佐粧 孝久

定量的エラストグラフィー(Strain ratio:SR)によるアキレス腱の弾性を計測し、再現性と有効性を検討した。対象は20〜60歳代の正常被験者50名100足である。2名の検者による検者内再現性ICC(1、3)は0.87〜0.93、検者間再現性ICC(2、2)は0.75と良好だった。Bモードによる定性的な腱変性の評価法で、変性がある腱のSR(0.68)は変性がない腱(0.36)と比べて高値であり、腱が軟らかかった(p<0.001)。年代別のSRは、30歳代ではSRが低値で、腱が硬かった。他の年代では差がなかった。SR計測は、アキレス腱変性の定量的評価法として有用な可能性がある。(著者抄録)

Osteoarthritis of the knee joint (KOA) is an important problem to be solved in aged society. Objective assessment of disease progression is mandatory for establishing adequate treatment system. Radiographic examination is a standard method but it is too rough to detect subtle changes occur in limited period. Contrary to this, magnetic resonance imaging (MRI) is expected to work as biomarker as it appears to be keen enough to capture subtle changes. Several MRI-based assessment systems have been developed to assess the status of KOA but they are too complicated and time consuming. Originally developed system, the Irregularity Index System (I-I System) is one of those but the simplest method because it is composed of only one item; i.e., the contour of the femoral condyle. Cross-sectional study revealed good correlation between irregularity of the contour and clinical severity but longitudinal changes are yet to be solved. In this paper longitudinal change of irregularity was determined using publicly available MRI data base concerning KOA. As a result, I-I System could detect changes over average of 14 months and it related to deterioration of clinical knee score.

Objective: Osteoarthritis (OA) leads to pain and loss of function in affected joints. Gait disturbance results from these symptoms of OA, and gait analysis can be important to evaluate the progression of OA. The purpose of this study was to analyze gait pattern in a rodent model of OA and to assess the effects of intra-articular injection of hyaluronan (IAI-HA) by gait analysis, along with histological evaluation. Design: OA was induced by destabilization of the medial meniscus (DMM) of C57BL/6 mice. IAI-HA started 3 weeks after DMM surgery. Mice were allocated to three groups and were given either 800-kDa HA (800-HA), 6000-kDa HA (6000-HA) or saline. We compared these three groups with a sham group by gait analysis using CatWalk (TM). Histological evaluation was performed to assess articular cartilage changes in the knee joints. Results: Mice injected with 800-HA or 6000-HA showed gait patterns similar to that of the sham mice, while the saline-injected group showed gait disturbances 12 and 16 weeks after DMM surgery. Histological changes in articular cartilage were similar among the 800-HA, 6000-HA and saline-treated groups, demonstrating OA progression throughout the experimental time points. Positive gait-related effects of IAI-HA might occur by its pain relieving effect and/or by preventing contracture. Conclusion: IAI-HA prevented gait disturbances in the DMM model, but did not prevent histological changes associated with OA progression. (C) 2014 Published by Elsevier Ltd on behalf of Osteoarthritis Research Society International.

The cause of pain following rotator cuff tear has not been fully elucidated. The purpose of this study was to evaluate behavior and inflammatory cytokines in a rat unstabilized rotator cuff defect (UCD) model. Forty-five Sprague-Dawley rats were divided into three groups: sham; UCD; and stabilized rotator cuff defect (SCD). Gait analysis was examined using CatWalk. Tumor necrosis factor (TNF)-α, interleukin(IL)-1β, and IL-6 were measured within the subacromial bursa and the glenohumeral joint synovium at 21 and 56 days after surgery using an enzyme-linked immunosorbent assay (ELISA). Stride length, print area and contact intensity in the UCD group was significantly lower than in the sham group after surgery. Stride length, print area and contact intensity in the SCD group was significantly higher than in the UCD group. In contrast, TNF-α, IL-1β, and IL-6 in the UCD group was significantly higher than in the sham group at days 21 and 56. However, TNF-α, IL-1β, and IL-6 in the SCD group was significantly lower than in the UCD group at days 21 and 56. The present results suggest that SCD is effective not only in improving shoulder function but also in reducing inflammatory cytokines, which may serve as one source of pain due to rotator cuff tear.

