[Influence of pedicle screws with different insertion depth on neighboring uninfused segments in a goat lumbar spinal fusion model].

Objective: To observe the influences of pedicle screws in various insertion depth on the adjacent segment disc degeneration following lumbar spinal fusion. To explore the relationship between the internal fixation rigidity and incidence of adjacent segment disease.

Methods: Sixteen hybrid male Bohr goats of 10 months old, weighting between 25 and 30 kg, were randomly devided into a control group (N group), and 3 experimental groups, each group had 4 goats.