Association between additional weekend rehabilitation and functional outcomes in patients with hip fractures: does age affect the effectiveness of weekend rehabilitation?

PURPOSE: Rehabilitation after hip fracture surgery is crucial for improving physical function. Additional rehabilitation over the weekend or after working hours is reportedly associated with improved physical function; however, this may not apply to an aging population, including patients aged > 90 years. This study aimed to investigate the association between additional weekend rehabilitation and functional outcomes in different age groups. METHODS: This study analyzed a cohort of patients aged ≥ 60 years who had hip fractures and were operated on from 2010 to 2018. Data were extracted from a nationwide multicentre database. Functional outcomes at discharge were compared between patients who underwent rehabilitation on weekdays only and those who underwent rehabilitation on both weekdays and weekends. The patient groups were selected using propensity score matching analysis. Furthermore, a subgroup-analysis was conducted on patients in their 60 s, 70 s, 80 s, and 90 s. RESULTS: A total of 390,713 patients underwent surgery during the study period. After matching, each group comprised 129,583 pairs of patients. Patients who underwent weekend rehabilitation exhibited improved physical function in transferring, walking, and stair climbing at discharge, as compared with patients who did not (odds ratio [95% confidence interval]: 1.17 [1.15-1.19], 1.17 [1.15-1.2], and 1.06 [1.03-1.08], respectively). In subgroup analysis, except for stair climbing, the positive association between weekend rehabilitation and patient function was observed across all age groups. CONCLUSION: Weekend rehabilitation was significantly associated with improved physical function. Given the limited healthcare resources, high-demand activities such as stair climbing may be reserved for younger age groups to optimise rehabilitation therapy.

Analysis of survivorship following periacetabular osteotomy for hip dysplasia based on three-dimensional acetabular coverage.

Periacetabular osteotomy (PAO) is an established procedure for correcting acetabular coverage and preventing osteoarthritis progression in hip dysplasia. However, it is unclear how acetabular coverage changes three-dimensionally after PAO and how it affects survival. Therefore, this study aimed to investigate the change in three-dimensional acetabular coverage preoperatively and postoperatively and identify demographic, clinical and radiographic factors associated with conversion to total hip arthroplasty (THA) and radiographic osteoarthritis progression after PAO. We retrospectively reviewed 46 consecutive patients (66 hips) who underwent PAO, using preoperative and postoperative radiographs and pelvic computed tomography (CT). Three-dimensional acetabular coverage based on CT data was investigated. Kaplan-Meier survival analysis was performed, and hazard ratios were calculated using univariate Cox regression models to identify the risk factors associated with conversion to THA and radiographic osteoarthritis progression after PAO as the endpoints. Radiographic osteoarthritis progression was defined as a minimum joint space of <2.0 mm. The mean follow-up was 10.7 years. Post-PAO, acetabular coverage gradually increased from the anterosuperior to the superior to the posterosuperior direction. The survival rate after PAO was 98.0% at 10 years. Less postoperative superior acetabular coverage, with a hazard ratio of 0.93, was significantly associated with conversion to THA and radiographic osteoarthritis progression after PAO (P = 0.03). In this study, poor superior acetabular coverage after PAO was a significant risk factor for conversion to THA and radiographic progression of osteoarthritis. Therefore, surgeons should attempt to prioritize the correction of the superior acetabular coverage when performing PAO.

Time elapsed from definitive diagnosis to surgery for osteonecrosis of the femoral head: a nationwide observational study in Japan.

OBJECTIVES: This study documents the time elapsed from the diagnosis of osteonecrosis of the femoral head (ONFH) to surgery, exploring the factors that influence ONFH severity. DESIGN: Retrospective observational study of a nationwide database. SETTING: The Kaplan-Meier method with log-rank tests was applied to examine the period from definitive diagnosis of ONFH to surgery using any surgery as the end point. For bilateral cases, the date of the first surgery was the endpoint. PARTICIPANTS: This study included 2074 ONFH cases registered in 34 university hospitals and highly specialised hospitals of the multicentre sentinel monitoring system of the Japanese Investigation Committee between 1997 and 2018. MAIN OUTCOME MEASURE: The primary outcome was the time from diagnosis to surgery. The secondary outcome was the proportion of subjects remaining without surgery at 3, 6 and 9 months, and at 1, 2 and 5 years after diagnosis. RESULTS: The median time to surgery was 9 months (IQR 4-22 months) after diagnosis of ONFH. The time to surgery was significantly shorter in the alcohol alone group and the combined corticosteroid and alcohol group than in the corticosteroid alone group (p=0.018 and p<0.001, respectively), in early stage ONFH with no or mild joint destruction (stages II and III, p<0.001), and with joint preserving surgery (p<0.001). The proportion without surgery was 75.8% at 3 months, 59.6% at 6 months, 48.2% at 9 months, 40.5% at 1 year, 22.2% at 2 years and 8.3% at 5 years. CONCLUSION: ONFH has been considered to be an intractable disease that often requires surgical treatment, but the fact that surgery was performed in more than half of the patients within 9 months from diagnosis suggests severe disease with a significant clinical impact. TRIAL REGISTRATION NUMBER: Chiba University ID1049.

