Results after primary reverse shoulder arthroplasty with and without subscapularis repair: a prospective-randomized trial

Intraoperative repair of functional subscapularis during RSA by deltopectoral approach could improve internal rotation but does not prevent anterior dislocation

INTRODUCTION

The role of the subscapularis following reverse shoulder arthroplasty (RSA) remains controversial as repair could restore adequate internal rotation and shoulder stability, but might compromise external rotation. The purpose of this multi-centre study, on a large cohort of RSAs performed using the deltopectoral approach, was to determine the effect of subscapularis preoperative status and intraoperative repair on range of motion, clinical scores and rates of complications at a minimum follow-up of 2 years.

HYPOTHESIS

Repair of a functional subscapularis grants better internal rotation and stability without compromising external rotation.

MATERIALS AND METHODS

We retrospectively reviewed records of all RSAs (n=916) performed by 14 surgeons that participated in a large national society symposium, and excluded 234 operated by the anterosuperior approach, 42 operated for rheumatoid arthritis, fractures, instability or post traumatic sequalae, and eight that had adjuvant latissimus dorsi tendon transfer (LDTT). This left 632 RSAs, in which the subscapularis was detached in 594, and repaired after detachment in 495. Patients completed pre- and postoperative Constant Score and postoperative Subjective Shoulder Value (SSV). Active forward elevation, active external rotation (ER), and active internal rotation (IR) were recorded pre- and postoperatively. Complications following RSA that required conservative treatment, reoperation without implant removal, as well as reoperation with implant removal were recorded.

RESULTS

Of the initial cohort of 632 shoulders, 120 (19%) were lost to follow-up, 12 (2%) died due to causes unrelated to RSA, and 26 (4%) were revised with implant removal. Of the remaining 474 shoulders, 259 (55%) had a functional repaired subscapularis (Group FR), 59 (12%) had a non-functional repaired subscapularis (Group nFR), whereas 68 (14%) had a not repaired subscapularis (Group nR). Comparison of patient demographics revealed no significant differences among the three groups. Postoperative Constant Score (p=0.031) and SSV (p=0.016) were significantly different among the three groups, but effect sizes were small and not clinically relevant. Differences in postoperative ER as well as postoperative IR were not significant among the three groups: 91 (35%) gained functional IR in Group FR, 11 (19%) in Group nFR, and 13 (19%) in Group nR. Three shoulders (1.2%) reported subjective instability and 1 (0.4%) dislocated in Group FR, but none in either Groups nFR or nR.

DISCUSSION

Despite statistically significant differences in Constant Score and SSV among the three groups, the clinical relevance of these differences is negligible, so repair of functional subscapularis has little or no influence on functional outcomes. During RSA by deltopectoral approach, repair of a functional subscapularis could slightly improve internal rotation in some patients but does not compromise external rotation, forward elevation or clinical scores, while repair of a non-functional subscapularis, compared to non-repair, did not improve range of motion or clinical scores.

LEVEL OF EVIDENCE

III; retrospective comparative.

Clinical outcomes of over-the-top subscapularis repair in reverse shoulder arthroplasty

Background

Biomechanical research demonstrates increased subscapularis abduction range of motion (ROM) when the tendon's upper two-thirds is repaired over-the-top of the center of rotation during reverse shoulder arthroplasty (RSA). This study compares the clinical outcomes of patients undergoing RSA with over-the-top subscapularis repair (OTTR) to patients without repair.

Methods

We retrospectively reviewed 97 consecutive RSAs with either OTTR of the subscapularis (N = 75) or no repair (N = 22). Repair was attempted in all patients but not performed if the subscapularis could not be brought to the over-the-top position in 20° of external rotation (ER) and 30° of abduction. Improvements in ROM were compared to the minimal clinically important difference for RSA.

