The pathogenesis of chronic tendinopathy is unclear but it does not appear to be an inflammatory process. Apoptosis may lead to degenerate tissue through a nitric oxide-mediated pathway. Increased levels of nitric oxide have been demonstrated in Achilles tendinopathy.
Department of Trauma and Orthopaedic Surgery, Basingstoke and North Hampshire Hospitals, NHS Foundation Trust, Basingstoke, United Kingdom. chris.pearce@doctors.org.uk