Akihiko Hijioka

Degenerative change and rotator cuff tears

SummaryIn order to determine the effects of friction and rubbing in the development of rotator cuff tear, we studied 160 shoulders of 80 cadavers (age at death 43–93 years, mean 69.3 years). Seventy-two cadavers were fixed with formalin and eight were fresh cadavers. The surface of the cuff and the undersurface of the acromion were observed macroscopically. Eight shoulders of fresh cadavers were examined by scanning electron microscopy. Ninety-eight specimens (61%) showed degenerative changes of the supraspinatus tendon. The number of tendons with degeneration and tear increased from the fifth to sixth decade of life, and the size of the tear increased with age. However, there was no sustained increase in the incidence with aging from the age of 60 to 90 years, and the percentage with degenerative changes of the cuff remained at approximately 60% in each decade. Ninety-six specimens (60%) showed degeneration of the subacromial surface. The percentage with degeneration of the undersurface of the acromion remained at approximately 60% from the sixth to ninth decade. There was a significant correlation between the severity of the changes in the rotator cuff and the subacromial surface. Scanning electron microscopy showed changes suggesting effects of friction and rubbing on the rotator cuff, such as regularly arranged wool-like spherical structures on the surface of the tendon and rounded ruptured ends of the tendon fibers. These results indicate that degenerative change of the rotator cuff is aggravated by a friction and rubbing mechanism with the undersurface of the acromion and leads to development of a complete tear.

Lower osteocalcin and osteopontin contents of the femoral head in hip fracture patients than osteoarthritis patients

SummaryIn patients with femoral neck fracture, clinical factors, bone metabolism markers (in serum, urine, and bone), bone mineral density, radiographic parameters, and bone histomorphometric parameters were investigated to detect determinants of fragility fracture. The osteocalcin/deoxypyridinoline ratio and osteopontin/calcium ratio of cortical bone were selected as significant predictors.IntroductionMeasurement of bone mineral density is widely used to assess bone strength, but this also depends on other bone components and on bone structure. The objective of this study was to investigate risk factors for fracture related to bone quality, the patient’s history, and the patient’s lifestyle.MethodsTwenty-one patients with femoral neck fracture and 18 patients with osteoarthritis were enrolled. Blood and urine samples were collected on admission to hospital, and bone samples were obtained from femoral necks resected during surgery. Multivariate logistic regression analysis was performed using osteoarthritis and femoral neck fracture as combined variables to assess the influence of alcohol or coffee intake, eating natto (fermented soybeans), osteocalcin and calcium concentrations, the osteocalcin/deoxypyridinoline ratio and osteopontin/calcium ratios of cortical bone and cancellous bone, various bone histomorphometric parameters, the bone mineral density of the lumbar spine and the intact contralateral femoral neck, and various radiographic parameters of the spineResultsBy forward stepwise multivariate analysis, the osteocalcin/deoxypyridinoline and osteopontin/calcium ratios of cortical bone were selected as significant factors for fracture (the odds ratios were 0.493 and <0.001, respectively; both P < 0.001).ConclusionsA decrease of osteopontin and osteocalcin in bone is important for promoting vulnerability to hip fracture.

Risk factors for long-term treatment of whiplash injury in Japan: analysis of 400 cases

Abstract We studied the risk factors for long-term treatment of 400 patients with whiplash injury in Japan. Most of the patients were injured in rear-end car collisions, but none had cervical bone lesions or spinal cord or root lesions. We evaluated the following risk factors: sex, age, degree of vehicle damage, and admission or non-admission to the hospital. The group of patients younger than 20 years old healed more quickly than patients 30 years or older. Damage to more than half of the car was associated with a longer treatment. Patients who were admitted to the hospital need treatment longer than the non-admission group. Thus, age over 30 years, a large amount of damage to the vehicle, and admission to the hospital are predictors of long-term treatment for whiplash injury in Japan.

Light and electron microscopy of hydroxyapatite depositions in the ligamentum flavum.

Study Design Ligamenta flava obtained from 24 patients who had undergone surgery for degenerative spinal diseases were investigated regarding the histopathology of hydroxyapatite crystal depositions. Objectives Light and electron microscopy and energy dispersive x-ray microanalysis were done to clarify the cause and process of hydroxyapatite crystal depositions in the ligament. Summary of Background Data No reports have been made regarding the cause of calcification in the ligamenta flava induced by hydroxyapatite crystal depositions. Methods Samples were fixed in 10% formalin and 2.5% glutaraldehyde for light and electron microscopy. Energy dispersive x-ray microanalysis was done to detect calcium and phosphate hydroxyapatite crystal deposition areas. Results Hydroxyapatite crystals, which occasionally formed clusters, existed in the connective tissue of the dural side around abundant profiles of growing capillaries. Hydroxyapatite crystals showed needle shaped figures, and the x-ray microanalysis revealed that the ratio of calcium to phosphate was about 1.66:1. A decrease or loss of collagenous and elastic fibers was prominent in these hydroxyapatite deposition areas. Conclusions Hydroxyapatite crystal depositions occur around the growing capillaries in the dural side of the ligamenta flava.

