Why Hip Examination Is a High-Yield OSCE Station
The hip is the third most commonly examined joint in orthopaedic OSCE stations. Hip pathology — particularly osteoarthritis — is one of the most prevalent conditions in older adults in the UK. Hip examination stations also test your understanding of referred pain: hip disease commonly presents as knee pain, and knee disease can refer to the groin. Identifying this cross-referral is a common examiner question.
Setup
- Wash hands, introduce, confirm name and DOB, gain consent
- Expose both lower limbs from the waist down — maintain dignity with a sheet
- Ask about pain before touching: "Before I start, can you show me where the pain is?"
- Begin with the patient standing, then walking, then lying supine
Look — Inspect From Front, Side, and Behind
Standing:
- Pelvic tilt or obliquity (suggests leg length discrepancy or abductor weakness)
- Lumbar lordosis (increases with hip flexion contracture)
- Muscle wasting: gluteal wasting (posterior), quadriceps, calf
- Scars: posterior approach (lateral to buttock crease), anterolateral approach (lateral thigh)
- Deformity: external rotation of the leg at rest (fracture of neck of femur, OA)
Walking (gait):
- Antalgic gait: shortened stance phase on painful side
- Trendelenburg gait (lurching): trunk lurches toward the affected side on weight-bearing — indicates ipsilateral hip abductor weakness
- Short leg gait: functional leg length discrepancy
Feel
- Temperature: compare bilaterally
- Greater trochanter: tenderness = greater trochanteric bursitis (pain on lateral hip) or gluteal tendinopathy
- Inguinal ligament: tenderness medial to midpoint = hip joint; lateral = hip flexor (iliopsoas)
- Anterior hip joint: medial to femoral artery (lateral to pubic tubercle)
- Pulses: femoral, popliteal, dorsalis pedis (vascular referral and post-surgical assessment)
Move — Active Then Passive Range of Motion
| Movement | Normal range | Clinical note |
|---|---|---|
| Flexion | 0–120° | Limited and painful = OA or hip flexion contracture |
| Extension | 0–20° | Test in prone or with Thomas test |
| Abduction | 0–45° | Reduced in OA |
| Adduction | 0–30° | |
| Internal rotation | 0–45° | Often first movement lost in OA |
| External rotation | 0–45° | Increased ER at rest = fracture of neck of femur |
💎 Clinical Pearl
Internal rotation is the first movement lost in hip osteoarthritis. If a patient has reduced and painful internal rotation with a normal X-ray, still suspect early OA. Testing internal rotation in flexion (flex hip and knee to 90°, rotate foot outward) is more sensitive.
Special Tests
Thomas Test — Fixed Flexion Deformity
🧠 Mnemonic
Thomas test — detect a hidden hip flexion contracture
Flatten the lumbar lordosis by maximally flexing the normal hip to the chest.
If the other hip lifts off the table, there is a fixed flexion deformity on that side.
The angle the thigh makes with the table = the degree of deformity.
- 1Patient lies supine
- 2Fully flex the unaffected hip and hold it — this flattens the lumbar lordosis
- 3Observe the affected leg: if it rises off the table, fixed flexion deformity is present
- 4Measure the angle of flexion
Trendelenburg Test — Abductor Strength
- 1Patient stands on the affected leg (one hand on the wall for balance)
- 2Ask them to lift the unaffected leg off the ground
- 3Observe the pelvis: positive = the pelvis on the unsupported side drops
- 4Indicates weakness of the ipsilateral hip abductors (gluteus medius and minimus)
Causes of positive Trendelenburg: OA, total hip replacement, hip fracture, superior gluteal nerve palsy, polio.
🧠 Mnemonic
"The sound side sags" — positive Trendelenburg
The pelvis drops on the side that is NOT weight-bearing.
The pathology is on the weight-bearing (standing) side.
FABER Test — Flexion, Abduction, External Rotation
Tests the hip joint and sacroiliac joint:
- 1Flex the hip, place ankle over the contralateral knee (figure-of-four position)
- 2Gently press the knee toward the table
- 3Positive: pain in the groin = hip joint pathology; pain in the posterior pelvis = sacroiliac joint pathology
Leg Length Measurement
- True leg length: anterior superior iliac spine (ASIS) to medial malleolus — measures structural discrepancy
- Apparent leg length: xiphisternum (or umbilicus) to medial malleolus — measures functional discrepancy from pelvic tilt
A difference of over 1 cm in true leg length is clinically significant.
To Complete
- Examine the lumbar spine (referred hip pain from L3/L4)
- Examine the knee (hip pathology commonly presents as knee pain)
- Neurovascular assessment: femoral, popliteal, and distal pulses; sensation in L2/L3/L4 distribution
- Investigations: weight-bearing AP pelvis and lateral hip X-ray; MRI for soft tissue pathology or occult fracture
Frequently Asked Questions
"What is the Trendelenburg sign and what causes it?"
A positive Trendelenburg sign is when the pelvis drops on the unsupported side during single-leg stance — the pelvis tilts away from the standing leg. This indicates weakness of the hip abductors (gluteus medius and minimus) on the weight-bearing side. Common causes include hip osteoarthritis, total hip replacement (abductor detachment or superior gluteal nerve injury), hip fracture, and polio.
"What does the Thomas test assess and how do I perform it?"
The Thomas test detects a fixed flexion deformity at the hip. With the patient supine, fully flex the unaffected hip to the chest — this eliminates the compensatory lumbar lordosis. If the affected hip rises off the table, a fixed flexion contracture is present; the angle it rises equals the degree of deformity. This is common in hip OA and can mask as apparent normal extension posture due to the lordosis.
"Why is internal rotation the first movement lost in hip OA?"
Internal rotation of the hip stretches the posterior capsule, which becomes the most inflamed and thickened structure in early hip osteoarthritis. Pain and restriction of internal rotation — particularly when tested in flexion — is often the earliest reproducible clinical finding of hip OA, even before X-ray changes are apparent.
"How do I measure true vs apparent leg length discrepancy?"
True leg length is measured from the anterior superior iliac spine to the medial malleolus — this measures actual bony length. Apparent leg length is measured from the umbilicus or xiphisternum to the medial malleolus — this includes pelvic tilt and positioning. A difference between the two suggests pelvic obliquity or an adduction/abduction deformity rather than a true bony length discrepancy.
"How does hip pathology present as knee pain?"
The hip and knee share the obturator nerve (L2–L3) and femoral nerve supply. Referred pain from hip OA, avascular necrosis, or a slipped upper femoral epiphysis (SUFE) classically presents as medial knee pain in children and anteromedial thigh or knee pain in adults. Examining the hip is mandatory in any patient with knee pain — move the hip through its range before attributing the pain to the knee.
Related guides: [Knee Examination OSCE](/blog/knee-examination-osce) · [Musculoskeletal History OSCE](/blog/musculoskeletal-history-osce) · [Falls Assessment OSCE](/blog/falls-assessment-osce)