Abnormal Foot Progression Angle Kinematics in Cervical Dystonia Improved After Osteopathic Manipulative Medicine: A Prospective Case Series

Introduction Cervical dystonia (CD), a rare disorder, is the most common form of dystonia, a movement disorder. Impairments in activities of daily living and quality of life may result from chronic pain, perceived stigma, difficulty walking, and/or lack of control over movements. Studies of treatments for difficulty walking in CD have been inconclusive. Osteopathic manipulative medicine (OMM) has been used to improve gait biomechanics in other health conditions. Foot progression angle (FPA) while walking indicates functional gait abnormalities that increase the risk of knee injury and osteoarthritis. Objective The aim of this study is to test if five-weekly treatments using an OMM sequence designed for CD improved abnormal gait biomechanics in individuals with CD by identifying and addressing somatic dysfunctions. Methods In this prospective case series, independently ambulating individuals with CD symptom onset before the age of 40 years, not due to traumatic injury, were evaluated utilizing validated scales for severity (Toronto western spasmodic torticollis rating scale [TWSTRsI]) and symptoms affecting quality of life (Cervical Dystonia Impact Profile [CDIP-58]), physical examination, and FPA before and after five-weekly OMM treatments. Lower body joint range of motion and angles were captured in a clinical gait lab by nine cameras collecting three-dimensional Whole-body position data during three trials of one gait cycle at participant-selected walking speed. The FPA waveforms during the gait cycle were quantified by Vicon Nexus and Polygon applications. Pretreatment and posttreatment results were compared to established healthy gait waveforms and tested by repeated measures ANOVA (α=0.05). Results Pretreatment waveforms in CD had a mean 5.13° of excess FPA during gait cycle phases requiring lower-extremity pronation compared to previously published age-gender-matched healthy waveforms. There was 96% improvement in pronation after five treatments, with a mean 0.21° (p=0.041) of excess FPA. Mean TWSTRs and CDIP-58 scores improved. On physical examination, the rotational direction of C2 vertebrae was contralateral to neck muscle hypertonicity. Vertical sphenobasilar synchondrosis strains were present in those with anterotorticollis. Participants had ipsilateral anterolateral neck muscle and anterolateral abdominal wall muscle hypertonicity. All patients had pelvic somatic dysfunctions with left-side superior relative to right-side and restriction from lower-extremity pronation (i.e., supination dysfunctions). Conclusion The FPA was significantly improved after treatment. This OMM sequence was well tolerated and may be useful for improving gait kinematics in individuals with CD. Randomized, controlled, long-term studies are needed to determine effectiveness.