Enlargement of cervical spinal cord correlates with improvement of motor function in upper extremities after laminoplasty for cervical myelopathy.

Objective The correlation between postoperative spinal cord enlargement at the most compressive disc level and clinical outcome is controversial. The relationship between spinal cord enlargement at neurologically symptomatic disc level and clinical recovery has not been explored. The purpose of this study was to clarify the relationship between postoperative spinal cord enlargement at neurologically symptomatic disc level and neurologic outcome. Methods We studied 55 consecutive patients between 1995 and 2002. All patients underwent preoperative neurologic examination to determine the neurologically symptomatic disc level of the spinal cord and computed tomographic myelography twice before and 4 weeks after laminoplasty. The cross-sectional areas of both spinal cord and dural sac from C3/4 to C7/T1 disc levels were measured on computed tomographic myelography images. The Japanese Orthopedic Association scoring system was used for clinical evaluation before and 1 year after surgery. Results Total score improved significantly from 10.2±2.8 (SD) to 13.0±3.0 after operation. Motor and sensory function scores of upper and lower extremities also improved significantly. The enlargement of spinal cord area at the neurologically symptomatic disc level correlated significantly with improvement in motor function scores of upper extremities (rs=0.421 P=0.0052). However, there were no significant relationships between the enlargement of the spinal cord at the most compressive disc level or that at the dural sac and any categories of Japanese Orthopedic Association scoring system. Conclusion Postsurgical enlargement of the cervical spinal cord at the neurologically symptomatic disc level at 4 weeks postoperatively correlated with recovery of motor function of the upper extremities at 1 year.

Clinical Results of Osteosynthesis for Displaced Femoral Neck Fractures in under 70 Years Old

70歳未満の転位型大腿骨頚部骨折に対する骨接合術の治療成績について検討した．対象は2005年から2010年までの6年間で8例（男性2例，女性6例，平均年齢53歳）であり，骨癒合の有無，LSC：late segmental collapse発症の有無について検討した．検討項目は年齢，BMI：body mass index，術前待機日数，術後整復位，正面・側面GAI：Garden alignment index，implant挿入位置とした．骨癒合は8例中6例75％に得られ，LSCは6例中2例33％に発症した．骨癒合に関して，統計学的有意差を認めた項目は整復位と側面GAIであった．整復位がunderreducedで側面GAIが低値の症例では骨癒合が得られにくかった．LSC発症に関して，統計学的有意差を認めた項目は待機日数であり，その平均待機日数は4.5日であった．

Clinical results of the new cervico-thoracic orthosis 'Neck-Chest brace'

The efficacy of a new cervico-thoracic Neck-Chest brace (N-C brace) prepared for post-operative patients of cervical canal expansive laminoplasty was assessed. The orthosis is light in weight (300 g) and easy to fit. The effect of the orthosis to restrict the neck motion was studied in 10 normal young males by using lateral view radiographs in extension and flexion positions. The average range of the neck motion for the N-C brace was 24.4% of the values obtained without the orthosis. The restriction of the motion was significantly better than that without orthosis. Then, the clinical efficacy of the N-C brace was assessed in 40 patients of cervical spondylotic myelopathy who underwent expansive laminoplasty. Alignment changes of the postoperative cervical spine was found only in 10% of the patients who had a straight and kyphotic curvature pattern in the cervical spine before operation. The cervical alignments in the other 90% of patients were not changed post-operatively. These data clearly demonstrated that the N-C brace effectively controls the neck motion and is recommended for patients who have a lordotic curvature pattern in the cervical spine to prevent the post-surgical changes in the alignment after expansive laminoplasty.

A Case of Subarachnoid Hematoma in Conus Medullaris

Spinal subarachnoid hematoma is a very rare disorder with few cases reported in Japan. This disorder may be due to tumor, disorders of vessels, coagulation dysfunctions, trauma or of unknown etiology. We report a case of subarachnoid hematoma with hypertension, in which the cause of the bleeding was not found.A 68-year-old male presented with sudden onset of pain in the bilateral femoral area, and gluteal area. He had a decrease of leg muscularity, and developed urinary retention on November 9, 1993. On admission, spinal MRI showed a space occupying lesion in his spinal canal at L1-L3 and lumbar puncture showed bloody CSF, and developed protein. He was suspected of having a spinal tumor and was transferred to our hospital on November 29. We suspected subarachnoid hematoma, so laminectomy was performed and the hematoma was removed on the same. Post-operatively, he had no pain and urinary retention improved. Two months after surgery, he had made a complete recovery.

Clinical Report of New Cervical Orthosis “Neck-Chest brace”

Cervical orthoses are always used to treat neck diseases and injuries. In these diseases, the orthotic goals may be to relieve pain and to support the unstable spine.However cervical orthoses are not comfortable for patients with rigid fixation.Since 1990, we have used the “Neck—Chest brace” following surgery on the cervical spine (C2 or C3-C7).Features of this orthosis are:(1) This brace is very light (about 300g)(2) We are able to use this orthosis for patients confined to bed.(3) After cervico—thoracic fixation, we can use this as a collar.