Innovations in Shoulder Hemiarthroplasty: A New Era for Active Patients

Innovations in Shoulder Hemiarthroplasty

Shoulder joint arthritis has been treated with partial joint replacement surgery, also called hemiarthroplasty, for decades. Dr. Charles Neer, a pioneer of modern shoulder joint replacement surgery, first published on prosthetic shoulder replacement in 1955–relatively recent for medical history.1 The traditional shoulder hemiarthroplasty involved a long-stemmed humeral component and a metal humeral head (the ball of the shoulder) that would contact the remaining cartilage and bone on the glenoid (the socket of the shoulder). In the past, the stem was cemented in place with a PMMA cement to stabilize the stem. 

Many anatomic shoulder replacements also involve placement of a plastic liner for the socket; this is called in anatomic total shoulder replacement (TSA). Total shoulder arthroplasty or replacement is a very reliable surgery that can offer great results to patients with an intact rotator cuff. However, there can be complications that arise after TSA surgery.

For people participating in sports, heavy labor, and weight training, the TSA components can experience elevated forces on the joint. These stresses can lead to loosening of the glenoid component and/or wear of the polyethylene liner. Failure of the polyethylene liner is devastating for an otherwise well-functioning shoulder arthroplasty. The most common type of major complication for anatomic shoulder replacements has been shown in orthopedic research to be loosening of the glenoid component.2 Prevention of this problem is a priority for every anatomic shoulder replacement. Failed glenoid components typically require revision to hemiarthroplasty or reverse shoulder replacement (RSA). One of the ways to avoid this complication is to avoid placement of the polyethylene liner! This is called a hemiarthroplasty when only the “ball” of the shoulder is replaced.

Research has been performed on shoulder hemiarthroplasty surgery patients, demonstrating significant improvements in pain and function, but with a slower recovery and higher revision rates than TSA.3,4 While many patients had marked improvements in their shoulder function and pain with a traditional shoulder hemiarthroplasty, innovations in surgical technique, imaging, and materials science are facilitating additional opportunities for improving outcomes. These innovations had the practical goals of optimizing patient function, increasing implant longevity, and decreasing the likelihood of complications. 

Recent advancements led to the introduction of a new humeral head component that is available for shoulder hemiarthroplasty and ream and run candidates. One of these innovations is the introduction of a humeral head pyrocarbon component rather than a cobalt-chrome or titanium humeral head. The pyrocarbon humeral head component allows for a smooth range of motion of the shoulder with potential benefits over metal humeral head hemiarthroplasty. The pyrocarbon humeral head implant is 30 times smoother than a metal component,6 self-lubricating, and has a Young’s modulus closer to that of bone compared to cobalt-chrome metal. These implants have shown good longevity with medium-term follow-up in the literature.7  

Hemiarthroplasty of the ball of the shoulder can also be paired with biologic resurfacing of the socket of the shoulder (glenoid), driven by Dr. Frederick Matsen’s research. He pioneered the “ream and run” surgery, where a metal humeral head component is matched with a reamed socket that is resurfaced biologically with fibrocartilage over time. The socket is smoothed, with preservation of the glenoid labrum and removal of any ridges for the socket to enhance stability of the shoulder.5 Many patients in my practice have returned to high-level sporting activities, weight training, and heavy labor jobs after traditional ream and run surgery using a metal humeral head, and now more recently with the pyrocarbon humeral head component.

I have been performing pyrocarbon hemiarthroplasty surgeries regularly since it became widely available in the USA in 2023 (FDA approval was in 2022).8 Shoulder hemiarthroplasty with a pyrocarbon humeral head and glenoid resurfacing arthroplasty is a surgery for active people who want to return to gym activities, sports, or heavy labor without the restrictions typically recommended for TSA or RSA—and also want the potential benefits of the newer pyrocarbon component material properties. The combination of traditional ream and run principles with the pyrocarbon humeral head component is my preferred method for treating young and active people that want to continue high-intensity work or recreational activities. One caveat: there is a risk of pyrocarbon implant fracture9 and implant destruction from contact with metal implants (e.g., suture anchors). Any metal anchor or implant within the socket that could contact the pyrocarbon humeral component must be removed prior to or during surgery to avoid implant failure.

I perform the pyrocarbon hemiarthroplasty with these tools and techniques to enhance the reproducibility and accuracy of the surgery. 

1. I use a short length, press-fit prosthesis autograft from the humeral head for enhanced fixation .

2. The Blueprint 3D preoperative planning program is used to facilitate analysis of the unique shoulder anatomy. Blueprint helps me with decision-making before I get to the operating room. I can help narrow the range of possible implant sizes that would be appropriate and use this sphere of best fit tool to avoid over-stuffing the joint with a prosthesis that is too large.

