Acta Orthopaedica最新文献

Background and purpose: With more knee arthroplasties (KAs) performed in working-age patients, interest in return to work (RTW) increases. We aimed to investigate the association between body mass index (BMI) and RTW after primary KA and whether the association varies by sex, age, comorbidity, and socioeconomic position.

Methods: From Danish national registries, we included 6,128 patients aged 18 to 60 years undergoing KA from 2008-2018. Exposure was BMI in categories < 25.0, 25.0-29.9, 30.0-34.9, 35.0-39.9, and ≥ 40.0. Outcome was RTW after KA. We estimated cumulative incidence proportions (CIP) of RTW. Cox regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CI).

Results: Median time to RTW was 70 days. Overall CIP for RTW was 63% (CI 62-65) at 3 months. With BMI < 25 as reference, CIP was 65% (n = 1,401) for BMI 25.0-29.9, 64% (n = 1,130) for BMI 30.0-34.9, 60% (n = 528) for BMI 35.0-39.9, and 60% (n = 260) for BMI ≥ 40.0, corresponding to an adjusted HR of 1.06 (CI 0.98-1.15), 1.02 (CI 0.94-1.11), 0.97 (CI 0.88-1.06), and 0.96 (CI 0.85-1.08). Men with BMI 35.0-39.9 and ≥ 40 had an adjusted HR of 0.89 (CI 0.76-1.05) and 0.87 (CI 0.70-1.10). None of the associations were statistically significant. Age, comorbidity, and socioeconomic position did not modify the association between BMI and RTW.

Conclusion: More than 60% of patients RTW within 3 months but we found no association between BMI and RTW after primary KA.

Background and purpose:  The number of cancer survivors has increased. Although spine surgery rates have multiplied in the general population, they are understudied in cancer populations. We aimed to determine the incidence rates of spinal surgery for degenerative and traumatic pathologies in patients with prior cancer. Our secondary aim was to define the underlying primary cancer diagnoses and survival rates after spinal procedures.

Methods:  Data was combined from 3 nationwide registers: the Finnish Cancer Register, Finnish Care Register for Health Care, and Finnish Cause of Death Register. Spine surgeries were identified using diagnosis and procedural codes, and tumor surgeries were excluded. Incidence rates were calculated per 100,000 inhabitants and adjusted for age and sex. Kaplan-Meier survival estimates (with 95% confidence intervals [CI]) were calculated per the first spine surgery.

Results:  10,280 patients underwent 12,425 surgeries, with a mean age of 70 years; 53% were women. Degenerative pathologies accounted for 74% of the surgeries, followed by disc pathologies (20%) and trauma (6%). The incidence of spine surgeries increased from 3.7 to 15.1 per 100,000 person-years (300%) between 1997 and 2019. The increase mostly occurred in degenerative spine procedures (420%), whereas disc and trauma surgeries were temporally stable. The most common previously diagnosed cancers were breast (24%) and prostate (22%) cancers. All-cause survival after spine surgery was 94% (CI 94-95) at 1 year, and cancer-specific survival was 90% (CI 0.89-0.91) at 15 years.

Conclusion:  We showed a 300% increase in spine surgeries unrelated to cancer in patients with a history of cancer between 1997 and 2020. Survival rates remained favorable (94% [CI 0.89-0.91] at 1 year).

Background and purpose:  Treatment-related shared decision-making (SDM) in older adults with hip fractures is complex due to the need to balance patient-specific factors such as life goals, frailty, and surgical risks. It includes considerations such as prognosis and decisions concerning whether to operate or not on frail, life-limited patients. We aimed to develop machine learning (ML)-driven prediction models for short- and long-term mortality in a large cohort of patients with hip fractures.

Methods:  In this national registry-based retrospective cohort study, patients aged ≥ 70 years registered in the nationwide Dutch Hip Fracture Audit from 2018-2023 were included. Predictive variables were selected based on the literature and/or clinical relevance. 6 ML algorithms, including logistic regression, were trained with internal cross-validation and evaluated on discrimination (c-statistic), sensitivity, specificity, calibration, and interpretability.

Results:  74,396 patients (median age 84, IQR 78-89; 68% female) were analyzed. Most patients lived at home (69%) and high malnutrition risk was seen in 10%. 18% had dementia. Mortality rates were 9.1% (30-day), 15% (90-day), and 26% (1-year). Logistic regression performed comparably to other algorithms, but was chosen as the preferred algorithm due to its superior interpretability (c-statistic: 30-day 0.82, 90-day 0.81, 1-year 0.80).

Conclusion:  We developed and validated ML algorithms, including logistic regression, for mortality prediction in older hip fracture patients with adequate performance. This information may inform SDM.

Background and purpose:  Our aim was to compare age at time of total hip arthroplasty (THA) and the THA survival time in patients with late-detected developmental dislocation and dysplasia of the hip (DDH) treated with traction in childhood who had either undergone acetabular shelf operation due to persistent DDH, or no previous acetabular surgery but persistent DDH, or no previous acetabular surgery and CE angle ≥ 18°.

