Marc Darrow, MD, JD
“My mother is 89 and has bone-on-bone arthritis in her right shoulder. She takes tramadol and acetaminophen. Her orthopedic surgeon has suggested reverse shoulder replacement. Could PRP or stem-cell therapy be a viable option?”
A nonsurgical injection may be worth discussing for symptom relief in selected patients, particularly when surgery is undesirable or medically unsuitable. However, neither PRP nor a cell-based injection has been shown to reliably restore the cartilage of a bone-on-bone shoulder. The evidence also does not establish that either provides results equivalent to reverse shoulder replacement in an 89-year-old.
That distinction matters because the family’s goal may be better sleep, easier dressing, or less reliance on pain medication rather than a return to strenuous activity. An evaluation should consider whether a less invasive treatment has a reasonable chance of meeting those goals and what surgery might offer if symptoms remain severe.
Age alone should not decide the answer. Her overall health, frailty, independence, shoulder anatomy, preferences, and available support are central to the decision.
What does bone-on-bone mean in the shoulder?
The phrase usually describes advanced loss of joint space on an X-ray, reflecting substantial cartilage loss in the ball-and-socket, or glenohumeral, joint. It identifies serious structural disease, but it does not measure pain or establish that all symptoms come from that joint.
The rotator cuff, biceps tendon, bursae, acromioclavicular joint, and cervical spine may contribute to shoulder-region symptoms. At the same time, advanced arthritis that matches restricted motion and disabling joint pain can be a convincing explanation. The purpose of examination is to clarify the contribution of each finding, rather than dismiss an abnormal X-ray.
For this mother, the practical questions include what movement remains, whether sleep is disrupted, whether she can dress and wash, and whether the right arm is needed to use a walker or push up from a chair. Those demands affect both treatment goals and recovery planning.
Why might reverse shoulder replacement be recommended?
An anatomic replacement reproduces the ball-and-socket arrangement and generally depends on a functioning rotator cuff. A reverse replacement changes the joint mechanics so the deltoid can contribute more effectively to arm elevation.
A reverse implant may be proposed when the cuff is deficient, there is cuff-tear arthropathy, or bone loss and joint anatomy make it suitable. Its use has also expanded to selected patients with primary shoulder arthritis. A 2024 review describes the role of reverse replacement in glenohumeral arthritis, including shoulders with substantial glenoid bone loss. (1)
The recommendation does not establish that the cuff is torn in this particular patient. The family should ask why reverse rather than anatomic replacement was selected and which structural problem it is intended to address.
An injection cannot reproduce the mechanical reconstruction of a reverse implant. It may still have value if symptom reduction is an acceptable goal, but that is a different proposed outcome.
What evidence supports PRP for shoulder arthritis?
PRP is prepared from the patient’s blood and contains concentrated platelets. It is not a stem-cell preparation. Research on PRP for knee arthritis or a rotator cuff tendon cannot automatically be transferred to advanced glenohumeral arthritis.
A randomized, double-blind trial studied 70 patients receiving a single ultrasound-guided injection of either leukocyte-poor PRP or hyaluronic acid. Both groups improved in pain and function over follow-up, with no significant difference between them through 12 months. Improvements were reported across arthritis severities. (2)
These findings support discussing possible symptom benefit. They do not establish superiority over placebo because the trial did not include a placebo group. They also do not establish cartilage regeneration, reliable avoidance of replacement, or a predictable response for an 89-year-old.
A useful PRP discussion therefore identifies the goal and acknowledges the possibility of no meaningful benefit. It should not promise that bone-on-bone arthritis will be reversed or that a fixed series of injections will eliminate surgery.
What about bone marrow or stem-cell treatment?
Bone marrow aspirate contains a mixture of cells and other components. Bone marrow aspirate concentrate is processed to change the concentration of those components. Neither is a purified population of cells grown in a laboratory, and the terms should not be used interchangeably when describing research.
A pilot randomized trial compared nonconcentrated marrow aspirate with cortisone for shoulder osteoarthritis. Twenty-two patients, representing 25 shoulders, completed the baseline and 12-month outcome assessments. Some secondary outcomes favored marrow, but the primary shoulder-specific outcome did not show a statistically significant difference between groups. The trial ended early and was too small for firm conclusions. Importantly for this family, eligibility was limited to ages 18–75. (3)
That trial does not establish a result for an 89-year-old, and it should not be presented as proof that concentrated marrow is superior to PRP. Marrow collection also adds a harvesting procedure and its discomfort and risks.
