N3 Anatomy and Physiology (1st Sem AY 2022-2023)

Turning a knob

1. Supinator

   1. Action: supinate the forearm

   2. Innervation: Posterior interosseous nerve

2. Pronator teres

   1. Action: Pronation of forearm at the proximal radioulnar joint, flexion of the forearm at the elbow joint

   2. Innervation: median nerve

3. Pronator quadratus

   1. Action: produces forearm pronation by acting on the proximal radioulnar joint

   2. Innervation: interosseous nerve of forearm

Throwing a baseball overhead (if right handed)

1. Left erector spinae

   1. Action: straighten the back and provide for side-to-side rotation

   2. Innervation: The erector spinae muscles are innervated by the dorsal rami of the first cervical nerve (C1) through the fifth lumbar nerve (L5).

2. Left gluteus maximus

   1. Action: extension, external rotation, abduction and adduction of the thigh

   2. Innervation: inferior gluteal nerve

3. Teres major

   1. Action: produce the movements of the humerus at the glenohumeral joint

   2. Innervation: supplied by the lower subscapular nerve (C5-C7) a branch of the brachial plexus

Kicking a ball

1. Psoas major

   1. Action: flexion and lateral rotation of the thigh at the hip

   2. Innervation: anterior rami of the lumbar spinal nerves, mainly L1 and L2, with some contributions from L3 and L4

2. Psoas minor

   1. Action: it acts on the lumbar spine to produce a weak flexion of the trunk

   2. Innervation: Anterior ramus of spinal nerve L1

3. Quadriceps

   1. Action: extend or straighten the knee

   2. Innervation: Femoral nerve

Doing sit-ups

1. Obliques

   1. Action: flex the trunk

   2. Innervation: anterior rami of the thoracic spinal nerves T7-T12

2. Rectus abdominis

   1. Action: move the body between the ribcage and the pelvis

   2. Innervation: thoracoabdominal nerves

3. Transverse abdominis

   1. Action: stabilise the trunk and maintain internal abdominal pressure

   2. Innervation: mainly supplied by the terminal branches of the lower five intercostal nerves and the subcostal nerve

Walking

1. Quadriceps

   1. Action: extend or straighten the knee

   2. Innervation: Femoral nerve

2. Anterior tibialis

   1. Action: dorsiflexor of the foot

   2. Innervation: deep fibular nerve

3. Peroneals 

   1. Action: plantar flex and evert the foot

   2. Innervation: superficial fibular nerve

Breathing

1. Diaphragm

   1. Action: Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges. Upon exhalation, the diaphragm relaxes and returns to its shape, and air is forced out of the lungs.

   2. Innervation: phrenic nerve

2. External intercostal

   1. Action: The external intercostal muscles elevate the ribs during forced inhalation and are functionally classified as the accessory respiratory musculature

   2. Innervation: anterior rami of spinal nerves

3. Parasternals

   1. Action: active during each inspiratory breath and function to expand the chest wall and the lungs

   2. Innervation: intercostal nerves