Influence of design features and brand of reverse shoulder arthroplasties on survivorship and reasons for revision surgery: results of 5,494 arthroplasties with up to 15 years' follow-up reported to the Norwegian Arthroplasty Register 2007-2022.

BACKGROUND AND PURPOSE: We aimed to report the survival of different reverse shoulder arthroplasty (RSA) designs and brands, and factors associated with revision. The secondary aim was to evaluate the reasons for revision. METHODS: We included 4,696 inlay and 798 onlay RSAs reported to the Norwegian Arthroplasty Register (NAR) 2007-2022. Kaplan-Meier estimates of survivorship and Cox models adjusted for age, sex, diagnosis, implant design, humeral fixation, and previous surgery were investigated to assess revision risks. The reasons for revision were compared using competing risk analysis. RESULTS: Overall, the 10-year survival rate was 94% (confidence interval [CI] 93-95). At 5 years all brands exceeded 90%. Compared with Delta Xtend (n = 3,865), Aequalis Ascend Flex (HR 2.8, CI 1.7-4.6), Aequalis Reversed II (HR 2.2, CI 1.2-4.2), SMR (HR 2.5, CI 1.3-4.7), and Promos (HR 2.2, CI 1.0-4.9) had increased risk of revision. Onlay and inlay RSAs had similar risk of revision (HR 1.2, CI 0.8-1.8). Instability and deep infection were the most frequent revision causes. Male sex (HR 2.3, CI 1.7-3.1), fracture sequelae (HR 3.1, CI 2.1-5.0), and fractures operated on with uncemented humeral stems had increased risk of revision (HR 3.5, CI 1.6-7.3). CONCLUSION: We found similar risk of revision with inlay and onlay designs. Some prosthesis brands had a higher rate of revision than the most common implant, but numbers were low.

The Delta III and Delta Xtend reverse shoulder arthroplasty-risk of revision and failure mechanisms: a report on 3650 cases from the Norwegian Arthroplasty Register 1994-2021.

BACKGROUND: The Delta reverse shoulder arthroplasty (RSA) is commonly used worldwide and is the most frequently used RSA in Norway. The aim of this registry-based study was to report 10- and 20-year implant survival, risk of revision, and reasons for revision in 2 consecutive time periods for Delta III (1994-2010) and Delta Xtend (2007-2021) prostheses. METHODS: We included 3650 primary RSAs reported to the Norwegian Arthroplasty Register: 315 Delta III (42% cemented stems) and 3335 Delta Xtend (88% cemented stems). We used Kaplan-Meier analyses to investigate implant survival. The reasons for revision were compared for the 2 designs and fixation technique. Factors that could influence the risk of revision, such as implant design, fixation technique, and patient factors, were investigated using Cox regression analyses with adjustments for age, sex, and diagnosis. RESULTS: Patients operated with Delta III were more likely to be diagnosed with inflammatory disease or fracture sequela, whereas acute fracture, osteoarthritis, and cuff arthropathy were the most frequent indications for Delta Xtend. Ten-year survival was 93.0% (95% confidence interval [CI]: 87.0-99.0) (cemented stem) and 81.6% (95% CI: 75.3-87.9) (uncemented stem) for Delta III and 94.7% (95% CI: 93.3-96.1) (cemented stem) and 95.7% (95% CI: 88.3-100) (uncemented stem) for Delta Xtend. Twenty-year survival for Delta III (uncemented stem) was 68.2% (95% CI: 58.8-77.6). Compared with DeltaXtend (cemented stem) at 10-year follow-up, we found a higher risk of revision for Delta III (uncemented stem) (hazard ratio [HR]: 2.9, 95% CI: 1.7-5.0), whereas no significant difference was found for Delta III (cemented stem) and Delta Xtend (uncemented stem). The most common reason for revision of Delta III (uncemented stem) was glenoid loosening followed by deep infection and instability. Instability was the most frequent revision cause for Delta Xtend (both cemented and uncemented stem). Men had an overall higher revision risk than women (HR: 2.8 [95% CI: 2.0-3.9]), and patients with fracture sequela had increased risk for revision (HR: 2.8, 95% CI: 1.7-4.7) compared with patients with osteoarthritis. DISCUSSION: We found that Delta III (uncemented stem) had a higher risk of revision compared with Delta Xtend (cemented stem). The risk of revision for glenoid component loosening was lower for Delta Xtend, but revisions due to instability/dislocation are still a concern. This register study cannot determine whether the differences found were caused by differences in implant design or other factors that changed during the study period. Risk of revision may have been affected by the indication for primary operation.

Thromboprophylaxis in primary shoulder arthroplasty does not seem to prevent death: a report from the Norwegian Arthroplasty Register 2005-2018.

