Shoulder replacement

Radiographic images of frontal views of shoulders before and after total shoulder arthroplasty. (A) The preoperative anatomy and (B) the placement of the humeral component can be clearly seen. The UHMWPE glenoid component in (B) is radiolucent and is evident only as a space between the humeral component and bone of the glenoid (images courtesy of Jon jP Warner, Massachusetts General Hospital). 

The number of shoulder arthroplasty procedures done yearly has grown from an estimated 5000 per year in the United States between 1990 and 1992 (Wirth and Rockwood, Jr. 1996) to around 15,000 per year between 2002 and 2003 (Jackson 2003). Of these, a substantial portion are hemiarthroplasties. The prevalence of hemiarthroplasties as a percentage of the total number of replacements ranges from 14% (Edwards et al. 2002) in a multicenter study of OA, to 65% in a study of fracture repair (Boileau et al. 2001), to 87% in the Swedish shoulder arthroplasty register started in 1999 (Rahme, Jacobsen, and Salomonsson 2(X)1). Dr. Charles Neer, II, the pioneer of tiie procedure, estimates that overall, aroimd 20% of shoulder replacements are hemiarthroplasties (2003). 

Fracture/trauma is the next most common problem addressed by shoulder replacement. Snyder reports the rate as 9% (1996), Torchia and associates as 12% (1997), Neer and colleagues as 23% (1982), Sojbjerg and colleagues as 30% (1999), and Rahme and associates as 35% (2001). In fact, repair of the humerus after fracture was the driving reason for the development of the first modem shoulder replacement component (Neer, II 2003) and the first reported series of modern shoulder replacements were done to correct problems caused by humeral fractures (Neer, II1974). 

All other indications leading to total shoulder replacement (TSR) are generally below approximately 5% each over a range of reported studies (Snyder 1996). It is interesting to note, however, that replacement required for revision of prior surgery has been reported to be from 0% to about 4% (Snyder 1996) to 6% (Rahme, Jacobsen, and Salomonsson 2001) up to 11% (Neer, II, Watson, and Stanton 1982) of all cases. 

The first recorded TSR was performed by a French surgeon named Fean in 1893 using a constrained design (connected glenoid and humeral components) to treat tuberculous arthritis of the shoulder (Lugli 1978). The patient was a 37-year-old man and the prosthesis components reportedly functioned relatively well until they were removed 2 years later because of infection (Lugli 1978). 

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Shoulder replacement, although done much less frequently than hip and knee replacement, is the third most prevalent joint replacement procedure worldwide. Current shoulder replacement systems rely on ultra-high molecular weight polyetiiylene (UHMWPE) components for motion and load bearing. Because of this critical role, the performance of UHMWPE components can determine the overall performance of the replacement system. 

Chapter 9 The Clinical Performance of UHMWPE in Shoulder Replacements... 

The modern era of shoulder replacement was ushered in by Dr. Charles Neer, II. In 1953, in response to the relatively poor results of humeral head resection for patients with proximal humeral fractures. Dr. Neer implanted a vital-hum humeral component of his own design in a hemiarthroplasty procedure (Figure 9.4). In 1955, he reported on his first series of 12 pahents treated in this way. 

The foimdation that Neer laid for shoulder replacement can be seen today in many ways. The continued production and use of the 1973 version of his humeral component as the Neer II and the many other humeral and glenoid components based on this original design is testament to its stature in the surgical community. The basic concepts included in the Neer prosthesis such as all-polyethylene and metal-backed keeled glenoid components and wire... 

Canada Newswire. 2003. "First North American reverse shoulder replacement surgery performed at Toronto Western Hospital." March 25, 2003. 

De Wilde L., M. Mombert, R. Van Retegem, and R. Verdonk. 2001. Revision of shoulder replacement with a reversed shoulder prosthesis (Delta III) Report of five cases. Acta Orthop Belg 67 348-353. 

Neer C.S., 11, K.C. Watson, and EJ. Stanton. 1982. Recent experience in total shoulder replacement. J Bone Joint Surg 64 319-337. 

Sojbjerg J.O., L.H. Frich, H.V. Johaimsen, and O. Sneppen. 1999. Late results of total shoulder replacement in patients with rheumatoid arthritis. Clin Orthop 366 39-45. 

Wirth M.A., and Rockwood C.A., Jr. 1996. Complications of total shoulder-replacement arthroplasty. J Bone Joint Surg 78 603-616. 

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