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The Bone & Joint Journal
Vol. 105-B, Issue 9 | Pages 1000 - 1006
1 Sep 2023
Macken AA Haagmans-Suman A Spekenbrink-Spooren A van Noort A van den Bekerom MPJ Eygendaal D Buijze GA

Aims. The current evidence comparing the two most common approaches for reverse total shoulder arthroplasty (rTSA), the deltopectoral and anterosuperior approach, is limited. This study aims to compare the rate of loosening, instability, and implant survival between the two approaches for rTSA using data from the Dutch National Arthroplasty Registry with a minimum follow-up of five years. Methods. All patients in the registry who underwent a primary rTSA between January 2014 and December 2016 using an anterosuperior or deltopectoral approach were included, with a minimum follow-up of five years. Cox and logistic regression models were used to assess the association between the approach and the implant survival, instability, and glenoid loosening, independent of confounders. Results. In total, 3,902 rTSAs were included. A deltopectoral approach was used in 54% (2,099/3,902) and an anterosuperior approach in 46% (1,803/3,902). Overall, the mean age in the cohort was 75 years (50 to 96) and the most common indication for rTSA was cuff tear arthropathy (35%; n = 1,375), followed by osteoarthritis (29%; n = 1,126), acute fracture (13%; n = 517), post-traumatic sequelae (10%; n = 398), and an irreparable cuff rupture (5%; n = 199). The two high-volume centres performed the anterosuperior approach more often compared to the medium- and low-volume centres (p < 0.001). Of the 3,902 rTSAs, 187 were revised (5%), resulting in a five-year survival of 95.4% (95% confidence interval 94.7 to 96.0; 3,137 at risk). The most common reason for revision was a periprosthetic joint infection (35%; n = 65), followed by instability (25%; n = 46) and loosening (25%; n = 46). After correcting for relevant confounders, the revision rate for glenoid loosening, instability, and the overall implant survival did not differ significantly between the two approaches (p = 0.494, p = 0.826, and p = 0.101, respectively). Conclusion. The surgical approach used for rTSA did not influence the overall implant survival or the revision rate for instability or glenoid loosening. Cite this article: Bone Joint J 2023;105-B(9):1000–1006


The Bone & Joint Journal
Vol. 104-B, Issue 3 | Pages 401 - 407
1 Mar 2022
Kriechling P Zaleski M Loucas R Loucas M Fleischmann M Wieser K

Aims. The aim of this study was to report the incidence of implant-related complications, further operations, and their influence on the outcome in a series of patients who underwent primary reverse total shoulder arthroplasty (RTSA). Methods. The prospectively collected clinical and radiological data of 797 patients who underwent 854 primary RTSAs between January 2005 and August 2018 were analyzed. The hypothesis was that the presence of complications would adversely affect the outcome. Further procedures were defined as all necessary operations, including reoperations without change of components, and partial or total revisions. The clinical outcome was evaluated using the absolute and relative Constant Scores (aCS, rCS), the Subjective Shoulder Value (SSV) scores, range of motion, and pain. Results. The overall surgical site complication rate was 22% (188 complications) in 152 patients (156 RTSAs; 18%) at a mean follow-up of 46 months (0 to 169). The most common complications were acromial fracture (in 44 patients, 45 RTSAs; 5.3%), glenoid loosening (in 37 patients, 37 RTSAs; 4.3%), instability (in 23 patients, 23 RTSAs; 2.7%), humeral fracture or loosening of the humeral component (in 21 patients, 21 RTSAs; 2.5%), and periprosthetic infection (in 14 patients, 14 RTSAs; 1.6%). Further surgery was undertaken in 79 patients (82 RTSAs) requiring a total of 135 procedures (41% revision rate). The most common indications for further surgery were glenoid-related complications (in 23 patients, 23 RTSAs; 2.7%), instability (in 15 patients, 15 RTSAs; 1.8%), acromial fractures (in 11 patients, 11 RTSAs; 1.3%), pain and severe scarring (in 13 patients, 13 RTSAs; 1.5%), and infection (in 8 patients, 8 RTSAs; 0.9%). Patients who had a complication had significantly worse mean rCS scores (57% (SD 24%) vs 81% (SD 16%)) and SSV scores (53% (SD 27%) vs 80% (SD 20%)) compared with those without a complication. If revision surgery was necessary, the outcome was even further compromised (mean rCS score: 51% (SD 23%) vs 63% (SD 23%); SSV score: 4% (SD 25%) vs 61% (SD 27%). Conclusion. Although the indications for, and use of, a RTSA are increasing, it remains a demanding surgical procedure. We found that about one in five patients had a complication and one in ten required further surgery. Both adversely affected the outcome. Cite this article: Bone Joint J 2022;104-B(3):401–407


The Bone & Joint Journal
Vol. 102-B, Issue 11 | Pages 1438 - 1445
1 Nov 2020
Jang YH Lee JH Kim SH

Aims. Scapular notching is thought to have an adverse effect on the outcome of reverse total shoulder arthroplasty (RTSA). However, the matter is still controversial. The aim of this study was to determine the clinical impact of scapular notching on outcomes after RTSA. Methods. Three electronic databases (PubMed, Cochrane Database, and EMBASE) were searched for studies which evaluated the influence of scapular notching on clinical outcome after RTSA. The quality of each study was assessed. Functional outcome scores (the Constant-Murley scores (CMS), and the American Shoulder and Elbow Surgeons (ASES) scores), and postoperative range of movement (forward flexion (FF), abduction, and external rotation (ER)) were extracted and subjected to meta-analysis. Effect sizes were expressed as weighted mean differences (WMD). Results. In all, 11 studies (two level III and nine level IV) were included in the meta-analysis. All analyzed variables indicated that scapular notching has a negative effect on the outcome of RTSA . Statistical significance was found for the CMS (WMD –3.11; 95% confidence interval (CI) –4.98 to –1.23), the ASES score (WMD –6.50; 95% CI –10.80 to –2.19), FF (WMD –6.3°; 95% CI –9.9° to –2.6°), and abduction (WMD –9.4°; 95% CI –17.8° to –1.0°), but not for ER (WMD –0.6°; 95% CI –3.7° to 2.5°). Conclusion. The current literature suggests that patients with scapular notching after RTSA have significantly worse results when evaluated by the CMS, ASES score, and range of movement in flexion and abduction. Cite this article: Bone Joint J 2020;102-B(11):1438–1445


The Bone & Joint Journal
Vol. 105-B, Issue 11 | Pages 1189 - 1195
1 Nov 2023
Kim JS Kim SH Kim SC Park JH Kim HG Lee SM Yoo JC

Aims

The aim of this study was to compare the clinical and radiological outcomes of reverse shoulder arthroplasty (RSA) using small and standard baseplates in Asian patients, and to investigate the impact of a mismatch in the sizes of the glenoid and the baseplate on the outcomes.

Methods

This was retrospective analysis of 50 and 33 RSAs using a standard (33.8 mm, ST group) and a small (29.5 mm, SM group) baseplate of the Equinoxe reverse shoulder system, which were undertaken between January 2017 and March 2021. Radiological evaluations included the size of the glenoid, the β-angle, the inclination of the glenoid component, inferior overhang, scapular notching, the location of the central cage in the baseplate within the vault and the mismatch in size between the glenoid and baseplate. Clinical evaluations included the range of motion (ROM) and functional scores. In subgroup analysis, comparisons were performed between those in whom the vault of the glenoid was perforated (VP group) and those in whom it was not perforated (VNP group).


The Bone & Joint Journal
Vol. 103-B, Issue 5 | Pages 813 - 821
1 May 2021
Burden EG Batten TJ Smith CD Evans JP

Aims. This systematic review asked which patterns of complications are associated with the three reverse total shoulder arthroplasty (RTSA) prosthetic designs, as classified by Routman et al, in patients undergoing RTSA for the management of cuff tear arthropathy, massive cuff tear, osteoarthritis, and rheumatoid arthritis. The three implant design philosophies investigated were medial glenoid/medial humerus (MGMH), medial glenoid/lateral humerus (MGLH), and lateral glenoid/medial humerus (LGMH). Methods. A systematic review of the literature was performed via a search of MEDLINE and Embase. Two reviewers extracted data on complication occurrence and patient-reported outcome measures (PROMs). Meta-analysis was conducted on the reported proportion of complications, weighted by sample size, and PROMs were pooled using the reported standardized mean difference (SMD). Quality of methodology was assessed using Wylde’s non-summative four-point system. The study was registered with PROSPERO (CRD42020193041). Results. A total of 42 studies met the inclusion and exclusion criteria. Rates of scapular notching were found to be significantly higher in MGMH implants (52% (95% confidence interval (CI) 40 to 63)) compared with MGLH ((18% (95% CI 6 to 34)) and LGMH (12% (95% CI 3 to 26)). Higher rates of glenoid loosening were seen in MGMH implants (6% (95% CI 3 to 10)) than in MGLH implants (0% (95% CI 0 to 2)). However, strength of evidence for this finding was low. No significant differences were identified in any other complication, and there were no significant differences observed in PROMs between implant philosophies. Conclusion. This systematic review has found significant improvement in PROMS and low complication rates across the implant philosophies studied. Scapular notching was the only complication found definitely to have significantly higher prevalence with the MGMH implant design. Cite this article: Bone Joint J 2021;103-B(5):813–821


The Bone & Joint Journal
Vol. 104-B, Issue 12 | Pages 1334 - 1342
1 Dec 2022
Wilcox B Campbell RJ Low A Yeoh T

Aims. Rates of reverse total shoulder arthroplasty (rTSA) continue to grow. Glenoid bone loss and deformity remains a technical challenge to the surgeon and may reduce improvements in patients’ outcomes. However, there is no consensus as to the optimal surgical technique to best reconstruct these patients’ anatomy. This review aims to compare the outcomes of glenoid bone grafting versus augmented glenoid prostheses in the management of glenoid bone loss in primary reverse total shoulder arthroplasty. Methods. This systematic review and meta-analysis evaluated study-level data in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We performed searches of Medline (Ovid), Embase (Ovid), and PubMed from their dates of inception to January 2022. From included studies, we analyzed data for preoperative and postoperative range of motion (ROM), patient-reported functional outcomes, and complication rates. Results. A total of 13 studies (919 shoulders) were included in the analysis. The mean age of patients at initial evaluation was 72.2 years (42 to 87), with a mean follow-up time of 40.7 months (24 to 120). Nine studies with 292 rTSAs evaluated the use of bone graft and five studies with 627 rTSAs evaluated the use of augmented glenoid baseplates. One study was analyzed in both groups. Both techniques demonstrated improvement in patient-reported outcome measures and ROM assessment, with augmented prostheses outperforming bone grafting on improvements in the American Shoulder and Elbow Surgeons Score. There was a higher complication rate (8.9% vs 3.5%; p < 0.001) and revision rate among the bone grafting group compared with the patients who were treated with augmented prostheses (2.4% vs 0.6%; p = 0.022). Conclusion. This review provides strong evidence that both bone graft and augmented glenoid baseplate techniques to address glenoid bone loss give excellent ROM and functional outcomes in primary rTSA. The use of augmented base plates may confer fewer complications and revisions. Cite this article: Bone Joint J 2022;104-B(12):1334–1342


The Bone & Joint Journal
Vol. 105-B, Issue 12 | Pages 1303 - 1313
1 Dec 2023
Trammell AP Hao KA Hones KM Wright JO Wright TW Vasilopoulos T Schoch BS King JJ

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. Cite this article: Bone Joint J 2023;105-B(12):1303–1313


The Bone & Joint Journal
Vol. 103-B, Issue 2 | Pages 360 - 365
1 Feb 2021
Mahendraraj KA Shields MV Grubhofer F Golenbock SW Jawa A

