Neurological System (Lower Limb) Flashcards
When examining the power of the lower limb, what movement is assessed?
Hip flexion and extension
Knee flexion and extension Ankle dorsiflexion and plantarflexion
What are the two reflexes examined in the lower limb?
Patellar
Achilles
Which nerve roots are assessed in the patellar reflex?
L2-L4
Which nerve roots are assessed in the achilles reflex?
S1-S2
What are the three examinations performed to assess tone in the lower limb?
1) Leg roll
2) Leg lift
3) Ankle clonus
How is leg lift performed?
Quickly lift the leg off the bed at the knee joint, heel should remain in contact with the bed.
How is ankle clonus performed?
Quickly dorsiflex and partially evert the foot, clonus is felt but more than 5 is abnormal
Which muscles are concerned with hip flexion?
Psoas major Iliacus Sartorius Rectus femoris pectineus
Which nerve is associated with hip flexion?
Femoral nerve
Which nerve is associated with hip extension?
Inferior gluteal nerve
Which muscle is concerned with hip extension?
Gluteus maximus
Which muscles are associated with hip abduction?
Gluteus medius
Gluteus minimus
Which nerve is associated with hip abduction?
Superior gluteal nerve
Which nerve is associated with hip adduction?
Obturator nerve
Which muscles are associated with hip adduction?
Adductor longus
Adductor brevis
Adductor Magnus
Which muscle is associated with internal rotation of the hip?
Obturator externus (all adductors, semitendinosus, semimembranosus)
Which muscles are associated with external rotation of the hip?
Piriformis, obturator internus, gemellus superior and inferior, quadratus femoris
Which muscles are associated with knee flexion?
Biceps femoris, semtindonosus, semimembranosus and gracillis
Which muscle is associated with extension of the knee joint?
Quadriceps femoris
How is the Trendelenburg test performed?
- With consent, position your hands on the patient’s iliac crests.
- Ask the patient to lift each foot in turn off the floor
- When the right foot is raised, the left hip abductors are being tested
- When the left foot is raised, the right hip abductors are being tested.
- The abductors should be strong enough to support the pelvis and keep it level on a one-legged stance. They may even contract sufficiently that you feel slight upwards tilt in the pelvis.
- If there is weakness in the abductors, they will be unable to stabilise the hip on the weight bearing femur, so the pelvis will sag towards the unsupported side.
When the left leg is raised which muscle group is being assessed in the Trendelenburg test?
Right hip abductors
If there is a weakness in the left hip abductors, how will this be shown?
Unable to stabilise the hip on the weight bearing femur, thus the pelvis will sag towards the unsupported side, the right
How is knee extension assessed?
Quadriceps
Bend the knee and ask the patient to straighten the knee whilst applying resistance
When assessing the power of knee extension, which muscle group is being examined?
Quadriceps
When assessing the power of knee flexion, which muscle group is being examined?
Hamstrings
How is knee flexion assessed?
Instruct the patient to begin flexing the knee towards them against resistance
Which nerve is associated with knee flexion?
Sciatic nerve
How is dorsiflexion assessed?
Resist by pushing foot downwards
Which muscles are concerned with dorsiflexon?
Tibialis anterior, extensor hallucis longus
Extensor digitorum longus
Which nerve is concerned with the anterior compartment of the leg, and dorsiflexion?
Deep fibular nerve
How is plantarflexion assessed?
Resist by pushing the foot upwards and inform the patient to point their foot downwards to oppose this motion
Which nerve is involved with platarflexion?
Tibial nerve (s1-s2)
How is inversion assessed?
Place hand laterally and instruct the patient to push against applied resistance
How is eversion assessed?
Place hand medially and instruct the patient to push against applied resistance
At which joint does inversion occur?
Subtalar joint
Which nerve roots are concerned with the knee jerk reflex?
L3-L4
How can the knee jerk reflex be examined?
- Ensure that the patient’s legs are hanging freely over the side of the bed and is completely relaxed.
- Instruct patient to do the Jendrassik manoeuvre (Clenching the teeth and flexing both sets of fingers in a hook-like form).
- Tap the patellar tendon with the tendon hammer.
Which nerve root is associated with the ankle-jerk reflex?
S1-S2
How is the ankle-jerk reflex examined?
- Support the leg such that their hip is slightly abducted, the knee Is flexed and the ankle is dorsiflexed.
- Tap the Achilles tendon.
A femoral nerve lesion is associated with what?
