Methods: Seventy-five patients who underwent BKP in our institution participated in this study; 49 provided follow-up data. Those with complications and persistent pain were assigned to the “eventful” group; the others, to the “uneventful” group. We evaluated risk factors for complications and persistent pain, including the presence or absence of severe posterior wall injury/pedicle fracture, the shape of the vertebral body, and the time period from onset of pain to BKP. Results: The incidences of severe posterior wall injury, pedicle fracture, and flattened vertebral body did not differ significantly between the uneventful and eventful groups. However, there was a significant difference in disease duration between those with and those without adjacent vertebral fractures (AVFs): The incidence of AVF was lower among patients with disease of less than 8 weeks’ duration. Conclusions Disease duration is a possible risk factor for developing AVF, whereas other characteristics were not risk factors for complications after BKP. Although it has been suggested that BKP treatment in the early phase after injury results in a good outcome, the indications should be determined according to prognosis that is based on findings obtained with tools such as imaging examinations.