Stepped Augmented Glenoid Component in Anatomic Total Shoulder Arthroplasty for B2 and B3 Glenoid Pathology: A Study of Early Outcomes.

Posterior glenoid bone loss is commonly associated with primary glenohumeral osteoarthritis. Surgical management of bone loss in anatomic total shoulder arthroplasty (aTSA) remains controversial. We studied the use of a stepped augmented glenoid component for management of Walch B2 and B3 glenoids and compared the radiographic and clinical outcomes at short-term follow-up with those achieved with a non-augmented component of the same design in Walch A1 glenoids. Ninety-two patients (42 A1, 29 B2, and 21 B3 glenoids) were prospectively followed after aTSA. Sequential 3-dimensional (3D) computed tomography (CT) imaging was performed preoperatively, within 3 months postoperatively with metal artifact reduction (MAR) to define implant position, and at a minimum of 2 years postoperatively with MAR. Scapular 3D registration with implant registration allowed 3D measurement of glenoid implant position, implant shift, and central peg osteolysis (CPO). CPO with or without implant shift occurred in a higher percentage of B3 glenoids treated with the augmented glenoid component (29%) than A1 glenoids treated with a standard component (5%) (p = 0.028). There was no significant difference in the frequency of CPO between B2 glenoids with the augmented component (10%) and A1 glenoids with the standard component. There was no difference in postoperative glenoid component version and inclination between groups. B3 glenoids were associated with more component medialization relative to the premorbid joint line compared with A1 and B2 glenoids (p < 0.001). A stepped augmented glenoid component can restore premorbid glenoid anatomy in patients with asymmetric biconcave glenoid bone loss (Walch B2), with short-term clinical and radiographic results equivalent to those for patients without glenoid bone loss (Walch A1) treated with a non-augmented component. There is a greater risk of CPO in patients with moderate-to-severe B3 glenoid pathology with this stepped augmented glenoid component. Longer follow-up will help define the clinical implications of CPO over time. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Iannotti JP ，Jun BJ ，Derwin KA ，Ricchetti ET ... -  《-》

Relationship Between Glenoid Component Shift and Osteolysis After Anatomic Total Shoulder Arthroplasty: Three-Dimensional Computed Tomography Analysis.

The purpose of this study was to evaluate glenoid component position and radiolucency following anatomic total shoulder arthroplasty (TSA) using sequential 3-dimensional computed tomography (3D CT) analysis. In a series of 152 patients (42 Walch A1, 16 A2, 7 B1, 49 B2, 29 B3, 3 C1, 3 C2, and 3 D glenoids) undergoing anatomic TSA with a polyethylene glenoid component, sequential 3D CT analysis was performed preoperatively (CT1), early postoperatively (CT2), and at a minimum 2-year follow-up (CT3). Glenoid component shift was defined as a change in component version or inclination of ≥3° from CT2 to CT3. Glenoid component central anchor peg osteolysis (CPO) was assessed at CT3. Factors associated with glenoid component shift and CPO were evaluated. Glenoid component shift occurred from CT2 to CT3 in 78 (51%) of the 152 patients. CPO was seen at CT3 in 19 (13%) of the 152 patients, including 15 (19%) of the 78 with component shift. Walch B2 glenoids with a standard component and glenoids with higher preoperative retroversion were associated with a higher rate of shift, but not of CPO. B3 glenoids with an augmented component and glenoids with greater preoperative joint-line medialization were associated with CPO, but not with shift. More glenoid component joint-line medialization from CT2 to CT3 was associated with higher rates of shift and CPO. A greater absolute change in glenoid component inclination from CT2 to CT3 and a combined absolute glenoid component version and inclination change from CT2 to CT3 were associated with CPO. Neither glenoid component shift nor CPO was associated with worse clinical outcomes. Postoperative 3D CT analysis demonstrated that glenoid component shift commonly occurs following anatomic TSA, with increased inclination the most common direction. Most (81%) of the patients with glenoid component shift did not develop CPO. Longer follow-up is needed to determine the relationships of glenoid component shift and CPO with loosening over time. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Ricchetti ET ，Jun BJ ，Jin Y ，Ho JC ，Patterson TE ，Dalton JE ，Derwin KA ，Iannotti JP ... -  《-》

Three-dimensional computed tomography analysis of pathologic correction in total shoulder arthroplasty based on severity of preoperative pathology.

