pain can be classified as nociceptive (mechanical, inflammatory,ischaemic) peripheral, autonomic, and affective - obviously more than one mechanism may co-exist.
mechanical pain - due to mechanical force on nociceptors - eg lengthening or compressing tissue which contains nociceptors. Particular movements aggravate and ease - sometimes referred to as on/off pain.
Inflammatory nociceptors - due to injury to tissue, producing an inflammatory reaction. The release of chemicals into the tissues sensitivises the nociceptors and produces pain. Characterised by redness, oedema and heat. Diurnal pattern stiffness worse at night and in morning, benefitial effects of anti-inflammatory medication. Absense of trauma.
