This is a 70‐year‐old active individual with end‐stage osteoarthritis and a Walch type A1 glenoid. Walch type A glenoids are centered, with or without central deformity. Walch type B glenoids are posteriorly eroded with or without deformity, and Walch type C glenoids are considered dysplastic.1 The later varieties are more likely to undergo progressive deformity, subluxation, and pose biomechanical challenges that are potentially time sensitive.^2,3 Since this glenoid is concentrically worn, there is less concern for progression and continued injection treatment can be considered (Figure 60.1 and 60.2).

If conservative treatment fails, hemiarthroplasty or anatomic TSA are common reconstructive options. Both of these options require an intact rotator cuff for ideal function, to avoid anterosuperior escape and early glenoid failure from eccentric loading.⁴ Fortunately, full thickness rotator cuff tears are only present in 7.6% of patients presenting with primary osteoarthritis, and partial thickness tears have not been shown to influence outcome.⁵ This patient has a centered head without radiographic signs of cuff tear arthropathy,⁶ but advanced three‐dimensional imaging may be obtained when there is clinical concern. A full thickness irreparable supraspinatus tear, or any infraspinatus or subscapularis tear, would be a contraindication to primary TSA.

Hemiarthroplasty offers the benefits of preserving glenoid bone stock, less operative time, and less blood loss, and eliminates the risk of glenoid implant failure when compared with TSA. However, hemiarthroplasty carries the inherent risk of progressive glenoid arthritis and pain. While the results have been variable, some authors report success, especially in young active laborers with intractable pain, especially those with a high degree of posterior wear and subluxation where glenoid components would have a higher risk of failure.^7–9 In TSA, resurfacing of the glenoid theoretically decreases long‐term pain and restores physiological tension on the rotator cuff, with the traded risk of glenoid implant failure necessitating later revision surgery.

A randomized controlled trial (RCT) of 42 arthritic shoulders comparing hemiarthroplasty to TSA showed a trend toward improved disease specific quality of life for TSA as measured by the previously validated Western Ontario Osteoarthritis of the Shoulder (WOOS) score,¹⁰ (WOOS 90.6 for TSA vs 81.5 for hemiarthroplasty; p = 0.18) but was underpowered to show a difference.¹¹ Radnay et al. published a systematic review of 23 studies (1952 patients) with an average level of evidence of 3.72 with a mean 43.4 months’ follow‐up.¹² TSA provided significantly greater pain relief (86 vs 78; p <0.0001), forward elevation (p <0.0001), external rotation (p = 0.0002), patient satisfaction (97% vs 80%; p <0.0001), and lower revision rate (10.7% hemiarthroplasty vs 1.7% for TSA with all polyethylene cemented glenoids; p <0.025). Of the included hemiarthroplasties, 10.2% required revisions, 79.4% of which (8.1% of all hemiarthroplasties) were converted to TSA for pain.¹² Economically, TSA is more cost‐effective. Mather et al. created a Markov decision model using available literature to compare cost utility and reported that a TSA is $1970 cheaper per patient than hemiarthroplasty and provides more quality‐adjusted life years (QALYs).¹³ Hemiarthroplasty would not be preferred unless the TSA annual revision rate reached 8.52% or $50 000 in initial cost.¹³ In 2011, the American Academy of Orthopaedic Surgeons (AAOS) concluded there was moderate evidence to recommend TSA over hemiarthroplasty in the surgical management of glenohumeral osteoarthritis.