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.

Snapping Knee Syndrome of the Sartorius Accompanying Osteoarthritis Cured by Osteophyte Removal During Total Knee Arthroplasty.

Snapping knee syndrome on the medial side is rare. Here, we report the case of a patient with snapping knee syndrome of the sartorius with knee osteoarthritis. A large osteophyte at the posteromedial femoral condyle impinged on the sartorius myotendinous junction, causing painless snapping. The patient was successfully treated with osteophyte removal and total knee arthroplasty while preserving the tendon. Hence, tendon release or resection to treat snapping syndrome is not always necessary if the underlying cause can be eliminated. Furthermore, we found that while tendon tension is important for the occurrence of snapping syndrome, the impingement site determines the occurrence of snapping pain.

Japanese Orthopaedic Association 2019 Guidelines for osteonecrosis of the femoral head.

PURPOSE: The Clinical Practice Guidelines for Osteonecrosis of the Femoral Head (ONFH) 2019 Edition, written by the working group for ONFH guidelines of the Japanese Investigation Committee (JIC) for ONFH under the auspices of the Japanese Ministry of Health, Labour, and Welfare and endorsed by the Japanese Orthopaedic Association, were published in Japanese in October 2019. The objective of this guideline is to provide a support tool for decision-making between doctors and patients. METHODS: Procedures for developing this guideline were based on the Medical Information Network Distribution Service Handbook for Clinical Practice Guideline Development 2014, which proposed an appropriate method for preparing clinical guidelines in Japan. RESULTS: This clinical practice guideline consists of 7 chapters: epidemiology; pathology; diagnosis; conservative therapy; surgical treatment: bone transplantation/cell therapy; surgical treatment: osteotomy; and surgical treatment: hip replacement. Twelve background questions and 13 clinical questions were determined to define the basic features of the disease and to be addressed when deciding treatment in daily practice, respectively. CONCLUSIONS: The clinical practice guidelines for the ONFH 2019 edition will be useful for physicians, investigators, and medical staff in clinical practice, as well as for patients, during the decision-making process when defining how to treat ONFH.

Histological Analysis of Cartilage Defects Repaired with an Autologous Human Stem Cell Construct 48 Weeks Postimplantation Reveals Structural Details Not Detected by T2-Mapping MRI.

OBJECTIVE: The aim of this study was to elucidate the efficacy of T2-mapping MRI and correlation with histology for the evaluation of tissue repair quality following the first-in-human implantation of an autologous tissue engineered construct. DESIGN: We directly compared the results of T2-mapping MRI of cartilage repair tissue with the histology of a biopsy specimen from the corresponding area at 48 weeks postoperatively in 5 patients who underwent the implantation of a scaffold-free tissue-engineered construct generated from autologous synovial mesenchymal stem cells to repair an isolated cartilage lesion. T2 values and histological scores were compared at each of 2 layers of equally divided halves of the repair tissue (upper and lower zones). RESULTS: Histology showed that the repair tissue in the upper zone was dominated by fibrous tissue and the ratio of hyaline-like matrix increased with the depth of the repair tissue. There were significant differences between upper and lower zones in histological scores. Conversely, there were no detectable statistically significant differences in T2 value detected among zones of the repair tissue, but zonal differences were detected in corresponding healthy cartilage. Accordingly, there were no correlations detected between histological scores and T2 values for each repair cartilage zone. CONCLUSION: Discrepancies in the findings between T2 mapping and histology suggest that T2 mapping was limited in ability to detect details in the architecture and composition of the repair cartilage.

Real-time determination and visualization of two independent quantities during a manufacturing process of pharmaceutical tablets by near-infrared hyperspectral imaging combined with multivariate analysis.

