[Analysis of the axial stretching force of the small splint fixation system].

OBJECTIVE: To measure the axial stretching force produced by the small splint fixation system in the treatment of the fracture.

METHODS: Dumbbell shaped plexiglass was machined to model the bone shaft with expanded two ends. Force transducer was set at the model fracture site to measure the stretching force produced by fracture fixation of the small splint with cloth aqueous bag that simulated the muscles and other soft tissue underneath.

RESULTS: There was positive relationship between the axial stretching force produced at the model fracture site and the transverse pressing force exerted by the external plates. The ratio of which was 1/10.

CONCLUSIONS: Muscle enwrapped with fascia is similar to the cloth aqueous bag system in mechanical structure. From this article, axial stretching force exists at the bone shaft fracture site when fixed by small splint which exerts the force transversely from the outside of the extrimity.