Neuro - Lower limb

Question 1

Weakness of hip flexion, wasting of quadriceps, decreased knee jerk?
-sensory loss over thigh
(Intact hip adduction)

Answer 1

Femoral n. lesion (ex. diabetic amyoptophy)

-obturator n. (hip adduction) preserved

Question 2

Weakness of hip flexion/adduction, wasted quadriceps, decreased knee jerk?

Answer 2

L2/3/4 root or plexus lesion

Causes - malignancy, obstetric injury, diabetic amyotrophy

Question 3

UMN weakness in 1 leg - mainly hip/knee flexion and ankle dorsiflexion/eversion?

Answer 3

Corticospinal lesion

Test UL/face

Question 4

UMN weakness in bilateral legs?

Answer 4

Cord lesion (paraparesis) - look for sensory level

Question 5

Proximal weakness of UL+LL

-Ddx depends on reflexes

Answer 5

Normal reflexes - myopathy or NMJ pathology
Hyporeflexic - spinal muscular atrophy (SMN1 gene) or Lambert-eaton
Hyperreflexic - MND, multilacunar strokes, cervical myelopathy (arms may be hyporeflexic)

Question 6

Weakness in hip adduction?

Answer 6

Obturator n. lesion (obstetric injury)

Question 7

Distal leg weakness +/- hip extension, loss of ankle jerk?

Answer 7

Sciatic n. lesion

Question 8

Weakness of foot dorsiflexion/eversion/EHL?

b. Weakness of dorsiflexion only?

Answer 8

Common peroneal n. lesion (sensory loss lateral calf/foot)

b. Deep peroneal n. lesion (sensory loss between big and 2nd toe)

Question 9

Weakness of dorsiflexion/inversion/eversion?

Answer 9

L4/5 root or plexus lesion

Question 10

Distal LL weakness?

Answer 10

Ddx: 
peripheral neuropathy 
sciatic n. lesion (loss of ankle jerk)
root or plexus lesion
MND (anterior horn)

Question 11

UMN weakness in 1 leg - proceed?

Answer 11

Brown-sequard - check for pinprick/vibration loss inother leg
ACA occlusion - check primitive grasp reflex in ipsilateral hand
R leg - Lateral medullary syndrome - aphasia
UL+LL weakness same side - stroke

Question 12

Ix for peripheral neuropathy?

Answer 12

NCS - axonal vs demyelination
EMG - confirm denervation
Nerve biopsy
CSF - elevated protein in CIDP
Metabolic - BSL, B12, folate, vasculitic screen

Question 13

Pes cavus Ddx?

Answer 13

Charcot Marie Tooth
Friedrichs ataxia
Spina bifida

Question 14

Friedreichs ataxia?

Answer 14

Cerebellar
LMN weakness, pyramidal weakness (upgoing plantars), pes cavus
DCT - loss of vibration/proprioception
Cardiac - conduction defects, HOCM
Hearing loss
Diabetes

Question 15

Sensory ataxia causes

Answer 15

Sensory neuropathy
Tabes dorsalis
SCD
Subacute combined degeneration of the cord
MS