Increased bone resorption that outpaces increased bone formation: An important pathology of rapidly destructive coxarthrosis.

Rapid joint destruction caused by rapidly destructive coxarthrosis (RDC) can increase surgical complexity and intraoperative blood loss. This single-center retrospective study investigates osteoporosis-related biomarkers for early RDC diagnosis and explores new treatment targets. We included 398 hip joints from patients who underwent total hip arthroplasty, examining medical records for preoperative patient demographics, bone mineral density of the hip and lumbar spine from dual-energy X-ray absorptiometry scans, and osteoporosis-related biomarkers including TRACP-5b, total P1NP, intact parathyroid hormone, and homocysteine. We compared RDC and osteoarthritis (OA) patients, and univariate analysis showed that RDC patients were older (p < 0.001) and had lower serum levels of albumin (p < 0.001) and higher serum levels of TRACP-5b, total P1NP (p < 0.001), and homocysteine (p = 0.006). Multivariable analysis showed that the ratio of serum TRACP-5b to total P1NP had a more significant difference in RDC patients than in OA patients (p = 0.04). Serum TRACP-5b levels were negatively correlated with the time between RDC onset and blood collection, and Japanese Orthopedic Association pain score. Receiver operating characteristic curve analysis revealed that the ratio of serum TRACP-5b to total P1NP had the highest area under the curve value. This study is the first to demonstrate that the ratio of serum TRACP-5b to total P1NP-increased bone resorption that outpaces increased bone formation-is significantly elevated in patients with RDC and that TRACP-5b is higher in the early stages of RDC. Inhibiting serum levels of TRACP-5b, activated osteoclasts, during early RDC may suppress disease progression.

Analysis of in vivo humeral rotation of reverse total shoulder arthroplasty patients during shoulder abduction on the scapular plane with a load.

BACKGROUND: Few studies have investigated the kinematics after reverse total shoulder arthroplasty (RTSA). This study aimed to compare the shoulder kinematics in RTSA patients during shoulder abduction on the scapular plane with and without a load and yield information regarding the function of stabilizing the joints against gravity for the functional assessment of the shoulder after RTSA, which could lead to changes in postoperative rehabilitation treatment. METHODS: Twenty RTSA patients (7 men, 13 women; mean age: 78.1 [64-90] years) were examined. First, active shoulder abduction in the scapular plane was captured using single-plane fluoroscopic X-ray images. Imaging was performed by stipulating that one shoulder abduction cycle should be completed in 6 s. Two trials were conducted: one under a load equivalent to 2% of body weight and one without a load. Next, a three-dimensional (3D) model of each humeral and scapular component was matched to the silhouette of the fluoroscopic image to estimate the 3D dynamics. By using the 3D dynamic model obtained, the kinematics of the glenosphere and humeral implant were calculated relative to the shoulder abduction angle on the scapular plane and were compared between groups with and without a load. A one-way analysis of variance and a post hoc paired t-test with a statistical significance level of 0.05 were performed. RESULTS: The humeral internal rotation decreased with a load at shoulder abduction between 40° and 90° on the scapular plane (P < 0.01, effect size: 0.15). No significant differences in scapular upward rotation (P = 0.57, effect size: 0.022), external rotation (P = 0.83, effect size: 0.0083) and posterior tilting (P = 0.74, effect size: 0.013) were observed between groups with and without a load. The main effect was not observed with and without a load (P = 0.86, effect size: 0.0072). However, the scapulohumeral rhythm was significantly greater without a load during shoulder joint abduction between 40° and 60° on the scapular plane. CONCLUSION: In RTSA patients, the glenohumeral joint was less internally rotated, and the scapulohumeral rhythm decreased under loaded conditions. It was stabilized against the load through the mechanical advantage of the deltoid muscle and other muscles.

