back pain red flags
Last edited 06/2022 and last reviewed 06/2022
Red Flags for Lower Back Pain
General Principles of Red Flags for Back Pain:
The UK Royal College of Emergency Medicine (RCEM) define Red Flags for back pain as:
- non-mechanical back pain
- past history of cancer, steroids, HIV
- generally unwell
- unexplained weight loss
- widespread neurological symptoms or signs
- structural deformity
- thoracic back pain
The RCEM note the TUNA FISH mnemonic for considering red flags for back pain:
Red Flags can be considered in terms of presenting features or particular conditionsIn terms of presenting features (1,2,3):
Factors in the history include:
- cancer
- unexplained weight loss
- history of immunosuppression
- history of HIV or tuberculosis
- prolonged use of steroids
- intravenous drug use
- urinary tract infection
- pain that is increased or unrelieved by rest
- fever
- history of atherosclerotic vascular disease
- significant trauma related to age (e.g. fall from a height or motor vehicle accident in young patient, minor fall or heavy lifting in potentially osteoporotic or older patient or a person with possible osteopororosis)
- bladder or bowel incontinence
- urinary retention (with overflow incontinence)
- consider age of patient in context of presentation of back pain - a review noted that back pain <20 years was significant (4); as is back pain in > 50 years old
Factors on examination:
- saddle anaesthesia
- loss of anal sphincter tone
- major motor weakness in lower extremities
- fever
- vertebral tenderness
- limited spinal range of motion
- neurological findings persisting for more than one month
- palpable pulsatile abdominal mass ? possible abdominal aortic aneurysm
Possible cancer red flags include:
- history of cancer - some cancers are known to metastasise to bone
- primary tumours which give rise to metastases to bone are remembered by many students by the nonsense rule that they all begin with a B. Thus:
- breast
- bronchus
- byroid (thyroid)
- bidney (kidney)
- bostate (prostate)
- (rarely, bowel)
- however note that pancreatic cancer can present with back pain (see below)
- unexplained weight loss
- unintentional weight loss is loss of 10 pounds (4.5 kilograms) or 5% of your normal body weight over 6 to 12 months or less without knowing the reason (5)
- age over 50 years
- night pain that disturbs sleep
- no improvement in back pain symptom in a 4-6 week period despite conservative therapy
- back pain at rest
Possible infectious cause of back pain red flags include:
- persistent fever
- history of intravenous drug misuse
- history of lumbar spine surgery within the last 12 months
- recent bacterial infection e.g. pyelonephritis, cellulitis, pnemonia
- history of tuberculosis
- immunocompromised state e.g. history of use of systemic steroids, organ transplant, HIV, diabetes mellitus
Cauda Equina Syndrome Related Red Flags include:
- urinary incontinence (occurs because of loss of sensation that passing urine)
- urinary retention (occurs because loss of sensation of bladder fullness)
- saddle anaesthesia
- faecal incontinence
- decreased anal sphincter tone
- bilateral lower extremity weakness or numbness
- progressive neurological deficity
- major motor weakness - such as major motor weakness with knee extension, ankle eversion, or foot dorsiflexion.
- major sensory deficit
Vertebral Fracture related red flags include:
- prolonged use of systemic steroids
- history of trauma
- the severity of trauma where a vertebral fracture may occur varies with various factors such as age, co-morbidities and use of corticosteroids. Thus in an elderly patient with osteoporosis then a vertebral fracture might occur with minimal trauma or even after heavy lifting. In a young patient with no osteoporosis and no corticosteroid use then a vertebral fracture might occur after a significant trauma such as falling from a height onto a hard surface
- localised vertebral tenderness
- a structural spinal deformity e.g. a step deformity
Also consider a possible abdominal aortic aneurysm or pancreatic cancer in the patient with back pain.
AAA possible features include:
- pulsating abdominal mass
- past history of atherosclerotic vascular disease
- pain at rest or nocturnal pain
- age greater than 60 years
Pancreatic cancer possible features include (6):
- typically patients complain of a deep epigastric pain, which in 60% of cases, radiates to the back
- unexplained weight loss - due to anorexia or malabsorption
- pain at rest
- nocturnal pain
Reference:
- https://www.rcemlearning.co.uk/ (RCEM learning accessed 15/6/22)
- NICE (October 2020). Low back pain and sciatica in over 16s: assessment and management
- Bratton RL. Assessment and Management of Acute Low Back Pain. Am Fam Physician. 1999 Nov 15;60(8):2299-2306
- ARC - Reports on Rheumatic Diseases (1999), 17, 1-4.
- National Library of Medicine - Medline Plus.Weight loss - unintentional (Accessed 23/4/2022).
- Bond-Smith G et al. Pancreatic adenocarcinoma. BMJ. 2012;344:e2476