Kenji Endo

The Most Effective Exercise for Strengthening the Supraspinatus Muscle Evaluation by Magnetic Resonance Imaging

Background Electromyography has been used to determine the best exercise for strengthening the supraspinatus muscle, but conflicting results have been reported. Magnetic resonance imaging T2 relaxation time appears to be more accurate in determining muscle activation. Purpose To determine the best exercises for strengthening the supraspinatus muscle. Study Design Criterion standard. Methods Six male volunteers performed three exercises: the empty can, the full can, and horizontal abduction. Immediately before and after each exercise, magnetic resonance imaging examinations were performed and changes in relaxation time for the subscapularis, supraspinatus, infraspinatus, teres minor, and deltoid muscles were recorded. Results The supraspinatus muscle had the greatest change among the studied muscles in relaxation time for the empty can (10.5 ms) and full can (10.5 ms) exercises. After the horizontal abduction exercise the change in relaxation time for the supraspinatus muscle (3.6 ms) was significantly smaller than that for the posterior deltoid muscle (11.5 ms) and not significantly different from that of the other muscles studied. Conclusion The empty can and full can exercises were most effective in activating the supraspinatus muscle.

Acral myxoinflammatory fibroblastic sarcoma: a report of five cases and review of the literature

Abstract. Five cases of acral myxoinflammatory fibroblastic sarcoma that occurred in the distal extremities within the subcutaneous tissue are described. In one case, recurrence and metastases were recognized rather rapidly, only 3xa0months after the first excision. There have been no reports of early recurrence or metastases, especially the latter. The predominant type of constituent cells, cellularity of the neoplastic cells and density of inflammatory cells varied microscopically among cases. However, characteristic ganglion-like cells, Reed-Sternberg-like cells, round mononuclear cells and myxoid stroma, sometimes only seen focally, were found in all cases. Positive immunoreaction for vimentin was present in all cases. There was no correlation between positivity of MIB-1 or p53 for the primary tumor and presence of recurrence or metastases. In conclusion, we should be more cautious about the possibility of recurrence or metastases in earlier phases of acral myxoinflammatory fibroblastic sarcoma. Identification of the atypical bizarre fibroblastic component as the manifestation of the malignant nature of this lesion is vital to correct diagnosis, and it is important to attend to the myxoid and hyalinized zones, the inflammatory infiltrate, the presence of ganglion-like cells and acral location as features of acral myxoinflammatory fibroblastic sarcoma.

Cyclooxygenase-2 inhibitor delays fracture healing in rats

Background Cyclooxigenase-2 (COX-2) inhibitors have been reported to delay fracture healing. To investigate the major inhibitory period of COX-2 inhibitors in fracture healing, we administrated etodolac, a COX-2-specific inhibitor, to a rat fracture model by altering the period of administration from early to late. Method After closed fractures had been created at the middle of the femoral shafts in 12-week-old Wister rats, a standardized dose of etodolac was administrated in three ways: group I received it for 3 weeks, group II for just the first week after operation, and group III for just the third (final) week. Group IV was the vehicle control group. Bone maturation was estimated by radiographic scoring system, and mechanically by a three-point bending test. Results and interpretation In both the radiographic and mechanical studies, groups I and II showed lower scores than group IV, indicating that even a short period of administration of a COX-2-specific inhibitor in the early phase of fracture healing creates a risk of delayed healing. ▪

Total sagittal spinal alignment in patients with lumbar canal stenosis accompanied by intermittent claudication.