Effect of posteromedial vertical capsulotomy with medial collateral ligament liberation on intraoperative medial component gap mismatch between extension and mid-flexion during total knee arthroplasty.

PURPOSE: The aim of this study was to quantify the effect of posteromedial vertical capsulotomy on intraoperative component gaps and angles from extension through mid-flexion to flexion during total knee arthroplasty (TKA). METHODS: In the present study, 47 cases of primary posterior-stabilized TKA using the measured resection technique for varus knee osteoarthritis (hip-knee-ankle angles < 0°) were reviewed. Component gaps and angles at 0°, 10°, 45°, 90°, and maximum flexion were measured intraoperatively, before and after posteromedial vertical capsulotomy. Differences in pre- and post-posteromedial vertical capsulotomy medial and lateral component gaps and angles and medial component gap mismatches among knee flexion angles were assessed using the Wilcoxon signed rank test for two paired samples. RESULTS: The medial component gaps at 0° and 10° of flexion of post-posteromedial vertical capsulotomy were significantly greater, exceeding the minimal detectable change, than those pre posteromedial vertical capsulotomy (change of the gap after the procedure at 0° of flexion was 0.7 ± 0.7 mm and at 10° of flexion was 0.8 ± 0.8 mm; all P values < 0.05). The medial component gap mismatches between both 0° and 10°, and 45°, 90°, and maximum flexion were significantly smaller post posteromedial vertical capsulotomy than pre posteromedial vertical capsulotomy, with the values of the change exceeding the minimal detectable change (change of the gap mismatch after the procedure: knee flexion at 0° and 45° was - 0.6 ± 0.9 [mm], at 0° and 90° was 0.7 ± 1.0, at 0° and maximum flexion was - 0.6 ± 1.2, at 10° and 45° was - 0.7 ± 0.9, at 10° and 90° was - 0.8 ± 0.9, at 10° and maximum flexion was - 0.7 ± 1.1; all P values < 0.05). CONCLUSIONS: Posteromedial vertical capsulotomy increased the medial component gaps during knee extension but not during mid-flexion or full flexion during posterior-stabilized TKA. Posteromedial vertical capsulotomy improved mild medial component gap mismatch between extension and mid-flexion and full flexion during posterior-stabilized TKA. Surgeons can consider posteromedial vertical capsulotomy when there is intraoperative constriction of the medial component gap during extension in patients undergoing posterior-stabilized TKA.

Association between additional weekend rehabilitation and in-hospital mortality in patients with hip fractures.

Aims: The aim of this study was to investigate the association between additional rehabilitation at the weekend, and in-hospital mortality and complications in patients with hip fracture who underwent surgery. Methods: A retrospective cohort study was conducted in Japan using a nationwide multicentre database from April 2010 to March 2018, including 572,181 patients who had received hip fracture surgery. Propensity score matching was performed to compare patients who received additional weekend rehabilitation at the weekend in addition to rehabilitation on weekdays after the surgery (plus-weekends group), as well as those who did not receive additional rehabilitation at the weekend but did receive weekday rehabilitation (weekdays-only group). After the propensity score matching of 259,168 cases, in-hospital mortality as the primary outcome and systemic and surgical complications as the secondary outcomes were compared between the two groups. Results: The plus-weekends group was significantly associated with lower in-hospital mortality rates compared with the weekdays-only group (hazard ratio 0.86; 95% confidence interval 0.8 to 0.92; p < 0.001). Systemic complications such as acute coronary syndrome, heart failure, renal failure, and sepsis were significantly lower in the plus-weekends group, whereas urinary tract infection (UTI) and surgical complications such as surgical site infection and haematoma were significantly higher in the plus-weekends group. Conclusion: Additional weekend rehabilitation was significantly associated with lower in-hospital mortality, as well as acute coronary syndrome, heart failure, renal failure, and sepsis, but was also significantly associated with a higher risk of UTI and surgical complications. This result can facilitate the effective use of the limited rehabilitation resources at the weekend and improve the clinical awareness of specific complications. To establish more robust causal associations between additional rehabilitation over the weekend and clinical outcomes, further prospective studies or randomized controlled trials with larger sample sizes are warranted.

Reliability and validity of quantitative evaluation of anticipatory postural adjustments using smartphones.

