- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1216)
- Joint stiffness (HP:0001387): Joint stiffness is a perceived sensation of tightness in a joint or joints when attempting to move them after a period of inactivity. Joint stiffness typically subsides over time. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1216)
- Distal amyotrophy (HP:0003693): Muscular atrophy affecting muscles in the distal portions of the extremities. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1216)
- Cachexia (HP:0004326): Severe weight loss, wasting of muscle, loss of appetite, and general debility related to a chronic disease. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1216)
- Nonprogressive muscular atrophy (HP:0008964): Muscular atrophy that does not display a progression in severity with time. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1216)
These phenotypes are associated with the disease Autosomal dominant congenital benign spinal muscular atrophy (ORPHA:1216).