Midterm results of anatomic total shoulder arthroplasty with a third-generation implant

Outcomes after reverse shoulder arthroplasty for the treatment of glenohumeral osteoarthritis in patients under and over 70 years of age: a propensity score-matched analysis

INTRODUCTION

As reverse shoulder arthroplasty (RSA) continues to grow in popularity for the treatment of glenohumeral osteoarthritis (GHOA) with an intact rotator cuff, it becomes increasingly important to identify factors that influence postoperative outcome. Although recent studies have demonstrated excellent postoperative range of motion and patient-reported outcome scores following RSA for GHOA, there continues to be surgeon hesitation to adopt RSA as a viable treatment in the younger patient population due to greater functional demands. In this study, we sought to determine the effect of age on clinical outcomes following RSA for GHOA through a comparison of patients over and under the age of 70.

METHODS

A retrospective review of prospectively collected data from an institutional registry was performed. Propensity score matching was utilized to match patients under the age of 70 (U-70) to those over 70 (O-70) in a 1:1 ratio based on sex, body mass index (BMI), preoperative ASES score, preoperative active forward elevation (FE), Walch classification, and American Society of Anesthesiologists comorbidity score. Clinical outcomes obtained preoperatively and at a minimum of 2 years postoperatively consisted of Visual Analog Scale (VAS) for pain, Single Assessment Numeric Evaluation (SANE) score, and American Shoulder and Elbow Surgeons (ASES) score, as well as active (FE), internal rotation, and external rotation. Descriptive statistics and univariate analysis were performed to compare cohorts.

RESULTS

After matching, each cohort consisted of 66 patients with similar mean follow-up periods (U-70, 28.1 ± 7.5 months vs. O-70, 27.4 ± 7.5 months; P = .887). Mean age of the U-70 cohort was 66.2 ± 3.3 while the O-70 cohort had a mean age of 75.3 ± 3.8. Both groups demonstrated significant improvement in VAS, SANE, and ASES scores, as well as active range of motion in all planes. The only significant difference between cohorts was greater postoperative FE in younger patients (143 ± 16° vs. 136 ± 15°; P = .017), though the baseline-to-postoperative improvement in FE was similar between cohorts (50 ± 29° vs. 43 ± 29°, P = .174).

CONCLUSION

RSA is a successful surgical treatment for GHOA regardless of age. Aside from greater postoperative FE in younger patients, there were no other differences in clinical outcomes between younger and older patients in this retrospective analysis, which compared patients who were matched by sex, BMI, and Walch classification, among other factors. Based on our results, 70 years of age should not be used as a threshold in preoperative counseling when determining whether a patient with GHOA with an intact rotator cuff is indicated for reverse shoulder arthroplasty.

Indication matters: effect of indication on clinical outcome following reverse total shoulder arthroplasty-a multicenter study

BACKGROUND

As the utilization and success of reverse total shoulder arthroplasty (RTSA) have continued to grow, so have its surgical indications. Despite the adoption of RTSA for the treatment of glenohumeral osteoarthritis (GHOA) with an intact rotator cuff and irreparable massive rotator cuff tears (MCTs) without arthritis, the literature remains sparse regarding the differential outcomes after RTSA among these varying indications. Thus, the purpose of this study was to examine the postoperative clinical outcomes of RTSA based on indication.

METHODS

A retrospective review of 2 large institutional databases was performed to identify all patients who underwent RTSA between 2015 and 2019 with minimum 2-year follow-up. Patients were stratified by indication into 3 cohorts: GHOA, rotator cuff tear arthropathy (CTA), and MCT. Baseline demographic characteristics were collected to determine differences between the 3 cohorts. Clinical outcomes were measured preoperatively and postoperatively, including active range of motion, American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation score, and visual analog scale pain score. Multivariate linear regression was performed to determine the factors independently predictive of the postoperative ASES score.

