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Kyoji Okada

Publications and source records attributed to Kyoji Okada.

At least 19 recordsLinked to original sources
PubMed2007

Clinical relevance of pathological grades of malignant peripheral nerve sheath tumor: a multi-institution TMTS study of 56 cases in Northern Japan.

BACKGROUND: Malignant peripheral nerve sheath tumor (MPNST) is a relatively rare soft tissue tumor, and its clinical relevance of pathological grades remains obscure. METHODS: Fifty-six cases of MPNST identified from the files of seven oncology centers of the Tohoku Musculoskeletal Tumor Society (TMTS) and National Cancer Center were analyzed for histologic grades, demographics, treatments, and prognostic factors. The average follow-up period was 41 months. RESULTS: Twenty-two men and 34 women with a mean age of 45 years were involved. Forty-four (78.6%) of 56 tumors were in the lower extremity or trunk. Fifty tumors (89%) were classified as high grade, and the remaining six as low grade. Twenty-one (39.6%) of 53 patients who underwent tumor excision developed local recurrences. An axial site and inadequate surgical margin were defined as risk factors for local recurrence. The overall survival rates of the 56 patients were 55.1% at 3 years and 43.3% at 5 years. Univariate analysis of the 56 patients revealed large-sized tumors, metastasis at presentation, and histologically high grade were significantly associated with poor prognosis. Multivariate analysis revealed a large tumor and metastasis at presentation to be independent prognostic factors. CONCLUSIONS: The current study involving 56 patients with MPNST showed the aggressive clinical behavior of the tumor. Large-sized tumors, metastasis at presentation, and high histological grade were related to poor prognosis on univariate analysis, but independency of histological grade was still obscure. In the treatment for a large and high-grade MPNST, an alternative strategy should be further considered.

Adolescent↗
PubMed2006

Tuberculous bicipitoradial bursitis: a case report.

An 76-year-old man with an indolent soft tissue mass on the volar aspect of the left elbow was referred to our institution with a diagnosis of a soft tissue tumor. He had a history of lung tuberculosis since the age of 30. The mass was adjacent to the biceps brachi tendon. It demonstrated homogeneous low-signal intensity on T1-weighted magnetic resonance (MR) images and heterogeneous relatively high signal intensity with scattered low and high signal intensity areas on T2-weighted MR images. An excision was performed after needle biopsy with presumptive diagnosis of bicipitoradial bursitis. The histological specimen revealed an epithelioid cell granuloma with central necrosis. While the occurrence of tuberculous bicipitoradial bursitis has never been reported, this case demonstrates that it can be considered to be among the causes of a cystic lesion around the elbow joint.

Aged↗
PubMed2006

Effect of rotator interval closure on glenohumeral stability and motion: a cadaveric study.

The effect of rotator interval closure, which is performed as an adjunct to arthroscopic stabilization of the shoulder, has not been clarified. Fourteen fresh-frozen cadaveric shoulders were used. The position of the humeral head was measured using an electromagnetic tracking device with the capsule intact, sectioned, and imbricated between the superior glenohumeral ligament and the subscapularis tendon (SGHL/SSC closure) or between the superior and middle glenohumeral ligaments (SGHL/MGHL closure). The direction of translational loads (10, 20, and 30 N) and arm positions were (1) anterior, posterior, and inferior loads in adduction; (2) anterior load in abduction/external rotation in the scapular plane; and (3) anterior load in abduction/external rotation in the coronal plane. The range of motion was measured using a goniometer under a constant force. Both methods reduced anterior translation in adduction. Only SGHL/MGHL closure reduced anterior translation in abduction/external rotation in the scapular plane and posterior translation in adduction. Both methods reduced the range of external rotation and horizontal abduction. Rotator interval closure is expected to reduce remnant anterior/posterior instability and thereby improve the clinical outcomes of arthroscopic stabilization procedures.

Adult↗
PubMed2006

[Paget disease of bone].

Explore the source record for details and available documents.

Adaptor Proteins, Signal Transducing↗
PubMed2006

The effect of the inferior capsular shift on shoulder intra-articular pressure: a cadaveric study.

