Real-world persistence of twice-weekly teriparatide and factors associated with the discontinuation in patients with osteoporosis.

INTRODUCTION: A 28.2 µg twice-weekly formulation of teriparatide (2/W-TPD) was developed to provide comparably high efficacy for osteoporosis to a 56.5 µg once-weekly formulation while improving the safety and persistence rate. In the current study, we aimed to elucidate the real-world persistence of 2/W-TPD and to identify the factors associated with the discontinuation of 2/W-TPD in patients with severe osteoporosis. MATERIALS AND METHODS: This retrospective study included 90 patients who were treated with 2/W-TPD at three hospitals in Japan. Patient information was collected, including age, sex, distance to the hospital, family structure, comorbidities, previous treatment for osteoporosis, timing of the injection, side effects and duration of 2/W-TPD treatment, barthel index (BI), and bone mineral density (BMD) of the lumbar spine and femoral neck. We examined the factors influencing 2/W-TPD discontinuation using the Cox proportional hazards model. RESULTS: The 12 month completion rate of 2/W-TPD therapy was 47.5%. The Cox hazard analysis identified side effects [Hazard Ratio (HR) = 14.59, P < 0.001], low BMD of the femoral neck (HR = 0.04, P = 0.002), and morning injection (HR = 3.29, P = 0.006) as risk factors influencing the discontinuation of 2/W-TPD. Other variables, including age, did not contribute to the continuation of 2/W-TPD. CONCLUSION: One year continuation rate of 2/W-TPD was higher than the previously reported value of the once-weekly formulation in real-world setting, probably due to the lower incidence of side effects. Introducing injection of 2/W-TPD may further improve the persistence of TPD therapy for osteoporosis.

18F-FDG-PET/CT localizes intervertebral disc space infection following posterior lumbar interbody fusion surgery leading to successful retention of percutaneously inserted pedicle screws: a case report.

INTRODUCTION: Postoperative infection is a potentially devastating complication of spine surgery and an appropriate strategy and timely decision-making are essential for successful treatment of deep surgical site infection (SSI) after spinal instrumentation surgeries. However, there is a lack of consensus on implant removal or retention. We report on a case of deep SSI after posterior lumbar interbody fusion (PLIF) surgery in which we achieved clinical cure by debridement and removal of the interbody fusion cage without removing the percutaneously inserted pedicle screws (PPS). CASE PRESENTATION: A case was a 53-year-old woman with deep SSI after PLIF surgery using the PPS system at the L4-5 level. Computed tomography (CT) showed no clear radiolucent line around the screws and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET)/CT demonstrated abnormal FDG uptake around the cages and no uptake around the pedicle screws. Intervertebral cages were removed and iliac bone grafts were inserted between the vertebral bodies, without removing the pedicle screws. The infection was cleared and bone fusion was achieved after the revision surgery. DISCUSSION: Targeting active infection using FDG-PET/CT is considered useful in narrowing the surgical margins and determining whether to preserve instrumentation in revision surgery after SSI. PLIF using the PPS system could be useful in preventing the easy spread of infection from the intervertebral space to the insertion point of PPS through the interstitial space.