Background and purpose - There is still no consensus on whether to use thromboprophylaxis as a standard treatment in shoulder replacement surgery. We investigated the use of thromboprophylaxis reported to the Norwegian Arthroplasty Register (NAR). The primary endpoint was early mortality after primary shoulder arthroplasty with and without thromboprophylaxis. Secondary endpoints included revisions within 1 year and intraoperative complications.Patients and methods - This observational study included 6,123 primary shoulder arthroplasties in 5,624 patients reported to the NAR from 2005 to 2018. Cox regression analyses including robust variance analysis were performed with adjustments for age, sex, ASA score, diagnosis, type of implant, fixation, duration of surgery, and year of primary surgery. An instrumental variable Cox regression was performed to estimate the causal effect of thromboprophylaxis.Results - Thromboprophylaxis was used in 4,089 out of 6,123 shoulder arthroplasties. 90-day mortality was similar between the thromboprophylaxis and no thromboprophylaxis groups (hazard ratio (HR) = 1.1, 95% CI 0.6-2.4). High age (> 75), high ASA class (≥ 3), and fracture diagnosis increased postoperative mortality. No statistically significant difference in the risk of revision within 1 year could be found (HR = 0.6, CI 0.3-1.2). The proportion of intraoperative bleeding was similar in the 2 groups (0.2%, 0.3%).Interpretation - We had no information on cause of death and relation to thromboembolic events. However, no association of reduced mortality with use of thromboprophylaxis was found. Based on our findings routine use of thromboprophylaxis in shoulder arthroplasty can be questioned.

Feasibility of the SINEX program for patients with traumatic anterior shoulder instability.

BACKGROUND: An optimal treatment for traumatic anterior shoulder instability (TASI) remains to be identified. A shoulder instability neuromuscular exercise (SINEX) program has been designed for patients with TASI, but has not yet been tested in patients eligible for surgery. The purpose of this study was to investigate and evaluate the feasibility and safety of the SINEX program for patients diagnosed with TASI and eligible for surgery. METHODS: A feasibility study with an experimental, longitudinal design using both quantitative and qualitative research methods. A total of seven participants underwent the SINEX program, a 12-week exercise program including physiotherapist-supervised sessions. Feasibility data on recruitment, retention, compliance, acceptability and safety was collected through observation and individual semi-structured interviews. Clinical tests and self-report questionnaires were completed at baseline and 12 weeks follow-up. Clinical assessments included apprehension and relocation tests, shoulder joint position sense (SJPS), shoulder sensorimotor control measured by center of pressure path length (COPL) on a force platform, isometric strength measured by Constant Score-Isometric Maximal Voluntary Contraction (CS-iMVC), self-report questionnaires including Western Ontario Shoulder Instability Index (WOSI), Tampa Scale of Kinesiophobia (TSK) and Global Perceived Effect questionnaire (GPE). RESULTS: With one participant recruited every 2 weeks, the recruitment rate was 50% lower than expected. Two of seven participants achieved compliance, defined as at least 66% completion of the scheduled home exercises and at least 50% attendance for the physiotherapist supervised sessions. Barriers for successful compliance were (1) inability to take along exercise equipment when travelling, (2) sick leave, (3) holidays and (4) lack of time/busy days. Four adverse events occurred, one of which was related to the intervention (patellar redislocation). All participants expressed satisfaction with the intervention and felt safe during the exercises. All participants improved in the GPE. Change greater than minimal detectable change (MDC) was reported in four participants in some of the outcome assessments. One of the seven participants declined surgery. CONCLUSION: Further assessment is required on several areas before performing an RCT evaluating the efficacy of the SINEX program for patients with TASI considered eligible for surgery. No adverse events suggest that the program is safe, but patients with general hypermobility may need additional adjustments to prevent adverse events in other areas of the body. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04152304, retrospectively registered.

Low arthroplasty survival after treatment for proximal humerus fracture sequelae: 3,245 shoulder replacements from the Nordic Arthroplasty Register Association.

