Decreased Analgesic Effect of Tramadol in Japanese Patients with CYP2D6 Intermediate Metabolizers after Orthopedic Surgery.

Tramadol is metabolized by CYP2D6 to an active metabolite, which in turn acts as an analgesic. This study aimed to investigate the impact of CYP2D6 genotype on the analgesic effect of tramadol in clinical practice. A retrospective cohort study was performed in patients treated with tramadol for postoperative pain after arthroscopic surgery for rotator cuff injury during April 2017-March 2019. The impact of CYP2D6 genotypes on the analgesic effects was assessed by the numeric rating scale (NRS) pain scoring and analyzed by the Mann-Whitney U test. Stepwise multiple linear regression analysis was performed to identify predictive factors for the area under the time-NRS curve (NRS-AUC), which was calculated using the linear trapezoidal method. Among the 85 enrolled Japanese patients, the number of phenotypes with CYP2D6 normal metabolizer (NM) and intermediate metabolizer (IM) was n = 69 (81.1%) and n = 16 (18.9%), respectively. The NRS and NRS-AUC in the IM group were significantly higher than those in the NM group until Day 7 (p < 0.05). The multiple linear regression analysis indicated that the CYP2D6 polymorphism was a prediction factor of the high NRS-AUC levels in Days 0-7 (ß = 9.52, 95% CI 1.30-17.7). In IM patients, the analgesic effect of tramadol was significantly reduced one week after orthopedic surgery in clinical practice. Therefore, dose escalation of tramadol or the use of alternative analgesic medications can be recommended for IM patients.

Expression of proinflammatory cytokines and proinsulin by bone marrow-derived cells for fracture healing in long-term diabetic mice.

BACKGROUND: Diabetes mellitus (DM) causes bone dysfunction due to poor bone quality, leading to severe deterioration in patient of quality of life. The mechanisms of bone metabolism in DM remain unclear, although chemical and/or mechanical factors are known to disrupt the homeostasis of osteoblasts and osteoclasts. The purpose of this study was to identify the changes of osteoblasts and osteoclasts under long-term hyperglycaemic conditions, using a mouse fracture model of long-term hyperglycemia (LT-HG). METHODS: C57BL/6J mice and green fluorescent protein (GFP) -positive bone marrow transplanted C57BL/6J mice with LT-HG, maintained under a state of hyperglycaemia for 2 months, were used in this study. After the experimental fracture, we examined the immunohistochemical expression of proinsulin and tumor necrosis factor (TNF) -α at the fracture site. C57BL/6J fracture model mice without hyperglycaemia were used as controls. RESULTS: In the LT-HG mice, chondrocyte resorption was delayed, and osteoblasts showed an irregular arrangement at the callus site. The osteoclasts were scattered with a decrement in the number of nuclei. The expression of proinsulin was confirmed in bone marrow derived cells (BMDCs) with neovascularization 2 and 3 weeks after fracture. Immunopositivity for TNF-α was also confirmed in immature chondrocytes and BMDCs with neovascularization at 2 weeks, and the number of positive cells was not decreased at 3 weeks. Examination of GFP-grafted hyperglycaemic mice showed that the majority of cells at the fracture site were GFP-positive. Immunohistochemistry showed that the rate of double positives was 15% for GFP and proinsulin and 47% for GFP and TNF-α. CONCLUSION: LT-HG induces an increase in the number of proinsulin and TNF-α positive cells derived from BMDCs. We suggest that proinsulin and TNF-α positive cells are involved in both bone formation and bone resorption after fracture under hyperglycaemic conditions, resulting in the delay of bone healing.

Phenotypic classification of knee osteoarthritis according to pain mechanisms; a clinical observational study.

