Dermatomes, Myotomes, & Reflexes Flashcards
What are the key sensory points of the upper body? Which spinal roots are involved in each? (C2-T2)
- C2: posterior 1/2 of head, upper neck
- C3: supraclavicular fossa lower neck
- C4: acriomio-clavicular joint upper chest
- C5: lateral side of antecubital fossa lateral 1/2 of upper arm
- C6: thumb lateral 1/2 of lower arm and hand, thumb and index
- C7: middle finger
- C8: little finger medial 1/2 of hand, ring and little
- T1: medial side of antecubital fossa medial 1/2 of lower arm
- T2: apex of axilla medial 1/2 of upper arm, upper chest
What are the key sensory points of the lower body? Which spinal roots are involved in each? (L1-S5)
- L1: midpoint between T12 and L2 upper thigh
- L2: mid anterior thigh anterior middle thigh
- L3: medial femoral condyle anterior lower thigh and upper leg
- L4: medial malleolus medial 1/2 of lower leg
- L5: base of 3rd toe lateral 1/2 of lower leg, dorsum of foot
- S1: lateral heel posterior mid-line of lower 1/2 of leg, heel, lateral foot
- S2: popliteal fossa posterior thigh and posterior upper 1/2 of leg
- S3: ischial tuberosity saddle area
- S4-S5: peri-anal region
Where are the key sensory points for spinal roots T4, T10, and T12?
- T4: nipple
- T10: umbilicus
- T12: midpoint of inguinal ligament
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in shoulder abduction? What about winging of the scapula?
- shoulder abduction: deltoid; C5; axillary
- winging of scapula: serratus anterior; C5, C6, C7; long thoracic nerve
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in elbow flexion? What about elbow extension?
- elbow flexion 1: biceps; C5, C6; musculocutaneous
- elbow flexion 2: brachioradialis; C6; radial
- elbow extension: triceps; C7; radial
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in wrist extension?
- wrist extension: extensor carpi radialis longus; C6; radial
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in finger extension? What about finger flexion?
- finger extension: extensor digitorum; C7; radial
- finger flexion: flexor digitorum; C8; median/ulnar
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in index abduction? What about thumb abduction?
- index abduction: 1st dorsal interosseus muscle; T1; ulnar
- thumb abduction: abductor pollicis brevis; T1; median
Which spinal roots are involved in the biceps jerk reflex? The triceps jerk? The supinator jerk? The finger jerk?
- biceps jerk: C5, C6
- triceps jerk: C7, C8
- supinator jerk: C5, C6
- finger jerk: C8
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in hip flexion? What about hip extension?
- hip flexion: iliopsoas; L1, L2; lumbosacral plexus
- hip extension: gluteus maximus; L5, S1; inferior gluteal
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in hip adduction? What about hip abduction?
- hip adduction: adductors; L3, L4; obturator
- hip abduction: gluteus minimus/medius; L4, L5: superior gluteal
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in knee extension? What about knee flexion?
- knee extension: quadriceps; L3, L4; femoral
- knee flexion: hamstrings; S1; sciatic
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in ankle dorsiflexion? What about ankle plantarflexion?
- ankle dorsiflexion: tibialis anterior; L4; deep peroneal
- ankle planarflexion: gastrocnemius; S1, S2; posterior tibial
Which muscle(s), nerve root(s), and peripheral nerve(s) are involved in tarsal inversion? What about tarsal eversion?
- tarsal inversion: tibialis posterior; L4, L5; tibial/sciatic
- tarsal eversion: peroneus longus/brevis; L5, S1; superficial peroneal
Which spinal roots are involved in the knee jerk reflex? The ankle jerk? The Babinski reflex?
- knee jerk: L3, L4
- Achilles/ankle jerk: S1, S2
- Babinski: L5, S1, S2