Methods:  112 patients (97 females; 144 hips) with late-detected DDH who had undergone THA were studied. 70 hips had undergone a modified Spitzy procedure (SA group) at the age of 8-33 years. They were compared with 2 groups that had not undergone previous pelvic surgery: a "Dysplasia" group with residual (persistent) acetabular dysplasia (CE angle < 18°, 33 hips) and a "Normal" group with no residual dysplasia (37 hips). We analyzed age at THA and the survival rate (percentage of THAs not having undergone revision).

Results:  Mean patient age at THA did not differ between the SA group (52 years) and the Dysplasia group (49 years; P = 0.1). 11 THAs had been revised in the SA group and 9 in the Dysplasia group. Kaplan-Meier analysis showed 20-year survival rates of 88% in the SA group and 68% in the Dysplasia group. The estimated survival time of THA was significantly higher in the SA group than in the Dysplasia group (29.4 and 19.8 years; P = 0.01). Mean age at THA was significantly lower in the Dysplasia group than in the Normal group (49 and 55 years), but there was no significant difference between these groups in estimated survival time of THA.

Conclusion:  A previous acetabular shelf operation in patients with persistent DDH does not appear to delay age at THA but THA had better survival rate.

Background and purpose:  We aimed to externally validate machine learning models developed in Norway by evaluating their predictive outcome of disability and pain 12 months after lumbar disc herniation surgery in a Swedish and Danish cohort.

Methods:  Data was extracted for patients undergoing microdiscectomy or open discectomy for lumbar disc herniation in the NORspine, SweSpine and DaneSpine national registries. Outcome of interest was changes in Oswestry disability index (ODI) (≥ 22 points), Numeric Rating Scale (NRS) for back pain (≥ 2 points), and NRS for leg pain (≥ 4 points). Model performance was evaluated by discrimination (C-statistic), calibration, overall fit, and net benefit.

Results:  For the ODI model, the NORspine cohort included 22,529 patients, the SweSpine cohort included 10,129 patients, and DaneSpine 5,670 patients. The ODI model's C-statistic varied between 0.76 and 0.81 and calibration slope point estimates varied between 0.84 and 0.99. The C-statistic for NRS back pain varied between 0.70 and 0.76, and calibration slopes varied between 0.79 and 1.03. The C-statistic for NRS leg pain varied between 0.71 and 0.74, and calibration slopes varied between 0.90 and 1.02. There was acceptable overall fit and calibration metrics with minor-modest but explainable heterogeneity observed in the calibration plots. Decision curve analyses displayed clear potential net benefit in treatment in accordance with the prediction models compared with treating all patients or none.

Conclusion:  Predictive performance of machine learning models for treatment success/non-success in disability and pain at 12 months post-surgery for lumbar disc herniation showed acceptable discrimination ability, calibration, overall fit, and net benefit reproducible in similar international contexts. Future clinical impact studies are required.

Background and purpose:  Chronic opioid use is of great concern worldwide. Thus, identification of risk factors for new chronic opioid use (COU) after hip and knee arthroplasty is imperative to target preventive strategies. Depression/anxiety may be risk factors for new COU. However, no studies have investigated whether any or subgroups of preoperative psychopharmacological treatments (PPTs) are risk factors for new COU after hip and knee arthroplasty in a nationwide setting, which was the aim of the present study.

Methods:  This population-based cohort study included 40,476 primary hip and 32,557 primary knee arthroplasties from 2015 to 2022 using the Danish Hip/Knee Arthroplasty Registers. Preoperative opioid users were excluded. Dispensing records of psychotropics and opioids were obtained from the Danish National Prescription Registry. Relative risks of new COU were estimated with 95% confidence intervals (CI) using binary regression and adjusted for age, sex, and Charlson Comorbidity Index.

Results:  Among hip patients using psychopharmacological treatments (PPTs), 4.6% (202/4,439) had new COU compared with 2.2% (788/36,037) of patients not using PPTs, corresponding to an adjusted relative risk of 1.8 (CI 1.6-2.1). Among total and unicompartmental knee arthroplasties, 9.1% (298/3,261) and 6.4% (59/926) had new COU compared with 4.7 (1,011/21,529) and 2.9% (201/6,841) of patients not using PPTs, corresponding to adjusted relative risks of 1.8 (CI 1.6-2.1) and 2.0 (CI 1.5-2.7), respectively. Analyses of PPT subgroups showed similar results.

Conclusion:  Hip and knee arthroplasty patients using PPTs have almost a twofold increased risk of new COU. This emphasizes the need for prevention strategies in these patients.

Background and purpose: Backside wear of the polyethylene insert in total knee arthroplasty (TKA) has been described to produce clinically significant levels of polyethylene debris, which can lead to aseptic loosening and osteolysis. Monoblock design eliminates backside wear of the polyethylene and therefore could improve long-term fixation. This randomized clinical trial (RCT) using radiostereometric analysis (RSA) compares micromotion of monoblock and modular polyethylene inserts with 7 years' follow-up.

