- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:610)
- Flexion contracture (HP:0001371): A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:610)
- EMG: myopathic abnormalities (HP:0003458): The presence of abnormal electromyographic patterns indicative of myopathy, such as small-short polyphasic motor unit potentials. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:610)
- Muscular dystrophy (HP:0003560): The term dystrophy means abnormal growth. However, muscular dystrophy is used to describe primary myopathies with a genetic basis and a progressive course characterized by progressive skeletal muscle weakness and wasting, defects in muscle proteins, and histological features of muscle fiber degeneration (necrosis) and regeneration. If possible, it is preferred to use other HPO terms to describe the precise phenotypic abnormalities. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:610)
- Progressive proximal muscle weakness (HP:0009073): Lack of strength of the proximal muscles that becomes progressively more severe. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:610)
- Reduced muscle collagen VI (HP:0030095): A decreased amount of collagen VI in muscle tissue. Collagen VI is a primarily associated with the extracellular matrix of skeletal muscle. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:610)
- Neck muscle weakness (HP:0000467): Decreased strength of the neck musculature. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Interphalangeal joint contracture of finger (HP:0001220): Chronic loss of joint motion in an interphalangeal joint of a finger due to structural changes in non-bony tissue. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Wrist flexion contracture (HP:0001239): A chronic loss of wrist joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevent normal movement of the joints of the wrist. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Distal muscle weakness (HP:0002460): Reduced strength of the musculature of the distal extremities. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Multiple joint contractures (HP:0002828). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Elevated circulating creatine kinase activity (HP:0003236): The activity of creatine kinase in the blood circulation is above the upper limit of normal. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Limb-girdle muscle weakness (HP:0003325): Weakness of the limb-girdle muscles (also known as the pelvic and shoulder girdles), that is, lack of strength of the muscles around the shoulders and the pelvis. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Quadriceps muscle weakness (HP:0003731): Weakness of the quadriceps muscle (that is, of the muscle fasciculus of quadriceps femoris). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Ankle flexion contracture (HP:0006466). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Increased muscle lipid content (HP:0009058): An abnormal accumulation of lipids in skeletal muscle. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Camptodactyly of finger (HP:0100490): The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers cannot be extended to 180 degrees by either active or passive extension. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
- Hyperkeratosis (HP:0000962): Hyperkeratosis is a histopathological term defining a thickened stratum corneum and may be present in many different skin conditions, with many possible overlaps. Hyperkeratosis refers to the increased thickness of the stratum corneum, the outer layer of the skin. Hyperkeratosis is subclassified as orthokeratotic or parakeratotic. Orthokeratotic hyperkeratosis refers to the thickening of the keratin layer with preserved keratinocyte maturation, while parakeratotic hyperkeratosis shows retained nuclei as a sign of delayed maturation of keratinocytes. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Cigarette-paper scars (HP:0001073): Thin (atrophic) and wide scars. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- 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: Occasional (HP:0040283). (ORPHA:610)
- Achilles tendon contracture (HP:0001771): A contracture of the Achilles tendon. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Abnormality of the respiratory system (HP:0002086): An abnormality of the respiratory system, which include the airways, lungs, and the respiratory muscles. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- 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. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Hypoventilation (HP:0002791): A reduction in the amount of air transported into the pulmonary alveoli by breathing, leading to hypercapnia (increase in the partial pressure of carbon dioxide). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Lumbar hyperlordosis (HP:0002938): An abnormal accentuation of the inward curvature of the spine in the lumbar region. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Elbow flexion contracture (HP:0002987): An elbow contracture that limits the ability of the elbow joint to be extended (straightened), meaning that the elbow is fixed in an flexed (bent) position. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Spinal rigidity (HP:0003306): Reduced ability to move the vertebral column with a resulting limitation of neck and trunk flexion. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Axial muscle weakness (HP:0003327): Reduced strength of the axial musculature (i.e., of the muscles of the head and neck, spine, and ribs). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Gowers sign (HP:0003391): A phenomenon whereby patients are not able to stand up without the use of the hands owing to weakness of the proximal muscles of the lower limbs. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Scapular winging (HP:0003691): Abnormal protrusion of the scapula away from the surface of the back. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Generalized amyotrophy (HP:0003700): Generalized (diffuse, unlocalized) amyotrophy (muscle atrophy) affecting multiple muscles. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Rimmed vacuoles (HP:0003805): Presence of abnormal vacuoles (membrane-bound organelles) in the sarcolemma. On histological staining with hematoxylin and eosin, rimmed vacuoles are popcorn-like clear vacuoles with a densely blue rim. The vacuoles are often associated with cytoplasmic and occasionally intranuclear eosinophilic inclusions. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Curved toe phalanx (HP:0010176): A deviation from the normal straight form of one or more toe phalanges. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Reduced maximal expiratory pressure (HP:0012497): A decrease in the maximum amount of pressure of expired air achieved by a person after a full inspiration. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Keratosis pilaris (HP:0032152): An anomaly of the hair follicles of the skin that typically presents as small, rough, brown folliculocentric papules distributed over characteristic areas of the skin, particularly the outer-upper arms and thighs. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:610)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:610)
These phenotypes are associated with the disease Bethlem muscular dystrophy (ORPHA:610).