Grand Rapids Shoulder

You mean that I don’t need to go to physical therapy after my reverse shoulder replacement?
How will I gain motion and strength?

I am a big believer in the potential benefit of physical therapy and an exercise program. I am addicted to exercise, and recognize the benefits of regular physical exertion. It helps the mind and they body, and is an essential part of being a healthy person. As laid out in a prior post, I also believe that physical therapy, time, and some exercise can lead to resolution of many shoulder problems. However, I rarely consider formal physical therapy to be helpful in the recovery process of reverse arthroplasty. In fact, I consider formal physical therapy a risk in this situation.

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What are the risks?

Reverse shoulder replacement is one of the most predictable and beneficial interventions to offer patients for a growing number of indications. Complications do occur – fortunately they have become much less frequent as surgeons have gained experience and designs have improved. Shortly after their introduction into the US in 2004, the groundbreaking surgeon Dr. Charles Rockwood declared the implant “a terrible prothesis”, and that “surgeons should not be using it.” (spoken in a strong Texas accent). Partly due to concern of complication, in my fellowship training at the University of Washington in 2004 under the direction of Dr. Rick Matsen and Dr. Kevin Smith, I observed only 3 or 4 of these devices utilized in an entire year of two very busy shoulder surgery practices. Fortunately, complication rates have diminished, and now approach complication rates of the more experienced anatomic shoulder replacement. Registry data out of New Zealand and Australia describe higher revision rates of anatomic implants as compared with reverse implants – this is partly why 70-80% of implants utilized these days are of the reverse design.

However, despite it’s relative recent success, problems with Reverse Arthroplasty still occur. The top 2 problems seen after reverse replacement include ACROMIAL FRACTURE and INSTABILITY. I consider these problems to lie on opposite ends of a potential spectrum of problems, but that discussion is for another day. Both may occur due to issues with activity and use of the arm, especially shortly after surgery. I focus on acromial fracture here, as this seems to be the potentially more debilitating problem.

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Acromial Fracture

Acromial fracture is seen in 3-5% of cases.¹ It can be a devastating problem. Surgical attempts at repair are unpredictable, and the development of fracture greatly diminishes the outcome of the procedure both in terms of function as well as in comfort. These shoulders have more pain in the long term, and they often will not see elevation of the arm above shoulder level (90 degrees of forward elevation).²

These fractures have gathered much attention, and surgeons now employ the reliable Levy classification system to describe the injury.³

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Risk Factors

Risk factors have been outlined – they include the presence of osteoporosis, female gender, and severe cuff arthropathy.⁴ Screw position has also been linked to acromial fracture. Specifically, a superior screw in the baseplate can act as a stress riser to initiate fracture.⁵

Other potential risks include overlengthening the arm, or overlateralizing the COR (which decreases the deltoid lever arm). These factors remain elusive and objective numbers are not available to guide surgical decisions about implant selection and positioning.

Surgical attempts at fixation are unpredictable.⁶ Hardware failure and nonunion are common. As such, most shoulder surgeons routinely recommend nonoperative care for these injuries. Industry and their consulting surgeons are working on custom plates for these fractures that span the length of the scapular spine, and employ hook constructs around both ends to help stabilize the bone. It remains to be seen if this will improve results – anecdotal early results are promising.

It seems that the current best treatment for post-operative acromial fracture after reverse arthroplasty is avoiding fracture.

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Literature on Formal PT and Reverse Shoulder

Anecdotally, many of the fractures that I see occur in the first 3 months after surgery. The literature describes that most will occur in the first 9-12 months after surgery. Late fractures also occur.

Avoiding early formal physical may play a significant role in avoiding this problem. Several papers have been published which describe success with this approach.

A recent prospective study compared formal therapy to a simple home based stretching program and found essentially equivalent outcomes in range of motion.⁷

Another randomized, clinical trial did not show any advantage of formal physical therapy over a simple home based program that focused on early stretching and avoiding strengthening for 3 months.⁸

Finally, data has been published describing the link between early formal physical therapy in the presence of osteoporosis and an increased risk of fracture.⁹

It seems prudent to at least delay formal therapy to allow a period of time for remodeling of the bone and accommodation of the new stresses that are seen by the acromion and scapular spine. Allow Wolff’s Law to work. I personally recommend avoiding formal strengthening for at least 4-6 months following reverse arthroplasty. Most patients are doing quite well at that point in recovery, and have no interest in beginning formal physical therapy.

A link to my protocol is included here:

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Summary

Acromial fracture after reverse arthroplasty can happen in around 5% of patients. It can have a fairly significant impact on the outcome of the procedure. Risks include osteoporosis, female gender, significant cuff arthropathy, and some other implant related factors that we are beginning to understand. Surgery has been unreliable in treating them. Our current best treatment is to simply avoid them in the first place. One key piece might be avoiding formal PT, or at least delaying strengthening until Wolff’s Law can remodel the bone of the scapula.