To estimate the long-term possibility of needing surgery on contralateral knees that were asymptomatic at the time of initial discoid lateral menisci (DLM) surgeries, a minimum of 10 years of follow-up was performed after unilateral surgery for a torn DLM. Eligible patients had received arthroscopic meniscectomy between 1986 and 2001 for unilateral torn DLM. Patients with symptomatic contralateral knees at the time of initial surgery were excluded. Among these patients, only those aged no more than 20 years at the time of surgery were included in the study. Ultimately, 30 contralateral knees were followed for an average of 16.6 years after the initial knee surgery. Types of menisci were examined from operative records employing Watanabe's classification. When surgical treatment was necessary on contralateral knee, time interval from initial surgery to the second surgery was recorded. Patients were divided into two groups: those who needed surgical treatment on their contralateral knees (surgery group: S group) and those who did not need surgical treatment on their contralateral knees (non-surgery group: N group). Age at the time of initial surgery, sex, and type of menisci were examined and compared between the two groups. Seven of the 30 knees received arthroscopic surgery during the follow-up period (at an average of 1.6 years after the initial surgery). The rest of the 77% of contralateral knees survived a follow-up period of at least 10 years without requiring surgery. A higher percentage of female patients needed contralateral knee surgeries (30%, 6/20 patients) compared with male patients (10%, 1/10 patients). The possibility for needing surgery on the contralateral knee was highest in the first 2 years and decreased drastically thereafter. Copyright © 2014, Asia Pacific Knee, Arthroscopy and Sports Medicine Society.

The purpose of this study was to evaluate side-to-side differences in three-dimensional clavicle kinematics in normal shoulders during dynamic scapular plane elevation using model-image registration techniques. Twelve healthy males with a mean age of 32 years (range, 27-36 years old) were enrolled in this study. Clavicle rotations were computed with bilateral fluoroscopic images and CT-derived bone models using model-image registration techniques and compared between dominant and nondominant shoulders. There was no difference in retraction between both shoulders. The clavicle in dominant shoulders was less elevated during abduction than in nondominant shoulders (P=0.03). Backward rotation angles of dominant shoulders were significantly smaller than those of nondominant shoulders throughout the activity (P=0.03). Clavicular kinematics during scapular plane abduction were different according to hand-dominance.

人工膝関節のUHMWPEにRF tagを埋め込み、手術時の情報を記録することが可能か検討した。RF tagの長さが30mmの場合の通信感度は-66.2dBm、60mmの場合は-53.4dBm、アンテナが長い方が通信感度が高くなった。リーダライタとRF tagが通信可能な距離は、RF tagの長さが30mmの場合は40mm、60mmの場合は200mmであった。10万回、50万回、100万回繰り返し荷重試験前のRF tagの通信感度は、それぞれ-53.0dBm、-52.4dBm、-52.3dBmであった。繰り返し荷重試験後では、それぞれ-55.6dBm、-55.7dBm、-53.3dBnであった。繰り返し荷重試験前後の通信感度の差が1〜3dBm程度であることや、繰り返し荷重の回数が増加しても感度に顕著な差がみられないことから、荷重を加えたことによる破損はなかったと考えられた。

カーボンナノチューブ含有チタン合金の摺動特性と細胞適合性について検討した。CNT-SP700のmetal on metal摺動部での摩耗特性を評価するために、ピンとディスクをともにCNT-SP700あるいはSP700にしてピンオンディスク型すべり摩耗試験を行った。CNT-SP700の摩耗量はSP700と比較して有意に少なかった。CNT添加による摩耗量への影響は見られなかった。試験後のUHMWPHの表面粗さは、ディスクがSP700では14.59μm、CNT-SP700では13.36μm、Co-α-Moでは15.07μmであった。CNT-SP700とSP700を比較すると、培養1日目には細胞数に差はないが、培養3日目以降ではCNT-SP700で細胞数が有意に多かった。SP700とCNT-SP700の細胞面積およびアスペクト比に有意差はなかった。

MRIを用いた変形性膝関節症(OA)の簡便な半定量的評価法(SMOAK)を開発し、その妥当性と有用性についてOAIのデータを用いて検討を行った。再現性は良好であり、既存の単純X線分類やMRIによる詳細な評価法と矛盾なく評価が可能だった。経時的な関節裂隙の狭小化や症状の進行との相関があり、OAの進行が予測可能であることが示唆された。保存的治療の効果判定や手術などの介入時期の判断に有用であると考える。(著者抄録)

