Physical Exam of the Lower Spine & Lower Extremity

Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

 

Physical Examination of the Lower Spine and Lower Extremity

Overview

The examination follows the usual orthopaedic sequence:

Inspection – Palpation – Range of motion – Muscle strength – Provocative/special tests -Thorough neurovascular examination

The neurological component should assess motor, sensory, reflexes, and upper motor neuron signs where relevant.

1. Inspection

Deformity and Alignment

Inspect for deformity in both:

• Coronal plane
  • Scoliosis
  • Pelvic obliquity
• Sagittal plane
  • Cervical lordosis
  • Thoracic kyphosis
  • Lumbar lordosis

Also inspect the patient from both front and back for asymmetry.

Skin and Soft Tissue

Look for:

• Café-au-lait spots
• Hairy patches
• Dimples
• Previous surgical scars
• Muscle wasting

specifically states that calf muscle atrophy may suggest L5–S1 weakness or neuropathy.

2. Palpation

Palpate the important bony landmarks:

• Iliac crests
• Posterior superior iliac spines
• Spinous processes
• Sacrum
• Greater trochanters
• Ischial tuberosities

Also palpate soft tissues for tenderness or trigger points involving:

• Paravertebral muscles
• Gluteal muscles
• Piriformis
• Sciatic notch
• Sacroiliac joints

also mentions attempting to palpate the sciatic nerve.

3. Gait Examination

Gait gives important clues to pathology.

Gait abnormality	Possible implication in transcript
Antalgic gait	Hip arthritis
Trendelenburg gait	Hip abductor weakness
Steppage gait	Foot drop / ankle dorsiflexor weakness
Wide-based staggering gait	Cervical myelopathy / neurological disorder

An important point is that cervical myelopathy can coexist with lumbar pathology, so gait disturbance should not automatically be attributed to the lumbar spine.

4. Pain With Spinal Movement

stresses asking:

Which movement causes pain, and which movement relieves it

Lumbar Spinal Stenosis

• Extension increases pain
• Flexion improves symptoms

Disc Pathology

• Flexion increases pain
• Sitting and leaning forward may increase disc-related pain according to

Therefore, presents these as opposite patterns:

Stenosis – worse with extension, better with flexion

Disc pathology – worse with flexion

5. Thoracolumbar Range of Motion

gives approximate values:

Movement	ROM stated
Flexion	~80°
Extension	~40°
Lateral bending	~40°
Rotation	~45°

For flexion, the distance from the fingertips to the floor may also be assessed.

notes that these values can vary.

6. Neurological Examination

Assess individual nerve roots from approximately:

L2 to S1

The examination includes:

• Sensory testing
• Motor testing
• Reflexes
• Provocative tests
• Upper motor neuron signs when indicated

7. Sensory Examination

describes testing four sensory modalities:

• Pain
• Light touch
• Temperature
• Proprioception

In routine practice,  says pain and light touch are most commonly tested.

The aim is to identify:

• A dermatomal pattern – suggests nerve-root pathology
• A glove/stocking type distribution – may suggest peripheral neuropathy

Dermatomal Distribution

Root	Sensory area
L2	Mid-anterior thigh
L3	Distal thigh / knee area
L4	Medial leg to medial foot
L5	Dorsum of leg/foot
S1	Lateral and plantar aspect of foot

8. Motor Examination

Hip Flexion

Main muscle:

Iliopsoas

Roots stated:

L1, L2, L3

Hip Adduction

Roots:

L2, L3, L4

Knee Extension

Roots:

L2, L3, L4

emphasizes L4 as an important contributor.

Ankle Dorsiflexion

Main muscle:

Tibialis anterior

Roots stated:

L4–L5

L5

Commonly tested by:

• Great toe extension
• Hip abduction via gluteus medius

S1

Commonly tested by:

Ankle plantar flexion

Main muscle group:

Gastrocnemius–soleus complex

High-Yield Motor Root Table

Root	Key motor test
L2	Hip flexion
L3	Knee extension
L4	Ankle dorsiflexion / knee extension
L5	Great toe extension / hip abduction
S1	Plantar flexion

9. Reflexes

mentions two main lower-extremity reflexes:

• Patellar reflex
• Achilles tendon reflex

These are used as part of the lower-limb neurological examination.

