Effects of body mass index and range of motion on intraoperative change in pelvic tilt during total hip arthroplasty using the direct anterior approach.

BACKGROUND: Intraoperative pelvic tilt changes that occurs during total hip arthroplasty (THA) in the supine position affects cup placement and sometimes causes malalignment. The relationship between body mass index (BMI) and pelvic movement has been reported for some procedures, but not the direct anterior approach (DAA). The purpose of this study was to investigate intraoperative pelvic tilt changes that occurs during DAA. METHODS: In this single-center, retrospective study, we reviewed 200 hips that underwent primary THA via DAA in the supine position using an accelerometer-based navigation system. Intraoperative changes in pelvic tilt and axial rotation from the start of surgery to cup placement were assessed using the navigation system. Preoperative clinical factors that increased pelvic tilt and axial rotation toward the surgical side by > 10° were analyzed via univariate and multiple logistic regression analyses. RESULTS: The mean pelvic tilt value increased by 7.6° ± 3.8° (95% confidence interval [CI], 7.1-8.2; range, - 5.0-19.0) intraoperatively, and the axial rotation increased by 3.2° ± 2.7° (95% CI, 2.7-3.7; range, - 13.0-12.0). Univariate analysis revealed that the group with increased pelvic tilt showed significantly greater range of abduction and internal rotation, and significantly lower BMI than the group with no increased tilt. Pre-incisional pelvic tilt was significantly greater in the group with increased axial rotation than in the group with no increased rotation. On logistic regression analysis, BMI (odds ratio [OR], 0.889; 95% CI, 0.809-0.977; p = 0.014) and the range of internal rotation (OR, 1.310; 95% CI, 1.002-1.061; p = 0.038) were predictors of large increases in pelvic tilt. No predictors of large increases in axial rotation were identified. CONCLUSION: Significant forward pelvic tilt was observed in patients with a low BMI values and high ranges of internal rotation via THA using the DAA. Findings indicated that surgeons should pay attention to intraoperative pelvic movements, which may help identify patients with significant pelvic tilt changes.

Curved Intertrochanteric Varus Osteotomy vs Total Hip Arthroplasty for Osteonecrosis of the Femoral Head in Patients Under 50 Years Old.

BACKGROUND: Given recent advances in total hip arthroplasty (THA), curved intertrochanteric varus osteotomy (CVO) is not indicated as a treatment for osteonecrosis of the femoral head (ONFH), unless indicated to maintain long-term hip function and achieve patient satisfaction. We aimed to compare the clinical outcomes of CVO with those of THA for treatment of ONFH in young adults <50 years old. METHODS: This comparative study included 105 ONFH patients: 59 patients (65 hips) who underwent CVO and 46 patients (56 hips) who underwent THA. Assessment tools included the Harris hip score (HHS), patient-reported outcomes of the Short Form-36, Oxford hip score, Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire, and University of California, Los Angeles score, together with complication and survival rates. RESULTS: Preoperative HHS was significantly higher in the CVO group than in the THA group (P < .01). At the last follow-up, no between-group differences were noted in HHS, all domains of Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire scores, Oxford hip score, and Short Form-36. University of California, Los Angeles scores and complication rates were comparable: 3% for the CVO and 7% for the THA group. The 10-year survival rate with surgery for any reason as the end point was comparable, at 91.8% for the CVO and 97.7% for the THA group. CONCLUSION: Functional outcomes, survival rate, and sporting activities for patients <50 years old undergoing CVO or THA for ONFH were comparable after a mean follow-up period of 10 years. Strict indications for CVO can help maintain hip function and patient satisfaction equivalent to that for THA, in the long term.

Total Hip Arthroplasty After Periacetabular and Intertrochanteric Valgus Osteotomy.

