- Clonus (HP:0002169): A series of rhythmic and involuntary muscle contractions (at a frequency of about 5 to 7 Hz) that occur in response to an abruptly applied and sustained stretch. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:319199)
- Upper limb hyperreflexia (HP:0007350): Increased intensity of the a reflex in the arm. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:319199)
- Delayed speech and language development (HP:0000750): A degree of language development that is significantly below the norm for a child of a specified age. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:319199)
- Pectus carinatum (HP:0000768): A deformity of the chest caused by overgrowth of the ribs and characterized by protrusion of the sternum. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:319199)
- Joint hypermobility (HP:0001382): The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:319199)
- Kyphosis (HP:0002808): Exaggerated anterior convexity of the thoracic vertebral column. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:319199)
- Upper limb hypertonia (HP:0200049): Increased muscle tone observed in the arms of the affected person. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:319199)
- Hearing impairment (HP:0000365): A decreased magnitude of the sensory perception of sound. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:319199)
- Limb dystonia (HP:0002451): A type of dystonia (abnormally increased muscular tone causing fixed abnormal postures) that affects muscles of the limbs. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:319199)
- Impaired vibratory sensation (HP:0002495): A decrease in the ability to perceive vibration. Clinically, this is usually tested with a tuning fork which vibrates at 128 Hz and is applied to bony prominences such as the malleoli at the ankles or the metacarpal-phalangeal joints. There is a slow decay of vibration from the tuning fork. The degree of vibratory sense loss can be crudely estimated by counting the number of seconds that the examiner can perceive the vibration longer than the patient. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:319199)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:319199)
- Abnormal auditory canal morphology (HP:0000372): Any structural abnormality of the external acoustic tube (also known as the auditory canal). Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:319199)
- Failure to thrive (HP:0001508): Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:319199)
- Ventriculomegaly (HP:0002119): An increase in size of the ventricular system of the brain. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:319199)
- Cortical dysplasia (HP:0002539): The presence of developmental dysplasia of the cerebral cortex. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:319199)
- Impaired proprioception (HP:0010831): A loss or impairment of the sensation of the relative position of parts of the body and joint position. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:319199)
These phenotypes are associated with the disease Autosomal recessive spastic paraplegia type 53 (ORPHA:319199).