Special Poster Session 50th International Society for the Study of the Lumbar Spine Annual Meeting 2024

Introduction: Conservative treatment has been suggested as the first-line management for osteoporotic vertebral fractures (OVF), and surgical treatment such as vertebroplasty or decompressive fixation has been recommended in cases of nonunion or delayed paralysis that occurred despite conservative treatment. However, recent studies have shown that shortening the period of bed rest, as recommended in the treatment of proximal femoral fractures, can maintain quality of life and extend a healthy lifespan. Therefore, this study investigated the efficacy of early posterior percutaneous pedicle screw fixation (PPSF) in acute OVF patients without severe vertebral instability but with posterior wall damage for achieving early ambulation and restoring the activity of daily living (ADL).

Methods: A total of 73 OVF patients (38 women; mean age, 71.4±8.9 years) with a posterior wall injury but without an intravertebral vacuum cleft on computed tomography imaging who underwent surgical treatment within 28 days after the injury were included. Other inclusion criteria were age≧65 years old or a femoral neck bone mineral density <80% of the young adult mean. The exclusion criteria were symptomatic spinal canal stenosis requiring decompression, metastasizing malignancy, ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis. All subjects were treated with PPSF at our hospital. Postoperatively, each was transferred to a wheelchair or underwent early gait training using a walker starting at 2 days post-operation according to pain tolerance. Each patient was followed up for at least 2 years post-operation. The primary study investigated the change over time in wedge angle and vertebral collapse ratio of the fractured vertebra. The secondary study compared the incidence of subsequent vertebral fractures of early PPSF group with that of conservative treatment group (n=115), consisting of OVF patients treated conservatively from our multicenter osteoporotic fracture database named STOP-Fx study, or the late posterior pedicle screw fixation group (n=74), who received surgical treatment after at least 28 days of conservative treatment.

Results: The bone union rate was 97.2% (71/73). No additional revision surgery and no other complications such as surgical site infection and rod fracture after the procedure were observed. The preoperative mean wedge angle and vertebral collapse ratio of 17.1 degrees and 39.1%, respectively, improved to 9.8 degrees and 21.9% immediately after surgery. At the last observation, these values were 12.7 degrees and 28.7%, respectively. The instrumentation was removed in 41 patients after successful bony union was achieved. The incidence of subsequent vertebral fractures was 5.8% in the early PPSF group, 10.4% in the conservative treatment group, and 31.1% in the late posterior fixation group.

Discussion: Early PPSF for OVF with a posterior wall injury resulted in an excellent bone union rate and the prevention of a vertebral wedge angle beyond that at the time of the injury. Moreover, it significantly prevented the incidence of subsequent vertebral fractures, which could ultimately lead to a maintened spinal alignment. Furthermore, early PPSF for OVF could maintain their ADL, suppress muscle weakness, and to prevent dementia by enabling patients to leave the bed early.