BACKGROUND: We performed periacetabular osteotomy (PAO) combined with intertrochanteric valgus osteotomy (TVO) to obtain better congruity for patients with acetabular dysplasia and nonspherical femoral head. These patients with PAO-combined TVO demonstrate long-term progression of osteoarthritis, thereby, needing conversion to total hip arthroplasty (THA) and is difficult due to morphological changes. The objective of the present study was to investigate outcomes of patients who underwent THA after PAO-combined TVO. METHODS: We performed 3 groups' case-control study. The participants were 20 patients (20 hips) who underwent THA after PAO-combined TVO (PAO-TVO group); these patients had a mean age at surgery of 56.3 years and underwent postoperative follow-up for a mean period of 6.8 years. For the control group, we included 53 patients (57 joints) who underwent THA after PAO and 76 patients (80 joints) who underwent primary THA for hip dysplasia matching age, sex, and time of surgery. RESULTS: Harris hip score at the last follow-up was significantly poorer in PAO-TVO group compare with PAO group and primary group. Short Form-36 of Physical Component Summary was significantly poorer in PAO-TVO group compared with primary group. The socket position in the PAO-TVO group was significantly superior and lateral compared with that in the primary THA group. Considering socket placement in Lewinnek's safe zone and stem malalignment, there were no significant differences in the 3 groups. CONCLUSION: Harris hip score and Short Form-36-Physical Component Summary for THA after PAO-combined TVO were significantly poorer compared to those of primary THA.

Muscle Damage After Total Hip Arthroplasty Through the Direct Anterior Approach for Developmental Dysplasia of the Hip.

BACKGROUND: Total hip arthroplasty (THA) through the direct anterior approach (DAA) is known to cause less muscle damage than other surgical approaches. However, more complex primary cases, such as developmental dysplasia of the hip (DDH), might often cause muscle damage. The objective of the present study was to clarify the muscle damage observed 1 year after THA through the DAA for DDH using magnetic resonance imaging. METHODS: We prospectively compared the muscle cross-sectional area (M-CSA) and fatty atrophy (FA) in muscles by magnetic resonance imaging and the Harris hip score before and at 1-year follow-up after THA through the DAA in 3 groups: 37 patients with Crowe group 1 DDH (D1), 13 patients with Crowe group 2 and 3 DDH (D2 + 3), and 12 patients with osteonecrosis as a control. RESULTS: THA through the DAA for D1 displayed significantly decreased M-CSA and significantly increased FA in the gluteus minimus (Gmini), the tensor fasciae latae (TFL), and the obturator internus (OI). Patients with D2 + 3 group did not have decreased M-CSA in the TFL or increased FA in the Gmini. Postoperatively, a significant negative correlation was observed between the M-CSA and FA for the OI in patients with D1 and D2 + 3. CONCLUSION: THA through the DAA for DDH caused the damage in the Gmini, the TFL, and the OI; severe damage was observed in the OI, showing increased FA with decreased M-CSA in patients with both D1 and D2 + 3.

Total Hip Arthroplasty After Transtrochanteric Rotational Osteotomy for Osteonecrosis of the Femoral Head: A Mean 10-Year Follow-Up.

BACKGROUND: The objective of the present study was to investigate clinical, quality of life, and radiographic outcomes of patients who underwent total hip arthroplasty (THA) after transtrochanteric rotational osteotomy (TRO) for osteonecrosis of the femoral head (ONFH). METHODS: We performed a case-control study. The participants were 29 patients (34 hips) who underwent THA after TRO (TRO group). These patients had a mean age at surgery of 51.6 years (range, 30-72 years) and underwent postoperative follow-up for a mean period of 10.5 years (range, 3-19 years). For the control group (primary group), we included 58 patients (68 hips) who underwent primary THA for ONFH, matching for age and gender. RESULTS: The Harris Hip Scores at the last follow-up were significantly poorer in the TRO group than in the primary group. Similarly, preoperative and postoperative hip range of motion was significantly poorer in the TRO group than in the primary group. Quality of life (Short Form-36, Oxford Hip Score, and Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire) and complication rates were not significantly different between the groups. The survival rates at 10 years, with revision for any reason as the endpoint, were 81% in the TRO group and 91% in the primary group, showing no significant difference between the groups. The TRO group had a larger average postoperative leg length discrepancy and a higher rate of stem malalignment than the primary group. CONCLUSION: The clinical outcomes of THA after TRO for ONFH were poorer than those of primary THA.