Background and purpose - Proximal humerus fractures (PHF) may result in sequelae indicating arthroplasty. We report cumulative survival rates and reasons for revision after arthroplasty for proximal humerus fracture sequelae (PHFS).Patients and methods - Data were derived from the Nordic Arthroplasty Register Association. The Kaplan-Meier method was used to illustrate survival rates. A scaled Schoenfeld residual plot was used to report the risk of revision for men relative to women in patients who were treated with reverse shoulder arthroplasty (RSA). Revision was defined as removal or exchange of any component or the addition of a glenoid component.Results - 30,190 primary arthroplasties were reported from 2004 to 2016, of which 3,245 were for PHFS. The estimated 1-, 5-, and 10-year cumulative survival rates (95% CI) were 96% (95-97), 90% (89-92), and 86% (83-88) for stemmed hemiarthroplasty and 94% (92-95), 89% (87-91), and 86% (82-90) for RSA with a median time to revision of 18 months (IQR 9-44) and 3 months (IQR 0-17). The risk of revision for men relative to women in patients who were treated with RSA was 3.2 (1.9-5.1) 0-1 year after surgery and 1.9 (0.9-4.1) 1-8 years after surgery. The estimated 1-, 5-, and 10-year cumulative survival rates (95% CI) were 94% (92-96), 88% (85-90), and 80% (75-86) for men and 95% (94-96), 86% (84-89), and 81% (77-84) for young patients.Interpretation - Shoulder arthroplasty for PHFS was associated with lower survival rates, compared with previously published results of shoulder arthroplasty for acute PHF. The low arthroplasty survival rates for men and young patients especially are worrying.

Low risk of revision after reverse shoulder arthroplasty for acute proximal humeral fractures.

BACKGROUND: Reverse shoulder arthroplasty (RSA) has gained popularity in the treatment of proximal humeral fractures (PHFs), especially in elderly patients. The purpose of this study was to investigate the use of RSA implants for acute PHFs and risk of revision, as well as risk factors for revision. METHODS: RSA implants for acute PHFs were identified from the Nordic Arthroplasty Register Association registry data from 2004 to 2016. Kaplan-Meier survival analysis was used to calculate implant survival. Cox multiple regression analysis was used to calculate the adjusted revision rate for sex, age, country of operation, and year of surgery. RESULTS: The study included 1523 RSA implants for PHFs (84% women; average age, 77 years; average follow-up time, 2.5 years). The 5-year cumulative implant survival rate was 97% (confidence limits, 95.5% and 98%). Revision was performed for 33 implants (2%). The most common reason for revision was instability, occurring in 11 cases (0.7%), followed by fracture, occurring in 6 (0.4%), and infection, occurring in 5 (0.3%). Four different arthroplasty brands were used in this cohort, with the Delta Xtend in two-thirds of cases (n = 1025). Age younger than 60 years and male sex were associated with slightly higher rates of revision; however, these differences did not reach statistical significance (hazard ratio of 2.02 with P = .075 and hazard ratio of 3.23 with P = .057, respectively). CONCLUSION: The use of RSA for acute PHFs is increasing in the Nordic countries. The short-term risk of revision is low. The main reason for revision of RSA for this indication is instability.

The benefits of collaboration: the Nordic Arthroplasty Register Association.

The Nordic Arthroplasty Register Association (NARA) was established in 2007 by arthroplasty register representatives from Sweden, Norway and Denmark with the overall aim to improve the quality of research and thereby enhance the possibility for quality improvement with arthroplasty surgery. Finland joined the NARA collaboration in 2010.NARA minimal hip, knee and shoulder datasets were created with variables that all countries can deliver. They are dynamic datasets, currently with 25 variables for hip arthroplasty, 20 for knee arthroplasty and 20 for shoulder arthroplasty.NARA has published statistical guidelines for the analysis of arthroplasty register data. The association is continuously working on the improvement of statistical methods and the application of new ones.There are 31 published peer-reviewed papers based on the NARA databases and 20 ongoing projects in different phases. Several NARA publications have significantly affected clinical practice. For example, metal-on-metal total hip arthroplasty and resurfacing arthroplasty have been abandoned due to increased revision risk based on i.a. NARA reports. Further, the use of uncemented total hip arthroplasty in elderly patients has decreased significantly, especially in Finland, based on the NARA data.The NARA collaboration has been successful because the countries were able to agree on a common dataset and variable definitions. The collaboration was also successful because the group was able to initiate a number of research projects and provide answers to clinically relevant questions. A number of specific goals, set up in 2007, have been achieved and new one has emerged in the process. Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180058.

The short-term survival of total stemless shoulder arthroplasty for osteoarthritis is comparable to that of total stemmed shoulder arthroplasty: a Nordic Arthroplasty Register Association study.

