|Budget Amount *help
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1992: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1991: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1990: ¥1,100,000 (Direct Cost: ¥1,100,000)
Spinal instrumentations, which are made of stainless steel, play a significant role to stabilize the injured spines caused by trauma, tumors, degenerative diseases, and the other disorders. Those instrumentations have allowed patients to ambulate immediately after surgery. Thus, they can enjoy the good quality of life, even after big surgeries. Major disadvantages, however, are as follows; 1) Patients treated with spinal instrumentations (stainless steel) can not be examined with MRI (Magnetic Resonance Imaging), which is very useful in evaluating the neural tissues.:2) Spinal instrumentations, made of stainless steel, sometimes have to be removed two or three years after surgery. The purpose of this study are to evaluate the possibilities of spinal instrumentations, made of new artificial materials and to analyze the biomechanical properties of trunk muscle, which plays a important role after spinal stabilization surgery using spinal instrumentations. Results are as follows;
atible new materials such as chitin, polylactic acid, biodegradable high-molecule polymer, can be used for spinal instrumentations. Mechanical strength of the above materials, however, is inadequate for clinical use as spinal instrumentations. Stronger bioactive materials are now being evaluated.
2) From our clinical studies, spinal instrumentation made of titanium is now one of the best biocompatible ones for clinical use.
3) Trunk muscle strength is weaker in the patients with various spinal disorders than in the healthy subjects. This was true in the trunk muscle endurance. New methods for examining trunk muscle endurance are developed, modified with Kraus-Weber test and Sorensen test. Moreover, patients have the weaker trunk muscles in terms of both concentric and eccentric contraction. Trunk muscle proved to be quite important tissue for stabilize the spinal column as dynamic stabilizer.
4) Characteristics of flexion-relaxation phenomenon became clear. This phenomenon occurred only in patients with low-back pain.
5) On the next step, newer materials for spinal instrumentations and characteristic of trunk muscle have to be more analyzed. Less