1304 - The Rodeo of Dystonia: When Bulls Leave More Than Just a Mark

Case Diagnosis: Focal Dystonia

Case Description: A 75 year old man with a 2 year history of left foot dystonia that developed after a bull struck him, causing traumatic injuries to the posterior cruciate ligament, and EMG confirmed peroneal nerve injury. He initially had left ankle eversion and dorsiflexion weakness, then developed focal dystonia in his foot where his foot would go into plantarflexion and inversion when his legs were crossed. His left fibular head was also noted to have increased laxity relative to the right. The dystonia would resolve with forced repositioning of the ankle to a neutral position (geste antagoniste/trick maneuver); pathognomonic of dystonia.



The symptoms were managed with a peroneal nerve decompression, subsequent ultrasound guided scar hydrodissection, and ankle foot orthosis. Additionally, a trial of Onabotulinum toxin injections was attempted but failed to control the dystonia. A subsequent trial of Abobotulinum toxin was performed to treat his dystonia, with response pending.



Discussions: Whether or not peripheral nerve injury can cause dystonia has been a long-debated topic. Previous widely used criteria, although unvalidated, established that dystonia can be attributed to peripheral nerve injury if symptoms present within 1 year of injury. There have been other studies supporting the possibility of peripheral nerve induced dystonia.


Conclusions: In a patient with a significant history of leg trauma and surgeries, the enduring dystonia is puzzling.The discovery of loose fibular head mobility adds complexity to understanding the etiology of dystonia in this complex patient. It is plausible that the unusual fibular head movement is a trigger for this patient’s dystonia. This case highlights the understanding of dystonia in patients with extensive leg-related trauma and interventions.