During pharmaceutical manufacturing, line-scan hyperspectral imaging enables us to collect several electromagnetic spectra at each pixel in a two-dimensional plane for each tablet. The present study quantitatively determines two independent values of the active pharmaceutical ingredient (API) content in a tablet and the amount of coating on a surface of the same tablet simultaneously; the process is visualized by means of a near-infrared hyperspectral imaging (NIR-HSI) system combined with multivariate data analysis at a typical manufacturing speed of 4,000 tablets per minute. The API content and the amount of coating were controlled to be in the range 80-120% and 0-7 mg, respectively. The results of the cross validation of regression models demonstrated a coefficient of determination (R2) of 0.942, a root-mean-square error of cross validation (RMSECV) of 3.48% for the API content, an R2 of 0.939, and an RMSECV of 0.46 mg for the amount of coating. These results demonstrated that the API content in a tablet as well as the amount of coating on the surface of the same tablet can be simultaneously determined with sufficient accuracy. This technique is practically applicable to process analytical technology in pharmaceutical manufacturing.

Spinal Injuries in Suicidal Jumpers.

STUDY DESIGN: This was a retrospective case series at a single institution. OBJECTIVE: The study was performed to investigate the characteristics of spinal injuries in survivors of suicidal jumping. SUMMARY OF BACKGROUND DATA: Spinal fracture/dislocation is associated with high-energy trauma such as that induced by motor vehicle accidents. Survivors of suicidal jumping sometimes sustain spinal injuries. However, the characteristics of such spinal injuries are unclear. METHODS: We identified 87 survivors of suicidal jumping who sustained spinal injuries from 2007 to 2016 in our institution. We compared the demographic data, radiological findings, neurological status, associated injuries, treatments, and mental health conditions between these 87 survivors and 204 non-suicidal patients with spinal injury. RESULTS: Suicidal jumpers were predominantly female (67%) and 10 years younger than non-suicidal patients. Mental health problems, mainly schizophrenia and depression, were diagnosed in 77% of suicidal jumpers. Neurological damage from spinal trauma was generally less severe in suicidal jumpers than in non-suicidal patients. Most spinal injuries in suicidal jumpers were located in the thoracic or lumbar spine region (85%). Among comorbid injuries, extremity injuries were highly associated with spine injury in suicidal jumpers. Nearly 70% of suicidal jumpers exhibited extremity injury in contrast to 33% of non-suicidal patients. Approximately, 25% of suicidal jumpers underwent surgical treatment. Surgical treatment was similarly performed on suicidal jumpers and non-suicidal patients regardless of the discrepancy in neurological damage between these two groups. CONCLUSION: Spinal injuries in suicidal jumpers differed from spinal injuries in non-suicidal patients with regard to sex, age, mental health condition, injury location, neurologic damage, and associated injuries. Most survivors of suicidal jumping were young female patients with mental health problems. They tended to have thoracic and lumbar spine trauma rather than cervical trauma with less severe neurological deficits and a higher incidence of accompanying limb injury. LEVEL OF EVIDENCE: 3.

First-in-Human Pilot Study of Implantation of a Scaffold-Free Tissue-Engineered Construct Generated From Autologous Synovial Mesenchymal Stem Cells for Repair of Knee Chondral Lesions.

BACKGROUND: Articular cartilage has limited healing capacity, owing in part to poor vascularity and innervation. Once injured, it cannot be repaired, typically leading to high risk for developing osteoarthritis. Thus, cell-based and/or tissue-engineered approaches have been investigated; however, no approach has yet achieved safety and regenerative repair capacity via a simple implantation procedure. PURPOSE: To assess the safety and efficacy of using a scaffold-free tissue-engineered construct (TEC) derived from autologous synovial membrane mesenchymal stem cells (MSCs) for effective cartilage repair. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Five patients with symptomatic knee chondral lesions (1.5-3.0 cm2) on the medial femoral condyle, lateral femoral condyle, or femoral groove were included. Synovial MSCs were isolated from arthroscopic biopsy specimens and cultured to develop a TEC that matched the lesion size. The TECs were then implanted into chondral defects without fixation and assessed up to 24 months postoperatively. The primary outcome was the safety of the procedure. Secondary outcomes were self-assessed clinical scores, arthroscopy, tissue biopsy, and magnetic resonance image-based estimation of morphologic and compositional quality of the repair tissue. RESULTS: No adverse events were recorded, and self-assessed clinical scores for pain, symptoms, activities of daily living, sports activity, and quality of life were significantly improved at 24 months after surgery. Secure defect filling was confirmed by second-look arthroscopy and magnetic resonance imaging in all cases. Histology of biopsy specimens indicated repair tissue approaching the composition and structure of hyaline cartilage. CONCLUSION: Autologous scaffold-free TEC derived from synovial MSCs may be used for regenerative cartilage repair via a sutureless and simple implantation procedure. Registration: 000008266 (UMIN Clinical Trials Registry number).