RESULTS

A total of 625 patients (383 with GHOA, 164 with CTA, and 78 with MCTs) with a mean follow-up period of 33.4 months were included in the analysis. Patients with GHOA had superior ASES scores (85.6 ± 15.7 vs. 76.6 ± 20.8 in CTA cohort [P < .001] and 75.9 ± 19.9 in MCT cohort [P < .001]), Single Assessment Numeric Evaluation scores (86 ± 20.9 vs. 76.7 ± 24.1 in CTA cohort [P < .001] and 74.2 ± 25.3 in MCT cohort [P < .001]), and visual analog scale pain scores (median [interquartile range], 0.0 [0.0-1.0] vs. 0.0 [0.0-2.0] in CTA cohort [P < .001] and 0.0 [0.0-2.0] in MCT cohort [P < .001]) postoperatively. Postoperative active forward elevation (P < .001) and improvement in active external rotation (P < .001) were greatest in the GHOA cohort compared with other indications. Multivariate linear regression demonstrated that the factors independently associated with the postoperative ASES score included a diagnosis of GHOA (β coefficient, 7.557 [P < .001]), preoperative ASES score (β coefficient, 0.114 [P = .009]), female sex (β coefficient, -4.476 [P = .002]), history of surgery (β coefficient, -3.957 [P = .018]), and postoperative complication (β coefficient, -13.550 [P < .001]).

CONCLUSION

RTSA for the treatment of GHOA generally has superior patient-reported and functional outcomes when compared with CTA and MCTs without arthritis. Long-term follow-up is needed to identify the lasting implications of such outcome differences.

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.

Postoperative complications of reverse total shoulder arthroplasty: a multicenter study in Japan

Background

Reverse total shoulder arthroplasty (RSA) has been approved since 2014 in Japan, and the number of RSA cases has been accumulating. However, only short-to medium-term outcomes have been reported, with a small number of case series, because of its short history in Japan. This study aimed to evaluate complications after RSA in hospitals affiliated with our institute, with comparison to those in other countries.

Methods

A multicenter retrospective study was performed at 6 hospitals. In total, 615 shoulders (mean age: 75.7 ± 6.2 years; mean follow-up: 45.2 ± 19.6 months) with at least 24 months of follow-up were included in this study. The active range of motion was assessed pre-and postoperatively. The 5-year survival rate was evaluated for reoperation for any reason in 137 shoulders with at least 5 years of follow-up using Kaplan-Meier analysis. Postoperative complications were evaluated, including dislocation; prosthesis failure; deep infection; periprosthetic, acromial, scapular spine, and clavicle fractures; neurological disorders; and reoperation. Furthermore, imaging assessments, including scapular notching, prosthesis aseptic loosening, and heterotopic ossification were evaluated on postoperative radiography at the final follow-up.

Results

All range of motion parameters were significantly improved postoperatively (P < .001). The 5-year survival rate was 93.4% (95% confidence interval: 87.8%-96.5%) for reoperation. Complications occurred in 256 shoulders (42.0%), with reoperation in 45 (7.3%), acromial fracture in 24 (3.9%), neurological disorders in 17 (2.8%), deep infection in 16 (2.6%), periprosthetic fracture in 11 (1.8%), dislocation in 9 (1.5%), prosthesis failure in 9 (1.5%), clavicle fracture in 4 (0.7%), and scapular spine fracture in 2 (0.3%). Regarding imaging assessments, scapular notching was observed in 145 shoulders (23.6%), heterotopic ossification in 80 (13.0%), and prosthesis loosening in 13 (2.1%).

Conclusion

This is the first large case series to investigate the complications after RSA in Japan, and the overall frequency of complications after RSA was similar to that in other countries.

Patients With Mild Osteoarthritis Are Less Likely to Achieve a Clinically Important Improvement in Pain or Function After Anatomic Total Shoulder Arthroplasty

BACKGROUND

The severity of glenohumeral osteoarthritis (OA) as demonstrated by preoperative radiographs and patient-reported pain plays an important role in the indication for anatomic total shoulder arthroplasty (aTSA). In hip and knee research, data about the effect of the severity of preoperative radiographic OA on the outcome of total joint arthroplasty have been mixed. For shoulder replacement, we are unsure of the effects of radiographic severity on outcomes.