Aims. Existing literature indicates that inferiorly inclined glenoid baseplates following reverse total shoulder arthroplasty (RSA) produce better outcomes compared to superiorly inclined baseplates. We aim to compare clinical outcomes for RSAs with superiorly and neutrally/inferiorly inclined lateralized glenospheres. Methods. We retrospectively reviewed 154 consecutive patients undergoing RSA between July 2015 and July 2017 by one single-fellowship trained surgeon (AJ). Two raters (KAM and MVS) independently measured glenoid inclination in preoperative and minimum two year follow-up radiographs (anteroposterior/Grashey) using the RSA angle. Inclination was then compared to patient-reported outcomes, range of motion (ROM), and independently assessed degree of scapular notching and staging of heterotopic ossification at two year follow-up. Results. Median postoperative inclination for each group was found to be -3.6° (interquartile range (IQR) -2.1 to -6.9) and 6.0° (3.2° to 10.1°) for the neutrally/inferiorly and superiorly inclined cohorts, respectively. Preoperative inclination was highly associated with postoperative inclination (p = 0.004). When comparing superiorly and neutrally/inferiorly inclined glenospheres, there were no differences in heterotopic ossification (p = 0.606), scapular notching (p = 0.367), American Shoulder and Elbow Surgeons score (p = 0.419), Single Assessment Numeric Evaluation (p = 0.417), Visual Analogue Scale (VAS) pain score (p = 0.290), forward elevation (p = 0.161), external rotation (p = 0.537), or internal rotation (p = 0.656). Conclusion. Compared to neutral and inferior inclination, up to 6° ± 3° of superior glenoid baseplate inclination on a lateralized RSA design produces no differences in postoperative ROM or patient-reported outcomes, and produces similar levels of scapular notching and heterotopic ossification. Additionally, the degree of preoperative inclination represents an important factor in surgical decision-making as it is strongly associated with postoperative inclination. It is important to note that the findings of this study are only reflective of lateralized RSA prostheses. Cite this article: Bone Joint J 2021;103-B(2):360–365


Bone & Joint 360
Vol. 12, Issue 1 | Pages 30 - 33
1 Feb 2023

The February 2023 Shoulder & Elbow Roundup. 360. looks at: Arthroscopic capsular release or manipulation under anaesthesia for frozen shoulder?; Distal biceps repair through a single incision?; Distal biceps tendon ruptures: diagnostic strategy through physical examination; Postoperative multimodal opioid-sparing protocol vs standard opioid prescribing after knee or shoulder arthroscopy: a randomized clinical trial; Graft healing is more important than graft technique in massive rotator cuff tear; Subscapularis tenotomy versus peel after anatomic shoulder arthroplasty; Previous rotator cuff repair increases the risk of revision surgery for periprosthetic joint infection after reverse shoulder arthroplasty; Conservative versus operative treatment of acromial and scapular spine fractures following reverse total shoulder arthroplasty


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_16 | Pages 13 - 13
1 Dec 2021
Ramesh K Yusuf M Makaram N Milton R Mathew A Srinivasan M
Full Access

Abstract. Objective. To investigate the safety and cost-effectiveness of interscalene brachial plexus block/regional anaesthesia (ISB-RA) in patients undergoing reverse total shoulder replacement. Methods. This retrospective study included 15 patients with symptomatic rotator cuff arthropathy who underwent reverse total shoulder arthroplasty (rTSA) under ISB-RA without general anaesthesia in the beach chair position from 2010 to 2018. The mean patient age was 77 years (range 59–82 years). Patients had associated medical comorbidities: American Society of Anesthesiologists (ASA) grade 2–4. Assessed parameters were: duration of anaesthesia, intra-operative systolic blood pressure variation, sedation and vasopressor use, duration of post-operative recovery, recovery scores, length of stay, and complications. A robust cost analysis was also performed. Results. The mean (range) duration of anaesthesia was 38.66 (20–60) min. Maximum and minimum intra-operative systolic blood pressure ranges were 130–210 and 75–145 mmHg, respectively (mean [range] drop, 74.13 [33–125] mmHg). Mean (range) propofol dose was 1.74 (1–3.0) mg/kg/h. The Median (interquartile range) post-operative recovery time was 30 (20–50) min. The mean (range) postoperative recovery score (local scale, range 5–28 where lower values are superior) was 5.2 (5–8). The mean (range) length of stay was 8 (1–20 days); the two included patients with ASA grade 2 were both discharged within 24 hours. One patient with predisposing history developed pneumonia; however, there were no complications related to ISB-RA. The mean (range) cost per patient was £101.36 (£59.80-£132.20). Conclusions. Our data demonstrate that rTSA under ISB-RA is safe, cost-effective and a potentially viable alternative for patients with multiple comorbidities. Notably, patients with ASA grade 2 who underwent rTSA under ISB-RA had a reduced length of stay and were discharged within 24 hours


Bone & Joint 360
Vol. 13, Issue 1 | Pages 26 - 29
1 Feb 2024

The February 2024 Shoulder & Elbow Roundup. 360. looks at: Does indomethacin prevent heterotopic ossification following elbow fracture fixation?; Arthroscopic capsular shift in atraumatic shoulder joint instability; Ultrasound-guided lavage with corticosteroid injection versus sham; Combined surgical and exercise-based interventions following primary traumatic anterior shoulder dislocation: a systematic review and meta-analysis; Are vascularized fibula autografts a long-lasting reconstruction after intercalary resection of the humerus for primary bone tumours?; Anatomical versus reverse total shoulder arthroplasty with limited forward elevation; Tension band or plate fixation for simple displaced olecranon fractures?; Is long-term follow-up and monitoring in shoulder and elbow arthroplasty needed?


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_4 | Pages 113 - 113
1 Apr 2019
Verstraete M Conditt M Wright T Zuckerman J Youderian A Parsons I Jones R Decerce J Goodchild G Greene A Roche C
Full Access

Introduction & Aims. Over the last decade, sensor technology has proven its benefits in total knee arthroplasty, allowing the quantitative assessment of tension in the medial and lateral compartment of the tibiofemoral joint through the range of motion (VERASENSE, OrthoSensor Inc, FL, USA). In reversal total shoulder arthroplasty, it is well understood that stability is primarily controlled by the active and passive structures surrounding the articulating surfaces. At current, assessing the tension in these stabilizing structures remains however highly subjective and relies on the surgeons’ feel and experience. In an attempt to quantify this feel and address instability as a dominant cause for revision surgery, this paper introduces an intra-articular load sensor for reverse total shoulder arthroplasty (RTSA). Method. Using the capacitive load sensing technology embedded in instrumented tibial trays, a wireless, instrumented humeral trial has been developed. The wireless communication enables real-time display of the three-dimensional load vector and load magnitude in the glenohumeral joint during component trialing in RTSA. In an in-vitro setting, this sensor was used in two reverse total shoulder arthroplasties. The resulting load vectors were captured through the range of motion while the joint was artificially tightened by adding shims to the humeral tray. Results. For both shoulder specimens, the newly developed sensor provided insight in the load magnitude and characteristics through the range of motion. In neutral rotation and under a condition assessed as neither too tight nor too loose, glenohumeral loads in the range of 10–30lbs were observed. As expected, with increasing shim thickness these intra- articular load magnitudes increased. Assessing the load variations through the range of motion, high peak forces of up to 120 lbs were observed near the limits of the range of motion, most pronounced during external humeral rotation. Conclusions. In conclusion, this paper presents an intra-articular load sensor that can be used during the trialing phase in reverse total shoulder arthroplasty. A first series of cadaveric experiments provided evidence of realistic load ranges and load characteristics with respect to the end of the range of motion. Currently, effort is undertaken to develop a biomechanically validated load range that can serve as a target in surgery


The Bone & Joint Journal
Vol. 103-B, Issue 8 | Pages 1333 - 1338
2 Aug 2021
Kankanalu P Borton ZM Morgan ML Cresswell T Espag MP Tambe AA Clark DI

Aims. Reverse total shoulder arthroplasty (RTSA) using trabecular metal (TM)-backed glenoid implants has been introduced with the aim to increase implant survival. Only short-term reports on the outcomes of TM-RTSA have been published to date. We aim to present the seven-year survival of TM-backed glenoid implants along with minimum five-year clinical and radiological outcomes. Methods. All consecutive elective RTSAs performed at a single centre between November 2008 and October 2014 were reviewed. Patients who had primary TM-RTSA for rotator cuff arthropathy and osteoarthritis with deficient cuff were included. A total of 190 shoulders in 168 patients (41 male, 127 female) were identified for inclusion at a mean of 7.27 years (SD 1.4) from surgery. The primary outcome was survival of the implant with all-cause revision and aseptic glenoid loosening as endpoints. Secondary outcomes were clinical, radiological, and patient-related outcomes with a five-year minimum follow-up. Results. The implant was revised in ten shoulders (5.2%) with a median time to revision of 21.2 months (interquartile range (IQR) 9.9 to 41.8). The Kaplan-Meier survivorship estimate at seven years was 95.9% (95% confidence interval (CI) 91.7 to 98; 35 RTSAs at risk) for aseptic mechanical failure of the glenoid and 94.8% (95% CI 77.5 to 96.3; 35 RTSAs at risk) for all-cause revision. Minimum five-year clinical and radiological outcomes were available for 103 and 98 RTSAs respectively with a median follow-up time of six years (IQR 5.2 to 7.0). Median postoperative Oxford Shoulder Score was 38 (IQR 31 to 45); median Constant and Murley score was 60 (IQR 47.5 to 70); median forward flexion 115° (IQR 100° to 125°); median abduction 95° (IQR 80° to 120°); and external rotation 25° (IQR 15° to 40°) Scapular notching was seen in 62 RTSAs (63.2%). Conclusion. We present the largest and longest-term series of TM-backed glenoid implants demonstrating 94.8% all-cause survivorship at seven years. Specifically pertaining to glenoid loosening, survival of the implant increased to 95.9%. In addition, we report satisfactory minimum five-year clinical and radiological outcomes. Cite this article: Bone Joint J 2021;103-B(8):1333–1338


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 11 - 11
1 Jan 2016
Song IS Shin SY
Full Access

Purpose. To evaluate the results of reverse total shoulder arthroplasty for complicated proximal humerus fractures in old ages. Materials and Methods. We retrospectively evaluated 13 cases who underwent reverse total shoulder arthroplasty for proximal humerus fracture, fracture-dislocation and nonunions of the fractures. Mean age was 77(68–87)years old and mean follow-up period was 15.2(12–26)months. four part fractures of proximal humerus in 7 cases, fracture-dislocation in 3 cases, locked dislocation with greater tuberosity in 2 cases, nonunion with defiency of rotator cuff in 1 case were included. We evaluated mean ASES, mean UCLA, mean KSS, mean SST and mean range of motion(ROM). Results. Postoperative mean ASES was 59(13–98.5), mean UCLA was 21(12–34), mean KSS was 62(21–94), mean SST was 5(1–11). Postoperative mean ROM was 103°(30°–135°) in forward flexion, 93°(30°–135°) in abduction, 21°(0°–45°) in external rotation and L4 level in internal rotation. The complications were not shown in any cases except for resolved heterotropic ossification. 4 cases demonstrated bony unions on greater tuberosity and 4 cases showed scapular notching on last follow-up. Conclusions. Reverse total shoulder arthroplasty for complicated proximal humerus fracture, nonunion of the fracture, or chronic locked dislocation seems to be a good treatment options. Regardless of bony union of the greater tuberosity, reverse total shoulder arthroplasty for the complicated proximal humerus fractures had a satisfied results


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 537 - 537
1 Dec 2013
Song IS
Full Access

