Total Shoulder Arthroplasty in Patients with a B2 Glenoid Addressed with Corrective Reaming: Mean 8-year Follow-up

Total shoulder arthroplasty for primary glenohumeral osteoarthritis: does posterior humeral subluxation persist after correction of the glenoid version at 5 years minimum?

BACKGROUND

Primary glenohumeral osteoarthritis is associated with both excessive posterior humeral subluxation (PHS) and excessive glenoid retroversion in 40% of cases. These morphometric abnormalities are a particular issue because they may be responsible for a deterioration in long-term clinical and radiologic outcomes. The aim of this study was to perform a computed tomographic (CT) analysis of patients who underwent total shoulder arthroplasty (TSA) for primary osteoarthritis (OA) with B2-, B3-, or C-type glenoids in whom an attempt was made to correct for excessive glenoid retroversion and excessive posterior humeral subluxation intraoperatively.

MATERIAL

We performed a retrospective, single-center study including 62 TSA patients with a preoperative PHS of the glenohumeral joint (31 men, 31 women, 70 ± 9 years) between January 2000 and January 2014. Glenoids were classified as B2 (32 cases), B3 (13 cases), or C (17 cases). Glenoid retroversion was corrected by anterior asymmetric reaming. Patients were reviewed for clinical and CT scan assessment with a mean follow-up of 8.3 years (minimum 5 years). At final follow-up, the CT images were reconstructed in the scapular plane. A PHS index >65% defined persistence.

RESULTS

The revision-free rate was estimated at 93%. Correlation between PHS and retroversion was moderate preoperatively (ρ = 0.58) and strong at final follow-up (ρ = 0.73). Postoperative CT scans on average showed a surgical correction of PHS compared to preoperatively (79% vs. 65% respectively, P < .05) and retroversion (20° vs. 10° respectively, P < .05). At final follow-up, 25 of 62 patients had a persistence in the 2-dimensional (2D) model and 41 of 62 in the corrected 2D model. Persistence of PHS had no influence on clinical outcomes but did demonstrate a significantly higher glenoid loosening rate (20% vs. 59%, P < .05).

CONCLUSION

Correlation between PHS and retroversion was moderate preoperatively and strengthened at long-term follow-up. Anterior asymmetric reaming allowed for a surgical improvement of both PHS and retroversion, but it was not sufficient to maintain a correction over time. Glenoid loosening was more frequent in case of PHS persistence but seemingly without clinical relevance.

Does glenoid version and its correction affect outcomes in anatomic shoulder arthroplasty? A systematic review

BACKGROUND

Correction of glenoid retroversion is commonly performed in anatomic total shoulder arthroplasty (TSA) to increase component contact area and decrease eccentric loading of the glenoid component. Despite demonstrated biomechanical advantages, limited information exists on the clinical benefit of correcting glenoid retroversion. The purpose of this systematic review is to critically evaluate the existing literature on the effect of preoperative and postoperative glenoid retroversion on clinical functional and radiologic outcomes in patients who underwent anatomic TSA.

METHODS

A systematic literature review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses using PubMed, Embase, and Cochrane Library evaluating the impact of glenoid retroversion on clinical and radiologic outcomes of TSA. English-language studies of level I through IV evidence were included. Blinded reviewers conducted multiple screens and methodological quality was appraised using the Modified Coleman Methodology Score.

RESULTS

Sixteen studies, including 3 level III and 13 level IV studies (1211 shoulders), satisfied all inclusion criteria. To address glenoid retroversion, 9 studies used corrective reaming techniques, and 4 studies used posteriorly augmented glenoids. Two studies used noncorrective reaming techniques. Mean preoperative retroversion ranged from 12.7° to 24° across studies. Eleven studies analyzed the effect of glenoid retroversion on clinical outcomes, including patient-reported outcome scores (PROs), range of motion (ROM), or clinical failure or revision rates. Most studies (8 of 11) did not report any significant association of pre- or postoperative glenoid retroversion on any clinical outcome. Of the 3 studies that reported significant effects, 1 study reported a negative association between preoperative glenoid retroversion and PROs, 1 study reported inferior postoperative abduction in patients with postoperative glenoid retroversion greater than 15°, and 1 study found an increased clinical failure rate in patients with higher postoperative retroversion. Ten studies reported radiographic results (medial calcar resorption, Central Peg Lucency [CPL] grade, Lazarus lucency grade) at follow-up. Only 1 study reported a significant effect of pre- and postoperative retroversion greater than 15° on CPL grade.

CONCLUSION

There is currently insufficient evidence that pre- or postoperative glenoid version influences postoperative outcomes independent of other morphologic factors such as joint line medialization. Given that noncorrective reaming demonstrated favorable postoperative outcomes, and postoperative glenoid version was not significantly and consistently found to impact outcomes, there is inconclusive evidence that correcting glenoid retroversion is routinely required.