Results

The mean follow-up was 3.8 ± 1.6 years. Demographics were similar between groups. Preoperatively, patients undergoing repair had greater ER when compared to those without repair (15 ± 16° vs. 5 ± 12°, P = .003). Postoperatively, patients undergoing repair had greater forward elevation (132 ± 21° vs. 126 ± 22°, P = .268) and abduction (114 ± 26° vs. 106 ± 23°, P = .193) with both exceeding the minimal clinically important difference (-2.9° and -1.9°, respectively); however, not statistically significant. Patients with repair were more frequently able to reach the small of their back postoperatively (65% vs. 21%, P = .006) but had less improvement in ER (13 ± 20° vs. 24 ± 20°, P = .028). Postoperative outcome scores, complications, and reoperations were similar between groups.

Discussion

OTTR of the subscapularis in RSA had similar ROM and outcome scores compared to no repair, but a significantly larger proportion of patients with repair achieved functional internal rotation to the small of the back. ER limitations seen after conventional repair may also apply to this novel technique, but without a corresponding detrimental effect on forward elevation or abduction.

Radiologic, clinical, and patient-reported outcomes in stemless reverse shoulder arthroplasty at a mean of 46 months

BACKGROUND

The humeral stem can be a cause of problems in shoulder arthroplasty, for example, loss of bone stock, intraoperative and postoperative periprosthetic fractures, or postoperative infections involving the medullary canal. Therefore, stemless reverse shoulder arthroplasty (slRSA) has gained popularity, particularly in terms of preserving bone stock. However, there are limited data available on the midterm outcomes of slRSA. The objective of this study was to evaluate the clinical, radiologic, and patient-reported outcomes of slRSA at a minimum follow-up period of 2 years.

METHODS

Data on all stemless reverse shoulder prostheses implanted between January 2016 and October 2020 were collected. Patients were followed up at 6 weeks and 6, 12, and 24 months postoperatively. Clinical and radiologic data as well as patient-reported outcome measures were assessed with validated questionnaires (University of California at Los Angeles Shoulder Score [UCLA], American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES], Quick Disabilities of the Arm, Shoulder, and Hand questionnaire [Quick-DASH], visual analog scale [VAS] for pain, Subjective Shoulder Value [SSV], and Constant-Murley score [CS]). All patients had a minimum follow-up of 2 years.

RESULTS

During the observation period, 26 shoulders in 25 patients fulfilled the inclusion criteria. The mean follow-up was 46.8 months (range 25-66). The mean age was 70.1 years (range 59.9-86.4). At the most recent follow-up, a significant improvement was noted in the ASES score (55.9 ± 19.9 vs. 85.6 ± 10.7, P < .001), SSV (44.3 ± 18.7 vs. 85.3 ± 10.4, P < .001), Quick-DASH score (40.6 ± 22.0 vs. 17.8 ± 13.9, P < .001), VAS pain score (4.6 ± 3.2 vs. 0.9 ± 1.2, P < .001), and range of motion in flexion (66 ± 53 vs. 154 ± 22, P < .001) as well as in the absolute (44.1 ± 18.7 vs. 83.1 ± 10.1, P < .001) and relative CS (62.1 ± 27.8 vs. 111.9 ± 13.3, P < .001). Scapular notching was observed in 16% of cases, and radiolucent lines were detected in 28% of cases without symptoms of implant loosening. No revision was necessitated by any causes related to the stemless humeral component. Hence, implant survivorship was 100%.

CONCLUSIONS

With an ASES score showing a 30-point improvement and thus exceeding the minimal clinically important difference of 21 points and no revisions due to the stemless component, these results indicate that slRSA is a viable option, providing good to excellent midterm outcomes that are comparable to those of stemmed reverse shoulder prostheses, with the added advantage of bone stock preservation.

Reverse shoulder arthroplasty for primary glenohumeral osteoarthritis: significantly different characteristics and outcomes in shoulders with intact vs. torn rotator cuff

PURPOSE

To compare outcomes of reverse shoulder arthroplasty (RSA) for primary osteoarthritis (OA) with and without rotator cuff (RC) tears to those with secondary OA due to RC tears.

METHODS

We reviewed records of all patients who received RSA for primary OA or secondary OA. All patients had preoperative radiographs, computed tomographic arthrography (CTA), and/or magnetic resonance imaging (MRI) scans of their shoulders to assess their etiology, glenoid morphology, and fatty infiltration. Pre- and postoperative (at minimum follow-up of 2 years) Constant scores and range of motion were compared between patients who had RSA for primary OA with and without RC tears to those with secondary OA due to RC tears.

RESULTS

Of the initial cohort of 605 shoulders (583 patients), 153 were lost to follow-up (25.3%), 25 required revision with implant removal (4.1%), and 13 died of causes unrelated to the surgery (2.1%), and left a final cohort of 414 patients. Of the final cohort, 97 had primary OA with intact RC, 62 had primary OA with RC tears, and 255 had secondary OA. Postoperative Constant scores were significantly higher for primary OA with intact RC (73.8 ± 14.3), compared with both primary OA with RC tears (66.1 ± 14.6, P < .001) and secondary OA (64.1 ± 14.8, P < .001). There were no differences in pre- or postoperative scores between primary OA with RC tears and secondary OA.

CONCLUSION

At 2 or more years following RSA, Constant scores were significantly higher for primary OA with intact RC, compared to either primary OA with RC tears or secondary OA, whereas there were no differences in pre- or postoperative scores of shoulders that had primary OA with RC tears vs. secondary OA. The authors recommend distinguishing primary OA with intact RC from primary OA with RC tears, as the two have considerably different characteristics and prognosis following RSA.

Analysis of three different reverse shoulder arthroplasty designs for cuff tear arthropathy - the combination of lateralization and distalization provides best mobility

BACKGROUND

The two major reverse shoulder arthroplasty (RSA) designs are the Grammont design and the lateralized design. Even if the lateralized design is biomechanically favored, the classic Grammont prosthesis continues to be used. Functional and subjective patient scores as well as implant survival described in the literature so far are comparable to the lateralized design. A pure comparison of how the RSA design influences outcome in patients has not yet been determined. The aim of this study was a comparison focused on patients with cuff tear arthropathy (CTA).

METHODS

We analyzed registry data from 696 CTA patients prospectively collected between 2012 and 2020 in two specialized orthopedic centers up to 2 years post-RSA with the same follow-up time points (6,12 24 months). Complete teres minor tears were excluded. Three groups were defined: group 1 (inlay, 155° humeral inclination, 36 + 2 mm eccentric glenosphere (n = 50)), group 2 (inlay, 135° humeral inclination, 36 + 4 mm lateralized glenosphere (n = 141)) and group 3 (onlay, 145° humeral inclination, + 3 mm lateralized base plate, 36 + 2 mm eccentric glenosphere (n = 35)) We compared group differences in clinical outcomes (e.g., active and passive range of motion (ROM), abduction strength, Constant-Murley score (CS)), radiographic evaluations of prosthetic position, scapular anatomy and complications using mixed models adjusted for age and sex.

RESULTS

The final analysis included 226 patients. The overall adjusted p-value of the CS for all time-points showed no significant difference (p = 0.466). Flexion of group 3 (mean, 155° (SD 13)) was higher than flexion of group 1 (mean, 142° (SD 18) and 2 (mean, 132° (SD 18) (p < 0.001). Values for abduction of group 3 (mean, 145° (SD 23)) were bigger than those of group 1 (mean, 130° (SD 22)) and group 2 (mean, 118° (SD 25)) (p < 0.001). Mean external rotation for group 3 (mean, 41° (SD 23)) and group 2 (mean, 38° (SD 17)) was larger than external rotation of group 1 (mean, 24° (SD 16)) (p < 0.001); a greater proportion of group 2 (78%) and 3 (69%) patients reached L3 level on internal rotation compared to group 1 (44%) (p = 0.003). Prosthesis position measurements were similar, but group 3 had significantly less scapular notching (14%) versus 24% (group 2) and 50% (group 1) (p = 0.001).

