Use this beside the OIA pages. Learn patterns first, then exceptions.
| Muscle | Primary innervation |
|---|---|
| Trapezius | Spinal accessory nerve (CN XI), with cervical contributions for proprioception |
| Levator scapulae | Dorsal scapular nerve + cervical nerves |
| Rhomboid major/minor | Dorsal scapular nerve |
| Serratus anterior | Long thoracic nerve |
| Pectoralis minor | Medial pectoral nerve |
| Deltoid | Axillary nerve |
| Supraspinatus / Infraspinatus | Suprascapular nerve |
| Teres minor | Axillary nerve |
| Subscapularis | Upper/lower subscapular nerves |
| Teres major | Lower subscapular nerve |
| Latissimus dorsi | Thoracodorsal nerve |
| Pectoralis major | Lateral and medial pectoral nerves |
| Biceps brachii | Musculocutaneous nerve |
| Brachialis | Primarily musculocutaneous nerve; small radial contribution may occur |
| Coracobrachialis | Musculocutaneous nerve |
| Triceps brachii / Anconeus | Radial nerve |
| Brachioradialis | Radial nerve |
| Pronator teres | Median nerve |
| Pronator quadratus | Anterior interosseous branch of median nerve |
| Supinator | Deep branch of radial nerve / posterior interosseous continuation |
| Most superficial forearm flexors | Median nerve, with flexor carpi ulnaris an important ulnar-nerve exception |
| Most forearm extensors | Radial nerve or its deep/posterior interosseous branches |
| SCM | Spinal accessory nerve (CN XI), cervical sensory/proprioceptive contributions |
| Scalenes | Anterior rami of cervical spinal nerves |
| Splenius capitis/cervicis | Posterior rami of cervical spinal nerves |
| Suboccipitals | Suboccipital nerve (posterior ramus C1) |
| Erector spinae / multifidi | Posterior rami of spinal nerves |
| Rectus abdominis / obliques / transversus | Thoracoabdominal nerves, with lower contributions varying by muscle |
| Diaphragm | Phrenic nerve (C3-C5) |
| Intercostals | Intercostal nerves |
| Iliacus | Femoral nerve |
| Psoas major | Anterior rami of lumbar spinal nerves |
| Gluteus maximus | Inferior gluteal nerve |
| Gluteus medius/minimus + TFL | Superior gluteal nerve |
| Piriformis | Nerve to piriformis |
| Obturator internus + superior gemellus | Nerve to obturator internus |
| Quadratus femoris + inferior gemellus | Nerve to quadratus femoris |
| Obturator externus | Obturator nerve |
| Quadriceps / Sartorius | Femoral nerve |
| Adductor longus/brevis/gracilis | Obturator nerve |
| Adductor magnus | Obturator division to adductor portion; tibial division of sciatic nerve to hamstring portion |
| Hamstrings | Primarily tibial division of sciatic nerve; short head biceps femoris is common fibular division |
| Gastrocnemius / Soleus / Plantaris / Popliteus / Tibialis posterior | Tibial nerve |
| Tibialis anterior / extensor compartment | Deep fibular nerve |
| Fibularis longus/brevis | Superficial fibular nerve |
| Fibularis tertius | Deep fibular nerve |
Anterior thigh = femoral. Medial thigh = obturator. Glute med/min/TFL = superior gluteal. Glute max = inferior gluteal. Posterior leg = tibial. Anterior leg = deep fibular. Lateral leg = superficial fibular. Most posterior forearm = radial. These patterns reduce memorization load.
Knowing a muscle's motor nerve does not mean the nerve lies directly under the muscle belly or should be pressed. Innervation knowledge helps explain weakness patterns and reinforces endangerment-site anatomy, but diagnosis of nerve lesions is outside entry-level massage scope.