-The ulnar nerve innervates the muscles in the hypothenar aspect of the palm of the hand, namely the flexor digiti minimi, abductor digiti minimi, and opponens digiti minimi.
-In addition, the ulnar nerve innervates other intrinsic muscles, including the interossei, the two medial lumbrical muscles, and the adductor pollicis.
- These muscles function to keep the metacarpals tightly together when performing gripping tasks, making the ulnar nerve responsible for power of the hand.
- However, by virtue of its innervation of the adductor pollicis, it is also responsible for adduction of the thumb, which is required when pulling an object with the thumb and index finger, such as the piece of paper.
- *Without the adductor pollicis, the thumb flexors will attempt to substitute, and this will result in
inadvertent flexion of the thumb, losing the grip between the thumb and index finger.
In formal testing, this is referred to as Froment sign*.
1. Mitochondrial disorders result from genetically inherited or spontaneous mutations in the DNA that lead to impaired function of proteins found within the mitochondria.
Symptoms include loss of muscle coordination, muscle weakness, visual and hearing problems, and learning disabilities.
2. Phenylketonuria is an autosomal recessive condition in which a mutation occurs in a gene responsible for breaking down the amino acid phenylalanine.
Symptoms will typically present within a few months of birth as the phenylalanine accumulates. If left untreated, severe mental retardation will occur.
3. Osteogenesis-imperfecta is a genetic-used to delineate specific types of OI- connective tissue disorder that affects the formation of collagen during bone development.
Symptoms include pathological fractures, osteoporosis, and weakness.
4. Wilson's disease is an autosomal recessive inherited trait that produces a defect in the body's ability to metabolize copper.
The copper accumulates over time within the brain, liver, cornea, kidney, and other tissues.
1. Crushing chest pain or tightness, which may radiate, and is present for greater than 30 minutes is typically the hallmark symptom of a myocardial infarction (MI).
Other signs and symptoms may include anxiety, dyspnea, syncope, nausea, arrhythmia, diaphoresis, and an impending sense of doom.
2. Complaints of dull chest pain or tightness, which may be accompanied by a burning sensation (i.e., heartburn) are associated with gastroesophageal reflux disease (GERD).
GERD, however, does not typically cause diaphoresis or dyspnea.
3. Chest pain complaints associated with pneumothorax are typically described as "sharp" or "sudden," are somewhat localized, and do not present substernally.
Dyspnea complaints may be mild to severe depending on the size of the pneumothorax.
4. A pulmonary embolism (PE) of significant size may simulate a MI with common symptoms including chest pain, anxiety, dyspnea, and a sense of doom.
A patient with PE would be unlikely to present with vagal related symptoms (e.g., nausea, diaphoresis), however, would commonly exhibit cyanosis.