A Novel High-Throughput Screening Method for a Human Multicentric Osteosarcoma-Specific Antibody and Biomarker Using a Phage Display-Derived Monoclonal Antibody.

Osteosarcoma is a malignant tumor that produces neoplastic bone or osteoid osteoma. In human multicentric osteosarcoma (HMOS), a unique variant of human osteosarcoma (HOS), multiple bone lesions occur simultaneously or asynchronously before lung metastasis. HMOS is associated with an extremely poor prognosis, and effective treatment options are lacking. Using the proteins in our previously generated HMOS cell lines as antigens, we generated antibodies using a human antibody phage library. We obtained antibody clones recognizing 95 independent antigens and developed a fluorescence probe-based enzyme-linked immunosorbent assay (ELISA) technique capable of evaluating the reactivity of these antibodies by fluorescence intensity, allowing simple, rapid, and high-throughput selection of antibody clones. These results were highly correlated with those using flow cytometry. Subsequently, the HMOS cell lysate was incubated with the antibody, the antigen-antibody complex was recovered with magnetic beads, and the protein bands from electrophoresis were analyzed using liquid chromatography-mass spectrometry (LC/MS). CAVIN1/polymerase I transcript release factor was specifically detected in the HMOS cells. In conclusion, we found via a novel high-throughput screening method that CAVIN1/PTRF is an HMOS-specific cell membrane biomarker and an antigen capable of producing human antibodies. In the future, antibody-drug conjugate targeting of these specific proteins may be promising for clinical applications.

Effects of porous tantalum on periprosthetic bone remodeling around metaphyseal filling femoral stem: a multicenter, prospective, randomized controlled study.

Periprosthetic bone loss due to adaptive bone remodeling is an important unresolved issue in cementless total hip arthroplasty (THA). The use of porous tantalum on the proximal surface of the femoral stem is expected to decrease postoperative bone loss around the prosthesis through early fixation. We conducted a multicenter randomized controlled study to determine if porous tantalum could reduce periprosthetic bone loss after THA. From October 2012 to September 2014, 118 patients (mean age, 61.5 years; 107 females and 11 males) were prospectively enrolled and were randomly allocated at a ratio of 1:1 to either a metaphyseal filling stem with a proximal porous tantalum coating (Trabecular Metal) or a conventional metaphyseal filling stem with fiber mesh coating (VerSys). Patients underwent dual-energy x-ray absorptiometry scans within 1 week after surgery (baseline) and at 6, 12, and 24 months after surgery to assess periprosthetic bone mineral density (BMD) in the 7 Gruen zones. In addition, the Japanese Orthopaedic Association hip score was assessed before surgery and at 6, 12, and 24 months after surgery. In the proximal periprosthetic region (zones 1 and 7), the Trabecular Metal group had significantly smaller reductions in BMD than the VerSys group throughout the study period. In the VerSys group, significant reductions in BMD compared to baseline were seen at each measurement point in all regions, except in zone 6 at 24 months. In the Trabecular Metal group, no significant reductions in BMD relative to baseline were seen in zones 1, 5, or 6 throughout the study period. Both groups demonstrated similar improvement in Japanese Orthopaedic Association hip scores over the study period. This study demonstrated that a proximally coated stem with porous tantalum has superior results over a conventional stem with titanium fiber mesh in terms of periprosthetic bone remodeling.

Mesenchymal Bmp3b expression maintains skeletal muscle integrity and decreases in age-related sarcopenia.

Age-related sarcopenia constitutes an important health problem associated with adverse outcomes. Sarcopenia is closely associated with fat infiltration in muscle, which is attributable to interstitial mesenchymal progenitors. Mesenchymal progenitors are nonmyogenic in nature but are required for homeostatic muscle maintenance. However, the underlying mechanism of mesenchymal progenitor-dependent muscle maintenance is not clear, nor is the precise role of mesenchymal progenitors in sarcopenia. Here, we show that mice genetically engineered to specifically deplete mesenchymal progenitors exhibited phenotypes markedly similar to sarcopenia, including muscle weakness, myofiber atrophy, alterations of fiber types, and denervation at neuromuscular junctions. Through searching for genes responsible for mesenchymal progenitor-dependent muscle maintenance, we found that Bmp3b is specifically expressed in mesenchymal progenitors, whereas its expression level is significantly decreased during aging or adipogenic differentiation. The functional importance of BMP3B in maintaining myofiber mass as well as muscle-nerve interaction was demonstrated using knockout mice and cultured cells treated with BMP3B. Furthermore, the administration of recombinant BMP3B in aged mice reversed their sarcopenic phenotypes. These results reveal previously unrecognized mechanisms by which the mesenchymal progenitors ensure muscle integrity and suggest that age-related changes in mesenchymal progenitors have a considerable impact on the development of sarcopenia.

