Long thoracic nerve injury 1. The long thoracic nerve may be injured by a stab wound or in the course of removal of lymph nodes during a mastectomy. 2. Paralysis of the serratus anterior muscle occurs so that abduction of the arm past the horizontal position is compromised. In addition, the arm cannot be used to push with. 3. To test the function of the serratus anterior clinically, the patient is asked to face a wall and push against it with both arms. If the nerve is injured, the corresponding medial border and inferior angle of the scapula become prominent “ winging of the scapula”.
Distribution of Musculocutaneous Nerve
Median Nerve B
Median Nerve Median nerve injury at the elbow or axilla 1. The median nerve may be injured as a result of a supracondylar fracture of the humerus. 2. Paralysis of the muscles in the flexor compartment of the arm occurs so that flexion of the wrist is weakened, and the hand deviates to the ulnar side on flexion. In addition, flexion of the index and middle fingers at the distal and proximal interphalangeal joints is lost, and pronation is lost. 3. Paralysis of lumbrical muscles 1 and 2 occurs so that flexion of the index and middle fingers at the metacarpophalangeal joint is lost. 4. Paralysis of the abductor pollicis brevis, opponens pollicis and flexor pollicis brevis muscles occurs so that oppostion and flexion of the thumb are lost. 5. Sensory loss occurs on the palmar and dorsal aspects of the index finger, middle finger and half of the ring finger and on the palmar aspect of the thumb. 6. Clinically, the thenar eminence is flattened ( ape hand) , and when the patient is asked to make a fist, the index and middle fingers remain straight while the ring and little fingers flex ( benediction hand ).
Median Nerve Median nerve injury at the wrist 1. The median nerve may be injured by slashing of the wrist or carpal tunnel syndrome. The nerve may also be compromised by a dislocation of the lunate bone. 2. The muscles in the flexor compartment of the arm are not paralyzed. 3. Paralysis of lumbrical muscles 1 and 2 occurs so that flexion of the index and middle fingers at the MP joint is weakened. 4. Paralysis of the abductor pollicis brevis, opponens pollicis, and flexor pollicis brevis muscles occurs so that opposition of the thumb is lost. Flexion and abduction are weakened. 5. Sensory loss occurs on the palmar and dorsal aspects of the index finger, middle finger, and half of the ring finger, and on the palmar aspect of the thumb. 6. Clinically, the thenar eminence is flattened (ape hand)
Ulnar Nerve A
Radial Nerve C
Scaphoid-most commonly broken-associated with pain in the anatomical snuff box Lunate- most commonly dislocated Compresses median nerve
Case 1 History: A 24-year-old man comes into the emergency department complaining of pain after a fall onto his outstretched right hand. The patient has no complaints besides right hand pain, is otherwise healthy, and takes no medications. His past medical history is unremarkable. Physical Exam: When examining the right hand, you note that the patient has pain and deep tenderness in the anatomical snuff-box. Motor function and sensation are intact, and the rest of the exam is unremarkable.
Case 2 History: A 44-year-old woman comes into the office with a chief complaint of pain, numbness, tingling, and clumsiness in her right hand. She says the symptoms began a few months ago and have been getting worse, to the point where they are starting to interfere with her work as a typist. The patient has strong and sometimes painful tingling sensations in the thumb, index, and middle fingers and the lateral (radial) side of her palm, which she says makes her feel as though her hands have “fallen asleep”. The woman also experiences numbness in the same areas. At times, the patient has dropped items she was holding in her hand because of hand weakness and clumsiness. The woman’s past medical history is unremarkable. She takes no medications and has not been sexually active in the last few years. Family history is unremarkable. Physical Exam: The patient is fit and healthy appearing. Head, neck, chest, abdomen, and lower extremity exams are normal. The patient has sensory loss in the thumb and first two and a half fingers of her right hand. Some thenar muscle atrophy and weakness also is noted in the right hand. Percussion of the volar (palmar) aspect of the distal right wrist reproduces the patient’s typical tingling symptoms. The remainder of the exam is unremarkable.
Case 3 History: You are called to see two different patients in your office, both with symptoms in their left upper extremities from a car accident several months ago. Patient 1 had a midshaft fracture of the left humerus at the time of the accident, and patient 2 sustained a fracture of the medial epicondyle of the distal left humerus. Physical Exam: Patient 1 has wristdrop with weakness of forearm, wrist, and hand extension. She also has weakness of abduction and adduction of the hand and sensory loss over the back (dorsal aspect) of the thumb, first two fingers, and lateral hand (area C in the figure). Patient 2 has a clawhand, with hyperextension of the fourth and fifth fingers at the metacarpophalangeal joints and flexion at the interphalangeal joints. He also has weakness of finger abduction and adduction and loss of thumb adduction and sensory loss over the area labeled A in the figure.