BACKGROUND: Pain in knee osteoarthritis is considered to be nociceptive. Recently, involvement of neuropathic pain and psychosocial factors in knee osteoarthritis has been reported. However, the following details are unclear: 1) How often are neuropathic pain and psychosocial factors involved? And 2) Which patients are associated with neuropathic pain and psychosocial factors? METHODS: In 104 patients with knee osteoarthritis, we evaluated neuropathic pain factor with a painDETECT questionnaire and catastrophic thinking using the pain catastrophizing scale. Pain intensity was assessed using the visual analog scale; patients with scores below the median were defined as low-pain group and others as high-pain group. Radiographic severity was categorized according to the Kellgren-Lawrence classification, with grades I-II and III-IV defined as low- and high-grades, respectively. We compared the painDETECT and pain catastrophizing scale scores between the low- and high-pain groups and low- and high-grade groups. Furthermore, the painDETECT and pain catastrophizing scale scores were compared among the following four groups: low-grade/low-pain, low-grade/high-pain, high-grade/low-pain, and high-grade/high-pain. RESULTS: Neuropathic pain factor and catastrophic thinking were found in 16% and 34% of patients, respectively. There were no significant differences in both painDETECT and pain catastrophizing scale scores between the two pain intensity groups. Between the two groups of radiographic severity, there was no significant difference in the painDETECT scores; however, the pain catastrophizing scale score was significantly high in the low-grade group. In addition, there was no significant difference in the painDETECT scores among the four groups; however, the pain catastrophizing scale scores were significantly higher in low-grade/high-pain than in high-grade/low-pain patients. CONCLUSIONS: Therefore, 64% had only nociceptive pain factor. Catastrophic thinking was strong in patients with low radiographic severity, especially in those with high pain intensity. Patients with neuropathic pain factor could not be identified from radiographic severity and pain intensity.

Good Postoperative Flexion Angle Improves Knee Function and Improvement of Flexion Angle Increases Patient Satisfaction After Total Knee Arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) is a well-established procedure for treating knee joint diseases. However, the postoperative range of motion (ROM) varies and is an important indicator of TKA success. Recently, patient-reported outcome measures (PROMs) and patient satisfaction have drawn attention. However, the relationship between ROM and knee function obtained by PROM and satisfaction is not well understood. METHODS: We retrospectively reviewed the data of 375 patients who underwent 500 primary TKA procedures. We measured the ROM before and after surgery. Knee joint function was evaluated using the Knee Injury Osteoarthritis Outcome Score, a PROM, and patients were classified into good function and poor function groups. Patient satisfaction was evaluated on a 5-graded scale as overall satisfaction, and patients were divided into a satisfied or a dissatisfied group according to the obtained scores. ROM was compared between the 2 groups, then significantly different factors were analyzed using multiple logistic regression analysis. Moreover, cut-off points of ROM for obtaining good function and patient satisfaction were determined using ROC curve analysis. RESULTS: The postoperative flexion angle had a significant effect on knee function (P < .001). The cut-off value of the postoperative flexion angle for good knee function was 120°. The improvement in flexion angle had a significant effect on patient satisfaction (P = .004). The cut-off value for the improvement in the flexion angle was 5°. CONCLUSION: The postoperative flexion angle had a significant effect on knee function and improvement in the flexion angle had a significant effect on patient satisfaction.

Consideration of differences in drug usage between young-onset and elderly-onset rheumatoid arthritis with target of low disease activity.

OBJECTIVES: Elderly-onset rheumatoid arthritis (EORA) is reported to differ from young-onset rheumatoid arthritis (YORA) with regard to patient background and drug treatment. We examined the amount of drug administered to patients who achieved low disease activity (LDA) for rheumatoid arthritis at our hospital. METHODS: Demographics, clinical history, and treatments were compared between patients with EORA (n = 70) and YORA (n = 190). RESULTS: There was a significant difference in the average age (73.8 vs. 57.8 years), disease duration (6.66 vs. 14.7 years), and sex (62.9% males vs. 83.7% females), but no difference in rheumatoid factor positivity (85.3% vs. 80.7%), anti-citrullinated peptide antibody positivity (86.5% vs. 87.7%), simplified disease activity index (4.28 vs. 4.59), or disease activity score 28-CRP (1.99 vs. 2.04) in the EORA and YORA groups, respectively. There were also no significant differences in prednisolone use (37.1% vs. 36.3%), amount of methotrexate administered (MTX) (1.45 vs. 1.41 mg), and MTX use (55.7% vs. 65.3%). However, the MTX dose (2.89 vs. 4.09 mg/week, p = .011) and overall biologics use (32.9% vs. 56.3%, p = .0012) were significantly lower in patients with EORA than in those with YORA. CONCLUSION: Patients with EORA may be able to achieve LDA with lower drug dosage than those with YORA.

ß-Angles of hips with femoroacetabular impingement versus asymptomatic normal hips in a Japanese population: A CT-based observational clinical study.

