- Steppage gait (HP:0003376): An abnormal gait pattern that arises from weakness of the pretibial and peroneal muscles due to a lower motor neuron lesion. Affected patients have footdrop and are unable to dorsiflex and evert the foot. The leg is lifted high on walking so that the toes clear the ground, and there may be a slapping noise when the foot strikes the ground again. Evidence: IEA. (OMIM:606595)
- Middle age onset (HP:0003596): A type of adult onset with onset of symptoms at the age of 40 to 60 years. Evidence: PCS. Frequency: 4/7. (PMID:15122254)
- Decreased motor nerve conduction velocity (HP:0003431): A type of decreased nerve conduction velocity that affects the motor neuron. Evidence: PCS. (PMID:15122254)
- Ulnar claw (HP:0001178): An abnormal hand position characterized by hyperextension of the fourth and fifth fingers at the metacarpophalangeal joints and flexion of the interphalangeal joints of the same fingers such that they are curled towards the palm. Evidence: IEA. (OMIM:606595)
- Pes cavus (HP:0001761): An increase in height of the medial longitudinal arch of the foot that does not flatten on weight bearing (i.e., a distinctly hollow form of the sole of the foot when it is bearing weight). Evidence: PCS. Frequency: 6/7. (PMID:15122254)
- Late onset (HP:0003584): A type of adult onset with onset of symptoms after the age of 60 years. Evidence: PCS. Frequency: 1/7. (PMID:15122254)
- Muscle spasm (HP:0003394): Sudden and involuntary contractions of one or more muscles. Evidence: PCS. Frequency: 1/7. (PMID:15122254)
- Distal muscle weakness (HP:0002460): Reduced strength of the musculature of the distal extremities. Evidence: PCS. Frequency: 7/7. (PMID:15122254)
- Fasciculations (HP:0002380): Fasciculations are observed as small, local, involuntary muscle contractions (twitching) visible under the skin. Fasciculations result from increased irritability of an axon (which in turn is often a manifestation of disease of a motor neuron). This leads to sporadic discharges of all the muscle fibers controlled by the axon in isolation from other motor units. Evidence: PCS. Frequency: 1/7. (PMID:15122254)
- Claw hand deformity (HP:0034337): An abnormality of the hand characterized by metacarpophalangeal (MCP) hyperextension and proximal interphalangeal (PIP) and distal interphalangeal (DIP) flexion. The position of the affected hand is said to resemble a claw. Evidence: PCS. Frequency: 3/7. (PMID:15122254)
- Foot dorsiflexor weakness (HP:0009027): Weakness of the muscles responsible for dorsiflexion of the foot, that is, of the movement of the toes towards the shin. The foot dorsiflexors include the tibialis anterior, the extensor hallucis longus, the extensor digitorum longus, and the peroneus tertius muscles. Evidence: PCS. (PMID:15122254)
- Distal sensory impairment (HP:0002936): An abnormal reduction in sensation in the distal portions of the extremities. Evidence: PCS. (PMID:15122254)
- Chronic axonal neuropathy (HP:0007267): An abnormality characterized by chronic impairment of the normal functioning of the axons. Evidence: PCS. (PMID:15122254)
- Late young adult onset (HP:0025710): Onset of disease at an age of greater than or equal to 25 to under 40 years. Evidence: PCS. Frequency: 2/7. (PMID:15122254)
- Hyporeflexia of upper limbs (HP:0012391): Reduced intensity of muscle tendon reflexes in the upper limbs. Reflexes are elicited by stretching the tendon of a muscle, e.g., by tapping. Evidence: PCS. Frequency: 4/7. (PMID:15122254)
- Upper limb amyotrophy (HP:0009129): Muscular atrophy involving the muscles of the upper limbs. Evidence: PCS. Frequency: 7/7. (PMID:15122254)
- Autosomal dominant inheritance (HP:0000006): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: PCS. (PMID:15122254)
- Areflexia of lower limbs (HP:0002522): Inability to elicit tendon reflexes in the lower limbs. Evidence: PCS. Frequency: 6/7. (PMID:15122254)
- Distal lower limb amyotrophy (HP:0008944): Muscular atrophy of distal leg muscles. Evidence: PCS. Frequency: 7/7. (PMID:15122254)
These phenotypes are associated with the disease Charcot-Marie-Tooth disease axonal type 2F (OMIM:606595).