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.

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.

Thrombophylaxis with low-dose, short-term fondaparinux after elective hip surgery.

Some studies have cautioned about the possibility of bleeding complications with routine use of anticoagulants like fondaparinux (FPX) for thrombophylaxis after elective hip surgery. Overdosing or prolonged periods of anticoagulant use should be avoided. We trialed a new regimen using FPX and tranexamic acid (TA) to reduce the risk of bleeding complications while maintaining efficacy in preventing deep vein thrombosis (DVT). The present study evaluated the effectiveness and safety of this regimen in 391 consecutive patients. Each patient was assigned either the FPX group, administered a once-daily subcutaneous injection of 1.5 mg of FPX on postoperative days 2, 3, and 4; or the intermittent pneumatic compression (IPC) group, which used an IPC device continuously for 1-2 days with no administration of any anticoagulant drugs. Ultrasonography was performed to diagnose DVT in all patients. No cases of fatal or symptomatic pulmonary embolism were encountered in either group, but six patients (3.1 %) in the FPX group and nine patients (6.0 %) in the IPC group showed asymptomatic distal DVT. The incidence of DVT tended to be lower (p = 0.19), volumes of intraoperative (p < 0.01) and postoperative (p < 0.01) blood loss were significantly smaller, and hemoglobin level was significantly higher in the FPX group than in the IPC group (p < 0.01). Our new thrombophylactic regimen using FPX and TA appears effective and safe for use after elective hip surgery.

Volume Increases of the Gluteus Maximus, Gluteus Medius, and Thigh Muscles After Hip Arthroplasty.

BACKGROUND: Muscle atrophy in osteoarthritis (OA) patients is expected to recover after total hip arthroplasty (THA) because of the increase in activity levels. Although some reports have shown an increase in the thigh muscles (Th) after THA, no reports of increases in the gluteal muscles and of analyses of the factors related to muscle recovery have been published. In this study, the changes in the gluteal and Th volumes after THA were quantitatively evaluated using computed tomography (CT) images, and the factors related to muscle recovery were analyzed. METHODS: The subjects were 40 OA hips with CT images taken 3 weeks after THA (first postoperative [postop] CT) and more than 2 years after THA (second postop CT). The cross-sectional areas of gluteus maximus (G-max), gluteus medius (G-med), and Th were measured in both CT images. The factors related to muscle recovery that were measured and evaluated were age, gender, days from operation, surgical approach, Kellgren-Lawrence grades, and hip functional score (Japanese Orthopaedics Association hip score). RESULTS: All measured cross-sectional areas of the operated side increased significantly from the first postop CT to the second postop CT (G-max, 40%; G-med, 11%; and Th, 20%). In the analysis of the factors related to muscle recovery, the increase rate of G-max correlated significantly with patient age, and the increase rate of G-med correlated significantly with the increase in Japanese Orthopaedics Association hip score. CONCLUSIONS: Hip OA can lead to atrophy of the gluteal and Th, but the muscle volume can recover more than 2 years after THA.

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.

Fluctuation of Cup Orientation During Press-Fit Insertion: A Possible Cause of Malpositioning.

We evaluated real-time angular changes during press-fit cup insertion in 70 total hip arthroplasties. Inclination and anteversion cup angles on navigation system were recorded after each procedure of five hammer blows during cup insertion, and maximum deviated inclination (MDI) and anteversion (MDA) angles until the cup was fully seated were measured. We found 1 (1%) and 29 (41%) hips with increases and decreases in MDI of 5° or more, and 13 (19%) and 6 (8%) hips with increases and decreases in MDA of 5° or more, respectively. The MDI in men was significantly lower and the MDA for left-side surgery was significantly higher. Surgeons should pay attention to fluctuation in angular changes during cup insertion and may consider countermeasures to minimize cup malpositioning.

Difference in Stem Alignment Between the Direct Anterior Approach and the Posterolateral Approach in Total Hip Arthroplasty.

The purpose of this study was to investigate the effects of different surgical approaches, the posterolateral approach (PLA) and the direct anterior approach (DAA), on postoperative femoral anteversion and stem coronal and sagittal alignment in total hip arthroplasty (THA), and to identify the factors related to postoperative femoral anteversion and stem alignment. A total of 209 hips of 181 patients were evaluated. THA was performed through the PLA in 80 hips and through the DAA in 129 hips. Femoral anteversion and stem alignment were measured on postoperative computed tomography images. The factor related to postoperative anteversion change was preoperative femoral anteversion, and the surgical approaches did not affect the postoperative anteversion change, while surgical approach did have an effect on stem sagittal alignment.

Synovial joint fluid cytokine levels in hip disease.