3. Physical therapy and home exercises are both vital to success after partial shoulder replacement using the pyrocarbon humeral head component. The main emphasis during the early recovery is on passive overhead stretching to avoid a frozen shoulder while protecting the subscapularis repair.

4. The glenoid labrum is preserved to enhance the stability and function of the hemiarthroplasty.

5. Patients can optimize their outcomes by preparing for surgery with a focus on whole-body health to support healing. This includes nutritional optimization, having strong social support at home, and a full understanding of the perioperative care plan. Medical optimization is also critical with cessation of all tobacco and nicotine products being required before surgery.

6. Pyrocarbon shoulder hemiarthroplasty with glenoid resurfacing can be performed in an ambulatory setting—either in a hospital or an ambulatory surgery center—for healthy patients with a reliable support system for recovery at home.

7. Multimodal pain control with a focus on minimizing the use of opioids is key to a comfortable surgery while minimizing the risk of complications. This also involves the use of a regional nerve block for most patients.

Reference/s:

1. NEER CS 2nd. Articular replacement for the humeral head. J Bone Joint Surg Am. 1955 Apr;37-A(2):215-28. PMID: 14367414. 

2. Bohsali, Kamal I. MD; Bois, Aaron J. MD, MSc, FRCSC; Wirth, Michael A. MD. Complications of Shoulder Arthroplasty. The Journal of Bone and Joint Surgery 99(3):p 256-269, February 1, 2017. | DOI: 10.2106/JBJS.16.00935 

3. Long J, Varshenya K, Blevins K, Ralph J, Bryniarski A, Park C, Meyer L, Lau B. Primary Total Shoulder Arthroplasty is Superior to Hemiarthroplasty for the Treatment of Glenohumeral Arthritis: Analysis of 5-year Outcomes in a Large Surgical Database. J Shoulder Elb Arthroplast. 2023 Oct 20;7:24715492231207482. doi: 10.1177/24715492231207482. PMID: 37867634; PMCID: PMC10590041.

4. Clinton J, Franta AK, Lenters TR, Mounce D, Matsen FA 3rd. Nonprosthetic glenoid arthroplasty with humeral hemiarthroplasty and total shoulder arthroplasty yield similar self-assessed outcomes in the management of comparable patients with glenohumeral arthritis. J Shoulder Elbow Surg. 2007 Sep-Oct;16(5):534-8. doi: 10.1016/j.jse.2006.11.003. Epub 2007 May 16. PMID: 17509900.

5. Gilmer BB, Comstock BA, Jette JL, Warme WJ, Jackins SE, Matsen FA. The prognosis for improvement in comfort and function after the ream-and-run arthroplasty for glenohumeral arthritis: an analysis of 176 consecutive cases. J Bone Joint Surg Am. 2012 Jul 18;94(14):e102. doi: 10.2106/JBJS.K.00486. PMID: 22810409.

6. Klawitter JJ, Patton J, More R, Peter N, Podnos E, Ross M. In vitro comparison of wear characteristics of PyroCarbon and metal on bone: Shoulder hemiarthroplasty. Shoulder Elbow. 2020 Dec;12(1 Suppl):11-22. doi: 10.1177/1758573218796837. Epub 2018 Sep 11. PMID: 33343712; PMCID: PMC7726179.

7. McBride AP, Ross M, Hoy G, Duke P, Page R, Peng Y, Taylor F. Mid-term outcomes of pyrolytic carbon humeral resurfacing hemiarthroplasty compared with metal humeral resurfacing and metal stemmed hemiarthroplasty for osteoarthritis in young patients: analysis from the Australian Orthopaedic Association National Joint Replacement Registry. J Shoulder Elbow Surg. 2022 Apr;31(4):755-762. doi: 10.1016/j.jse.2021.08.017. Epub 2021 Sep 20. PMID: 34555523.

8. https://www.accessdata.fda.gov/cdrh_docs/reviews/DEN220012.pdf

9. Pangaud C, Gonzalez JF, Galvin JW, Gauci MO, Boileau P. Fracture of pyrocarbon humeral head resurfacing implant: a case report. J Shoulder Elbow Surg. 2020 Aug;29(8):e306-e312. doi: 10.1016/j.jse.2020.02.028. Epub 2020 Jun 9. Erratum in: J Shoulder Elbow Surg. 2021 Mar;30(3):e136. doi: 10.1016/j.jse.2020.11.001. PMID: 32713470.