[Purpose] This study aimed to investigate the reliability and validity of the quantitative evaluation of anticipatory postural adjustments using smartphones. [Participants and Methods] The study included 10 young control participants who underwent a one-legged stance with an accelerometer and a smartphone that were simultaneously attached to their lower back (L5). Acceleration was measured as the mediolateral component of the lumbar movement toward the stance side. The peak value of the time (peak latency) and the amount of displacement (peak magnitude) in the stance side direction of the lumbar acceleration were analyzed as anticipatory postural adjustment features. Intra-rater reliability was calculated for both accelerometer and smartphone measurements, while inter-rater reliability was calculated for smartphone measurements by two examiners. Validity was determined for both accelerometer and smartphone measurements. [Results] In this study, the intra-rater reliability of the peak latency and peak magnitude in accelerometer and smartphone measurements was confirmed, as was the inter-rater reliability in smartphone measurements. The intra-rater reliability was confirmed through re-testing, while the validity of the accelerometer and smartphone measurements was also confirmed. [Conclusion] The findings of this study suggest that the use of smartphones to measure anticipatory postural adjustments is highly reliable and valid, making it a useful clinical balance index. The method is simple and can be used for continuous patient monitoring.

Association of osteoporosis and high serum homocysteine levels with intraoperative periprosthetic fracture during total hip arthroplasty: a propensity-score matching analysis.

INTRODUCTION: Intraoperative periprosthetic fracture, one of the most frequent complications of total hip arthroplasty, is a very important factor that affects rehabilitation, hospitalization time, and cost of treatment. Osteoporosis is common in total hip arthroplasty patients and likely contributes to the increasing incidence of periprosthetic fracture. Despite this awareness, preoperative and postoperative osteoporosis evaluations remain insufficient. The purpose of this study was to evaluate the relationships between the occurrence of intraoperative periprosthetic fractures and both bone mineral density (BMD) and osteoporosis-related biomarkers. MATERIALS AND METHODS: This single-center retrospective study included a total of consecutive 487 hip joints of patients with a mean age of 65.5 ± 11.8 years who underwent total hip arthroplasty between July 2017 and December 2020. Patients with low BMD defined as T-score < -1.0 versus those with normal BMD were matched by a 1:1 propensity score to balance for patient baseline characteristics, and outcome was analyzed by a modified Poisson regression model. Our primary outcome was the incidence of intraoperative periprosthetic fracture during surgery. We also investigated the effect modification of osteoporosis-related biomarkers, including tartrate-resistant acid phosphatase 5b (TRACP-5b), total procollagen type 1 amino-terminal propeptide (total P1-NP), intact parathyroid hormone (intact PTH), and homocysteine, on osteoporosis and outcomes. RESULTS: After matching, 250 patients were analyzed. The risk of fracture was significantly higher in patients with low BMD than in normal BMD patients (Incidence rate ratio 5.00 [95% CI 1.11-22.43], p = 0.036). We also observed significant effect of high serum homocysteine on the occurrence of intraoperative fractures (Incidence rate ratio 8.38 × 106 [95% C; 3.44 × 106-2.01 × 107], p < 0.01). CONCLUSION: Preoperative osteoporosis and high serum homocysteine levels were risk factors for intraoperative periprosthetic fractures. LEVEL OF EVIDENCE: III, A single-center retrospective study.

Effect and feasibility of the combination of branched chain amino acid and exercise therapy on muscle mass and echo intensity of muscle in orthopedic patients in a convalescent rehabilitation hospital: A crossover trial.

Background and Aims: This study examined the feasibility of nutritional support combined with exercise intervention for restoring muscle and physical functions in convalescent orthopedic patients. Methods: We used a crossover design in which nutritional support combined with exercise intervention was administered daily during the early (1 month) and late (1 month) cycles with a 1-week washout period. The exercise intervention was performed twice daily for 2 months in the early and late groups. The exercise intervention consisted of one set of muscle strength, stretching, and physical activity exercises for 20 min each. Nutritional interventions were administered immediately after the exercise. A 3.4 g of branched-chain amino acid supplements (BCAAs) or 1.2 g of starch was ingested. We measured the skeletal muscle mass and isometric muscle strength of the limbs and performed balance tests. After the crossover, the BCAA and Placebo groups were compared. Results: The ratio of improvement in the echo intensity of the rectus femoris (RF) was significantly higher in the BCAA group. A comparison of the order of nutritional intervention showed a significant effect on the RF echo intensity in both groups only when BCAAs were administered. Conclusion: This study's results suggest that the proposed combined intervention improves muscle quality and mass in convalescent orthopedic patients.

Limited medial posterior capsular release increases the intraoperative medial component gap while maintaining the joint varus angle at extension in posterior-stabilized total knee arthroplasty.

