Healing of partial tear of the supraspinatus tendon after atelocollagen injection confirmed by MRI: A case report

Rationale:Recently, collagen therapy has been made available for treating rotator cuff tendon injuries. However, to our knowledge, there are no clinical studies objectively investigating the effect of collagen therapy.Patient concerns:A 53-year-old female patient visited our pain clinic because of pain in the right shoulder. Although she had never experienced trauma and had not overused her shoulder and arm, the patient showed limited range of motion with painful arc syndrome. Moreover, the Neer test and Hawkins-Kennedy test were positive with subacromial tenderness.Diagnoses:The MRI findings revealed partial tears on the articular surface of the anterior supraspinatus tendon in the rotator cuff.Interventions:The patient was treated with injections of exogenous collagen at the site of the partial tear under ultrasound guidance.Outcomes:Follow-up MRI after injection of collagen revealed healing of the previous partial rupture of the tendon without any complications. Moreover, the patient reported reduction in pain and improvement in the movement of her shoulder during the follow-up period.Lessons:In this report, we demonstrate healing of a partial tear of the supraspinatus tendon in the rotator cuff after injection of exogenous collagen, as confirmed by MRI.