What factors predict the failure of curved intertrochanteric varus osteotomy for the osteonecrosis of the femoral head?

INTRODUCTION: The purpose of this study was to examine the 10-year survivorship and clinical outcome after curved intertrochanteric varus osteotomy (CVO) for the osteonecrosis of the femoral head (ONFH), and to determine what factors predict the failure of this procedure. MATERIALS AND METHODS: We retrospectively reviewed 102 consecutive CVOs in 93 patients diagnosed with ONFH. Mean follow-up duration was 10.1 years (3.0-23.2 years). Factors associated with radiographic failure (secondary collapse and/or osteoarthritic change), conversion to total hip arthroplasty (THA) and low Harris Hip Score (HHS), were assessed. The Kaplan-Meier method was used to estimate survival rate. RESULTS: Radiographic failure occurred in 27 hips (26.5 %), and 11 hips (10.8 %) were converted to THA. The 10-year survival rate was 91.0 % [95 % confidence interval (CI) 83.4-95.2 %] with conversion to THA as the endpoint and 72.4 % (95 % CI 62.3-80.3 %) with radiographic failure as the endpoint. Mean HHS improved from 70.0 preoperatively to 88.1 at the final follow-up (p < 0.001). Multivariate Cox regression analysis showed that postoperative intact ratio <33.3 % [hazard ratio (HR), 11.17; 95 % CI 4.14-30.14] and center-edge (CE) angle <25° (HR 4.91; 95 % CI 1.92-12.55) were independent factors determining radiographic failure. In addition, the multivariate Cox regression analysis showed that postoperative intact ratio <33.3 % (HR 10.65; 95 % CI 2.24-50.53) and CE angle <25° (HR 7.81; 95 % CI 2.17-28.07) were also factors determining conversion to THA. Worse HHSs of <80 were seen in patients with postoperative intact ratio <33.3 % (p < 0.001), CE angle <25° (p < 0.001), and acetabular head index <75 % (p = 0.006). CONCLUSIONS: Postoperative intact ratio <33.3 % and CE angle <25° were identified as independent factors determining radiographic failure and conversion to THA. Therefore, these factors must be taken into consideration when selecting patients for CVO.

Fatal case of cervical blunt vascular injury with cervical vertebral fracture: a case report.

Blunt cerebrovascular injury (BCVI) is usually caused by neck trauma that predominantly occurs in high-impact injuries. BCVI may occur due to damage to both the vertebral and carotid arteries, and may be fatal in the absence of appropriate treatment and early diagnosis. Here, we describe a case of cerebral infarction caused by a combination of a lower cervical spinal fracture and traumatic injury to the carotid artery by a direct blunt external force in a 52-year-old man. Initially, there was no effect on consciousness, but 6 hours later loss of consciousness occurred due to traumatic dissection of the carotid artery that resulted in a cerebral infarction. Brain edema was so extensive that decompression by emergency craniectomy and internal decompression were performed by a neurosurgeon, but with no effect, and the patient died on day 7. This is a rare case of cerebral infarction caused by a combination of a lower cervical spinal fracture and traumatic injury to the carotid artery. The case suggests that cervical vascular injury should be considered in a patient with a blunt neck trauma and that additional imaging should be performed.

Comparison of accuracy of cup position using portable navigation versus alignment guide in total hip arthroplasty in supine position.

