Bilateral Anatomic Total Shoulder Arthroplasty Versus Reverse Shoulder Arthroplasty

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1 Bilateral Anatomic Total Shoulder Arthroplasty Versus Reverse Shoulder Arthroplasty Vaqar Latif, MD; Patrick J. Denard, MD; Allan A. Young, MD; Jean-Pierre Liotard, MD; Gilles Walch, MD abstract Full article available online at Healio.com/Orthopedics. Search: The results of anatomic total shoulder arthroplasty and reverse shoulder arthroplasty have previously been reported separately. Although the indications differ, scenarios exist in which a patient may have a total shoulder arthroplasty on 1 shoulder and a reverse shoulder arthroplasty on the contralateral shoulder. A Between 1992 and 2009, twelve patients underwent bilateral sequential primary shoulder arthroplasty with a total shoulder arthroplasty on 1 side and reverse shoulder arthroplasty on the contralateral side. Constant score, American Shoulder and Elbow Surgeons (ASES) score, subjective shoulder value, and patient satisfaction were obtained a minimum 1 year postoperatively. Mean postoperative Constant score was 77 after total shoulder arthroplasty and 73 after reverse shoulder arthroplasty (P,.2488). Mean postoperative active forward flexion was similar after total shoulder arthroplasty compared with reverse shoulder arthroplasty (P5.8910). Greater external rotation at the side (43 vs 12 ; P,.0001) and internal rotation (T8 vs L1; P,.0001) were observed after total shoulder arthroplasty. Mean ASES score was 89.6 after total shoulder arthroplasty compared with 82.4 after reverse shoulder arthroplasty (P5.0125). Patient satisfaction was 92% for both prostheses, and mean subjective shoulder value was similar (85.4% vs 82.5%; P5.6333). Bilateral shoulder arthroplasty performed with a total shoulder arthroplasty and reverse shoulder arthroplasty on opposite shoulders can provide good functional outcome and high patient satisfaction. Although range of motion is better following total shoulder arthroplasty, no difference was observed in final Constant score or subjective patient assessment. Figure: Pre- (A) and postoperative (B) radiographs of anatomic total shoulder arthroplasty (left) and reverse shoulder arthroplasty (right). B Drs Latif, Liotard, and Walch are from Centre Orthopédique Santy, Lyon, France; Dr Denard is from Southern Oregon Orthopedics, Medford, and the Department of Orthopaedics and Rehabilitation, Oregon Health & Science University, Portland, Oregon; and Dr Young is from Sydney Shoulder Specialists, Sydney, New South Wales, Australia. Drs Latif, Denard, Young, and Liotard have no relevant financial relationships to disclose. Dr Walch is a consultant for and receives inventor royalties from Tornier, Inc. Correspondence should be addressed to: Patrick J. Denard, MD, Southern Oregon Orthopedics, 2780 E Barnett Rd, Ste 200, Medford, OR (pjdenard@gmail.com). doi: / e479

2 Various prosthetic options exist in the surgical management of conditions that affect the glenohumeral joint. In the older adult population, anatomic total shoulder arthroplasty and reverse shoulder arthroplasty are the 2 most common prosthetic options for resurfacing of the humerus and the glenoid. Conventional anatomic (nonconstrained) total shoulder arthroplasty is indicated for glenohumeral conditions in which the rotator cuff is intact and adequate glenoid bone stock exists to implant a polyethylene glenoid. The most common indications are primary osteoarthritis, posttraumatic osteoarthritis, and avascular necrosis. 1-3 A constrained reverse shoulder arthroplasty prosthesis is most commonly indicated in the setting of rotator cuff tear arthropathy but may also be used for pseudoparalysis with an irreparable rotator cuff tear or posterior glenoid instability that prevents implantation of an unconstrained glenoid. 4-6 The outcomes of these 2 arthroplasty types have previously been reported separately. Two studies reported the clinical outcomes of bilateral total shoulder arthroplasty in the same patient. 7,8 However, to our knowledge, no published studies compare total shoulder arthroplasty and reverse shoulder arthroplasty in the same patient. While the indications for these 2 prostheses differ, with the increase in shoulder arthroplasty in recent years, 9 particularly that of the reverse shoulder arthroplasty, scenarios exist in which an individual may have a total shoulder arthroplasty on 1 shoulder and an reverse shoulder arthroplasty on the contralateral shoulder. This specific patient population provides a unique opportunity to directly compare the outcomes of total shoulder arthroplasty and reverse shoulder arthroplasty. The purpose of this study was to compare the functional outcome, patient satisfaction, and perioperative complications associated with total shoulder arthroplasty and reverse shoulder arthroplasty in a Figure 1: Pre- (A) and postoperative (B) radiographs of anatomic total shoulder arthroplasty (left) and reverse shoulder arthroplasty (right). group of patients who underwent total shoulder arthroplasty on 1 shoulder and reverse shoulder arthroplasty on the other. The hypothesis of this study was that postoperative range of motion (ROM) would be different between total shoulder arthroplasty and reverse shoulder arthroplasty but that patient satisfaction would be similar. Materials and Methods A retrospective review was conducted of shoulder arthroplasties performed between April 1992 and March 2009 at a single institution by a single surgeon (G.W.). Inclusion criteria were a staged bilateral shoulder arthroplasty with a total shoulder arthroplasty on 1 shoulder, a reverse shoulder arthroplasty on the other shoulder, and a minimum 1-year followup for each shoulder. Exclusion criteria were any other prosthetic combination (eg, hemiarthroplasty for either shoulder) and either arthroplasty performed initially as a revision surgery. Surgical Technique All surgeries were performed by the senior author (G.W.). The surgical approach has been previously described. 1 A standard deltopectoral approach was used in every case, except in 1 case of reverse shoulder arthroplasty in which the superolateral approach was performed. 10,11 The subscapularis tendon was tenotomized at the anatomical neck of humerus. Osteotomy 1A 1B of the humeral head was performed at the same level after having removed osteophytes. All anatomic total shoulder arthroplasties were performed with the same prosthesis (Aequalis Shoulder System; Tornier, Inc, Montbonnot, France), using a cemented keeled all-polyethylene glenoid component and a cemented humeral component (Figure 1). All but 2 reverse shoulder arthroplasties were performed with the Aequalis Reverse System (Tornier, Inc) (Figure 1). The remaining 2 were performed with the Delta III reverse system (DePuy Orthopedics France, Saint Priest, France). Both reverse shoulder arthroplasty prosthesis types are based on the Grammont design with a fixed medialized center of rotation. 1 The humeral stem was cemented in all cases. The subscapularis tenotomy was repaired at the conclusion of the procedure with transosseous nonresorbable sutures. The biceps tendon was tenodesed to the upper margin of the pectoralis major tendon. Rehabilitation Postoperatively, all patients were instructed to wear a sling for 4 weeks, except when performing physical therapy. Rehabilitation with self-mobilization in elevation and external rotation was allowed from postoperative day 3, immediately followed by self-mobilization in a heated swimming pool with a trained physical therapist who supervised the rehabilitation. Six weeks postoperatively, usual ac- e480 Healio.com The new online home of ORTHOPEDICS Healio.com/Orthopedics

3 Bilateral Shoulder Arthroplasty Latif et al tivities of daily living were allowed, and self-mobilization in elevation and external rotation were continued. Three months postoperatively, the patient was allowed to progressively resume resistive activities and conditioning exercises (eg, jogging, cycling, and swimming) with no strengthening exercise for the upper limbs. Postoperative Clinical Assessment Pre- and postoperative ROM (active forward flexion, external rotation with the arm at the side, external rotation with the arm at 90 of abduction, and internal rotation behind the back), Constant scores 12 and subjective shoulder values 13 were prospectively collected annually by an independent examiner who was not involved in the surgery (J.L.). All patients also participated in a telephone interview by a second examiner (V.L.) to establish the American Shoulder and Elbow Surgeons (ASES) score 14,15 and the overall satisfaction with the surgery outcome (disappointed, uncertain, satisfied, or very satisfied). In addition, the patients were asked to respond to the following questions: (1) Do you prefer 1 shoulder to the other, and if so, which shoulder do you prefer?; and (2) On which side was the postoperative rehabilitation easier? Statistical Methods Pre- and postoperative Constant and ASES scores and ROM values were compared with paired-samples t test when the comparison was done in the same shoulder, and independent-samples t test when the comparison was done between the shoulders for total shoulder arthroplasty and reverse shoulder arthroplasty. For purposes of analysis, satisfaction was collapsed into yes (satisfied or very satisfied) or no (uncertain or disappointed), and proportions were analyzed with Fisher s exact test. Statistical analysis was performed by a trained statistician using MedCalc version (MedCalc Software, Mariakerke, Belgium). Statistical significance was set at P,.05. Results A total of 1136 total shoulder arthroplasties and 534 reverse shoulder arthroplasties were performed during the study period. Sixteen patients underwent bilateral shoulder