Tibial rotational alignment after opening-wedge and closing-wedge high tibial osteotomy.

A lot of good outcomes have been reported after opening-wedge high tibial osteotomy (OWHTO) and closing-wedge high tibial osteotomy (CWHTO).The purpose of this study was to examine the rotational alignment after OWHTO and CWHTO performed by the same surgeon in one hospital. The sample included 30 knees from 24 patients. In all cases, the same orthopaedic surgeon performed the osteotomy surgeries using the same method. The tibial external rotation angle (TERA) was measured using the CT images of proximal tibial plateau and distal tibial malleolus from the consecutive axial CT slices of tibia. In this study, two considerations were examined. The first was the change in rotation angle, which was defined by TERA noted before and after the operation. The second was the relationship between the correction angle of the osteotomy and the rotation angle change of the distal tibia. The first was evaluated using the paired-Student's t-test, while the second was analyzed with Pearson's correlation coefficient. In the OWHTO group, the mean TERA was 21.4± 7.0° preoperatively and 20.2 ± 8.0° postoperatively, but no significant difference was seen between pre- and post-operation measurements (p = 0.21). Significant TERA increasing (that is, external rotation of the distal tibia) was seen postoperatively in only three knees. In the CWHTO group, the mean TERA was 19.9 ± 10.5° preoperatively and 16.5 ± 9.5° postoperatively, and significant difference was seen between pre- and post-operative TERA (p < 0.05). No significant correlation was seen between the correction angle and the change of the rotation angle in either group (r = 0.40, r = 0.12) . In the OWHTO group, both internal and external rotation of the distal tibia can occur after surgery. In the CWHTO group, the distal tibia rotated internally postoperatively. No significant correlation was seen between the correction angle and the change in the rotation angle in either group.

Surgical complication and postoperative pulmonary function in patients undergoing tumor surgery with thoracic wall resection.

Postoperative complications of thoracic wall resection include respiratory complications, skin necrosis and infection. The aim of the present study was to examine postoperative complications in patients who required combined thoracic wall resection during the surgical removal of a tumor. The present study included 68 patients; there were 50 patients with lung tumors and 18 patients with musculoskeletal tumors. The clinical factors associated with complications were compared between the two groups. Preoperative and postoperative pulmonary function tests were performed to examine the residual pulmonary function in 16 patients. Thoracic cage reconstruction was performed in 46 patients. Postoperative complications occurred in 30 (44.1%) patients, and one patient died from postoperative pneumonitis. Compared with the pulmonary function preoperative test results, the postoperative results revealed a decrease in the mean vital capacity percentage and an increase in the mean forced expiratory volume within 1 sec as a percent of the forced vital capacity. In patients with lung tumors, pneumonectomy can result in an increased rate of complications following thoracic wall resection. Residual pulmonary function is affected by impaired thoracic cage expansion and removal of the lung. However, the results of the present study demonstrated that these complications can be somewhat stabilized by thoracic wall reconstruction.

Is metatarsus primus elevatus truly observed in hallux rigidus? Radiographic study using mapping methods.

