Ferrante - Radiculopathies Flashcards
What is a muscle domain (myotome)?
What motor axons are in a nerve, and what they innervate
What is the key feature of radiculopathies?
- PAIN
- Often radiating: sharp, stabbing, hot, electric
- Often aggravated by maneuvers that stretch the root
What nerve root is most often involved in cervical radiculopathies?
- C7: triceps
- Sensory abnormality on third finger
- C6-C7 disc
- NOTE: no red star associated with this
What disc is most often involved in lumbosacral radiculopathies?
- S1: foot plantar flexion
- Achilles tendon (ankle jerk) reflex DEC
- Sensory abnormality on lateral foot, small toe, sole
- L5-S1 disc usually involved
- NOTE: no red star associated with this
What are the 2 MCC’s of radiculopathies?
- Disk herniation and degeneration:
1. Herniation nucleus pulposus (HNP): C7 >> C6 (these ppl usually <50)
2. Spondylosis: degenerative OA of joints bt center of spinal vertebrae or neural foramina that can result in N root compression (C5 and C6 more frequent; ppl >50) - 95% of lumbosacral radiculopathies (HNP’s) affecting L5 or S1
- NOTE: no red star
What is the best maneuver for cervical radiculopathies?
- Neck extension
- This and other maneuvers often aggravate pain by stretching the nerve root
How can radicular pain be relieved positionally?
- Radicular pain often relieved by maneuvers that open the neural foramina
- EX: walking uphill is less painful than downhill, and bike riding is less painful than walking
Why do spinal percussion?
- May identify disorders of the vertebral bodies, like metastatic disease, epidural abscess, or osteomyelitis
If pt presents with numbness in the pinky, what 2 neuropathies should you be concerned about? How can you determine which one is ailing the pt?
- Numbness in pinky = ulnar neuropathy or C8
1. Numbness for these 2 is similar, but weakness is different - If thinking C8, also want to know if C8 part of median is affected:
1. Flexor pollicis longus and extensor indicis (thumb and index finger) -> ask them to flex thumb and extend index finger
How does stocking-glove numbness present?
- In a length-dependent distribution: sensory symptoms precede motor, are > motor
- Axon disruption: Wallerian degeneration
- Numbness starts furthest from spinal cord (bilaterally), and travels up in a stocking distribution
1. At about calf level, fingers start to be affected too, i.e., depends on distance from spinal cord - Symmetric, generalized polyneuropathy
- Most are toxic-metabolic in etiology: #1 diabetes, #2 alcohol
In a spiral groove lesion, which mm supplied by the Radial N will be spared?
- Triceps mm: if triceps are affected, then the lesion MUST be above the spiral groove
What part of the hand will be spared in carpal tunnel syndrome?
- Thenar eminence area of hand
- NOTE: can’t be carpal tunnel syndrome if skin over thenar eminence affected
51-y/o man with weakness in L hand for 3 months. Everything looks normal on exam, except atrophy of first dorsal interosseous, and when asked to hold paper bt thumb and index finger, had to flex last phalanx of the thumb (Froment’s sign).
Also DEC pinprick sensation in left 5th digit, and half of 4th. Forearm sensation normal. Weakness if flexor carpi ulnaris. Where is the lesion?
- Ulnar N above the elbow
- You know it is Ulnar N bc split sensation on 4th digit (other half covered by C8 of Median N)
- You know it is above elbow bc flexor carpi ulnaris comes off before wrist (and back of hand also numb)
60-y/o man with back pain radiating to L leg. Exam revealed normal strength, but absent left ankle reflex, and positive straight leg raising test on the left.
What is the dx?
- S1 radiculopathy: ankle reflex goes with this root
How are most radiculopathies managed clinically?
- Conservatively: most improve within 6 weeks
1. Bed rest (0-2d), if required
2. Physical therapy
3. Medications: NSAIDs, Prednisone, benzos
4. Nerve block
