Angela M. Taylor, DO
Comprehensive Neurorehabilitation & Spasticity Management Fellow
Medical College of Wisconsin
Milwaukee, Wisconsin, United States
John R. Mc Guire, MD
Professor PM&R
Medical College of Wisconsin
Milwaukee, Wisconsin, United States
Three cases of PPCD presented with severe intractable cervicalgia and cervicogenic headaches following whiplash injury with unremarkable neuro-imaging refractory to conservative myofascial treatments. Delayed symptom onset following the trauma was one week to eight months. Despite comprehensive work-up, PPCD was not identified for one to four years following the injury. Electromyography of several neck and trunk muscles revealed dystonic activity. Dystonia of the bilateral levator scapulae, pectoralis minor, and thoracic longissimus was present in all patients. Each case was successfully treated with BoNT every three to five months with dilution range one to four milliliters per 100 units. Case 1 had seven rounds of abobotulinumtoxinA with a total dose range 400-600 units. Case 2 had 13 rounds of onabotulinumtoxinA with total dose range 200-400 units. Case 3 had 11 rounds of incobotulinumtoxinA with total dose range 200-500 units. Treatment with BoNT demonstrated 50-100% symptom improvement for two to five months.
Discussions:
PPCD is not well-characterized and considered a rare and controversial diagnosis. PPCD differs from idiopathic CD in that the dystonia is fixed, lacks response to sensory tricks, and is reportedly less responsive to BoNT. This case series represents a subset of patients initially diagnosed with myofascial pain following the neck injury and found to have electrodiagnostic evidence of dystonia. These cases of PPCD had excellent response to BoNT without side effects. Several treatment sessions were needed to optimize BoNT dose and dilution.
Conclusions: PPCD should be considered in patients with post-traumatic cervicalgia who do not improve as expected with conservative interventions. BoNT is a safe and effective treatment option for these patients. Electromyography is necessary to identify problematic muscles and assist with analysis and dose titrations of BoNT in dystonia management.
