颅神经
颅神经直接从脑或脑干中出现，而脊神经直接从脊髓中出现。下面列出了颅神经，并且更详细地介绍了提供本书中讨论的特定骨骼肌的颅神经。
颅神经I，即嗅神经，负责携带与嗅觉有关的感觉信息。颅神经II是视神经，负责将视网膜的视觉信息传递给大脑。
颅神经III，动眼神经，控制眼睛的大部分运动（连同颅神经IV和VI）并支配上睑提肌。颅神经IV，即​​滑车神经，是支配单个肌肉的运动神经，即眼睛的上斜肌（本书未涉及）。
颅神经V，即三叉神经，是颅神经中最大的一种，有三个主要部分：眼（V1），上颌（V2），
 
和下颌骨（V3）。三叉神经负责感觉
面部和咀嚼和咀嚼等功能。眼科和上颌骨分割都是纯粹的感觉，而下颌骨分裂同时具有感觉和运动功能。下颌骨分支支配咬肌，颞肌，翼状胬肉，肌腱和二腹肌（前腹）。
颅神经VI，即外展神经，控制着一只肌肉的运动，即眼外直肌（本书未涉及）。
从中脑的脑桥，颅神经VII，面神经，通过内耳道进入颞骨，然后通过乳突孔进入，在那里分支到后耳分支。五个主要分支 - 颞，颧，颊，（边缘）下颌和颈椎（记住助记符“通过汽车到桑给巴尔”） - 如下所述支配面部肌肉。
Temporal branches: frontalis, temporoparietalis, auricularis anterior and superior, orbicularis oculi (also innervated by the zygomatic branches), procerus, and corrugator supercilii. Zygomatic branches: orbicularis oculi (also innervated by the temporal branches) and zygomaticus major (also innervated by the buccal branches). Buccal branches: depressor septi nasi, orbicularis oris (also innervated by the mandibular branches), levator labii superioris, levator anguli oris, nasalis, zygomaticus major (also innervated by the zygomatic branches), zygomaticus minor, depressor anguli oris, risorius, and buccinator. Mandibular branches: orbicularis oris (also innervated by the buccal branches), depressor labii inferioris, depressor anguli oris (also innervated by the buccal branches), mentalis, and stylohyoid. Cervical branches: platysma. Furthermore, the posterior auricular branch subdivides into the auricular branch, which innervates the auricularis posterior, and the occipital branch, which innervates the occipitalis. The digastric branch, which arises close to the stylomastoid foramen, innervates digastric.
Cranial nerve VIII, the vestibulocochlear nerve (also known as the auditory vestibular nerve), transmits sound and equilibrium (balance) information from the inner ear to the brain.
Cranial nerve IX, the glossopharyngeal nerve, originates from the medulla oblongata and exits the skull through the jugular foramen. Its main function is sensory.
Cranial nerve X, the vagus nerve, supplies motor parasympathetic fibers to all organs except the adrenal glands.
Cranial nerve XI, the accessory nerve, is unique in that it is formed by both cranial and spinal components that combine and then diverge, with the cranial portion joining the vagus nerve (X), and the spinal portion descending to innervate sternocleidomastoid and trapezius.
Cranial nerve XII, the hypoglossal nerve, innervates muscles of the tongue, although geniohyoid is innervated by the fibers of cervical nerve C1, conveyed by the hypoglossal nerve X11.
Cranial Nerves and Skull Passageways (External View)
Cranial Nerves and Skull Passageways (Internal View)
Cranial Nerve V—Trigeminal Nerve
Sensory Distribution
Motor Distribution
Cranial Nerve VII—Facial Nerve
Cranial Nerve XI—Accessory Nerve
Cervical Plexus
The cervical plexus is a network of nerves, formed by the ventral rami of the four upper cervical nerves (C1–4). The cervical plexus is located in the neck, deep to sternocleidomastoid, and has two types of branch: cutaneous and muscular. The muscular branch comprises: the ansa cervicalis nerve, which innervates sternohyoid, sternothyroid, thyrohyoid, and omohyoid; the phrenic nerve, which innervates the diaphragm; and segmental nerves, which innervate the middle and anterior scalenes. Furthermore, longus colli, longus capitis, rectus capitis lateralis, and rectus capitis anterior are also supplied via the cervical plexus. The medial brachial cutaneous nerve innervates the skin on the medial brachial side of the arm.