Purpose:. To evaluate the results of reverse total shoulder arthroplasty for complicated proximal humerus fractures in old ages. Materials and Methods:. We retrospectively evaluated 13 cases who underwent reverse total shoulder arthroplasty for proximal humerus fracture, fracture-dislocation and nonunions of the fractures. Mean age was 77 years old and mean follow-up period was 15.2(12–26) months. four part fractures of proximal humerus in 7 cases, fracture-dislocation in 3 cases, locked dislocation with greater tuberosity in 2 cases, nonunion with defiency of rotator cuff in 1 case were included (Fig. 1, Fig. 2, Fig. 3). We evaluated mean ASES, mean UCLA, mean KSS, mean SST and mean range of motion (ROM). Results:. Postoperative mean ASES was 59(13–98.5), mean UCLA was 21(12–34), mean KSS was 62(21–94), mean SST was 5(1–11). Postoperative mean ROM was 103° in forward flexion, 93° in abduction, 21° in external rotation and L4 level in internal rotation. 4 cases demonstrated bony unions on greater tuberosity and 4 cases showed scapular notching on last follow-up. Conclusion:. Reverse total shoulder arthroplasty for complicated proximal humerus fracture, nonunion of the fracture, or chronic locked dislocation seems to be a good treatment options. Regardless of bony union of the greater tuberosity, reverse total shoulder arthroplasty for the complicated proximal humerus fractures had a satisfied results. Key words: Shoulder, Proximal humerus fracture, Reverse total shoulder arthroplasty


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 40 - 40
23 Feb 2023
Critchley O Guest C Warby S Hoy G Page R
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Glenoid bone grafting in reverse total shoulder arthroplasty (RTSA) has emerged as an effective method of restoring bone stock in the presence of complex glenoid bone loss, yet there is limited published evidence on efficacy. The aim of this study was to conduct an analysis of clinical and radiographic outcomes associated with glenoid bone grafting in primary RTSA. Patients who underwent a primary RTSA with glenoid bone grafting were retrospectively identified from the databases of two senior shoulder surgeons. Inclusion criteria included minimum of 12 months clinical and/or radiographical follow up. Patients underwent preoperative clinical and radiographic assessment. Graft characteristics (source, type, preparation), range of movement (ROM), patient-reported outcome measures (Oxford Shoulder Scores [OSS]), and complications were recorded. Radiographic imaging was used to analyse implant stability, graft incorporation, and notching by two independent reviewers. Between 2013 and 2021, a total of 53 primary RTSA procedures (48 patients) with glenoid bone grafting were identified. Humeral head autograft was used in 51 (96%) of cases. Femoral head allograft was utilised in two cases. Depending on the morphology of glenoid bone loss, a combination of structural (corticocancellous) and non-structural (cancellous) grafts were used to restore glenoid bone stock and the joint line. All grafts were incorporated at review. The mean post-operative OSS was significantly higher than the pre-operative OSS (40 vs. 22, p < 0.001). ROM was significantly improved post-operatively. One patient is being investigated for residual activity-related shoulder pain. This patient also experienced scapular notching resulting in the fracturing of the inferior screw. One patient experienced recurrent dislocations but was not revised. Overall, at short term follow up, glenoid bone grafting was effective in addressing glenoid bone loss with excellent functional and clinical outcomes when used for complex bone loss in primary RTSA. The graft incorporation rate was high, with an associated low complication rate


The Bone & Joint Journal
Vol. 96-B, Issue 9 | Pages 1239 - 1243
1 Sep 2014
Zafra M Uceda P Flores M Carpintero P

Patients with pain and loss of shoulder function due to nonunion of a fracture of the proximal third of the humerus may benefit from reverse total shoulder replacement. This paper reports a prospective, multicentre study, involving three hospitals and three surgeons, of 35 patients (28 women, seven men) with a mean age of 69 years (46 to 83) who underwent a reverse total shoulder replacement for the treatment of nonunion of a fracture of the proximal humerus. Using Checchia’s classification, nine nonunions were type I, eight as type II, 12 as type III and six as type IV. The mean follow-up was 51 months (24 to 99). Post-operatively, the patients had a significant decrease in pain (p < 0.001), and a significant improvement in flexion, abduction, external rotation and Constant score (p < 0.001), but not in internal rotation. A total of nine complications were recorded in seven patients: six dislocations, one glenoid loosening in a patient who had previously suffered dislocation, one transitory paresis of the axillary nerve and one infection. Reverse total shoulder replacement may lead to a significant reduction in pain, improvement in function and a high degree of satisfaction. However, the rate of complications, particularly dislocation, was high. Cite this article: Bone Joint J 2014;96-B:1239–43


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 83 - 83
23 Feb 2023
Rossignol SL Boekel P Grant A Doma K Morse L
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Currently, the consensus regarding subscapularis tendon repair during a reverse total shoulder arthroplasty (rTSA) is to do so if it is possible. Repair is thought to decrease the risk of dislocation and improve internal rotation but may also increase stiffness and improvement in internal rotation may be of subclinical benefit. Aim is to retrospectively evaluate the outcomes of rTSA, with or without a subscapularis tendon repair. We completed a retrospective review of 51 participants (25 without and 26 with subscapularis repair) who received rTSR by a single-surgeon using a single-implant. Three patient reported outcome measures (PROM) were assessed pre-operatively and post-operative at twelve months, as well as range of movement (ROM) and plain radiographs. Statistical analysis utilized unpaired t tests for parametric variables and Mann-Whitney U test for nonparametric variables. External Rotation ROM pre-operatively was the only variable with a significance difference (p=0.02) with the subscapularis tendon repaired group having a greater range. Pre- and post-operative abduction (p=0.72 & 0.58), forward flexion (p=0.67 & 0.34), ASES (p=0.0.06 & 0.78), Oxford (p=0.0.27 & 0.73) and post-operative external rotation (p=0.17). Greater external rotation ROM pre-operatively may be indicative of the ability to repair the subscapularis tendon intra-operatively. However, repair does not seem to improve clinical outcome at 12 months. There was no difference of the PROMs and AROMs between the subscapularis repaired and not repaired groups for any of the variables at the pre-operative or 12 month post operative with the exception of the external rotation ROM pre-operatively. We can conclude that from PROM or AROM perspective there is no difference if the tendon is repaired or not in a rTSR and indeed the patients without the repair may have improved outcomes at 12 months


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_19 | Pages 17 - 17
1 Apr 2013
Iqbal HJ Williams G Redfern TR
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Introduction. Reverse total shoulder replacement is performed for the treatment of rotator cuff arthropathy, massive irreparable cuff tears and failed shoulder hemiarthroplasty with irreparable rotator cuff tears. The aim of this study was to assess the clinical and radiological outcome of single surgeon series of Equinoxe® reverse total shoulder replacement at a district general hospital. Materials/Methods. Consecutive patients who underwent Equinoxe® reverse total shoulder replacement at our unit from Jun 2008 to Dec 2010 were retrospectively reviewed. Indications for surgery, complications and radiological outcomes were assessed. Oxford shoulder score was used to assess the functional outcome. Results. Between Jun 2008 and Dec 2012, forty-one reverse total shoulder replacements were performed by the senior author in 37 patients. Of these, Equinoxe® prostheses were used in 27 operations (26 patients). These included 22 female and 4 male patients. Cuff arthropathy was the commonest preoperative diagnosis (23 patients), followed by proximal humeral fracture non-union (2 patients), failed hemiarthroplasty (one patient) and failed resurfacing (one patient). The mean follow up was 10 months (3 to 17 months). At the time of the study, three patients had died due to unrelated causes, two were not contactable and the remaining 21 patients were analysed. The mean oxford shoulder score was 35.8 (21–48). Nineteen patients (90.5%) graded their outcome a good to excellent while 2 patients (9.5%) graded as poor. Seventeen patients (81%) expressed that they would recommend this operation. One patient (4.7%) had infection and another had dislocation. Overall, there were 3 reoperations (14.3%); first washout, second change of humeral tray and third excision of lateral end of clavicle and reattachment of deltoid. Two patients (9.5%) had small glenoid notching. There was no loosening, neurovascular injury or postoperative haematoma. Conclusion. Early outcome of Equinoxe reverse shoulder replacement is promising. Longer follow-up is required to further assess the outcome


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_16 | Pages 71 - 71
1 Dec 2021
Giles W Komperla S Flatt E Gandhi M Eyre-Brook A Jones V Papanna M Eves T Thyagarajan D
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Abstract. Background/Objectives. The incidence of reverse total shoulder replacement (rTSR) implantation is increasing globally, but apprehension exists regarding complications and associated challenges. We retrospectively analysed the senior author's series of rTSR from a tertiary centre using the VAIOS shoulder system, a modular 4th generation implant. We hypothesised that the revision rTSR cohort would have less favourable outcomes and more complications. Methods. 114 patients underwent rTSR with the VAIOS system, over 7 years. The primary outcome was implant survival. Secondary outcomes were Oxford shoulder scores (OSS), radiographic analysis (scapular notching, tuberosity osteolysis, and periprosthetic radiolucent lines) and complications. Results. There were 55 Primary rTSR, 31 Revision rTSR and 28 Trauma rTSR. Implant survival: Primary rTSR- 0 revisions, average 3.35-year follow-up. Revision rTSR-1 revision (4.17%), average 3.52-year follow-up. Trauma rTSR- 1 revision (3.57%), average 4.56-year follow-up OSS: Average OSS improved from 15.39 to 33.8 (Primary rTSR) and from 15.11 to 29.1 (Revision rTSR). Average post-operative OSS for the Trauma rTSR was 31.4 Radiological analysis and complications: Low incidence of scapular notching One hairline fracture below the tip of stem, noted incidentally, which required no treatment. One periprosthetic fracture after alcohol related fall. Treated non-surgically One joint infection requiring two-stage revision to rTSR. One dislocation noted at 2 year follow up. This patient had undergone nerve grafting within 6 months of rTSR for axillary nerve injury sustained during the original fracture dislocation. One acromial fracture with tibial and distal humeral fracture after a fall. Conclusions. The 4th generation modular VAIOS implant is a reliable option for various indications. The revision rTSR cohort had favourable outcomes with low complication rates. In this series, early-to-medium term results suggest lower revision rates and good functional outcomes when compared to published reports. We plan to monitor long-term implant survivorship and patient reported outcomes. Declaration of Interest. (a) fully declare any financial or other potential conflict of interest


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_1 | Pages 22 - 22
1 Feb 2020
Van De Kleut M Athwal G Yuan X Teeter M
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Introduction. Reverse total shoulder arthroplasty (RTSA) is rapidly being adopted as the standard procedure for a growing number of shoulder arthropathies. Though short-term outcomes are promising, mid- and long-term follow-ups present a number of complications – among them, humeral stem and glenosphere component loosening. Though not the primary complication, previously reported aseptic loosening required revision in 100% of cases. As the number of patients undergoing RTSA increases, especially in the younger population, it is important for surgeons to identify and utilize prostheses with stable long-term fixation. It has previously been shown in the hip and knee literature that implant migration in the first two years following surgery is predictive of later failure due to loosening in the 5=10-year postoperative window. The purpose of this study is to, for the first time, evaluate the pattern and total magnitude of implant migration in reverse shoulder arthroplasty using the gold standard imaging technique radiostereometric analysis (RSA). Methods. Forty patients were prospectively randomized to receive either a cemented or press-fit humeral stem, and a glenosphere secured to the glenoid with either autologous bone graft or 3D printed porous titanium for primary reverse total shoulder arthroplasty. Following surgery, participants are imaged using RSA, a calibrated, stereo x-ray technique. Radiographs are acquired at 6 weeks (baseline), 3 months, 6 months, 1 year, and 2 years. Migration of the humeral stem and glenosphere at each time point is compared to baseline. Migration of the prostheses is independently compared between humeral stem fixation groups and glenosphere fixation groups using a two-way repeated measures ANOVA with Tukey's test for multiple comparisons. Results. Follow-ups are ongoing and preliminary results are presented. Significant differences were observed at the 6-month and 1-year time points for superior-inferior translation (p = 0.0067, p = 0.0048), and total three-dimensional translation (p = 0.0011, p = 0.0272) between humeral stems, with press-fit humeral stems subsiding significantly more than cemented stems. Migration between the 6-month and 1-year time points was minimal for both stem fixation groups (less than 0.2 mm). No significant differences were observed along any axis at any time point for the glenosphere fixation groups. Conclusion. There is a trend towards increased subsidence with the use of press-fit stems compared to cemented stems in the first six months postoperatively, as is expected. Both implant fixation techniques demonstrate stability from six months through one year, and this trend is expected through two-year follow-up. Similarly, both glenosphere fixation techniques demonstrate immediate and stable fixation through one year


