Changes in sagittal spino-pelvic alignment after total hip arthroplasty using the Roussouly classification

Pelvic inclination changes after total hip arthroplasty; we determined how sagittal spino-pelvic alignment changed after total hip arthroplasty. We investigated the change in Roussouly classification type and sagittal spino-pelvic alignment after total hip arthroplasty. Sagittal spino-pelvic alignment was investigated in 135 patients who underwent total hip arthroplasty. Prior to surgery, there were 50 cases (37%) of Type 1 and 2, 53 cases (39.3%) of Type 3, and 32 cases (23.7%) of Type 4. Since none of the Type 1 and 2 cases showed postoperative changes, we divided the Type 3 and Type 4 cases into 3 groups. Cases with pelvic retroversion and reduced lumbar lordosis before total hip arthroplasty showed no change. Half of the cases with satisfactory preoperative sagittal spino-pelvic alignment (SSPA) remained Type 3 with lumbar lordosis even after surgery. However, even in satisfactory Type 3 cases, if there was pelvic retroversion after total hip arthroplasty (THA) surgery, they were reclassified as Type 1 or 2 due to reduced lumbar lordosis and changes in SSPA. Cases of Type 4 with preoperative pelvic anteversion were reclassified as Type 3 after surgery due to a major reduction in the sacral slope angle and changes in SSPA

Expression of osteonectin in articular cartilage of osteoarthritic knees

The expression of osteonectin (ON) in osteoarthritic articular cartilage was investigated by enzyme immunohistochemistry and colloidal gold immunoelectron microscopy. A total of 96 specimens from 9 knees of 8 patients with osteoarthritis (OA) were examined. In OA cartilage, ON-positive cells varied in distribution and were not seen in all the specimens obtained from the same patient. However, in over half of the specimens (56 of 96), especially in the specimens of Mankin's grades from 4 to 9, which corresponds to relatively early stages of OA, ON was expressed in the cartilage above the calcified layer. On the other hand, ON was detected only in the calcified layer below the tidemark in normal articular cartilage. In addition, colloidal gold immunoelectron microscopy revealed ON in chondrocytes and matrix vesicles (MVs). These findings suggest that ON acts through MVs in the early stages of OA as a significant pathogenetic factor involved in intracartilage calcification, which is known to have a close relationship to the progression of OA.</p

Endoscopic carpal tunnel pressure measurement: a reliable technique for complete release

Carpal tunnel syndrome is diagnosed by clinical symptoms, Tinel's sign, Phalen's test and electromyography. Carpal tunnel pressure measurement can also aid in the precise identification of excessive pressure sites that indicate locations for release. In this study, pressure measurements made during endoscopic carpal tunnel release at 5 points were significantly higher anywhere in the carpal tunnel than outside the tunnel and decreased markedly after release. We concluded that our measurement technique can improve the reliability of endoscopic carpal tunnel release by decreasing the likelihood of missing any nerve entrapment sites.</p

Screwless Cup 摺動部の接触面圧力の力学的解析

セメントレスTHA において安定したスクリューレスCup の初期固定を得るには，高い回旋開始時トルク値で初期固定力を確保し，高範囲かつ適切な接触領域の分布を示すことが重要と考える．これまでCup の接触面積がどの程度減少してしまうと，固定力に影響するか力学試験解析した報告は少ない．Cup 摺動部の接触領域を変化させ，実際のヒト寛骨臼の硬さを想定したボーンモデルを作製しフィンの有無が与える影響について力学試験を行った．Cup の辺縁全周が接触するように1mm のアンダーリーミングを行った後に，臼蓋形成不全による骨欠損の有無の影響を考慮し，Cup が臼蓋縁よりはみ出すように骨モデルを10°，20°，30°，40°の角度をつけてカットした骨欠損モデルと，術中の臼蓋に対し再リーミングを想定し1，2，3，6，9mm 偏心したモデルにおいて検討した．骨欠損モデルでは接触面積が10°：94.4%，20°：88.9％，30°：83.3%，40°：78.6％と小さくなり，偏心モデルにおいては1mm：60.4%，2mm：56.7%，3mm：56.2%，6mm：57.8%，9mm：60.4% と6mm 以上の偏心で接触面積は再増加した．最大トルク値では，フィン有りは0°：60.1N/m，10°：58.8N/m，20°：50.2N/m，30°：25.3N/m, 40°：17.4N/m．フィン無しは0°：46.2N/m，10°：40.4N/m，20°：23.5N/m，30°：13.9N/m，40°：7.4N/m であった．フィンの有無に関わらず30°で回旋トルクが著明に低下していた．力学試験においては30°以上において回旋トルク値が極端に低下した．偏心モデルでは2mm 以上で回旋トルクが極端に低下した．結論として，骨との接触面積が減少し，さらにはフィンの掛かりが減少したことが，回旋力低下の要因に大きく影響した．In order to achieve stable initial fixation of a screwless cup in cementless total hip arthroplasty (THA), the initial fixation strength has to be assured at a high torque value on initial rotation, and demonstrating a high range and an appropriate contact area distribution is considered important. To date, there have been few reports discussing the quantitative analysis of how much the contact surface area of the cup has to decrease before the fixation strength of a press-fit cup is affected.In the present study, the contact surface area of the sliding portion of the cup was varied, and this contact surface area was varied in order to conduct comparison testing of mechanical properties, to see whether there was any impact caused by the presence or absence of fins. Bone models were prepared presuming the hardness of actual human acetabula, and their mechanical properties were tested. After performing 1-mm underreaming so that the entire rim of the cup was in contact, taking into consideration possible effects from the presence or absence of bone defects caused by acetabular aplasia, bone defect models were cut so that the cup protruded beyond the rim of the acetabular cartridge and angles of 10 °, 20 °, 30 ° and 40° were created, and, presuming re-reaming with respect to the acetabula during surgery, models with 1-, 2-, 3-, 6-, and 9-mm eccentricity were tested. With the bone defect models, the contact surface area decreased (10°, 94.4%; 20°, 88.9%; 30°, 83.3% and 40°, 78.6%), while in the eccentricity models, the contact surface area increased again at eccentricities of 6 mm or more (1mm, 60.4%;2mm, 56.7%; 3 mm, 56.2%; 6 mm, 57.8%; and 9 mm, 60.4%). In the models with fins, the maximum torque values were as follows: 0°, 60.1 N/m; 10°, 58.8 N/m; 20°, 50.2 N/m; 30°, 25.3 N/m and 40°, 17.4N/m. In the models without fins, the values were as follows: 0°, 46.2 N/m; 10°, 40.4 N/m; 20°, 23.5 N/m; 30°, 13.9 N/m and 40°, 7.4N/m. There was an extreme decrease in the rotational torque value at 30 ° or more, compared to that at 20 °. In models in which eccentricity was applied, at 2 mm or more, when it is difficult for the fins to engage, there was an extreme decrease in the rotational torque. In conclusion, the decrease in the contact surface area between the cup and bone and the reduced engagement of the fins strongly affected the decrease in rotational force