arthroplasty. Three of the 16 patients were excluded: 2 patients had undergone a reverse shoulder arthroplasty in combination with a hemiarthroplasty and 1 patient underwent a reverse shoulder arthroplasty as a revision. One patient was deceased and had incomplete follow-up data. Twelve patients (10 women and 2 men) met the study criteria. The prosthesis on the dominant extremity was a total shoulder arthroplasty in 3 patients (25.0%) and a reverse shoulder arthroplasty in 9 patients (75.0%). Mean patient age at total shoulder arthroplasty was years (range, years), and mean patient age at reverse shoulder arthroplasty was years (range, years). Mean duration of clinical follow-up examination was years (range, 2-13 years) for the total shoulder arthroplasty group and years (range, 1-11 years) for the reverse shoulder arthroplasty group. The telephone interview took place a mean of years (range, 2-13 years) postoperatively in the total shoulder arthroplasty group and (range, 1-11 years) years postoperatively in the reverse shoulder arthroplasty group. Indications for total shoulder arthroplasty included 9 cases of primary osteoarthritis and 1 case each of rheumatoid arthritis with an intact rotator cuff, avascular necrosis, and posttraumatic arthritis. Indications for reverse shoulder arthroplasty included 11 cases of cuff tear arthropathy, 1 case of avascular necrosis with glenoid deformity that prevented insertion of an unconstrained glenoid component, and 1 case of rheumatoid arthritis with a rotator cuff tear. Mean time between the 2 surgeries was 2.8 years (range, 1-11 years); total shoulder arthroplasty was performed prior to reverse shoulder arthroplasty in 10 patients. Mean Constant score improved from 27.9 points preoperatively to 76.8 points postoperatively at final follow-up (148.9; P,.0001) for the total shoulder arthroplasty side and from 35.5 to 72.6 points (137.1; P,.0001) for the reverse shoulder arthroplasty side. For the total shoulder arthroplasty side, ROM improved in all planes. Forward flexion improved from preoperatively to postoperatively (157.5 ; P5.0008). External rotation at the side improved from preoperatively to postoperatively (140.0 ; P,.0001), and external rotation at 90 of abduction improved from to (129.5 ; P5.0142). Internal rotation improved by 10 spinal levels from the sacrum preoperatively to T8 postoperatively (P,.0001). For the reverse shoulder arthroplasty side, only forward flexion and internal rotation improved significantly. Forward flexion improved from preoperatively to postoperatively (156.3; P5.0008). External rotation at the side was preoperatively and postoperatively (21.2; P5.8552). External rotation at 90 of abduction improved from preoperatively to postoperatively (110.8), but this difference did not reach statistical significance (P5.1059). Internal rotation improved 5 spinal levels from the sacrum preoperatively to L1 postoperatively (P,.0063). Clinical outcomes of the total shoulder arthroplasty and reverse shoulder arthroplasty sides are compared in Table 1. No difference existed in postoperative Constant scores between the 2 groups (P5.2488). However, the postoperative gain in the Constant score was significantly higher following total shoulder arthroplasty compared with reverse shoulder arthroplasty (P5.0159) (Table 1). Postoperative mean and gain in forward flexion or external rotation with the arm abducted did not vary between the 2 sides (Figures 2, 3). In contrast, postoperative e481

4 Table 1 Clinical Outcomes of Total Shoulder Arthroplasty and Reverse Shoulder Arthroplasty Postoperative Mean (Range) Mean Postoperative Gain Score TSA RSA P TSA RSA P Constant score 76.8 (64 to 85) Forward flextion, deg External rotation, deg (80 to 170) At the side 42.9 (20 to 80) At 90 abduction 54.6 (210 to 90) Internal rotation Subjective shoulder value T8 (T12 to T7) 85.4 (50 to 100) 72.6 (57 to 84) (120 to 160) 12.1 (0 to 30) 40.8 (10 to 80) L1 (sacrum to T12) 82.5 (60 to 100) , , , spinal levels 5 spinal levels, NA NA NA Abbreviations: deg, degrees; NA, not applicable; RSA, reverse shoulder arthroplasty; TSA, total shoulder arthroplasty. 2A 2B Figure 2: Clinical photographs demonstrating equal postoperative active forward flexion following reverse shoulder arthroplasty (right shoulder) (A) compared with anatomic total shoulder arthroplasty (left shoulder) (B). 