BACKGROUND: Hallux rigidus and metatarsus primus elevatus (MPE) are associated, but their causal relationship remains unknown. Several surgical approaches for treating hallux rigidus are available. We evaluated morphological characteristics of hallux rigidus with different grades to determine the optimal surgical approach. The amount of degenerative change in the metatarsophalangeal joint on the preoperative roentgenograms was graded on a scale of 1-3. We analyzed the morphology of hallux rigidus using X-ray image mapping developed by our team. METHODS: This study involved weight-bearing, dorsoplantar, and lateral foot X-rays of 36 feet from 26 patients underwent surgery for hallux rigidus (Group R) at our institution, and 26 normal feet (Group N). A two-dimensional coordinate system was used to analyze the sharps of these feet by converting each dot on the radiographs into X and Y coordinates. Diagrams of the feet from each group were drawn for comparison. Feet with grades 2 (Group R2) and 3 (Group R3) hallux rigidus and normal feet were compared by Kruskal-Wallis test. RESULTS: Mapping revealed that the tip of distal phalanges of the second, and third toes in Group R medially shifted (P < 0.05) in dorsoplantar image of the feet, and that the medial point, a part of the talus, navicular, cuneiform, and first metatarsal bone in Group R, shifted lower (P < 0.05) in lateral feet images of the feet. Multiple comparisons revealed a significant navicular bone depression in grade 3 hallux rigidus compared with normal feet. A significant difference was observed between Group N and R3 but not between Group R2 and N or R3. CONCLUSIONS: X-ray morphological analysis of the foot revealed MPE in Group R. Elevation gradually increased as hallux rigidus grade worsened. Therefore, osteotomy combined with cheilectomy, whereby the first metatarsal bone can be tilted toward the plantar side, are useful for treating a higher-grade hallux rigidus. LEVEL OF EVIDENCE: Level III, comparative study.

Wrist Swelling in Kienböck's Disease.

Background and Purpose Wrist swelling is a frequent clinical manifestation of Kienböck's disease, but no study has reported the site and pathology of wrist swelling in this disease. The aim of this study is to elucidate the site and pathology of wrist swelling in Kienböck's disease. Materials and Methods Dorsal and palmar soft tissue thicknesses of the wrist were measured on standard lateral radiographs of the wrist in 26 patients with Kienböck's disease and 30 subjects without intra-articular lesion. Axial magnetic resonance imaging (MRI) views were examined to detect the site of swelling. The dorsal capsular ligament in three patients with Kienböck's disease underwent histological examination. Results Radiographic study confirmed dorsal wrist swelling in 24 of 26 (92%) patients examined compared with the contralateral unaffected wrists. MRI demonstrated thickening of the dorsal capsular ligament and extensor layer with synovial proliferation. Histological examination revealed nonspecific chronic inflammation. Conclusion Dorsal wrist swelling in Kienböck's disease is a common manifestation and constitutes a part of pathology of Kienböck's disease, although further study is required to clarify the relation between wrist swelling and etiology of Kienböck's disease. Level of Evidence This is a Level III study.

Sauvé-Kapandji procedure with headless compression screw in patients with rheumatoid arthritis.

OBJECTIVE: We examined the surgical outcomes of the Sauvé-Kapandji (S-K) procedure using a headless compression screw and a metal cancellous screw in patients with rheumatoid arthritis (RA). METHODS: This retrospective study included 41 RA patients who underwent the S-K procedure for distal radioulnar joint disorders with two screws: headless compression screws (HCS group, n = 20) and cannulated cancellous screws (CCS group, n = 21). Clinical and radiographic outcomes were assessed 1 year after surgery. Radiographic outcomes included bony union of the distal radioulnar joint (DRUJ), bone resorption around the screw, a screw back-out, and use of additional K-wire. We investigated any complications related to the screw head. RESULTS: All 20 patients in the HCS group showed bone fusion of the DRUJ. In the CCS group, an asymptomatic non-union was observed in one patient and additional K-wire was needed to stabilize the DRUJ in three patients. No patients complained of any complications related to the screw head in the HCS group, while the CCS group demonstrated the hardware protrusion in two patients who complained of tenderness or discomfort at the screw head. CONCLUSIONS: The use of a headless compression screw in the S-K procedure is useful in patients with RA.

Quantitative assessment of orbital fractures in Asian patients: CT measurement of orbital volume.

