[Findings of the subcoracoid bursa on MR arthrography and their clinical significance].

We studied visualization of the subcoracoid bursa by conducting a retrospective analysis of the MR arthrograms of 101 shoulders with surgical confirmation. MR arthrography showed the subcoracoid bursa in 28 shoulders, among which the bursa was revealed by inadvertent direct injection of contrast material into the bursa in 10 shoulders. Of the remaining 18 shoulders, 16 shoulders had rotator cuff tears, one had shoulder instability, and one had dislocation of the long head of the biceps tendon.

Unusual variant of liposarcoma with multiple punctate calcifications.

We report a case of liposarcoma in a 17-year-old boy in which both the radiographs and histology demonstrated multiple punctate calcifications. In addition, this unusual variant consisting of myxoid, round cell and well-differentiated liposarcoma behaved aggressively resulting in the death of the patient.

Decreased interposition after closed reduction in the hip joint: a case of developmental dislocation of the hip observed by MRI.

A 4-month-old Japanese girl with a developmental dislocation of the right hip was treated with manual reduction under general anesthesia followed by cast immobilization. Serial magnetic resonance imaging (MRI) revealed that a large interposition of fat tissue in the acetabulum, observed immediately after cast immobilization, became remarkably small in size as the congruity improved after 3 weeks. These MRI findings demonstrate the mechanism of a "squeezing phenomenon" after reduction of the hip.

Stronger back muscles reduce the incidence of vertebral fractures: a prospective 10 year follow-up of postmenopausal women.

The long-term protective effect of stronger back muscles on the spine was determined in 50 healthy white postmenopausal women, aged 58-75 years, 8 years after they had completed a 2 year randomized, controlled trial. Twenty-seven subjects had performed progressive, resistive back-strengthening exercises for 2 years and 23 had served as controls. Bone mineral density, spine radiographs, back extensor strength, biochemical marker values, and level of physical activity were obtained for all subjects at baseline, 2 years, and 10 years.

Atrophy of the rotator cuff muscles and site of cuff tears.

We determined the relationship between the site of rotator cuff tears and atrophy of the cuff muscles. 28 shoulders (28 patients) had rotator cuff tears: 19 isolated tears of the supraspinatus tendon (isolated-tear group) and 9 combined tears of the supraspinatus and infraspinatus tendons (combined-tear group). The cross-sectional area of the subscapularis, supraspinatus, the infraspinatus and teres minor muscles in the coronal oblique MR images were measured before and after surgery.

Posterior pelvic tilt in patients with decreased lumbar lordosis decreases acetabular femoral head covering.

The relationship between pelvic tilt and acetabular femoral head covering was determined in 38 patients with decreased lumbar lordosis. Posterior pelvic tilt and acetabular femoral head covering were measured on radiographs taken in both supine and standing positions. Previously reported normal values obtained from 96 patients were used as controls.

Enhanced antitumor effect of ultrasound in the presence of piroxicam in a mouse air pouch model.

The antitumor effects of piroxicam, a non-steroidal anti-inflammatory drug, on sarcoma 180 cells under ultrasonic irradiation were examined in a mouse air pouch model. When piroxicam was added to sarcoma 180 suspension under ultrasound irradiation (2 MHz, 10 W, 120 s), the mortality rate of tumor cells immediately after the irradiation and the survival rate of mice were significantly higher than those when ultrasound alone was applied, and these effects of piroxicam were dose-dependent. When D-mannitol was used with piroxicam, the mortality rate of the tumors cells after the irradiation was comparable with that when piroxicam alone was applied, but when L-histidine was used concurrently, the antitumor effect was significantly lower than that when piroxicam alone was applied.

Glenoid osteophyte and rotator cuff tears: an anatomic study.

The purpose of this study was to determine the morphologic characteristics of the glenoid osteophyte and its relationship to rotator cuff tears. Eighty-six cadaveric shoulders were studied. After inspection of cuff pathology, the glenoid was examined with soft x-rays.

Early MRI findings of rapidly destructive coxarthrosis.

Rapidly destructive coxarthrosis (RDC) is known to affect elderly women, but its etiology is unknown. This is the first report to our knowledge, based on a search of the English literature, that reveals the entire process of hip destruction from the onset to the terminal stage of RDC, in an 80-year-old woman. Radiographic evaluation showed subchondral insufficiency fracture of the femoral head at an early stage of this disease.

Autologous bone grafting without screw fixation for tibial defects in total knee arthroplasty.

We evaluated 30 knees with autologous bone grafts, performed without screw fixation, for tibial defects in total knee arthroplasty (TKA). The tibial defects were classified into three types: contained, flat peripheral, and slant peripheral. The resected femoral condyle was fixed with a combination of bone cement and the tibial component, without using screws.

Function of the 3 portions of the inferior glenohumeral ligament: a cadaveric study.

The stabilizing function of the inferior glenohumeral ligament of the anterior band and posterior band has been investigated, but little is known about the function of the axillary pouch. The strain of the 3 portions of the inferior glenohumeral ligament in 17 fresh-frozen cadaveric shoulders was measured with use of linear transducers. The measurements were performed under the following conditions: 0 degrees, 30 degrees, 45 degrees, and 60 degrees of glenohumeral elevation in the coronal, scapular, and sagittal planes and internal to external rotations in 10 degrees increments.