QUESTIONS/PURPOSES

This study investigated whether the preoperative radiographic severity of glenohumeral OA is associated with improvement in pain and function after aTSA. We asked, (1) does the severity of glenohumeral OA correlate with improvement in patient-reported outcomes after TSA (delta American Shoulder and Elbow Surgeons score [postoperative-preoperative], delta Single Assessment Numeric Evaluation, delta Simple Shoulder Test, and delta VAS)? (2) Is having mild osteoarthritis associated with not meeting the minimum clinically important differences in preoperative and postoperative American Shoulder and Elbow Surgeons scores?

METHODS

An institutional query of patients who underwent aTSA for OA was performed between January 2015 and December 2018. A total of 1035 patients were eligible; however, only patients with adequate preoperative radiographs and patient-reported outcome measures collected preoperatively and at a minimum of 2 years postoperatively were included. Patients with proximal humerus fractures, inflammatory arthropathy, cuff tear arthropathy, prior ipsilateral rotator cuff repair, brachial plexus injury or neuromuscular disorder, workers compensation, periprosthetic joint infection, or revision surgery within 2 years were excluded. Patient characteristics, comorbidities, and prior shoulder surgery were recorded. The severity of OA was classified based on the modified Samilson-Prieto and Walch classification. The association between Samilson-Prieto grade and patient-reported outcome measures (American Shoulder and Elbow Surgeons Score, Single Assessment Numeric Evaluation, Simple Shoulder Test, and VAS score) was evaluated. Radiographic characteristics, patient demographics, comorbidities, and prior surgery were also evaluated for the potential risk of not achieving improvement in the minimum clinically important difference (16.1) with respect to the American Shoulder and Elbow Surgeons score. The American Shoulder and Elbow Surgeons score is scored 0 to 100, with higher scores representing less pain and better function. A total of 206 patients (20% of those eligible) with a mean follow-up of 2.3 years were included. Twenty-three patients had Samilson-Prieto Grade I, 38 had Grade II, 57 had Grade III, and 88 had Grade IV.

RESULTS

There were no differences in improvements (delta) between the groups and between patient-reported outcome scores (American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation, Simple Shoulder Test, and VAS). Compared with patients with more severe osteoarthritis (Samilson-Prieto Grades II, III, and IV), a higher proportion of patients with less severe osteoarthritis (Grade I) did not exceed the minimum clinical important difference for the American Shoulder and Elbow Surgeons score (22% [five of 23] versus 4% [seven of 183]; odds ratio 0.14 [95% confidence interval 0.04 to 0.520]; p = 0.006).

CONCLUSION

The improvement in patient-reported outcome measure scores was similar regardless of radiographic severity after aTSA. Surgeons should use caution when recommending surgery to patients with less severe OA because a higher percentage did not improve, based on the minimum clinically important difference.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The impact of tobacco use on clinical outcomes and long-term survivorship after anatomic total shoulder arthroplasty

Introduction

Postoperative outcomes following total shoulder arthroplasty can be affected by preoperative health factors such as tobacco usage.

Methods

The charts of patients who underwent anatomic total shoulder arthroplasty were retrospectively analyzed and stratified based on smoking status. The primary data included range of motion and patient reported outcomes. Additionally, demographic, radiographic, and survivorship analyses were conducted. All data were analyzed using statistical inference.

Results

There were 78, 49, and 16 non-smoker, former smoker, and current smoker shoulders respectively with no significant differences in sex, American Society of Anesthesiologists status, body mass index, or mean follow-up time (average: 10.7 yrs). Smokers (51.5 ± 10.4 years) were younger than both non-smokers (64.9 ± 8.1 years; p < 0.01) and former smokers (65.1 ± 9.1years; p < 0.01) at the time of surgery. For non-smokers and former smokers, all range of motion and patient reported outcome scores significantly improved. Smokers reported significant improvements in all patient reported outcomes and external and internal rotation. Visual Analog Scale, American Shoulder and Elbow, and Simple Shoulder Test scores were lower for smokers comparatively, but these differences did not reach significance. Forward elevation was higher postoperatively for non-smokers (149.7o ± 17.2o) and former smokers (147.1o ± 26.0o) compared to current smokers (130.9o ± 41.2o; p = 0.017). No differences between the cohorts were found in the radiographic analysis. Revision rates were lower in the non-smoking cohort (7.7%) compared to both former (20.4%; p = 0.036) and current smokers (37.5%; p < 0.01). Survival curves showed that non-smoker implants lasted longer than those of current smokers.