Methods: 65 patients (mean age 61 years) were randomized to receive either monoblock (n = 32) or modular (n = 33) uncemented trabecular metal tibial components. 35 patients (monoblock = 18, and modular = 17) completed 7 years' follow-up. The primary endpoint of the study was maximum total point motion (MTPM). Implant translation and rotation are reported as secondary endpoints.

Results: After 84 months, the modular group had a statistically significant higher mean MTPM of 1.17 (95% confidence interval [CI] 0.90-1.41) mm compared with the monoblock group of 0.78 (CI 0.55-0.88) mm (P = 0.02). However, there was no difference in continuous migration (from 12-84 months), which was 0.13 mm in the monoblock group and 0.16 mm in the modular group.

Conclusion: There was significantly lower early migration in the monoblock group compared with the modular group but no difference in continuous migration after 12 months, which confirms the finding of previous publications.

Background and purpose:  South Korea has implemented the National Health Screening Program for Infants and Children (NHSPIC), which includes clinical hip screening with selective hip ultrasonography beginning at 4 months of age. We aimed to investigate the trends in developmental dysplasia of the hip (DDH), associated risk factors, and growth and motor developmental outcomes up to preschool age.

Methods:  We included a retrospective, population-based birth cohort of children born between 2008 and 2015. Patients diagnosed with DDH were stratified by age at detection (early diagnosed [<1 year] vs late diagnosed [≥1 year]) and treatment modalities (major surgery, minor surgery, or nonoperative). Growth and motor developmental outcomes were assessed using NHSPIC data collected up to 6 years of age.

Results:  Among 2,518,805 children, 4,854 (0.19%) were diagnosed with DDH. The incidence of DDH increased from 1.29 to 2.37 per 1,000 individuals, with the incidence of early diagnosed DDH increased from 0.70 to 1.94 per 1,000. However, the rate of surgical treatment remained unchanged (0.19-0.28 per 1,000). Children who underwent surgical treatment for DDH had a significantly higher incidences of short stature, and delayed gross motor development.

Conclusion:  After the introduction of the NHSPIC hip screening program, incidences of overall and early diagnosed DDH increased, whereas the surgical treatment rate showed no significant change. Surgical treatment for DDH was significantly associated with both short stature and delayed gross motor development.

Background and purpose:  The New Zealand Joint Registry provides surgeon-level feedback on revision rate and Oxford scores for primary total knee replacement (TKR). Potential outliers are identified using revision rate. Using patient-reported outcome measures to identify outliers, alongside revision rate, could provide a more comprehensive understanding of surgeons' results. We aimed to evaluate using Oxford scores compared with revision rates to identify potential outliers.

Methods:  A registry-based prospective longitudinal cohort design was used. The association between surgeon mean Oxford score at 6 months and revision rate at 2 years, within 5 years, and within 10 years was evaluated using the Pearson correlation coefficient. Funnel and scatter plots were used to compare potential outliers for both measures using control limit and centile outlier thresholds respectively. All TKR in the registry prior to 31 December 2021, performed for any indication, were included.

Results:  There was a weak negative association between mean Oxford score at 6 months and revision rate at 2 years, within 5 years, and within 10 years using the Pearson correlation coefficient. Funnel plot control limits identified similar numbers of outliers for 6-month Oxford score and revision rate, however, there here was minimal overlap in outliers identified using the 2 methods. There was also minimal overlap in outliers using centile thresholds.

Conclusion:  Correlation between Oxford score at 6 months and revision rates is weaker at the surgeon level compared with the patient level. Mean Oxford score identifies different potential outliers compared with revision rates with minimal overlap. This has implications for reporting surgeon-level outcomes, raising questions regarding the most appropriate measure of surgical performance following TKR.

Background and purpose:  The safety and performance of hip and knee prostheses can be assessed by analyzing peer-reviewed literature, registry reports, and safety notices published by national competent authorities/regulatory agencies, or manufacturers. The percentage of hip and knee prostheses with a safety signal published through any of these data sources is unknown. We aimed to assess the frequency of signals identified for a random sample of 10 hip stems, 10 hip cups, and 10 knee implants.

Methods:  3 literature libraries were searched to find safety signals defined as information on patterns/occurrences that may alter the device's benefit-risk profile, reported in peer-reviewed publications for the randomly selected implants. Annual registry reports from 5 national registries were examined to check whether any of the selected implants had outlier performance. The CORE-MD post-market surveillance (PMS) tool was used to collect all related safety notices from 13 competent authority/regulatory agency websites. Manufacturers' websites were screened for any reported safety information.

Results:  Safety signals were identified for 21 of the 30 randomly selected implants: 18 identified by registries, 7 by the CORE-MD PMS tool, and 8 based on literature, with 10 implants identified by multiple sources. There was no systematic pattern in timing of publication with a particular source publishing safety signals earlier than other sources.

Conclusion:  70% of the randomly selected hip and knee prostheses had ≥ 1 safety signals published, with registries as the source for the majority. No single source identified all 21 implants with signals, which highlights the need for a comprehensive surveillance strategy to aggregate safety signals from multiple sources.