Kenji Fukuda

A comparative study of chemonucleolysis with recombinant human cathepsin L and chymopapain. A radiologic, histologic, and immunohistochemical assessment.

STUDY DESIGNnInvestigation of the effects of recombinant human cathepsin L on intervertebral discs and comparison with the effects of chymopapain.nnnOBJECTIVEnTo evaluate the effects of cathepsin L on intervertebral discs as an agent for chemonucleolysis.nnnSUMMARY BACKGROUND DATAnCathepsin L is a typical cysteine proteinase that belongs to the papain superfamily. It plays a major role in intracellular proteolysis and is not believed to induce anaphylactic reactions.nnnMETHODSnIn vivo: Rabbit intervertebral discs were injected with recombinant human cathepsin L, its buffer solution, and chymopapain. After 1, 4, and 16 weeks the animals were killed, and radiologic and histologic examinations were performed. In vitro: The enzymatic actions of recombinant human cathepsin L and chymopapain on human intervertebral disc proteoglycans were examined immunohistochemically using antiproteoglycan antibodies.nnnRESULTSnIn rabbit models, roentgenography showed that disc spaces treated with cathepsin L and chymopapain had become narrower 1 week after injection. Histologically, loss of safranin-O staining was observed in the anulus fibrosus of discs treated with cathepsin L. After 16 weeks, nucleus pulposus had regenerated with chondrocyte-like cells, and the safranin-O staining characteristics of the matrix also had recovered. In an immunohistochemical study, all components of the proteoglycan stained weakly after chymopapain digestion. After cathepsin L digestion, unsulfated chondroitin and core protein staining was weaker, but the chondroitin 6-sulfate staining was unaffected.nnnCONCLUSIONSnCathepsin L seems to be an effective agent for chemonucleolysis. Its enzymatic action on proteoglycan appears to be different from that of chymopapain.

Treatment of Cases of Synovial Sarcoma

We experienced 5 cases of synovial sarcoma of the lower extremity from 1990 to 1994.All patients were treated with adjuvant chemotherapy and surgical treatment. CDDP, ADR, IFO, CBDCA, CYVADIC and HD-MTX were used for adjuvant chemotherapy, protocols. One case treated with a BK amputation and CDDP and another case treated with limb salvage and CDDP, ADR, IFO were judged to be successful. One case received CDDP, ADR, IFO and an AK amputation. Two months later enlargement of their metastatic lung tumor was noted, so adjuvant SYVADIC was started. 3 weeks later, the tumor size was diminished, and this response was judged to be a PR.

Laminoplasty for Cervical Spine Lesions

Since 1984, cervical spinal canal enlargement has been performed in 33 patients with cervical myelopathy (21 with cervical ossification of the posterior longitudinal ligament and 12 with cervical spondylosis). In expansive open-door laminoplasty, the average age at surgery was 57.5 years and the average follow-up period was 4 years and 5 months. In double door laminoplasty, the average age at surgery was 65.3 years and the average follow-up period was 1 year and 2 months. Clinical results were evaluated using JOA score for cervical myelopathy and recovery rates using Hirabayashis method. In expansive open-door laminoplasty the preoperative average score was 8.7 points, and this improved to 12.2 points postoperatively. The average recovery rate was 42.2%, In double door laminoplasty the average preoperarve score was 8.1 increasing to 11.6 postoperatively The average recovery rate was 39.3%. Radiologically, cervical alignment showed a tendency to be straight, and postoperative cervical antero-posterior movement decreased. Cervical laminoplasty is a useful procedure for treatment of cervical myelopathy.

Functional Prognosis after Limb Salvage Operation for Malignant Bone Tumors of the Lower Extremity

Limb salvage operation was performed in five cases of malignant bone tumors of the lower extremity. All cases were reconstructed using a Kotz prosthesis and the postoperative function was evaluated according to Ennekings criteria. As a result, three cases were rated as fair and two cases were rated as poor. The main reason for the unsatisfactory results was insufficiency in muscle strength for knee extension. Regarding complications, there were three cases of skin necrosis, one case of local recurrence and two cases of lung metastasis.