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Eiji Itoi

Publications and source records attributed to Eiji Itoi.

At least 19 recordsLinked to original sources
PubMed2007

Stress distribution in the supraspinatus tendon after tendon repair: suture anchors versus transosseous suture fixation.

BACKGROUND: The stress concentration at the site of supraspinatus tendon repair, either by suture anchor fixation or by transosseous suture fixation, has not been fully clarified. HYPOTHESIS: Suture anchor fixation showed higher stress concentrations in the tendon than did transosseous suture fixation. STUDY DESIGN: Controlled laboratory study. METHODS: Three finite element models were developed based on a previously published model of normal supraspinatus tendon (0 degrees abduction). Single-row fixation, double-row fixation, and transosseous suture fixation were simulated. A tensile force was applied to the proximal end of the supraspinatus tendon to simulate its contraction force. RESULTS: In the single-row model, the stress appeared from the site of the anchor and extended into the proximal tendon. The highest stress concentration was observed on the bursal surface of the tendon. The double-row model showed a similar pattern to the single-row model except that the stress concentration was observed only around the medial anchor. In the transosseous model, the stress appeared from the attachment site to a bony trough, which extended proximally into the tendon substance. No significant stress concentration was observed inside the tendon. CONCLUSION: Both single-row and double-row fixations showed higher stress concentration inside the tendon than did transosseous suture fixation. CLINICAL RELEVANCE: A high stress concentration might be a cause of the rerupture often observed after arthroscopic cuff repair using suture anchors.

Adaptation, Physiological↗
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

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

Comparison of the MR findings on indirect MR arthrography in patients with rotator cuff tears with and without symptoms.

PURPOSE: To compare indirect magnetic resonance (MR) arthrography findings in patients with rotator cuff tears with and without symptoms. MATERIALS AND METHODS: Indirect MR arthrography results of 15 asymptomatic and 23 symptomatic rotator cuff tears were retrospectively reviewed, comparing the type and size of tears and amount of subacrominal-subdeltoid bursal fluid. RESULTS: There were 14 partial-thickness tears and one full-thickness tear in the asymptomatic group, with 4 small and 11 medium tears. In the symptomatic group, there were 16 partial-thickness and 7 full-thickness tears, with 14 small, 5 medium, and 4 large tears. In the asymptomatic group, the amount of subacrominal-subdeltoid bursal fluid was grade 0, 6 patients; grade 1, 6 patients; grade 2, 2 patients; and grade 3, 1 patient. In the symptomatic group, the amount of subacrominal-subdeltoid bursal fluid was grade 0, 4 patients; grade 1, 3 patients; grade 2, 8 patients; and grade 3, 8 patients. We found no statistically significant difference between symptomatic and asymptomatic tears in the kind and size of tears, and in the amount of subacrominal-subdeltoid bursal fluid. CONCLUSION: We found no difference in the MR findings between symptomatic and asymptomatic rotator cuff tears.

Aged↗
PubMed2006

Effects of alfacalcidol alone or in combination with elcatonin on incidence of osteoporotic vertebral fractures in postmenopausal women with spondylosis.