3A 3C Figure 3: Clinical photographs demonstrating slighty less external rotation at 90 of abduction following reverse shoulder arthroplasty (right shoulder) (A) compared with anatomic total shoulder arthroplasty (left shoulder) (B). Figure 4: Clinical photograph demonstrating less external rotation at the side obtained following reverse shoulder arthroplasty (right shoulder) compared with anatomic total shoulder arthroplasty (left shoulder). absolute value and gain for external rotation with the arm at the side and internal rotation were greater on the total shoulder arthroplasty side compared with the reverse shoulder arthroplasty side (Figures 4, 5). Postoperative ASES score was 7.2 points higher on the total shoulder arthroplasty side compared with the reverse 4 5A 5B Figure 5: Clinical photographs demonstrating less internal rotation (mild in this case) obtained following reverse shoulder arthroplasty (right shoulder) (A) compared with anatomic total shoulder arthroplasty (left shoulder) (B). shoulder arthroplasty side (P5.0125) (Table 2). Postoperative subjective shoulder value was similar between the 2 sides (P5.6333). Patient satisfaction, prosthesis preference, and impression of the ease of rehabilitation are summarized in Table 3. Overall, 10 of 12 (83.3%) patients were satisfied or very satisfied with both prostheses; 11 of 12 (91.6%) patients were satisfied with the total shoulder arthroplasty and 11 of 12 (91.6%) patients were satisfied with the reverse shoulder arthroplasty (P51.0). Two complications occurred in this series. One anatomic total shoulder arthroplasty had an anterior dislocation 2 months postoperatively and required revision surgery. The cause of dislocation was inadequate retroversion of the humeral stem, which was corrected intraoperatively. Postoperatively, no further complications occurred. The second complication was a neuropathy of the axillary and suprascapular nerves after a reverse shoulder arthroplasty, which recovered completely after 6 months of observation. Discussion The purpose of this study was to compare the outcome of total shoulder arthro- e482 Healio.com The new online home of ORTHOPEDICS Healio.com/Orthopedics

5 Bilateral Shoulder Arthroplasty Latif et al plasty and reverse shoulder arthroplasty. Although they have both resulted in significant improvements in function and pain relief, the current study provides a direct comparison between the 2 different prosthesis types in the same patient. Previous reports have described that the functional results of total shoulder arthroplasty seem to be better than reverse shoulder arthroplasty, 4,6,19 but the procedures have not been directly compared in the same patients. In the current study, compared with preoperative values, significant improvements were observed in mean postoperative Constant scores for total shoulder arthroplasty and reverse shoulder arthroplasty. However, a greater gain in the Constant score was observed for the total shoulder arthroplasty side compared with the reverse shoulder arthroplasty side. Improvement in external rotation at the side and internal rotation were also better on the total shoulder arthroplasty side compared with the reverse shoulder arthroplasty side. This is consistent with previous studies, which show no improvement in external rotation following reverse shoulder arthroplasty. 5,20 Despite the differences in overall ROM between the 2 sides, patient satisfaction was similar between the 2 prostheses. Simovitch et al 20 reported that a lack of external rotation at the side is less compromising than a lack of external rotation at 90 of abduction in activities of daily living. Positioning of the hand in space requires forward flexion and external rotation in abduction, which could explain why the satisfaction level is similar for the 2 prostheses. In contrast to patient satisfaction, a small but statistically significant difference was observed in ASES scores between the total shoulder arthroplasty and reverse shoulder arthroplasty sides. These differences resulted from the activities of daily living section because no difference existed in pain scores between the 2 sides. Specifically, the ASES items related to internal rotation and force generation Table 2 American Shoulder and Elbow Surgeons Scores Mean ASES Component TSA Value RSA Value Difference P Activities of daily living Put on a coat Sleep on your affected side Wash back/do up bra in back Manage toileting Comb hair Reach high shelf Lift 10 lb above shoulder ,.0001 Throw a ball overhand ,.0001 Do usual work Do usual sport ,.0001 Cumulative activities of daily living score ,.0001 Pain Total ASES score Abbreviations: ASES, American Shoulder and Elbow Surgeons; RSA, reverse shoulder arthroplasty; TSA, total shoulder arthroplasty. Patient No. Dominant Extremity TSA Table 3 Patient Satisfaction Satisfaction Preferred Side Easiest Rehab 1 RSA Very satisfied Very satisfied RSA Equal 2 RSA Satisfied Very satisfied Equal TSA 3 TSA Very satisfied Very satisfied TSA TSA 4 RSA Very satisfied Very satisfied Equal Equal 5 RSA Uncertain Satisfied RSA Equal 6 RSA Very satisfied Very satisfied TSA TSA 7 RSA Very satisfied Very satisfied Equal Equal 8 TSA Very satisfied Very satisfied TSA Equal 9 TSA Very satisfied Satisfied TSA Equal 10 RSA Satisfied Uncertain TSA TSA 11 RSA Very satisfied Very satisfied Equal Equal 12 RSA Very satisfied Very satisfied RSA Equal Total 30.8% TSA 69.2% RSA RSA 91.6% satisfied 91.6% satisfied 41.7% TSA 25% RSA 33.3% equal 33.3% TSA 0% RSA 58.3% equal Abbreviations: rehab, rehabilitation; RSA, reverse shoulder arthroplasty; TSA, total shoulder arthroplasty. e483