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_IV | Pages 570 - 570
1 Oct 2010
Beekman P Berghs B De Wilde L Karelse A Katusic D
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Aims of the study: To assess the results of one-stage revision of infected reverse total shoulder arthroplasty as a new treatment for this major surgical complication. Materials: 11 consecutive patients with infected reverse shoulder prosthesis (DePuy International Ltd, Leeds, UK) were treated with a direct-exchange reverse total shoulder arthroplasty between March 2005 and June 2007. These patients were retrospectively followed. Methods: Via a superior extended deltoideopectoral, clavicular osteotomy approach, according to Redfern-Wallace, a removal of the prosthesis is performed. Multiple operative specimens (4 to 8) are taken and cultured. A thorough synovectomy is performed before implanting a new reverse total shoulder arthroplasty (7 Delta. ®. 3.2 tsp and 4 DeltaXtend. ®. tsp). A gentamycine (Duracol. ®. ) impregnated membrane is interpositioned between baseplate and glenosphere. Immediate postoperative passive and active mobilisation is permitted if no pain is present. Results: Clinical symptoms are seldom severe pain (3) or severe limitation of function (3). A fistula is mainly present (8) without alterating the function. No prosthetic loosening was present at the humeral and glenoid site confirming the absence of radiological infectious signs. All but one patient are considered free of infection at mean follow up of 24 months (12m – 36m) and without antibiotic treatment for minimum 6 months. In only 1 patient the infection persisted necessitating a two-stage revision, unfortunately without definitive cure. Only three early complications are seen (< 2 months: posterior dislocation, postoperative haematoma and clavicle fracture). The mean postoperative Constant-Murley score was 52 (14–81) at latest follow up. Peroperative samples identified Propionbacterium species (5), Coagulase-negative staphylococci (4), MRSA (1) and with E.Coli (1) infection. Monobacterial infection was seen in 6 shoulders, multibacterial in 2 shoulders and in 2 shoulders cultures were negative. Discussion: This cohort of patients has a different syndrome than the known infected anatomical prosthesis. This pathology seems to be rarely associated with severe pain (3) or limitation of function (3). Draining fistulas without alterating the function of the shoulder [CS: mean 43 (3–63)] are more frequently present making a preoperative diagnosis easier and more certain. Recurrence rate of infection is comparable to the classical two-stage revision. Preoperative stiff and painful shoulders seems to have a bad prognosis despite definite cure of the infection. Supple shoulders (mainly associated with a fistula) can be treated with a good functional result. Conclusion: One-stage revision arthroplasty is an attractive alternative treatment for infected reverse total shoulder arthroplasty


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 84 - 84
23 Feb 2023
Rossingol SL Boekel P Grant A Doma K Morse L
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The reverse total shoulder replacement (rTSR) has excellent clinical outcomes and prosthesis longevity, and thus, the indications have expanded to a younger age group. The use of a stemless humeral implant has been established in the anatomic TSR; and it is postulated to be safe to use in rTSR, whilst saving humeral bone stock for younger patients. The Lima stemless rTSR is a relatively new implant, with only one paper published on its outcomes. This is a single-surgeon retrospective matched case control study to assess short term outcomes of primary stemless Lima SMR rTSR with 3D planning and Image Derived Instrumentation (IDI), in comparison to a matched case group with a primary stemmed Lima SMR rTSR with 3D planning and IDI. Outcomes assessed: ROM, satisfaction score, PROMs, pain scores; and plain radiographs for loosening, loss of position, notching. Complications will be collated. Patients with at least 1 year of follow-up will be assessed. With comparing the early radiographic and clinical outcomes of the stemless rTSR to a similar patient the standard rTSR, we can assess emerging trends or complications of this new device. 41 pairs of stemless and standard rTSRs have been matched, with 1- and 2-year follow up data. Data is currently being collated. Our hypothesis is that there is no clinical or radiographical difference between the Lima stemless rTSR and the traditional Lima stemmed rTSR


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_4 | Pages 14 - 14
1 Apr 2019
Van De Kleut M Athwal G Yuan X Teeter M
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Introduction. Total shoulder arthroplasty is the fastest growing joint replacement in recent years, with projected compound annual growth rates of 10% for 2016 through 2021 – higher than those of both the hip and knee combined. Reverse total shoulder arthroplasty (RTSA) has gained particular interest as a solution for patients with irreparable massive rotator cuff tears and failed conventional shoulder replacement, for whom no satisfactory intervention previously existed. As the number of indications for RTSA continues to grow, so do implant designs, configurations, and fixation techniques. It has previously been shown that continuous implant migration within the first two years postoperatively is predictive of later loosening and failure in the hip and knee, with aseptic loosening of implant components a guaranteed cause for revision in the reverse shoulder. By identifying implants with a tendency to migrate, they can be eliminated from clinical practice prior to widespread use. The purpose of this study is to, for the first time, evaluate the pattern and magnitude of implant component migration in RTSA using the gold standard imaging technique radiostereometric analysis (RSA). Methods. Forty patients were prospectively randomized to receive either a cemented or press-fit humeral stem, and a glenosphere secured to the glenoid with either autologous bone graft or 3D printed porous titanium (Aequalis Ascend Flex, Wright Medical Group, Memphis, TN, USA) for primary reverse total shoulder arthroplasty. Following surgery, partients are imaged using RSA, a calibrated, stereo x-ray technique, at 6 weeks (baseline), 3 months, 6 months, 1 year, and 2 years. Migration of the humeral stem and glenosphere at each time point is compared to baseline. Preliminary results are presented, with 15 patients having reached the 6-month time point by presentation. Results. Implant migration of ten participants at the 3-month time point is presented. Maximum total point motion (MTPM) is a measure of translation and rotation of the point on the implant that has moved the most from baseline. Average MTPM ± SD of the humeral stem is 1.18 ± 0.65 mm and 0.98 ± 0.46 mm for press-fit (n = 6) and cemented (n = 4) stems, respectively; and 0.25 ± 0.09 mm and 0.47 ± 0.24 mm for bone graft (n = 4) and porous titanium (n = 6) glenosphere fixations, respectively, at the 3-month time point. Conclusion. There is a trend towards increased migration with the use of press-fit humeral stems and porous titanium glenosphere fixation, though no conclusions can be made from the current sample size. Further, though differences in migration magnitude may be observed at early postoperative time points, it is expected that all fixation techniques will show stability from 1 to 2 years postoperatively


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 113 - 113
1 May 2016
Walker D Kinney A Wright T Banks S
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Modern musculoskeletal modeling techniques have been used to simulate shoulders with reverse total shoulder arthroplasty and study how geometric changes resulting from implant placement affect shoulder muscle moment arms. These studies do not, however, take into account how changes in muscle length will affect the force generating capacity of muscles in their post-operative state. The goal of this study was to develop and calibrate a patient-specific shoulder model for subjects with RTSA in order to predict muscle activation during dynamic activities. Patient-specific muscle parameters were estimated using a nested optimization scheme calibrating the model to isometric arm abduction data at 0°, 45° and 90°. The model was validated by comparing predicted muscle activation for dynamic abduction to experimental electromyography recordings. A twelve-degree of freedom model was used with experimental measurements to create a set of patient-specific data (three-dimensional kinematics, muscle activations, muscle moment arms, joint moments, muscle lengths, muscle velocities, tendon slack lengths, optimal fiber lengths and peak isometric forces) estimating muscle parameters corresponding to each patient's measured strength. The optimization varied muscle parameters to minimize the difference between measured and estimated joint moments and muscle activations for isometric abduction trials. This optimization yields a set of patient-specific muscle parameters corresponding to the subject's own muscle strength that can be used to predict muscle activation and muscle lengths for a range of dynamic activities. The model calibration/optimization procedure was performed on arm abduction data for a subject with reverse total shoulder arthroplasty. Muscle activation predicted by the model ranged between 3% and 90% of maximum. The maximum joint moment produced was 20 Nm. The model replicated measured joint moments accurately (R2 > 0.99). The optimized muscle parameter set produced feasible muscle moments and muscle activations for dynamic arm abduction, when calibrated using data from isometric force trials. Current modeling techniques for the upper extremity focus primarily on geometric changes and their effects on shoulder muscle moment arms. In an effort to create patient-specific models, we have developed a framework to predict subject-specific muscle parameters. These estimated muscle parameters, in combination with patient-specific models that incorporate the patient's joint configurations, kinematics and bone anatomy, provide a framework to predict dynamic muscle activation in novel tasks and, for example, predict how joint center changes with reverse total shoulder arthroplasty may affect muscle function


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_3 | Pages 82 - 82
23 Feb 2023
Rossignol SL Boekel P Rikard-Bell M Grant A Brandon B Doma K O'Callaghan W Wilkinson M Morse L
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Glenoid baseplate positioning for reverse total shoulder replacements (rTSR) is key for stability and longevity. 3D planning and image-derived instrumentation (IDI) are techniques for improving implant placement accuracy. This is a single-blinded randomised controlled trial comparing 3D planning with IDI jigs versus 3D planning with conventional instrumentation. Eligible patients were enrolled and had 3D pre-operative planning. They were randomised to either IDI or conventional instrumentation; then underwent their rTSR. 6 weeks post operatively, a CT scan was performed and blinded assessors measured the accuracy of glenoid baseplate position relative to the pre-operative plan. 47 patients were included: 24 with IDI and 23 with conventional instrumentation. The IDI group were more likely to have a guidewire placement within 2mm of the preoperative plan in the superior/inferior plane when compared to the conventional group (p=0.01). The IDI group had a smaller degree of error when the native glenoid retroversion was >10° (p=0.047) when compared to the conventional group. All other parameters (inclination, anterior/posterior plane, glenoids with retroversion <10°) showed no significant difference between the two groups. Both IDI and conventional methods for rTSA placement are very accurate. However, IDI is more accurate for complex glenoid morphology and placement in the superior-inferior plane. Clinically, these two parameters are important and may prevent long term complications of scapular notching or glenoid baseplate loosening. Image-derived instrumentation (IDI) is significantly more accurate in glenoid component placement in the superior/inferior plane compared to conventional instrumentation when using 3D pre-operative planning. Additionally, in complex glenoid morphologies where the native retroversion is >10°, IDI has improved accuracy in glenoid placement compared to conventional instrumentation. IDI is an accurate method for glenoid guidewire and component placement in rTSA


Reverse Total shoulder arthroplasty (RTSA) was initially introduced to treat rotator cuff arthropathy. With proven successful long-term outcomes, it has gained a noteworthy surge in popularity with its indications consequently being extended to treating various traumatic glenohumeral diseases. Several countries holding national registries remain a guide to the use the prosthesis, however a notable lack of epidemiological data still exists. More so in South Africa where the spectrum of joint disease related to communicable diseases such as HIV and tuberculosis may influence indications and patient demographics. By analysing the epidemiology of patients who underwent RTSA at our institution, we aimed to outline the local disease spectrum, the patients afflicted and indications for surgery. A retrospective review of all patients operated within the sports unit between 1 January 2019 and 31 December 2022 was conducted. An analysis of the epidemiological data pertaining to patient demographics, diagnosis, indications for surgery and complications were recorded. Included in the review were 58 patients who underwent primary RTSA over the 4-year period. There were 41 females and 17 male patients, age <55 years (n= 14) >55 years (n=44). The indications included 23 rotator cuff arthropathy (40%), 12 primary glenohumeral osteoarthritis (OA) (20%), 10 avascular necrosis (AVN) humeral head (17%), 7 inflammatory OA (12%), 4 chronic shoulder dislocation (7%) and 2 sequalae of proximal humerus fractures (4%). The study revealed RTSA being performed in patients older than 55 years of age, the main pathologies included rotator cuff arthropathy and primary OA, however AVN and shoulder dislocations secondary to trauma contributed significantly to the total tally of surgeries undertaken. This highlights the disease burden of developing countries contributing to patients presenting for RTSA