CONCLUSIONS

Outcome scores of different RSA designs for CTA revealed comparable results. However, CTA patients with a lateralized and distalized RSA configuration were associated with achieving better flexion and abduction with less scapular notching. A better rotation was associated with either of the lateralized RSA designs in comparison with the classic Grammont prosthesis.

LEVEL OF EVIDENCE

Therapeutic study, Level III.

Reverse shoulder arthroplasty with a 155° neck-shaft angle inlay implant design without reattachment of the subscapularis tendon results in satisfactory functional internal rotation and no instability: a cohort study

BACKGROUND

The aim of this study was to use the Activities of Daily Living which require Internal Rotation (ADLIR) questionnaire to assess the functional internal rotation in patients who had undergone reverse shoulder arthroplasty (RSA) without reattachment of the subscapularis (SSc) tendon at a minimum follow-up of 2 years. The secondary aim was to report the objective range of motion (ROM) and the rate of postoperative instability.

MATERIALS AND METHODS

All consecutive primary RSA procedures without reattachment of the SSc tendon that were performed using a Delta Xtend prosthesis (an inlay system with a 155° neck-shaft angle) between January 2015 and December 2020 were identified to ensure a minimum follow-up of 2 years. Patients were contacted and requested to fill in several questionnaires, including the ADLIR and Auto-Constant scores.

RESULTS

In total, 210 patients met the inclusion criteria; among those patients, 187 could be contacted and 151 completed questionnaires (response rate: 81%). The SSc tendon was fully detached without repair in all cases, and a superolateral approach was used in 130 (86%) cases. The median follow-up was 4.5 years (range: 2.0-7.6). At final follow-up, the mean ADLIR score was 88/100 (interquartile range (IQR): 81-96). The median level reached in internal rotation was the 3rd lumbar vertebra (IQR: lumbosacral region-12th thoracic vertebra). Of the 210 eligible patients, one required a revision for a dislocation within the first month after primary surgery. With regards to regression analysis with ADLIR score as the outcome, none of the factors were associated with the ADLIR score, although age and smoking approached significance (0.0677 and 0.0594, respectively). None of the explanatory variables were associated with ROM in internal rotation (p > 0.05).

CONCLUSIONS

This study demonstrates that satisfactory ADLIR scores and internal rotation ROM were obtained at mid-term follow-up after RSA leaving the SSc detached. Leaving the SSc detached also did not lead to high instability rates; only one out of 210 prostheses was revised for dislocation within the first month after primary surgery.

LEVEL OF EVIDENCE III

The effect of subscapularis repair in reverse total shoulder arthroplasty depends on the design of the implant: a comparative study with a minimum 2-year follow-up

INTRODUCTION

The role of the subscapularis (Ssc) tendon does not yet have a well-defined role in RSA. The purpose of the present study was to evaluate if the repair of the Ssc in RSA improves overall clinical and radiographic results and if it has the same results using a medialized design humeral stem compared to a lateralized design.

METHODS

Eighty-four consecutive patients undergoing RSA were retrospectively analyzed. Nine patients were lost at FU. Two implants with similar glenosphere design and different stem design (medialized and lateralized) were used. The Ssc was repaired in case of good quality of the fibers and reducibility without tension intraoperatively. Patients were divided into four groups for data analysis depending on whether they had received a medialized or lateralized design and Ssc repair or not. Patients were reviewed at an average follow-up of 40.8 ± 13.1 months. Clinical outcome measures included Active range of motion (ROM), strength, visual analog scale (VAS), Constant-Murley score (CMS), and the American Shoulder and Elbow Surgeons score (ASES). Radiographic evaluation at final follow-up was performed to assess scapular notching, stress shielding, and radiolucent lines.

RESULTS

No statistically significant clinical differences (p > 0.05) emerged between Lat/Ssc+ and Lat/Ssc-. Conversely, the patients belonging to the Med/Ssc- group reported statistically worse (p < 0.05) results than the Med/Ssc + group in terms of VAS, ASES and CMS. Statistically worse (p < .05) results in the Med/Ssc- group than in the Med/Ssc + were found also in active ROM achieved in FE, ABD, ER1 and ER2, and in the strength obtained in FE, ABD and ER2. Scapular notching was reported in 3 shoulders (15.7%) in Lat/Ssc+ group and in 7 shoulders (50%) in Lat/Ssc- group, while it was reported in 4 shoulders (14.2%) in Med/Ssc + group and in 6 shoulders (42.8%) in Med/Ssc- group. Stress shielding was observed in 6 cases in Lat/Ssc+ group (31.6%), in 8 cases in Lat/Ssc- group (57.1%), in 3 cases (10.7%) in Med/Ssc + group and 4 cases in Med/Ssc- group (28.6%).

CONCLUSIONS

Patients undergoing RSA show clinical improvements at mid-term follow-up with a low rate of complications, regardless of the use of a medialized or a lateralized humeral stem design. Ssc repair is associated with better functional outcomes in the cohort of medialized stem, while it did not yield significant differences in the cohort of lateralized stem.

LEVEL OF EVIDENCE

Level III; Retrospective Cohort Comparison; Treatment Study.

Subscapularis repair for reverse shoulder arthroplasty: a systematic review and meta-analysis

BACKGROUND

The purpose of this study is to perform a systematic review of the literature evaluating the importance of subscapularis repair in patients who underwent reverse shoulder arthroplasty (RSA).

METHODS

A systematic search of articles in PubMed, EMBASE, and the Cochrane Library databases was carried out according to the PRISMA guidelines. Cohort studies comparing RSA with subscapularis repair vs. RSA without subscapularis repair were included. All statistical analysis was performed using Review Manager. A P value of <.05 was considered to be statistically significant.

RESULTS

Seventeen studies with 2620 patients were included. Subscapularis repair resulted in less instability compared to without subscapularis repair (0.8% vs. 4.2%, P = .04), and there were no significant differences in rate of instability with lateralization (0.6% vs. 1.6%, P = .40), revision rates (2.6% vs. 3.9%, P = .62), and complication rates (7.7% vs. 4.9%, P = .21). Subscapularis repair had improved American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) scores (83.6 vs. 80.2, P = .02) and Constant scores (72.6 vs. 68.9, P < .01) but there was not a significant difference in visual analog scale pain scores (1.2 vs. 1.6, P = .11). Subscapularis repair had a significant difference in forward flexion (140° vs. 137°, P = .04) and internal rotation score (5.5 vs. 4.6, P = .001); however, there was no significant difference in external rotation (35° vs. 35°, P = .80) and abduction (117° vs. 123°, P = .13).

CONCLUSION

This study found that RSA with subscapularis repair demonstrated a reduction in the occurrence of implant instability with medialized implants. However, subscapularis repair did not yield improvements in revision rates, complications, or instability with lateralized implants. Additionally, other outcome measures such as ASES, Constant score, and range of motion exhibited statistically significant improvements with subscapularis repair but did not surpass clinically significant thresholds.

Outcomes of Reverse Total Shoulder Arthroplasty for Proximal Humerus Fracture Versus Rotator Cuff Arthropathy

INTRODUCTION

Reverse total shoulder arthroplasty (RSA) is used to treat a variety of shoulder-related pathologies. This study compared medium-term clinical outcomes of less than 10-year follow-up in patients treated with RSA for proximal humerus fracture (PHF) versus rotator cuff arthropathy (RCA).