10. Provocative Tests

lists:

• Straight leg raise
• Contralateral straight leg raise
• Femoral stretch test
• Clonus
• Babinski

Straight Leg Raise

Used for:

L5–S1 nerve-root irritation

Contralateral SLR

associates this with:

Sequestered disc causing L5/S1 root irritation

Femoral Stretch Test

Used for:

L3–L4 nerve-root irritation

11. Upper Motor Neuron Signs

mentions:

• Clonus
• Babinski

These are used to look for an upper motor neuron lesion.

This is particularly relevant when cervical cord pathology may coexist with lumbar complaints.

12. Bulbocavernosus Reflex

discusses the bulbocavernosus reflex in relation to spinal shock.

The maneuver is described using rectal/urethral/genital stimulation, with a positive response consisting of:

Anal sphincter contraction

According to , return of this reflex indicates:

End of spinal shock

13. Sacroiliac Joint Examination

FABER Test

FABER is discussed as a useful SI-joint test, but  states:

It is not confirmatory.

Another useful historical/localizing feature is:

The patient pointing with one finger directly to the posterior SI joint as the site of pain.

considers this almost as useful as the FABER maneuver.

Diagnostic SI Injection

When SI-joint pain is suspected, suggests confirmation by:

Injection of local anesthetic into the SI joint followed by pain relief.

14. Waddell Signs

Waddell signs are described as:

Non-organic physical examination findings

Examples mentioned include:

• Non-anatomic/inconsistent weakness
• Superficial or non-anatomic tenderness
• Findings disproportionate to the rest of the examination

states that three or more positive signs may suggest that the complaints do not fit a purely anatomical pattern, but also emphasizes that:

Waddell signs are controversial.

They should therefore not be used simplistically to label a patient.

High-Yield Differential Pattern

Finding	Favors
Pain worse with lumbar extension	Lumbar stenosis
Pain better with flexion	Lumbar stenosis
Pain worse with flexion	Disc pathology
Antalgic gait	Hip pathology
Trendelenburg gait	Hip abductor weakness
Steppage gait	Foot drop
Wide-based gait	Myelopathy
SLR positive	L5/S1 root irritation
Femoral stretch positive	L3/L4 root irritation
Clonus/Babinski	UMN lesion
Finger pointing to SI joint	SI-joint source

Practical Examination Sequence

INSPECTION
Coronal deformity – sagittal alignment – pelvic obliquity -skin – scars -wasting

PALPATION
Iliac crest – PSIS – spinous processes – sacrum – greater trochanter – ischial tuberosity – soft tissues

GAIT
Antalgic – Trendelenburg – steppage- wide based

ROM
Flexion – extension – lateral bending – rotation

MOTOR
L2 – L3 – L4 – L5 – S1

SENSORY
L2 – L3 – L4 – L5 -S1

REFLEXES

PROVOCATIVE TESTS
SLR – crossed SLR – femoral stretch

UMN SIGNS
Clonus – Babinski

SI JOINT / NON-ORGANIC SIGNS
FABER – SI localization – Waddell signs

Key Take-Home Points

• Lower-spine examination should remain systematic and bilateral.
• Always inspect the entire spine in both coronal and sagittal planes.
• Gait can reveal hip, neurological, dorsiflexor, and cord pathology.
• Extension-provoked pain favors lumbar stenosis, whereas flexion-provoked pain favors disc pathology in ‘s framework.
• Sensory testing should look for a dermatomal distribution.
• Motor examination from L2 to S1 is essential.
• L5 – great toe extension and S1 – plantar flexion are particularly useful quick tests.
• SLR evaluates lower lumbar/sacral root irritation; femoral stretch evaluates higher lumbar roots.
• Do not forget clonus and Babinski when cord disease is possible.
• FABER may support SI-joint pathology, but  does not consider it confirmatory.
• Waddell signs are controversial and should be interpreted cautiously.

Exam Pearls

L2 – Hip flexion

L3 – Knee extension

L4 – Ankle dorsiflexion

L5 – Great toe extension

S1 – Plantar flexion

SLR – L5/S1

Femoral stretch – L3/L4

Stenosis – extension hurts, flexion relieves

Disc – flexion hurts

Clonus/Babinski – UMN lesion