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 12 | Pages 1666 - 1669
1 Dec 2012
Gulotta LV Choi D Marinello P Wright T Cordasco FA Craig EV Warren RF

Reverse total shoulder replacement (RTSR) depends on adequate deltoid function for a successful outcome. However, the anterior deltoid and/or axillary nerve may be damaged due to prior procedures or injury. The purpose of this study was to determine the compensatory muscle forces required for scapular plane elevation following RTSR when the anterior deltoid is deficient. The soft tissues were removed from six cadaver shoulders, except for tendon attachments. After implantation of the RTSR, the shoulders were mounted on a custom-made shoulder simulator to determine the mean force in each muscle required to achieve 30° and 60° of scapular plane elevation. Two conditions were tested: 1) Control with an absent supraspinatus and infraspinatus; and 2) Control with anterior deltoid deficiency. Anterior deltoid deficiency resulted in a mean increase of 195% in subscapularis force at 30° when compared with the control (p = 0.02). At 60°, the subscapularis force increased a mean of 82% (p < 0.001) and the middle deltoid force increased a mean of 26% (p = 0.04). Scapular plane elevation may still be possible following an RTSR in the setting of anterior deltoid deficiency. When the anterior deltoid is deficient, there is a compensatory increase in the force required by the subscapularis and middle deltoid. Attempts to preserve the subscapularis, if present, might maximise post-operative function


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 270 - 270
1 Mar 2013
Moon J Hong J Kwon H
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Backgrounds. The rigid fixation of glenoid base plate is essential for the prevention of dissociation of the construct in the reverse total shoulder arthroplasty. For the rigid fixation, ideal placement of fixation screw is crucial but it is difficult to determine the best direction and length of screws. The purpose of this study was to determine configuration of optimal screw in cadaveric scapulae and compare with that in patient who underwent reverse total shoulder arthroplasty. Materials and methods. Seven scapulae were used and implanted using a variable angle base plate with four directions screws. Optimal screw placement was defined as that which maximized screw length, accomplished far cortical purchase. Insertion angle and length of every screw was measured from AP and axial radiograph taken after the screws fixation. In a similar manner, the insertion angles of screws were measured from radiographs of 7 postoperative patients who underwent reverse total shoulder arthroplasty. The averages of length and insertion angle of 4 screws from two groups were compared. Result. The average lengths of screws were anterior 29.4 mm, posterior 15.0 mm, superior 36.0 mm, inferior 46.7 mm in the cadavers group and 22.2 mm, 22.3 mm, 28.0 mm, 29.1 mm each in the patient group. There was statistical significance of the difference of the insertion angle of superior and inferior screws between two groups. Conclusion. Trajectory angles of superior and inferior screw were smaller than those of optimal screws. Awareness of this tendency is helpful to insert the optimal screws intraoperatively


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_8 | Pages 35 - 35
10 May 2024
Bolam SM Wells Z Tay ML Frampton CMA Coleman B Dalgleish A
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Introduction. The purpose of this study was to compare implant survivorship and functional outcomes in patients undergoing reverse total shoulder arthroplasty (RTSA) for acute proximal humeral fracture (PHF) with those undergoing elective RTSA in a population-based cohort study. Methods. Prospectively collected data from the New Zealand Joint Registry from 1999 to 2021 and identified 7,277 patients who underwent RTSA. Patients were categorized by pre-operative indication, including acute PHF (10.1%), rotator cuff arthropathy (RCA) (41.9%), osteoarthritis (OA) (32.2%), rheumatoid arthritis (RA) (5.2%) and old traumatic sequelae (4.9%). The PHF group was compared with elective indications based on patient, implant, and operative characteristics, as well as post-operative outcomes (Oxford Shoulder Score [OSS], and revision rate) at 6 months, 5 and 10 years after surgery. Survival and functional outcome analyses were adjusted by age, sex, ASA class and surgeon experience. Results. Implant survivorship at 10 years for RTSA for PHF was 97.3%, compared to 96.1%, 93.7%, 92.8% and 91.3% for OA, RCA, RA and traumatic sequelae, respectively. When compared with RTSA for PHF, the adjusted risk of revision was higher for traumatic sequelae (hazard ratio = 2.29; 95% CI:1.12–4.68, p=0.02) but not for other elective indications. At 6 months post-surgery, OSS were significantly lower for the PHF group compared to RCA, OA and RA groups (31.1±0.5 vs. 35.6±0.22, 37.7±0.25, 36.5±0.6, respectively, p<0.01), but not traumatic sequelae (31.7±0.7, p=0.43). At 5 years, OSS were only significantly lower for PHF compared to OA (37.4±0.9 vs 41.0±0.5, p<0.01), and at 10 years, there were no differences between groups. Discussion and Conclusion. RTSA for PHF demonstrated reliable long-term survivorship and functional outcomes compared to other elective indications. Despite lower functional outcomes in the early post-operative period for the acute PHF group, implant survivorship rates were similar to patients undergoing elective RTSA


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_8 | Pages 12 - 12
1 May 2019
Throckmorton T
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Reverse total shoulder arthroplasty (RTSA) has a proven track record as an effective treatment for a variety of rotator cuff deficient conditions. However, glenoid erosion associated with the arthritic component of these conditions can present a challenge for the shoulder arthroplasty surgeon. Options for treatment of glenoid wear include partial reaming with incomplete baseplate seating, bony augmentation using structural or impaction grafting techniques, and augmented baseplates. Augmented components have the advantage of accommodating glenoid deformity with a durable material and also ream less subchondral bone; both of which may offer an advantage over traditional bone grafting. Biomechanical and early clinical studies of augmented glenoid baseplates suggest they are a reasonable treatment option, though posteriorly augmented baseplates have shown better performance than superiorly augmented implants. However, there are no mid- or late-term studies comparing augmented baseplates to bone grafting or partial reaming. We present a live surgical demonstration of RTSA for a patient with advanced glenoid erosion being treated with an augmented glenoid baseplate that can be dialed in the direction of any deformity (superior, posterior, etc.). This versatility allows the surgeon to place the augment in any direction and is not confined to the traditional concepts of glenoid wear in a single vector. Clearly, longer term follow up studies are needed to determine the ultimate effectiveness of these devices in treating glenoid deformity in RTSA


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_7 | Pages 1 - 1
1 Jul 2020
Paul R Maldonado-Rodriguez N Docter S Leroux T Khan M Veillette C Romeo A
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Reverse total shoulder arthroplasty (RSA) with glenoid bone grafting has become a common option for the management of significant glenoid bone loss and deformity associated with glenohumeral osteoarthritis. Despite the increasing utilization of this technique, our understanding of the rates of bone graft union, complications and outcomes are limited. The objectives of this systematic review are to determine 1) the overall rate of bone graft union, 2) the rate of union stratified by graft type and technique, 3) the reoperation and complication rates, and 4) functional outcomes, including range of motion (ROM) and functional outcome scores following RSA with glenoid bone grafting. A comprehensive search of MEDLINE, Embase, and CINAHL databases was completed for studies reporting outcomes following RSA with glenoid bone grafting. Inclusion criteria included clinical studies with greater than 10 patients, and minimum follow up of one year. Studies were screened independently by two reviewers and quality assessment was performed using the MINORs criteria. Pooled and frequency-weighted means and standard deviations were calculated where applicable. Overall, 15 studies were included, including nine retrospective case series (level IV), four retrospective cohort studies (level III), one prospective cohort study (level II) and one randomized control trial (level I). The entire cohort consisted of 555 patients with a mean age of 71.9±2.1 years and 70 percent female. The mean follow-up was 33.8±9.4 months. Across all procedures, 84.9% (N=471) were primary arthroplasties, and 15.1% (N=84) were revisions. The overall graft union rate was 89.2%, but was higher at 96.1% among studies that used autograft bone (9 studies, N=308). When stratified by technique, bone graft for the purposes of lateralization resulted in a 100% union rate (4 studies, N=139), while eccentric bone grafts used in asymmetric bone loss resulted in a lower union rate of 84.9% (10 studies, N=345). The overall revision rate was 6.5%, and was lowest following primary cases at 1.8% (11 studies, N=393). The pooled mean scapular notching rate was 20.1% (12 studies, N=497). Excluding notching, the pooled mean complication rate was 21.5% for all cases and 13% for primary cases (11 studies, N=393). When reported, there was significant improvement in post-operative ROM in all planes. There was also improvement in functional outcome scores, whereby the frequency-weighted mean Constant score increased from 25.9 to 67.2 (8 studies, N=319), ASES score increased from 34.7 to 75.2 (4 studies, N=142), and SST score increased from 2.1 to 7.6 (5 studies, N=196) at final follow up. This review demonstrates that glenoid bone grafting with RSA results in good mid-term clinical and radiographic outcomes. Union rate appears to depend highly on graft type and technique, whereby the highest union rates were seen following the use of autograft bone for the purposes of lateralization. Interestingly, the union rate of autograft bone for the purposes of augmentation in eccentric bone loss is considerably lower and its impact on the long-term survivorship of the implant remains unknown


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIII | Pages 161 - 161
1 May 2012
Patel M Nara K Nara N Bonato L
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We present a series of 18 consecutive cases of primary reverse total shoulder arthroplasty for irreparable proximal humerus fractures in patients over 70. Failure of tuberosity union and poor cuff function leads to unsatisfactory results in over half the patients with hemiarthroplasty. Reverse total shoulder arthroplasty does not depend upon a functional rotator cuff and requires little formal rehabilitation. Patients over 70 with irreparable proximal humerus fractures treated with a reverse total shoulder arthroplasty were included in this study. Only primary arthroplasties were included. Reverse arthroplasties for failed hemiarthroplasties were excluded. All arthroplasties were performed using either a deltoid split direct lateral (superior) approach or the antero-lateral MacKenzie approach. The SMR reverse total shoulder prothesis was implanted in all cases using a press-fit glenoid base plate and glenosphere, and press-fit or cemented humerus stem. Tuberosity repair was attempted in 10 cases. The supraspinatus was excised from the greater tuberosity. Patients were allowed self-mobilisation after two weeks in a sling. Patients were recruited and followed up per ethics approved protocol. Outcome measures used were range of motion, dislocation and revision rates radiological signs of loosening and glenoid notching, DASH and Constant scores. Results were compared to another series of cases of reverse shoulder arthroplasty for sequelae of trauma and failed hemiarthroplasties, as well as a series of primary hemiarthroplasties. At an average follow-up of 30 months (minimum 12 months) all patients were satisfied with their results. Average forward elevation was 132 deg. and abduction 108 deg. There was not deterioration of movement at 12 or 24 months. No patient had ongoing pain. The average constant score was 62. There was no evidence of humeral stem loosening apart from one case of early subsidence in a press fit stem. Eleven cases showed glenoid notching, four Nerot grade 1, six Nerot grade 2 and one Nerot grade 3. All notching had stabilised after 12 months. There were no cases of dislocation. No case needed revision, or awaits revision. All cases were pain-free at last review. Overall results for this group of primary reverse arthroplasties for fractures was much better than for reverse arthroplasties for sequelae of trauma. The results were also better than for primary hemiarthroplasties. Irreparable three and four part fractures of the proximal humerus pose management challenges in the elderly. The reverse total shoulder arthroplasty is very attractive option for elderly patients with irreparable proximal humerus fractures. They require little rehabilitation and can give reproducibly good functional results, which do not deteriorate with time