OBJECTIVE: The purpose of this study was to evaluate cytokine level characteristics in the hip joint fluid, including rapidly destructive coxopathy (RDC), OA, osteonecrosis (ON) of the femoral head and RA. METHODS: Thirty-three hips with RDC, 57 with OA, 36 with ON and 10 with RA were included in the study. OA hips were divided into two groups: 20 hips with early OA without joint space narrowing and 37 hips with terminal OA. ON hips were divided into three groups: 13 hips with <3 mm collapse, 14 hips with >3 mm collapse and 9 hips with terminal ON. Joint fluid was collected during surgery. Cytokine levels including IL-1ß, IL-6, IL-8 and TNF-α were measured using homogeneous time-resolved fluorescence. RESULTS: All measured cytokine levels in RDC were significantly higher than those in OA (P < 0.05). Terminal OA showed higher cytokine levels than those in early OA (P < 0.05). IL-6 and TNF-α levels in the ON group with >3 mm collapse were higher than those found in the ON group with <3 mm collapse. In comparing cytokine levels between RDC, terminal OA, RA and terminal ON, RDC showed significantly higher IL-8 levels than terminal OA and RA (P < 0.05). CONCLUSION: IL-8 levels in RDC were higher than in the other hip diseases. The IL-8 level may reflect the aggressiveness of joint destruction in RDC, and IL-6 and TNF-α levels may also reflect ongoing destruction in OA and ON.

Is ultrasound screening reliable for adverse local tissue reaction after hip arthroplasty?

There is increasing awareness of prevalence of adverse local tissue reaction (ALTR) surrounding metal-on-metal (MoM) and highly cross-linked polyethylene (HXLPE) bearings, and sensitive and simple screening modalities for ALTR are required. We examined reliability of ultrasound screening for ALTR in 131 hips of 105 patients who received both ultrasound and MRI examinations after hip arthroplasty with MoM or HXLPE bearings. Using the MRI results as reference, sensitivity, specificity and accuracy of ultrasound were 74%, 92% and 84% around MoM bearings, and 90%, 83%, and 85% around HXLPE bearings. Ultrasound detected ALTR in 11 hips that were not shown with MRI. Ultrasound examination is assumed to be a reliable screening tool for detecting clinically important ALTR lesions developing in the anterior region around MoM or HXLPE bearings.

Spinal factors influencing change in pelvic sagittal inclination from supine position to standing position in patients before total hip arthroplasty.

In some atypical patients, pelvic sagittal inclination (PSI) changes posteriorly by >10° from supine to standing position before total hip arthroplasty (THA). Several studies have suggested PSI in standing position is related to lumbar degeneration. The purpose of this study was to investigate spinal factors influencing changes in PSI from supine to standing position before THA. Participants comprised 163 consecutive patients who had undergone THA. Presence of compression fractures, presence of lumbar spondylolisthesis, thoracic kyphosis angle, lumbar lordosis angle, S1 anterior tilt angle and T4 plumb line position were investigated as spinal factors. Presence of compression fractures, age, presence of lumbar spondylolisthesis and small S1 anterior tilt angle were independently associated with posterior change in PSI from supine to standing position in patients before THA.

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.

Does the extent of osteonecrosis affect the survival of hip resurfacing?

BACKGROUND: The effect of the extent of osteonecrosis on the survival of hip resurfacing for osteonecrosis of the femoral head (ONFH) has not been well documented, but is a potentially important variable in the decision to perform resurfacing. QUESTIONS/PURPOSES: We examined (1) the relationship between the volume of osteonecrosis in the femoral head before surgery and the extent of the residual necrotic bone after femoral head machining, (2) how the extent of the residual necrotic bone relative to the resurfaced femoral head (after femoral head machining) affected the survival of total hip resurfacing for patients with ONFH, and (3) how the extent of the necrotic bone relative to the entire femoral head (before femoral head machining) affected the survival and clinical outcome scores of patients who underwent total hip resurfacing. METHODS: Thirty-three patients (39 hips) who underwent hip resurfacing were reviewed after a mean followup of 8 years. The extent of osteonecrosis in the femoral head and residual osteonecrosis in the implant bony bed after femoral head machining were estimated using a three-dimensional MRI-based templating system. RESULTS: There was a statistically significant difference in the extent of osteonecrosis before and after femoral head machining, although the two were well correlated (r = 0.97). The mean percentage of osteonecrosis in the implant bony bed after femoral head machining was 5% smaller than that relative to the entire femoral head (range, -9% to 15%). There were no significant differences in implant survival between groups with small and large osteonecrosis classified by either the total amount of osteonecrosis before surgery or residual osteonecrosis after femoral head machining. CONCLUSION: The extent of osteonecrosis in the femoral head significantly decreased after femoral head machining. Neither the residual osteonecrosis volume in the implant bony bed after femoral head machining nor the total amount of osteonecrosis before femoral head machining had significant influence on the survival of hip resurfacing.

Three-dimensional topographical variation of femoral cartilage T2 in healthy volunteer knees.