Case 4 History: A 45-year-old right-handed man complains of pain and weakness in his right shoulder. He thinks he may have injured his shoulder while throwing a ball back and forth with his son, but admits he had some pain in his shoulder before the throwing injury, which occurred one week ago. The patient says that his shoulder is weak when he tries to lift it from his side. The patient is otherwise healthy, has no known medical problems, and takes no regular medications. He works in construction, where he does a lot of lifting and heavy manual labor. The patient does not drink alcohol or smoke tobacco. Family history is notable for hypertension. Physical Exam: Vital signs are normal. Neurologic exam is normal, and reflexes are normal in all four extremities. When comparing the two sides, you notice considerable weakness in the first 15 degrees of abduction in the right shoulder compared with the left. If you passively lift the right shoulder into 150 of abduction, the patient has normal strength and ability to move the shoulder into greater degrees of abduction, although this action causes the patient to have pain in his shoulder. The rest of the exam is unremarkable.
Level Landmark T2 Jugular Notch T3 Base of scapular spine Top of aortic arch T4 Sternal angle Second costal cartilage Trachea bifurcation Upper end of ascending aorta Beginning of descending aorta Arch of azygos vein and its entrance into superior vena cava T7 Inferior angle of scapula T8 Inferior vena cava hiatus T9 Xiphoid process T10 Esophageal hiatus T12 Aortic hiatus
CN I Olfactory Nerve Asnomia Cribiform plate of ethmoid bone Special sensory - smell
CN II Optic Nerve Special sensory - vision Optic canal (sphenoid) Ophthalmic artery Vision deficits
CN III Oculomotor Nerve Motor Levator palpebrae superioris Superior rectus Medial rectus Inferior rectus Inferior oblique Parasympathetic Ciliary ganglion Ptosis Gaze would be directed laterally and down Dilated pupil Sphincter pupillae Ciliaris muscle Superior orbital fissure (sphenoid)
CN IV Trochlear Nerve Motor Superior oblique Lesion results in difficulty in looking medially and down as in walking down stairs Superior orbital fissure (sphenoid)
CN V Trigeminal Nerve CN V 1 Ophthalmic Nerve Superior orbital fissure (sphenoid) General Sensory Cornea – afferent limb of blink reflex Orbit Forehead and scalp to bregma Skin of nose Frontal and ethmoid sinuses
CN V 2 Maxillary Nerve Foramen rotundum (sphenoid) General Sensory Nasal mucosa Maxillary sinus Teeth of the upper jaw Hard and soft palate Cheek Upper lip
CN V 3 Mandibular Nerve Foramen ovale (sphenoid) General Sensory Teeth of lower jaw TMJ Ant. 2/3 of tongue Skin over the mandible and temporal region
CN V 3 Mandibular Nerve Motor Medial Pterygoid Mylohyoid Lateral Pterygoid Anterior Belly of Digastric Masseter Tensor tympani Temporalis Tensor veli palatini Upon opening of mouth - deviation of jaw toward the side of the lesion
CN VI Abducens Nerve Motor Lateral Rectus Superior orbital fissure (sphenoid) Lesion results in a medial strabismus
CN VII Facial Nerve Internal acoustic meatus (Temporal) Special Sensory Taste for ant. 2/3 of tongue Motor Stapedius Stylohyoid Posterior belly of digastric Muscles of facial expression Hyperacousia Bell’s palsy
CN VII Facial Nerve Parasympathetic Pterygopalatine ganglion Submandibular ganglion Secretomotor to lacrimal gland and to nasal mucosa Secretomotor to submandibular and sublingual glands Lack of secretion from the lacrimal gland
CN VIII Vestibulorcochlear Nerve Internal acoustic meatus (Temporal) Special sensory – Hearing and Balance Lesion results in hearing deficits and vertigo
CN IX Glossopharyngeal Nerve Jugular Foramen Special Sensory Stylopharyngeus General Sensory Post. 1/3 of tongue Middle ear Pharyngeal plexus Motor Taste for post. 1/3 of tongue Parasympathetic Secretomotor to the parotid gland Afferent limb of the gag reflex
CN X Vagus Nerve Jugular Foramen Special Sensory Muscles of the soft palate Pharyngeal constrictors Muscles of the larynx General Sensory Vallecula epigloticca Piriform recess Larynx Motor Taste in area of epiglottis Parasympathetic Smooth muscle of digestive tract to the distil 1/3 of transverse colon s Secretomotor to the digestive tract Heart Lungs Afferent limb of the cough reflex Efferent limb of the gag reflex Efferent limb of the cough reflex
CN XI Accessory Nerve Enters skull - Foramen magnum Exits- Jugular Foramen Sternocleidomastoid Trapezius Motor Lesion results in weakness in ability to shrug shoulder
CN XII Hypoglossal Nerve Hypoglossal canal (Occipital) Intrinsic tongue muscles Hyoglossus Styloglossus Genioglossus Motor Lesion results in deviation of the protruded tongue to the side of damage
Pterion Subarachnoid Hematoma Ruptured berry aneurysm in the Circle of Willis Subdural Hematoma Head trauma that tears the “bridging” cerebral veins Epidural Hematoms Trauma on lateral aspect of skull-tearing the middle meningeal artery.
