Abstract
BACKGROUND: Deep medial collateral ligament (dMCL) injuries are a known cause of medial knee pain, which can result from either trauma or degenerative conditions. While conservative management, including bracing and physical therapy, remains the first-line treatment, persistent symptoms may necessitate additional interventions. Platelet-rich plasma (PRP) therapy has emerged as a promising treatment modality due to its ability to enhance ligament healing by promoting collagen synthesis and tissue regeneration. Recent studies highlight PRP's potential to improve pain and function in patients with medial collateral ligament injuries, particularly when guided by ultrasound for precise delivery. INDICATIONS/TECHNIQUE DESCRIPTION: This study presents 2 cases of dMCL injury with different causes. The first case involves a 25-year-old male athlete with a traumatic valgus injury, while the second case is a 63-year-old man with nontraumatic medial knee pain and underlying degenerative changes. Both patients underwent ultrasound-guided PRP injections after not responding to conservative management. The PRP preparation involved centrifugation of autologous blood to obtain leukocyte-rich PRP, which was then injected into the meniscotibial ligament (MTL) under ultrasound guidance. The injection was performed using a high-frequency linear transducer to visualize the dMCL and guide the needle precisely into the injured area of the MTL. The in-plane approach ensured optimal placement, minimizing the risk of inadvertent tissue damage. RESULTS: Both patients demonstrated significant pain reduction and functional improvement within 4 weeks postinjection. The athlete successfully returned to football, and the older patient resumed brisk walking without discomfort. Follow-up showed no recurrence of symptoms. Key considerations for PRP therapy include careful patient selection, individualization of PRP therapy, familiarity with the different PRP preparation systems, and proper patient education for managing expectations regarding treatment outcomes. Technical proficiency in ultrasound-guided injections is essential for accurate PRP delivery, minimizing procedural errors, and maximizing therapeutic benefits. DISCUSSION/CONCLUSION: dMCL injuries can cause persistent medial knee pain that is unresponsive to conservative treatment. PRP therapy presents a promising option for promoting ligament healing, with ultrasound guidance improving precision and potentially optimizing outcomes. However, further research is needed to establish standardized protocols for PRP formulation, dosing, and long-term efficacy. PATIENT CONSENT DISCLOSURE STATEMENT: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.