OBJECTIVE: Quantitative knee cartilage T2 assessment on limited two-dimensional midsagittal or midcoronal planes may be insufficient to assess variations in normal cartilage composition. The purpose of this work was to reveal characteristic 3D distribution of T2 values in femoral cartilage in healthy volunteer knees. MATERIALS AND METHODS: Sixteen volunteers were enrolled in this study. One knee joint in each volunteer was imaged using a 3D fast image employing steady-state acquisition cycled phases (FIESTA-C) sequence for modeling distal femoral morphology, as well as a sagittal T2 mapping of cartilage. 3D distribution of cartilage T2 values was generated for the femoral condyles. At each medial and lateral condyle, four regions of interest (ROI) were manually defined based on the cartilage covered by the 3D surface model of the medial and lateral menisci. RESULTS: The 3D maps showed a relatively inhomogeneous distribution of cartilage T2 on the medial and lateral condyles. Cartilage T2 values in the internal half of the weight-bearing zone were significantly higher than those in all other zones on both lateral and medial condyles. CONCLUSIONS: Analysis of 3D distribution of femoral cartilage T2 may be valuable in determining the site-specific normal range of cartilage T2 in the healthy knee joint.

Application of computed tomography-based navigation for revision total hip arthroplasty.

The usefulness of navigation systems for revision total hip arthroplasty (THA) remains unclear. The purpose of this study was to evaluate the accuracy of cup positioning using a navigation system in revision THA. Cup alignment of thirty revision cases was evaluated. Data were also compared with those of 30 navigated primary THA cases. In the revision THA group, mean difference in postoperative measurement from preoperative plan was 0.5 ± 4° (range, -9° to 8°) for inclination and -0.07° ± 5° (-14° to 13°) for anteversion. Mean difference in postoperative measurement from intraoperative record was 0.7° ± 3° (-5° to 8°) for inclination and -0.7° ± 3° (-12° to 5°) for anteversion. Compared with the primary THA group, none of these parameters were significantly different. This navigation system was useful even in revision THA.

Modular acetabular reconstructive cup in acetabular revision total hip arthroplasty at a minimum ten year follow-up.

PURPOSE: Modular acetabular reconstructive cups have been introduced in an attempt to offer initial rigid fixation by iliac lag screws and ischial pegs, to support bone grafts with a flanged metal socket, and to restore original hip center in acetabular revision. The purpose of this study was to clarify minimum ten year follow-up results of this cup system with morsellised allografts in revision cases. METHODS: We retrospectively investigated 54 acetabular revisions at a mean of 11 years (range, ten to 14 years). The indications were Paprosky's type 2B (eight hip), 2C (eight hips), 3A (23 hips), 3B (nine hips), and 4 (six hips). RESULTS: Using aseptic loosening as the endpoints, the survival rate was 89.3 % (95 % CI 81-98). Radiographically, one type 3A hip, three type 3B hips and one type 4 hip showed aseptic loosening while no type 2 hips or no cemented cups showed loosening. CONCLUSIONS: The modular reconstructive cups for acetabular revision showed bone stock restoration and stable implantation.

High survival of dome pelvic osteotomy in patients with early osteoarthritis from hip dysplasia.

BACKGROUND: The Chiari osteotomy reportedly has a 60% to 91% survival rate at a minimum 20 years followup. The dome pelvic osteotomy (DPO) has the advantage of allowing a larger weightbearing surface, and congruity in the sagittal plane presumably would reduce the joint contact stress and perhaps increase longevity. QUESTIONS/PURPOSES: We determined: (1) the survival after DPO at a minimum 25-year followup, (2) patient function, (3) acetabular coverage, and (4) factors influencing conversion to THA. METHODS: We retrospectively reviewed 50 patients (59 hips) with developmental dysplasia of the hip (DDH) treated with DPO. The preoperative radiographic stages were graded as prearthritis (18 hips), early osteoarthritis (25 hips), and advanced osteoarthritis (16 hips). We performed a Kaplan-Meier survival analysis with THA conversion as the end point. We determined various radiographic parameters reflecting coverage, and compared demographic information for hips without and with THA conversion using multivariate logistic regression analysis. The minimum followup was 25 years (mean, 27.5 years; range, 25-32 years). RESULTS: Survival for all hips was 63.6% (95% CI, 51-76) at 27.5 years and that for hips with prearthritis and early osteoarthritis before the surgery was 79.1% (95% CI, 63-91). Twenty-one hips (36%) had undergone THAs at a mean 18.3 years (range, 2.5-25 years). At the last followup, pain, walking ability, and acetabular coverage improved. We identified four factors predicting THA conversion: greater age, presence of a preoperative Trendelenburg sign, higher preoperative radiographic osteoarthritis grade, and smaller postoperative acetabular head index (AHI) predicted conversion to THA. CONCLUSIONS: DPO is a reasonable treatment option for patients with DDH and prearthritis or early osteoarthritis, with high survival at greater than 25 years.