A review of biomechanics of the shoulder and biomechanical concepts of rotator cuff repair

AbstractIn this article, we describe the basic knowledge about shoulder biomechanics, which is thought to be useful for surgeons. Some clinical reports have described that the excellent outcome after cuff repair without acromioplasty and a limited acromioplasty might be enough for subacromial decompression. It was biomechanically demonstrated that a 10-mm medial shift of the tendon repair site has a minimum effect on biomechanics. Many biomechanical studies reported that the transosseous equivalent repair was superior to other techniques, although the tendon may lose its inherent elasticity. We herein introduce our recent experiment data and latest information on biomechanics

Two Cases of Acrodermatitis Continua of Hallopeau Associated with Generalized Arthritis

We report two cases of acrodermatitis continua of Hallopeau with generalized arthritis. Oral cyclosporin together with topical steroid were effective for the skin disorders, but not for the arthritis, whereas infliximab and salazosulfapyridine improved the general arthritis. Although arthritis is usually more refractory to conventional therapies, the arthritis in acrodermatitis continua of Hallopeau is likely to be improved by intravenous infliximab together with methotrexate as well as by oral salazosulfapyridine, similar to psoriatic arthritis

Severe Facet Joint Arthrosis Caused C7/T1 Myelopathy: A Case Report

Cervical myelopathy is caused by degenerative processes of the spine including intervertebral disc herniation and posterior spur usually developing at C3/4 to C5/6. C7/T1 single level myelopathy is very rare because of the anatomical characteristics. Facet joint arthrosis can be a cause of cervical myelopathy but only a few cases have been reported. The authors report an extremely rare case of C7/T1 myelopathy caused by facet joint arthrosis. A 58-year-old male presented with hand and gait clumsiness. The radiological examinations revealed severe C7/T1 facet joint arthrosis with bony spur extending into the spinal canal, which compressed the spinal cord laterally. The T1 spinous process indicated nonunion of a “clay-shoveler's” fracture, which suggested that his cervico-thoracic spine had been frequently moved, and thus severe arthrosis had occurred in the facet joints. A right hemilaminectomy of C7 and C7/T1 facetectomy with single level spinal fusion led to complete neurological improvement

Coverage of the Humeral Head by the Coracoacromial Arch: Relationship with Rotator Cuff Tears

The pathogenetic roles of the coracoacromial arch in the development of rotator cuff tears are still controversial. This study compared the anteroposterior coverage of the humeral head by the coracoacromial arch between shoulders with and without full-thickness rotator cuff tears. Forty-two shoulders from 21 embalmed cadaveric specimens were macroscopically examined. Specimens were divided into 2 groups:shoulders with full-thickness cuff tears (tear group) and those with intact cuff tendons (normal group). The coverage angle of each component of the coracoacromial arch was measured using true lateral photographs. We also measured the angle of the total arc of the coracoacromial arch, as well as the angle of the anterior acromial projection. These data were compared between the tear group and the normal group. Although no significant differences were observed in the total arc of the coracoacromial arch between the groups, the tear group had significantly less coverage by the coracoacromial ligament than did the normal group (p＜0.05). Moreover, greater anterior acromial projection was observed in the tear group (p＜0.05). These results suggest that greater coverage of the bony structures on the rotator cuff may correlate with the development of rotator cuff tears

Bony island within the articular cartilage of the knee in a child: a rare condition for early osteoarthritis

Articular cartilage is a specific type of connective tissue composed of hydrated proteoglycans within a matrix of collagen fibrils. In the elderly population, it shows degenerative changes that may results in osteoarthritis. The more severe form of osteoarthritis occasionally demonstrates bone formation within the cartilage, which is designated as a bony protuberance, however, such lesions are rare in children. This report presents the case of a 10-year-old boy with a bony protuberance within the articular cartilage of the knee. The patient initially complained of knee pain and he subsequently developed flexion contracture. Radiological and arthroscopic examinations revealed a bony protuberance in the articular cartilage and degenerative changes of the cartilage above it. He was successfully treated by the removal of the bony protuberance and osteochondral grafting. The bony protuberance may have caused cartilage degradation since the thickness of the cartilage above it was thinner than that around the lesion. The bony protuberance within the articular cartilage formed in the younger population may be a possible cause of osteoarthritis. This case is a noteworthy with regard to the pathogenesis of osteoarthritis

Multiple Bone Metastasis of Sclerosing Epithelioid Fibrosarcoma 12 Years after Initial Surgery—Increasing Ki-67 Labeling Index

Sclerosing epithelioid fibrosarcoma (SEF) is a rare sarcoma of low-grade malignancy. There has been no report to describe the comparison of histological features of SEF between primary and metastatic lesions in spite of high local recurrence rate. We report the histological changes and increasing Ki-67 labeling index of the primary and metastatic lesions of SEF. The patient was a 31-year-old man. At 18, a tumor in the abdominal wall was excised. At 23, the tumor recurred which was removed again. At 30, he was referred to our hospital because of swelling and pain in the chest. Histological examination of the chest wall tumor showed epithelioid cells arranged like alveolar pattern with dense collagen stroma. These findings were consistent with those of SEF. Abdominal and the rib tumors showed the same immunohistochemistrical expression. It is noteworthy that the tumor cells of the rib lesion showed increased cellularity, and its Ki-67 activity was higher as compared with the abdominal tumor, suggestive of progression of malignancy of SEF

Bilateral spondylolysis of inferior articular processes of the fourth lumbar vertebra: a case report

Lumbar spondylolysis, a well known cause of low back pain, usually affects the pars interarticularis of a lower lumbar vertebra and rarely involves the articular processes. We report a rare case of bilateral spondylolysis of inferior articular processes of L4 vertebra that caused spinal canal stenosis with a significant segmental instability at L4/5 and scoliosis. A 31-year-old male who had suffered from low back pain since he was a teenager presented with numbness of the right lower leg and scoliosis. Plain X-rays revealed bilateral spondylolysis of inferior articular processes of L4, anterolisthesis of the L4 vertebral body, and right lateral wedging of the L4/5 disc with compensatory scoliosis in the cephalad portion of the spine. MR images revealed spinal canal stenosis at the L4/5 disc level. Posterior lumbar interbody fusion of the L4/5 was performed, and his symptoms were relieved