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XVI | Pages 5 - 5
1 Apr 2012
Garg S Vasilko P Blacnnall J Kalogrianitis S Heffernan G Wallace W
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Most common current surgical treatment options for cuff tear arthropathy (CTA) are hemiarthroplasty and reverse total shoulder replacement. At our unit we have been using Reverse Total shoulder replacement (TSR) for CTA patients since 2001. We present our results of Reverse TSR in 64 patients (single surgeon) with a mean follow up of 2 years (Range 1 to 8 years). There were 45 males and 19 females in the study with a mean age of 70 years. Preoperative and postoperative Constant scores were collected by a team of specialist shoulder physiotherapists. Preoperatively plain radiographs were used to evaluate the severity of arthritis and bone stock availability. 90% patients showed an improvement in the Constant score post operatively. The mean improvement in Constant score was 25 points. The mean Pain Score (max 15) improved from 6.3 to 11.8; the mean ADL Score (max 20) improved from 6.8 to 12.3; the mean Range of Motion score (max 40) improved from 10.8 to 20.2; but the mean Power Score (max 25) only improved from 0.9 to 4.9. The differences in improvement were statistically significant in each category. A total 6 patients (10%) required 10 revision surgeries for various reasons. Two patients dislocated anteriorly who were treated by open reduction. Two patients required revision of the glenoid component due to loosening after a mean of 2 years. One patient required revision of the humeral component with strut grafting secondary to severe osteolysis. Only one patient required revision of both humeral and glenoid components secondary to malpositioning. Three patients died for reasons unconnected with their shoulder problems and surgery. Radiographic analysis at the latest follow up (mean 24 months) showed inferior glenoid notching in 40% cases. Heterotrophic ossification was not seen in our series. We conclude that reverse TSR is a viable option for treatment of cuff tear arthropathy however glenoid loosening and scapular notching remains an issue


The Bone & Joint Journal
Vol. 100-B, Issue 6 | Pages 761 - 766
1 Jun 2018
Holschen M Siemes M Witt K Steinbeck J

Aims. The reasons for failure of a hemirthroplasty (HA) when used to treat a proximal humeral fracture include displaced or necrotic tuberosities, insufficient metaphyseal bone-stock, and rotator cuff tears. Reverse total shoulder arthroplasty (rTSA) is often the only remaining form of treatment in these patients. The aim of this study was to evaluate the clinical outcome after conversions from a failed HA to rTSA. Material and Methods. A total of 35 patients, in whom a HA, as treatment for a fracture of the proximal humerus, had failed, underwent conversion to a rTSA. A total of 28 were available for follow-up at a mean of 61 months (37 to 91), having been initially reviewed at a mean of 20 months (12 to 36) postoperatively. Having a convertible design, the humeral stem could be preserved in nine patients. The stem was removed in the other 19 patients and a conventional rTSA was implanted. At final follow-up, patients were assessed using the American Shoulder and Elbow Surgeons (ASES) score, the Constant Score, and plain radiographs. Results. At final follow-up, the mean ASES was 59 (25 to 97) and the mean adjusted Constant Score was 63% (23% to 109%). Both improved significantly (p < 0.001). The mean forward flexion was 104° (50° to 155°) and mean abduction was 98° (60° to 140°). Nine patients (32%) had a complication; two had an infection and instability, respectively; three had a scapular fracture; and one patient each had delayed wound healing and symptomatic loosening. If implants could be converted to a rTSA without removal of the stem, the operating time was shorter (82 minutes versus 102 minutes; p = 0.018). Conclusion. After failure of a HA in the treatment of a proximal humeral fracture, conversion to a rTSA may achieve pain relief and improved shoulder function. The complication rate is considerable. Cite this article: Bone Joint J 2018;100-B:761–6


The Bone & Joint Journal
Vol. 98-B, Issue 1 | Pages 65 - 74
1 Jan 2016
Phadnis J Huang T Watts A Krishnan J Bain GI

Aims. To date, there is insufficient evidence available to compare the outcome of cemented and uncemented fixation of the humeral stem in reverse shoulder arthroplasty (RSA). . Methods. A systemic review comprising 41 clinical studies was performed to compare the functional outcome and rate of complications of cemented and uncemented stems in RSA. These included 1455 cemented and 329 uncemented shoulders. The clinical characteristics of the two groups were similar. Variables were compared using pooled frequency-weighted means and relative risk ratios (RR). Results. Uncemented stems had a significantly higher incidence of early humeral stem migration (p < 0.001, RR 18.1, 95% confidence interval (CI) 5.0 to 65.2) and non-progressive radiolucent lines (p < 0.001, RR 2.4, 95% CI 1.7 to 3.4), but a significantly lower incidence of post-operative fractures of the acromion compared with cemented stems (p = 0.004, RR 14.3, 95% CI 0.9 to 232.8). There was no difference in the risk of stem loosening or revision between the groups. The cemented stems had a greater relative risk of infection (RR 3.3, 95% CI 0.8 to 13.7), nerve injury (RR 5.7, 95% CI 0.7 to 41.5) and thromboembolism (RR 3.9, 95% CI 0.2 to 66.6). The functional outcome and range of movement were equivalent in the two groups. . Discussion. RSA performed with an uncemented stem gives them equivalent functional outcome and a better complication profile than with a cemented stem. The natural history and clinical relevance of early stem migration and radiolucent lines found with uncemented stems requires further long-term study. Take home message: This study demonstrates that uncemented stems have at least equivalent clinical and radiographic outcomes compared with cemented stems when used for reverse total shoulder arthroplasty. . Cite this article: Bone Joint J 2016;98-B:65–74


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_7 | Pages 67 - 67
1 Jul 2020
Pelet S Pelletier-Roy R
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Surgeries for reverse total shoulder arthroplasty (RTSA) significantly increased in the last ten years. Initially developed to treat patients with cuff tear arthropathy (CTA) and pseudoparalysis, wider indications for RTSA were described, especially complex proximal humerus fractures. We previously demonstrated in patients with CTA a different sequence of muscular activation than in normal shoulder, with a decrease in deltoid activation, a significant increase of upper trapezius activation and slight utility of the latissimus dorsi. There is no biomechanical study describing the muscular activity in patients with RTSA for fractures. The aim of this work is to describe the in vivo action of RTSA in patients with complex fractures of the proximal humerus. We conducted an observational prospective cohort study comparing 9 patients with RTSA for complex humerus fracture (surgery more than 6 months, healed tuberosities and rehabilitation process achieved) and 10 controls with normal shoulder function. Assessment consisted in a synchronized analysis of range of motion (ROM) and muscular activity on electromyography (EMG) with the use of 7 bipolar cutaneous electrodes, 38 reflective markers and 8 motion-recording cameras. Electromyographic results were standardized and presented in muscular activity (RMS) adjusted with maximal isometric contractions according to the direction tested. Five basic movements were evaluated (flexion, abduction, neutral external rotation, external rotation in 90° of abduction and internal rotation in 90° of abduction). Student t-test were used for comparative descriptive analysis (p < 0,05). The overall range of motion with RTSA is very good, but lower than the control group: flexion 155.6 ± 10 vs 172.2 ± 13.9, p<0.05, external rotation at 90° 55.6 ± 25 vs 85.6 ± 8.8, p<0,05, internal rotation at 90° 37.8 ± 15.6 vs 52.2 ± 12, p<0,05. The three heads of the deltoid are more stressed during flexion and abduction in the RTSA group (p. The increased use of the 3 deltoid chiefs does not support the hypothesis proposed by Grammont when the RTSA is performed for a complex proximal humerus fracture. This can be explained by the reduced dispalcement of the rotation center of the shoulder in these patients compared to those with CTA. These patients also didn't present shoulder stiffness before the fracture. The maximal muscle activity of the trapezius in flexion and of the latissimus dorsi in flexion and abduction had not been described to date. These new findings will help develop better targeted rehabilitation programs. In addition, the significant role of the latissimus dorsi must question the risks of its transfer (L'Episcopo procedure) to compensate for external rotation deficits


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_1 | Pages 99 - 99
1 Feb 2020
Carducci M DeVito P Menendez M Zimmer Z Levy J Jawa A
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Background. Stress fracture of the acromium and scapular spine is a common complication following reverse total shoulder arthroplasty (RSA), with a reported incidence of 3.1%–11%. There is some evidence associating osteoporosis with increased risk of acromial stress fractures, but little else is known about the causes of acromial stress fractures after RSA. This study aims to define better preoperative factors, including demographics, comorbidities, and diagnoses, which predispose patients to postoperative acromial stress fractures. Methods. We retrospectively identified patients who underwent primary or revision RSA for any indication between January 2013 and December 2018 by two surgeons at two separate hospitals. Stress fractures of the acromion were identified on plain radiographs or computed tomography, when necessary. Patient demographics, comorbidities, and surgical indications were compared between patients with and without acromial stress fractures. Results. A total of 1,488 arthroplasties were identified and met the inclusion criteria. Of the study sample, 54 patients were diagnosed with a postoperative acromial stress fracture, an incidence of 3.6%. Patients in the stress fracture cohort were significantly more likely to have preoperative rotator cuff pathology (p<0.001), be of female gender (p<0.001), older (p=0.002), and osteoporotic (p<0.001; Table I). Thyroid disease (p=0.045) and inflammatory or rheumatoid arthritis (p=0.02) were also more frequent among patients with acromial stress fractures (Table I). No other comorbidities, including obesity (p=0.21) and diabetes (p=0.58), correlated significantly with postoperative acromial stress fracture (Table I). Conclusions. Old age, female gender, diagnosed osteoporosis, inflammatory arthritis, thyroid disease, and preoperative rotator cuff deficiency may all be risk factors for postoperative acromial stress fractures. Given that rotator cuff pathology is among the predominant indications for RSA, further research is required to determine the etiology and biomechanical basis for acromial stress fractures. For any figures or tables, please contact the authors directly


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_5 | Pages 15 - 15
1 Apr 2018
Walker D Kinney A Banks S Wright T
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Musculoskeletal modeling techniques simulate reverse total shoulder arthroplasty (RTSA) shoulders and how implant placement affects muscle moment arms. Yet, studies have not taken into account how muscle-length changes affect force-generating capacity postoperatively. We develop a patient-specific model for RTSA patients to predict muscle activation. Patient-specific muscle parameters were estimated using an optimization scheme calibrating the model to isometric arm abduction data at 0°, 45°, and 90°. We compared predicted muscle activation to experimental electromyography recordings. A twelve-degree of freedom model with experimental measurements created patient-specific data estimating muscle parameters corresponding to strength. Optimization minimized the difference between measured and estimated joint moments and muscle activations, yielding parameters corresponding to subjects' strength that can predict muscle activation and lengths. Model calibration was performed on RTSA patients' arm abduction data. Predicted muscle activation ranged between 3% and 70% of maximum. The maximum joint moment produced was 10 Nm. The model replicated measured moments accurately (R. 2. > 0.99). The optimized muscle parameters produced feasible muscle moments and activations for dynamic arm abduction when using data from isometric force trials. A normalized correlation was found between predicted and experimental muscle activation for dynamic abduction (r > 0.9); the moment generation to lift the arm was tracked (R. 2. = 0.99). Statement of Clinical Significance: We developed a framework to predict patient-specific muscle parameters. Combined with patient-specific models incorporating joint configurations, kinematics, and bone anatomy, they can predict muscle activation in novel tasks and, e.g., predict how RTSA implant and surgical decisions may affect muscle function