OBJECTIVE: The purpose of this study is to compare the anatomy of rheumatoid hallux valgus with that of idiopathic hallux valgus from the standpoint of joint-preserving surgery. METHODS: One hundred forty-eight feet of 81 rheumatoid patients were included. Feet with idiopathic hallux valgus and normal feet were compared as controls. Weight-bearing dorsoplantar radiographs of the feet were taken of each patient. A two-dimensional coordinate system was defined on the radiographic image, and 19 anatomic points of the forefoot were measured. RESULTS: In rheumatoid hallux valgus, the first metatarsal head shifted medially as hallux valgus angle increased, which was similar to the deformity of idiopathic hallux valgus. Proximal deviation of the tips of the lesser toes, caused by clawing and dislocations of the metatarsophalangeal joints, occurred in rheumatoid hallux valgus. Specifically the tips of the second toes in rheumatoid hallux valgus were located more proximally than those in idiopathic hallux valgus irrespective of the severity of hallux valgus. CONCLUSIONS: Corrective osteotomy of the first metatarsal is a reasonable procedure for rheumatoid hallux valgus. Additionally, correction of the second toe deformity to make a stable lateral support on the hallux may be another important factor for successful joint-preserving surgery.

Background: Cystic mass lesions in the popliteal area, called popliteal cysts or Baker's cysts, are usually minimally symptomatic and not related to intra-articular morbidity in the pediatric population. Although multiple studies have described cases of spontaneous resolution over a period of several months to a few years, others still consider surgical treatment necessary. Furthermore, no previous studies have used magnetic resonance imaging (MRI) to confirm the disappearance of popliteal cysts. In this retrospective study, we reviewed records of patients with popliteal cysts to investigate the natural history of this disease. Methods: The medical records of patients with popliteal cysts followed for at least 12 months were retrospectively reviewed. The patient set comprised of 17 knees in 15 males and 3 knees in 2 females. Mean age was 5.6 +/- 2.0 years (range, 1.8 to 11.4 y) at their initial visit to the clinic, and mean follow-up period was 53.1 +/- 31.6 months (range, 12.6 to 147.8 mo). MRI findings were reviewed for the 16 knees in 13 patients who had undergone MRI. Symptoms and clinical course were extracted from the medical records of all the study subjects and analyzed. Results: Although 6 knees (30%) had histories of pain in the popliteal area, no patient complained of pain at their initial visit. Seventeen cysts (85%) naturally decreased in size or disappeared on clinical examination and/or ultrasound. Cysts confined to either the gastrocnemio-semimembranosus bursa or the subgastrocnemius bursa according to the MRI findings were classified as type I, and cysts which occupied both bursae were classified as type II. Eight knees received MRI examination more than once, and complete disappearance was confirmed in 5 of these knees. All type II cysts converted to type I, and all cysts which completely disappeared were type I before disappearance. Conclusions: The MRI findings in our study population confirmed that popliteal cysts in pediatric populations can be expected to completely resolve in due course without treatment.

Our aim was to clarify the distribution of hip pain in patients with osteoarthritis of the hip secondary to developmental dysplasia of the hip (DDH). We retrospectively studied 443 hips in 369 patients with osteoarthritis secondary to DDH; mean age was 61 years, and follow-up rate was 84 %. Hip pain was defined as preoperative pain that was relieved 3 months after total hip arthroplasty. Distribution of pain originating in the hip was 89 % (393 hips) to the groin, 38 % (170 hips) to the buttock, 33 % (144 hips) to the anterior thigh, 29 % (130 hips) to the knee, 27 % (118 hips) to the greater trochanter, 17 % (76 hips) to the low back, and 8 % (34 hips) to the lower leg. When the groin, buttock, and greater trochanter were combined as the hip region, 95 % (421 hips) of pain was located in the hip region. On the other hand, when the anterior thigh, knee, lower leg, and low back were combined as the referral region, 55 % (242 hips) showed referred pain. We suggest that rheumatologists be aware of hip disease masquerading as knee pain or low back pain.

Objective: To investigate the longitudinal angiogenic activity of subchondral bone and cartilage during the progression of osteoarthritis (OA) using a rabbit model of OA. Materials and methods: OA was surgically induced by anterior cruciate ligament transaction (ACLT) in left knee of 12 months old female New Zealand white rabbits (n = 33). Histological examination, immunohistochemistry, and angiogenic activity assay was done at 0, 2, 4, 6, 8, 12 weeks after ACLT. Histologic evaluation was performed with haematoxylin and eosin, safranin-O staining to assess the OA change of medial femoral condyle (MFC) and lateral femoral condyle (LFC). CD31 immunohistochemistry was performed to confirm the vascular invasion at osteochondral junction. A co-cultured tubule formation assay was conducted to evaluate angiogenic activity of the subchondral bone and cartilage of MFC and LFC as well as synovium. Association between histological changes, angiogenic activity, and vascular invasion were evaluated. Results: OA changes increased in a time-dependent manner both in MFC and LFC. Angiogenic activity of subchondral bone showed a monomodal change during the OA progression, achieved a peak in the early to progressive stage and decreased to normal level in the late stage of OA. Surge of vascular invasion was observed following the increase of angiogenic activity in the progressive stage of OA. Angiogenic activity of cartilage did not change during the course of OA progression. Conclusion: Angiogenic activity of subchondral bone was elevated in the early to progressive stage of OA and vascular invasion into the osteochondral junction followed. (C) 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved,

