Introduction
Back pain is one of the most common presentations in medicine. The spine OSCE tests systematic physical assessment combined with clinical reasoning. Most mark schemes follow the Look-Feel-Move-Special Tests framework, finishing with a focused neurological screen.
💎 Clinical Pearl
Always ask about pain before touching. Start with the patient standing, then move to the couch. Announce every step.
Preparation
- Introduce yourself, confirm patient identity
- Explain the examination and gain verbal consent
- Adequate exposure: shirt off, back fully visible
- Ask patient to stand initially
1. Look (Inspection)
Inspect from behind, the side, and the front:
| What to look for | Clinical significance |
|---|---|
| Scoliosis | Idiopathic, neuromuscular, structural |
| Kyphosis | Osteoporosis, Scheuermann's disease, ankylosing spondylitis |
| Loss of lumbar lordosis | Muscle spasm, ankylosing spondylitis |
| Pelvic tilt or leg length discrepancy | Structural vs functional scoliosis |
| Antalgic posture or gait | Pain on weight-bearing |
| Skin: tuft of hair, sacral dimple | Spina bifida occulta |
2. Feel (Palpation)
Palpate systematically from the cervical spine downward:
- Spinous processes — midline tenderness, step deformity (spondylolisthesis)
- Paraspinal muscles — bilateral spasm or tenderness
- Sacroiliac joints — direct pressure pain (sacroiliitis in ankylosing spondylitis)
- Greater sciatic notch — pain radiating to the buttock and thigh
⚠️ Red Flag
Vertebral point tenderness worse at night, combined with systemic symptoms, raises concern for malignancy or discitis.
3. Move (Active Range of Motion)
| Movement | Normal range | Restricted in |
|---|---|---|
| Lumbar flexion | Touch toes | Disc prolapse, AS, OA |
| Extension | 25-30 degrees | Facet joint OA, spinal stenosis |
| Lateral flexion | 25 degrees each side | Structural scoliosis, muscle spasm |
| Rotation | 35 degrees each side | Facet joint disease |
Schober's Test
🧠 Mnemonic
Schober = 10 becomes 15
Mark a point at S1 (sacral dimple), then 10 cm above and 5 cm below. Ask the patient to flex maximally. The distance should increase by at least 5 cm (reaching 15+ cm). Less than 5 cm increase = restricted lumbar flexion. Classic in ankylosing spondylitis.
4. Special Tests (Patient on Couch)
Straight Leg Raise (SLR)
Raise the extended leg passively. Positive if it reproduces radicular pain below the knee at under 60 degrees. Indicates L4/L5 or L5/S1 nerve root compression.
Femoral Stretch Test
Flex the knee with the patient prone. Anterior thigh pain = L2/L3/L4 nerve root involvement.
Lower Limb Neurology Screen
| Level | Myotome | Reflex | Dermatome |
|---|---|---|---|
| L3/L4 | Knee extension | Knee jerk | Anterior thigh and medial leg |
| L4/L5 | Foot dorsiflexion | None reliable | Dorsum of foot and big toe |
| L5/S1 | Plantarflexion | Ankle jerk | Sole and lateral foot |
Red Flags — TUNAFISH
⚠️ Red Flag
Trauma
Unexplained weight loss
Neurological deficit — bladder or bowel
Age over 50 with new-onset back pain
Fever
Intravenous drug use
Steroid use or immunosuppression
History of malignancy
Any red flag warrants urgent MRI spine. Cauda equina symptoms require same-day emergency referral.
Cauda Equina Screening
Always ask: urinary retention, urinary or faecal incontinence, saddle anaesthesia (perianal and inner thigh numbness), bilateral leg weakness.
Common OSCE Diagnoses
| Diagnosis | Key features |
|---|---|
| Lumbar disc prolapse | SLR positive, dermatomal loss, reduced ankle jerk (L5/S1) |
| Ankylosing spondylitis | Young man, bilateral SI joint pain, restricted Schober's |
| Spinal stenosis | Bilateral claudicant leg pain, relieved by leaning forward (shopping trolley sign) |
| Vertebral fracture | Localised bony tenderness, elderly, steroids |
| Malignancy or discitis | Night pain, fever, systemically unwell, point tenderness |
How to Present
"On examination there was loss of lumbar lordosis. Schober's test showed an increase of only 3 cm, indicating restricted lumbar flexion. Straight leg raise was positive at 40 degrees on the right, reproducing right-sided radicular pain to the ankle. Ankle jerk was reduced on the right. Saddle sensation and bladder function were intact. My findings are consistent with right L5/S1 nerve root compression, likely secondary to disc prolapse."
"What are the red flags for back pain?"
TUNAFISH: Trauma, Unexplained weight loss, Neurological deficit (bladder or bowel), Age over 50 with new pain, Fever, IV drug use, Immunosuppression or steroids, History of malignancy. Any of these warrants urgent MRI spine.
"How do you perform Schober's test?"
Mark a point at S1 (sacral dimple level), then 10 cm above and 5 cm below. Ask the patient to flex forward as far as possible. Measure the new distance: it should increase by at least 5 cm. An increase of less than 5 cm indicates restricted lumbar flexion and is a classic finding in ankylosing spondylitis.
"What is cauda equina syndrome and why does it matter?"
Cauda equina syndrome is compression of the cauda equina nerve roots in the lumbar spinal canal. It presents with bilateral leg weakness, saddle anaesthesia (perianal and inner thigh numbness), and loss of bladder or bowel control. It is a neurosurgical emergency requiring same-day MRI and urgent decompression.
"How do you differentiate L4/L5 from L5/S1 disc prolapse clinically?"
L4/L5: weakness of foot and great toe dorsiflexion, sensory loss on the dorsum of the foot, normal ankle jerk. L5/S1: weakness of plantarflexion and foot eversion, sensory loss on the lateral foot and sole, reduced or absent ankle jerk.
Related guides: [Knee Examination OSCE](/blog/knee-examination-osce) | [Hip Examination OSCE](/blog/hip-examination-osce) | [Shoulder Examination OSCE](/blog/shoulder-examination-osce) | [Musculoskeletal History OSCE](/blog/musculoskeletal-history-osce)