PURPOSE: There is a lack of robust evidence for the magnitude of the effects of posterior capsular release (PCR) on intraoperative component gaps during total knee arthroplasty (TKA). The purpose of the present study was to quantify and compare the effects of partial versus full PCR on the intraoperative component gaps at various degrees of flexion during posterior-stabilized TKA. METHODS: Full PCR was performed on 39 consecutive cases (full PCR group), and partial PCR (the medial side up to and including the intercondylar notch) was performed on the subsequent 39 consecutive cases (partial PCR group) during posterior-stabilized TKA using the measured resection technique for varus knee osteoarthritis. Medial component gaps and varus angles at 0°, 10°, 45°, 90°, and a maximum of flexion were measured with a tensor device before and after the PCR. Differences between the two groups in post-release medial component gap increase and post-release joint varus angle increase were assessed using a t test. Pre- to post-release medial component gaps and joint varus angles in each group were compared using a paired samples t test. RESULTS: In both groups at 0° and 10° of flexion, post-release medial compartment gaps were significantly greater than pre-release gaps (all P < 0.001). At 45°, 90° and maximum flexion, the medial compartment gap increase did not exceed the minimal detectable change in either group. At 0° and 10° of flexion, there was no significant difference in post-release medial compartment gap change between the two groups. In the full PCR group, post-release joint varus angles at 0° of flexion were significantly greater than pre-release angles (P < 0.001), while there was no significant pre- and post-release difference in the partial PCR group. The change in post-release joint varus angles at 0° of flexion was significantly greater in the full PCR group than in the partial PCR group. CONCLUSION: Both full and partial PCR show similar clinical usefulness for increasing the medial component gap at extension and reducing component gap mismatch. A partial PCR can be used to avoid increasing joint varus angles at 0° of flexion. LEVEL OF EVIDENCE: Level 2 (prospective comparative study).

Preoperative Predictors of Instrumental Activities of Daily Living Disability in Older Adults 6 Months After Knee Arthroplasty.

OBJECTIVE: To investigate preoperative predictors of instrumental activities of daily living (IADL) disability in older adults 6 months after knee arthroplasty (KA). DESIGN: Prospective cohort study. SETTING: General hospital with an orthopedic surgery department. PARTICIPANTS: Two hundred twenty (N=220) patients 65 years or older with total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: IADL status was evaluated for 6 activities. Participants chose "able," "need help," or "unable" according to their capacity of executing these IADL. If they chose "need help" or "unable" for 1 or more items, they were defined as "disabled." Their usual gait speed (UGS), range of motion for the knee, isometric knee extension strength (IKES), pain status, depressive symptoms, pain catastrophizing, and self-efficacy were evaluated as predictors. Baseline and follow-up assessments were conducted 1 month before and 6 months after KA, respectively. Logistic regression analyses with IADL status as the dependent variable were performed at follow-up. All models were adjusted using age, sex, severity of the knee deformity, operation type (TKA or UKA), and preoperative IADL status as covariates. RESULTS: In total, 166 patients completed the follow-up assessment, and 83 (50.0%) reported IADL disability 6 months after KA. Preoperative UGS, IKES on the non-operated side, and self-efficacy were statistically significantly different between those with a disability at follow-up and those who did not and were therefore included in logistic regression models as independent variables. UGS (odds ratio, 3.22; 95% CI, 1.38-7.56; P=.007) was determined as a significant independent variable. CONCLUSIONS: The present study demonstrated the importance of evaluating preoperative gait speed to predict the presence of IADL disability in older adults 6 months after KA. Patients with poorer preoperative mobility should be provided careful postoperative care and treatment.

Psychological factors associated with instrumental activities of daily living disability in older adults with moderate to severe knee osteoarthritis.

BACKGROUND: The population of older adults with knee osteoarthritis (OA)-related disabilities is increasing globally. However, studies regarding instrumental activities of daily living (IADL) in older adults with knee OA are limited. OBJECTIVE: This study investigated the psychological factors associated with IADL disability in older adults with moderate to severe knee OA. METHODS: A cross-sectional study was conducted on 179 patients with knee OA aged ⩾ 65 years. The six-item short form of the Pain Catastrophizing Scale (PCS-6), the four-item short form of the Pain Self-Efficacy Questionnaire (PSEQ-4), and the fifteen-item Geriatric Depression Scale (GDS-15) were used to assess psychological factors. The participants were divided into IADL disabled and non-disabled groups. Binary logistic regression analyses were performed with the IADL disability status as the dependent variable. The PCS-6, PSEQ-4, and GDS-15 tools were included as independent variables in the logistic regression model. RESULTS: Of the 179 participants, 88 (49.1%) showed disability in conducting IADL. PSEQ-4 (odds ratio = 0.90, 95%; confidence interval = 0.82-0.99, p= 0.02) was a significant independent variable among all psychological factors. CONCLUSION: Even after controlling for cofounders, our study found that self-efficacy, assessed using the PSEQ-4, was related to IADL disability in older adults with moderate to severe knee OA.