Enophthalmos is caused by an increase of orbital volume after blowout fracture and is one of the most critical complications of such fractures, but is often masked by swelling soon after injury. If surgery is performed after swelling resolves, it becomes more difficult to treat enophthalmos because of atrophy and fibrosis. Accordingly, it is important to estimate the severity of enophthalmos soon after injury. We developed a new criterion for determining whether orbital fractures are indicated for surgery in Asian patients using analysis of orbital volume. We retrospectively calculated the orbital volume of patients treated surgically or conservatively and analyzed the correlation between changes of orbital volume and the severity of enophthalmos. Regression analysis of the correlation between enophthalmos and increased orbital volume (y = 0.8x + 0.2; correlation coefficient: 0.92) showed that enophthalmos of 2.0 mm corresponded to an increase in orbital volume of 2.25 cm3. This result is similar to data reported previously for Caucasian patients - enophthalmos of 2.0 mm is a common surgical indication worldwide. Our results suggest that an increase of orbital volume of >2.25 cm3 could be a new criterion for surgical treatment of blowout fractures in Asians.

Acute Compartment Syndrome of Upper Extremities with Tendon Ruptures.

BACKGROUND: It is well known that acute compartment syndrome is associated with fracture of the forearm, while involvement of soft tissue injury including musculotendinous injury remains unclear. The purpose of this study was to evaluate the soft tissue involvement, including musculotendinous ruptures, in acute compartment syndrome of the upper limb. METHODS: We retrospectively enrolled 16 patients who underwent surgical treatment for acute compartment syndrome of the upper extremity. The average age of the patients was 47 years (range, 14 to 79) and the mean follow-up period after the surgery was 15 months (range, 12 to 29). Complications included at least one presentation at the final follow up of sensory disturbances or motor disturbances. We examined the presence of musculotendinous injury mechanism of injury, presence of fracture, the performance of skin grafting, and complications. RESULTS: Mechanism of injury of "caught in a machine" was found in six cases. Three of these patients had musculotendinous ruptures and all muscle tears were revealed by intraoperative findings. No patients had muscle ruptures with other injury mechanisms. Seven out of 16 patients (44%) developed complications at final follow-up. Skin grafting was performed in six patients, and five of these patients developed complications. Only one of the nine patients without complications underwent skin grafting. CONCLUSIONS: In cases of high-energy injuries, the surgeon should suspect the presence of a musculotendinous injury prior to surgery.

Fracture after radiation therapy for femoral metastasis: incidence, timing and clinical features.

We analyzed 428 femoral metastases initially treated with radiotherapy between 2002 and 2011 to clarify the clinical details of post-irradiation fractures of femoral metastasis. Patients included 161 men and 167 women, with a mean age of 62 years. Fracture incidence, fracture site, fracture risk based on X-ray images before radiotherapy, and interval from completion of radiotherapy to fracture occurrence were assessed. In addition, 24 pathological specimens obtained during 27 surgeries for these fractures were examined. Fractures occurred in 7.7% of 428 femoral metastases (total 33: 28 actual fractures and five virtual fractures with progressive pain and bone destruction). The fracture rate was 7.8% in the proximal femur and 1.5% in the shaft (P = 0.001). Fractures occurred a median of 4.4 months after radiotherapy, with 39.4% occurring within 3 months and 63.6% within 6 months. Among femurs with high fracture risk according to Harrington's criteria or Mirels' score, the fracture rate was 13.9% and 11.8%, respectively. Viable tumor cells were detected in all five patients with painful virtual fracture, in 85.7% of femurs with actual fractures that occurred within 3 months, and in only 25.0% of actual fractures occurring after 3 months. Post-irradiation fractures of femoral metastasis most frequently occurred within 3 months after radiotherapy, and were more common in the peritrochanteric area than in the shaft. Radiological evidence of impending fracture did not correlate with a high fracture rate. Actual fractures occurring after more than 3 months were likely caused by post-irradiation fragility of the femur, without viable tumor cells.

Promethazine Hydrochloride Inhibits Ectopic Fat Cell Formation in Skeletal Muscle.