The purpose of this study was to quantify correction of glenoid deformity and humeral head alignment in anatomic total shoulder arthroplasty as a function of preoperative pathology (modified Walch classification) and glenoid implant type in a clinical cohort using 3-dimensional computed tomography (CT) analysis. Patients undergoing anatomic total shoulder arthroplasty with a standard glenoid (SG) (n = 110) or posteriorly stepped augmented glenoid (AG) (n = 62) component were evaluated with a preoperative CT scan and a postoperative CT scan within 3 months of surgery. Glenoid version, inclination, and medial-lateral (ML) joint line position, as well as humeral head alignment, were assessed on both CT scans, with preoperative-to-postoperative changes analyzed relative to pathology and premorbid anatomy based on the modified Walch classification and glenoid implant type. On average, correction to the premorbid ML joint line position was significantly less in type A2 glenoids than in type A1 glenoids (-2.3 ± 2.1 mm vs. 1.1 ± 0.9 mm, P < .001). Correction to premorbid version was not different between type B2 glenoids with AG components and type A1 glenoids with SG components (-1.7° ± 6.6° vs. -1.0° ± 4.0°, P = .57), and the premorbid ML joint line position was restored on average in both groups (0.3 ± 1.6 mm vs. 1.1 ± 0.9 mm, P = .006). Correction to premorbid version was not different between type B3 glenoids with AG components and type A1 glenoids with SG components (-0.6° ± 5.1° vs. -1.0° ± 4.0°, P = .72), but correction relative to the premorbid ML joint line position was significantly less in type B3 glenoids with AG components than in type A1 glenoids with SG components (-2.2 ± 2.1 mm vs. 1.1 ± 0.9 mm, P < .001). Postoperative humeral glenoid alignment was not different in any group comparisons. In cases with posterior glenoid bone loss and retroversion (type B2 or B3 glenoids), an AG component can better correct retroversion and the glenoid ML joint line position compared with an SG component, with correction to premorbid version comparable to a type A1 glenoid with an SG component. However, restoration of the premorbid ML joint line position may not always be possible with SG or AG components in cases with more advanced central glenoid bone loss (type A2 or B3 glenoids). Further follow-up is needed to determine the clinical consequences of these findings.

Ricchetti ET ，Jun BJ ，Jin Y ，Entezari V ，Patterson TE ，Derwin KA ，Iannotti JP ... -  《-》

Clinical and Radiographic Outcomes of a Posteriorly Augmented Glenoid Component in Anatomic Total Shoulder Arthroplasty for Primary Osteoarthritis with Posterior Glenoid Bone Loss.

Ho JC ，Amini MH ，Entezari V ，Jun BJ ，Alolabi B ，Ricchetti ET ，Iannotti JP ... -  《-》

Outcomes of anatomic shoulder arthroplasty performed on B2 vs. A1 type glenoids.

Glenoid component malpositioning and glenoid component retroversion have been associated with higher rates of radiolucencies, raising concerns about its implications on glenoid loosening and ultimate failure of anatomic total shoulder arthroplasty (TSA). Although there is literature regarding the relative advantages of techniques to address posterior glenoid bone loss, we are not aware of studies comparing outcomes of TSA on these challenging Walch type B2 glenoids vs. more common A1 glenoids. The purpose of this study is to compare outcomes of TSA performed on A1 glenoids and B2 glenoids treated with asymmetric glenoid reaming. We identified 1045 shoulders that had primary TSAs performed for osteoarthritis in a prospective shoulder arthroplasty registry. Two hundred eighty-nine shoulders met inclusion criteria of a preoperative Walch type A1 (178) or B2 (111) glenoid morphology, treatment with TSA, asymmetric reaming in the B2 group, and a minimum of 2-year clinical and radiographic follow-up. Postoperative radiographs were assessed for lucencies, and patient-reported outcome measures were collected at all follow-up visits. Follow-up averaged 40 ± 15 months for all patients, and more men presented with a B2 glenoid (80 of 111; 72%) compared with A1 (101 of 178; 57%) (P = .009). Age at surgery (P = .166), dominant-sided surgery (P = .281), body mass index (P = .501), smoking (P = .155), preoperative opioid use (P = .154), and diabetes (P = .331) were not significantly different between groups. Both groups had similar Constant Strength scores preoperatively (A1: 4.7 ± 7.1, and B2: 4.3 ± 7.3) but the B2 group improved significantly more at final follow-up (A1: 10.3 ± 6.2 vs. B2: 12.7 ± 6.7, P = .005). The Total Constant score was also significantly better at follow-up in the B2 glenoid group (P = .039). All other Constant subscales, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), and Single Assessment Numerical Evaluation (SANE) measures showed significant improvement preoperatively to final follow-up (all P <.001) but there were no significant differences between the A1 and B2 glenoid groups (all P > .05). A similar proportion of patients rated their satisfaction as either very satisfied or satisfied between the A1 (160; 90%) and B2 (100; 90%) (P = .613). Lazarus scores were also similar between the A1 and B2 groups (P = .952) as were the rates of humeral radiolucent lines (P = .749) and humeral osteolysis (P = .507). Although patients with B2 glenoids may present a more technically challenging anatomic total shoulder arthroplasty, treatment with concurrent asymmetric glenoid reaming produced similar, successful clinical and radiographic early to midterm outcomes for patients undergoing TSA compared with A1 glenoids. Additional follow-up on this cohort will be important to confirm the durability of these early results.

Sheth MM ，Morris BJ ，Laughlin MS ，Cox JL ，Jones S ，Elkousy HA ，Edwards TB ... -  《-》