Osteoporosis and spondylosis often occur simultaneously. However, there are no previous reports about the effects of osteoporosis medication on incidence of vertebral fractures in people with spondylosis. In this study, we conducted a retrospective investigation of the effects of alfacalcidol alone or in combination with elcatonin on incidence of osteoporotic vertebral fractures in women with spondylosis. The present subjects were 101 postmenopausal women with osteoporosis aged >60 years, divided into three groups: D group (n = 45), treated for >5 years with alfacalcidol; D+ECT group (n = 26), treated for >5 years with alfacalcidol plus elcatonin; control group (n = 30), who received no medications for >5 years. Over the 5-year treatment period, bone mineral density (BMD) of the lumbar spine and proximal femur did not significantly change in the D and D+ECT groups, but they significantly decreased in the control group (P < 0.05). The number of incident vertebral fractures per patient was significantly higher in the control group (2.9) than in the D group (1.2) and D+ECT group (1.5) (P < 0.01). There was no significant difference in BMD or incident vertebral fractures between the D and D+ECT groups. In all three groups, the number of incident vertebral fractures positively correlated with the number of prevalent vertebral fractures (0.303 </= r </= 0.434), and negatively correlated with baseline BMD (-0.703 </= r </= -0.326) and the osteophyte score representing the degree of spondylosis (-0.769 </= r </= -0.365). Further multiple regression analysis revealed that the medication (D or D+ECT, P < 0.001) and the osteophyte score (P < 0.001) were the most significant contributors for the number of incident vertebral fractures. In conclusion, elcatonin had no additive effects on BMD or prevention of vertebral fractures in postmenopausal women receiving alfacalcidol. Presence of spondylosis (indicated by a high osteophyte score) appears to have an effect on prevention of vertebral fractures.

Aged↗
PubMed2006

Dural substitute with polyglycolic acid mesh and fibrin glue for dural repair: technical note and preliminary results.

BACKGROUND: An ideal dural substitute that enables watertight closure, has sufficient strength, and can be absorbed without remnant materials that induce inflammation, adhesion, and infection is not available. The purpose of this study was to evaluate the efficacy of a bioabsorbable polyglycolic acid (PGA) mesh and fibrin glue as a substitute for dural repair. METHODS: Altogether, 10 patients with noted dural tears during extradural spinal surgery and 20 patients who underwent durotomy for intradural spinal surgery were included in this study. In a series of 20 consecutive cases, dural closure was performed by suture and fibrin glue. In the subsequent 10 consecutive patients, dural closure was performed by suture and fibrin glue with the use of absorbable PGA mesh. The medical records and magnetic resonance imaging (MRI) of the surgical site were retrospectively reviewed to evaluate the presence of a cerebrospinal fluid (CSF) fistula or leakage after the surgery. RESULTS: A CSF fistula occurred in five patients who underwent dural repair with fibrin glue alone, and postoperative MRI showed CSF leakage in two patients with incidental dural tears after laminectomy for ossification of ligamentum flavum. No CSF fistula was present in patients who underwent dural repair using PGA mesh and fibrin glue, and no adverse effects or complications were encountered postoperatively. Follow-up MRI revealed no evidence of CSF leakage around the reconstructed dura mater. CONCLUSIONS: The use of PGA mesh and fibrin glue for the repair of dura mater is a useful method of preventing CSF leakage in spinal surgery.

Adolescent↗
PubMed2006

Effects of unipedal standing balance exercise on the prevention of falls and hip fracture among clinically defined high-risk elderly individuals: a randomized controlled trial.

BACKGROUND: The aim of this study was to assess the effectiveness of the unipedal standing balance exercise for 1 min to prevent falls and hip fractures in high-risk elderly individuals with a randomized controlled trial. This control study was designed as a 6-month intervention trial. SUBJECTS: Subjects included 553 clinically defined high-risk adults who were living in residences or in the community. They were randomized to an exercise group and a control group. METHODS: Randomization to the subjects was performed by a table of random numbers. A unipedal standing balance exercise with open eyes was performed by standing on each leg for 1 min three times per day. As a rule, subjects of the exercise group stood on one leg without holding onto any support, but unstable subjects were permitted to hold onto a bar during the exercise time. Falls and hip fractures were reported by nurses, physical therapists, or facility staff with a survey sheet every month. This survey sheet was required every month for both groups. RESULTS: Registered subjects were 553 persons ranging in age from 37 to 102 years (average, 81.6 years of age). Twenty-six subjects dropped out. The number of falls and hip fractures for the 6-month period after the trial for 527 of the 553 subjects for whom related data were available were assessed. The exercise group comprised 315 subjects and the control group included 212 subjects. The cumulative number of falls of the exercise group, with 1 multiple faller omitted, was 118, and the control group recorded 121 falls. A significant intergroup difference was observed. However, the cumulative number of hip fractures was only 1 case in both groups. This difference was not statistically significant. CONCLUSIONS: The unipedal standing balance exercise is effective to prevent falls but was not shown to be statistically significant in the prevention of hip fracture in this study.