A cross-sectional study evaluating patients' preferences for Salter innominate osteotomy.

BACKGROUND: Residual acetabular dysplasia in children after reduction of hip dislocation is often treated using Salter innominate osteotomy to prevent future osteoarthritis. Preventive surgery for asymptomatic patients, which could result in overtreatment, should be carefully applied with consideration of patients' opinions. In this study, we aimed to describe opinions on Salter innominate osteotomy as preventive surgery for children among adult patients who had undergone periacetabular osteotomy for hip pain due to hip dysplasia. METHODS: A mail-in questionnaire survey was conducted with 77 patients who underwent periacetabular osteotomy. Participants responded whether they would recommend Salter innominate osteotomy as preventive surgery for children and the reason for their opinion. We also performed a patient-based evaluation using the Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire and assessed clinical outcome measures with the Japanese Orthopedic Association score. Their recommendations and reasons were evaluated, and associations between their opinions and demographic and clinical characteristics were analyzed. RESULTS: Forty-three patients (56%) responded to the questionnaire. Of these, 10 (23%) patients recommended undergoing Salter innominate osteotomy, 28 (65%) patients did not, and 5 (12%) patients responded they were undecided. No significant association was observed between their opinions and demographic/clinical characteristics evaluated in the survey. The most frequent reason for why they do not recommend Salter innominate osteotomy was related to uncertainty about future hip pain. CONCLUSIONS: In total, 65% of the study participants did not recommend Salter innominate osteotomy for children with risk of dysplasia in the future. Participants' preferences regarding preventive surgery were not influenced by demographic and clinical characteristics.

Wear rate and osteolysis in two types of second-generation annealed highly cross-linked polyethylene in total hip arthroplasty: A retrospective comparative study with a minimum of five years.

BACKGROUND: As no previous study has directly compared the linear wear rate in two types of second-generation annealed highly cross-linked polyethylene, we performed a retrospective study with a minimum of 5-year follow-up to assess primary arthroplasties in the (1) wear rates and (2) incidence of osteolysis of the two types of HXLPE. HYPOTHESIS: There was no significant difference in the linear wear rate and the incidence of osteolysis between the two types of second-generation annealed highly cross-linked polyethylene. PATIENTS AND METHODS: In this single-center study, we reviewed 257 cases of primary cementless total hip arthroplasties between 2011 and 2015, which were performed with 32mm delta ceramic on second-generation annealed highly cross-linked polyethylene (X3 and E1 were used in 105 and 103 cases, respectively.). The mean wear rate was evaluated using a computer-assisted method, and the incidence of osteolysis was evaluated based on the appearance of a localized area with loss of trabecular bone or cortical erosion adjacent to the implants during the latest follow-up. RESULTS: In total, we evaluated 208 cases, followed postoperatively for over 5 years (mean, 6.1 years, range: 5.0-8.0). There were no significant differences between the two groups with respect to age (list in order of Group X, Group E, p value) (61.2±12.3, 62.7±12.1, p=0.36), sex (ratio of male: 17.1%, 14.6%, p=0.61), body mass index (22.9±3.7, 22.8±4.0, p=0.91), pre- (49.9±14.8, 48.5±13.8, p=0.49) and post-operative (91.3±9.1, 92.7±7.0, p=0.23) Japanese Orthopaedic Association Hip Score, cup size (50.8±3.0, 50.9±2.2, p=0.70), cup inclination (38.7±4.8, 37.6±4.8, p=0.10), and cup anteversion (18.7±6.9, 18.5±7.6, p=0.80). The mean linear wear rates of the X3 and E1 groups were 0.057±0.039 (range: 0-0.16) and 0.054±0.037mm/year (range: 0-0.15), respectively (p=0.61). No osteolysis was found on the final plain radiographs in both groups. DISCUSSION: This study revealed that both types of highly cross-linked polyethylene have excellent linear wear rates and were equally safe to use. However, the difference between the two materials in terms of the long-term wear rate should be further validated. LEVEL OF EVIDENCE: III; retrospective case control study.

