Tenets of flexor and extensor tendon repair

Abstract

Injuries to the flexor and extensor tendons frequently are seen by hand and orthopaedic surgeons. The anatomical differences between flexor and extensor tendons are paramount when considering the diagnosis and treatment options. Treatment is largely dictated based on the zone of injury. Fundamental concepts have been established over the years regarding repair technique. These include size of core suture placement, suture configuration, location of suture placement, and addition of an epitendinous suture. Type of anesthesia is another factor to consider, as wide-awake surgery has recently become popular because the surgeon can assess tendon gliding and gap formation with active motion during surgery. Recent research has focused on the role of biologics. Growth factors and transcription factors including vascular endothelial growth factor (VEG-F), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB), transforming growth factor beta (TGF-B), matrix metallopeptidase 9 (MMP-9), and bone morphogenetic protein (BMP-12) have all been implicated in contributing to the tendon healing environment. Biologics represents a novel treatment modality aimed at altering the tendon healing environment to reduce adhesion formation to facilitate tendon gliding, while also allowing for a strong repair.