Red flags

GGC MSK foot and ankle
NHS GGC

The primary aim of the patient assessment and differential diagnosis is to exclude any serious pathology through screening for red flags.

It is important to bear in mind that red flags represent a list of clinical findings rather than a set of diagnostic labels. They raise an index of suspicion with regard to sinister pathology. It is only after clinically reasoning all assessment findings that a clinical diagnosis should be made. It is also important to retain a sense of perspective when examining patients as only 1% of examined patients are suspected of having a serious pathology. It is vital to look at the patient from a holistic perspective and consider the context of each finding in light of other findings.

Red Flags: are essentially clinical prediction guides: they are not diagnostic tests and they are not necessarily predictors of diagnosis or prognosis. The main role of red flags is that when combined they help to raise the clinician’s index of suspicion.

Where a patient is failing to respond to conservative management re-screening for red flags should be repeated.

If serious pathology is suspected discuss with senior colleague or clinical specialist for potential ONWARD REFERRAL referral as required.

Possible red flags that may indicate serious pathology are:

  • History of cancer
  • Weight loss
  • Thoracic pain
  • Trauma
  • Widespread neuro changes

The Red Flag indicators of serious pathology include:

  • A past history of cancer
  • Unexplained weight loss (>10kg body weight in 3 months)
  • Non-mechanical and/or night pain
  • Intractable or increasing pain
  • Osteoporosis
  • Abnormal bladder and bowel symptoms
  • Violent trauma
  • Progressive widespread neurological signs.  Unilateral or bilateral Ul/LL weakness and/or weakness extending over several dermatomes
  • Systemically unwell, infection, fever, high pulse
  • Severe acquired structural deformity
  • Peripheral neuropathy with rapid structural changes – consider Charcot

For guidance on patients with suspected Serious Pathology, see the relevant sections below.

Cauda Equina

Signs and symptoms

  • Dysfunction of bladder, bowel or sexual function
  • Sensory changes in saddle or peri-anal area
  • Gait disturbance

Pain may be wholly absent; the patient may complain only of lack of bladder control and of saddle anaesthesia.

Next stepsPatient to contact NHS24 for advice

Cancer or tumour

Signs and symptoms

  • Atypical mass / swelling with or without the presence of pain
  • Pain with no history of injury
  • Unremitting or increasing pain
  • Weight loss
  • Past medical history of Cancer
  • Systemically unwell
  • Night pain and disturbed sleep

Next steps

Urgent referral to orthopaedics or GP

Significant trauma of skeletal injury/dislocation

Signs and symptoms

  • Loss of movement + abnormal shape / deformity
  • Un-resolving pain over site
  • Reduced active and passive movement
  • Red, swollen, bruised
  • Minor trauma (history of osteoporosis)

Next steps

Patient to contact NHS24 for advice.

Suspected deep vein thrombosis

Signs and symptoms

  • Oedema at calf
  • Red, hot limb
  • Painful -often behind the knee but not in all cases
  • Feet cyanosis deep red/purple

Next steps

Patient to contact NHS24 for advice.

Septic arthritis

Signs and symptoms

  • Severe joint pain, usually in just 1 joint, sudden onset.
  • Swelling around a joint.
  • The skin around a joint has changed colour.
  • Patient is generally unwell and may have a high temperature or feel hot and shivery.

Next steps

Patient to contact NHS24 for advice.

Suspected Charcot

Signs and symptoms

  • Red, hot swollen foot
  • Neuropathy
  • Unexpected pain in neuropathic foot
  • Sudden change in foot shape

Next steps

Urgent referral to diabetes foot service or patient to contact NHS24 for advice.

Sepsis

Signs and symptoms

  • known or suspected infection
  • acting confused
  • slurred speech or not making sense
  • blue, grey, pale or blotchy skin, lips or tongue – on brown or black skin, this may be easier to see on the palms of the hands or soles of the feet
  • a rash that does not fade when you roll a glass over it
  • difficulty breathing, breathlessness or breathing very fast

Next steps

Sign post to A&E or call 999.

Editorial Information

Last reviewed: 13/11/2024

Next review date: 30/11/2025

Author(s): John Tougher, Laura Barr, Nikki Munro.

Reviewer name(s): John Tougher, Laura Barr, Nikki Munro.