Virginia Research Day 2021

Medical Resident Research Case Reports

28 Platelet Rich Plasma Therapy for a Latissimus Dorsi Muscle Tear in a Baseball Player

C. Pupke; O. Agaja; B. McCrady Corresponding author: oagaja@vt.vcom.edu

Via College of Osteopathic Medicine – Virginia Campus

Objective: The goal of this case report is to detail the unique presentation, thorough workup, and treatment strategy of a latissimus dorsi tear in a 17-year-old male baseball pitcher. Context: Latissimus dorsi tears are uncommon injuries and mainly occur in high-level athletes, with the highest frequency occurring in baseball pitchers. Diagnosis of a latissimus dorsi tear can be challenging, and thus the clinician must have a high index of suspicion for this injury. Imaging is essential in the diagnosis of a latissimus dorsi tear and should include a shoulder x-ray series in addition to an MRI of the shoulder. The MRI of the shoulder can be used to classify the severity of the latissimus dorsi tear as determined by the degree of muscle retraction. The approach to treatment can be divided into two categories: operative and non-operative treatment. Non-operative treatment options include but are not limited to rest, anti-inflammatory medications, and regenerative medicine procedures such as platelet- rich plasma (PRP) injections. Studies have shown that

PRP injections can accelerate the healing process of muscle and tendon injuries, as well as provide significant symptom improvement and pain reduction. Case Report Summary: A 17-year old male baseball pitcher presented to clinic with right shoulder pain that started 16 months ago in April of 2019 prior to initial evaluation in clinic. He could not recall a specific inciting injury; however, he does note that he felt a pull in his shoulder while pitching. He underwent physical therapy for his right shoulder prior to his initial visit and he reports no significant improvement of his symptoms. He also obtained an MRI of the right shoulder prior to the visit. The results demonstrated a grade 4 full-thickness tear of the latissimus dorsi at the myotendinous junction with 3-4 cm retraction at the insertion on the humerus. Treatment options were discussed with the patient. He agreed to undergo nonoperative treatment with PRP injection into his latissimus dorsi with ultrasound guidance. He followed up on 11/04 after going through PT directed throwing progression. Released to resume throwing

as tolerated. Will begin baseball workouts in Jan.

Data Sources and Overall Comparisons: The articles for this literature review were gathered from database searches on PubMed, Sage Journals, Wiley Online Library, and the online VCOM Library Catalog using the following keywords: ‘latissimus dorsi’, ‘muscle’ ‘tear’, and ‘platelet-rich plasma.’ Conclusion: Latissimus dorsi tears can cause significant shoulder and arm dysfunction, especially in baseball pitchers. This can result in reduced pitching velocity and accuracy. Management of these injuries can include PRP injections, which can stimulate the healing factors in the area of muscle injury. Although, PRP injections in latissimus dorsi tears have not been extensively studied, research has shown that a series of PRP injections in an athlete with a muscle rupture of his adductor longus muscle, coupled with rehabilitation, accelerated return to competition and provided significant pain relief.

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