In a new study from Japan , the standard cortisone used for shoulder rotator cuff injections triamcinolone acetonide (TA) caused damage to tendons after application. Platelet rich plasma (PRP) was applied along with the steroid (TA) and it reversed the cellular damage to the rotator cuff tendon. The cortisone demonstrated negative effects on the tendon with cell death (apoptosis) lasting 3 weeks following administration. This suggests that repeated injections should wait at least 3 weeks, however in general we utilize cortisone shots sparingly to avoid cell death & more tearing. This evidence suggests that PRP could be potentially added when a cortisones shot is one of the only options to reduce pain. The combination of cortisone & PRP may be a strong anti-inflammatory agent and adding the prp may further protect the tendon from damaging side effects of cortisone. More research is needed.