Venous Drainage and Cavernous Sinus Thrombosis Cavernous Sinus Ophthalmic Veins Facial Vein Deep Facial Vein Pterygoid Plexus of Veins
Openings in the Lateral Wall of Nasal Cavity Sphenoid Sinus Posterior Ethmoidal Air Cells Ethmoidal Bulla Middle Ethmoidal Air Cells Hiatus Semilunaris Maxillary Sinus Infundibulum Anterior Ethmoidal Air Cells Frontal Sinus Nasolacrimal Duct SER Sphenioethmoidal Recess SER SM Superior Meatus SM MM Middle Meatus MM 1 1 2 2 3 3 IM Inferior Meatus IM
Salivary Glands Sublingual gland Submandibular gland Parotid gland Empties into vestibule opposite the second upper molar tooth Empties directly into floor of oral cavity via multiple openings Mylohyoid Empties just lateral to the frenulum at the sublingual caruncle
Thyroid Gland Surgery Superior Thyroid Artery and External Laryngeal nerve (Cricothyroid muscle) Inferior Thyroid Artery and Recurrent Laryngeal nerve ( All laryngeal muscles except the cricothyroid)
Gag reflex Afferent CN IX Efferent CN X Cough reflex Afferent CN X Efferent CN X Blink reflex Afferent CN V 1 Efferent CN VII
Case 5 History: A 44-year-old woman complains that her face looks “funny”, especially when she smiles. The woman says her symptoms began a few weeks ago and have gotten worse. She mentions that everything sounds loud in her right ear, which started about the same time as her facial symptoms. The patient also mentions that she is unable to whistle, which she can usually do. The patient is fit and in no acute distress. She denies fever, headache, sick contacts, and other neurologic symptoms. The patient has no significant past medical history; takes no medications; and does not use alcohol, tobacco, or drugs. Family history is unremarkable. Physical Exam: You note flattening of the right nasolabial fold and a slight right facial droop. The patient is unable to close her right eye completely or wrinkle her right forehead. With smiling, an obvious asymmetry of the face is noted, as the right side of the patient’s lips do not curl upward like the left side. On hearing testing, the patient is bothered by sounds in her right ear because they seem very loud to her. No sensory loss in the face is demonstrable. The remainder of the exam is unremarkable.
Common Peroneal Nerve
Superior gluteal nerve injury 1. The superior gluteal nerve may be injured during surgery, posterior dislocation of the hip, or poliomyelitis. 2. Paralysis of the gluteus medius and gluteus minimus occurs so that the ability to pull the pelvis down and abduction of the thigh is lost. 3. Clinically, the patient demonstrates a positive Trendelenberg sign , which is tested as follows. The patient stands with his or her back to the examiner and alternately raises each foot off the ground. If the superior gluteal nerve on the left side is injured, the right pelvis falls downward when the patient raises the right foot off the ground. A Trendelenberg sign also can be observed in a patient with a hip dislocation or fracture of the neck of the femur.
NAVEL Relationship of structures in the femoral triangle Femoral Nerve Femoral Artery Femoral Vein Empty Space Lymphatics
THAND Tibialis Anterior Extensor Hallucis Longus Dorsalis Pedis Deep Peroneal Nerve Extensor Digitorium Longus Relationship of structures on the dorsum of the foot
Relationship of structures on the medial side of ankle Tom, Dick and Harry Tibialis Posterior Flexor Digitorium Longus Posterior Tibial Artery Tibial Nerve Flexor Hallucis Longus
Development of the Thyroid Gland Descends in neck, anterior to hyoid bone and laryngeal cartilages Initially, connected to foramen cecum by thyroglossal duct At seven weeks, has assumed its final shape and position