Teriparatide Injections Can Improve Fusion Rates in Postmenopausal Women with Osteoporosis
A prospective trial was done to examine if teriparatide administration following instrumented lumbar posterolateral fusion would improve bone union in postmenopausal women with osteoporosis. Teriparatide was compared to the use of bisphosphonate after surgery.
This study was undertaken because while intermittent parathyroid hormone (PTH) treatment has been shown to increase bone mass and lower the risk of osteoporotic vertebral fractures, its efficacy in promoting spinal fusion has not been fully addressed. Pre-clinical data support its use.
Results of the study were published online August 6, 2012, ahead of print in Spine. The article is “Teriparatide Accelerates Lumbar Posterolateral Fusion in Postmenopausal Women With Osteoporosis: Prospective Study.”
In the study, there were 57 postmenopausal women with osteoporosis. All had been diagnosed with degenerative spondylolisthesis, and they were split into two treatment groups. The teriparatide group (n = 29) received daily subcutaneous injections of 20 μg teriparatide. The bisphosphonate group (n = 28) received a weekly oral administration of 17.5 mg risedronate.
Regardless of the group, all patients underwent decompression and 1- or 2-level instrumented posterolateral fusion. Local bone graft was used in all surgeries. One year after surgery, fusion rate, duration of bone union, and pain scores were evaluated for both groups.
Study Results Comparing Teriparatide and Bisphosphonate
One year post-operative, the two groups both showed improvement in pain scores, and there was no significant difference between the groups.
The rate of bone union did show a difference: in the teriparatide group, it was 82%, and in the bisphosphonate group, it was 68%. Average duration of bone union also differed. The average was 8 months in the teriparatide group, but it was 10 months in the bisphosphonate group.
Daily Subcutaneous Teriparatide Injection Superior
This study showed that in postmenopausal women with osteoporosis who undergo instrumented lumbar posterolateral fusion, daily subcutaneous injections of teriparatide provide better bone union rates than weekly oral administration of bisphosphonate.