History
Clarify:
- site and character of pain
- walking distance
- night pain
- stiffness
- ability to put on shoes and socks
- stairs, car transfer and bathing
- walking aids
- previous childhood hip disease or surgery
- infection history
- medical and social factors relevant to surgery
Pain from the lumbar spine, sacroiliac region, abdominal wall and knee can mimic hip disease.
Inspection and gait
Look for:
- antalgic gait
- Trendelenburg pattern
- fixed flexion posture
- scars
- muscle wasting
- leg-length discrepancy
Movement
Assess:
- flexion
- extension/Thomas test
- internal and external rotation
- abduction and adduction
Internal rotation is often lost early in osteoarthritis.
Leg length
Distinguish true from apparent discrepancy. Consider pelvic obliquity and fixed abduction/adduction deformity.
Separate:
- true bony length discrepancy
- apparent discrepancy due to pelvic obliquity/contracture
Clinical measurements should be correlated with imaging when planning reconstruction.
Special considerations in a painful arthroplasty
Ask specifically about:
- time from index surgery to onset of pain
- wound problems
- postoperative infection or antibiotics
- instability episodes
- clicking/squeaking
- start-up pain
- systemic symptoms
Complete the examination with spine, knee, pulses and neurological status when relevant.
Presentation
A concise FRCS summary should state:
- likely source of symptoms
- fixed deformities
- abductor function
- leg-length issue
- previous surgery
- whether there are red flags for infection or implant failure
Clarify the pain generator
Hip pain can arise from the joint, periarticular soft tissues, lumbar spine, sacroiliac region or referred sources. Groin pain is common in intra-articular disease, but location alone is not diagnostic.
Ask about:
- onset and progression
- walking distance
- start-up pain
- rest/night pain
- mechanical symptoms
- stiffness
- instability
- systemic symptoms
- previous childhood hip disease
- trauma and surgery
For an arthroplasty, chronology is particularly important: pain that never resolved after surgery suggests a different differential from a previously painless hip that later becomes painful.
Gait
Observe:
- antalgic shortening of stance
- Trendelenburg pattern
- trunk lean
- fixed flexion
- abductor weakness
- leg-length compensation
A Trendelenburg sign reflects failure of the abductor mechanism or inability to generate sufficient abductor moment. Causes include muscle/tendon failure, superior gluteal nerve dysfunction, altered hip biomechanics and painful inhibition.
Deformity and range
Assess:
- flexion
- fixed flexion with Thomas test
- internal/external rotation
- abduction/adduction
Loss of internal rotation is commonly an early feature of hip OA.
A fixed adduction deformity can produce apparent shortening; a fixed abduction deformity can produce apparent lengthening.
Painful THA examination
Look for:
- wound/sinus
- abductor weakness
- trochanteric tenderness
- instability signs
- leg-length change
- neurovascular deficit
Start-up thigh pain can raise concern for femoral component fixation problems, while groin pain can have acetabular, iliopsoas, infection or other causes.
No pain pattern alone is sufficiently specific to exclude infection.
Whole-patient examination
Assess:
- lumbar spine
- knee
- peripheral pulses
- neurology
- contralateral hip
This prevents an attractive radiograph from becoming the assumed pain source.
FRCS synthesis
A strong presentation should say what the likely pain generator is, whether there is fixed deformity, whether abductors function, whether length is abnormal and whether infection or implant failure remains a concern.