6 (eg, throwing, sport, and lifting 10 pounds above shoulder level) favored total shoulder arthroplasty. Internal rotation and force are less effective with reverse shoulder arthroplasty than total shoulder arthroplasty because reverse shoulder arthroplasty is primarily designed to improve forward flexion. The design of reverse shoulder arthroplasty limits adduction because of the conflict between the medialized humeral component and the glenoid. 21 Reaching up behind the back requires adduction as well as internal rotation. Moreover, the lack of sufficient rotator cuff muscles in cuff tear arthropathy inherently limits external and internal rotation. However, essential activities of daily living do not involve the need to throw, play sports, or frequently lift 10 pounds above shoulder level. 22 Mean patient age for both prostheses was older than 70 years, a population that does not commonly engage in the aforementioned activities. This lower functional demand may explain why patient satisfaction in the current study remained relatively high despite poorer ASES scores. Another explanation is that pain relief carries a higher value among this population than that reflected in the ASES score distribution, which weights 50% to pain and 50% to activities. In a multivariate analysis of 70 hemiarthroplasties or total shoulder arthroplasties, Chen et al 23 reported that postoperative patient satisfaction was highly correlated with pain relief. The equal satisfaction in the current study may be related to the similar pain relief between following reverse shoulder arthroplasty or total shoulder arthroplasty. Similar to the lack of difference in patient satisfaction, patients did not clearly favor 1 type of prosthesis over the other. Although the clinical results appeared better following total shoulder arthroplasty, this did not translate into patient preference for a prosthesis type. Somewhat surprising responses were observed with regard to the relative ease of rehabilitation. In theory, postoperative rehabilitation may be easier following reverse shoulder arthroplasty because the design does not rely on rotator cuff function. However, in the current study, the majority (7/12) of patients reported no difference in rehabilitation between the 2 prosthesis types. Four of the remaining 5 patients favored the total shoulder arthroplasty side over the reverse shoulder arthroplasty side. Therefore, although it is difficult to make definitive conclusions based on these results, a slight advantage may exist in favor of rehabilitation following total shoulder arthroplasty. The lack of rotator cuff function may be more detrimental to rehabilitation than commonly appreciated. The current study had several limitations. The study design had the inherent limitations of a retrospective study. The small size also limited robust comparisons. The subjective patient responses were collected by a telephone interview, which may have influenced patient response. The major limitation was that the comparison was between 2 types of prostheses used for different etiologies. In addition, fatty infiltration of the rotator cuff, specifically that of the infraspinatus and teres minor muscles, was not compared. Fatty infiltration relates to the lack of external rotation for reverse shoulder arthroplasty. 20 The current study also had several strengths. Constant scores and clinical ROM were collected by a physician other than the operating surgeon in a standardized fashion. All surgeries were performed by a single surgeon following the same technique, thus making the results more consistent. Only primary arthroplasties of the shoulders were included to exclude patients who were predisposed to increased risk of complications associated with revision surgery. Most notably, a direct side-to-side comparison in the same patient eliminated variability that exists because of weight, sex difference, comorbidities, bone quality, activity level, and psychometric parameters. Conclusion Bilateral shoulder arthroplasties performed with different prosthesis types in each shoulder resulted in good functional outcomes and high patient satisfaction rates. Although the objective results in terms of ROM were better following anatomic total shoulder arthroplasty, no difference was observed in final Constant score or subjective shoulder value. However, some specific tasks, such as sports and lifting 10 pounds above shoulder level, are more easily performed after anatomic total shoulder arthroplasty compared with reverse shoulder arthroplasty. References 1. Gartsman GM, Edwards TB. Shoulder Arthoplasty. Philadelphia, PA; Saunders; Sperling JW, Cofield RH, Rowland CM. 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