Patients 75 years or older with primary glenohumeral arthritis and an intact rotator cuff show similar clinical improvement after reverse or anatomic total shoulder arthroplasty

BACKGROUND

The optimal management of primary glenohumeral arthritis (GHOA) in the elderly is an ongoing topic of debate. The purpose of this study was to compare functional outcomes and complications in patients aged 75 years or older treated with anatomic total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (RSA) for primary GHOA with an intact rotator cuff.

METHODS

A retrospective study was performed on a prospectively maintained database which was queried for patients 75 years of age or older who underwent TSA or RSA for primary GHOA with an intact rotator cuff at a single institution between 2012 and 2021 with minimum 2-year follow-up. Patient-reported outcomes (PROs), including Visual Analog Scale for pain, American Shoulder and Elbow Surgeons, and Subjective Shoulder Value, as well as active range of motion including forward flexion, external rotation, internal rotation, were collected preoperatively and postoperatively. Complications, reoperations, and satisfaction were also recorded. The percentage of patients achieving clinically significant improvement was evaluated with the minimally clinical important difference, substantial clinical benefit, and patient acceptable symptomatic state for each PRO.

RESULTS

One-hundred and 4 patients were available for analysis, including 67 TSA patients and 37 RSAs with a mean follow-up of 39.4 months. Preoperative baseline characteristics, PROs, and range of motion were similar between groups. RSA was more commonly performed for eccentric glenoid wear (Walch B2/B3, 62% vs. 22%; P < .001). While clinical outcomes improved comparably in both groups, the TSA cohort showed significantly greater improvement in external rotation (36° vs. 26°; P = .013). Both cohorts had low revision (3% for TSA vs. 0% for RSA) and complication (7% for TSA vs. 5% for RSA; P = .677) rates. Satisfaction was similar in both groups (93% for TSA vs. 92% for RSA; P = .900). Clinically significant improvement was comparable between groups based on the American Shoulder and Elbow Surgeons score (minimally clinical important difference, 93% for TSA vs. 100% for RSA; substantial clinical benefit, 82% vs. 95%; patient acceptable symptomatic state, 67% vs. 78%; P > .05).

CONCLUSION

In this retrospective small sample size comparison study, TSA and RSA provide similar short-term clinical outcomes for patients 75 years and older with primary GHOA and an intact rotator cuff. Complication and revision rates are comparably low at short-term follow-up. Our data suggests that advanced age alone should not be used as a decision-making tool for TSA vs. RSA in the setting of primary GHOA with an intact rotator cuff.

Three-dimensional analysis of biplanar glenoid deformities: what are they and can they be virtually reconstructed with anatomic total shoulder arthroplasty implants?

BACKGROUND

Descriptions of glenoid deformities in glenohumeral osteoarthritis (GHOA) have focused on the axial plane. Less is known regarding arthritic glenoids with higher amounts of superior inclination and little evidence exists to guide management of inclination or combined version-inclination deformity when performing anatomic total shoulder arthroplasty (aTSA). We hypothesized that biplanar deformities (BD) would be present in a higher proportion of GHOA patients than previously appreciated, and these deformities would be difficult to adequately reconstruct with contemporary aTSA implants.

METHODS

A retrospective query was performed of GHOA patients indicated for TSA 2012-2017 with a computed tomography (CT) scan within three months of surgery. Images were uploaded to three-dimensional (3D) software for automated measurements. Glenoids with superior inclination ≥10°, and retroversion ≥20° were considered to have BD. Walch classification was determined, and C-type glenoids were excluded. Rotator-cuff muscle cross-sectional area (CSA) was measured and fatty infiltration was graded. Glenoids with BD were virtually planned for aTSA with correction to neutral inclination and version, then with 5° superior inclination and 10° retroversion.

RESULTS

Two-hundred and sixty-eight shoulders in 250 patients were included; average age was 65 years, 67% male. There were no differences in inclination between Walch types (P = .25). Twenty-nine shoulders with BD were identified (11%). These deformities were not associated with age (P = .47) or gender (P = .50) but were skewed towards Walch B-type, specifically B2 (P = .03). Acromial index and posterior humeral head subluxation were higher in BD patients (P = .04, P < .001, respectively). Biplanar deformities had similar cuff CSA compared to those without but were less frequently associated with fatty infiltration of the subscapularis (P = .05). When correcting to neutral version and inclination, 41% BD could not be reconstructed. Of those that could, 94% required augmented implants. When correcting to 5° superior inclination and 10° retroversion, 10% could not be reconstructed. Of those that could, 58% required augmented implants. With partial correction, augment use was predicted by retroversion >26° (P = .009). Inclination did not predict augment use (P = .90). Final implant position commonly involved unseating in the posterosuperior quadrant and cancellous exposure in the anteroinferior quadrant.

CONCLUSIONS

This retrospective computed tomography (CT)-based study of 268 shoulders with GHOA found an 11% prevalence of BD. These deformities were commonly associated with Walch B2 wear patterns. Virtual aTSA planning showed a high failure rate (41%) when correcting to neutral version and inclination. Posteriorly augmented implants were frequently required, and often still involved unseating in the posterosuperior quadrant, increased cancellous exposure in the anteroinferior quadrant, and vault perforation.