Well, Steroid injection is out as it would promote tears, but platelet rich plasma (PRP) injections have been found to work as well:
Fitzpatrick, Jane, et al.
The Effectiveness of Platelet-Rich Plasma Injections in Gluteal Tendinopathy: A Randomized, Double-Blind Controlled Trial Comparing a Single Platelet-Rich Plasma Injection With a Single Corticosteroid Injection.
The American journal of sports medicine (2017): 0363546517745525.
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