Clinical and laboratory findings of Nonaka distal myopathy in two Chinese patients
| Case II-2 | Case II-3 | |
|---|---|---|
| *+, 0–25%; ++, 25–50%; +++, 50–75%; ++++, 75–100%. | ||
| Sex | Male | Female |
| Age, years | 50 | 41 |
| Age of onset, years | 30 | 26 |
| Inheritance | Autosomal recessive | Autosomal recessive |
| Initial weakness | Foot drop | Foot drop |
| Distribution of weakness and severity | ||
| Severe | Anterior distal legs | Anterior and posterior distal legs |
| Moderate | Posterior distal legs and posterior thigh | Anterior and posterior thigh, upper limbs |
| Mild | Upper limbs | Neck flexor muscles |
| Medical Research Council (MRC) scales | ||
| Quadriceps | 5 | 2 |
| Hamstrings | 4 | 1 |
| Tibialis anterior | 1 | 0 |
| Gastrocnemius | 4 | 1 |
| Quadriceps sparing | Yes | No |
| Creatine kinase (reference range 50–130 IU/l) | 322 | 177 |
| Electromyography | Mixed myopathic and some neuropathic changes | Myopathic changes |
| Magnetic resonance imaging fatty infiltration* | ||
| Quadriceps | − | ++ ∼ +++ |
| