Reverse versus anatomical shoulder arthroplasty in patients with intact rotator cuff

Stratification of the minimal clinically important difference, substantial clinical benefit, and patient acceptable symptomatic state after total shoulder arthroplasty by implant type, preoperative diagnosis, and sex

BACKGROUND

Clinical significance, as opposed to statistical significance, has increasingly been utilized to evaluate outcomes after total shoulder arthroplasty (TSA). The purpose of this study was to identify thresholds of the minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptomatic state (PASS) for TSA outcome metrics and determine if these thresholds are influenced by prosthesis type (anatomic or reverse TSA), sex, or preoperative diagnosis.

METHODS

A prospectively collected international multicenter database inclusive of 38 surgeons was queried for patients receiving a primary aTSA or rTSA between 2003 and 2021. Prospectively, outcome metrics including ASES, shoulder function score (SFS), SST, UCLA, Constant, VAS Pain, shoulder arthroplasty smart (SAS) score, forward flexion, abduction, external rotation, and internal rotation was recorded preoperatively and at each follow-up. A patient satisfaction question was administered at each follow-up. Anchor-based MCID, SCB, and PASS were calculated as defined previously overall and according to implant type, preoperative diagnosis, and sex. The percentage of patients achieving thresholds was also quantified.

RESULTS

A total of 5851 total shoulder arthroplasties (TSAs) including aTSA (n = 2236) and rTSA (n = 3615) were included in the study cohort. The following were identified as MCID thresholds for the overall (aTSA + rTSA irrespective of diagnosis or sex) cohort: VAS Pain (-1.5), SFS (1.2), SST (2.1), Constant (7.2), ASES (13.9), UCLA (8.2), SPADI (-21.5), and SAS (7.3), Abduction (13°), Forward elevation (16°), External rotation (4°), Internal rotation score (0.2). SCB thresholds for the overall cohort were: VAS Pain (-3.3), SFS (2.9), SST 3.8), Constant (18.9), ASES (33.1), UCLA (12.3), SPADI (-44.7), and SAS (18.2), Abduction (30°), Forward elevation (31°), External rotation (12°), Internal rotation score (0.9). PASS thresholds for the overall cohort were: VAS Pain (0.8), SFS (7.3), SST (9.2), Constant (64.2), ASES (79.5), UCLA (29.5), SPADI (24.7), and SAS (72.5), Abduction (104°), Forward elevation (130°), External rotation (30°), Internal rotation score (3.2). MCID, SCB, and PASS thresholds varied depending on preoperative diagnosis and sex.

CONCLUSION

MCID, SCB, and PASS thresholds vary depending on implant type, preoperative diagnosis, and sex. A comprehensive understanding of these differences as well as identification of clinically relevant thresholds for legacy and novel metrics is essential to assist surgeons in evaluating their patient's outcomes, interpreting the literature, and counseling their patients preoperatively regarding expectations for improvement. Given that PASS thresholds are fragile and vary greatly depending on cohort variability, caution should be exercised in conflating them across different studies.

Reverse total shoulder arthroplasty for primary osteoarthritis with restricted preoperative forward elevation demonstrates similar outcomes but faster range of motion recovery compared to anatomic total shoulder arthroplasty

BACKGROUND

Reverse total shoulder arthroplasty (RSA) has been increasingly utilized for a variety of shoulder pathologies that are difficult to treat with anatomical total shoulder arthroplasty (TSA). Few studies have compared the outcomes of TSA vs. RSA in patients with cuff intact glenohumeral osteoarthritis and poor preoperative forward elevation. This study aimed to determine whether there is a difference in functional outcomes and postoperative range of motion (ROM) between TSA and RSA in these patients.

METHODS

This retrospective cohort study included 116 patients who underwent RSA or TSA between 2013 and 2022 for the treatment of rotator cuff intact primary osteoarthritis with restricted preoperative forward flexion (FF) and a minimum 1-year follow-up. Each arthroplasty group was divided into 2 subgroups: patients with preoperative FF between 91° and 120° or FF lower than or equal to 90°. Patients' clinical outcomes, including active ROM, American Shoulder and Elbow Surgeons score, visual analog scale for pain, and subjective shoulder value were collected. Clinical and radiographic complications were evaluated.

RESULTS

There was no significant difference between RSA and TSA in terms of sex (58.3% male vs. 62.2% male, P = .692), or follow-up duration (20.1 months vs. 17.7 months, P = .230). However, the RSA cohort was significantly older (72.0 ± 8.2 vs. 65.4 ± 10.6, P = .012) and weaker in FF and (ER) before surgery (P < .001). There was no difference between RSA (57 patients) and TSA (59 patients) in visual analog scale pain score (1.2 ± 2.3 vs. 1.3 ± 2.3, P = .925), subjective shoulder value score (90 ± 15 vs. 90 ± 15, P = .859), or American Shoulder and Elbow Surgeons score (78.4 ± 20.5 vs. 82.1 ± 23.2, P = .476). Postoperative active ROM was statistically similar between RSA and TSA cohorts in FF (145 ± 26 vs. 146 ± 23, P = .728) and ER (39 ± 15 vs. 41 ± 15, P = .584). However, internal rotation was lower in the RSA cohort (P < .001). This was also true in each subgroup. RSA led to faster postoperative FF and ER achievement at 3 months (P < .001). There was no statistically significant difference in complication rates between cohorts.

CONCLUSION

This study demonstrates that patients with glenohumeral osteoarthritis who have a structurally intact rotator cuff but limited preoperative forward elevation can achieve predictable clinical improvement in pain, ROM, and function after either TSA or RSA. Reverse arthroplasty may be a reliable treatment option in patients at risk for developing rotator cuff failure.

Electromyographic analysis of selected shoulder muscles during shoulder rehabilitation exercises in patients after reverse total shoulder arthroplasty

BACKGROUND

Reverse shoulder arthroplasty (RSA) aims to restore function in patients with rotator cuff failure and joint arthropathy. After surgery, patients are routinely referred to a rehabilitation specialist to regain range of motion, strength, and function. A key element in these programs is active exercises. The exercises are often selected based on assumed muscle activity, investigated by electromyography (EMG). In particular, in this patient population, activation of the deltoid and the scapular muscles is the focus of exercise therapy. Currently, most studies investigating muscle activity levels during exercises are performed on healthy individuals. To our knowledge, no study exists analyzing EMG activity during exercises in a population of shoulder arthroplasty patients. Therefore, the study aimed to analyze activity in the shoulder girdle muscles during 6 commonly used rehabilitation exercises 12 weeks after reverse shoulder arthroplasty surgery.

METHODS

Forty-four patients (50 shoulders) participated in this cross-sectional study, 12 weeks postoperatively (mean 99.18 ± 12.8 days), aged 68.9 ± 7.75 years. Surface EMG activity was measured in 10 shoulder girdle muscles: the 3 trapezius parts, serratus anterior, the 3 deltoid parts, latissimus dorsi, and 2 pectoralis major parts during 6 exercises, 3 in a closed chain, and 3 open chain elevation exercises.

RESULTS

Gravity-minimized exercises (horizontal plane) show low activity for almost all muscles. Vertical closed kinetic chain exercises show an increased activity compared to horizontal plane exercises. Open kinetic chain exercises against gravity showed the greatest activity in deltoid and upper trapezius. For the other muscles, no consistency in progression was found.

CONCLUSION

This study offers a progression of exercises for patients after reverse shoulder arthroplasty based on increased muscle activity.

Defining patient satisfaction after reverse total shoulder arthroplasty: a systematic review

BACKGROUND

The prevalence of reverse total shoulder arthroplasty (rTSA) has grown rapidly. As indications for the procedure expand, the proportion of patients who have satisfactory outcomes after rTSA has not been well defined. This systematic literature review explores overall patient satisfaction after rTSA and defines patient satisfaction based on indication for surgery.

METHODS

A literature search was performed for studies describing patient satisfaction after rTSA in accordance with Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines. Papers were included if they investigated patient satisfaction after rTSA at a minimum of 2-year follow-up. Data were collected on patient demographics, including age, gender, and body mass index. Follow-up duration, indication for surgery, and patient reported outcome measures relating to patient satisfaction were also recorded.

RESULTS

There were a total of 5234 patients and 5288 shoulders from the 45 included studies. The overall study population was 61.2% female and the average age was 71.1 years (range 23-99). Satisfaction results were recorded at final follow-up, with average follow-up of 49.1 months (range 24-228). Overall patient satisfaction ranged from 77.7% to 87.8%, depending on patient satisfaction patient reported outcome measures. When stratified by diagnosis, patients with a diagnosis of glenohumeral osteoarthritis (GHOA) rated better satisfaction on all metrics when compared to patients with a diagnosis of cuff tear arthropathy or massive rotator cuff tear.

CONCLUSION

This systematic review demonstrated that patients who undergo rTSA for either GHOA, cuff tear arthropathy, or massive rotator cuff tear are generally satisfied with their procedure, with the rate of satisfaction highest in GHOA. Focusing on patient satisfaction may provide the best overall assessment of health care quality in a very understandable and tangible form. Overall satisfaction rate is valuable information for patient education and can be utilized as part of effective surgical counseling.

Clinical outcomes of anatomic vs. reverse total shoulder arthroplasty in primary osteoarthritis with preoperative external rotation weakness and an intact rotator cuff: a case-control study

BACKGROUND

Anatomic (aTSA) and reverse total shoulder arthroplasty (rTSA) are well-established treatments for patients with primary osteoarthritis and an intact cuff. However, it is unclear whether aTSA or rTSA provides superior outcomes in patients with preoperative external rotation (ER) weakness.

METHODS

A retrospective review of a prospectively collected shoulder arthroplasty database was performed between 2007 and 2020. Patients were excluded for preoperative diagnoses of nerve injury, infection, tumor, or fracture. The analysis included 333 aTSAs and 155 rTSAs performed for primary cuff-intact osteoarthritis with 2-year minimum follow-up. Defining preoperative ER weakness as strength <3.3 kilograms (7.2 pounds), 3 cohorts were created and matched: (1) weak aTSAs (n = 74) vs. normal aTSAs (n = 74), (2) weak rTSAs (n = 38) vs. normal rTSAs (n = 38), and (3) weak rTSAs (n = 60) vs. weak aTSAs (n = 60). We compared range of motion, outcome scores, strength, complications, and revision rates at the latest follow-up.

RESULTS

Despite weak aTSAs having poorer preoperative strength in forward elevation and ER (P < .001), neither of these deficits persisted postoperatively compared with the normal cohort. Likewise, weak rTSAs had poorer preoperative strength in forward elevation and ER, overhead motion, and Constant, Shoulder Pain and Disability Index, and University of California, Los Angeles scores (P < .029). However, no statistically significant differences were found between preoperatively weak and normal rTSAs. When comparing weak aTSA vs. weak rTSA, no differences were found in preoperative and postoperative outcomes, proportion of patients achieving the minimal clinically important difference and substantial clinical benefit, and complication and rate of revision surgery.

CONCLUSIONS

In preoperatively weak patients with cuff-intact primary osteoarthritis, aTSA leads to similar postoperative strength, range of motion, and outcome scores compared with patients with normal preoperative strength, indicating that preoperative weakness does not preclude aTSA use. Furthermore, patients who were preoperatively weak in ER demonstrated improved postoperative rotational motion after undergoing aTSA and rTSA, with both groups achieving the minimal clinically important difference and substantial clinical benefit at similar rates.

Total shoulder arthroplasty in patients with factor V Leiden

BACKGROUND

Anatomic and reverse total shoulder arthroplasty (TSA) are effective treatment options for end-stage glenohumeral osteoarthritis. However, consideration for pre-existing conditions must be taken into account. Factor V Leiden (FVL), the most common inherited thrombophilia, is one such condition that predisposes to a prothrombotic state and may affect perioperative and longer-term outcomes following TSA.

METHODS

Adult patients undergoing primary TSA for osteoarthritis indication were identified in the 2010 through October 2021 PearlDiver M157 database. Patients with or without FVL were matched at a 1:4 ratio based on age, sex, and Elixhauser Comorbidity Index. Ninety-day adverse events and 5-year revision rates were assessed and compared with multivariable logistic regression and rank-log tests, respectively. Finally, the relative use and bleeding/clotting outcomes were assessed based on venous thromboembolic (VTE) prophylactic agents used, with categories defined as (1) warfarin, heparin, or direct oral anticoagulant (DOAC) or (2) aspirin/no prescription found.

RESULTS

Of 104,258 TSA patients, FVL was identified for 283 (0.27%). Based on matching, 1081 patients without FVL and 272 patients with FVL were selected. Multivariable analyses demonstrated that those with FVL displayed independently greater odds ratios (ORs) of deep vein thrombosis (DVT, OR = 9.50, P < .0001), pulmonary embolism (PE, OR = 10.10, P < .0001), and pneumonia (OR = 2.43, P = .0019). Further, these events contributed to the increased odds of aggregated minor (OR = 1.95, P = .0001), serious (OR = 6.38, P < .0001), and all (OR = 3.51, P < .0001) adverse events. All other individual 90-day adverse events, as well as 5-year revision rates, were not different between the study groups. When compared to matched patients without FVL on the same anticoagulant agents, FVL patients on warfarin, heparin, or DOAC agents demonstrated lesser odds of 90-day DVT and PE (OR = 4.25, P < .0001, and OR = 2.54, P = .0065) than those on aspirin/no prescription found (OR = 7.64 and OR = 21.95, P < .0001 for both). Interestingly, those on VTE prophylactic agents were not at greater odds of bleeding complications (hematoma or transfusion).

DISCUSSION AND CONCLUSIONS

TSA patients with FVL present a difficult challenge to shoulder reconstruction surgeons. The current study highlights the strong risk of VTE that was reduced but still significantly elevated for those with stronger classes of VTE chemoprophylaxis. Acknowledging this risk is important for surgical planning and patient counseling, but also noted was the reassurance of similar 5-year revision rates for those with vs. without FVL.

Anatomic versus reverse total shoulder arthroplasty outcomes after prior contralateral anatomic total shoulder arthroplasty in patients with bilateral primary osteoarthritis with an intact rotator cuff

PURPOSE

We aimed to compare outcomes in patients that underwent bilateral anatomic total shoulder arthroplasty (aTSA) vs. aTSA/ reverse total shoulder arthroplasty (rTSA) for rotator cuff-intact glenohumeral osteoarthritis (RCI-GHOA) to further elucidate the role of rTSA in this patient population.

METHODS

A single-institution prospectively collected shoulder arthroplasty database was reviewed for patients undergoing bilateral total shoulder arthroplasty (TSA) for RCI-GHOA with a primary aTSA and subsequent contralateral aTSA or rTSA. Outcome scores (SPADI, SST, ASES, UCLA, Constant) and active range of motion (abduction, forward elevation [FE], external and internal rotation [ER and IR]) were evaluated. Clinically relevant benchmarks (minimal clinically important difference [MCID], substantial clinical benefit [SCB], and patient acceptable symptomatic state [PASS]) were evaluated against values in prior literature. Incidence of surgical complications and revision rates were examined in qualifying patients as well as those without 

RESULTS

Of the 55 bilateral TSA patients with an intact rotator cuff, 46 underwent aTSA/aTSA and 9 underwent aTSA/rTSA. At the time of the second TSA, patients undergoing aTSA/rTSA were older (71 ± 4 vs. 67 ± 7, P = .032) and more commonly had inflammatory arthritis (44% vs. 11%, P = .031). Mean time to the second TSA was shorter for aTSA/aTSA (2.3 ± 2.8 vs. 4.4 ± 3.6 years, P < .001). Postoperative outcomes were similar after the first aTSAs between groups with similar proportions achieving the MCID, SCB, and PASS (all P > .05). The 2nd TSAs between groups were similar preoperatively, but aTSA/rTSA had superior outcome scores, overhead motion, and active abduction compared to patients that underwent aTSA/aTSA. There were no differences in active ER and IR scores or complication rates between groups.

CONCLUSION

Patients with RCI-GHOA have excellent clinical outcomes after either aTSA/aTSA or aTSA/rTSA.

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Key Words

• Clinical outcome
• Inflammatory arthritis, Rotator cuff
• Reverse shoulder arthroplasty
• Shoulder replacement

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MESH Headings

• Humans
• Arthroplasty, Replacement, Shoulder/adverse effects
• Rotator Cuff/surgery
• Shoulder Joint/surgery
• Treatment Outcome
• Retrospective Studies
• Osteoarthritis/surgery
• Osteoarthritis/etiology
• Range of Motion, Articular

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Affiliation(s)

Lacie M Turnbull Department of Orthopaedic Surgery and Sports Medicine, Orthopaedics and Sports Medicine Institute, 3450 Hull Road, University of Florida, Gainesville, FL, 32611, USA
Kevin A Hao College of Medicine, University of Florida, Gainesville, FL, USA
Victoria E Bindi College of Medicine, University of Florida, Gainesville, FL, USA
Jonathan O Wright Department of Orthopaedic Surgery and Sports Medicine, Orthopaedics and Sports Medicine Institute, 3450 Hull Road, University of Florida, Gainesville, FL, 32611, USA
Thomas W Wright Department of Orthopaedic Surgery and Sports Medicine, Orthopaedics and Sports Medicine Institute, 3450 Hull Road, University of Florida, Gainesville, FL, 32611, USA
Kevin W Farmer Department of Orthopaedic Surgery and Sports Medicine, Orthopaedics and Sports Medicine Institute, 3450 Hull Road, University of Florida, Gainesville, FL, 32611, USA
Terrie Vasilopoulos Department of Orthopaedic Surgery and Sports Medicine, Orthopaedics and Sports Medicine Institute, 3450 Hull Road, University of Florida, Gainesville, FL, 32611, USA Department of Anesthesiology, University of Florida, Gainesville, FL, USA
Aimee M Struk Department of Orthopaedic Surgery and Sports Medicine, Orthopaedics and Sports Medicine Institute, 3450 Hull Road, University of Florida, Gainesville, FL, 32611, USA
Bradley S Schoch Department of Orthopaedic Surgery, Mayo Clinic, Jacksonville, FL, USA
Joseph J King Department of Orthopaedic Surgery and Sports Medicine, Orthopaedics and Sports Medicine Institute, 3450 Hull Road, University of Florida, Gainesville, FL, 32611, USA.

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Clinical outcomes of anatomical versus reverse total shoulder arthroplasty in patients with primary osteoarthritis, an intact rotator cuff, and limited forward elevation

Aims

Both anatomical and reverse total shoulder arthroplasty (aTSA and rTSA) provide functional improvements. A reported benefit of aTSA is better range of motion (ROM). However, it is not clear which procedure provides better outcomes in patients with limited foward elevation (FE). The aim of this study was to compare the outcome of aTSA and rTSA in patients with glenohumeral osteoarthritis (OA), an intact rotator cuff, and limited FE.

Methods

This was a retrospective review of a single institution's prospectively collected shoulder arthroplasty database for TSAs undertaken between 2007 and 2020. A total of 344 aTSAs and 163 rTSAs, which were performed in patients with OA and an intact rotator cuff with a minimum follow-up of two years, were included. Using the definition of preoperative stiffness as passive FE ≤ 105°, three cohorts were matched 1:1 by age, sex, and follow-up: stiff aTSAs (85) to non-stiff aTSAs (85); stiff rTSAs (74) to non-stiff rTSAs (74); and stiff rTSAs (64) to stiff aTSAs (64). We the compared ROMs, outcome scores, and complication and revision rates.

Results

Compared with non-stiff aTSAs, stiff aTSAs had poorer passive FE and active external rotation (ER), whereas there were no significant postoperative differences between stiff rTSAs and non-stiff rTSAs. There were no significant differences in preoperative function when comparing stiff aTSAs with stiff rTSAs. However, stiff rTSAs had significantly greater postoperative active and passive FE (p = 0.001 and 0.004, respectively), and active abduction (p = 0.001) compared with stiff aTSAs. The outcome scores were significantly more favourable in stiff rTSAs for the Shoulder Pain and Disability Index, Simple Shoulder Test, American Shoulder and Elbow Surgeons score, University of California, Los Angeles score, and the Constant score, compared with stiff aTSAs. When comparing the proportion of stiff aTSAs versus stiff rTSAs that exceeded the minimal clinically important difference and substantial clinical benefit, stiff rTSAs achieved both at greater rates for all measurements except active ER. The complication rate did not significantly differ between stiff aTSAs and stiff rTSAs, but there was a significantly higher rate of revision surgery in stiff aTSAs (p = 0.007).

Conclusion

Postoperative overhead ROM, outcome scores, and rates of revision surgery favour the use of a rTSA rather than aTSA in patients with glenohumeral OA, an intact rotator cuff and limited FE, with similar rotational ROM in these two groups.

Similar rates of revision surgery following primary anatomic compared with reverse shoulder arthroplasty in patients aged 70 years or older with glenohumeral osteoarthritis: a cohort study of 3791 patients

BACKGROUND

Reverse total shoulder arthroplasty (RTSA), initially indicated for cuff tear arthropathy, is increasingly used to treat elderly patients with primary glenohumeral osteoarthritis (GHOA) and an intact rotator cuff. This is often done to avoid revision surgery in elderly patients for rotator cuff failure with anatomic total shoulder arthroplasty (TSA) despite traditionally good outcomes of TSA. We sought to determine whether there was a difference in outcomes in patients aged ≥70 years who received RTSA vs. TSA for GHOA.

METHODS

A retrospective cohort study was conducted using data from a US integrated health care system's shoulder arthroplasty registry. Patients aged ≥70 years who underwent primary shoulder arthroplasty for GHOA with an intact rotator cuff were included (2012-2021). RTSA was compared with TSA. Multivariable Cox proportional hazard regression was used to evaluate all-cause revision risk during follow-up, whereas multivariable logistic regression was used to evaluate 90-day emergency department (ED) visits and 90-day readmissions.

RESULTS

The final study sample comprised 685 RTSA patients and 3106 TSA patients. The mean age was 75.8 years (standard deviation, 4.6 years), and 43.4% of patients were men. After accounting for confounders, we observed no significant difference in all-cause revision risk for RTSA vs. TSA (hazard ratio, 0.79; 95% confidence interval [CI], 0.39-1.58). The most common reason for revision following RTSA was glenoid component loosening (40.0%). Over half of revisions following TSA were for rotator cuff tear (54.0%). No difference based on procedure type was observed in the likelihood of 90-day ED visits (odds ratio, 0.94; 95% CI, 0.71-1.26) and 90-day readmissions (odds ratio, 1.32; 95% CI, 0.83-2.09).

CONCLUSION

RTSA and TSA for GHOA with an intact rotator cuff in patients aged ≥70 years had a similar revision risk, as well as a similar likelihood of 90-day ED visits and readmissions. Although revision risk was similar, the most common causes of revision were different, with rotator cuff tears in TSA patients and glenoid component loosening in RTSA patients.

How common is nerve injury after reverse shoulder arthroplasty? A systematic review

BACKGROUND

Nerve injury following reverse shoulder arthroplasty (RSA) is a known risk factor with wide ranging incidences reported. This systematic review evaluates the overall incidence of nerve injury following primary and revision RSA and summarizes the characteristics of the nerve injuries reported in the current literature.

METHODS

A systematic review was performed using separate database searches (Pubmed, Embase, Web of Science, Cochrane) following the PRISMA guidelines. Search criteria included the title terms "reverse shoulder," "reverse total shoulder," "inverted shoulder," and "inverted total shoulder" with publication dates ranging from 01/01/2010 to 01/01/2022. Studies that reported neurological injuries and complications were included and evaluated for primary RSA, revision RSA, number of nerve injuries, and which nerves were affected.

RESULTS

After exclusion, our systematic review consisted of 188 articles. A total of 40,146 patients were included, with 65% female. The weighted mean age was 70.3 years. The weighted mean follow-up was 35.4 months. The rate of nerve injury after RSA was 1.3% (510 of 40,146 RSAs). The rate of injury was greater in revision RSA compared to primary RSA (2.4% vs. 1.3%). Nerve injury was most common in RSAs done for a primary diagnosis of acute proximal humerus fracture (4.0%), followed by cuff tear arthropathy (3.0%), DJD (2.6%), and inflammatory arthritis (1.7%). Massive rotator cuff tears and post-traumatic arthritis cases had the lowest nerve injury rates (1.0% and 1.4%, respectively). The axillary nerve was the most commonly reported nerve that was injured in both primary and revision RSA (0.6%), followed by the ulnar nerve (0.26%) and median nerve (0.23%). Brachial plexus injury was reported in 0.19% of overall RSA cases.

CONCLUSION

Based on current English literature, nerve injuries occur at a rate of 1.3% after primary RSA compared with 2.4% after revision RSA. The most common nerve injury was to the axillary nerve (0.64%), with the most common operative diagnosis associated with nerve injury after RSA being acute proximal humerus fracture (4.0%). Surgeons should carefully counsel patients prior to surgery regarding the risk of nerve injury.

Primary reverse total shoulder arthroplasty performed for glenohumeral arthritis: does glenoid morphology matter?

BACKGROUND

Indications for reverse total shoulder arthroplasty (RTSA) have expanded to include primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff. Limited evidence exists on RTSA in patients with primary GHOA and no posterior glenoid wear (Walch A1, A2, and B1 morphologies). The purpose of this retrospective cohort study was to determine if glenoid morphology is associated with clinical outcomes in patients undergoing RTSA for primary GHOA.

METHODS

A retrospective review of prospectively collected data was performed in patients undergoing primary RTSA for GHOA with a minimum of 2-year clinical follow-up. Preoperative computed tomography and magnetic resonance imaging were used to categorize glenoid morphology as described by the modified Walch classification. Pre- and postoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Single Assessment Numeric Evaluation (SANE), visual analog scale (VAS) pain scores, and range of motion (ROM) measurements were compared across Walch glenoid subtypes. The percentage of patients that reached previously established clinically significant thresholds for minimal clinically important difference (MCID) and substantial clinical benefit (SCB) was also comparatively assessed. Multivariable analysis was used to evaluate the association between glenoid morphology and postoperative ASES score while controlling for potentially confounding variables.

RESULTS

Of the 247 consecutive patients, 197 were available at a minimum 2-year follow-up (80%). Significant improvements were seen in ASES, VAS pain, SANE, and ROM from baseline to final postoperative follow-up in the combined patient cohort (all P < .001). Most (98.0%) patients reached MCID, and 90.9% of patients reached SCB for ASES threshold. No significant differences were found among Walch subtypes in terms of preoperative to postoperative improvement in ASES (P = .39), SANE (P = .4), VAS pain (P = .49), forward elevation (P = .77), external rotation (P = .45), or internal rotation (P= 0.1). The only significant difference in postoperative outcomes between Walch glenoid subtypes was higher postoperative ASES scores among type B3 glenoids compared with type A1 glenoids (P = .03) on univariate analysis. However, no individual Walch glenoid subtype was associated with lower postoperative ASES scores on multivariable analysis (P > .05).

