Kentaro Aritomi

CCR 7 Ligands Are Required for Development of Experimental Autoimmune Encephalomyelitis through Generating IL-23-Dependent Th17 Cells

CCL19 and CCL21 are thought to be critical for experimental autoimmune encephalomyelitis (EAE) induction, but their precise role is unknown. We examined the role of these chemokines in inducing EAE. C57BL/6 mice lacking expression of these chemokines (plt/plt mice) or their receptor CCR7 were resistant to EAE induced with myelin oligodendrocyte glycoprotein peptide 35–55 (MOG35–55) and pertussis toxin. However, passive transfer of pathogenic T cells from wild-type mice induced EAE in plt/plt mice, suggesting a defect independent of the role of CCR7 ligands in the migration of immune cells. Examination of draining lymph node (DLN) cells from MOG35–55-immunized plt/plt mice found decreased IL-23 and IL-12 production by plt/plt dendritic cells (DCs) and a concomitant defect in Th17 cell and Th1 cell generation. In contrast, production of the Th17 lineage commitment factors IL-6 and TGF-β were unaffected by loss of CCR7 ligands. The adoptive transfer of in vitro-generated Th17 cells from DLN cells of MOG35–55-immunized plt/plt mice developed EAE in wild-type recipient mice, whereas that of Th1 cells did not. Pathogenic Th17 cell generation was restored in plt/plt DLNs with the addition of exogenous IL-23 or CCL19/CCL21 and could be reversed by inclusion of anti-IL-23 mAb in cultures. Exogenous CCL19/CCL21 induced IL-23p19 expression and IL-23 production by plt/plt or wild-type DCs. Therefore, CCR7 ligands have a novel function in stimulating DCs to produce IL-23 and are important in the IL-23-dependent generation of pathogenic Th17 cells in EAE induction.

Seven Years of Chronological Changes of Serum Chromium Levels After Metasul Metal-On-Metal Total Hip Arthroplasty

Although many authors have reported the serum concentrations of metal ions in patients who had metal-on-metal coupling prostheses, most of the studies were not longitudinal, and the follow-up periods were short. We evaluated the longitudinal changes of serum chromium levels in 44 patients who had undergone unilateral metal-on-metal total hip arthroplasty for a minimum of 7 years postoperatively. Although there was a consistent increase in the mean serum chromium level until 3 years after implantation, there was little difference in the levels from years 3 to 7 postoperatively. Although the serum chromium concentration was low throughout postoperative follow-up for 7 years in about 25% of patients, the serum chromium level stayed high or showed gradual elevation in 16.3% of our patients.

Altered antibody production and helper T cell function in mice lacking chemokines CCL19 and CCL21-Ser

The roles of chemokines CCL19 and CCL21 in Ab production were investigated using plt mutant mice, which lack expression of CCL19 and CCL21‐ser in their lymphoid organs. In these mice, the Th response has been shown to tend towards the Th1 type because of accumulation of inflammatory dendritic cells. When plt mice were immunized with 100 μg OVA in CFA, the number of Ab‐forming cells in the draining LN, and serum concentrations of OVA‐specific IgM and IgG Ab, were very close to those of the control, yet IgG2a Ab in plt mice was increased. In vitro IFN‐γ production by the draining LN cells of plt mice was increased. In addition, the ability of helper T cells from plt mice to stimulate Ab production in vitro was prolonged. Also, in the plt mice, in vivo challenge with OVA in incomplete Freunds adjuvant elicited a stronger IgG2a response and a weaker IgG1 response, which is suggestive of a Th1‐dominant response. Similar findings were obtained when mice were immunized with 100 μg OVA in alum, except that with alum the increases observed in plt mice were IgG1 produced in vivo and IL‐4 produced in vitro by draining LN cells. Furthermore, immunization with alum adjuvant also induced a prolonged in vitro recall response of IFN‐γ and IL‐4. These findings indicate that plt mice mount an anti‐OVA Ab response, and suggest that CCL19 and CCL21 induce prompt Ab responses to antigen, and negatively regulate helper T cell responses in vivo.

Original methods to move femoral head medially and caudally after rotational acetabular osteotomy: especially to use ceramic spacer

The operative procedures chosen to treat arthrosis in patients with severe acetabular dysplasia vary among orthopaedic surgeons, particularly in younger patients. We operated on 450 hips with acetabular dysplasia by using the rotational acetabular osteotomy (RAO) method of Ninomiya and Tagawa by Ninomiya (Clin Orthop 247:127–137, 1989). In this report, we describe our technique of performing RAO with hydroxyapatite tricalcium phosphate-composite (HAP-TCP) blocks to achieve good acetabular coverage and the results of this procedure in 16 hips with severe dysplasia, including nine with advanced arthrosis. Adequate coverage of the osteotomized acetabulum was maintained and symptoms, especially pain, showed marked improvement at the latest follow up.