Quadriceps paralysis- weakness of knee
Difficulty climbing up or down the stairs
What sensory losses are associated with a femoral nerve lesion?
Anterior and medial thigh, medial side of leg and medial border of foot
Which cutaneous branch of the femoral nerve is affected in a femoral nerve lesion?
Saphenous nerve
Which muscle group is affected by an obturator nerve lesion?
Paralysis of the adductors
What are the sensory losses are associated with an obturator nerve lesion?
Medial cutaneous nerve of the thigh
Paralysis of the adductor group of muscles is concerned with which nerve lesion?
Obturator nerve
What motor function losses are concerned with a common fibular nerve lesion?
Foot drop
Foot extensors and evertors are paralysed
Which muscles are affected in a common fibular nerve lesion?
EDL, EHL and tibialis anterior (anterior group)
Peroneal muscles (Lateral)
What sensory losses are associated with common fibular nerve lesion?
Loss in anterior and lateral side of leg and dorsum of foot
Which muscles are affected in a tibial nerve lesion?
Hamstrings and all posterior muscles of the leg and foot
What motor deficits occur due to a tibial nerve lesion?
Foot remains in the dorsiflexed and everted position
An injury to the sciatic nerve will manifest as what motor function?
Hamstrings and all muscles below the knee are paralysed
Knee flexion is affected.
What is sciatica?
Pain radiating from the posterior back into the buttock, posterior/lateral thigh and into leg.
• Caused by herniated lumbar intervertebral disc which compresses on the L5-S1 component of the sciatic nerve.
What are the nerve roots of the sciatic nerve?
L5-S1
What are the borders of the femoral triangle?
1) Inguinal ligament (Superior)
2) Adductor longus (Medial)
3) Sartorius (Lateral)
Which dermatome is associated with the area of the inguinal ligament?
L1
The L1 dermatome is associated with which area?
Area of the inguinal ligament
Which dermatome is associated with the lateral side of the thigh?
L2
Which dermatome is associated with the lower medial side of the thigh?
L3
The L2 dermatome is associated with what aspect of the thigh?
Lateral side of the thigh
The L3 dermatome is associated with what aspect of the thigh?
The lower medial side of the thigh (knee)
Which dermatome is associated with the great toe, and the medial side of the leg?
L4
L4 is associated with which toe?
The great toe
L5 is associated with which side of the leg and foot?
Lateral side of the leg, and middle three toes
Which dermatome is associated with the lateral side of the leg?
L5
The S1 dermatome is associated with which toe?
Little toe
The little toe is associated with which dermatome?
S1
The S2 dermatome is associated with which aspect of the lower limb?
Back of upper leg and whole thigh
Popliteal fossa
Swelling of the popliteal fossa is associated with what pathology?
Baker cyst
Which dermatome is associated with the gluteal fold?
S3
How does compartment syndrome occur?
Blockage of venous drainage increasing the pressure within the muscle compartment of the leg- this can cause muscle ischaemia and tissue death
What are the causes of compartment syndrome?
Fractures, burns, infections or prolonged limb compression
What are the 6ps associated with compartment syndrome?
Pain Pallor Pulselessness Perishingly cold Paraesthesia Paralysis
What are the examinations linked with compartment syndrome?
Swollen limb and passive movement is painful
What is the treatment for compartment syndrome?
Relieve pressure by removing any dressings, casts and splints
Open fasciotomy
A woman who, after an accident, presented with newly acquired gait problems was asked to raise her right leg when standing, and it was noted that her pelvis dropped on the right side. Which nerve did the doctors believe was likely to be damaged?
left superior gluteal nerve
A man presented with a penetrating injury on the postero-medial aspect of the right knee which resulted in loss of cutaneous sensation of the anteromedial aspect of the right leg and medial border of the right foot. Which cutaneous nerve is most likely affected in this injury?
Saphenous nerve
The posterior tibial arterial pulse can be felt posterior and inferior to the medial malleolus. Which tendon lies just posterior to the posterior tibial artery at this location?
Flexor hallucis longus tendon
Where does the long saphenous vein cross the ankle from the foot to enter the leg?
Anterior to the medial malleolus
Which dermatome is used to assess the medial aspect of the leg?
L4
Which nerve root is tested in the supinator reflex?
C6
Which joint do you check for clonus?
Ankle
Which nerve is responsible for finger extension?
Radial nerve
A hypodense region on an axial brain CT indicates what type of stroke?
ischaemic stroke
How is a haemorrhagic stroke indicated on an axial CT?
Bright spots - indicating blood