Study Design. Cross-sectional study of total sagittal spinal alignment in lumbar spinal canal stenosis (LCS) patients with and without intermittent claudication. Objective. To evaluate total sagittal spinal alignment in LCS. Summary of Background Data. The sagittal spinal alignment is an important factor in the management of lumbar degenerative diseases and lower back pain. Patients with LCS accompanied by intermittent claudication adopt a forward-bending posture during walking. However, few studies have quantitatively assessed the abnormal posture in LCS in relation to clinical symptoms. Methods. This study analyzed 93 patients with LCS. They were divided into two groups according to the presence of neurogenic intermittent claudication; patients of the Claudicant group had intermittent claudication of the cauda equina (n = 53; mean age, 66.7) and those of the Nerve root group had no claudication (n = 40; mean age, 67.0). The following parameters were measured on the lateral whole-spine standing radiographs: the distance between the C7 plumb line and the posterior superior corner on the superior margin of S1 (sagittal vertical axis), the angle between the superior margin of the first lumbar vertebra and the first sacral vertebra (L1S1), lumbar lordotic angle, pelvic tilting angle (PA), and pelvic morphologic angle (PRS1). Results. The sagittal vertical axis of the Claudicant group (57.6 ± 37.5 mm) was significantly larger than that of the Nerve root group (40.3 ± 42.3 mm) and was larger in both groups compared with the standard values. Lumbar lordotic angle was smaller (18.8° ± 13.2°) and pelvic tilting angle was larger (27.2° ± 8.3°) in patients with the Claudicant group than those with the Nerve root group (22.4° ± 14.0° and 22.7° ± 7.2°, respectively). Conclusion. Patients of the Claudicant group exhibited forward bending of the trunk and pelvis backtilt, compared with those of the Nerve root group.

Three Successive Stress Fractures at the Same Vertebral Level in an Adolescent Baseball Player

Stress fractures can occur in almost any bone in the body. Most of the lumbar spine stress fractures reported in athletes have occurred at the pars interarticularis. Stress fracture in this area is referred to as spondylolysis. Stress fractures of the pedicle, known as “pediculolysis,” have been known to occur on the contralateral side of a vertebra in which there is also unilateral spondylolysis. Stress fracture of the lamina, known as laminolysis, has been infrequently reported in the literature. In this report, we describe the case of a 17-year-old baseball player who developed three successive stress fractures at the same vertebral level: the first at the left pars interarticularis, the second at the right pedicle, and the third at the right pars interarticularis.

Cervical Vertigo After Hair Shampoo Treatment at a Hairdressing Salon : A Case Report

STUDY DESIGNnA case report of cervical vertigo that occurred after shampoo treatment in a hairdressing salon. Abnormalities were detected on magnetic resonance images and magnetic resonance angiography scans.nnnOBJECTIVESnTo describe the diagnosis of cervical vertigo caused by neck hyperextension.nnnSUMMARY OF BACKGROUND DATAnNeck hyperextension may induce vertigo and dizziness; the pathophysiology remains unclear, however, because subjective findings are usually difficult to document.nnnMETHODSnThe diagnosis, treatment, and outcome of a patient with cervical vertigo that occurred after hair shampoo treatment in a hair dressing salon were assessed.nnnRESULTSnMagnetic resonance angiography demonstrated narrowing of the left vertebral artery, whereas magnetic resonance imaging showed cerebellar infarction. Treatment included rest and drugs that activate cerebral circulation and prevent platelet aggregation. Improvement was noted within few days.nnnCONCLUSIONSnThe authors suggest that the hyperextended neck position during hair shampoo treatment in a beauty parlor may be a risk factor for back lifting or cerebellum vascular insufficiency. Public education should lead to avoidance of this position during hair shampoo treatment at hair dressing salons.

Regulation of nerve growth factor by anti-inflammatory drugs, a steroid, and a selective cyclooxygenase 2 inhibitor in human intervertebral disc cells stimulated with interleukin-1.