CONCLUSION

Primary RTSA provides excellent short-term outcomes in patients with glenohumeral arthritis with intact rotator cuff, regardless of the degree of preoperative glenoid deformity. Surgeons can use these data to support the use of RTSA for glenohumeral arthritis in a more standardized way.

Predictors of poor and excellent outcomes after reverse total shoulder arthroplasty

BACKGROUND

Favorable clinical and functional outcomes can be achieved with reverse total shoulder arthroplasty (RSA). Given the expanding utilization of RSA in the United States, understanding the factors that influence both excellent and poor outcomes is increasingly important.

METHODS

A single-surgeon prospective registry was used to identify patients who underwent RSA from 2015 to 2018 with a minimum of 2 years' follow-up. An excellent postoperative clinical outcome was defined as a final American Shoulder and Elbow Surgeons (ASES) score in the top quartile of ASES scores. A poor outcome was defined as an ASES score in the bottom quartile. Logistic regression was used to determine preoperative characteristics associated with both excellent and poor outcomes.

RESULTS

A total of 338 patients with a mean age of 71.5 years (standard deviation [SD], 6.4 years) met the inclusion and exclusion criteria. The average preoperative ASES score for the entire cohort was 35.3 (SD, 16.4), which improved to 82.4 (SD, 16.1) postoperatively (P < .001). Univariate analysis demonstrated that a diagnosis of primary osteoarthritis (OA), private insurance, and higher preoperative ASES scores were significantly associated with achieving excellent outcomes (P < .01 for all). Variables predictive of poor outcomes were workers' compensation status (P = .03), depression (P = .02), a preoperative diagnosis of rotator cuff tear arthropathy (P < .01), preoperative opioid use (P < .01), a higher number of allergies (P < .01), and prior ipsilateral shoulder surgery (P < .01). Multivariate regression analysis demonstrated that OA (odds ratio [OR], 5.6; 95% confidence interval [CI], 1.2-26.5; P = .03) and private insurance (OR, 2.7; 95% CI, 1.12-6.5; P = .02) correlated with excellent outcomes whereas a higher number of reported allergies (OR, 0.83; 95% CI, 0.71-0.97; P = .02), self-reported depression (OR, 0.39; 95% CI, 0.16-0.99; P =.04), a history of ipsilateral shoulder surgery (OR, 0.36; 95% CI, 0.15-0.87; P =.02), and preoperative opioid use (OR, 0.26; 95% CI, 0.09-0.76; P = .01) were predictive of poor outcomes.

CONCLUSIONS

A preoperative diagnosis of primary OA is the strongest predictor of excellent clinical outcomes following RSA. Patients with an increasing number of reported allergies, self-reported depression, a history of ipsilateral shoulder surgery, and preoperative opioid use are significantly more likely to achieve poor outcomes after RSA. Given the increasing utilization of RSA, this information is important to appropriately counsel patients regarding postoperative expectations.

Is reverse total shoulder arthroplasty (rTSA) more advantageous than anatomic TSA (aTSA) for osteoarthritis with intact cuff tendon? A systematic review and meta-analysis

PURPOSE

We aimed to compare the outcomes and complications of anatomical shoulder arthroplasty (aTSA) and reverse total shoulder arthroplasty (rTSA) for primary glenohumeral osteoarthritis with intact cuff tissue.

MATERIALS AND METHODS

The MEDLINE, Embase, and Cochrane Library databases were systematically searched for studies published before March 2, 2021 using the PRISMA guidelines. Studies were included if they directly compared aTSA and rTSA for treating primary glenohumeral arthritis. A meta-analysis was performed using six studies that compared radiologic outcomes, functional scores, and range of motion (ROM). All the data were pooled using a random-effects model. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated as dichotomous data, while continuous data were analyzed using mean differences with 95% CIs.

RESULTS

Two independent researchers reviewed 1,061 studies. Six studies met the inclusion criteria. The range of motion, especially external rotation, was better for aTSA than for rTSA (MD = - 10.28, 95% CI: - 16.69 to - 3.88, P = 0.002). Functional scores showed no difference between aTSA and rTSA. Glenoid loosening (OR = 0.17, 95% CI: 0.06-0.50, P = 0.001) was more common with aTSA, and scapula notching (OR = 10.63, 95% CI: 1.73-65.27, P = 0.01) with rTSA. In the mid-term follow-up, the overall revision rate showed no difference between aTSA and rTSA, with a pooled OR of 0.33 (95% CI: 0.07-1.57, P = 0.16).

