The gracilis muscle lies on the inner side of the hind leg and acts to pull the leg in. Fibrotic myopathy of the gracilis occurs when scar tissue forms in the muscle, causing an abnormal amount of tightness. It is not entirely clear what causes fibrotic myopathy (gracilis myopathy), but it may be due to trauma, repetitive low grade injury to the muscle, or genetic factors. Gracilis myopathy occurs more often in German Shepherds, particularly males. Fibrotic myopathy may be a simple (Mendelian) genetic disease in which a single mutation causes the condition.
Gracilis myopathy is often diagnosed quickly in our first session based on your dog’s gait. Dogs with this condition walk with a very distinct gait due to the tightness of the muscle. Affected hindlimbs have a shortened stride with a rapid, elastic internal rotation of the foot, external rotation of the tarsus, and internal rotation of the stifle during the swing phase. Palpation of the medial thigh reveals a characteristic firm taut band extending from the midline of the pelvis to the stifle. Palpation of the affected muscles may be painful. We often feel significant atrophy of the gracilis compared to the opposite leg.
Gait assessment and a hands-on exam of your dog by a rehab professional is often enough to diagnose gracilis myopathy. Ultrasound may assist in diagnosing this injury and extent of damage to the muscle belly. It also helps guide us as to when the muscle is completely healed.
Physical therapy is the primary treatment for gracilis myopathy. Surgical cutting of the muscle tendon can result in improved gait at first, but the scar tissue and tightness often returns after a few months. It is possible that rehabilitation after surgery could improve this outcome. If caught in the early stages of the disease, platelet rich plasma injections may also be helpful to stop the progression. Physical therapy for gracilis myopathy focuses heavily on stretching the contracted tissues and breaking up scar tissue. We use ultrasound, heat, shockwave therapy, laser therapy, massage, and stretching to try to loosen these tissues. We also address any secondary pain or swelling that may be associated with the fibrosis. We then slowly add in strengthening exercises. Exercises are focused on eccentrics, where we stretch the muscle bellies while contracting them. Our goal is to rebuild the gracilis muscle belly and get your dog back to walking with a more normal, symmetric gait.
