Hemiballism describes a sudden, uncontrolled flinging movement; this occurs if there is damage/destruction of subthalamic nuclei. Chorea is an abnormal, involuntary movement that can be seen in Huntington's disease; it occurs after destruction of the caudate nucleus. Dystonias are abnormal movements and are most often referred to as resting tremors of Parkinson's disease. Parkinsons disease results from a loss of dopamine from the substantia nigra. 

A dermatome is an area of skin supplied by a single spinal nerve. Along the thorax and abdomen the dermatomes are stacked like coins/discs, each layer supplied by a different spinal nerve. Along the arms and legs the pattern is different. Symptoms that follow a dermatome may indicate a pathology that involves the nerve root. There are a number of important dermatomes one being the inguinal region innervated by the L1 nerve root.

A dermatome is an area of skin supplied by a single spinal nerve. Along the thorax and abdomen the dermatomes are stacked like coins/discs, each layer supplied by a different spinal nerve. Along the arms and legs the pattern is different. Symptoms that follow a dermatome may indicate a pathology that involves the nerve root. There are a number of important dermatomes one being the layer of the umbilicus innervated by the T10 nerve root.

Because comatose patients cannot visually track objects, brainstem function is assessed by testing the oculocephalic reflex. Making sure any cervical spine pathology, the patients eyelids are held open, and her head is turned to side. If the eyes move in the opposite direction, the oculocephalic reflex is said to be positive, and indicates that there is some intact brainstem function. Because it is reminiscent of the way a doll's eyes move, this test is sometimes called a doll's eyes test. 

An upper motor neuron lesion is an injury to the motor pathways of the central nervous system, before the level of the cranial nerve nuclei, or the ventral horn of the spinal cord. The key to this question is that the patient is an adult; in children, under the age of 2, a positive Babinski sign is a normal finding. However, a positive crossed adductor reflex, a positive pronator drift sign, and a positive Hoffman's reflex are always pathological, and may indicate an upper motor neuron lesion.

The anterior compartment of the thigh is a fascial compartment that contains groups of muscles with their blood supply and nerves. The anterior compartment contains the sartorius muscle and the quadriceps muscles (rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis). The iliopsoas is sometimes considered a component of the anterior compartment of the thigh. The function of the muscles of the anterior compartment is to extend the knee and flex the hip. The anterior compartment is innervated by the femoral nerve (however, the iliopsoas is not innervated by the femoral nerve and is innervated by ventral rami of L1-L3). The blood supply of the anterior compartment is the femoral artery. The femoral artery supplies blood to the anterior compartment and is the largest blood vessel of the lower limb.

Eye movements are controlled by cranial nerves (CN) 3,4, and 6 (oculomotor, trochlear, and abducens). Helpful Hint** - A nice and easy way to remember this is the following: (LR6SO4)3 = which means that Abducens CN 6 innervates the lateral rectus muscle, Trochlear CN 4 innervates the superior oblique muscle, and Oculomotor CN 3 innervates the rest of the eye muscles.

Trigeminal CN 5 is responsible for the muscles that control mastication (chewing). It is a common error to suspect facial CN 7 due to its innervation of the facial muscles involved with expressions. However, the trigeminal nerve is unique because although it provides sensory to the face, it is also responsible for motor function involved with chewing.

These findings suggest that the patient is experiencing Bell's palsy. This is a common finding with the lower motor neuron lesion of facial CN 7. We ask the patient to raise their eye brows to distinguish Bell's palsy from a stroke. If a patient has half sided facial paralysis and can raise both eyebrows this is usually a red flag.

Compression of the S1 nerve root can lead to weakness in gastrocnemius, peroneus longus, and peroneus brevis muscles causing difficulty with foot push off during walking. The S1 nerve root is also responsible for sensation along the lateral foot, and compression could cause numbness and/or tingling. The achilles reflex (ankle jerk reflex) tests the S1 nerve root.