CONCLUSION

A better ROM was achieved after aTSA than after rTSA. There was no difference in the revision rate at mid-term follow-up between aTSA and rTSA. Glenoid loosening was more common with aTSA, and scapula notching with rTSA.

LEVEL OF EVIDENCE

Level IV, Meta-analysis.

Rate of improvement in shoulder strength after anatomic and reverse total shoulder arthroplasty

Background

Methods

Results

Conclusion

Clinical outcomes of anatomic total shoulder arthroplasty for primary shoulder osteoarthritis did not differ between elderly and younger Japanese patients

Background

Few studies on the outcomes of anatomic total shoulder arthroplasty (aTSA) in Asian populations have been reported. In addition, approximately one-third of primary aTSA were performed for patients 80 years or older in Japan, but the indication of aTSA for the primary shoulder osteoarthritis in the elderly population remained unclear. The purposes of this study were (1) to investigate clinical outcomes of aTSA in Japanese patients with primary glenohumeral osteoarthritis and (2) to compare clinical outcomes between patients 80 years or older and 70 years or younger. We hypothesized that aTSA would yield favorable outcomes in Japanese patients and that the outcomes of aTSA in patients 80 years or older would be comparable to those 70 years or younger.

Methods

Patient records were retrospectively reviewed to collect patients who underwent aTSA for glenohumeral osteoarthritis between August 2011 and September 2017. The inclusion criterion of this study was aTSA performed for glenohumeral osteoarthritis. Exclusion criteria were as follows: (1) secondary osteoarthritis, (2) revision surgery, and (3) < 24-month follow-up. Range of motion (ROM) and Constant score were evaluated, and complications were investigated. Rotator cuff integrity was assessed by ultrasonography. We compared the outcomes between patients 80 years or older and 70 years or younger.

Results

Seventy-seven shoulders (72 patients) met the study criteria. There were 14 men and 58 women with a mean age of 75 years (range, 57-93 years) at the time of surgery. The mean follow-up was 40 months (range, 24-84 months). The Constant score significantly improved from preoperative 54 (range, 35-78) to postoperative 89 (range 69-100, P = .03). Range of motion also showed significant improvement after surgery: flexion, 90° (range, 60°-130°) to 140° (range, 90°-170°); external rotation at the side, from 7° (range, -10 to 60°) to 40° (range, 5°-70°); internal rotation, from buttock (range, buttock-L3) to L2 level (range, buttock-T8) (P <.001 for all). Postoperative subscapularis tendon tears were detected in 3 shoulders (5%). Complications other than rotator cuff tears were observed in 5 shoulders (6%). Postoperative Constant score and ROM significantly improved in both elderly and younger patients without significant differences.

Conclusion

The clinical outcomes after aTSA in the Japanese population demonstrated significant improvements in ROM and Constant score with a low complication rate in the mid-term follow-up. aTSA should be indicated even in elderly patients because they also demonstrated comparable outcomes to younger patients.

Postoperative malrotation of humerus shaft fracture causes degeneration of rotator cuff and cartilage

We hypothesized that postoperative malrotation of humeral shaft fractures can alter the bio-mechanical environment of the shoulder; thus, rotator cuff and cartilage degeneration could be induced. Therefore, we designed an animal experiment to evaluate the impact of malrotation deformities after minimally invasive surgery for humeral fractures on the rotator cuff and cartilage, which has rarely been described in previous studies. Twenty-four New Zealand white rabbits were randomly divided into the sham control group (A), negative control group (B) and malrotated group (C). A sham operation with surgical exposure alone was performed in group A. Humeral shaft osteotomy was performed in Group B and C. In Group B, the fractures were fixed in situ with plate -screw system. While in Group C, iatrogenic rotational deformity was created after the proximal end of the fracture being internally rotated by 20 degrees and then subsequently fixed. The animals with bone healing were sacrificed for pathological and biochemical examination. In group C, the modified Mankin scale for cartilage pathology evaluation and the modified Movin scale for tendon both showed highest score among groups with statistical significance (P < 0.05); Disordered alignment and proportion of collagen I/III of rotator cuff were confirmed with picrosirius red staining; Transmission electron microscopy also showed ultrastructural tendon damage. Immunohistochemistry showed that both MMP-1 and MMP-13 expression were significantly higher in group C than groups A and B(P < 0.05). Minimally invasive techniques for humerus shaft fracture might be cosmetically advantageous, but the consequent postoperative malrotation could increase the risk of rotator cuff and cartilage degeneration. This conclusion is supported here by primary evidence from animal experiments.