Fatty degeneration of skeletal muscle leads to muscle weakness and loss of function. Preventing fatty degeneration in skeletal muscle is important, but no drug has been used clinically. In this study, we performed drug repositioning using human platelet-derived growth factor receptor α (PDGFRα)-positive mesenchymal progenitors that have been proved to be an origin of ectopic adipocytes in skeletal muscle. We found that promethazine hydrochloride (PH) inhibits adipogenesis in a dose-dependent manner without cell toxicity. PH inhibited expression of adipogenic markers and also suppressed phosphorylation of cAMP response-element binding protein, which was reported to be a primary regulator of adipogenesis. We established a mouse model of tendon rupture with intramuscular fat deposition and confirmed that emerged ectopic adipocytes are derived from PDGFRα+ cells using lineage tracing mice. When these injured mice were treated with PH, formation of ectopic adipocytes was suppressed significantly. Our results show that PH inhibits PDGFRα+ mesenchymal progenitor-dependent ectopic adipogenesis in skeletal muscle and suggest that treatment with PH can be a promising approach to prevent fatty degeneration of skeletal muscle.

Predictors of postoperative outcomes of cubital tunnel syndrome treatments using multiple logistic regression analysis.

BACKGROUND: This retrospective study was designed to investigate prognostic factors for postoperative outcomes for cubital tunnel syndrome (CubTS) using multiple logistic regression analysis with a large number of patients. METHODS: Eighty-three patients with CubTS who underwent surgeries were enrolled. The following potential prognostic factors for disease severity were selected according to previous reports: sex, age, type of surgery, disease duration, body mass index, cervical lesion, presence of diabetes mellitus, Workers' Compensation status, preoperative severity, and preoperative electrodiagnostic testing. Postoperative severity of disease was assessed 2 years after surgery by Messina's criteria which is an outcome measure specifically for CubTS. Bivariate analysis was performed to select candidate prognostic factors for multiple linear regression analyses. Multiple logistic regression analysis was conducted to identify the association between postoperative severity and selected prognostic factors. RESULTS: Both bivariate and multiple linear regression analysis revealed only preoperative severity as an independent risk factor for poor prognosis, while other factors did not show any significant association. CONCLUSIONS: Although conflicting results exist regarding prognosis of CubTS, this study supports evidence from previous studies and concludes early surgical intervention portends the most favorable prognosis.

Factors associated with functional limitations in the daily living activities of Japanese hip osteoarthritis patients.

AIM: As society ages, there is a vast number of elderly people with locomotive syndrome. In this study, the factors associated with functional limitations in daily living activities evaluated by female hip osteoarthritis (OA) patients were investigated. METHODS: This study was a cross-sectional study. The subjects were 353 female patients who were newly diagnosed with hip OA at an orthopedic clinic with no history of hip joint surgery. Outcome indices were functional limitations in two daily living activities obtained from a questionnaire completed by the patients: (i) standing up (standing from a crouched position) and (ii) stair-climbing (climbing and/or descending stairs). The odds ratios (ORs) and 95% confidence intervals (CIs) were computed for explanatory variables using the proportional odds model in logistic regression to evaluate their associations with functional limitations. RESULTS: Functional limitations in standing up were associated with heavy weight (third tertile vs. first tertile: 1.91, 1.11-3.27), participation in sports at school (0.62, 0.40-0.98), parity (vs. nullipara: 1.96, 1.08-3.56), old age and OA stage. Associations with functional limitations in stair-climbing were seen with short height (< 151.0 cm vs. ≥ 156.0 cm: 2.05, 1.02-4.12), bilateral involvement (vs. unilateral: 1.71, 1.01-2.88), old age and OA stage. CONCLUSION: Old age, OA stage, heavy weight, parity, shorter height and bilateral OA were associated with functional limitations in standing up and/or stair-climbing, whereas participation in sports such as club activities in school maintained standing up.

Factors associated with diagnostic stage of hip osteoarthritis due to acetabular dysplasia among Japanese female patients: a cross-sectional study.