BACKGROUND: The inferior capsular shift procedure is commonly performed for multidirectional instability of the shoulder with excellent clinical results. HYPOTHESIS: The mechanism of this procedure is to increase shoulder stability by changing the responsiveness of intra-articular pressure to downward loading. STUDY DESIGN: Controlled laboratory study. METHODS: In 7 fresh-frozen cadaveric shoulders, inferior capsular shift was simulated by imbricating the anterior and posterior capsule using clamps. The position was monitored using an electromagnetic tracking device with the glenohumeral joint capsule intact, imbricated anteriorly, or imbricated anteriorly and posteriorly and with the inferior load of 0, 0.5, or 1.0 kg. Simultaneously, intra-articular pressure was monitored using a pressure transducer. Saline was injected into the glenohumeral joint to measure capsular volume. The capsule was vented, and the position was again measured. RESULTS: Intra-articular pressure was -71 +/- 19, -221 +/- 70, and -366 +/- 73 cm H(2)O with 0, 0.5, and 1.0 kg of load, respectively, with the capsule intact. With anterior imbrication, intra-articular pressure decreased to -79 +/- 10, -274 +/- 103, and -460 +/- 135 cm H(2)O, respectively, and with anterior and posterior imbrication, intra-articular pressure further decreased to -87 +/- 16, -308 +/- 74, and -548 +/- 39 cm H(2)O, respectively. The volume of the intact shoulder (36 +/- 9 mL) significantly decreased to 27 +/- 7 mL (75%) with anterior imbrication and to 15 +/- 5 mL (42%) with anterior and posterior imbrications (P = .0001). Before venting the capsule, inferior displacement was 5% of the vertical length of the glenoid, even with 1.0 kg of load with any capsular conditions. After venting, the humeral head dislocated inferiorly in all shoulders, even after imbrications. CONCLUSION: The inferior capsular shift procedure decreases joint volume and increases responsiveness of intra-articular pressure to downward loading. CLINICAL RELEVANCE: Biomechanical data provide scientific background to the commonly performed procedures of inferior capsular shift and thermal capsular shrinkage.

Adult↗
PubMed2006

Vascularized iliac bone graft for iliosacral bone defect after tumor excision.

We present the clinical outcome of five patients who had reconstruction of large osseous defects in the iliosacral region after excision of aggressive bone tumors using pedicled-or free-vascularized iliac bone grafts. Surgical margin, incidence of recurrence and metastasis, patient survival, time to bone union, and postoperative function were evaluated. Limb-salvage surgery resulted in wide excisions in two patients with giant-cell tumors of bone and chordoma, respectively, a marginal excision in one patient with a schwannoma, and intralesional excisions to preserve nerve roots in two patients with giant-cell tumors. There was no recurrence at final followup in any of the patients. Bone union required an average of 5.4 months. The postoperative functional results were excellent in all patients except for the patient with a chordoma. In one of the patients with a giant-cell tumor, the screws and rod were removed partially because of skin necrosis in the instrumentation area. This technique is considered a good alternative for reconstruction of a large osseous defect in the pelvis because graft harvest is relatively simple and rapid, especially if a pedicled iliac bone transfer is performed.

Adult↗
PubMed2006

Decompression of idiopathic lumbar epidural lipomatosis: diagnostic magnetic resonance imaging evaluation and review of the literature.

OBJECT: Idiopathic symptomatic spinal epidural lipomatosis (SEL) is a rare condition, and few reports have discussed diagnostic imaging criteria. To evaluate factors relating to its clinical symptoms, correlations between clinical features and the presence of spinal epidural fat were investigated, and the literature concerning idiopathic SEL was reviewed. METHODS: Morphological gradings of epidural fat were evaluated in seven patients with idiopathic SEL by using magnetic resonance (MR) imaging. In addition, body mass index (BMI), the number of involved vertebral levels, grade, and preoperative Japanese Orthopaedic Association (JOA) score were analyzed. Surgery resulted in symptomatic relief, with a mean JOA score recovery rate of 67.4%. Grading of epidural fat tended to display a slight negative correlation with preoperative JOA score, whereas a strong significant positive correlation was found between the number of involved vertebral levels and BMI. CONCLUSIONS: The number of involved vertebral levels and obesity are strongly correlated, whereas severity of dural compression is not always significantly associated with neurological complications. These results indicate that epidural fat of the lumbar spine contributes to neurological deficits. In addition, weight-reduction therapy appears to decrease the number of vertebral levels involved. Magnetic resonance imaging-based grading is helpful for the diagnosis and evaluation of idiopathic lumbar SEL. Moreover, symptoms and neurological findings are important for determining the surgical approach.

