Corticosteroid (CS) injection is commonly used in partial-thickness rotator cuff tears to decrease pain. However, unwanted side effects, such as tendon rupture, could result. Alternatively, platelet-rich plasma (PRP) injection is frequently used to treat tendinopathies because it enhances healing. This study compared the differences in tear size and functional scores between intralesional PRP and subacromial CS injections.
Patients with symptomatic partial-thickness tears of the supraspinatus tendon who underwent conservative treatment for more than 3 months were enrolled. All patients underwent magnetic resonance imaging (MRI) to confirm the diagnosis. Fourteen and 15 patients received intralesional PRP and subacromial CS injections, respectively. Tears were measured in the coronal and sagittal planes. The patients underwent another MRI 6 months after the injection. Tear size was compared between the two MRI results. The American Shoulder and Elbow Surgeons Shoulder score and the Constant-Murley score were also obtained.
The demographic data were similar between the two groups. In the coronal plane, PRP and CS showed significant tear size reductions of 3.39 mm and 1.10 mm, respectively. In the sagittal plane, PRP and CS showed tear size reductions of 2.97 mm and 0.76 mm, respectively. Functional scores improved 6 months after injection in both groups, but PRP showed better functional scores than CS.
Intralesional PRP injection can reduce the tear size in partial-thickness tears of the supraspinatus tendon. Subacromial steroid injection did not affect the tear size. While CS improved functional scores compared to baseline, PRP resulted in better improvement at 6 months post-injection.