Exercise Therapy Interventions in Patients With Hip Osteoarthritis: Comparison of the Effects of DVD and Website-Based Interventions.

BACKGROUND: Prevalence of developmental hip dysplasia is high in Japan. Exercise therapy has been proven effective to treat certain aspects of hip osteoarthritis. Moreover, therapy provided via digital video discs (DVDs) and websites allows patients to exercise in the comfort of their own homes. However, no studies have evaluated the effectiveness of visual instructions in patients with hip disorders. OBJECTIVE: This study aimed to compare the effectiveness of exercise therapy administered via DVD and that administered via a website. METHODS: We developed a six-step progressive exercise therapy program for patients with hip osteoarthritis, which included three kinds each of open kinetic chain and closed kinetic chain exercises. Once the program was developed, exercise DVDs were produced. In addition to the six-step exercise program, our website was enabled to count the number of exercises performed by each patient and was accessible via the Internet at any time. Patients with hip osteoarthritis for whom surgery was not advised were enrolled by one university hospital in the Kansai area in Japan. Clinical symptoms and hip function were quantified using the Japanese Orthopedic Association Hip Disease Evaluation Questionnaire (JHEQ) and the Oxford Hip Score (OHS). Quality of life was measured using the SF-8 Health Survey, and self-efficacy for continued exercise was measured using the General Self-Efficacy Scale (GSES). Questionnaires were completed preintervention and after 6 months. RESULTS: At 6-month follow-up, 10 DVD users (1 male, 9 female; mean age 51.3, SD 16.1 years) and 18 website users (2 male, 16 female; mean age 52.4, SD 10.4 years) were reachable. The change in each parameter could not be confirmed a significant improvement. However, most items tended to reflect overall improvement during the 6 months of intervention (P=.05-.94; paired t test). Regarding effect size, we considered a small effect to be greater than 0.2. Little effect was observed for JHEQ pain, SF-8 physical component summary (PCS), and SF-8 mental component summary in the DVD group, as well as OHS, SF-8 (PCS), and GSES in the website group. CONCLUSIONS: When comparing the effectiveness of exercise therapy between our DVD and website, we found that although both groups tended to improve in physical function, only the website group showed tendency of enhanced self-efficacy.

Noninvasive, high-speed, near-infrared imaging of the biomolecular distribution and molecular mechanism of embryonic development in fertilized fish eggs.

In this study, the distribution of biomaterials and its molecular mechanism of embryonic development in Japanese medaka fish were analyzed nondestructively and noninvasively without staining using near-infrared (NIR) imaging. The microscopic NIR imaging system used in this research was a device capable of ultra-high-speed imaging; using this system, one can acquire microscopic imaging data in a few seconds. Therefore, the medaka eggs remained alive throughout measurements and were successfully monitored in vivo. The distributions of biomolecules were examined by mapping the intensities of NIR bands resulting from lipids, proteins and water in 2 dimensions (2D). The structures of eyes, lipid bilayer membranes, micelles and water-structure differences at the interface of different substances constituting different structures on the egg were visualized. Furthermore, insights on the metabolic mechanisms of lipids and membrane functions were drawn from the biased distribution of lipoproteins and the presence of unsaturated fatty acids in the egg membrane. These results indicated the potential for NIR imaging in evaluating the biological functions and metabolic systems of cells and embryos.

Characteristics of bone turnover markers in rapidly destructive coxopathy.

