ICL Debunks Urban Legends in Total Shoulder Arthroplasty

“Many of the things entrenched in our practice are thought to be based on science but in fact are more urban legend,” Richard J. Friedman, MD, FRCSC, chief of shoulder and elbow surgery and professor of orthopaedic surgery at the Medical University of South Carolina in Charleston, South Carolina, said in his introduction to the Instructional Course Lecture (ICL) titled “Urban Legends versus Evidence-Based Medicine in Total Shoulder Arthroplasty.” He went on to say, “Medicine should be integration of best evidence combined with our clinical experience and our patient’s unique values.”

Dr. Friedman was joined by a panel of experts to discuss pre-, intra-, and postoperative practices in total shoulder arthroplasty (TSA) to determine what is best practice based on evidence-based medicine. Alongside Dr. Friedman were Lawrence V. Gulotta, MD, FAAOS, chief of the shoulder and elbow division at Hospital for Special Surgery in New York City; Howard Routman, DO, FAAOS, president of Atlantis Orthopaedics in Florida; and Thomas (Quin) Throckmorton, MD, FAAOS, shoulder and elbow specialist at the Campbell Clinic in Germantown, Tennessee.

Preoperative facts versus fiction
According to Dr. Gulotta, evidence-based medicine guides surgeons in making the best medical decisions by utilizing information obtained from well-designed and well-conducted clinical studies. Certain urban legends persist in preoperative considerations for TSA, and Dr. Gulotta sorted through some of these truths and untruths.

One area where urban legends persist is preoperative considerations for patients. For instance, the notion that preoperative blood donation reduces the need for transfusion postoperatively is not supported by strong evidence. In fact, donating blood before surgery can have its own risks and should be carefully evaluated on a case-by-case basis. There is very little to no evidence that donating blood pre-TSA will reduce transfusion rate. Another example pertains to the use of tranexamic acid (TXA) before incision as a standard of care in shoulder arthroplasty. Although Dr. Gulotta acknowledged that this practice was previously considered an urban legend, he highlighted that it is now recognized as an evidence-based standard of care.

Obesity is another aspect that demands critical examination. Although BMI above 40 may lead to the cancellation of surgery and referral to weight-management specialists in certain cases, it is important to note that shoulder replacement surgery is not necessarily contraindicated solely based on obesity. Studies have shown that obesity may be a risk factor for instability, particularly after reverse shoulder replacement, but there is no evidence suggesting it significantly affects final outcomes.

Patients with uncontrolled diabetes are at higher risk of readmissions and wound complications and may be deemed unfit for elective shoulder replacement surgery. However, for patients with an A1C of 8 to 10, an endocrinologist can help weigh the pros and cons and explore ways to optimize glycemic control before surgery.

Intraoperative considerations
Sorting out the “intraoperative shoulder arthroplasty voodoo from evidence-based medicine,” Dr. Routman focused on the impact of lavage during TSA, specifically flow rate and pressure, and whether additives or wound treatments make a difference in the prevention of postoperative infection. “The impossible dream here is to think that we’re going to be able to have level one evidence that one specific variable is going to prevent infection,” he said. Infection after TSA is likely affected by a combination of factors, including type and amount of irrigation, time of operation, antibiotic powder application, skin preparation, wound dressing, and patient factors.

Dr. Routman discussed the use of antibiotic powders, specifically vancomycin, in surgical wounds. According to him, it is “reasonably safe and effective with some proven benefits in the spine literature, [though the] jury is out on arthroplasty benefit.” He also touched on the ineffectiveness of most skin preparations against Cutibacterium acnes, a bacterium associated with surgical-site infections. He suggested hydrogen peroxide as a potential solution, either through a preoperative regimen or directly at the time of surgery.

Last on his agenda was incision care. “This is a new area in shoulders where we’re starting to see people use not just silver-pregnant dressing, but also negative-pressure wound dressings. I think this has been a big change in my practice over the past 3 or 4 years,” he said. Incisional negative-pressure wound-therapy devices such as Prevena and PICO have limited evidence supporting their use, Dr. Routman mentioned, but they are safe for routine use if resources are available.

Dr. Friedman challenged a few misconceptions surrounding the use of drains, best wound-closure methods, and computer navigation during TSA. Another urban legend in TSA involves the “best” wound-closure method. For deep closure, barbed sutures take less time but result in similar outcomes and complication rates. Barbed sutures should be avoided in superficial closures, he noted. For superficial closures, Dr. Friedman explained, staples are faster and cheaper compared with sutures and glue, with similar outcomes and complication rates.

Claims of superior postoperative dressing options in TSA have been a topic of debate. Dr. Friedman discussed the benefits of hybrid fiber dressings over traditional dressings. Hybrid fiber dressings offer advantages such as higher exudate capacity and permeability, fewer dressing changes, lower blistering rates, and potentially reduced surgical-site infections. However, it is worth noting that silver-impregnated dressings (hydrofiber/hydrocolloid dressings) have shown superiority over traditional dressings in multiple studies for total hip and knee arthroplasty and may be an alternative dressing for shoulder arthroplasty.

Contrary to a prevalent urban legend in TSA that dismisses the significance of computer navigation, Dr. Friedman shed light on the advantages of incorporating 3D planning, computer navigation, and potentially patient-specific instrumentation. These measures were shown to enhance the positioning of the glenoid component. Although additional research is required to assess long-term clinical outcomes, these findings challenge the misconception that computer navigation has no impact on TSA.

Postoperative care
Last to take the stage was Dr. Throckmorton, who guided the attendees through the hearsay of TSA postoperative care, discussing venous thromboembolism (VTE) prophylaxis, sling use, and physical therapy (PT).

“VTE is rare, but it’s significant,” he said, before recommending mechanical prophylaxis due to its low risk. Routine chemoprophylaxis is not universally needed based on current evidence. Low-dose aspirin is effective and has a low complication rate. No evidence shows superiority of any chemoprophylaxis, and individual risk assessment should guide strategies to prevent VTE.

Dr. Throckmorton noted that many surgeons prefer sling use postoperatively and referenced a study comparing patients who were either placed in a neutral sling position or encouraged to maintain internal rotation. Surprisingly, the neutral sling position showed better outcomes in terms of reduced discomfort, improved rotation, and increased abduction compared to the traditional method.

Dr. Throckmorton posed the provocative question: “Is formal PT even needed?” The short answer, according to him, is complicated. A randomized, controlled trial in Archives of Physiotherapy found that a home-based therapy group had better outcomes, with no differences in patient satisfaction, compared with an outpatient rehabilitation group. Based on these findings, Dr. Throckmorton recommended informing patients that they can perform PT at home and achieve similar or better results while saving money at the same time.

The comprehensive review of TSA challenged prevailing urban legends, dispelling misconceptions and highlighting integration of the best available high-quality evidence with real clinical experience and patient values to optimize patient outcomes.

Cailin Conner is the associate editor of AAOS Now. She can be reached at cconner@aaos.org.

References

1. Baumgarten KM, Osborn R, Schweinle WE III, et al: The position of sling immobilization influences the outcomes of anatomic total shoulder arthroplasty: a randomized, single-blind, prospective study. J Shoulder Elbow Surg 2018;27(12):2120-8. doi:10.1016/j.jse.2018.08.030
2. Kennedy JS, Reinke EK, Friedman LGM, et al: Protocol for a multicenter, randomised controlled trial of surgeon-directed home therapy vs. outpatient rehabilitation by physical therapists for reverse total shoulder arthroplasty: the SHORT trial. Arch Physiother 2021;11(1):28. doi:10.1186/s40945-021-00121-2