systematic review is to investigate outcomes of primary pediatric flexor tendon repairs. Methods: MEDLINE, Embase, PubMed, and Cochrane Central Register of Controlled Trials databases were searched from inception to June 2022 in concordance with PRISMA guidelines. Studies were included if patients were under the age of 18, sustained a flexor tendon injury repaired primarily, and had documented functional outcomes. Quality assessment was completed using the Newcastle-Ottawa Scale. The study was registered with PROSPERO (CRD42018089089). Results: This study includes 20 articles representing 577 patients with 748 injured digits, most frequently injured by a laceration from glass. The number of tendon injuries in zones I, II, III, IV, and V were 78, 431, 62, 2, and 19, respectively. In total, 594 FDP, 374 FDS, and 77 FPL tendons were lacerated. Concurrent digital nerve injuries occurred in 251 digits. Time of repair was 15 h-187 days post-injury, most commonly via the modified Kessler (n = 266 digits) and Kessler (n = 162 digits). Post-operatively, 170 patients were immobilized and 261 patients underwent early active (n = 96) or passive (n = 165) protocols. Functional outcomes were reported in 466 digits (excellent = 306, good = 132, fair = 19, and poor = 9, per the respective assessment tool used). There were 15 tendon ruptures. Conclusions: Despite heterogeneity in both operative and post-operative protocols, there is low level evidence that low complication rates and good outcomes are expected following primary repair of pediatric flexor tendons.