Evidence for neurogenic transmission inducing degenerative cartilage damage distant from local inflammation.

Objective: To investigate involvement of the nervous system in ipsilateral and contralateral joint inflammation.

Methods: Freund's complete adjuvant (CFA; 1 mg or 1 microg) was injected unilaterally and the messages (a) from the hind paw to the ipsilateral and contralateral knees and (b) from one knee to the contralateral knee were analyzed. The degenerative impact of the local injury on distant cartilage was assessed using patellar proteoglycan synthesis as an indicator.