A survey of extensor pollicis longus tendon injury at the time of distal radius fractures

BACKGROUND The purpose of this study is to investigate the presence or absence, incidence, and degree of extensor pollicis longus (EPL) tendon injury by visual confirmation of the EPL at the time of osteosynthesis for distal radius fractures. METHODS The subjects were 25 patients (5 males and 20 females; mean age: 56 years) with distal radius fracture that had a dorsal roof fragment. During osteosynthesis using a volar locking plate, the third compartment was exposed in order to determine the EPL injury. The survey items in this study were: incidences of the forms of EPL injury (1: absent, 2: tendon floor fibrillation, and 3: laceration), and the presence or absence of periosteal rupture on the EPL tendon floor. In addition, on the final follow-up, the presence or absence of EPL rupture, the range of wrist motion, grip strength, Visual Analog Scale (VAS) score, Quick Disabilities of the Arm, Shoulder and Hand (Q-DASH) score, and the Mayo wrist score were investigated. RESULTS During the operation, EPL injury was classified as: 1) absent (12%), 2) tendon floor fibrillation (52%), or 3) laceration (36%). In the EPL tendon floor, periosteal rupture was observed in all patients. The mean postoperative follow-up period was 8 months (6-12 months) and no EPL rupture was observed in any patient. The wrist range of motion was 71° for flexion, 75° for extension, 84° for pronation, and 85° for supination, and the grip (% compared with the unaffected side) was 79%. The VAS, Q-DASH and Mayo scores were 1, 10 and 93 respectively. CONCLUSION This study showed a high incidence of EPL tendon injury at the time of distal radius fractures (88%). To improve the ambient environment of the damaged tendon may be useful in terms of the prevention of tendon injury.

Pedicle freezing with liquid nitrogen for malignant bone tumour in the radius: a new technique of osteotomy of the ulna

We describe a new technique of pedicle freezing of the distal radius with malignant bone tumour and osteotomy of the normal ulna. The distal radius was sufficiently elevated to enable freezing without damaging adjacent tissues by releasing the distal radio-ulnar and radio-carpal joint and cutting the middle third of the ulna. The distal radius (including the tumour) was soaked in liquid nitrogen and the defect filled with iliac grafts. The ulna was repaired with plate and screws and was united at month 2. There was no local recurrence and the postoperative function score was 93%. This technique decreases the risk of non-union of the osteotomy site of the tumorous bone.

Rotational acetabular osteotomy for osteonecrosis of the femoral head after intracapsular fracture of the neck of the femur.

The treatment of osteonecrosis of the femoral head in younger patients varies among orthopaedic surgeons. In particular, the optimal treatment of extensive osteonecrosis associated with femoral head collapse remains controversial. Since 1995, we have performed rotational acetabular osteotomy on 70 hips, including those of 3 patients with extensive osteonecrosis of the femoral head after intracapsular fracture of the neck of the femur. In all 3 patients, adequate coverage of the femoral head by the osteotomized acetabulum was obtained, and their symptoms (especially pain) showed marked improvement at latest follow-up.

Forearm nonunion caused by hyperparathyroidism with 7 years follow up: A case report

Highlights • We report a patient who developed nonunion of both bones of the forearm associated with hyperparathyroidism.• It is necessary to perform close examination to investigate primary disease causing insufficiency fracture.• For treatment of nonunion of the 2 forearm bones, osteosynthesis of the ulna alone achieved sufficient osteal support.

Assessment of dorsal instability of the ulnar head in the distal radioulnar joint: comparison between normal wrist joints and cases of ruptured extensor tendons

In the present study, the adaptability of the distal radioulnar joint (DRUJ) was evaluated using conventional computed tomography (CT) evaluation methods. In addition, we investigated/compared a new method to evaluate dorsal displacement of the ulnar head. Our subjects consisted of 32 healthy volunteers (64 wrists) and 11 patients (13 wrists) with extensor tendon injuries related to dorsal displacement of the ulnar head. To diagnose instability in the DRUJ based on CT scans, the radioulnar line method and the modified radioulnar line method were measured. Instability was evaluated by the new method that the ulnar head was located on the dorsal side from a line involving the peak of Lister’s tubercle in parallel to this baseline was regarded as showing abnormal dorsal displacement of the ulnar head. The diagnostic accuracy of each method was calculated. The sensitivities, specificities, false-positive rates, positive predictive values and the negative predictive value of new methods were better than other two methods. The new method that we recommend is simple. Based on the results of this study, an evaluation of normal/abnormal dorsal displacement of the ulnar head in the DRUJ using the new method may be useful for determining the timing of surgery.

Devising for a distal radius fracture fixation focus on the intra-articular volar dislocated fragment

Introduction Distal radius fracture (DRF) accompanied by intra-articular volar displaced fragment is difficult to reduce. This volar fragment remains when treated with a simple buttress effect alone, and V-shaped deformity may remain on the articular surface. We attempted to improve dorsal rotational deviation of volar fragment by osteosynthesis applying the condylar stabilizing technique. We report the surgical procedure and results. Materials and methods The subjects were 10 cases of DRF accompanied by intra-articular volar displaced fragments surgically treated (mean age: 69 years old). The fracture type based on the AO classification was B3 in 1 case, C1 in 4, C2 in 2, and C3 in 3 cases. All cases were treated with a volar locking plate. Reduction was applied utilizing the angle stability of the volar locking plate, similarly to the condylar stabilizing technique. On the final follow-up, we evaluated clinical and radiologic evaluation. To evaluate V-shaped valley deformity of the articular surface, the depth of the lunate fossa of the radius was measured using computed tomography (CT). Results The duration of postoperative follow-up was 11 (6–24) months. Mayo wrist score was 93 (Excellent in 10 cases). No general complication associated with a volar locking plate was noted in any case. Volar tilt on radiography were 11° (4–14). The depth of the lunate fossa on CT was 3.9 ± 0.7 mm in the patients. Conclusion This procedure may be useful for osteosynthesis of distal radius fracture accompanied by intra-articular volar displaced fragments.