GPs Dr Keith Hopcroft and Dr Vincent Forte look at adult hip pain – a common presentation in middle and old age – and offer advice on likely causes
Hip-area pain is a common presentation in older patients, which the patient often attributes to osteoarthritis. This diagnosis may well be correct, although the differential is wide. The possible diagnoses for the child with hip pain are very different, and are not covered here.
Differential diagnosis
Common
• Muscular/ligamentous strain
• Osteoarthritis
• Trochanteric bursitis
• Referred from back
• Meralgia paraesthetica
Occasional
• Inflammatory arthritis
• Avascular necrosis
• Hernia
• Complications of a total hip replacement
• Spinal stenosis
• Iliototibial band syndrome
• Acetabular labral tear
Rare
• Impacted fracture
• Dislocation
• Bony pathology – eg secondaries, Paget's disease
Possible investigations
Likely
X-ray
Possible
FBC, CRP, autoantibodies, HLAB27, alkaline phosphatase, urinalysis
Occasional
Arthroscopy, bone scan, lumbar spine MRI (all in hospital)
• X-ray: may show a variety of bony hip or spinal pathologies.
• FBC, CRP: CRP may be elevated and Hb reduced in inflammatory arthritis. CRP and WCC may be raised in infection of joint prosthesis.
• Autoantibodies: for clues about the aetiology of inflammatory arthritis.
• HLAB27: a high prevalence in spondoarthritides.
• Alkaline phosphatase: raised in Paget's disease.
• Urinalysis: may reveal proteinuria or haematuria if there is renal involvement in inflammatory arthritis.
• Arthroscopy: diagnostic and potentially therapeutic in labral tear.
• Bone scan: may reveal bony secondaries.
• Lumbar spine MRI: for evidence of spinal pathology.
Top tips
• Check what the patient means by ‘hip'. Most don't realise that the hip joint is actually in the groin.
• An X-ray may not be necessary, even if the clinical picture suggests hip arthritis – but the patient may well expect one, so ensure it is at least discussed.
• Examine the patient standing up – this may reveal a hernia as the cause.
• Localised lateral pain aggravated by lying on the affected side is likely to be caused by trochanteric bursitis.
Red flags
• Remember the possibility of loosening or infection in joint replacements.
• Consider avascular necrosis if a patient on long-term steroids develops hip pain.
• Beware that the elderly can sometimes remain weight bearing – albeit with pain and a limp – after an impacted hip fracture.
• Significant depression may aggravate or result from hip arthritis pain – consider a trial of antidepressants.
Dr Keith Hopcroft is a GP in Basildon, Essex
Dr Vincent Forte is a GP in Gorleston, Norfolk