Brachial Plexus and Axillary Nerve
The brachial plexus is a network of nerves, formed by the anterior rami of the four lower cervical nerves (C5–8) and first thoracic nerve (T1). The brachial plexus is divided into roots (anterior rami of C5–8 and T1), trunks (superior, middle, inferior), divisions (each of the three trunks splitting in two, to create six divisions), cords (the six divisions regroup to form three cords—lateral, posterior, medial), and finally branches (nerves). Scalenus posterior, rhomboids, latissimus dorsi, supraspinatus, infraspinatus, subscapularis, teres major, and
levator scapulae are innervated by the brachial plexus. The five main nerves originating from the brachial plexus are the axillary, median, musculocutaneous, ulnar, and radial nerves.
Axillary Nerve
The axillary nerve carries nerve fibers from C5 and C6, innervating the deltoid and teres minor.
Musculocutaneous Nerve
The fibers of the musculocutaneous nerve are derived from C5–7. It innervates coracobrachialis, biceps brachii, and brachialis. The musculocutaneous nerve is implicated when the patient presents with weak flexion and supination of the forearm. Wearing a heavy bag over one shoulder or carrying a backpack can irritate the nerve.
Median Nerve
This nerve is derived from the anterior primary rami of C6, C7, C8, and T1. It gives off no branches in the arm but innervates all of the flexors in the forearm, except flexor carpi ulnaris and the medial half of flexor digitorum profundus (both supplied by the ulnar nerve). These forearm muscles are pronator teres, flexor carpi radialis, palmaris longus, flexor digitorum superficialis, flexor digitorum profundus (lateral half), flexor pollicis longus, and pronator quadratus. In the hand, the median nerve also innervates flexor pollicis brevis (superficial head), opponens pollicis, abductor pollicis brevis, and the first and second lumbricals.
The median nerve supplies sensation to the lateral palm, palmar skin, and the dorsal nail beds of the lateral three and a half digits. Compression of this nerve in the wrist, as it passes through the carpal tunnel, can cause carpal tunnel syndrome.
Ulnar Nerve
The nerve fibers of the ulnar nerve derive from C8 and T1. The nerve passes down through the arm and then winds under the medial epicondyle to enter the forearm and supply flexor carpi ulnaris and half of flexor digitorum profundus (the other half being supplied by the median nerve). In the lower forearm, the dorsal and palmar cutaneous branches are given off. The ulnar nerve then passes superficial to the flexor retinaculum after which it divides into terminal branches. The superficial branch ends as digital nerves supplying the skin of the little finger and the medial half of the ring finger. The deep branch supplies the hypothenar muscles, two lumbricals, the interossei and the adductor pollicis.
The ulnar nerve is the longest unprotected nerve in the human body and is therefore prone to injury. This tends to occur at the elbow (e.g. fracture of the medial epicondyle) or at the wrist from a laceration.
Radial Nerve
The fibers of the radial nerve are derived from C5–T1; the nerve subdivides into muscular and deep branches. The muscular branch innervates triceps brachii, anconeus, brachioradialis, and extensor carpi radialis longus. The deep branch innervates extensor carpi radialis brevis and supinator. The posterior interosseous nerve (a continuation of the deep branch) innervates extensor digitorum, extensor digiti minimi, extensor carpi ulnaris, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, and extensor indicis.
The radial nerve sits in the spiral groove of the humerus and therefore a humeral shaft fracture may result in this nerve being damaged, leading to wrist-drop and loss of sensation of the skin over the anatomical snuffbox.