BACKGROUND: The beta angle (ß-angle)-although used to assess femoroacetabular impingement (FAI)-has not been well evaluated. This study aimed to measure the ß-angle on multiradial computed tomography (CT) slice images of both hips with symptomatic FAI and asymptomatic normal hips to determine its optimal cutoff value for detecting FAI in a Japanese population. METHODS: CT was performed with each subject supine. The ß-angle was measured on seven radial slices (designated R0, R15, R30, R45, R60, R75, R90) that were generated at 15° intervals from the oblique axial slice through the center of the femoral neck. An a priori power analysis was performed. The measurements were made in 20 FAI hips (FAI group) and 23 asymptomatic normal hips (ANH group). Cutoff values were evaluated using receiver operating characteristic curves. RESULTS: The mean ß-angles of the FAI and ANH groups at R0, R15, R30, R45, R60, R75, and R90° were, respectively, 73.6° and 84.2°, 66.0° and 79.3°, 57.2° and 69.2°, 48.1° and 63.1°, 46.7° and 62.5°, 50.0° and 63.7°, and 53.7° and 65.9°. For all slices, the ß-angle was significantly smaller in the FAI group than the ANH group. The optimal ß-angle cutoff values for diagnosing FAI at R0, R15, R30, R45, R60, R75, and R90 were 73.9°, 70.2°, 61.4°, 55.7°, 53.6°, 59.4°, and 60.9°, respectively. The respective specificities and sensitivities of the cutoff values at R0, R15, R30, R45, R60, R75, and R90 were 78.3% and 65.0%, 82.6% and 70.0%, 73.9% and 60.0%, 73.9% and 75.0%, 95.7% and 75.0%, 69.6% and 95.0%, and 78.3% and 80.0%. CONCLUSIONS: In all radial slices, the ß-angle was significantly smaller in the hips with symptomatic FAI than in the asymptomatic normal hips. The most useful cutoff value for diagnosing FAI was a ß-angle of 53.6° at R60.

Aortic pulsation prevents the development of ossification of anterior longitudinal ligament toward the aorta in patients with diffuse idiopathic skeletal hyperostosis (DISH) in Japanese: Results of chest CT-based cross-sectional study.

BACKGROUND: The development and etiology of diffuse idiopathic skeletal hyperostosis (DISH) were far from complete understanding. Even the precise mechanism of the development of its typical right-sided ossification of the anterior longitudinal ligament (OALL) frequently compared to 'flowing candle wax', a hallmark of DISH, remains unknown. METHODS: The participants of this study were 261 individuals (31 females and 230 males) diagnosed as DISH according to the criteria established by Resnick and Niwayama extracted from a consecutive 3013 patients who have undergone chest CT for the examination of pulmonary diseases in our institute. The patients with previous thoracic spine surgery and younger than 15 years old were excluded. Chest CT data were converted to the condition suitable for bone evaluation by the software application. The positional relationship between thoracic aorta and OALL, the morphology of the OALL adjacent to the aorta and the presence of calcification of the aortic wall adjacent to the OALL were studied. RESULTS: Of 261 individuals with DISH, we found that thoracic aorta was localized adjacent to the OALL (AD-group) in 123 cases (47%), whereas 138 cases (53%) were not (NAD-group). All OALL in AD-group was localized between T6 and T12. The shape of the OALL adjacent to the aorta was either flat or concave except for one. No case showed obvious calcification of the aortic wall adjacent to the OALL in AD-group. CONCLUSIONS: The aortic pulsation might play an important role in inhibit the development of the OALL toward the aorta in DISH. It is likely that establishment of the optimal condition of the pulsation stress simulating aortic pulsation and its delivery system can achieve arresting, slowing the progression and/or changing the morphology of the ossified lesions.

P2X7 ionotropic receptor is functionally expressed in rabbit articular chondrocytes and mediates extracellular ATP cytotoxicity.