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_5 | Pages 81 - 81
1 Mar 2017
Pelet S Ratte-Larouche M
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Introduction. This paper describes the kinetic and electromyographic contribution of principal muscles around the shoulder of a cohort of patients with reverse total shoulder arthroplasty (RTSA). Surgeries for RTSA significantly increased in the last five years. Initially developed to treat patients with cuff tear arthropathy and pseudoparalysis, wider indications for RTSA were described (massive non repairable rotator cuff tears, complex 4-parts fractures). Since Grammont's theory in 1985, the precise biomechanics of the RTSA has not yet been demonstrated in vivo. Clinical results of patients with RSTA are still unpredictable and vary one from another. Methods. We conducted an observational prospective cohort study comparing 9 patients with RTSA (surgery more than 6 months and rehabilitation process achieved) and 8 controls with normal shoulder function adjusted for age, sex and dominance. Assessment consisted in a synchronized analysis of range of motion (ROM) and muscular activity on electromyography (EMG) with the use of 7 bipolar cutaneous electrodes, 38 reflective markers and 8 motion-recording cameras. Electromyographic results were standardized and presented in muscular activity (RMS) adjusted with maximal isometric contractions according to the direction tested. Five basic movements were evaluated (flexion, abduction, neutral external rotation, external rotation in 90° of abduction and internal rotation in 90° of abduction). Student t-test were used for comparative descriptive analysis (p<0,05). Results. ROM is limited in the RSTA group (flexion 128,5 vs 152,6, p=0,04; abduction 150 vs 166, p=0,02; neutral ext rot 28.3 vs 75.6, p<0,01; 90° ext rot 26,43 vs 70,63, p<0,01, int rot 27.5 vs 49.4, p=0,01). Anterior and middle deltoid shows less muscular activation in RTSA than in controls, sustaining the deltoid potentiation described by Grammont. Posterior deltoid shows decreased activity in external rotation movements in RTSA. Upper trapezius is the main activator in all directions with an early and constant activity in RTSA (p<0,01). Latissimus dorsi demonstrates increased muscular activity in internal rotation with RTSA (p<0,01). Discussion. The sequence of muscular activation in RTSA is different than in normal shoulder. Grammont's theory is confirmed with this study. The significant contribution of both the trapezius and latissimus dorsi has never been described until today. New rehabilitation protocols targeted on those muscle groups could demonstrate better and more homogenous clinical results


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_21 | Pages 9 - 9
1 Dec 2016
Mellano C Chalmers P Mascarenhas R Kupfer N Forsythe B Romeo A Nicholson G
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Patients over 70 years old have subclinical or impending rotator cuff dysfunction, raising concern about TSA in this population. The purpose of this study is to examine whether reverse total shoulder arthroplasty (RTSA) should be considered for the treatment of glenohumeral osteoarthritis in the presence of an intact rotator cuff (GHOA+IRC in patients older than 70 years of age. Twenty-five elderly (>70 years) patients at least one year status-post RTSA for GHOA+IRC were matched via age, sex, body mass index, smoking status, and whether the procedure involved the dominant extremity with 25 GHOA+IRC patients who received anatomic total shoulder arthroplasty (TSA). Standardised outcome measures, range of motion, and treatment costs were compared between the two groups. Treatment cost was assessed using implant and physical therapy costs as well as reimbursement. Patients who received RTSA for GHO+IRC had significantly lower pre-operative active forward elevation (AFE, 69° vs. 98°, p <0.001) and experienced a greater change in AFE (p=0.01), but had equivalent AFE at final follow-up (140° vs. 142°, p=0.71). Outcomes were otherwise equivalent between groups with no differences. In both those patients who underwent TSA and those that underwent RTSA, significant improvements between pre-operative and final follow-up were seen in all standardised outcome measures and in AFE (p<0.001 in all cases). RTSA provided these outcomes at a cost savings of $2,025 in Medicare reimbursement due to decreased physical therapy costs. In patients over the age of 70 with GHOA+IRC, RTSA provides similar improvement in clinical outcomes to TSA at a reduced cost while avoiding issues related to the potential for subclinical or impending rotator cuff dysfunction


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_15 | Pages 20 - 20
1 Aug 2017
Krishnan S
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Reverse total shoulder arthroplasty (TSA) has demonstrated success in restoring active elevation for patients with rotator cuff dysfunction (with or without arthritis). However, recovery of active external rotation after reverse TSA has demonstrated variable success. Transfer of the latissimus dorsi has shown promise in restoring active external rotation in those patients with profound external rotation deficits. The combined latissimus transfer and reverse TSA procedure is intra-operatively challenging and fraught with post-operative complications. Technical details and precise indications are necessary to produce the best chance of success with this operation


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_7 | Pages 103 - 103
1 Jul 2020
Sheth U Nelson P Kwan C Tjong V Terry M
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Traditionally, open reduction and internal fixation (ORIF) and hemiarthroplasty (HA) have been the surgical treatments of choice for displaced proximal humerus fractures (PHF) despite high rates of fixation failure and tuberosity nonunion, especially in the elderly population with poor bone quality. Recently, there has been a significant increase in the use of reverse total shoulder arthroplasty (RTSA) as a treatment option in both acute fractures, as well as a salvage procedure for fracture sequelae (i.e., malunion, nonunion, fixation failure, tuberosity non-union). Despite the growing enthusiasm it remains unknown whether functional outcomes after RTSA as a salvage procedure are similar to those following acute RTSA. As a result, the purpose of this systematic review was to compare functional outcomes after RTSA as a primary versus salvage procedure for displaced PHF in the elderly. A literature search of the electronic databases EMBASE, MEDLINE, and PubMed was conducted to identify all studies comparing RTSA as a primary treatment for displaced PHF and as a salvage procedure for failed initial management. Only studies with a minimum follow-up of two years were included. Data pertaining to range of motion, patient reported outcome measures and complications were extracted from eligible studies and entered into a meta-analysis software package (RevMan version 5.1, The Cochrane Collaboration) for pooled analysis. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of eligible studies. The search identified four studies consisting of 200 patients with a mean age of 73.3 years and a mean follow-up of 3.2 years. There were a total of 76 patients (75% female) who underwent acute RTSA following displaced PHF, while 124 patients (77% female) required salvage RTSA for failure of initial treatment. Primary RTSA was found to have significantly higher American Shoulder and Elbow (ASES) (P = 0.04), Constant (P = 0.01) and University of California at Los Angeles (UCLA) (P = 0.0004) scores compared to salvage RTSA. Forward flexion (P = 0.001) and external rotation (P< 0.0001) were significantly greater amongst those undergoing RTSA acutely versus as a salvage procedure. The odds of having a complication (e.g., infection, dislocation, fracture) were 76% lower amongst those who had primary RTSA compared to salvage RTSA (P = 0.02). The overall quality of eligible studies was moderate to high. Based on the current available evidence, elderly patients with displaced PHF have significantly greater range of motion, higher patient reported outcomes and lower risk of complications with primary RTSA compared to those undergoing RTSA as a salvage procedure. Additional prospective studies are warranted to confirm these findings


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_3 | Pages 92 - 92
1 Feb 2017
Day J MacDonald D Kraay M Rimnac C Williams G Abboud J Kurtz S
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Utilization of reverse total shoulder arthroplasty (RTSA) has steadily increased since its 2003 introduction in the American market. Although RTSA was originally indicated for elderly, low demand patients, it is now being increasingly used to treat rotator cuff arthropathy, humeral fractures, neoplasms and failed total and hemi shoulder arthroplasty. There is, therefore, a growing interest in bearing surface wear of RTSA polyethylene humeral liners. In the current study, we examined humeral liners retrieved as part of an IRB approved study to determine the amount of bearing surface wear. We hypothesized that wear of the bearing surface by intentional contact with the glenosphere (mode I) would be minor compared to that produced by scapular notching and impingement of the humeral liner (mode II). Twenty-three retrieved humeral liners were retrieved at revision surgery after an average of 1.5 years implantation time. The average age at implantation was 68 years (range 50–85). Shoulders were revised for loosening (7), instability (6), infection (6), pain (2), and other/unknown reasons (2). The liners were scanned using microCT at a resolution of 50 µm and then registered against unworn surfaces to estimate the bearing surface wear depth. The depth of surface penetration due to impingement of the liner with surrounding structures was measured and the location of the deepest penetration was noted. Mode I wear of the bearing surface was detectable for five of the retrieved liners. The penetration depth was 100 µm or less for four of the liners and approximately 250 microns for the fifth liner. It was noted that the liners with discernable mode I wear were those with longer implantation times (average 2.4 years). Material loss and abrasion of the rim due to mode II wear was noted with measurable penetration in 18 of the liners. Mode II wear penetrated to the bearing surface in 11 liners. It was generally noted that volumetric material loss was dominated by mode II wear (Figure 1). In this study of short to medium term retrieved RTSA humeral liners, mode I wear of the bearing surface was a minor source of material loss. Mode II wear due to scapular notching or impingement of the rim was the dominant source of volumetric wear. This is in agreement with a previous study that we have performed on a smaller cohort of seven liners. It is noteworthy that we were able to detect measurable mode I wear for liners with moderate implantation times. The quantity of bearing surface wear that will be seen in long term retrievals remains unknown at this time


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_6 | Pages 138 - 138
1 Jul 2020
Bois A Knight P Alhojailan K Bohsali K Wirth M
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A reverse total shoulder arthroplasty (RSA) is frequently performed in the revision setting. The purpose of this study was to report the clinical outcomes and complication rates following revision RSA (RRSA) stratified according to the primary shoulder procedure undergoing revision, including failed hemiarthroplasty (HA), anatomic total shoulder arthroplasty (TSA), RSA, soft tissue repair (i.e., rotator cuff repair), and open reduction internal fixation (ORIF). A systematic review of the literature was performed using four databases (EMBASE, Medline, SportDISCUS, and Cochrane Controlled Trials Register) between January 1985 and September 2017. The primary outcomes of interest included active range-of-motion (ROM), pain, and functional outcome measures including the American Shoulder and Elbow Surgeons Score (ASES), Simple Shoulder Test (SST), and Constant-Murley (CS) Score. Secondary outcomes included complication rates, such as infection, dislocation, perioperative fracture, base plate failure, neurovascular injury, soft tissue injury, and radiological evidence of scapular notching. Clinical outcome data was assessed for differences between preoperative and postoperative results and complication results were reported as pooled complication rates. Forty-five studies met the inclusion criteria for analysis, which included 1,016 shoulder arthroplasties with a mean follow-up of 45.2 months (range, 31.1 to 57.2 months) (Fig. 1). The mean patient age at revision was 60.2 years (range, 36 to 65.2 years). Overall, RSA as a revision procedure for failed HA revealed favorable outcomes with respect to forward elevation (FE), CS pain, ASES, SST, and CS outcome assessment scores, with mean improvements of 52.5° ± 21.8° (P = < 0 .001), 6.41 ± 4.01 SD (P = 0.031), 20.1 ± 21.5 (P = 0.02), 5.2 ± 8.7 (P = 0.008), and 30.7 ± 9.4 (P = < 0 .001), respectively. RSA performed as a revision procedure for failed TSA demonstrated an improvement in the CS outcome score (33.8 ± 12.4, P = 0.016). RSA performed as a revision procedure for failed soft tissue repair demonstrated significant improvements in FE (60.2° ± 21.2°, P = 0.031) and external rotation (20.8° ± 18°, P = 0.016), respectively. Lastly, RSA performed as a revision procedure for failed ORIF revealed favorable outcomes in FE (61° ± 20.2°, P = 0.031). There were no significant differences noted in RSA performed as a revision procedure for failed RSA, or when performed for a failed TSA, soft tissue repair, and ORIF in any other outcome of interest. Pooled complication rates were found to be highest in failed RSA (10.9%), followed by soft tissue repair (7.1%), HA (6.8%), TSA (5.4%) and ORIF (4.7%). When compared to other revision indications, RRSA for failed HA demonstrated the most favorable outcomes, with significant improvements in ROM, pain, and in several outcome assessments. Complication rates were determined and stratified as per the index procedure undergoing RRSA, patients undergoing revision of a failed RSA were found to have the highest complication rates. With this additional information, orthopaedic surgeons will be better equipped to provide preoperative education regarding the risks, benefits and complication rates to those patients undergoing a RRSA. For any figures or tables, please contact authors directly