Hospital and clinic cooperation for the treatment of rheumatoid arthritis in Okayama Prefecture, Japan

Objective: To survey the current status and problems of cooperation between clinics and hospitals in Okayama Prefecture, Japan for the treatment of rheumatoid arthritis (RA). 　Methods: We distributed a questionnaire to 300 of the 983 Okayama Prefecture clinics that had either an internal medicine or orthopedic surgery department, from December 2013 to February 2014. The questionnaire covered practice pattern for RA treatment in clinics, current status of the hospital and clinic cooperation, and acceptance of the biologic therapy. 　Results: One hundred clinics responded to the questionnaire. Seventy percent of the clinics reported making referrals to rheumatologists before the initiation of RA treatment, and half of the other 30% of the clinics administered methotrexate as the first-line treatment for RA by their own decision. Sixty-six clinics cooperated with flagship hospitals, conducting medical and laboratory examinations, providing prescriptions, and treating common diseases of patients. These clinics expected the cooperating rheumatologists to follow-up patients every 3 to 6 months and to make the diagnosis, make decisions regarding RA treatment changes, and perform surgery. Seventy-one percent of the clinics responded that cooperation with a hospital is possible even for patients who are administered biologics. As reasons for no cooperation with the flagship hospitals, clinics noted the lack of information about rheumatologists in the area and recent trends in the management of RA. 　Conclusion: The current study reported, for the first time, the actual conditions of management of RA in clinics, as well as future problems of hospital and clinic cooperation in Okayama Prefecture

Impact of Bottom-Sediment Removal on ¹³⁷Cs Contamination in an Urban Pond

Many irrigation ponds in Fukushima Prefecture were decontaminated due to the contamination of radiocesium released from Fukushima Daiichi Nuclear Power Plant. To evaluate the impact of decontamination on 137Cs dynamics in an urban pond in Koriyama City, Fukushima Prefecture, Japan, temporal changes in 137Cs concentrations in bottom sediments and pond water were investigated before and after bottom-sediment removal. Post-decontamination, 137Cs inventories in bottom sediments decreased by 46–89%. 137Cs inventories in bottom sediments were relatively high in fine sediments before decontamination, and were also high at points near the water inlet after decontamination. Following decontamination, the mean 137Cs concentration in suspended solids (SS) and the mean dissolved 137Cs concentration in pond water decreased by 52% and 5%, respectively. Even after decontamination, the normalized 137Cs concentrations in SS and in water, which were calculated by dividing the 137Cs concentrations by the mean 137Cs inventories in each area, were higher than those in rivers, dam reservoirs, and ponds elsewhere in Fukushima. The positive correlations between δ15N values, an indicator of the source contribution to bottom sediments, and 137Cs concentrations in the upper 5 cm of bottom sediments after decontamination implied that SS from urban areas gradually increased the 137Cs inventories in the pond. The results underline the importance of secondary inputs of 137Cs from highly urbanized catchments

Changes in sagittal spino-pelvic alignment after total hip arthroplasty using the Roussouly classification

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