Effect of arm elevation and rotation on the strain in the repaired rotator cuff tendon. A cadaveric study.

In 14 cadaveric shoulders, a rotator cuff tear (2 cm wide and 1.5 cm long) was created and repaired under a 3-kg tensile force with the arm in adduction. Strain on the repaired tendon was measured at 0 degrees, 15 degrees, 30 degrees, and 45 degrees of elevation in the sagittal, scapular, and coronal planes and from 60 degrees of internal rotation to 60 degrees of external rotation.

Effect of superior capsule and coracohumeral ligament release on strain in the repaired rotator cuff tendon. A cadaveric study.

Twelve cadaveric shoulders were used to determine the effects of release of the superior capsule and the coracohumeral ligament on the strain in the repaired rotator cuff tendon. A rotator cuff tear (2 cm wide and 1.5 cm long) was created and repaired under a 3-kg tensile force.

Superior labral strain during the throwing motion. A cadaveric study.

We studied the strain on the superior labrum of 10 fresh-frozen cadaveric shoulders with the arm in simulated positions of a pitching motion. We used linear transducers to measure the strain in both the anterior and posterior superior labrum with the arm in various planes and rotations simulating the motions of pitching: early cocking, late cocking, acceleration, deceleration, and follow-through. Predetermined loads, according to the percent of maximum voluntary contraction of the biceps muscle during each phase of pitching, were calculated and applied to the long head of the biceps tendon using a spring device.

Range of motion after Bankart repair. Vertical compared with horizontal capsulotomy.

We studied the range of shoulder motion of patients who underwent vertical as compared with horizontal capsulotomies during open Bankart repair for recurrent anterior dislocations of the shoulder. A vertical capsulotomy was used in 10 shoulders and a horizontal capsulotomy was used in 14 shoulders. Except for the method of capsulotomy, the surgical procedure and postoperative rehabilitation were the same.

Contribution of capsuloligamentous structures to passive static inferior glenohumeral stability.

OBJECTIVE: This study attempted to determine the relative stabilizing effect of the capsuloligamentous structures to inferior humeral displacement. DESIGN: This was an in vitro study, utilizing cadaveric shoulder specimens. BACKGROUND: Inferior glenohumeral instability has come under increasingly close scrutiny in the literature in recent years, yet a description of the precise pathoanatomy is still lacking.

Position of immobilization after dislocation of the glenohumeral joint. A study with use of magnetic resonance imaging.

Background: Glenohumeral dislocations often recur, probably because a Bankart lesion does not heal sufficiently during the period of immobilization. Using magnetic resonance imaging, we assessed the position of the Bankart lesion, with the arm in internal and external rotation, in shoulders that had had a dislocation.

Methods: Coaptation of a Bankart lesion was examined with use of magnetic resonance imaging, with the arm held at the side of the trunk and positioned first in internal rotation (mean, 29 degrees) and then in external rotation (mean, 35 degrees), in nineteen shoulders.

Contact geometry at the undersurface of the acromion with and without a rotator cuff tear.

Purpose: The purpose of this study was to investigate the difference in contact geometry at the undersurface of acromion in shoulders with and without a rotator cuff (RC) tear.

Type Of Study: Case-control study.

Methods: Forty fresh cadaveric shoulders (average age at death, 61 years) without gross osteoarthritic changes were divided into the intact RC group (n = 20) and the RC tear group (n = 20).

Long-term effects of withdrawal of bisphosphonate incadronate disodium (YM175) on bone mineral density, mass, structure, and turnover in the lumbar vertebrae of ovariectomized rats.

This study was designed to evaluate the long-term effects of incadronate disodium (YM175) after its withdrawal on cancellous bone mass in ovariectomized (OVX) rats. Thirteen-week-old female SD rats were randomized into four groups: sham-operated, OVX, low-YM, and high-YM (0.01 mg/kg or 0.

Intra-articular membranous interposition detected by MRI in developmental dysplasia of the hip.

Intra-articular membranous interposition was detected by MRI in the hip joint with residual subluxation of a girl aged 5 years 10 months. This structure, which had low signal intensity on both T1- and T2-weighted images, separated the femoral head from the acetabulum. Histological examination revealed chondrometaplasia, which suggested that this interposition might be transformed to a surface cartilaginous tissue of the secondary acetabulum often observed in residual subluxation of the hip.

A rare anatomic variant of the superior glenohumeral ligament.

The attachment of the superior glenohumeral ligament (SGHL) to the upper pole of the glenoid is variable and 3 types have been described. We report an anatomic variant of SGHL attachment to the upper pole of the glenoid that has not heretofore been reported in the literature. In this case, the SGHL overrode the biceps origin, continued to the superior labrum posteriorly, and had no attachment to the middle glenohumeral ligament or the anterior labrum.

Prediction of muscle force involved in shoulder internal rotation.

The estimation of shoulder muscle force is important to understand the mechanism of rotator cuff injury. In general, mean parameter values are used as input for computational models. However, anatomic and biomechanical parameters vary widely among people.