From: Neural and psychosocial contributions to sex differences in knee osteoarthritic pain
Terminology | Definition | Comments |
---|---|---|
Nociceptor | A sensory receptor that is capable of transducing and encoding a noxious stimulus | Nociceptors are located in a variety of tissue types including most structures of the articular joint |
Nociceptive neuron | A central or peripheral neuron that is capable of encoding noxious stimulation | Â |
Sensitization | Increased responsiveness of neurons to normal input or activation of a response by inputs that are normally subthreshold | Can occur in the periphery (nociceptors) or in the CNS pathway |
Primary hyperalgesia | Increased response to a stimulus that is normally painful | Occurs at the site of insult; results from peripheral nociceptor sensitization |
Secondary hyperalgesia | Increased response to a stimulus that is normally painful | Occurs outside the site of insult in tissue that is not injured; results from central neuron sensitization |
Allodynia | Pain due to a stimulus that does not normally evoke pain | Results from central neuron sensitization |
Temporal Summation | Increased pain to application of the same stimulus repetitively over a brief period of time | Enhanced in patients with osteoarthritis; surrogate measure of central neuron excitability |
Conditioned pain modulation | Application of a noxious stimulus distant to the test area (such as leg) produces analgesia (such as arm) | Decreased in patients with osteoarthritis; surrogate measure of central inhibition; also referred to as diffuse noxious inhibitory control (DNIC) |
Pain catastrophizing | Tendency to magnify the consequences of the pain and to feel helpless in managing the pain | Higher levels associated with higher OA pain, and worse outcomes (disability, pain) |
Self-efficacy | Â | Lower levels are associated with worse outcomes (function, pain) |
Fear of pain/movement | Excessive expectation that physical activity will worsen pain and function | Higher levels are associated with worse outcomes (function, disability, pain) |