Study Design. Regulation of nerve growth factor (NGF) by 2 different anti-inflammatory drugs was investigated in vitro using isolated human intervertebral disc (IVD) cells stimulated with the proinflammatory cytokine interleukin-1 (IL-1). Objective. To investigate the regulation of NGF by a synthetic steroid and a selective cyclooxygenase-2 (COX-2) inhibitor and to clarify the biological role of prostaglandin E2 (PGE2) in this process. Summary of Background Data. NGF is known to play an important role in pain, including low back pain, and to be induced by proinflammatory cytokines in IVD cells. However, the effect of clinically used drugs for managing low back pain on the regulation of NGF is unclear. Methods. Isolated human IVD cells were stimulated with interleukin-1 (IL-1) in the presence or absence of dexamethasone or a selective COX-2 inhibitor (NS-398). NGF expression and release were determined by real-time polymerase chain reaction and enzyme-linked immuno sorbent assay, respectively. Inhibition of PGE2 release was determined by enzyme-linked immuno sorbent assay. The effects of exogenous PGE2 and its receptor (E-series prostanoid receptors [EPs] 1–4) agonists were also tested for NGF regulation. Results. IL-1 transiently induced, in a dose-dependent manner, the induction of NGF in human IVD cells. Pretreatment with dexamethasone strongly inhibited the NGF expression, whereas NS-398 significantly enhanced it at the concentration at which PGE2 release was substantially inhibited. Exogenous PGE2 inhibited IL-1 induction of NGF and this effect was mimicked when EP2 and EP4, but not EP1 and EP3, agonists were supplemented to the culture. Conclusion. Although selective COX-2 inhibitors have been shown to be effective for acute low back pain by inhibiting PGE2 release, our findings suggest that it may have a limited efficacy because it exaggerated NGF expression, whereas dexamethasone inhibited it. On the other hand, PGE2 had an inhibitory function for NGF induction by mediating EP2/4 in human IVD cells. Further studies are needed to clarify whether these observations could take place in vivo. Level of Evidence: N/A

Locally Administered Zoledronic Acid Therapy for Giant Cell Tumor of Bone

Giant cell tumor of bone is locally aggressive and occurs in the meta-epiphyseal region of long bones. Because of its high recurrence rate, local adjuvant therapies such as phenol or liquid nitrogen have been recommended. In the present study, zoledronic acid, a nitrogen-containing bisphosphonate, was administered locally as an adjuvant during a biopsy. An otherwise healthy 43-year-old man presented with pain and swelling in the right knee. Plain radiographs showed an osteolytic lesion of the right proximal tibia. An open biopsy was performed and the intraoperative pathologic diagnosis was giant cell tumor of bone. Following biopsy, the defect was filled with betatricalcium phosphate, and 4 mg of zoledronic acid was locally administered into the tumor lesion. Two months after the biopsy, curettage and bone grafting were performed. Sections were obtained during the curettage for histology to evaluate the response to bisphosphonate treatment. Histologic examination revealed massive tumor cell death in the lesion in which both stromal cells and osteoclast-like giant cells were necrotic. Curettage was performed and the defect was filled with a commercial preshaped hydroxyapatitetricalcium phosphate bone substitute. Eighteen months after curettage, the patient had regained full range of motion and good function of the knee, and radiographs at 18 months after curettage revealed no recurrence of giant cell tumor of bone.

Intrapatellar tendon lipoma with chondro-osseous differentiation: detection of HMGA2-LPP fusion gene transcript

A 54 year old man developed an unusual lipoma in the patellar tendon, consisting of a fibro-adipose component and a chondro-osseous component. The fibro-adipose component contained mature adipocytes, lipoblasts, and fibroblasts; the chondro-osseous component showed typical endochondral bone formation. Molecular analysis showed that the identical HMGA2-LPP fusion transcript—characteristic of lipoma, parosteal lipoma, and pulmonary chondroid hamartoma—was detectable in the both components.

Radiographic Determination of Hip Rotation Center and Femoral Offset in Japanese Adults: A Preliminary Investigation toward the Preoperative Implications in Total Hip Arthroplasty

The values of hip rotation center (HRC) and femoral offset (FO) evaluated according to Caucasian anatomical landmarks have been regarded as a useful reference also for Japanese patients in total hip arthroplasty (THA). In a strict sense, however, since there can be racial differences among their anatomical morphologies, it is clinically important to reconsider those parameters for the Japanese. In the present study, in order to investigate correlations among hip and pelvic morphometric parameters, frontal radiographs were taken from 98 Japanese adults (60 males and 38 females) without acetabular dysplasia and arthropathy in the standing position. Their mean age was 62.0 ± 16.7 years. The horizontal position of HRC was significantly correlated with the pelvic width in both genders (P = 0.0026 and 0.0010 for the males and the females, resp.). The vertical position of HRC was significantly correlated with the teardrop-sacroiliac distance in the males (P = 0.0003) and with the pelvic cavity height in the females (P = 0.0067). However, in both genders, there were no correlations among FO and the other parameters analyzed in this study. Our present findings might contribute to theoretical implications of an appropriate HRC position for Japanese OA patients in THA.