Perioperative Complications of Laminoplasty in Degenerative Cervical Myelopathy -A Comparative Study Between Ossification of Posterior Longitudinal Ligament and Cervical Spondylotic Myelopathy Using a Nationwide Inpatient Database.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Laminoplasty (LAMP) is one of the effective methods to successfully achieve surgical decompression in patients with degenerative cervical myelopathy (DCM). However, little evidence exists regarding the perioperative complications in LAMP for patients with ossification of the longitudinal ligament (OPLL) compared with cervical spondylotic myelopathy (CSM). We aimed to investigate the perioperative complication rates and medical costs of DCM, including OPLL and CSM patients who underwent LAMP using a large national inpatient database. METHODS: This study identified patients who underwent LAMP for OPLL and CSM from 2010 to 2016 using the Japanese Diagnosis Procedure Combination database. We compared the incidence of perioperative complications (systemic and local), reoperation rates, medical costs during hospitalization, and mortality were between the OPLL and CSM groups after propensity score matching. RESULTS: This study included 22,714 patients (OPLL: 7485 patients, CSM: 15,229 patients). Consequently, 7169 pairs were matched. More perioperative systemic complications were detected in the OPLL group (one complication: 9.1% vs 7.7%; P = .002), especially for pneumonia (.5% vs .2%; P = .001) and dysphagia (.5% vs .2%; P = .004). The local complication rate was also higher in the OPLL group (paralysis: 1.1% vs .6%, P = .006; spinal fluid leakage: .4% vs .1%, P = .002). The hospitalization costs were approximately $2300 higher ($19,024 vs $16,770; P < .001) in the OPLL group. CONCLUSIONS: More perioperative complications and higher medical costs were noted in patients with OPLL than in patients with CSM who underwent LAMP.

The prevalence and treatment of osteoporosis in patients undergoing total hip arthroplasty and the levels of biochemical markers of bone turnover.

AIMS: Osteoporosis is common in total hip arthroplasty (THA) patients. It plays a substantial factor in the surgery's outcome, and previous studies have revealed that pharmacological treatment for osteoporosis influences implant survival rate. The purpose of this study was to examine the prevalence of and treatment rates for osteoporosis prior to THA, and to explore differences in osteoporosis-related biomarkers between patients treated and untreated for osteoporosis. METHODS: This single-centre retrospective study included 398 hip joints of patients who underwent THA. Using medical records, we examined preoperative bone mineral density measures of the hip and lumbar spine using dual energy X-ray absorptiometry (DXA) scans and the medications used to treat osteoporosis at the time of admission. We also assessed the following osteoporosis-related biomarkers: tartrate-resistant acid phosphatase 5b (TRACP-5b); total procollagen type 1 amino-terminal propeptide (total P1NP); intact parathyroid hormone; and homocysteine. RESULTS: The prevalence of DXA-proven hip osteoporosis (T-score ≤ -2.5) among THA patients was 8.8% (35 of 398). The spinal osteoporosis prevalence rate was 4.5% (18 of 398), and 244 patients (61.3%; 244 of 398) had osteopenia (-2.5 < T-score ≤ -1) or osteoporosis of either the hip or spine. The rate of pharmacological osteoporosis treatment was 22.1% (88 of 398). TRACP-5b was significantly lower in the osteoporosis-treated group than in the untreated group (p < 0.001). CONCLUSION: Osteoporosis is common in patients undergoing THA, but the diagnosis and treatment for osteoporosis were insufficient. The lower TRACP-5b levels in the osteoporosis-treated group - that is, osteoclast suppression - may contribute to the reduction of the postoperative revision rate after THA.Cite this article: Bone Joint Res 2022;11(12):873-880.

Effect of posterior capsular release on intraoperative joint gap mismatch in the mid-flexion range during posterior-stabilized total knee arthroplasty.