METHODS

This retrospective review was conducted at two tertiary care centers, in which self-reported clinical outcomes were assessed using four validated instruments, that is, American Shoulder and Elbow Society (ASES) score, Shoulder Pain and Disability Index (SPADI), visual analog scale (VAS), and shoulder subjective value (SSV). Statistical analyses were performed using linear or logistic regression with generalized estimating equations.

RESULTS

Of the 189 patients included in this study, 70 were treated for fracture and 119 for RCA. At a mean postoperative follow-up of 6.4 years, the means were 79.7 for ASES score, 20.8 for SPADI-Total, 0.8 for VAS, and 77.1 for SSV. After adjusting models for covariates, there was no significant difference in average SSV (P = 0.7), VAS (P = 0.7) or SPADI-Pain (P = 0.2) between PHF and RCA cohorts; however, the RCA cohort reported significantly better outcomes in ASES scores (P = 0.002), SPADI-Disability (P < 0.0001), and SPADI-Total (P = 0.0001).

DISCUSSION

Patients with RCA and PHF treated with RSA achieved similar medium-term outcomes in several domains, particularly postoperative pain levels; however, patients with PHF reported greater perceived disability. RSA is an effective pain-controlling procedure, but patients may have variable functional outcomes based on the indication for surgery.

Discordance between patient-reported and objectively measured internal rotation after reverse shoulder arthroplasty

BACKGROUND

Patient satisfaction after reverse shoulder arthroplasty (RSA) partly relies on restoring functional internal rotation (IR). Although postoperative assessment of IR includes objective appraisal by the surgeon and subjective report from the patient, these evaluations may not vary together uniformly. We assessed the relationship between objective, surgeon-reported assessments of IR and subjective, patient-reported ability to perform IR-related activities of daily living (IRADLs).

METHODS

Our institutional shoulder arthroplasty database was queried for patients undergoing primary RSA with a medialized-glenoid lateralized-humerus design between 2007-2019 and minimum 2-year follow-up. Patients who were wheelchair bound or had a preoperative diagnosis of infection, fracture, and tumor were excluded. Objective IR was measured to the highest vertebral level reached with the thumb. Subjective IR was reported based on patients' rating (normal, slightly difficult, very difficult, or unable) of their ability to perform 4 IRADLs (tuck in shirt with hand behind back, wash back or fasten bra, personal hygiene, and remove object from back pocket). Objective IR was assessed preoperatively and at latest follow-up and reported as median and interquartile ranges.

RESULTS

A total of 443 patients were included (52% female) at a mean follow-up of 4.4 ± 2.3 years. Objective IR improved pre- to postoperatively from L4-L5 (buttocks to L1-L3) to L1-L3 (L4-L5 to T8-T12) (P < .001). Preoperatively reported IRADLs of "very difficult" or "unable" significantly decreased postoperatively for all IRADLs (P ≤ .004) except those unable to perform personal hygiene (3.2% vs. 1.8%, P > .99). The proportions of patients who improved, maintained, and lost objective and subjective IR was similar between IRADLs; 14%-20% improved objective IR but lost or maintained subjective IR and 19%-21% lost or maintained the same objective IR but improved subjective IR depending on the specific IRADL assessed. When ability to perform IRADLs improved postoperatively, objective IR also increased (P < .001). In contrast, when subjective IRADLs worsened postoperatively, objective IR did not significantly worsen for 2 of 4 IRADLs assessed. When examining patients who reported no change in ability to perform IRADLs pre- vs. postoperatively, statistically significant increases in objective IR were found for 3 of 4 IRADLs assessed.

CONCLUSIONS

Objective improvement in IR parallels improvements in subjective functional gains uniformly. However, in patients with worse or equivalent IR, the ability to perform IRADLs postoperatively does not uniformly correlate with objective IR. When attempting to elucidate how surgeons can ensure patients will have sufficient IR after RSA, future investigations may need to use patient-reported ability to perform IRADLs as the primary outcome measure rather than objective measures of IR.