Conclusion

After a decade, patients generally had improved shoulder range of motion, functionality, and pain regardless of smoking status. However, current smokers required shoulder replacements sooner and revision surgery more frequently.

Glenoid Retroversion Does Not Impact Clinical Outcomes or Implant Survivorship Following Total Shoulder Arthroplasty with Minimal, Non-Corrective Reaming

Hypothesis

Methods

Results

Conclusion

Inlay total shoulder arthroplasty for primary glenohumeral arthritis

Background

Anatomic total shoulder arthroplasty with a nonspherical humeral head and inlay glenoid replacement has been introduced in the past; however, clinical evidence remains limited. We hypothesized that patients with advanced glenohumeral arthritis demonstrate significant improvements in pain and function.

Methods

Prospective patient-reported outcomes (PROs) included the American Shoulder and Elbow Surgeons score, a pain visual analog scale, and satisfaction. Range of motion was compared to the preoperative status. A sensitivity analysis examined responder rates and compared them to literature thresholds using the minimal clinically important difference and substantial clinical benefit. The preoperative glenoid morphology was determined using the Walsh classification. Zone-specific periprosthetic radiolucent lines were quantified at the last follow-up.

Results

Thirty-nine shoulders in 36 patients (3 bilateral) with a mean age of 65.9 years (26 males, 13 females) and a mean follow-up of 41.0 months were included. Ninety-three percent had grade III osteoarthritis, and 7% grade II. The glenoid Walsh classification included A1 (25%), A2 (25%), B1 (22%), B2 (25%), and C (3%). All PROs improved significantly (P < .001) with a mean American Shoulder and Elbow Surgeons score from 30.4 to 77.1, a pain visual analog scale from 8.1 to 1.5, and excellent (9.1/10) patient satisfaction. PRO-related responder rates for minimal clinically important difference and substantial clinical benefit were ≥85%. Forward elevation improved from 107° to 155°, and external rotation from 22° to 51°. One intraoperative glenoid rim fracture led to advanced radiolucency; no other clinically relevant lucency was observed.

Conclusion

Treatment with inlay total shoulder arthroplasty demonstrated significant functional improvement, excellent pain relief, and patient satisfaction in patients with advanced shoulder arthritis and various glenoid morphology types. Our initial results provide further support for this new option in primary shoulder replacement.

Subluxation in the Arthritic Shoulder

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The term "subluxation" means partial separation of the joint surfaces. In the arthritic shoulder, "arthritic glenohumeral subluxation" refers to displacement of the humeral head on the surface of the glenoid.

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The degree of arthritic glenohumeral subluxation can be measured using radiography with standardized axillary views or computed tomography (CT).

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Shoulders with a type-B1 or B2 glenoid may show more posterior subluxation on an axillary radiograph that is made with the arm in an elevated position than on a CT scan that is made with the arm at the side.

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The degree of arthritic glenohumeral subluxation is not closely related to glenoid retroversion.

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The position of the humeral head with respect to the plane of the scapula is related to glenoid retroversion and is not a measure of glenohumeral subluxation.

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Studies measuring glenohumeral subluxation before and after arthroplasty should clarify its importance to the clinical outcomes of shoulder reconstruction.

Results of stemless shoulder arthroplasty: a systematic review and meta-analysis

Stemless shoulder arthroplasty relies solely on cementless metaphyseal fixation and is designed to avoid stem-related problem such as intraoperative fractures, loosening, stress shielding or stress-risers for periprosthetic fractures.

Many designs are currently on the market, although only six anatomic and two reverse arthroplasty designs have results published with a minimum of two-year follow-up.

Compared to stemmed designs, clinical outcome is equally good using stemless designs in the short and medium-term follow-up, which is also the case for overall complication and revision rates.

