Randomised placebo-controlled trial on the effectiveness of nasal salmon calcitonin in the treatment of lumbar spinal stenosis

Abstract

This is a double blind randomised controlled trial to assess the effectiveness of nasal salmon calcitonin in the treatment of lumbar spinal stenosis. The trial compared the outcome of salmon calcitonin nasal spray to placebo nasal spray in patients with MRI confirmed lumbar spinal stenosis. Lumbar spinal stenosis is one of the commonest conditions encountered by spine surgeons. It more frequently affects elderly patients and lumbar decompression has been used to treat the condition with variable success. Non operative measures have been investigated, but their success ranges from 15% to 43% in patients followed up for 1-5 years (Simotas in Clin Orthop 1(384):153-161, 2001). Salmon calcitonin injections have been investigated in previous trials and may have a treatment effect. Nasal salmon calcitonin has become available and if effective would have advantages over injections. Forty patients with symptoms of neurogenic claudication and MRI proven lumbar spinal stenosis were randomly assigned either nasal salmon calcitonin or placebo nasal spray to use for 4 weeks. This was followed by a 'washout' period of 6 weeks, and subsequent treatment with 6 weeks of nasal salmon calcitonin. Standard spine outcome measures including Oswestry disability index (ODI), low back outcome score, visual analogue score and shuttle walking test were administered at baseline, 4, 10 and 16 weeks. Twenty patients received nasal salmon calcitonin and twenty patients received placebo nasal spray. At 4 weeks post treatment there was no statistically significant difference in the outcome measures between the two groups. The change in ODI was a mean 1.3 points for the calcitonin group and 0.6 points for the placebo group (P = 0.51), the mean change in visual analogue score for leg pain was 10 mm in the calcitonin group and 0 mm in the placebo group (P = 0.51). There was no significant difference in walking distance between the two groups, with a mean improvement in walking distance of 21 m in the calcitonin group and 8 m in the placebo group (P = 0.78). At the end of the trial the ODI had improved by a mean of 3.7 points in the calcitonin group and 3.8 points in the placebo group (P = 0.44). This randomised placebo controlled trial has not shown any treatment effect in patients with lumbar spinal stenosis treated with nasal salmon calcitonin.