Extracellular ATP regulates various cellular functions by engaging multiple subtypes of P2 purinergic receptors. In many cell types, the ionotropic P2X7 receptor mediates pathological events such as inflammation and cell death. However, the importance of this receptor in chondrocytes remains largely unexplored. Here, we report the functional identification of P2X7 receptor in articular chondrocytes and investigate the involvement of P2X7 receptors in ATP-induced cytotoxicity. Chondrocytes were isolated from rabbit articular cartilage, and P2X7 receptor currents were examined using the whole-cell patch-clamp technique. ATP-induced cytotoxicity was evaluated by measuring caspase-3/7 activity, lactate dehydrogenase (LDH) leakage, and prostagrandin E2 (PGE2) release using microscopic and fluorimetric/colorimetric evaluation. Extracellular ATP readily evoked a cationic current without obvious desensitization. This ATP-activated current was dose related, but required millimolar concentrations. A more potent P2X7 receptor agonist, BzATP, also activated this current but at 100-fold lower concentrations. ATP-induced currents were largely abolished by selective P2X7 antagonists, suggesting a predominant role for the P2X7 receptor. RT-PCR confirmed the presence of P2X7 in chondrocytes. Heterologous expression of a rabbit P2X7 clone successfully reproduced the ATP-induced current. Exposure of chondrocytes to ATP increased caspase-3/7 activities, an effect that was totally abrogated by P2X7 receptor antagonists. Extracellular ATP also enhanced LDH release, which was partially attenuated by the P2X7 inhibitor. The P2X7 receptor-mediated elevation in apoptotic caspase signaling was accompanied by increased PGE2 release and was attenuated by inhibition of either phospholipase A2 or cyclooxygenase-2. This study provides direct evidence for the presence of functional P2X7 receptors in articular chondrocytes. Our results suggest that the P2X7 receptor is a potential therapeutic target in chondrocyte death associated with cartilage injury and disorders including osteoarthritis.

Subchondral Insufficiency Fracture of the Femoral Head in a Pregnant Woman with Pre-existing Anorexia Nervosa.

Subchondral insufficiency fracture (SIF) is a fragility fracture secondary to osteoporosis that leads to collapse of the femoral head with no evidence of osteonecrosis. SIF of the femoral head has been reported in adults of varying ages and both sexes, but it has never been reported to occur in pregnant women. Herein, we describe a 40-year-old primiparous patient with pre-existing anorexia nervosa who developed SIF of the femoral head in the third trimester. At 29 weeks of gestation, the patient complained of sudden pain on walking in both hips. Despite the bed rest, her hip pain increased; consequently, cesarean section was performed at 36 weeks. After delivery, plain radiographs showed that the left femoral head was collapsed. Dual-energy X-ray absorptiometry indicated that the patient was osteoporotic. The magnetic resonance imaging (MRI) of her hips showed the findings that were compatible with SIF. Her left hip pain worsened during follow-up, and a radiograph showed progressive collapse of the left femoral head. The patient then underwent left bipolar hip arthroplasty 18 months after delivery, and she was diagnosed with SIF histopathologically. This is the first report of SIF in a pregnant woman that may reflect pregnancy-associated osteoporosis. SIF in pregnancy might be overlooked or misdiagnosed because the MRI findings have several overlaps with those of other hip disorders. Precise diagnosis of SIF in pregnancy may contribute to a better outcome by avoiding early arthroplasty in young women and appropriate evaluation of the osteopenic status of the patient.

Physeal Bar Resection Under Guidance With a Navigation System and Endoscopy for Correction of Distal Radial Deformities After Partial Growth Plate Arrest.

Partial growth plate arrest caused by trauma may lead to severe deformity and dysfunction. The Langenskiöld method is a surgical technique that involves resection of the physeal bar causing partial growth plate arrest. However, it is a technically demanding procedure. We used the Langenskiöld method under guidance with a navigation system and endoscopy and obtained good results in 2 cases. We consider that use of these tools can be a helpful adjunct to the carrying out this procedure.

Wnt signaling pathway correlates with ossification of the spinal ligament: A microRNA array and immunohistochemical study.

BACKGROUND: Ossification of the posterior longitudinal ligament or the ligamentum flavum parallels endochondral ossification. Cell differentiation at the ossification front is known to be important during this process, although the factors regulating its initiation and progression are still unclear. The purpose of this study was to identify factors important for the regulation of chondrocyte/osteoblast differentiation during spinal ossification. METHODS: Ligamentum flavum tissue was isolated from 25 patients who underwent decompressive surgery for cervical ossification of the posterior longitudinal ligament. Tissue sections were used for in vitro culture to obtain primary cells through migration methods. To identify microRNAs associated with ossification of the posterior longitudinal ligament, cultured cells were prepared from the ligamentous tissue (n = 4; continuous type) or from control ligamentous samples harvested from patients with cervical spondylosis without spinal ossification, and analyzed using a microRNA array. The ligamentous sections were also examined by immunohistochemistry for the expression of candidate microRNA target genes. RESULTS: The microRNA array identified 177 factors; 12 of which were expressed at significantly different levels in patients with ossification of the posterior longitudinal ligament compared to those in control patients. The hsa-miR-487b-3p was down-regulated in patients with ossification of the posterior longitudinal ligament, which met the false discovery rate of <0.05. This microRNA was predicted to regulate the expression of genes involved in Wnt signaling. Furthermore, immunohistochemistry of Wnt signaling proteins, including Wnt 3a, LRP5/6, and beta-catenin, revealed positive expression in mesenchymal cells and/or premature chondrocytes at the ossification front. CONCLUSION: Our results suggested that down-regulation of miR-487b-3p plays an important role in the initiation of Wnt signaling during the ossification process. Wnt signaling may regulate both chondrocyte and osteoblast differentiation and the specification of endochondral ossification in the pathogenesis of ossification of the posterior longitudinal ligament or the ligamentum flavum.