BACKGROUND: In Japan, the majority of hip osteoarthritis (OA) was caused by acetabular dysplasia, and about 90 % of patients were female. The present study focused on Japanese female patients with hip OA due to acetabular dysplasia, and examined the associated factors with OA staging at diagnosis, in special reference to body weight. METHODS: Study subjects were 336 Japanese women who were newly diagnosed with hip OA caused by acetabular dysplasia at 15 hospitals in 2008. The self-administered questionnaire elicited patients' body weight at age 20 and at OA diagnosis. Four ranked OA staging according to radiographic findings of the hip joint (pre-OA, initial stage, advanced stage or terminal stage) was regarded as the outcome index. Proportional odds models in logistic regression were used to calculate odds ratios (ORs) and 95 % confidence intervals (CIs) for severer stage of OA. RESULTS: At diagnosis, 45 % of patients suffered from terminal stage of OA, whereas 13 % and 14 % were categorized into pre-OA and initial stage, respectively. After adjustment for potential confounders, weight gain since age 20 revealed the increased ORs for severer OA stage at diagnosis (OR 2.02; 95 % CI, 1.07-3.80). Other significant characteristics were age (67+ vs. 20-49 years, OR 12.4), lower education (junior high school vs. junior college or higher, OR 4.00), parity (OR 2.19), lower acetabular head index (<60.0 vs. 71.1+, OR 2.36), and longer duration since symptom onset (6.0+ vs. <1.0 year, OR 2.94). CONCLUSIONS: Weight gain since age 20 might be involved in mechanisms of OA development, which is independent of age or severity of acetabular dysplasia.

Cigarette Smoking Is Associated With Cubital Tunnel Syndrome.

INTRODUCTION: The aim of this study was to validate the potential association between cigarette smoking and cubital tunnel syndrome (CubTS). METHODS: One hundred patients with CubTS were compared with 100 controls with ulnar abutment syndrome matched for age, gender, and body mass index. The smoking status was compared between patients and controls using the sign test and the Wilcoxon signed rank test. Conditional logistic regression was used to calculate the association between CubTS and pack-years smoked. RESULTS: A significant association was found between increased pack-years smoked and CubTS. A significant difference in the number of never smokers and ever smokers was observed between the patients with CubTS and controls. The difference in mean pack-years in the patients and controls was highly significant. A dose-dependent association with pack-years was found between patients and controls. CONCLUSIONS: High cumulative cigarette smoking is associated with CubTS. Muscle Nerve 54: 1136-1138, 2016.

Pseudoarthrosis of the ilium after periacetabular osteotomy that was treated by cemented total hip arthroplasty: a case report.

BACKGROUND: Preserving the hip joint to delay arthroplasty for patients with acetabular dysplasia-associated early-stage osteoarthritis has become more common, and several surgical procedures have demonstrated pain relief and improved hip joint function. Periacetabular osteotomy, one of the joint-preserving surgical procedures of the hip, provides favorable outcomes, although there are no reports of total hip arthroplasty being used to treat pseudoarthrosis of the periacetabular osteotomy segment. Therefore, we report a case of pseudoarthrosis in the osteotomy segment after periacetabular osteotomy. The patient was treated using modified total hip arthroplasty and achieved a favorable short-term outcome. CASE PRESENTATION: A 62-year-old Japanese woman was diagnosed with bilateral acetabular dysplasia at the age of 50 years, and underwent right and left periacetabular osteotomy at the ages of 52 and 55 years, respectively. When she was 61-years old, she experienced repeated episodes of left coxalgia during walking, with increasing pain at rest, and subsequently visited our department. Plain radiography and computed tomography of her left hip joint confirmed pseudoarthrosis of the periacetabular osteotomy segment. In addition, narrowing of her left hip joint space was observed, which indicated advanced osteoarthritis of the hip. Therefore, she underwent left total hip arthroplasty when she was 62-years old. During the surgery, fibrous fusion of the periacetabular osteotomy segment was confirmed via fluoroscopy, although no abnormal mobility was observed. Thus, the osteotomy segment was fixed with one absorbable screw and two bone pegs (which were prepared using allogeneic bone), and the acetabular cup was fixed using cement. Her postoperative course was generally favorable and bone fusion of the periacetabular osteotomy segment was confirmed at 3 years and 6 months after surgery. Her modified Harris hip score was 43 before the surgery and had improved to 90 at the final follow-up. CONCLUSIONS: Modified total hip arthroplasty was successfully used to treat osteoarthritis of the hip and pseudoarthrosis of the periacetabular osteotomy segment. This procedure achieved pseudoarthrosis region bone fusion and a favorable postoperative outcome.

