A severe form of degenerative joint lesion (neuropathic arthropathy) is
known to complicate a variety of diseases that are associated with sensory
abnormalities. We studied the relationship between sensory deficits and the
development of degenerative joint lesions in dogs in two complementary
experiments. In Experiment 1, dogs that were subjected to unilateral
dorsal-root ganglionectomy (fourth lumbar to first sacral vertebra) failed
to show biochemical, gross, or histological evidence of degenerative joint
lesions in ipsilateral femoral condylar cartilage after sixteen months. In
Experiment 2, five of six dogs that were subjected to transection of the
anterior cruciate ligament two weeks after deafferentation of the
ipsilateral limb showed striking gross or histological lesions, or both, of
the femoral condylar cartilage three weeks after ligament transection (five
weeks after ganglionectomy). We concluded that the neuromuscular mechanisms
that protect normal joints from damage are inadequate to protect unstable
joints from becoming rapidly and severely damaged.