Adipose Tissue↗
PubMed2006

Objective evaluation of shoulder pain by measuring skin impedance.

The subjective nature of pain has made its objective evaluation rather difficult. Recently, skin impedance was reported to reflect pain. The purpose of this study was to determine the usefulness of measuring skin impedance in evaluating shoulder pain. Fifty-three patients with shoulder pain were examined. Skin impedance was measured by a skin impedance meter in three different conditions and was compared with the visual analog scale recorded at the same time.

Adult↗
PubMed2005

Effects of intraarticular administration of basic fibroblast growth factor with hyaluronic acid on osteochondral defects of the knee in rabbits.

INTRODUCTION: Growth factors including basic fibroblast growth factor (bFGF) are expected to be useful tools for enhancing osteochondral repair. However, suitable carriers are required to deliver a growth factor to the injury site. We evaluated the effects of intraarticular injection of bFGF with hyaluronic acid (HA) on osteochondral repair and the potential carrier role of HA in this treatment. MATERIALS AND METHODS: Osteochondral defect was created in the medial femoral condyle of rabbits and received single or weekly intraarticular injection of bFGF (1 or 10 microg) with or without HA. Prior to the administration, bFGF was incubated with HA or vehicle-saline for 24 h at 4 degrees C. Four weeks after the initial injection, the animals were killed and the defect was evaluated grossly (12-point scale) and histologically (16-point scale). The effect of single injection of bFGF (1 microg) with HA was also compared to that of the carrier known as gelatin microspheres (GM) incorporating bFGF. RESULTS: Weekly-administered bFGF alone induced undesirable side effects such as inflammatory responses and osteophyte formation. However, weekly-administered 1 mug of bFGF with HA yielded significantly better osteochondral repair than each treatment alone in gross and histological examinations with minimal side effects (P < 0.05). Single administration of 1 microg bFGF with HA but not GM incorporating bFGF showed significantly better osteochondral repair comparing to the vehicle control (P < 0.05). CONCLUSION: Low-dose bFGF with HA was effective for osteochondral repair in rabbits. The significant osteochondral reparative role of bFGF with HA comparing with GM incorporating bFGF might be explained by the potential carrier role of HA and possible synergistic action between these two agents. The combination of HA with bFGF significantly suppressed the side effects resulting from single use of bFGF.

Adjuvants, Immunologic↗
PubMed2005

Contact area, contact pressure, and pressure patterns of the tendon-bone interface after rotator cuff repair.

BACKGROUND: The contact pressure and contact area at the tendon-bone interface after the most commonly used rotator cuff repair methods have not been investigated. HYPOTHESIS: There are no significant differences among the transosseous, the single-row suture anchor, and the double-row suture anchor techniques in terms of contact pressure, contact area, and pressure patterns at the tendon-bone interface. STUDY DESIGN: Controlled laboratory study. METHODS: After creating a full-thickness supraspinatus tendon tear in 10 cadaveric shoulder specimens, we inserted pressure-sensitive film between the tendon stump and the bone, and we repaired the tear by (1) transosseous, (2) single-row suture anchor, and (3) double-row suture anchor techniques. RESULTS: The contact area of the double-row technique was 42% greater than that of the transosseous technique (P < .0001) and 60% greater than that of the single-row technique. The contact area of the transosseous technique was 31% greater than that of the single-row technique (P = .0015). The average pressures of the single-row and double-row techniques were 18% (P = .014) and 16% (P = .03) greater, respectively, than that of the transosseous technique, but there was no significant difference between the single-row and double-row techniques (P = .915). CONCLUSIONS: The double-row technique produced the greatest contact area and the second-highest contact pressure, whereas the single-row technique created the highest contact pressure and the least contact area. The transosseous technique produced the second-greatest contact area and the least contact pressure. CLINICAL RELEVANCE: The double-row suture anchor technique and the transosseous technique may provide a better environment for tendon healing.

Absorbable Implants↗
PubMed2005

Factors related to spinal mobility in patients with postmenopausal osteoporosis.

