Phenotypes associated with the disease autosomal dominant childhood-onset proximal spinal muscular atrophy without contractures (OMIM:158600):
- Abnormal foot morphology (HP:0001760): An abnormality of the skeleton of foot. Evidence: TAS. (OMIM:158600)
- EMG: neuropathic changes (HP:0003445): The presence of characteristic findings of denervation on electromyography (fibrillations, positive sharp waves, and giant motor unit potentials). Evidence: TAS. (OMIM:158600)
- Decreased patellar reflex (HP:0011808): Decreased intensity of the patellar reflex (also known as the knee jerk reflex). Evidence: TAS. (OMIM:158600)
- Delayed ability to walk (HP:0031936): A failure to achieve the ability to walk at an appropriate developmental stage. Most children learn to walk in a series of stages, and learn to walk short distances independently between 12 and 15 months. Evidence: IEA. (OMIM:158600)
- Somatic sensory dysfunction (HP:0003474): An abnormality of the primary sensation that is mediated by peripheral nerves (pain, temperature, touch, vibration, joint position). The word hypoesthesia (or hypesthesia) refers to a reduction in cutaneous sensation to a specific type of testing. Evidence: TAS. (OMIM:158600)
- Global developmental delay (HP:0001263): A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age. Evidence: TAS. Frequency: Occasional (HP:0040283). (OMIM:158600)
- Type 2 muscle fiber predominance (HP:0010602): An abnormal predominance of type II muscle fibers (in general, this feature can only be observed on muscle biopsy). Evidence: TAS. (OMIM:158600)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: TAS. (OMIM:158600)
- Difficulty running (HP:0009046): Reduced ability to run. Evidence: TAS. (OMIM:158600)
- Proximal lower limb muscle weakness (HP:0008994): A lack of strength of the proximal muscles of the legs. Evidence: TAS. (OMIM:158600)
- Waddling gait (HP:0002515): Weakness of the hip girdle and upper thigh muscles, for instance in myopathies, leads to an instability of the pelvis on standing and walking. If the muscles extending the hip joint are affected, the posture in that joint becomes flexed and lumbar lordosis increases. The patients usually have difficulties standing up from a sitting position. Due to weakness in the gluteus medius muscle, the hip on the side of the swinging leg drops with each step (referred to as Trendelenburg sign). The gait appears waddling. The patients frequently attempt to counteract the dropping of the hip on the swinging side by bending the trunk towards the side which is in the stance phase (in the German language literature this is referred to as Duchenne sign). Similar gait patterns can be caused by orthopedic conditions when the origin and the insertion site of the gluteus medius muscle are closer to each other than normal, for instance due to a posttraumatic elevation of the trochanter or pseudarthrosis of the femoral neck. Evidence: TAS. (OMIM:158600)
- Spinal muscular atrophy (HP:0007269): Muscular weakness and atrophy related to loss of the motor neurons of the spinal cord and brainstem. Evidence: TAS. (OMIM:158600)
- 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: TAS. (OMIM:158600)
- Proximal lower limb amyotrophy (HP:0008956): Muscular atrophy affecting proximally located muscles of the legs, i.e., of the thigh. Evidence: TAS. (OMIM:158600)
- Slowly progressive (HP:0003677): Applies to a disease manifestation that only slowly increases in scope or severity over the course of time. Evidence: TAS. (OMIM:158600)