Safety and Efficacy of Botulinum Toxin A in Children Undergoing Lower Limb Lengthening and Deformity Correction: Results of a Double-blind, Multicenter, Randomized Controlled Trial.

BACKGROUND: Lengthening of the lower limb is a complex procedure in which pain management and complications such as pin-site infections and muscle contractures impact the family and affect the child's quality of life. As a result, the paralytic and antinociceptive actions of neurotoxins may be indicated in managing these complications; however, few studies have explored ways to improve outcomes after lengthenings. The objective of this study was to evaluate the safety and efficacy of botulinum toxin A (BTX-A) in children undergoing lower limb lengthenings and deformity correction. METHODS: Participants with a congenital or acquired deformity of the lower extremity requiring surgery to one limb were randomized to receiving either BTX-A as a single dose of 10 units per kilogram body weight, or an equivalent volume of saline solution. Pain, medication, quality of life, and physical function were assessed at different time-points. Adverse events were recorded in all participants. T test and χ tests were used to compare potential differences across both groups. RESULTS: Mean age of the 125 participants was 12.5 years (range, 5 to 21 y), and lengthenings averaged 4.2 cm. Maximum pain scores on day 1 postoperatively were lower in the BTX-A group (P=0.03) than in the placebo group, and remained significant favoring botox when stratifying by location of lengthening (femur vs. tibia). Clinical benefits for BTX-A were found for 3 quality of life domains at mid-distraction and end-distraction. When stratifying according to location of lengthening, there were significantly fewer pin-site infections in the tibia favoring botox (P=0.03). The amount of adverse events and bone healing indices were no different in both groups. CONCLUSIONS: The clinical differences in quality of life, the lower pain on the first postoperative day, and the lower number of pin-site infections in the tibia favoring BTX-A support its use as an adjunctive treatment to the lengthening process. The detailed analyses of pain patterns help inform families on the pain expectations during lower limb lengthenings. The amount of adverse events were no different in both groups, and bone healing rates were similar, indicating that the use of BTX-A in children undergoing limb lengthening and deformity correction is safe. LEVEL OF EVIDENCE: Level I.

Botulinum toxin type A injection in alleviating postoperative pain and improving quality of life in lower extremity limb lengthening and deformity correction: a pilot study.

BACKGROUND: The Ilizarov technique is commonly used for lengthening and deformity corrections of the lower limbs in children. Postoperative pain can be significant, affecting quality of life and functional mobility, and often requiring prolonged medication use. Several studies have investigated the antinociceptive actions of botulinum toxin type A (BtX-A), yet evidence for its use in this population is limited. The objectives were to (1) establish the feasibility of a randomized clinical trial in children undergoing limb lengthening or deformity correction and (2) provide preliminary evidence of the beneficial effects of BtX-A in this population. METHODS: Fifty-two patients with a mean age of 13.7 years (range, 5 to 21 y) were randomized to receive either BtX-A or an equivalent volume of sterile saline solution (placebo group), as a single dose during the surgical procedure. Pain, medication use, quality of life, and functional mobility outcomes were assessed in all patients. Adverse events were reported for all patients and classified as minor or major. RESULTS: Differences between groups did not reach statistical significance; however, pain at mid-distraction was found to be slightly lower in the BtX-A group, as compared with the placebo group. Patients in the BtX-A group used less parenteral pain medication in the first 4 days after the surgery, had higher quality of life scores at 3 of the 5 time points assessed, and slightly higher functional mobility scores. All adverse events were expected complications of the lengthening process. No event was considered to be a serious adverse event related to the BtX-A injection itself. There was a trend toward fewer major adverse events in the BtX-A group. CONCLUSIONS: This pilot study established the feasibility of a randomized controlled trial design for in this population. Its findings indicate that BtX-A injections appear to be safe and effective for reducing pain and improving the quality of life and functional mobility of children undergoing lengthening or deformity corrections of the lower limbs. A larger-scale study is currently underway to confirm these preliminary findings.