Cortical bone remodeling in parosteal osteosarcoma mimicking medullary involvement: a case with the difficulty in pre-surgical staging.

Parosteal osteosarcoma (POS) is a low-grade well-differentiated variant of osteosarcoma that affects the metaphyseal surface of a long bone. Although Grade-1 POS sometimes involve the medullary canal, such patients are not at a greater risk of local recurrence or metastases. In this report, we describe a rare case of POS in the right distal femur with an intramedullary sclerotic lesion mimicking medullary involvement caused by secondary remodeling of the underlying cortex of the tumor. A 34-year-old woman complained of having a painful hard mass in her right knee for six months. Imaging studies revealed a broad-based sclerotic mass attached to the cortex of the distal and lateral aspect of the femur, along with an intramedullary lesion. Histopathological examination of a biopsy specimen revealed Grade-1 POS. We diagnosed a medullary involvement and we performed a wide resection, including the intramedullary lesion. Histopathological examination of the resected specimen revealed that the intramedullary lesion only exhibited remodeling of the underlying tumor cortex without tumor cell invasion. To the best of our knowledge, this is the first report of such imaging features and pathological findings in a patient with POS. Our experience with the present patient indicates that good local control and overall prognosis of patients with medullary involvement in Grade-1 POS may be due to the remodeling of the underlying cortex mimicking "medullary involvement." This feature will add to the range of diagnostic difficulty experienced during the preoperative staging of POS.

Relationship of acetabular dysplasia in females with osteoarthritis of the hip to the distance between both anterior superior iliac spines.

BACKGROUND: Acetabular dysplasia (AD) is the main cause of hip osteoarthritis in Japan. A simple method to evaluate acetabular dysplasia would be helpful for early treatment or prevention of hip osteoarthritis. Acetabular dysplasia is reported to be associated with pathological transverse growth of the pelvis, indicating that the distance between the 2 anterior superior iliac spines might be useful for screening and detection of acetabular dysplasia. The purpose of this study was to determine if the acetabular dysplasia radiographic parameters are related to the distance between the 2 anterior superior iliac spines in patients with hip osteoarthritis. MATERIAL AND METHODS: In this study, data obtained in a previous multi-institutional examination of patients with hip osteoarthritis in Japan were evaluated. The anterior superior iliac spine distances of 176 female patients (mean age, 54 years; range, 18-85 years) were measured by physical examination. The relationship between the anterior superior iliac spine distance and acetabular dysplasia was analyzed, and the anterior superior iliac spine distances of the patients with acetabular dysplasia who were at relatively high risk for hip osteoarthritis were compared with that of the patients at lower risk. RESULTS: A statistically significant relationship between the anterior superior iliac spine distance and all of the acetabular dysplasia parameters was observed. The anterior superior iliac spine distances of the acetabular dysplasia patients with a relatively high risk for radiographic acetabular dysplasia parameters were significantly smaller than those of patients at lower risk. Even after adjustment for age, height, and weight, significantly increased relative risk for having high risk AD was found in patients with an ASIS distance of less than 24.5 cm. CONCLUSIONS: There was a significant relationship between the anterior superior iliac spine distance and the degree of acetabular dysplasia.

iTRAQ-based proteomics reveals novel biomarkers of osteoarthritis.

OBJECTIVE: We performed comprehensive proteomic analyses of articular cartilage by using the isobaric tags for relative and absolute quantitation (iTRAQ) method, and searched for candidate biomarkers for osteoarthritis (OA). METHODS: Articular cartilage was collected from patients with OA or femoral neck fracture for the control group. Molecular variations were detected by the iTRAQ method, and quantitative analyses were performed by western blot. RESULTS: Using the iTRAQ method, we identified 76 proteins with different expression levels in OA patients and the control group. Among these proteins, we selected LECT2 (leukocyte cell-derived chemotaxin-2), BAALC (brain and acute leukemia, cytoplasmic), and PRDX6 (peroxiredoxin-6), which had not been reported as biomarkers for OA. CONCLUSIONS: Use of these proteins in combination with conventional OA biomarkers may better reflect the grade and prognosis of OA.