INTRODUCTION: Intraoperative mismatch between extension and mid-flexion joint gaps remains a critical issue in posterior-stabilized total knee arthroplasty (PS-TKA). Posterior capsular release has been found to increase the extension joint gap. However, there is still a lack of robust evidence for the effect of posterior capsular release on the mid-flexion joint gap. The purpose of the present study was to quantify the effect of posterior capsular release on the intraoperative joint gap from extension through 45° mid-flexion to flexion and to clarify how this procedure might affect the improvement of gap mismatch in the mid-flexion 45° range. MATERIALS AND METHODS: In total, 38 consecutive cases of primary PS-TKA were reviewed. The center, medial, and lateral component gaps from extension to flexion were measured with a tensor device before and after posterior capsular release. The minimal detectable change for joint gap measurement was calculated using two methods, error variance and intra-observer intraclass correlation coefficients. Pre- and post-release joint gap differences were assessed using the paired t-test. RESULTS: Minimal detectable change was found to be 0.59 mm. At 0° and 10° of flexion, the post-release center, medial, and lateral component gaps were significantly greater than at pre-release. At 45° and 90° and maximum flexion, there were no joint gap differences exceeding the minimal detectable change. The joint gap mismatches between 0° and 10°, and 45°, 90° and maximum flexion were significantly smaller at post-release than those at pre-release with the change values exceeding the minimal detectable change (P < 0.05). CONCLUSION: Posterior capsular release significantly decreased both joint gap mismatch between extension and 45° mid-flexion, and extension and flexion, showing clinical usefulness in PS-TKA.

New quantitative evaluation of anticipatory postural adjustments using a smartphone in patients with Parkinson's disease.

OBJECTIVE: To investigate a smartphone-enabled quantitative evaluation of anticipatory postural adjustments (APA) during one-leg stance (OLS) movements among individuals with Parkinson's disease (PD). METHODS: This cross-sectional study included 10 young controls, 10 older individuals, and 13 individuals with PD. A smartphone and accelerometer were attached to the participants' lower back (L5), and the movements of the lower back toward the stance side during OLS were measured. For acceleration, the time to the peak value in the stance direction (peak latency [PL]) and the amount of displacement to the peak value in the stance direction (peak magnitude [PM]) were analyzed as APA characteristics. Additionally, the measured PL was divided by the PM for each group to obtain the APA ratio (APAr) as a new index. RESULTS: Individuals with PD showed a delayed PL and decreased PM (vs. young controls: p = .002 for PL, p < .001 for PM) (vs. older individuals: p = .022 for PL, p = .001 for PM). The APAr clustered the young controls, older individuals, and individuals with PD. According to the receiver operating characteristic curve the APAr value was 0.95, and individuals in the PD group were identified (i.e. area under the curve: 0.98; sensitivity: 85.0%; specificity: 100%). Moreover the APAr was correlated with severity and balance ability in individuals with PD (p = .015 for NFOG-Q, p = .028 for UPDRS, p = .036 for TUG, p = .015 for Mini-BESTest, p = .018 for OLS time). CONCLUSIONS: This smartphone-based evaluation using the APAr index was reflective of disease severity and decreased balance ability among individuals with PD. The facilitation of this measurement can help clinicians and physiotherapists quantitatively evaluate the APA of individuals with PD at laboratories and hospitals as well as in home environments.

Medial osteophyte resection width correlates with correction of the medio-lateral component gap imbalance during posterior-stabilized total knee arthroplasty.

BACKGROUND: There is a lack of robust evidence for a correlation between the medial osteophyte resection and correction of the medio-lateral gap imbalance during total knee arthroplasty. The purpose of the present study was to quantify the effect of osteophyte resection on the medio-lateral component gap imbalance during posterior-stabilized total knee arthroplasty. METHODS: Forty-five cases of primary posterior-stabilized total knee arthroplasty using the measured resection technique with posterior-stabilized prosthesis for varus knee osteoarthritis were reviewed. Medial and lateral joint gaps at 0°, 10°, 45°, and 90° of flexion, and maximum flexion were measured intraoperatively before and after the osteophyte resection. The relationship between medial osteophyte resection width and change of joint varus angle and medial component gap were assessed using Pearson's correlation coefficient. FINDINGS: Medial component gap and joint varus angle values at post medial osteophyte resection were significantly larger and lower than at pre-resection (Medial gap: pre 9.5 ± 1.8 mm, post 10.3 ± 1.8 mm, P < 0.001, Joint angle: pre 5.2 ± 2.9°, post 4.2 ± 2.9°, P < 0.001). There was no significant difference between pre and post medial osteophyte resection in lateral component gaps. Per each 1 mm of medial osteophyte resection width, increases of 0.13 mm medial component gap and 0.2° valgus were observed (Medial gap: r = 0.38, P < 0.001, Joint angle: r = 0.38, P < 0.001). INTERPRETATION: Medial osteophyte resection increases the medial component gap without lateral component gap increase, while decreasing the joint varus angle in primary posterior-stabilized total knee arthroplasty for varus knee osteoarthritis. Osteophyte resection width was found to correlate with correction of the medio-lateral component gap imbalance.