Controlled-Release Curcumin for the Treatment of Pain Related to Adult Degenerative Scoliosis: A Retrospective, Open-Label, Case-Controlled Series

It is estimated that the incidence of scoliosis in adult patients ranges from 32% to as high as 68% in postmenopausal females age 60 and up [1]. Adult patients with scoliosis often score worse on health related quality of life questionnaires compared to non-scoliotics [2]. Although Weinstein et al showed no statistical difference in quality of life among adult scoliotic and non-scoliotic patients, they did show a significant difference in chronic pain levels between the two groups [3]. Adult scoliosis patients are far more likely to seek therapeutic intervention for scoliosis due to pain when compared to adolescents [4]. Therefore, finding new ways to improve pain levels in this particular population, given the prevalence of scoliosis in postmenopausal females, is essential.


Introduction
It is estimated that the incidence of scoliosis in adult patients ranges from 32% to as high as 68% in postmenopausal females age 60 and up [1]. Adult patients with scoliosis often score worse on health related quality of life questionnaires compared to non-scoliotics [2]. Although Weinstein et al showed no statistical difference in quality of life among adult scoliotic and non-scoliotic patients, they did show a significant difference in chronic pain levels between the two groups [3]. Adult scoliosis patients are far more likely to seek therapeutic intervention for scoliosis due to pain when compared to adolescents [4]. Therefore, finding new ways to improve pain levels in this particular population, given the prevalence of scoliosis in postmenopausal females, is essential.
Curcumin is a natural therapeutic agent that has been tested for a variety of pain disorders, including diabetic neuropathy [5], burn pain [6], osteoarthritis [7][8][9], delayed onset muscle soreness [10], surgical incision pain [11], and post-operative pain [12]. It is thought that curcumin contains anti-nociceptive and anti-inflammatory properties [13,14]. Therefore, in cases of adult scoliosis, where the condition is chronic, there is often an inflammation-driven pain response as well as from asymmetrical mechanical loading on the supportive soft tissues [15]. Our present study looks at how the introduction of a controlledrelease version of supplemental curcumin in patients with adult scoliosis pain affects their pain levels following a short trial of the medication.

Materials and Methods
We reviewed the charts of patients who participated in a short trial of exercise-based scoliosis treatment. All patients presented with a history of adult scoliosis, and pain that was clinically determined to be associated with the scoliosis based upon physical exam findings. Inclusion criteria were as follows: 1) patient must have been 25 years old or older at the initiation of exercise therapy; 2) they did not have a history of neuromuscular, juvenile, or infantile scoliosis; 3) negative history of spinal fusion surgery; and 4) participated in a two-week course of exercise therapy at the same clinic. Patient files were excluded if they did not have a 6-month follow-up documented in the chart.
At the initiation of therapy, patients were given the option of including a controlled-release curcumin supplement (CurcuPlex CR, Xymogen, Inc.) for the purposes of mitigating exercise-based muscle soreness [10] and improving scoliosis-related osteoarthritis pain. Dosage for all subjects was 1 tablet twice daily, 10-12 hours apart. Half of our cohort decided to take the supplement, while half opted against it. All patients subsequently began a two-week exercise based therapy for scoliosis. All patients received the same types of exercises, which were adapted specifically to each patient's level of function as well as their particular curve patterns. Once the two weeks of therapy was completed, each patient was given a specifically prescribed set of home exercises to perform until the next follow-up. Following the conclusion of treatment, patients were instructed to report back to the clinic in 6 months for follow-up. At that time, all patients completed updated numerical pain rating scales, follow-up ranges of motion were recorded, and a follow-up scoliosis radiograph was obtained to evaluate curve correction from the exercises.

Results
The average age of the intervention group was 51 years, and 46 years for the control group. All of the patients in both groups were female patients. At baseline, the intervention group reported average QVAS scores of 60, while the control group reported 57. The average starting Cobb angle for patients taking the curcumin was 43°, and 37° for the control group. Improvements in both groups were observed following exercise therapy. Cobb angle changes were also similar across all curve types between groups. Cobb angles were improved in all groups by an average of 6°, with one patient in the intervention group and two in the control group maintaining their Cobb angle measurements at 6 months. Pain levels improved in all patients and controls. All but one patient saw their QVAS scores drop below 50 on follow up testing. This value is used as a differentiation between mild and moderate to severe pain [16]. The remaining patient who maintained a score above 50 (53) was one of the three whose curves did not change on follow up. The average pain score decrease in the intervention group was 22, while the control group improvement averaged 12.

Discussion
In both the control and intervention groups, the pre and posttreatment Cobb angle changed by about the same amount (6º). However, the intervention group received the additional treatment of oral controlled-released curcumin until follow-up. Therefore, there are two possible explanations for the observed difference in the pain scores, 1) the curcumin was responsible for the observed pain score improvements, or 2) the addition of the curcumin treatment may have created a placebo effect on the pain scores. Follow-up studies with a sham treatment would confirm one of these explanations.

Limitations
Although the study was controlled, it was retrospective in nature, so it cannot exclude selection and examiner bias. However, attempts to minimize these were taken. We selected consecutive patients who fit the inclusion criteria and did not meet the exclusion criteria. Second, the control group was not offered a placebo supplement. Therefore, some of these patients may have reported bigger placebo improvements had they taken a placebo capsule. Finally, the sample size is small, and without a power analysis it is impossible to determine how much of a change was required between the two groups comparatively to make those changes valid.

Conclusion
Two groups of adult patients with idiopathic scoliosis who completed a short course of chiropractic rehabilitation therapy were assessed six months later for Cobb angle and pain levels. One of the groups additionally took a proprietary controlled-release curcumin supplement until follow-up. At six month follow-up, the group taking the curcumin supplement reported greater improvements in pain scores compared to the control group.