German Shepherd Fibrotic Myopathy Treated with Myectomy in Combination with Autologous Conditioned Plasma Therapy: A Case Series

Evaluated the outcomes in German Shepherd dogs diagnosed with fibrotic myopathy treated with myectomy followed by perilesional Autologous Conditioned Plasma (ACP) injections (n = 4). Fibrotic myopathy is an uncommon condition which can affect the infraspinatus, supraspinatus, iliopsoas, sartorius, gracilis, and semitendinosus muscles in dogs. This disease affects the functional length of muscles by replacing functional tissue architecture with an excess amount of fibrous connective tissue due to an unknown insult (muscle strain, immune-mediated, infectious, drug-induced, chronic vs. acute muscle injury, neurogenic, vascular anomaly). The prognosis of this disease has been poor due to the lack of effective treatment and the high incidence of recurrence. Myectomy and myotenectomy alone are often ineffective at preventing the reformation of fibrous tissue, and lameness typically recurs within 2 to 9 months once the muscle heals. Research of additional therapies to delay recurrent lameness and progression of disease include medical and surgical management (rest, anti-inflammatories, rehabilitation therapy, extracorporeal shock wave therapy, adipose-derived mesenchymal stem cells, myotenectomy, and myectomy). The purpose of this paper is to report the outcome of dogs diagnosed with fibrotic myopathy and treated with myectomy followed by ACP therapy. Scar tissue persisted and complete resolution of functional lameness was not achieved; however, the severity of the gait abnormality improved in all patient’s postsurgery and ACP therapy based on lameness grades and subjective owner assessment of mobility.

Acknowledgment

None.

Publication History

Article published online:
15 July 2025