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References

1. Cho CH, Rhee YG, Yoo JC, Ji JH, Kim DS, Kim YS, Rhee SM, Kim DH. Incidence and risk factors of acromial fracture following reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2021 Jan;30(1):57-64. doi: 10.1016/j.jse.2020.04.031. Epub 2020 Jun 9. PMID: 32807375. ↩︎
2. Cui H, Cheong J, McKenzie D, Gould D, Rele S, Patel M. Outcomes of conservative treatment of acromial and scapular spine stress fracture post reverse shoulder arthroplasty: a systematic review with meta-analysis. J Shoulder Elbow Surg. 2023 Dec;32(12):2613-2630. doi: 10.1016/j.jse.2023.07.011. PMID: 37573934. ↩︎
3. Levy JC, Anderson C, Samson A. Classification of postoperative acromial fractures following reverse shoulder arthroplasty. J Bone Joint Surg Am. 2013 Aug 7;95(15):e104. doi: 10.2106/JBJS.K.01516. PMID: 23925750. ↩︎
4. ASES Complications of RSA Research Group:; Mahendraraj KA, Abboud J, Armstrong A, Austin L, Brolin T, Entezari V, Friedman L, Garrigues GE, Grawe B, Gulotta L, Gutman M, Hart PA, Hobgood R, Horneff JG, Iannotti J, Khazzam M, King J, Kloby MA, Knack M, Levy J, Murthi A, Namdari S, Okeke L, Otto R, Parsell DE, Polisetty T, Ponnuru P, Ricchetti E, Tashjian R, Throckmorton T, Townsend C, Wright M, Wright T, Zimmer Z, Menendez ME, Jawa A. Predictors of acromial and scapular stress fracture after reverse shoulder arthroplasty: a study by the ASES Complications of RSA Multicenter Research Group. J Shoulder Elbow Surg. 2021 Oct;30(10):2296-2305. doi: 10.1016/j.jse.2021.02.008. Epub 2021 Mar 4. PMID: 33677115. ↩︎
5. Galvin JW, Eichinger JK, Li X, Parada SA. Scapular Fractures After Reverse Shoulder Arthroplasty. J Am Acad Orthop Surg. 2022 Mar 1;30(5):e517-e527. doi: 10.5435/JAAOS-D-20-01205. PMID: 35050935. ↩︎
6. ASES Complications of RSA Research Group:; Mahendraraj KA, Abboud J, Armstrong A, Austin L, Brolin T, Entezari V, Friedman L, Garrigues GE, Grawe B, Gulotta L, Gutman M, Hart PA, Hobgood R, Horneff JG, Iannotti J, Khazzam M, King J, Kloby MA, Knack M, Levy J, Murthi A, Namdari S, Okeke L, Otto R, Parsell DE, Polisetty T, Ponnuru P, Ricchetti E, Tashjian R, Throckmorton T, Townsend C, Wright M, Wright T, Zimmer Z, Menendez ME, Jawa A. Predictors of acromial and scapular stress fracture after reverse shoulder arthroplasty: a study by the ASES Complications of RSA Multicenter Research Group. J Shoulder Elbow Surg. 2021 Oct;30(10):2296-2305. doi: 10.1016/j.jse.2021.02.008. Epub 2021 Mar 4. PMID: 33677115. ↩︎
7. Schick S, Elphingstone J, Paul K, He JK, Arguello A, Catoe B, Roberson T, Momaya A, Brabston E, Ponce B. Home-based physical therapy results in similar outcomes to formal outpatient physical therapy after reverse total shoulder arthroplasty: a randomized controlled trial. J Shoulder Elbow Surg. 2023 Aug;32(8):1555-1561. doi: 10.1016/j.jse.2023.03.023. Epub 2023 May 11. PMID: 37178958. ↩︎
8. Chalmers PN, Tashjian RZ, Keener JD, Sefko JA, Da Silva A, Morrissey C, Presson AP, Zhang C, Chamberlain AM. Active physical therapy does not improve outcomes after reverse total shoulder arthroplasty: a multi-center, randomized clinical trial. J Shoulder Elbow Surg. 2023 Apr;32(4):760-770. doi: 10.1016/j.jse.2022.12.011. Epub 2023 Jan 21. PMID: 36690173. ↩︎
9. Su F, Kucirek N, Goldberg D, Feeley BT, Ma CB, Lansdown DA. Incidence, risk factors, and complications of acromial stress fractures after reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2024 Jan;33(1):65-72. doi: 10.1016/j.jse.2023.06.008. Epub 2023 Jul 14. PMID: 37454923. ↩︎