Study Shows Improved Outcomes with an Inlay Glenoid Shoulder Arthroplasty System
Younger, active adults who underwent anatomic total shoulder arthroplasty (TSA) with an inlay glenoid component and stemless ovoid humeral head experienced improved clinical outcomes and a high rate of return to occupational and sporting activity, with no reoperations or radiographic loosening, according to a study published online by the Journal of Shoulder and Elbow Surgery
“Treatment of young, active patients with glenohumeral osteoarthritis is the subject of considerable debate,” said senior study author Gregory P. Nicholson, MD, from Rush University Medical Center in Chicago, Illinois. “While the demand for TSA in patients younger than 55 is projected to grow at a rate of 8.2% per year, clinical data for an anatomic TSA with inlay glenoid components has been lacking.
“This study shows the numerous benefits of using [an inlay glenoid component and a stemless ovoid humeral head] as a primary solution for achieving pain relief and excellent functional improvements for patients eager to return to normal activity levels and regain quality of life.”
Figure 1. Glenohumeral osteoarthritis treated with an inlay glenoid component and stemless ovoid humeral head (OVO with Inlay Glenoid Shoulder Arthroplasty System, Arthrosurface; Franklin, Massachusetts).
For the study, researchers at Rush University Medical Center retrospectively reviewed data on 24 patients (27 shoulders) with primary or post-traumatic glenohumeral osteoarthritis (OA) who underwent TSA with an inlay glenoid component and stemless ovoid humeral head (OVO with Inlay Glenoid Shoulder Arthroplasty System, Arthrosurface; Franklin, Massachusetts). Minimum follow-up was 2 years, and average age of the patients was 52.1 years. Researchers evaluated:
- Patient-reported outcome measures
- Range of motion
- Return to occupational and sporting activity
Based on the Walch classification of glenohumeral OA,  glenoids in this cohort were graded as:
- A1/A2: 15 shoulders (55%)
- B1: 8 shoulders (30%)
- B2: 4 shoulders (15%)
The researchers found that:
- Patients showed significant progress with outcome measures, active forward flexion, and external rotation (P<0.001) at an average follow-up of 40.4 months.
- Patients reported a high rate of return to work: 92.6% at an average of 3.7 months. More than three quarters of them said they returned to their preoperative occupational demand level after surgery.
- Patients reported a high rate of return to sporting activity: 75% at an average of 9.1 months. Half of them said they achieved the same or a higher level of sporting activity after surgery.
- Radiographs done annually showed no signs of loosening of the inlay component.
This study confirms and replicates a previous study demonstrating excellent patient outcomes and increased range of motion despite the complexity of the anatomy. 
Cvetanovich GL, Naylor AJ, O’Brien MC, Waterman BR, Garcia GH, Nicholson GP. Anatomic total shoulder arthroplasty with an inlay glenoid component: clinical outcomes and return to activity. J Shoulder Elbow Surg. 2019 Dec 31. pii: S1058-2746(19)30707-4. doi: 10.1016/j.jse.2019.10.003. [Epub ahead of print]
- Walch G, Badet R, Boulahia A, Khoury A. Morphologic study of the glenoid in primary glenohumeral osteoarthritis. J Arthroplasty. 1999;14:756–760. doi: 10.1016/S0883-5403(99)90232-2.
- Egger AC, Peterson J, Jones MH, Miniaci A. Total shoulder arthroplasty with nonspherical humeral head and inlay glenoid replacement: clinical results comparing concentric and nonconcentric glenoid stages in primary shoulder arthritis. JSES Open Access. 2019 Sep 13;3(3):145-153. doi: 10.1016/j.jses.2019.07.009. eCollection 2019 Oct.