Quality of life in patients with spinal osteoporosis is impaired by the decline of spinal mobility. However, the factors related to the spinal mobility in these patients are still unclear. We evaluated the possible factors affecting spinal mobility in patients with postmenopausal osteoporosis. A total of 128 postmenopausal women with osteoporosis aged over 50 years (mean, 70 years) were included in this study. The thoracic and lumbar kyphosis angles and range of motion (ROM) of the total spine were measured in the upright position and at maximum flexion/extension with a computer-assisted device. The paravertebral muscle thicknesses (PVMT) of thoracic and lumbar spine in the upright position were measured using an ultrasound unit. The number of vertebral fractures was evaluated with radiographs of the spine. Isometric back extensor strength (BES) was evaluated with a strain-gauge dynamometer. Correlations between these variables were then analyzed. Age (r=-0.412), lumbar kyphosis angle (r=-0.284), BES (r=0.369), PVMT at the lumbar spine (r=0.227) and the number of vertebral fractures (r=-0.260) showed significant correlations with total spinal ROM (P<0.05). However, no significant correlations were observed between the total spinal ROM and PVMT at the thoracic spine (r=-0.069) or thoracic kyphosis angle (r=-0.138). Multiple regression analysis revealed that the BES was the most significant contributor to the total spinal ROM. The present study suggests a possible association between BES and spinal mobility in patients with postmenopausal osteoporosis.

Aged↗
PubMed2005

Effects of reducing resistance, repetitions, and frequency of back-strengthening exercise in healthy young women: a pilot study.

OBJECTIVE: To determine the effects of reducing intensity or frequency of back-strengthening exercise on back extensor strength. DESIGN: Randomized controlled trial. SETTING: Exercises were performed in participants' homes. Instruction and measurements were performed at the rehabilitation center in the hospital. PARTICIPANTS: Fifty-eight healthy female volunteers (mean age, 20 y). INTERVENTIONS: Participants were assigned to 1 of 5 exercise intervention groups: control; standard protocol (STD) that has been shown to increase back extensor strength; weight reduction (WRD); repetition reduction (RRD); and frequency reduction (FRD). Back exercises involved lifting a weighted backpack while in a prone position. The study period was 12 weeks. MAIN OUTCOME MEASURE: Isometric back extensor strength. RESULTS: Back extensor strength increased significantly in all groups except the control group. The maximum increase was achieved by the STD group (39%), followed by the FRD (25%), WRD (22%), RRD (20%), and control (5%) groups. Percentage change in back extensor strength was significantly greater in the STD group than in all other groups except the FRD group. CONCLUSIONS: Back extensor strength in the WRD, RRD, and FRD groups was significantly higher at 12 weeks compared with baseline. Reductions in intensity and frequency resulted in similar effects on increases in back extensor strength.

Adolescent↗
PubMed2005

Attachment types of the long head of the biceps tendon to the glenoid labrum and their relationships with the glenohumeral ligaments.

PURPOSE: To clarify the attachment types of the long head of the biceps tendon to the glenoid labrum and their relationships with the glenoid attachment of the glenohumeral ligaments. TYPES OF STUDY: Anatomic study in cadavers. METHODS: Using 101 cadaver shoulders, the glenoid attachment types of the biceps tendon and the location of the glenoid origin of the glenohumeral ligaments were assessed macroscopically and then histologically on the sagittal section. RESULTS: The glenoid attachment types of the biceps tendon were defined as entirely-posterior in 28 shoulders (27.7%), posterior-dominant in 56 shoulders (55.4%), equal in 17 shoulders (16.8%), and entirely anterior in none (0%). In all shoulders, the superior and middle glenohumeral ligaments were attached between 12 and 1 o'clock (average, 12:36 o'clock), whereas the inferior glenohumeral ligament (IGHL) showed greater variation. In the posterior-dominant and equal types, the IGHL was attached relatively high (average 2:49 o'clock for the posterior-dominant type and 1:49 o'clock for the equal type). In the entirely posterior type, the IGHL was attached low, between 4 and 5 o'clock (average, 4:32 o'clock). There was a significant difference between them (P < .001). Histologic examination showed that in the posterior-dominant and equal types, the fibers of the IGHL directly linked to the fibers of the biceps tendon, whereas in the entirely posterior type no such direct connections were observed. However, in all types, the fibers of the biceps tendon were attached to the posterior labrum. CONCLUSIONS: The labral attachment of the long head of biceps tendon was posterior regardless of its macroscopic appearance. The macroscopic attachment pattern of the biceps tendon resulted from the different attachment height of the IGHL. The attachment site of the IGHL is lower than 4 o'clock in the entirely posterior type, whereas it is higher than 4 o'clock in other types. CLINICAL RELEVANCE: The present study provides useful information about the original attachment site of the IGHL during Bankart repair.