BACKGROUND: Accelerometer-based portable navigation systems in supine total hip arthroplasty (THA) have been developed, but there are no reports on the accuracy of cup placement. We aimed to investigate and compare the accuracy of the accelerometer-based portable navigation system versus the acetabular alignment guide placed on the pelvis in THA using the direct anterior approach (DAA). Both devices tracked changes in the pelvic position. METHODS: In this single-centre, retrospective study, we reviewed 115 hips in 113 patients who underwent primary THA via the DAA using an accelerometer-based portable navigation system in the supine position (portable navigation group) and 106 hips in 101 patients who underwent THA using an acetabular alignment guide (alignment guide group) as controls. Hips were evaluated postoperatively using computed tomography to measure cup orientation. The accuracy of cup orientation was compared between the 2 groups. RESULTS: Absolute values of inclination error were 3.1° ± 2.2° and 2.9° ± 2.3° (p = 0.708) in the portable navigation and alignment guide groups and those of anteversion error were 2.8° ± 2.3° and 3.7° ± 2.7°, respectively (p = 0.005). The number of cups placed within 10° of error was 98.3% and 96.2% in the portable navigation and alignment guide groups, respectively (p = 0.304). The portable navigation group had significantly more hips (72.2%) placed within a 5° margin of error than did the alignment guide group (56.6%) (p = 0.016). CONCLUSION: High accuracy in cup placement was achieved using accelerometer-based portable navigation in supine THA. Using a navigation system may contribute to improved long-term outcomes.

Long-term outcomes of curved intertrochanteric varus osteotomy combined with bone impaction grafting for non-traumatic osteonecrosis of the femoral head.

AIMS: We compared the clinical outcomes of curved intertrochanteric varus osteotomy (CVO) with bone impaction grafting (BIG) with CVO alone for the treatment of osteonecrosis of the femoral head (ONFH). METHODS: This retrospective comparative study included 81 patients with ONFH; 37 patients (40 hips) underwent CVO with BIG (BIG group) and 44 patients (47 hips) underwent CVO alone (CVO group). Patients in the BIG group were followed-up for a mean of 12.2 years (10.0 to 16.5). Patients in the CVO group were followed-up for a mean of 14.5 years (10.0 to 21.0). Assessment parameters included the Harris Hip Score (HHS), Oxford Hip Score (OHS), Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ), complication rates, and survival rates, with conversion to total hip arthroplasty (THA) and radiological failure as the endpoints. RESULTS: There were no significant differences in preoperative and postoperative HHS or postoperative OHS and JHEQ between the BIG group and the CVO group. Complication rates were comparable between groups. Ten-year survival rates with conversion to THA and radiological failure as the endpoints were not significantly different between groups. Successful CVO (postoperative coverage ratio of more than one-third) exhibited better ten-year survival rates with radiological failure as the endpoint in the BIG group (91.4%) than in the CVO group (77.7%), but this difference was not significant (p = 0.079). CONCLUSION: Long-term outcomes of CVO with BIG were favourable when proper patient selection and accurate surgery are performed. However, this study did not show improvements in treatment results with the concomitant use of BIG. Cite this article: Bone Joint J 2021;103-B(4):665-671.

Author Correction: Mianserin suppresses R-spondin 2-induced activation of Wnt/ß-catenin signaling in chondrocytes and prevents cartilage degradation in a rat model of osteoarthritis.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Mianserin suppresses R-spondin 2-induced activation of Wnt/ß-catenin signaling in chondrocytes and prevents cartilage degradation in a rat model of osteoarthritis.

Aberrant activation of the Wnt/ß-catenin signaling pathway promotes the progression of osteoarthritis (OA). We previously reported that R-spondin 2 (Rspo2), an activator of the Wnt/ß-catenin signaling, facilitates differentiation of proliferating chondrocytes into hypertrophic chondrocytes by enhancing Wnt/ß-catenin signaling in endochondral ossification. However, the role of Rspo2 in OA remains elusive. Here, we showed that the amounts of Rspo2 protein in synovial fluid were increased in OA patients. We searched for a preapproved drug that suppresses Rspo2-induced Wnt/ß-catenin signaling in chondrogenic cells and reduces joint pathology in a rat model of OA. In Rspo2-treated ATDC5 cells, mianserin, a tetracyclic antidepressant, inhibited Wnt/ß-catenin signaling, increased proteoglycan production, and upregulated chondrogenic marker genes. Mianserin suppressed Rspo2-induced accumulation of ß-catenin and phosphorylation of Lrp6. We identified that mianserin blocked binding of Rspo2 to its receptor Lgr5. We also observed that intraarticular administration of mianserin suppressed ß-catenin accumulation and prevented OA progression in a rat model of OA. We conclude that mianserin suppresses abnormally activated Wnt/ß-catenin signaling in OA by inhibiting binding of Rspo2 to Lgr5.