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_5 | Pages 27 - 27
1 Mar 2017
Moon J Kim J Shon W
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Introduction. Proper positioning of the baseplate and optimal screw placement are necessary to avoid loosening or failure of the glenoid component in RTSA. Several in vitro and anatomic studies have documented ideal number, size, length and angulation of baseplate screws. However, such fixation can often be tenuous, as the anatomy of scapula bone varies. Furthermore, it can be difficult to identify regions with the best bone stock intraoperatively even though surgeons have an understanding of scapular anatomy with potential screw trajectories in mind. This often leads to variable screw lengths and angulations in the clinical setting. The purpose of this study was to measure optimal screw lengths and angles to reach ideal regions in cadaveric scapulae and to compare the clinical experiences of three surgeons with each other and against a cadaveric model with screw lengths and angulations. Materials and Methods. Seven cadaveric scapulae were used as the template for optimal screw angulation and length for baseplate implantation. Total 21 cases (seven cases of each 3 surgeons) of reverse total shoulder arthroplasty using the Aequalis®-Reversed shoulder prosthesis (Tornier, France) were included. Measurement of screw angulation was done on the AP and axillary views to account for the superior-inferior and the antero-posterior angulations, respectively. The screw lengths used on each scapula was recorded prior to insertion in cadavers and retrieved from the operative records in clinical cases. Screws directed anteriorly and superiorly were recorded as positive values while posteriorly and inferiorly directed screws were designated negative values. The significant differences in degrees of screw angulation and screw lengths among the 3 surgeon groups were calculated using the ANOVA, with the p value at 0.05. The Mann-Whitney U test was performed to evaluate the cadaver group against the surgeon groups. Results. In cadaveric specimens, the averages of the screw lengths used were 29.4 mm (anterior screw), 15.4 mm (posterior screw), 36.0 mm (superior screw), and 46.70 mm (inferior screw). The anterior screw was directed 6.9° inferior and 7.5° degrees posterior in reference to the central peg. The posterior screw direction was inferior (−5.0°) and posterior (−1.7°); Superior screw was directed superiorly (30.1°) and anteriorly (22.2°), while the inferior screw was aimed inferiorly (−15.3°) and posteriorly (−8.3°). In clinical cases, the differences in screw length among the 3 surgeon groups were not statistically significant. There was no significant difference in screw angulation among the 3 surgeons except posterior screw. Comparing cadaveric specimens from the clinical cases, the anterior screws were shorter and directed more superiorly and anteriorly in the patients, and the superior and inferior screws were directed less superiorly and inferiorly in the patient. Conclusion. We concluded that more vertical screw placement of the superior and inferior screws is necessary to obtain the ideal baseplate fixation


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_20 | Pages 7 - 7
1 Nov 2016
Elwell J Willing R
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Failure of reverse total shoulder arthroplasty (rTSA) due to loosening of the metaglene remains a concern. The metaglene is typically affixed to the glenoid via four peripheral bone screws, and the orientations of these screws can affect the stability of the metaglene. The purpose of this finite element analysis (FEA) study was to investigate whether screw orientations should be considered on a patient-specific basis to maximise early fixation. Three-dimensional geometries of four scapula specimens were obtained by segmenting from CT data in 3D Slicer. A metaglene and four rigidly attached 4.5 mm diameter, 18 mm long cylinders representing screws, were placed on each reamed glenoid. Each screw was placed at one of four orientations, 15° or 7.5° toward or away from the central axis of the metaglene face, while all others were held in the baseline (BL) configuration, where all screws were perpendicular to the metaglene face. Finite element models were created by meshing with linear tetrahedral elements. Material properties of titanium (E=113.8 GPa, v=0.34) were applied to the metaglene and screws. Cortical bone material properties were considered uniform (E=17.5 GPa, ν=0.3) while cancellous bone material properties were non-uniform and mapped on an element-by-element basis using CT attenuation data. The scapula was fully constrained, and a 252 N superiorly oriented shear force was applied to the inferior portion of the metaglene. Contact was modelled at bone-implant and bone-screw interfaces. Displacements of the metaglene with respect to the glenoid were measured. The orientations of each screw that minimised in-plane displacement were used for specimen-specific (SS) configurations. A global (GL) configuration was also defined based on the averages of SS orientations. FE model-predicted metaglene displacements of the SS, GL, and BL screw configurations were compared using paired t-tests. The average in-plane metaglene displacements for the SS, GL, and BL configurations were 4.8 ± 1.2, 6.5 ± 3.7, and 5.3 ± 1.5 um, respectively. SS configurations significantly decreased displacements by −0.4 ± 0.3 um (−8.5%, p = 0.024) when compared to BL, but the difference of −1.6 ± 3.1 um (25.3%, p = 0.187) was not significant when compared to the GL configuration. In general, the SS configurations resulted in smaller metaglene displacements than the GL configurations, however the difference was not statistically significant. In one specimen, the GL configuration resulted in abnormally large displacements. These results indicate that, while on average, patient-specific orientations won't yield significantly greater fixation than global configurations; non-patient-specific configurations can, in some cases, yield poor results. Therefore, to ensure optimal fixation for all patients, screw orientations should be considered on a patient-specific basis


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 114 - 114
1 Mar 2013
Li X Knutson Z Choi D Lipman J Craig EV Warren R Gulotta L
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Introduction. While shoulder elevation can be reliably restored following reverse total shoulder arthroplasty (RTSA), patients may experience a loss of internal and external rotation. Several recent studies have investigated scapular notching and have made suggestions regarding glenosphere placement in order to minimize its occurrence. However, very few studies have looked at how changes in glenosphere placement in RTSA affect internal and external rotation. The purpose of this study was to determine the effect of glenosphere position on internal and external rotation range of motion at various degrees of scaption following RTSA. We hypothesized that alteration in glenosphere position will affect the amount of impingement-free internal and external rotation. Methods. CT scans of the scapula and humerus were obtained from seven cadaver specimens and 3-Dimensional (3D) reconstructions were created. A corresponding 3D RTSA model was created by laser scanning the baseplate, glenosphere, humeral stem and bearing. The RTSA models were then virtually implanted into each specimen. The glenosphere position was determined in relation to the neutral position in 6 different settings: Medialization (5 mm), lateralization (10 mm), superior translation (6mm), inferior translation (6 mm), superior tilt (20°), and inferior tilt (15° and 30°). The humerus in each virtual model was allowed to freely rotate at a fixed scaption angle until encountering bone-bone or bone-implant impingement (180 degrees of limitation). Each model was tested at 0, 20, 40, and 60 degrees of scaption and the impingement-free internal and external rotation range of motion for each scaption angle was recorded. Results. At 0Ëš scaption, only inferior translation, lateralization, and inferior tilt allowed any impingement-free motion in IR and ER. At mid ranges of scaption (20Ëš and 40Ëš) a predictable pattern was seen in which increased lateralization and inferior translation resulted in improved rotation. Supraphysiologic motion (>90Ëš rotation) was seen consistently at 60Ëš of scaption in internal rotation. Both superior and inferior tilt positions resulted in increased ROM in the mid-range of scaption. Acromial impingement was seen when the glenosphere was medialized, superiorly translated and with a superior tilt. Superior translation (6 mm) resulted in no rotation at 0 and 20 degrees of scaption (both IR and ER). Figure 1 and 2: Represents the amount of internal (fig. 1) and external rotation (fig. 2) range of motion measured to bony impingement. 180 degrees was set as the physiologic limit for all measurements. Conclusion. Glenosphere position significantly affected humeral internal and external rotation after Reverse Total Shoulder Arthroplasty in our computer model. Inferior translation (6 mm) or lateralization (10 mm) appears to have the most beneficial effects to internal and external rotation of the shoulder. Inferior tilt (15° and 30°) of the glenosphere also improved overall arc of motion in IR and ER when compared to superior tilt and neutral positions. Superior translation (6 mm) and medialization (5 mm) of the glenosphere caused marked limitations in internal and external rotation due to scapular notching and acromial impingement


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_30 | Pages 15 - 15
1 Aug 2013
McLennan K Wells J Spence S Brooksbank A
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Reverse total shoulder arthroplasty (RTSA) provides a surgical alternative to conventional shoulder arthroplasty in the rotator cuff deficient shoulder. Short term data has shown consistent improvements in pain and function but higher complication and failure rates have also been reported. The aims of this study were to identify the early and late complications of RTSA, to establish the frequency of glenoid notching, and to assess the post-operative functional outcomes. 21 patients (22 joints) treated with RTSA at Glasgow Royal Infirmary (GRI) between April 2006 and October 2010 were retrospectively reviewed. Indications for surgery included cuff tear arthropathy, revision hemiarthroplasty and fracture malunion. Complication rates were obtained by analysis of follow up data from Bluespier and case notes. Glenoid notching was graded from x-rays by multiple observers using the Sirveaux classification. Outcome was assessed using the Oxford Shoulder Score (OSS) and range of motion (ROM). The complication rate associated with RTSA was 14.3%, effecting 3 patients. One dislocation and 1 ulnar nerve palsy occurred within 30 days post-op. A late complication was represented by 1 dislocation, which required revision. Glenoid notching occurred in 71.4% (15 of 21patients), though the majority had a low Sirveaux classification (grade 1 or 2). OSS increased post-operatively and showed a linear improvement with time (R. 2. = 0.81) and ROM increased significantly post-op compared with pre-op (p<0.001). The complication rate associated with RTSA at GRI was lower than that reported in literature and the outcome was good as defined by ROM and OSS. The rate of glenoid notching was higher than literature reports but the significance of this is unclear as notching may not be associated with loosening


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_1 | Pages 23 - 23
1 Feb 2020
Van De Kleut M Athwal G Yuan X Teeter M
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Introduction. Reverse total shoulder arthroplasty (RTSA) is a semi-constrained joint replacement with an articulating cobalt-chromium glenosphere and ultra-high molecular weight polyethylene (PE). Because of its limited load bearing, surgeons and implant manufacturers have not elicited the use of highly cross-linked PE in the shoulder, and to date have not considered excessive PE wear in the reverse shoulder a primary concern. As the number of shoulder procedures is expected to grow exponentially in the next decade, however, it is important to evaluate how new designs and bearing materials interact and to have an understanding of what is normal in well-functioning joint replacements. Currently, no in vivo investigation into RTSA PE wear has been conducted, with limited retrieval and simulation studies. In vitro and in silico studies demonstrate a large range in expected wear rates, from 14.3 mm. 3. /million cycles (MC) to 126 mm. 3. /MC, with no obvious relationship between wear rate and polyethylene diameter. The purpose of this study is to evaluate, for the first time, both volumetric and linear wear rates in reverse shoulder patients, with a minimum six-year follow-up using stereo radiographic techniques. Methods. To date, seven patients with a self-reported well-functioning Aequalis Reversed II (Wright Medical Group, Edina, MN, USA) RTSA implant system have been imaged (mean years from surgery = 7.0, range = 6.2 to 9). Using stereo radiographs, patients were imaged at the extents of their range of motion in internal and external rotation, lateral abduction, forward flexion, and with their arm at the side. Multiple arm positions were used to account for the multiple wear vectors associated with activities of daily living and the shoulder's six degrees of motion. Using proprietary software, the position and orientation of the polyethylene and glenosphere components were identified and their transformation matrices recorded. These transformation matrices were then applied to the CAD models of each component, respectively, and the apparent intersection of the glenosphere into the PE recorded. Using previously validated in-house software, volumetric and maximum linear wear depth measurements were obtained. Linear regression was used to identify wear rates. Results. The volumetric and linear wear rates for the 36 mm PE liners (n = 5) were 39 mm. 3. /y (r. 2. = 0.86, range = 24 to 42 mm. 3. /y) and 0.09 mm/y (r. 2. = 0.96, range = 0.08 to 0.11 mm/y), respectively. Only two patients with 42 mm PE liners were evaluated. For these, volumetric and linear wear rates were 110 mm. 3. /y (r. 2. = 0.81, range = 83 to 145 mm. 3. /y) and 0.17 mm/y (r. 2. = 0.99, range = 1.12 to 1.15 mm/y), respectively. Conclusion. For the first time, PE wear was evaluated in the reverse shoulder in vivo. More patients are required for conclusive statements, but preliminary results suggest first order volumetric and linear wear rates within those predicted by simulation studies. It is interesting to note the increased wear with larger PE size, likely due to the increased contact area between congruent faces and the potential for increased sliding distance during arm motion