Anthropometry↗
PubMed2005

Cross-sectional area of the tendon and the muscle of the biceps brachii in shoulders with rotator cuff tears: a study of 14 cadaveric shoulders.

BACKGROUND: The intraarticular portion of the long head of the biceps tendon is often widened in shoulders with cuff tears. It is unclear whether this is a local phenomen or is caused by muscle hypertrophy. METHODS: We investigated morphological changes of the biceps brachii in 14 embalmed shoulders: 7 with intact rotator cuff and 7 with rotator cuff tears. We measured the cross-sectional area (CSA) of the tendon of the long head of the biceps (LHB) at 9 levels between the glenoid origin and the musculotendinous junction. The muscle volume and the muscle fiber length of the long and short heads of the biceps were measured to calculate the physiological CSA (PCSA) by dividing the volume by the fiber length. RESULTS: The CSA of the LHB tendon at the entrance to the bicipital groove was greater in cuff tear shoulders than in normal shoulders. The PCSA of the biceps was similar in normal and cuff tear shoulders. INTERPRETATION: Hypertrophy of the LHB tendon appears to be a localized morphological change near the entrance to the bicipital groove.

Aged↗
PubMed2005

Evaluating benign and malignant musculoskeletal lesions with radionuclide angiography and SPECT using Tc-99m MIBI.

PURPOSE: The purpose of this study was to evaluate the use of radionuclide angiography and single photon emission computed tomography (SPECT) using Tc-99m hexakis-2-methoxyisobutylisonitrile (Tc-99m MIBI) for analyzing musculoskeletal lesions. MATERIALS AND METHODS: Radionuclide angiography and SPECT using Tc-99m MIBI were performed in 36 patients with various soft tissue and bone pathologies (18 benign and 18 malignant lesions). The ratio of the counts of the lesion to that of the contralateral normal area was calculated from the region of interest drawn on the MIBI scan. The MIBI-uptake ratio was calculated using SPECT and the MIBI-perfusion index was calculated using radionuclide angiography. RESULTS: The MIBI-uptake ratio in malignant lesions (4.80 +/- 4.43) was significantly higher (P < 0.05) than that in benign lesions (1.83+/-2.48). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the MIBI-uptake ratio for malignant lesions were 72%, 83%, 78%, 81%, and 75%, respectively. The MIBI-perfusion index in malignant lesions (17.68 +/- 21.19) was significantly higher (P < 0.05) than that in benign lesions (2.25 +/- 2.56). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the MIBI-perfusion index for malignant lesions were 87%, 75%, 81%, 77%, and 86%, respectively. CONCLUSIONS: The MIBI-uptake ratio and MIBI-perfusion index using Tc-99m MIBI can yield important additional information with which to differentiate musculoskeletal lesions.

Adolescent↗
PubMed2005

Ligamentum flavum hematoma in the rigid thoracic spinal segments: case report.

Ligamentum flavum hematoma, a rare cause of spinal nerve root and canal compression, typically occurs in the mobile lumbar spine segments. A thoracic ligamentum flavum hematoma is extremely rare--only one such case of a thoracolumbar (T11-12) lesion has been reported. The thoracolumbar region with its floating ribs, however, is structurally and biomechanically similar to the lumbar spine and its mobility is greater than the higher thoracic levels. To the best of their knowledge, the authors report the first case of a ligamentum flavum hematoma in the region of the rigid thoracic spinal segments with the contiguous rib cage. A symptomatic T9-10 ligamentum flavum hematoma is described in the case of a 66-year-old woman with compensatory thoracic lordosis secondary to the lumbar degenerative kyphosis. The hematoma was removed and the diagnosis was histologically confirmed. The authors speculate that thoracic lordosis might have contributed to the development of the hematoma because the ligamentum flavum and the facet joint were subjected to greater axial stress than in individuals with normal spinal alignment.

Aged↗