Multiplanar evaluation of radiological findings associated with acetabular dysplasia and investigation of its prevalence in an Asian population: a CT-based study.

BACKGROUND: Acetabular dysplasia (AD) is a well-known cause of osteoarthritis (OA) of the hip, with its prevalence previously determined on plain radiography. The prevalence of preexisting AD was reported as 7.3% in a patient-based Asian population. Although computed tomography (CT) could evaluate AD in multiple planes, its prevalence using multiplanar CT images has not been reported. We investigated its prevalence with CT on coronal, axial, and sagittal planes and then determined if adding the axial and sagittal planes enhanced the investigation. METHODS: We retrospectively examined 52 consecutive Japanese individuals (mean age 59.4 years) who had undergone CT for conditions unrelated to hip disorders. The inclusion criteria of CT images were (1) reconstructed axial slice thickness of ≤1 mm and (2) normal pelvic rotations and tilt. Exclusion criteria were (1) age <20 years, (2) neither hip center could be clearly detected, (3) evidence of hip OA. The parameters used to define AD on the coronal plane were the center-edge angle, Sharp angle, acetabular index, acetabular depth ratio, and acetabulum head index. The anterior and posterior acetabular sector angles were used as axial parameters and the vertical-center-anterior margin angle as the sagittal parameter. AD prevalence was calculated using multiplanar images and then compared with the previously reported Asian prevalence using 95% confidence intervals (CI). In this study, we defined "prevalence" as the proportion of subjects who had AD in at least one hip. RESULTS: The mean prevalence of AD on coronal, axial, and sagittal planes was 16.9, 15.4, and 7.7%, respectively. The lowest prevalence found by combining the three planes was 25.0% (95% CI 15.2-38.2%). This prevalence was significantly higher than that in the previously reported Asian population (7.3%). CONCLUSIONS: At the lowest estimate, the prevalence of AD evaluated in three planes was more than twice as high as the previously reported prevalence in Asians when we investigated its prevalence using multiplanar images. The prevalence of AD in the axial and sagittal planes was not negligible. We therefore suggest that it is important to add axial and sagittal planes' data when investigating the prevalence of AD.

Prevalence of thoracic diffuse idiopathic skeletal hyperostosis (DISH) in Japanese: Results of chest CT-based cross-sectional study.

BACKGROUND: The epidemiology and etiology of diffuse idiopathic skeletal hyperostosis (DISH) remain obscure. To date, to the best of our knowledge, there is no study that precisely evaluated the prevalence of thoracic DISH based on computed tomography (CT) data in large number of non-operated cohort with wide age distribution. METHODS: The participants of this study were the consecutive patients who have undergone chest CT for the examination of pulmonary diseases in our institute. The patients with previous thoracic spine surgery and younger than 15 years old were excluded. Chest CT data were reconstructed in the condition suitable for bone evaluation by the software application. Definitive diagnosis of DISH was determined according to the criteria established by Resnick and Niwayama. Prevalence and distribution of thoracic DISH were reviewed and the data was statistically analyzed. RESULTS: Total 3013 patients (1261 females and 1752 males) with the mean age of 65 years were recruited. The CT-based evidence of thoracic DISH was noted in 261 individuals (31 females and 230 males) (8.7%), and their mean age was 73 years. Statistical analyses revealed that thoracic DISH had a significant male preponderance. The mean age of thoracic DISH positive individuals was significantly higher than that of thoracic DISH negative individuals. There was significant difference of bone mass index (BMI) between thoracic DISH positive and negative individuals. Thoracic DISH was noted after the age of 40s with the highest distribution found at the age of 70s. No thoracic DISH localizes only higher thoracic region was found. CONCLUSIONS: The CT-based prevalence of thoracic DISH in Japanese was 8.7%. Thoracic DISH has a significant predisposition to elderly male with high BMI.