A 2026 narrative review found no published randomized trial directly comparing PRP with BMAC for a shoulder disorder. It described shoulder BMAC evidence as sparse and emphasized the need for standardized, shoulder-specific trials. (4)
For this patient, a more invasive preparation should have a clear rationale. A claim that older age automatically rules treatment out, or that a higher cell count guarantees success, would go beyond the available evidence.
Can someone near 90 benefit from reverse replacement?
Selected older patients can benefit, but favorable reports need to be interpreted with their limitations.
A study published in a 2026 journal issue followed 13 patients aged at least 90 who underwent reverse replacement. Motion improved substantially, and all eventually returned to their previous living arrangements. However, approximately half initially required a rehabilitation facility. The series included cuff-tear arthropathy and fractures, rather than a uniform group with primary arthritis. It was small and retrospective, so it cannot establish safety for every person near that age. (6)
A larger national inpatient database study included 555 patients aged 90–99. Compared with younger patients, they had longer hospital stays and more medical complications. Elective procedures had fewer complications than nonelective procedures. The study highlights the importance of careful selection and preparation rather than treating age as either a guarantee of danger or a guarantee of safety. (7)
Neither study supplies this mother’s personal risk. That requires assessment of medical conditions, frailty, cognition, balance, nutrition, and the help available during recovery. If she relies on the arm for transfers or a walking aid, the surgeon and rehabilitation team need to address that explicitly.
Tramadol and acetaminophen need review in the overall plan
Taking these medications does not automatically determine eligibility for PRP, marrow treatment, or surgery. It does indicate that pain remains significant enough to require ongoing treatment.
At age 89, the prescriber should review benefit alongside sedation, confusion, constipation, falls, kidney or liver disease, and medication interactions. The family should also check whether any combination product contains additional acetaminophen so the total amount is understood. Doses and medication changes should be reviewed with her clinician rather than altered based on an article.
Other medicines, including blood thinners, need to be disclosed before any procedure. They should not be stopped independently to prepare for an injection.
References
1 Hays C. Current Role of Reverse Total Shoulder Arthroplasty in the Management of Glenohumeral Osteoarthritis. Orthop Clin North Am. 2024;55(4):489-502. doi:10.1016/j.ocl.2024.05.001.
2 Kirschner JS, Cheng J, Creighton A, Santiago K, Hurwitz N, Dundas M, Beatty N, Kingsbury D, Konin G, Abutalib Z, Chang R. Efficacy of Ultrasound-Guided Glenohumeral Joint Injections of Leukocyte-Poor Platelet-Rich Plasma Versus Hyaluronic Acid in the Treatment of Glenohumeral Osteoarthritis: A Randomized, Double-Blind Controlled Trial. Clin J Sport Med. 2022;32(6):558-566. doi:10.1097/jsm.0000000000001029.
3 Dwyer T, Hoit G, Lee A, Watkins E, Henry P, Leroux T, Veillette C, Theodoropoulos J, Ogilvie-Harris D, Chahal J. Injection of Bone Marrow Aspirate for Glenohumeral Joint Osteoarthritis: A Pilot Randomized Control Trial. Arthrosc Sports Med Rehabil. 2021;3(5):e1431-e1440. doi:10.1016/j.asmr.2021.07.005.
4 Jung CH, Choi SY, Lee DH. Biologic Injection Therapy for Shoulder Disorders: A Narrative Review Comparing Platelet-Rich Plasma and Bone Marrow Aspirate Concentrate. Medicina (Kaunas). 2026;62(8):1541. doi:10.3390/medicina62081541.
5 U.S. Food and Drug Administration. Important Patient and Consumer Information About Regenerative Medicine Therapies. FDA consumer guidance. Accessed October 29, 2026.
6 Obana KK, Weiss DL, Luzzi AJ, LeVasseur MR, Knudsen ML, Jobin CM, Levine WN. Reverse total shoulder arthroplasty is safe and effective in patients ≥90 Years old. JSES Int. 2026;10(1):101374. doi:10.1016/j.jseint.2025.08.011.
7 Toutoungy M, Venishetty N, Mounasamy V, Khazzam M, Sambandam S. Reverse Shoulder Arthroplasty in Nonagenarians – NIS-based study of perioperative and postoperative complications. J Orthop. 2023;42:40-44. doi:10.1016/j.jor.2023.07.003.
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