Lower limbs Pathology and Clinical Skills

Question 1

what is compartment syndrome?

Answer 1

This is a clinical syndrome where the pressure in the muscle compartment is so high that the venous drainage becomes blocked.

Pressure is very high that it can cause muscle ischaemia and death.

Question 2

what are the causes of compartment syndrome

Answer 2

Infections

Fractures

Burns

Prolonge lower limb compression

Question 3

what are the presentations of compartment syndrome

Answer 3

it commonly presents with pain, muscle tenderness and swelling. In later stages it presents with the 6 Ps:

• Pallor
• Pulselessness
• Paralysis
• Perishingly cold
• Pain
• Paresthesia

Question 4

What would you find on examination for a pt with compartment syndrome

What other investigation can you do?

Answer 4

On examination:

• The limb is swollen
• Very painful on passive movement

Diagnosis is usually based on clinical suspicion however there are some devices which can measure intracompartmental pressure.

Question 5

what are the treatment options for compartment syndrome

Answer 5

Treatment is with relieving pressure, all dressings, casts, splints should be removed.

Open fasciotomy - this is a surgical procedure where the skin and deep fascia are opened along the length of a muscle compartment to relieve the pressure

Question 6

How many adjacent dermatomes are affected for a significant sensory loss to be detected? Why?

Answer 6

Atleast 3

This is because there is signifcant overlapping between between dermatomes

Question 7

what spinal nerve dermatomes do not have overlap? what are they called?

Answer 7

Autonomous sensory zones.

e. g. L3, L4, L5 and S1
- useful clinically as pain and abnormal sensation can be attributed to a single spinal root

Question 8

What sensory modalities can be tested?

Answer 8

• Light touch, localization of touch,
• Two point tactile discrimination,
• Pain, pressure, temperature, vibration,
• Sterognosis (3D)
• Passive joint movement,
• Postural sensibility.

Question 9

There’s is a line where there’s no overlap of dermatomes. what line is this?

This IS NOT AUTONOMOUS SENSORY zones

Answer 9

Across the axial line

Question 10

How do you test dermatomes of the lower limb

Answer 10

Same procedure as the hand but you have to put the specific point on the diagram

Question 11

what tendon reflexes of the lower limb should you test and what spinal roots are responsible for them

Answer 11

Patella tendon (knee jerk): L2, L3, L4 via Femoral nerve

Achilles tendon (ankle jerk) reflex ( S1 and S2) via the tibia nerve

Question 12

How can knee jerk myotactic reflex be facilitated

Answer 12

Jendrassik manoeuvre

Pt needs to voluntarily dorsiflex the same foot strongly whilst it is performed.

Question 13

how do you preform/elicit the ankle jerk reflex

Answer 13

pt sit over edge of bed with knee 90 degree

Locate the achilles tendon and strike it with hammer

The foot should plantar flex

Contraction of gastroceniomus should be seen

Question 14

what are the effects of Femoral nerve injury?

Answer 14

Motor:

• Quadriceps paralysis
• Weakness of knee
• Difficulty climbing up and down the stairs.
• Knee jerk reflex gone?

Sensory loss to:

• Anterior and medial thigh
• Medial side of the leg
• Medial border of the foot

Question 15

What are the effects of Obturator nerve injury

Answer 15

Motor:

• Paralysis of all adductor muscles except hamstring part of adductor magnus and pectineus.
• Cross legging affected

Sensory loss:

• Insignificant loss to the medial side of the thigh.
• Pelvic disease, ovarian tumours may cause pain on the medial thigh

Question 16

what are the effects of injury to the common fibular nerve

Answer 16

Motor:

• Foot extensor and evertors paralysed
• Foot drop seen (plantar flexed and inverted)

Sensory- loss to:

• Anterior and lateral side of the leg
• Dorsum of the foot

Question 17

what are the effects of Tibial nerve injury

Answer 17

Motor:

• Paralysis of hamstrong and all muscles of posterior leg and sole of the foot
• On inspection, foot is dorsiflexed and in everted postion.

Sensory loss on sole of foot

Question 18

What are the causes of sciatic nerve injury?

what are the effects of whole sciatic nerve injury.

Answer 18

CAUSES: pelvic fracture, hip joint dislocation/surgery, penetrating injuries.

Effects:

• Hamstrings and all muscles below knee are paralysed.
• Knee flexion affected
• Foot in plantar flexed position due to it’s wieght

Sensory loss below the knee EXCEPT a narrow areas on medial leg and foot (NOT BIG TOE) as this side is innervated by the saphenous nerve

Question 19

what is sciatica and what are the causes?

what can it be mistaken for?

Answer 19

Cause: Herniated lumbar intervertebral disc (L4/L5) or (L5/S1) which compresses the L5-S1 part of the sciatic nerve.

Pelvic gridle pain in pregancy can be misdiagnosed as sciatica

Question 20

where can you palpate the arteries of the lower limb

Answer 20

Femoral artery at mid inguinal point.

Popliteal artery: knee can be semi flexed or extended. Rest thumbs on tibai tuberosity and press with both hands to feel the artery just against the psoteirior surface of the tibia.

Posterior tibial artery: Between the medial Malleolus and Achilles

Dorsal pedalis: Mid dorsum of foot, lateral to the tendon of flexor hallucis longus

Question 21

what are you investigating when palpating arteries

Answer 21

Pulse

Rhythm

Character and volume

Radial-femoral delay

Symmetry

Question 22

what are the surgical/clincial usefulness of superficial veins of the lower limb

Answer 22

They can be harvested and used as vascular grafts especially for CABG

When they are readily visible they can be used for venous infusions

Question 23

What is intermittent claudication?

Answer 23

This is a pain in the legs secondary to chronic arterial insufficiency, which is caused by peripheral arterial disease (PAD).

Its main feature is pain, which develops after movement, which disappears on rest.

The area of pain is dependant on the arteries that are diseased.

Question 24

what is the claudication distance?

Answer 24

The claudication distance is the distance the patient can walk before they feel pain

Question 25

what would you fins on examination for a patient with intermittent claudication?

Answer 25

Leg is cold and pale, with a loss of hair and muscle mass.

A thorough examination of the feet is also required to see if there are any ulcers.

Weak or absent pulses.

Question 26

What are the consequences of the worsening PAD? and explain why

Answer 26

Night pain,- due to the loss of gravity and the reduction in cardiac output when sleeping.

Worsening PAD can also cause:

• Rest pain
• Tissue ulceration
• Gangrene,

PAD is so bad that the blood flow is not able to support the tissues.

Question 27

what is the treatment for PAD?

Answer 27

Treatment depends on the severity of the disease.

Milder forms of the disease are treated with symptom control and antiplatelets,

If there is rest pain or non-healing ulcers, patients are assessed for revascularization.