Prevalence of pincer, cam, and combined deformities in Japanese hip joints evaluated with the Japanese Hip Society diagnostic guideline for femoroacetabular impingement: A CT-based study.

BACKGROUND: Femoroacetabular impingement (FAI) is thought to be associated with hip osteoarthritis. We investigated the prevalences of radiologic deformities of the pincer, cam, and their combinations in Japanese hip joints using computed tomography (CT) according to the Japanese Hip Society diagnostic guideline for FAI. METHODS: Multi-slice CT images were evaluated. Pincer deformities were defined as: type 1: center-edge angle (CE) ≥40°; type 2: CE ≥ 30° and acetabular roof obliquity ≤0°; type 3: CE ≥ 25° and retroverted acetabulum. Cam deformities were defined as: type 1: CE ≥ 25°, α-angle ≥55°, and head-neck offset ratio <0.14; type 2: CE ≥ 25°, α-angle ≥55°, and herniation pit positive; type 3: CE ≥ 25°, α-angle ≥55°, and pistol grip deformity positive. RESULTS: We studied 128 hips. Pincer was detected in 35.9% (type 1, 12.5%; type 2, 18.0%; type 3, 13.3%). Cam was detected in 24.2% (type 1, 23.4%; type 2, 7.8%; type 3, 10.9%). Combined deformities were detected in 10.2%. Type 3 pincer/type 1 cam was the most frequent combined deformity compared with all combined deformities. All of the cam deformities, total combined deformities, and all radiological FAIs appeared significantly more often in men. CONCLUSIONS: When we used this guideline to diagnose FAI in a Japanese population, radiological FAI was common, and pincer deformities were more common than cam deformities. The most frequent seen pincer, cam, and combined deformities was type 2 pincer, type 1 cam, and the combination of type 3 pincer/type 1 cam, respectively.

Joint Arthroplasty With Osteochondral Grafting From the Knee for Posttraumatic or Degenerative Hand Joint Disorders.

PURPOSE: To describe the operative procedure and report the clinical outcomes of articular surface reconstruction for various hand joint disorders using autologous osteochondral grafts from the knee. METHODS: Ten patients underwent articular surface reconstruction for hand joint disorders with autologous osteochondral grafts from the patellofemoral joint. Mean patient age was 35 years (range, 15-52 y). The patients were followed for an average of 48 months (range, 16-89 mo). Arthroplasty was performed on the metacarpophalangeal joint in 4 cases, and on the proximal interphalangeal joint in 6 cases. The patients' clinical outcomes were evaluated with joint range of motion, visual analog scale (0-10 points), and Disabilities of the Arm, Shoulder, and Hand (DASH) score. Histological examination was performed in 3 cases after surgery. RESULTS: Graft union was confirmed in all cases without radiographic evidence of resorption or necrosis. Follow-up radiographic examinations showed good graft incorporation without signs of osteoarthritis such as joint space narrowing. The finger flexion-extension arc improved significantly from an average of 21° to 61°. The mean visual analog scale also improved significantly from 7.0 to 1.5. The mean total active motion showed a significant improvement from 151° before surgery to 201° after surgery, and the mean DASH score improved significantly from 33 to 12. There were no significant differences for the arc of finger motion and DASH score between metacarpophalangeal and proximal interphalangeal joint disorders or between hemiarthroplasty and total joint arthroplasty. Histological examination revealed viable chondrocytes in the implanted cartilage. CONCLUSIONS: Autologous osteochondral grafting from the patellofemoral joint provided satisfactory outcomes and may be a useful option for joint surface reconstruction of traumatic or degenerative hand joint disorders. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Prevalence of radiological femoroacetabular impingement in Japanese hip joints: detailed investigation with computed tomography.

