Kazuhito Minamitani

Simple bone cyst. Treatment by trepanation and studies on bone resorptive factors in cyst fluid with a theory of its pathogenesis.

Simple bone cysts were treated by trepanation. The technique consists of drainage of cyst fluid, lavage of the cystic cavity with saline, and the making of multiple drilling holes through the cortical and the medullary bone of the cyst wall. Injection of corticosteroid was omitted. In 11 cases treated by this method, the clinical outcome was good. Biochemical analyses of the cyst fluid showed bone-resorptive factors, i.e., prostaglandins, interleukin 1, proteolytic enzymes. Electrophoretic analysis of proteolytic enzymes in polyacrylamide gel containing sodium dodecyl sulfate and polymerized gelatin showed proteins with molecular weights of about 130,000, 92,000, 72,000, and lower than 50,000. Increase in such bone-resorbing activities seems to be one of the causative factors in simple bone cysts. The technique was effective in decompressing the internal pressure of the cysts, improving the blood flow through the medullary bone of the cyst wall, stimulating the periosteum to induce bone formation, and eliminating bone destruction.

Rapidly destructive arthropathy of the hip. Studies on bone resorptive factors in joint fluid with a theory of pathogenesis.

The mechanism of joint destruction in rapidly destructive coxopathy was studied by analyzing bone resorptive factors in the joint fluid. Prostaglandins were found to play a partial role in joint destruction. Some cases of rapidly destructive coxopathy revealed elevated levels of interleukin-1 beta (IL-1 beta) in the joint fluid. Electrophoretic analysis of proteolytic enzymes in polyacrylamide gel containing sodium dodecyl sulfate and copolymerized gelatin demonstrated that the resorptively active peptides have relative molecular weights (M(r)) of approximately 92,000, 72,000, and lower than 60,000. Cultured cells from synovia obtained perioperatively secreted matrix metalloproteinase 2 (MMP-2) with an M(r) of 72,000 and matrix metalloproteinase 3(MMP-3) with an M(r) of 57,000. Synovial cells from the patients with coxarthrosis secreted fewer proteolytic enzymes. Prostaglandins, IL-1 beta, MMP-2, and MMP-3 could act synergetically as promotors in the rapid destruction of the hip joint.

Results of surgical treatment of muscular torticollis for patients >6 years of age

From 1983-1989, 37 patients with muscular torticollis were treated surgically by partial resection of the distal portion of the sternocleidomastoid muscle. Of these, 19 patients who at surgery were greater than 6 years of age (average 11 years 2 months) were followed for greater than 1 year (average 2 years 2 months). Although both function and cosmesis were improved in all cases, scoliosis was a residual deformity in some cases, especially in girls.

Postoperative Results of Femoral Neck Fracture in Aged Patients Over 90 Years

From April 1992 to December 1998, osteosynthesis and prosthetic procedures were performed on 352 cases of femoral neck fractures and clinical examinations were performed on 30 cases (8.5%) over 90 years old. The 30 cases (2 males and 28 females) whose age ranged from 90 to 99 years (mean, 92.1 years) were followed up 2 weeks to 6.5 years (mean, 2.25 years) after surgery. One patient died 2 weeks after surgery, but 22 patients (84.6%) lived over 1 year after surgery and 17 patients (56.7%) were alive at the latest follow-up. Twenty one patients (70%) regained the ability to walk by the time of their discharge. In spite of early post-operative rehabilitation, the activities of daily living (ADL) at discharge were lower than that before injury due to senile dementia, celebral infarction, hemiplegia, or a major complication. In our cases osteosynthesis procedures for intracapsular femoral neck fractures produced a good prognosis and may better than prosthetic procedures in some cases.