Summary
Definition
Acute pain is a common consequence of injury or illness, generally lessening shortly after onset and resolving once healing is complete. Since healing occurs over a maximum of 3 months, pain persisting longer than 3 months is deemed chronic pain or persistent pain. Chronic pain may also occur in patients with ongoing degenerative illnesses, such as rheumatoid arthritis, or other chronic conditions, like migraine or neuropathic pain. Neuropathic pain is characterised by allodynia and hyperalgesia. Allodynia is the perception of non-noxious stimuli as painful. In hyperalgesia, noxious stimuli produce exaggerated or prolonged pain. Pain severity may fluctuate in patients with chronic pain, with times of increased pain or pain flares occurring either in relation to increased activity or stress, or insidiously. Chronic pain occurs due to persistent activation of neural pain pathways and muscle spasm. Chronic pain is discussed here as a syndrome and includes non-malignant conditions without localised or regional causes (such as abdominal pain or pelvic pain).
[Figure caption and citation for the preceding image starts]:
Acute pain occurs with trauma or illness, decreasing during healing and resolving within 3 months. Chronic pain persists after healing is completed, due to continued activation of neural pain pathways and muscle spasm
From Marcus DA. Headache and chronic pain syndromes. The case-based guide to targeted assessment and treatment. Totowa, NJ: Humana Press; 2007
[Citation ends].
History and exam
Key diagnostic factors
- presence of risk factors
- duration of pain more than 3 months
- physical comorbidity
- psychological comorbidity
- previous history of acute pain episodes
- pain causing difficulty in performing routine activities of daily living
- precipitating factors for myofascial pain
- precipitating factors for musculoskeletal pain
- herpes zoster infection
- history of trauma or limb immobilisation
- analgesic use
- muscle spasm
- associated somatic symptoms
- muscle tenderness to palpation
- trigger-point tenderness
- taut bands
- twitch response
- joint swelling and tenderness
- tender points
Other diagnostic factors
- precipitating factors for chronic headache
- headache pain lasting less than or more than 2 hours
- radiating pain
- morning stiffness in joints
- pain with prolonged walking, relieved with stooping or sitting
- joint pain
- burning quality of pain
- allodynia
- hyperalgesia
- chronic headache associated with nausea, vomiting, and sensitivity to light and noise
- intermittent pattern of chronic headache pain
- bilateral chronic headache pain
- unilateral chronic headache pain
- limited ROM
- painful or limited straight leg raising
- shoulder girdle and pelvic girdle pain distribution
- symmetrical body pain distribution
- worsening headache symptoms despite treatment
- headache with posterior head or neck pain
- excessive guarding of the painful extremity
- diminution or loss of reflexes
- tenderness over temporal artery distribution
Risk factors
- age over 45 years
- female sex
- pregnancy
- history of trauma or chronic pain
- FHx of chronic pain syndromes
- acute back pain with neurological signs
- high-risk occupation
- comorbid personality/psychological distress
- pain-related disability
- cigarette smoking
Diagnostic investigations
Investigations to consider
- plain x-rays of spine, bones and joints
- MRI of spine
- EMG and nerve conduction studies
Treatment algorithm
Contributors
Authors VIEW ALL
Consultant, Pain Medicine and Anaesthesia
North Bristol NHS Trust
Bristol
UK
Disclosures
GC has been sponsored by Boston Scientific, St Jude Medical, and Nevro to attend cadaveric workshops relevant to neuromodulation.
Dr Gaurav Chhabra would like to gratefully acknowledge Dr Sarah Love-Jones and Dr Dawn A. Marcus, previous contributors to this monograph. SLJ has received consultancy fees for Boston Scientific and Nevro Corporation (regarding spinal cord stimulation) and is an Elected Council member of the British Pain Society. DAM is an author of a reference cited in this monograph.
Peer reviewers VIEW ALL
Clinical Instructor
Department of Anesthesiology
University of Washington School of Medicine
Seattle
WA
Disclosures
JDS declares that he has no competing interests.
Consultant in Pain Management
Pain Unit
King's College Hospital
London
UK
Disclosures
JH has chaired advisory boards for Napp Pharmaceuticals Ltd., chaired a symposium, is a principle investigator and has participated in advisory boards for Grunenthal Ltd., and has given lectures for Pfizer Ltd. JH has also attended the American Pain Society meeting in 2009 sponsored by Grunenthal.
Consultant in Pain Medicine
Pain Management Service
University Hospitals of Leicester
Leicester
UK
Disclosures
Not disclosed.
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