Anatomic total shoulder arthroplasty for posteriorly eccentric and concentric osteoarthritis: a comparison at minimum 5-year follow-up.

BACKGROUND: In patients with glenohumeral osteoarthritis and posteriorly eccentric wear patterns, the early to mid-term results of TSA using conservative glenoid reaming with no attempt at version correction have been favorable at early follow-up. The purpose of this study is to compare the clinical and radiographic outcomes of TSA using this technique for patients with and without eccentric wear patterns at a minimum 5-year follow-up. METHODS: Patients who underwent TSA with minimum 5-year follow-up were identified from an institutional registry. Preoperative and postoperative radiographs were used to determine humeroglenoid alignment (HGA-AP), humeroscapular alignment (HSA-AP), version, Walch classification and glenoid component seating. The outcome measures were the Simple Shoulder Test, glenoid component radiolucencies, and the occurrence of complications or revisions. RESULTS: Two hundred and ten patients were included in the study, of which 98 (47%) had posteriorly decentered humeral heads and 108 (51%) had centered humeral heads. There were 77 shoulders with Walch type A glenoids and 122 with Walch type B glenoids. At a mean 8-year follow-up, the final SST, change in SST and percentage of maximal improvement was not correlated with pre- and postoperative humeral head centering, Walch classification or glenoid version. There were no preoperative predictors of a low final SST. Two patients (1%) underwent open re-operations during the study period. In patients with Walch B1 and B2 glenoids (n=110), there were no differences in outcome measures between patients with postoperative retroversion of more and less than 15o. While 15 of 51 patients (29%) with minimum 5-year radiographs had glenoid radioluciences, these radiographic findings were not associated with inferior clinical outcomes. On multivariable analysis glenoid component radiolucencies were most strongly associated with incomplete component seating (OR 3.3, p = 0.082). CONCLUSION: The results of TSA with conservative glenoid reaming without attempt at version correction are favorable at minimum 5 year, mean 8-year follow-up. There were no differences in clinical and radiographic outcomes between patients with eccentric and concentric wear patterns. Incomplete glenoid component seating was the greatest predictor of glenoid component radiolucency, but these radiolucencies were not associated with inferior clinical outcomes.

Anatomic shoulder arthroplasty: the correlation between patient resilience, mental health, and outcome.

BACKGROUND: Recovery from anatomic shoulder arthroplasty may be enhanced in patients with good mental health and the resilience to participate in the prescribed postoperative rehabilitation program. To test this concept, we utilized validated and reliable scales in determining whether resilience and mental health are associated with the outcome of anatomic arthroplasty. METHODS: Three hundred ninety-nine patients (195 ream and run [RnR] and 204 anatomic total shoulder arthroplasty [aTSA]) were surveyed at a mean follow-up of 6.3 ± 3.3 years. Preoperative variables included age, sex, body mass index, history of prior shoulder surgery, diabetes, visual analog scale for pain, Simple Shoulder Test (SST) scores, and Veteran's RAND 12 Mental Component Score (VR-12 MCS). Outcomes collected included the SST, American Shoulder and Elbow Surgeons (ASES) score, revision rate, and patient satisfaction. Resilience was documented using the Connor-Davidson Resilience Scale 10 (CD-RISC 10) at latest follow-up. Univariable and multivariable regression analyses were used to identify factors significantly associated with follow-up postoperative SST, ASES, and satisfaction. RESULTS: In the univariable analysis, CD-RISC 10 was positively correlated with postoperative SST, ASES, and satisfaction after both RnR and aTSA. The mean CD-RISC 10 scores were higher in the RnR cohort (34.3 ± 4.8 vs. 32.5 ± 6.2 for aTSA, P < .001). Male sex and lower preoperative visual analog scale for pain were correlated with higher ASES after RnR; VR-12 MCS was positively correlated with all outcomes except SST after RnR. In the multivariable linear regression analysis, CD-RISC 10 was independently associated with postoperative SST, ASES and satisfaction scores in aTSA patients. In the RnR cohort, CD-RISC 10 was only correlated with satisfaction. VR-12 MCS was correlated with ASES and satisfaction after RnR. DISCUSSION: In this study of anatomic arthroplasties, increased resilience and better mental health were correlated with better outcomes. RnR patients had higher resilience than aTSA patients. Greater resilience was associated with better outcomes after aTSA. Better mental health was associated with superior outcomes after the ream and run procedure.

Does adding hydrogen peroxide to chlorhexidine gluconate increase the effectiveness of skin preparation in reducing cutaneous Cutibacterium levels? A randomized controlled trial.

