The Golden Retriever Muscular Dystrophy motion capture project is lead in collaboration with Texas A&M vet school.
Dogs affected with muscular dystrophy have a lack of muscle dystrophin which is a vital protein. At 3 – 4 months, they show the following characteristics:
- low weight gain,
- tarsal overflexion (cow hocks),
- generalized weakness, especially for the pelvic limb,
- cardiac abnormalities,
- skeletal muscle atrophy
Affected dogs show signs of weakness and gait disorders from the youngest age, and the final diagnosis is based on a muscle biopsy. Physical disease is usually graded from I to III depending on the muscular atrophy. Most of grade III cases terminate in extreme weakness, infections and death at 6 – 12 months of age.
The aim of this study is to find consistent markers measurable with motion capture and which evidence and quantify the evolution of the disease. We are using a 38 marker set which covers the joints of the dogs likely to be affected in their motion by the disease.
The study currently focuses on the range of motion of the back limb segments which are supposed to be the more affected:
The hock, stifle and hip-femur angles are segmented step by step and then compared at different time points (t1 = 2 months, t2 = 4.5 months, t3 = 6 months). To allow comparison, all the data is normalized according to both the size of the dogs and their steps (from 0% to 100%).
The first results point out that, in comparison with normal dogs, the affected ones show a decreasing range of motion correlated with the grade of dystrophy.
The study will be continued with the Vicon motion capture system associated to a pressure pad walkway which will bring baropodometric information during the dog’s gait.