BACKGROUND: The purpose of this study was to compare the short-term survival rate of total stemless, metaphyseal fixated, shoulder arthroplasty with that of total stemmed shoulder arthroplasty in the treatment of osteoarthritis. METHODS: Data were collected by the national arthroplasty registries in Denmark, Finland, Norway, and Sweden and merged into 1 dataset under the umbrella of the Nordic Arthroplasty Register Association. For the present study, we included all patients with osteoarthritis treated with either stemless (n = 761) or stemmed (n = 4398) shoulder arthroplasty from 2011 to 2016. RESULTS: A total of 21 (2.8%) stemless and 116 (2.6%) stemmed shoulder arthroplasties were revised. The 6-year unadjusted cumulative survival rates were 0.953 for stemless shoulder arthroplasty and 0.958 for stemmed shoulder arthroplasty, P = .77. The most common indication for revision of both arthroplasty types was infection. Five (0.7%) stemless and 16 (0.4%) stemmed shoulder arthroplasties were revised because of loosening of either the glenoid or the humeral component. In the multivariate cox regression model, which included age, category, gender, year of surgery, previous surgery, and arthroplasty type, the hazard ratio (HR) for revision of the stemless shoulder arthroplasty was 1.00 (95% confidence interval [CI], 0.63-1.61), P = .99, with the stemmed shoulder arthroplasty as reference. Male gender (HR = 1.50 [95% CI, 1.06-2.13], P = .02) and previous surgery (HR = 2.70 [95% CI, 1.82-4.01], P < .001) were associated with increased risk of revision. CONCLUSION: The short-term survival of total stemless shoulder arthroplasty appears comparable with total stemmed shoulder arthroplasty, but longer observation time is needed to confirm whether they continue to perform equally.

Risk and risk factors for revision after primary reverse shoulder arthroplasty for cuff tear arthropathy and osteoarthritis: a Nordic Arthroplasty Register Association study.

BACKGROUND: Reverse shoulder arthroplasty (RSA) has gained increasing popularity in the treatment of rotator cuff tear arthropathy (CTA). The purpose of this study was to evaluate the survival of RSA and the risk factors for revision following RSA. METHODS: RSA patients with CTA or osteoarthritis were identified from the Nordic Arthroplasty Register Association registry data (2004-2013). Kaplan-Meier survival analysis was used to calculate survival probabilities. Cox multiple regression analysis was used to calculate revision rates adjusted for sex, arthroplasty brand, age (<70 years), and year of surgery. RESULTS: The study included 1904 patients with RSA (1904 RSAs) (69% women; mean age, 74 years; age range, 35-97 years). Revision was performed in 95 patients (5%), with a 10-year cumulative revision rate of 0.91. The most common reason for revision was infection (n = 42), followed by loosening (n = 16) and instability (n = 12). Most revisions occurred less than 6 months after the primary operation. Men had a significantly increased risk of revision compared with women (risk ratio, 3.8; 95% confidence interval, 2.4-6.1). The most common implants were the Delta Xtend (n = 1366) and Delta Mark III (n = 246). The risk of revision of the Delta Mark III was 2.1 (95% confidence interval, 1.1-4.3) compared with the Delta Xtend. Age and year of surgery were not statistically significantly associated with risk of revision. CONCLUSION: The overall midterm risk of revision after RSA for CTA was low (5%). The most common reason for early revision was infection. Male sex was associated with a significantly increased risk of revision.

Increased risk of revision with hamstring tendon grafts compared with patellar tendon grafts after anterior cruciate ligament reconstruction: a study of 12,643 patients from the Norwegian Cruciate Ligament Registry, 2004-2012.

BACKGROUND: The graft choice for anterior cruciate ligament reconstruction (ACLR) is controversial. Hamstring tendon (HT) autografts and patellar tendon (PT) autografts are the most common grafts used and have shown similar subjective and objective outcomes. PURPOSE: To compare the revision rate between HT and PT autografts used in ACLR in Norway and to estimate the influence of patient age and sex. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: The study included all patients who underwent primary ACLR without concomitant ligament injuries registered in the Norwegian Knee Ligament Registry from 2004 through 2012. The cohort was stratified by age group (15-19, 20-29, and ≥30 years) and autograft type (HT or PT). Revision rates at 1, 2, and 5 years were calculated using the Kaplan-Meier analysis, and hazard ratios (HRs) for revision were calculated using multivariate Cox regression models. RESULTS: With a mean follow-up of 4.0 years, 12,643 primary ACLRs were identified, with 3428 PT and 9215 HT grafts, among which 69 revisions with PT grafts and 362 revisions with HT grafts were performed. The overall 5-year revision rate was 4.2%. A higher revision rate was recorded for HT versus PT grafts at all follow-up times. When adjusted for sex, age, and type of graft, the HR for revision was 2.3 (95% CI, 1.8-3.0) for HT grafts compared with PT grafts. The HR for revision in the youngest age group was 4.0 (95% CI, 3.1-5.2) compared with the oldest age group. Sex had no effect on the revision rate. CONCLUSION: Patients with HT grafts had twice the risk of revision compared with patients with PT grafts. Younger age was the most important risk factor for revision, and no effect was seen for sex. Further studies should be conducted to identify the cause of the increased revision rate found for HT grafts.