Background: Fast-pitch softball is one of the fastest growing sports, but there is little research regarding pitcher fatigue. Currently, there are no pitch limits or game counts. Questions/Purposes: To study the effect of fatigue on youth fast-pitch softball pitchers during a high school season, we hypothesized increased games pitched during the season would correlate with increased player-reported pain and fatigue and decreased with upper extremity strength and range of motion (ROM). Methods: This prospective crosssectional study evaluated pre-and postgame shoulder and elbow strength, ROM, pain, and fatigue in 17 high school fast-pitch softball pitchers. These measures were recorded at two games, one at the beginning and one at the end of the season. Pitch count and number of games pitched during the season were recorded. We compared pre-and postgame measurements and measurements made at the beginning and end of the season. Results: Supraspinatus, forward flexion strength, and external rotation strength in abduction decreased significantly postgame compared to pregame. Pregame pain and fatigue increased with a greater number of games pitched during the season. Forward flexion, supraspinatus, and external rotation strength decreased with increasing number of games pitched during the season. Conclusions: Fast-pitch softball pitchers experience increased pain and fatigue during a single game and over the entire season. The increase in fatigue may predispose the player to injury. Further studies are needed to understand the relationship of pain and fatigue with predisposition to injury.

Neuroma management is an unresolved problem. Biomaterials to limit unwanted axonal growth could be a tool to manage neuroma. Hyaluronic acid/carboxymethyl cellulose (HA/CMC) is an antiadhesive, biodegradable material that is nontoxic to nerve. The purpose of this study was to evaluate the efficacy of this biomaterial to limit axonal growth. Rats received a sciatic nerve transection and repair with a short conduit (5 mm) containing HA/CMC, fibrin, or nothing (empty conduit). In another study, nerve was transected and either left undisturbed or wrapped with HA/CMC around the proximal and distal ends. In a final study, nerve was transected and repaired with an HA/CMC wrap. Four weeks following the procedures, nerves were harvested and assessed using histomorphometry to measure axonal regeneration. Axonal regeneration following transection was significantly inhibited by direct axonal contact with HA/CMC, whether within a conduit or wrapped around the transected proximal nerve end. Axonal regeneration following epineurial repair was not affected by HA/CMC wrapped around nerve, demonstrating axonal growth inhibition due to direct contact of regenerating axons with HA/CMC. These studies demonstrate the efficacy of HA/CMC to limit axonal outgrowth by contact with regenerating axons. HA/CMC barriers may prove to be a tool to prevent neuroma formation by inhibiting axonal growth. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 568-574, 2017.