The relationship between
pain/disability and angular deviation of the
hallux valgus (HV), and the impact of orthotic use, laterality, and
pain variability on treatment outcomes remain unclear. This was explored in post hoc analyses of a placebo-controlled trial of
abobotulinumtoxinA (aboBoNT-A; Dysport®) for HV-associated
pain (NCT03569098). The primary endpoint was not met in this study (change from baseline Numeric
Pain Rating Scale [NPRS] score vs placebo at week 8); however, there was a greater reduction from baseline in mean NPRS score at week 12 with aboBoNT-A 500U versus placebo (p = .06). Adults with painful HV without surgery were randomized (1:1:1) to aboBoNT-A 300U, aboBoNT-A 500U, or placebo. NPRS was completed for 7 days before baseline and weeks 4, 8, and 12. Over-the-counter
orthoses were permitted. Participants (N = 186) had a mean [standard deviation, SD] age of 48.2 [13.1] years, 18% (33/186) used orthotics, and 67% (124/186) had bilateral HV. No associations between baseline
pain severity and angular deviation were identified. Participants with high
pain variability at baseline (SD > 2) had a poorer response to aboBoNT-A treatment than those with less variability. In conclusion, no relationship between HV-related
pain/disability and angular deviation was observed. PLAIN LANGUAGE SUMMARY: A
bunion (medical term:
hallux valgus) is a common adult foot problem in which the big toe points inward toward the other toes, and this can be painful. How much the big toe points inward (how deformed the foot is) has been linked to the amount of
pain the patient experiences. A better understanding of this
foot deformity and
bunion pain will help doctors and patients to make the right treatment decisions. A study was completed looking at how
injections of a type of
botulinum toxin (
abobotulinumtoxinA) into specific muscles in the foot may help to reduce
bunion pain in patients without surgery. This subsequent analysis of the study data looked at the amount of
foot deformity in patients, the
bunion pain they experienced, and which factors affected how well
abobotulinumtoxinA worked to reduce
bunion pain. The results of this study showed that the amount of
foot deformity was not linked to the level of
bunion pain. When deciding the best treatment option to relieve
bunion pain, it is important that doctors not only consider how deformed the foot is, but also other important factors such as foot
pain levels.