The purpose of this study was to clarify bone turnover marker levels in rapidly destructive coxopathy (RDC). Twenty patients with RDC (mean age, 72 ± 11 years; 3 men, 17 postmenopausal women), 111 with osteoarthritis (OA) (age, 60 ± 10 years; 15 men, 13 premenopausal women, 83 postmenopausal women), and 18 with osteonecrosis of femoral head (ON) (55 ± 14 years; 11 men, 3 premenopausal women, 4 postmenopausal women), and 100 patients with femoral neck fracture (FNF) (81 ± 10 years; 27 men, 73 postmenopausal women) were included. Serum tartrate-resistant acid phosphatase 5b (TRACP-5b), bone alkaline phosphatase (BAP), matrix metalloproteinase-3 (MMP-3) levels, and bone mineral density (BMD) of proximal femur and lumbar spine were investigated. TRACP-5b levels were significantly higher in RDC than in OA and ON, whereas BAP levels were higher in RDC than in OA (P < 0.05). MMP-3 levels were higher in RDC and ON than in OA (P < 0.05). TRACP-5b were higher in RDC than OA (P < 0.05) and FNF (P < 0.05) in performing propensity score matching; there were no differences in BMD between RDC and OA. TRACP-5b showed the largest area under the curve (AUC, 0.82) according to receiver operating characteristic (ROC) curve analysis for diagnosing RDC against OA and ON. AUCs of BAP and MMP-3 were 0.78 and 0.74. The respective sensitivities and specificities were 70.0 % and 85.3 % for TRACP-5b (cutoff, 623 mU/dl), 95.0 % and 57.1 % for BAP (13.8 U/l), and 70.0 % and 76.4 % for MMP-3 (52.7 ng/ml). The lack of differences in BMD suggested that high bone turnover marker levels may reflect osteoclast cell activation in RDC hips. Serum TRACP-5b and BAP could be RDC markers.

Comparison of rotational acetabular osteotomy performed with navigation by surgeons with different levels of experience of osteotomies.

PURPOSE: Rotational acetabular osteotomy (RAO) is used to treat developmental hip dysplasia (DDH). It requires detailed anatomical knowledge of the pelvic anatomy and three-dimensional cognitive skills. We addressed whether a computer navigation system combined with a preoperative computed tomography-based plan enabled surgeons to perform RAO safely and reliably through a mini-incision regardless of their level of experience with performing osteotomies. METHODS: We enrolled 24 patients (25 hips) with DDH (radiographic grade 0 or 1 osteoarthritic changes: Tönnis classification). Using the navigation system, four surgeons performed RAO via a mini-incision transtrochanteric approach. Two experienced surgeons treated 15 patients (16 hips). Two surgeons with low-level RAO experience treated nine patients (9 hips). Operative data and clinical and radiographic outcomes were compared. Average follow-up was 3.2 years. RESULTS: There were no significant differences in the (1) incision length, operation time, or intraoperative blood loss; (2) numerical pain rating scale score and Western Ontario and McMaster Universities Osteoarthritis Index Scale score at 1, 2 years, and at the latest follow-up; (3) preoperative and postoperative acetabular coverage of the femoral head, postoperative joint congruency, postoperative medial and distal femoral head displacement, or acetabular thickness; and (4) positional accuracy of iliac, pubic, and ischial osteotomy and accuracy of acetabular coverage of the femoral head. CONCLUSIONS: Clinical and radiographic outcomes of RAO with navigation were not influenced by the surgeons' level of osteotomy experience.

Postoperative Limb-Offset Discrepancy Notably Affects Soft-Tissue Tension in Total Hip Arthroplasty.

