ABSTRACT
Lumbar spondylolysis is a frequent cause of low back pain especially in adolescents involved in sporting activities. It is considered as a fatigue-type defect in the pars interarticularis or isthmus resulted from repetitive hyperextension and rotation on the spine; however, there is still confusion in regard to imaging findings of the location and direction of the defect. We report two unique cases of fifth lumbar spondylolysis in professional baseball hitter and adolescent pitcher; early-stage unilateral incomplete isthmus fracture and bilateral fracture in a different configuration, respectively. Computed tomography demonstrated vertical and more coronally oriented fracture lines compared with typical spondylolytic defect, and repetitive rotation in the same direction of pitching might cause a different type of fracture on the contralateral isthmus with the preexisting unilateral defect. Intriguingly, early-stage unilateral fracture in hitter was united after only 6 weeks of rest and rehabilitation and able to return to the game.
ABSTRACT
Atypical fractures associated with prolonged bisphosphonate (BP) therapy rarely occur outside the femur, and the diagnostic criteria, appropriate treatment principles, and fixation methods for atypical ulnar fractures have not been established. The authors experienced the use of internal fixation with a metal plate and a new internal fixation method with an intramedullary nail in the treatment of an atypical ulnar fracture in a patient who had been on BP therapy for 10 to 20 years. This paper reports findings along with a review of the relevant literature.