Serratus Anterior Muscle Injury in an Overhead-Throwing Athlete: A Report of a Rare Case With Serial Ultrasonographic Observations.

Serratus anterior muscle injuries in overhead athletes are extremely rare, and no consensus exists regarding treatment strategies or return-to-play timelines. We report the case of a high school baseball pitcher who sustained a serratus anterior injury. Ultrasonography revealed swelling and a hypoechoic area in the lower fibers of the serratus anterior at the level of the seventh and eighth ribs. Based on these findings, conservative management with localized compression was initiated, without the use of any medications, including nonsteroidal anti-inflammatory drugs. Serial ultrasonographic monitoring confirmed resolution of the inflammatory findings, after which contraction and stretching exercises were introduced. A progressive increase in throwing intensity enabled a return to competition 32 days post-injury. No reinjury occurred, and competitive play was maintained for six months. This case demonstrates that ultrasonographic monitoring is useful for guiding the progression of conservative therapy and determining the appropriate timing for return to play in serratus anterior injuries, providing clinically relevant insight into this rare throwing-related shoulder pathology.