The statistical fragility of the management options for reverse shoulder arthroplasty: a systematic review of randomized control trial with fragility analysis

Reverse shoulder arthroplasty (RSA) is used in the treatment of traumatic and arthritic pathologies, with expanding clinical indications and as a result there has been an increase in clinical research on the topic. The purpose of this study was to examine the statistical fragility of randomized control trials (RCTs) reporting outcomes from RSA. A systematic search was undertaken to find RCTs investigating RSA. The Fragility Index (FI) was calculated using Fisher's exact test, by sequentially altering the number of events until there was a reversal of significance. The Fragility Quotient (FQ) was calculated by dividing the FI by the trial population. Each trial was assigned an overall FI and FQ calculated as the median result of its reported findings. Overall, 19 RCTs warranted inclusion in the review, representing 1146 patients, of which 41.2% were male, with a mean age of 74.2 ± 4.3 years and mean follow-up of 22.1 ± 9.9 months. The median RCT population was 59, with a median of 9 patients lost to follow-up. The median FI was 4.5, and median FQ was 0.083, indicating more patients did not complete the trial than the number of outcomes which would have to change to reverse the finding of significance. This review found that the RCT evidence for RSA management may be vulnerable to statistical fragility, with a handful of events required to reverse a finding of significance.

Patient Reported Outcomes and Range of Motion After Reverse Total Shoulder Arthroplasty With and Without Subscapularis Repair

Background

In performing reverse total shoulder arthroplasty (rTSA), the role of repairing the subscapularis has been debated. Our objective was to determine the effect of subscapularis repair following rTSA on postoperative shoulder ranges of motion and patient reported outcome scores (PROs).

Methods

A prospective registry was reviewed to establish a cohort of primary rTSA patients with a 135-degree humeral implant, with a minimum of 2 years of follow-up. Variables collected included demographics, subscapularis repair information, diagnosis, glenosphere size, and glenoid lateralization information. Outcomes collected were range of motion measurements, subscapularis strength, and multiple generic and shoulder PROs. Multivariable linear regression models were created to predict these 2-year outcomes.

Results

The 143-patient cohort had a mean age of 69 years with 68% of patients undergoing subscapularis repair. After adjustment in the multivariable models, whether the subscapularis was repaired did not significantly predict a 2-year forward elevation, external rotation, internal rotation, subscapularis strength, Western Ontario Osteoarthritis of the Shoulder score, VR-12 scores, Constant Score, or American Shoulder and Elbow Surgeons Shoulder Scores. Increased glenoid lateralization significantly predicted greater internal rotation, higher VR-12 physical score, and higher Constant Score. There were no dislocations in either group.

Conclusions

After adjusting for patient and implant factors, subscapularis repair was not associated with a 2-year postoperative range of motion, strength, or any PROs suggesting that repairing the subscapularis may not affect functional outcome. Increased glenoid lateralization through the baseplate and glenosphere independently predicted better internal rotation, VR-12 physical score, and Constant Scores indicating a benefit to lateralization during rTSA.

When should reverse total shoulder arthroplasty be considered in glenohumeral joint arthritis?

Anatomical total shoulder arthroplasty (TSA) has been used widely in treatment of glenohumeral osteoarthritis and provides excellent pain relief and functional results. Reverse total shoulder arthroplasty (RSA) was created to treat the complex problem of rotator cuff tear arthropathy. RSA also has been performed for glenohumeral osteoarthritis even in cases where the rotator cuff is preserved and has shown good results comparable with TSA. The indications for RSA are expanding to include tumors of the proximal humerus, revision of hemiarthroplasty to RSA, and revision of failed TSA to RSA. The purposes of this article were to describe comprehensively the conditions under which RSA should be considered in glenohumeral osteoarthritis, to explain its theoretical background, and to review the literature.