Thomas Wright, MD
Read complete study: Risk of insufficient internal rotation after bilateral reverse shoulder arthroplasty: clinical and patient reported outcome in 57 patients.
This study focused on the effects and risks of bilateral reverse shoulder arthroplasty (rTSA) on internal rotation (IR) in 57 patients. Data was recorded up to two years after the second surgery. The study found that only 15 percent of patients had insufficient IR in both shoulders after 12 months and 5 percent after 24 months. Patients who had insufficient baseline IR in their second shoulder and insufficient IR 12 month post op after their first shoulder had a 100 percent risk of having insufficient IR in both shoulders. The conclusion of this article is a recommendation to use staged bilateral rTSA over the use of a hemiathroplasty. The authors found that the majority of patients would undergo the surgery again, as it does provide benefits, like reduction in pain, regardless of the issues with IR.
Literature Review:
The authors of this study focused on the risks of staged bilateral rTSA on internal rotation. I agree with their concern, as bilateral decreased IR could result in difficulties with toileting. In my practice, I stage my bilateral cases; however the timing is up to the patient. I will proceed with the second surgery no sooner than 12 weeks, but I do not recommend waiting as long as a year. In 2014, we published an article on bilateral rTSA1 in which we found all patients eventually had enough IR to allow toileting with at least one shoulder. I agree with the authors and do not recommend using a hemiarthroplasty in the second shoulder, based on the positive results that we had with rTSA.
Although the article showed a 100 percent failure rate in achieving sufficient IR in the second shoulder when it comes to patients who have both insufficient baseline IR and insufficient IR 12 months post op in their first shoulder, we have not noted that to be a problem.
One example is a 79 year old male with symptomatic cuff tear arthropathy on the right and a failed total shoulder arthroplasty (TSA) on the left due to rotator cuff insufficiency.Because of the predictable nature of performing an rTSA as a primary, the right side was addressed first. At three months post-op he had IR to L5.
At four months post-op, he elected to have a revision of the failed TSA on the left. This required explantation of the stem—because the stem was not a platform stem—and allograft structural bone graft to the glenoid defect after removal of the prosthetic glenoid. At six months follow-up, he had IR to S1 on the revision side.
At two years follow-up on both sides, he was very satisfied and had no trouble with activities of daily living.
IR with rTSA is generally limited, but only slightly more than with a TSA; in our series, the IR was limited by only one or two anatomic levels. In the rare cases when a patient can get their hand up to the mid-thoracic level, the patient is always female. If I am concerned about IR in the second operative shoulder, —for instance, in cases of insufficient baseline internal rotation in the second shoulder and post op in the first shoulder— I have found success in treating the second shoulder with less humeral retroversion (approximately 10⁰ as opposed to 20-30⁰ in most of our shoulders). Although the article showed a 100 percent failure rate in achieving sufficient IR in the second shoulder when it comes to patients who have both insufficient baseline IR and insufficient IR 12 months post op in their first shoulder, we have not noted that to be a problem. For some reason the patient figures it out. The trade-off for limited IR with the rTSA is improved function, pain relief and patient satisfaction.
In summary, we do not shy away from performing bilateral rTSA at time intervals chosen by the patient. Before the surgery, we do discuss the issue of IR limitations, but I have never had a patient cancel surgery over that concern.
Thomas Wright, MD specializes in the upper extremity at University of Florida College of Medicine. He completed his residency at University of Florida and his fellowship in hand and upper extremity surgery at Mayo Clinic. One of the original Equinoxe design team members and world renowned expert in shoulder surgery, Dr. Wright has earned 13 grants and refereed more than 110 published works, among many other accomplishments.
References
- Stevens CG, Struk AM, Wright TW. The functional impact of bilateral reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2014 Sep;23(9):1341-8. doi: 10.1016/j.jse.2013.12.012. Epub 2014 Feb 26. PMID:24581874