Lumbar Plexus
The lumbar plexus forms part of the lumbosacral plexus, and is formed by the divisions of the first four lumbar nerves (L1–4) and the subcostal nerve (T12). Branches include: the ilioinguinal and iliohypogastric nerves, which innervate internal oblique and transversus abdominis; the genitofemoral nerve, which innervates cremaster; the inferior gluteal nerve, which innervates gluteus maximus; and the superior gluteal nerve, which innervates tensor fasciae latae, gluteus medius, and gluteus minimus, Also supplied via the lumbosacral plexus are piriformis (nerve to piriformis L5, S1), obturator internus (nerve to obturator L5, S1, 2), gemellus superior and inferior (nerve to obturator L5, S1, 2), and quadratus femoris (nerve to quadratus femoris L4–5). See also the obturator, femoral, sciatic, tibial, and common fibular nerves discussed below.
Sacral Plexus
The sacral plexus is a branching network of nerves that provides motor and sensory nerves to part of the pelvis, posterior thigh, most of the lower leg, and the entire foot. The sacral plexus is itself derived from the anterior rami of spinal nerves L4, L5, S1, S2, S3, and S4. Each of these anterior rami gives rise to anterior and posterior branches. The anterior branches supply flexor muscles of the lower limb, and posterior branches supply the extensor and abductor muscles.
Obturator Nerve
The obturator nerve originates from the ventral divisions of the second, third, and fourth lumbar nerves in the lumbar plexus and innervates obturator externus, adductor brevis, adductor magnus, adductor longus, gracilis, and pectineus (occasionally). Despite its name, the obturator nerve is not responsible for the innervation of obturator internus, which is supplied by the nerve to obturator internus from the sciatic nerve.
Anterior view
Femoral Nerve
The femoral nerve, the largest branch of the lumbosacral plexus, is located in the thigh and not in the leg as some texts claim. It originates from the dorsal divisions of the ventral rami of the second, third, and fourth lumbar nerves (L2–4). In the femoral region, the nerve subdivides into the anterior and posterior divisions, before subdividing further into many smaller branches throughout the anterior and medial thigh. The anterior division innervates iliacus, sartorius, and pectineus, while the posterior division innervates rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.
Anterior view
Sciatic Nerve
The sciatic nerve is the longest and widest nerve in the human body. It is formed in the upper sacral plexus from the anterior primary rami of L4, L5, S1, S2, and S3. It passes out of the greater sciatic foramen, passing below piriformis. The sciatic nerve innervates biceps femoris, semimembranosus, and semitendinosus. True sciatic nerve damage can result in altered sensation, numbness, weakness, and pain. Depending on the source and level of irritation, the pain can be mild to severe. Sciatic nerve irritation usually occurs at the L5 or S1 level of the spine and only on one side. Pain can travel all the way to the foot and can affect normal motion, but with normal healing, the referred pain should dissipate and become more central. Unresolved chronic pain, especially of unknown origin, should be brought to the attention of the doctor or primary healthcare team.
Posterior view
At approximately mid thigh, the sciatic nerve divides into the tibial nerve and the common fibular nerve.
Tibial Nerve
The tibial nerve is a branch of the sciatic nerve, and innervates the muscles of the posterior compartment of the leg, including gastrocnemius, plantaris, soleus, flexor digitorum longus, tibialis posterior, popliteus, and flexor hallucis longus. One of its branches, the medial plantar nerve, innervates abductor hallucis, flexor digitorum brevis, flexor hallucis brevis, and the first lumbrical. The other branch, the lateral plantar nerve, innervates abductor digiti minimi, quadratus plantae, adductor hallucis, flexor digiti minimi brevis, plantar interossei, dorsal interossei, and the three lateral lumbricals.
Common Fibular Nerve
The common fibular nerve originates, via the sciatic nerve, from the dorsal branches of the fourth and fifth lumbar nerves (L4–5) and the first and second sacral nerves (S1–2). It divides into the superficial fibular nerve and the deep fibular nerve. The superficial fibular nerve innervates fibularis longus and fibularis brevis. The deep fibular nerve innervates tibialis anterior, extensor digitorum longus, fibularis tertius, extensor hallucis longus, extensor hallucis brevis, and extensor digitorum brevis.
Anterolateral view, right leg
参考：The Pocket Atlas of Human Anatomy A Reference for Students of Physical Therapy, Medicine, Sports, and Bodywork Student Edition |