It is known that free nerve endings are degenerated after application of shock waves. We therefore hypothesized that the application of shock waves to muscle induces dysfunction of neuromuscular transmission at neuromuscular junctions. We investigated changes in neuromuscular transmission in response to shock wave application. Sprague-Dawley rats were used in this study. Two thousand shock waves at an energy flux density of 0.18 mJ/mm(2) were applied to their right calf muscles. Neuromuscular junctions of gastrocnemius muscles were evaluated using rhodamine-α-bungarotoxin on the day of treatment (n  =  5). Amplitude and latency of compound muscle action potentials were measured on the day of treatment and 1, 2, 4, 6, and 8 weeks after treatment (n  =  10, each group). Degenerated acetylcholine receptors existed in all treated muscles. Although the action potential amplitude on the treated side was significantly less than on the control side from the day of treatment (25.1 ± 7.8 vs. 34.5 ± 9.1, p  =  0.012) to 6 weeks (27.9 ± 7.2 vs. 34.5 ± 7.2, p  =  0.037), there was no significant difference at 8 weeks. There was no significant difference in transmission latency between the groups. The application of shock waves to muscle induced a transient dysfunction of nerve conduction at neuromuscular junctions.

Relatively high rates of loosening and implant failure have been reported after total ankle arthroplasty. Abnormal kinematics and incongruency of the articular surface may cause increased contact pressure and rotational torque applied to the implant, leading to loosening and implant failure. We measured in vivo kinematics of two-component total ankle arthroplasty (TNK ankle), and assessed congruency of the articular surface during the stance phase of gait. Eighteen ankles of 15 patients with a mean age of 75±6 years (mean±standard deviation) and follow-up of 44±38 months were enrolled. Lateral fluoroscopic images were taken during the stance phase of gait. 3D-2D model-image registration was performed using the fluoroscopic image and the implant models, and three-dimensional kinematics of the implant and incongruency of the articular surface were determined. The mean ranges of motion were 11.1±4.6°, 0.8±0.4°, and 2.6±1.5° for dorsi-/plantarflexion, inversion/eversion, and internal/external rotation, respectively. At least one type of incongruency of the articular surface occurred in eight of 18 ankles, including anterior hinging in one ankle, medial or lateral lift off in four ankles, and excessive axial rotation in five ankles. Among the four ankles in which lift off occurred during gait, only one ankle showed lift off in the static weightbearing radiograph. Our observations will provide useful data against which kinematics of other implant designs, such as three-component total ankle arthroplasty, can be compared. Our results also showed that evaluation of lift off in the standard weightbearing radiograph may not predict its occurrence during gait. © 2012 Elsevier Ltd.

PURPOSE: Pain from osteoarthritis (OA) is generally classified as nociceptive (inflammatory). Animal models of knee OA have shown that sensory nerve fibers innervating the knee are significantly damaged with destruction of subchondral bone junction, and induce neuropathic pain (NP). Our objective was to examine NP in the knees of OA patients using painDETECT (an NP questionnaire) and to evaluate the relationship between NP, pain intensity, and stage of OA. MATERIALS AND METHODS: Ninety-two knee OA patients were evaluated in this study. Pain scores using Visual Analogue Scales (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), painDETECT, duration of symptoms, severity of OA using the Kellgren-Lawrence (KL) system, and amount of joint fluid were evaluated and compared using a Spearman's correlation coefficient by rank test. RESULTS: Our study identified at least 5.4% of our knee OA patients as likely to have NP and 15.2% as possibly having NP. The painDETECT score was significantly correlated with the VAS and WOMAC pain severity. Compared with the painDETECT score, there was a tendency for positive correlation with the KL grade, and tendency for negative correlation with the existence and amount of joint fluid, but these correlations were not significant. CONCLUSION: PainDETECT scores classified 5.4% of pain from knee OA as NP. NP tended to be seen in patients with less joint fluid and increased KL grade, both of which corresponded to late stages of OA. It is important to consider the existence of NP in the treatment of knee OA pain.