BACKGROUND: Inadequate soft-tissue tension in total hip arthroplasty is regarded as one cause of dislocation or abductor muscle weakness. The purpose of the present study was to assess how the postoperative discrepancy in limb offset (consisting of both femoral offset and acetabular offset) affects soft-tissue tension compared with other factors among patients with unilateral hip disease undergoing total hip arthroplasty. METHODS: A total of 89 consecutive patients underwent mini-incision total hip arthroplasty involving an anterolateral or posterior approach and with use of a computer navigation system. Soft-tissue tension was measured by applying traction amounting to 40% of body weight with the joint positioned at 0°, 15°, 30°, and 45° of flexion. The separation between the cup and the prosthetic head was measured using the navigation system. RESULTS: The cup-head separation differed significantly for varying angles of flexion (p < 0.001), with the greatest distance noted at 15° of flexion (mean and standard deviation, 11 ± 5 mm). Stepwise multiple regression analysis showed that postoperative limb-offset discrepancy, an anterolateral approach, and preoperative abduction range of motion were correlated with the cup-head separation at 15° of flexion. Postoperative limb-offset discrepancy was negatively correlated with the cup-head separation at 0°, 15°, and 30° of flexion. CONCLUSIONS: Postoperative limb-offset discrepancy significantly affected the soft-tissue tension in total hip arthroplasty at varying degrees of flexion. This indicated that it is important to restore normal limb offset without overlengthening to obtain adequate soft-tissue tension in total hip arthroplasty. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Hip range-of-motion (ROM) is less than normal after rotational acetabular osteotomy for developmental dysplasia of the hip: A simulated ROM analysis.

The optimal reorientation of the acetabulum for developmental dysplasia of the hip (DDH) is unknown in terms of hip range-of-motion (ROM). The simulated ROMs of 52 DDHs after rotational acetabular osteotomy (RAO) with several patterns of femoral head coverage and those of 73 normal hips were analyzed using computer models reconstructed from CT images. After RAO with a lateral center edge angle (LCEA) of 30° and an anterior center edge angle (ACEA) of 55° producing coverage similar to that of normal hips, the maximal flexion and maximal internal rotation at 110° flexion with 20° adduction were significantly smaller than those of the normal group. To achieve ROMs after RAO similar to those of the normal group, an LCEA of 30° with an ACEA of 45°, an LCEA of 25° with an ACEA of 45° to 50°, and an LCEA of 20° with an ACEA of 50° could be preferred angles to target, even though they provided smaller coverage than that of normal hips. After RAO producing femoral head coverage similar to that of normal hips, the maximal flexion and the maximal internal rotation at 110° flexion with 20° adduction were significantly smaller than those of the normal group.

The Validity of Using the Posterior Condylar Line as a Rotational Reference for the Femur.

Rotation of the femur is usually measured by the posterior condylar line (PCL). However, the functional position of the PCL has not been studied well. The angles between the PCL and the horizontal body line (HBL) were measured on preoperative computed tomographic (CT) images of 324 hips with osteoarthritis and compared with the CT images taken after hip arthroplasty. The PCL rotated 0.4° (±10.9° SD) internally from the HBL on preoperative CT images and was significantly correlated with femoral anteversion, Kellgren-Lawrence grade, and sex. On postoperative CT images, the PCL rotated 10.1° (interquartile range, 1.7°-15.5°) internally from the HBL. There was individual variance in the position of the PCL, and caution may be needed when using it as a rotational reference.

Shape-based acetabular cartilage segmentation: application to CT and MRI datasets.

PURPOSE: A new method for acetabular cartilage segmentation in both computed tomography (CT) arthrography and magnetic resonance imaging (MRI) datasets with leg tension is developed and tested. METHODS: The new segmentation method is based on the combination of shape and intensity information. Shape information is acquired according to the predictable nonlinear relationship between the U-shaped acetabulum region and acetabular cartilage. Intensity information is obtained from the acetabular cartilage region automatically to complete the segmentation procedures. This method is evaluated using 54 CT arthrography datasets with two different radiation doses and 20 MRI datasets. Additionally, the performance of this method in identifying acetabular cartilage is compared with four other acetabular cartilage segmentation methods. RESULTS: This method performed better than the comparison methods. Indeed, this method maintained good accuracy level for 74 datasets independent of the cartilage modality and with minimum user interaction in the bone segmentation procedures. In addition, this method was efficient in noisy conditions and in detection of the damaged cartilages with zero thickness, which confirmed its potential clinical usefulness. CONCLUSIONS: Our new method proposes acetabular cartilage segmentation in three different datasets based on the combination of the shape and intensity information. This method executes well in situations where there are clear boundaries between the acetabular and femoral cartilages. However, the acetabular cartilage and pelvic bone information should be obtained from one dataset such as CT arthrography or MRI datasets with leg traction.