BACKGROUND: Femoroacetabular impingement (FAI) has been highlighted as a new etiology for osteoarthritis of the hip, and its prevalence has been reported in the past decade. In the present study, we performed a detailed investigation of the anatomical parameters related to FAI and calculated the prevalence of FAI-related findings in asymptomatic Japanese hip joints using computed tomography. METHODS: We evaluated high-resolution reconstructed multislice computed tomography images in patients who had undergone computed tomography imaging in our institution for conditions unrelated to hip disorders. The examined parameters were as follows: center-edge (CE) angle; acetabular index; acetabular anteversion (five slices in the axial plane); and asphericity angle of the femoral head (AAFH) (six slices in multiple radial planes). The AAFH in the oblique axial slice through the center of the femoral neck is the so-called α-angle. We then examined the accurate prevalence of FAI-related findings in Japan. RESULTS: We investigated a total of 103 hips. The mean age of the subjects was 59.4 years. The mean CE angle was 31.1° and the mean acetabular index was 7.0°. The mean acetabular anteversion was 20.3° at the level of the hip center, and decreased as the slice level neared the superior margin of the femoral head. The mean AAFH ranged from 40.6° to 49.2° in the radial planes. The AAFH was largest at 60° rotated slice from the oblique axial slice through the center of the femoral neck. The prevalence of FAI-related findings in these Japanese hip joints was assessed as follows. An AAFH of >50° in any slice was detected in 51.5 % of the hips, and acetabular anteversion was negative for all images in 16.5 % of the hips, meaning that a total of 56.3 % of the images met the criteria for radiological FAI. CONCLUSIONS: With consideration of our results, we emphasize that "anatomical or radiological FAI" is not uncommon in Japanese hips. Therefore, the diagnosis of FAI should be performed with the clinical findings taken into account.

Improved quality of cartilage repair by bone marrow mesenchymal stem cells for treatment of an osteochondral defect in a cynomolgus macaque model.

BACKGROUND AND PURPOSE: Integration of repaired cartilage with surrounding native cartilage is a major challenge for successful tissue-engineering strategies of cartilage repair. We investigated whether incorporation of mesenchymal stem cells (MSCs) into the collagen scaffold improves integration and repair of cartilage defects in a cynomolgus macaque model. METHODS: Cynomolgus macaque bone marrow-derived MSCs were isolated and incorporated into type-I collagen gel. Full-thickness osteochondral defects (3 mm in diameter, 5 mm in depth) were created in the patellar groove of 36 knees of 18 macaques and were either left untreated (null group, n = 12), had collagen gel alone inserted (gel group, n = 12), or had collagen gel incorporating MSCs inserted (MSC group, n = 12). After 6, 12, and 24 weeks, the cartilage integration and tissue response were evaluated macroscopically and histologically (4 null, 4 gel, and 4 MSC knees at each time point). RESULTS: The gel group showed most cartilage-rich reparative tissue covering the defect, owing to formation of excessive cartilage extruding though the insufficient subchondral bone. Despite the fact that a lower amount of new cartilage was produced, the MSC group had better-quality cartilage with regular surface, seamless integration with neighboring naïve cartilage, and reconstruction of trabecular subchondral bone. INTERPRETATION: Even with intensive investigation, MSC-based cell therapy has not yet been established in experimental cartilage repair. Our model using cynomolgus macaques had optimized conditions, and the method using MSCs is superior to other experimental settings, allowing the possibility that the procedure might be introduced to future clinical practice.

Ultrasound-assisted closed reduction of distal radius fractures.

PURPOSE: To assess the accuracy and ability of ultrasound for monitoring closed reduction for distal radius fractures. METHODS: Consecutive patients undergoing ultrasound-guided closed reduction of acute, displaced distal radius fractures between January 2003 and December 2006 at our department were enrolled. The control group was extracted from patients who underwent a closed reduction for similar fractures under fluoroscopy or without any imaging assistance. To confirm the accuracy of the ultrasonography measurements, displacement distance values were compared with those on radiographic imaging before and after reduction. X-ray parameters for pre- and postreduction, reduction time, total cost, and success rate were compared between the ultrasound-guided and the control groups. RESULTS: The ultrasound-guided group consisted of 43 patients (mean age, 68 y) and the control group consisted of 57 patients, which included 35 patients (mean age, 74 y) with fluoroscopic reduction and of 22 patients (mean age, 72 y) with reduction unaided by imaging. There were no significant displacement differences between radiographic and ultrasound measurements. In x-ray parameters for pre- and postreduction, there were no significant differences between the 2 groups. Ultrasound-guided reduction took longer than the other 2 methods. The success rate of the ultrasound and the fluoroscopic groups were similar (95% and 94%, respectively). CONCLUSIONS: Our data suggest that ultrasound assistance can aid reduction of distal radius fractures as well as fluoroscopy. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.