Serum levels of carotenoids in patients with osteonecrosis of the femoral head are lower than in healthy, community-living people.

PURPOSE: Oxidative stress is closely associated with the pathogenesis of nontraumatic osteonecrosis of the femoral head (ONFH). This study aimed to determine whether the serum levels of antioxidant nutrients were decreased in patients with ONFH. METHODS: We analyzed the serum levels of antioxidant nutrients in 39 patients with ONFH (ONFH group) and 78 age- and gender-matched healthy people (control group) who voluntarily participated in the Yakumo study, which is a comprehensive health examination program. We measured and compared the serum levels of α-tocopherol (vitamin E) and total carotenoids, including zeaxanthin/lutein, ß-cryptoxanthin, lycopene, α-carotene, and ß-carotene, in the ONFH and control groups using high-performance liquid chromatography. RESULTS: The mean serum levels of total carotenoids were significantly lower in the ONFH group than in the control group (2.36 ± 1.26 and 3.79 ± 2.36 µmol/l, respectively, p < 0.001). However, no significant difference was found in α-tocopherol between the two groups (26.37 ± 6.90 µmol/l in the ONFH group and 26.24 ± 6.28 µmol/l in the control group, p = 0.920). Among each carotenoid, the serum levels of zeaxanthin/lutein, lycopene, and ß-carotene were significantly lower in the ONFH group than in the control group ( p < 0.001). CONCLUSIONS: The serum levels of carotenoids were lower in patients with ONFH than in healthy, community-living people. This result suggests that carotenoids may be related to the pathogenesis of ONFH.

Activated FGFR3 prevents subchondral bone sclerosis during the development of osteoarthritis in transgenic mice with achondroplasia.

The purpose of this study is to investigate the morphometric changes of the subchondral bone during the development of osteoarthritis (OA) in transgenic mice with achondroplasia (Fgfr3ach ) carrying a heterozygous gain-of-function mutation in Fgfr3. Two OA models (spontaneously developed with age: The aging model, and surgically induced by destabilization of the medial meniscus: The DMM model) were established. Articular cartilage, epiphysis, and metaphysis of the knee joint were histologically and morphometrically compared between wild-type mice, and Fgfr3ach mice in both OA models. Articular cartilage degeneration was scored according to the Osteoarthritis Research Society International (OARSI) scoring system. Several morphometric parameters including bone mineral density (BMD), bone volume/tissue volume (BV/TV), trabecular bone thickness (Tb.Th), and subchondral bone thickness in the medial tibial plateau (MTP) (Sb.Th med) were quantified by micro-computed tomography (CT). In the aging model, although there were no significant differences in the OARSI score between wild-type mice and Fgfr3ach mice, Sb.Th med and Tb.Th in the epiphysis significantly increased in wild-type mice. In the DMM model, the OARSI score of the medial compartment was significantly lower in Fgfr3ach mice than in wild-type mice. BMD, BV/TV, and Tb.Th in the epiphysis increased in wild-type mice and unchanged in Fgfr3ach mice, and the Sb.Th med was significantly larger in wild-type mice after surgery. Subchondral sclerosis, which preceded the cartilage degeneration, was inhibited in Fgfr3ach mice. Activated FGFR3 signaling prevented sclerotic changes of the subchondral bone and subsequent cartilage degeneration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:300-308, 2018.