Accidental Falls↗
PubMed2006

Clinical features of cauda equina tumors requiring surgical treatment.

In this study, we evaluated the clinical features of cauda equina tumors requiring surgical treatment. Medical records of 28 patients with cauda equina tumors (13 men and 15 women) undergoing surgical treatment were retrospectively reviewed. The majority of histological diagnoses indicated schwannoma (23 cases, 82%), and the remaining 5 indicated ependymoma, neurofibroma, meningioma, and ganglioneuroblastoma. In 86% of the cases, the initial symptom was pain in the lower back and/or lower extremities. Preoperatively, half of the patients had symmetrical pain in the lower back or lower extremities, severe pain in the supine position, or pain that was increased by coughing. One third of the patients needed morphine to control nocturnal pain. Tumor size, as determined by magnetic resonance imaging (MRI), correlated with preoperative symptom duration (r = 0.66, p < 0.001). These findings indicate that symmetrical lower back pain and/or pain that radiates to both lower extremities and increases in the supine position are characteristic of cauda equina tumors. The correlation between symptom duration and tumor size indicates that earlier diagnosis of this tumor is necessary. Earlier diagnosis based on these characteristic symptoms should make use of further examinations such as MRI.

Adolescent↗
PubMed2006

Hybrid functional electrical stimulation with medial linkage knee-ankle-foot orthoses in complete paraplegics.

We have previously restored ambulation in paraplegics by performing hybrid functional electrical stimulation (FES) with medial linkage knee-ankle-foot orthosis (MLKAFO). The most common MLKAFO (hinge-type MLKAFO) has the hypothetical axis that is lower than the physiological hip joint position, resulting in slow velocity and short step length. A new MLKAFO (sliding-type MLKAFO), which uses sliding medial linkages, has been developed to correct the axial discrepancy of the hinge-type MLKAFO that causes limited hip joint excursion. There have been reports of instability associated with sliding medial linkages, but the mechanism of this instability is unclear. The purpose of the present study was to evaluate the effects of FES with MLKAFOs on ambulation in paraplegics. Two complete paraplegic patients (levels T8 and T12, respectively) participated in this study. Kinematics data during ambulation were obtained using a motion analysis system. We measured gait velocity and hip progression during the standing phase. The sliding-type MLKAFO produced faster gait velocity than did the hinge-type MLKAFO, but it caused pelvis instability without FES. Pelvis instability was controlled by hybrid FES using the sliding-type MLKAFO. With hybrid FES, the sliding-type MLKAFO provides better gait performance than the hinge-type MLKAFO, but the hinge-type MLKAFO provides greater pelvis stability during walking. Moreover, FES provides sufficient propulsion to allow the complete paraplegics to walk.

Adult↗
PubMed2006

Chronic subdural hematoma coexisting with ligamentum flavum hematoma in the lumbar spine: a case report.

We present a case of a chronic spinal subdural hematoma combined with a ligamentum flavum hematoma in the lumbar spine treated surgically. An 83-year-old woman receiving antiplatelet medicine due to an angina suffered from pain in her lower extremity and gait disturbance after a backward fall. Radiological findings including magnetic resonance imaging (MRI) revealed hematoma in the ligamentum flavum at the level of L2 - L3 and a chronic subdural hematoma at the level from L3 to L5. Laminectomy through L2 to L5 was performed and a hematoma existing in the ligamentum flavum and cystic mass was removed. A chronic subdural hematoma was spontaneously evacuated after splitting of the dura mater and an intact arachnoid membrane was observed with no leakage of cerebrospinal fluid. Her clinical symptoms completely disappeared after surgery. To the best of our knowledge, this is the first case of combination of chronic subdural hematoma and ligamentum flavum hematoma in the lumbar spine treated by surgery. Chronic spinal subdural hematoma and hematoma in the ligamentum flavum should be considered as a cause of progressive nerve root compression in patients with anticoagulant therapy, and an appropriate pre-operative diagnosis would be needed to achieve complete decompression of subdural and epidural hematoma.