Intraoperative fracture rate is lower in stemless compared to stemmed designs, most likely due to the absence of intramedullary preparation and of the implantation of a stem.

Radiologic abnormalities around the humeral implant are less frequent compared to stemmed implants, possibly related to the closer resemblance to native anatomy.

Between stemless implants, several significant differences were found in terms of clinical outcome, complication and revision rates, although the level of evidence is low with high study heterogeneity; therefore, firm conclusions could not be drawn.

There is a need for well-designed long-term randomized trials with sufficient power in order to assess the superiority of stemless over conventional arthroplasty, and of one design over another.

Cite this article: EFORT Open Rev 2021;6:35-49. DOI: 10.1302/2058-5241.6.200067

Humeral stem lucencies correlate with clinical outcomes in anatomic total shoulder arthroplasty

Background

Humeral stem lucencies are uncommon after uncemented anatomic total shoulder arthroplasty (aTSA), and their clinical significance is unknown. This study compares clinical outcomes of aTSA with and without humeral stem lucencies.

Methods

Two-hundred eighty aTSAs using an uncemented grit-blasted metaphyseal-fit humeral stem between 2005 and 2013 were retrospectively evaluated for radiographic humeral stem lucencies. All shoulders were evaluated at a minimum 5-year follow-up from a multicenter database. Clinical outcomes included range of motion (ROM) and American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score, Constant score, University of California-Los Angeles Shoulder Score (UCLA), Simple Shoulder Test (SST), and Shoulder Pain and Disability Index (SPADI) scores. Postoperative radiographs were evaluated and complications were recorded.

Results

Two-hundred forty-three humeral stems showed no radiolucent lines. Among the 37 humeral stems with lucent lines, lines were most common in zones 8, 4, 7, and 3. Preoperative ROM and functional outcomes were similar between groups. Postoperative change in outcomes exceeded the minimal clinically important difference (MCID) for all ROM and outcomes in both groups. Postoperative change between groups showed no significant difference in ROM or outcome scores, but improved mean abduction exceeded the MCID in the patients without humeral lines. The complication rate after omitting patients with humeral loosening was higher in patients with humeral lucencies, as was the revision rate. There was also a higher glenoid-loosening rate in patients with humeral lucencies.

Conclusion

Humeral lucent lines after uncemented stemmed aTSA have a small negative effect on ROM and functional outcomes compared with patients without lucent humeral lines, which may not be clinically significant. The complication and revision rates were significantly higher in patients with humeral lucencies.

Medial calcar bone resorption after anatomic total shoulder arthroplasty: does it affect outcomes?

BACKGROUND

The incidence of medial calcar resorption has been shown to be common after uncemented total shoulder arthroplasty (TSA). With etiologies including stress shielding, debris-induced osteolysis, and infection, the clinical impact of medial calcar resorption has not been specifically examined. The purpose of this study was to determine whether resorption is associated with inferior outcomes or higher rates of radiographic loosening in TSA patients.

METHODS

We conducted a retrospective review of TSA patients with minimum 2-year clinical follow-up. Patient-reported and functional outcome measures were recorded preoperatively and postoperatively. Postoperative radiographs were evaluated for glenoid and humeral component loosening. A new calcar resorption grading system was introduced to quantify the degree of resorption and assess the progression.

RESULTS

A total of 171 patients met the inclusion criteria, with average clinical and radiographic follow-up periods of 50 and 46 months, respectively. Calcar resorption was identified in 110 patients (64.3%). No significant overall differences were observed between the patients with and without calcar resorption. Subgroup analysis showed that patients with grade 3 resorption had a higher incidence of glenoid radiolucencies (50%, P = .001) and patients with a progression from grade 1 to grade 3 had higher incidences of glenoid (50%, P = .003) and humeral (9%, P = .039) radiolucencies.

CONCLUSION

Medial calcar resorption following TSA with a standard-length press-fit humeral component is common. Overall, no differences in patient-reported outcome measures or radiographic loosening were found compared with patients without calcar resorption. However, grade 3 calcar resorption and more dramatic progression of resorption should raise the suspicion of prosthetic loosening.