BACKGROUND: Shoulder periprosthetic joint infection is most commonly caused by Cutibacterium. Effective removal of these bacteria from the skin is difficult because Cutibacterium live protected in the dermal sebaceous glands beneath the skin surface to which surgical preparation solutions, such as chlorhexidine gluconate (CHG), are applied. There is conflicting evidence on the additional benefit of using hydrogen peroxide (H2O2) as an adjunct to CHG in eliminating Cutibacterium from the skin. A previous study demonstrated that after CHG skin preparation, repopulation of Cutibacterium from sebaceous glands onto the skin surface occurs in 90% of shoulders by 60 minutes after application. The objective of this randomized controlled study was to determine the effectiveness of adding H2O2 to CHG in reducing skin Cutibacterium. METHODS: Eighteen male volunteers (36 shoulders) were recruited for this study. The 2 shoulders of each volunteer were randomized to receive the control preparation ("CHG-only" - 2% CHG in 70% isopropyl alcohol alone) or the study preparation ("H2O2+CHG" - 3% H2O2 followed by 2% CHG in 70% isopropyl alcohol). Skin swabs were taken from each shoulder prior to skin preparation and again at 60 minutes after preparation. Swabs were cultured for Cutibacterium and observed for 14 days. Cutibacterium skin load was reported using a semiquantitative system based on the number of quadrants growing on the culture plate. RESULTS: Prior to skin preparation, 100% of the CHG-only shoulders and 100% of the H2O2+CHG shoulders had positive skin surface cultures for Cutibacterium. Repopulation of Cutibacterium on the skin at 60 minutes occurred in 78% of CHG-only and 78% of H2O2+CHG shoulders (P = 1.00). Reduction of Cutibacterium skin levels occurred in 56% of CHG-only and 61% of H2O2+CHG shoulders (P = .735). Cutibacterium levels were significantly decreased from before skin preparation to 60 minutes after preparation in both the CHG-only (2.1 ± 0.8 to 1.3 ± 0.9, P = .003) and the H2O2+CHG groups (2.2 ± 0.7 to 1.4 ± 0.9, P < .001). Substantial skin surface levels of Cutibacterium were present at 60 minutes after both preparations. CONCLUSIONS: In this randomized controlled study, there was no additional benefit of using hydrogen peroxide as an adjunct to chlorhexidine gluconate skin preparation in the reduction of cutaneous Cutibacterium levels. Neither preparation was able to eliminate repopulation of Cutibacterium on the skin surface from the dermal sebaceous glands.

2023 Neer Award for Basic Science: Genetics of Cutibacterium acnes in revision shoulder arthroplasty: a large-scale bacterial whole-genome sequencing study.

BACKGROUND: Cutibacterium acnes is the bacterium most commonly responsible for shoulder periprosthetic joint infection (PJI) and is often cultured from samples obtained at the time of revision for failed shoulder arthroplasty. We sought to determine whether these bacteria originate from the patient or from exogenous sources. We also sought to identify which C. acnes genetic traits were associated with the development of shoulder PJI. METHODS: We performed bacterial whole-genome sequencing of C. acnes from a single-institution repository of cultures obtained before or during primary and revision shoulder arthroplasty and correlated the molecular epidemiology and genetic content of strains with clinical features of infection. RESULTS: A total of 341 isolates collected over a 4-year period from 88 patients were sequenced. C. acnes cultured from surgical specimens demonstrated significant similarity to the strains colonizing the skin of the same patient (P < .001). Infrequently, there was evidence of strains shared across unrelated patients, suggesting that exogenous sources of C. acnes culture-positivity were uncommon. Phylotypes IB and II were modestly associated with clinical features of PJI, but all phylotypes appeared inherently capable of causing disease. Chronic shoulder PJI was associated with the absence of common C. acnes genes involved in bacterial quorum-sensing (luxS, tqsA). CONCLUSION: C. acnes strains cultured from deep intraoperative sources during revision shoulder arthroplasty demonstrate strong genetic similarity to the strains colonizing a patient's skin. Some phylotypes of C. acnes commonly colonizing human skin are modestly more virulent than others, but all phylotypes have a capacity for PJI. C. acnes cultured from cases of PJI commonly demonstrated genetic hallmarks associated with adaptation from acute to chronic phases of infection. This is the strongest evidence to date supporting the role of the patient's own, cutaneous C. acnes strains in the pathogenesis of shoulder arthroplasty infection. Our findings support the importance of further research focused on perioperative decolonization and management of endogenous bacteria that are likely to be introduced into the arthroplasty wound at the time of skin incision.

Anatomic Total Shoulder: Predictors of Excellent Outcomes at Five Years after Arthroplasty.

PURPOSE: The objectives of this study were to: report minimum 5-year outcomes in patients undergoing TSA and determine characteristics predictive of patients achieving an excellent functional outcome. METHODS: Pre-operative demographic variables and Simple Shoulder Test (SST) scores were obtained pre-operatively and at a minimum of five years after surgery. A final SST ≥ 10 and percentage of maximal possible improvement (% MPI) of ≥ 66.7% were determined to be the thresholds for excellent outcomes. Univariate and multivariate analysis were performed to identify factors associated with excellent five year clinical outcomes. RESULTS: Of 233 eligible patients, 188 (81%) had adequate follow-up for inclusion in this study. Mean SST scores improved from 3.4 ± 2.4 to 9.7 ± 2.2 (p < 0.001). Male sex was an independent predictor of both SST ≥ 10 (OR 3.46, 95% CI 1.70-7.31; p < 0.001) and %MPI ≥ 66.7 (OR 2.27, 95% CI 1.11-4.81, p = 0.027). Workers' Compensation insurance was predictive of not obtaining SST ≥ 10 (OR 0.12, 95% 0.02-0.60; p = 0.016) or %MPI ≥ 66.7 (OR 0.16, 95% CI 0.03-0.77, p = 0.025). MCID was passed by the vast majority (95%) of patients undergoing TSA and did not necessarily indicate an excellent, satisfactory outcome. CONCLUSION: Male sex and commercial insurance coverage were significantly associated with these excellent outcomes, while Workers' Compensation insurance was associated with failure to achieve this result. Thresholds for excellent outcomes, such as final SST ≥ 10 and %MPI ≥ 66.7, may be useful in identifying the characteristics of patients who benefit most from TSA.