Aged, 80 and over↗
PubMed2006

Reduction of muscle fatigue by catchlike-inducing intermittent electrical stimulation in rat skeletal muscle.

Catchlike property is the force enhancement produced when a brief, high-frequency burst of pulses is added to a constant low-frequency stimulation. In functional electrical stimulation, constant low-frequency stimulation of approximately 20 Hz has primarily been used to reduce muscle fatigue. The purpose of this study was to investigate the effects of catchlike-inducing intermittent stimulation on muscle fatigue in relation to continuous intermittent low-frequency stimulation. Twenty-two adult male Wistar ST rats were randomly assigned into the constant frequency stimulation (CFS) group or the catchlike-inducing stimulation (CIS) group. In the CFS group, constant low-frequency stimulation of 20 Hz was applied intermittently (4 seconds "ON"/15 seconds "OFF"). In the CIS group, a single electrical burst of 100 Hz was applied at the start of the every 4-second period of stimulation. The muscle fatigue test lasted for 16 min and isometric muscle force, muscle fatigue, and muscular workload were evaluated. CIS significantly increased the maximum muscular force (under fatigued condition) and workload, and significantly decreased muscle fatigue (p < 0.05). The results of this study suggest that catchlike-inducing intermittent electrical stimulation is useful in the clinical administration of functional electrical stimulation.

Animals↗
PubMed2006

Effects of therapeutic magnetic stimulation on acute muscle atrophy in rats after hindlimb suspension.

In most subjects with spinal cord injury, the spinal neurons below the level of injury are spared. Therefore, it is conceivable that the skeletal muscles innervated by these spinal nerves can be activated by applying therapeutic magnetic stimulation along the dorsal spine. The purpose of this study was to evaluate the ability of magnetic stimulation to prevent acute muscle atrophy in rats after hindlimb suspension. Forty adult male Wistar rats were randomly assigned to stimulated and non-stimulated (control) groups. Their hindlimbs were unweighted using a suspension method, causing muscle atrophy. In the stimulation group, magnetic stimulation (20 Hz, 60 min per day) was applied to the sciatic nerve for 10 days. After the stimulation period, the tibialis anterior (TA) and extensor digitorum longus (EDL) were surgically removed and histologically measured. The lesser diameters of type 1, 2A, and 2B muscle fibers were significantly greater in the stimulated group than in the non-stimulated group for both the TA and EDL (p < 0.05). The mean difference in lesser fiber diameter was 20% (range, 14%-27%). These results suggest that therapeutic magnetic stimulation is an effective method of preventing muscle atrophy.

Acute Disease↗
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

Spondylolisthesis of the thoracic spine. Case report.

The thoracic spine is stabilized in the anteroposterior direction by the rib cage and the facet joints. Spondylolisthesis of the thoracic spine is less common than that of the lumbar spine. The authors describe a rare case of thoracic spondylolisthesis in which the patient suffered back pain and myelopathy. The patient was a 44-year-old woman. Plain radiography revealed Grade I T11-12 spondylolisthesis. The pedicle-facet joint angle at T-11 was 118 degrees, greater than that of T-10 or T-12. Postmyelography computerized tomography scanning revealed posterior compression of the dural sac as well as enlargement of and degenerative changes in the facet joint at T-11. Magnetic resonance imaging showed anterior and posterior compression of the spinal cord at the level of the spondylolisthesis. To achieve posterior T10-12 decompression, the surgeons performed a laminectomy and posterolateral fusion in which a pedicle screw fixation system was placed. The patient's back pain disappeared immediately after the operation. The authors conclude that the enlargement of the pedicle-facet joint angle and the degenerative changes of the facet joint caused the thoracolumbar spondylolisthesis.

Adult↗
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↗