For overhead athletes, elbow ulnar collateral ligament (UCL) insufficiency is a potential career-ending injury. Baseball players with UCL insufficiency typically complain of medial-sided elbow pain that affects their ability to throw. Loss of velocity, loss of control, difficulty warming up, and pain while throwing are all symptoms of UCL injury.
Classically, nonoperative treatment of UCL injuries involves activity modification, use of anti-inflammatory medication, and a structured physical therapy program. Asymptomatic players can return to throwing after a structured interval throwing program. Rettig and colleagues1 found a 42% rate of success in conservatively treating UCL injuries in throwing athletes. UCL reconstruction is reserved for players with complete tears of the UCL or with partial tears after failed conservative treatment. Several techniques have been used to reconstruct the ligament, but successful outcomes depend on a long rehabilitation process. According to most published series, 85% to 90% of athletes who had UCL reconstruction returned to their previous level of play, but it took, on average, 9 to 12 months.2,3 This prolonged recovery period is one reason that some older professional baseball players, as well as casual high school and college players, elect to forgo surgery.
Over the past few years, platelet-rich plasma (PRP) has garnered attention as a bridge between conservative treatment and surgery. PRP refers to a sample of autologous blood that contains a platelet concentration higher than baseline levels. This sample often has a 3 to 5 times increase in growth factor concentration.4-6 Initial studies focused on its ability to successfully treat lateral epicondylitis.7-9 More recent clinical work has shown that PRP can potentially enhance healing after anterior cruciate ligament reconstruction,10-14 rotator cuff repair,15-17 and subacromial decompression.11,18-23 If PRP could be used to successfully treat UCL insufficiency that is refractory to conservative treatment, then year-long recovery periods could be avoided. This could potentially prolong certain athletes’ careers or, at the very least, allow them to return to play much sooner. In the present case series, we hypothesized that PRP injections could be used to successfully treat partial UCL tears in high-level throwing athletes, obviating the need for surgery and its associated prolonged recovery period.
Materials and Methods
Institutional Review Board approval was obtained for this retrospective study of 44 baseball players treated with PRP injections for partial-thickness UCL tears.
Patients provided written informed consent. They were diagnosed with UCL insufficiency by physical examination, and findings were confirmed by magnetic resonance imaging (MRI). After diagnosis, all throwers underwent a trial of conservative treatment that included rest, activity modification, use of anti-inflammatory medication, and physical therapy followed by an attempt to return to throwing using an interval throwing program.
Study inclusion criteria were physical examinations and MRI results consistent with UCL insufficiency, and failure of the conservative treatment plan described.
Patients were injected using the Autologous Conditioned Plasma system (Arthrex). PRP solutions were prepared according to manufacturer guidelines. After the elbow was prepared sterilely, the UCL was injected at the location of the tear. Typically, 3 mL of PRP was injected into the elbow. Sixteen patients had 1 injection, 6 had 2, and 22 had 3. Repeat injections were considered for recalcitrant pain after 3 weeks.
After injection, patients used acetaminophen and ice for pain control. Anti-inflammatory medications were avoided for a minimum of 2 weeks after injection. Typical postinjection therapy protocol consisted of rest followed by progressive stretching and strengthening for about 4 to 6 weeks before the start of an interval throwing program. Although there is no well-defined postinjection recovery protocol, as a general rule rest was prescribed for the first 2 weeks, followed by a progressive stretching and strengthening program for the next month. Patients who were asymptomatic subjectively and clinically—negative moving valgus stress test, negative milking maneuver, no pain with valgus stress—were started on an interval throwing program.