Platelet-rich Plasma, Corticosteroid, or Lidocaine for Acromioclavicular Joint Pain

Inclusion Criteria: * TRICARE eligible beneficiaries (active duty, dependents, and military retired) with a primary complaint of AC joint pain. * Age 18-65 years * Able to speak and read English well enough to provide informed consent, follow study instructions and independently answer the questionnaires/surveys. * Tender to palpation over the AC joint that reproduces the specific pain they are seeking care for * Provocative test (cross-arm test, pain with push-ups, etc) that reproduces the specific pain they are here to seek care for Exclusion Criteria: * In the last year, the subject received any invasive interventions including injections (corticosteroid, hyaluronic acid, lidocaine, PRP, etc.) or surgery for the affected shoulder - specifically to the AC joint. * Anyone separating from the military within 10 months (other than normal military retirement), pending a medical evaluation board, discharge from the military for medical reasons, or pending or undergoing any litigation for an injury * AC Joint separation that are with a severity of Grades III-VI (in most cases, these are treated surgically, although 78% of military surgeons recommended preferring conservative care for Grade III separations, and 86% recommending at least 3 months of conservative care before surgical consideration. * Systemic Disease that could otherwise be responsible for the shoulder pain (i.e. rheumatoid arthritis, gout, or psoriatic arthritis), non-musculoskeletal conditions causing shoulder …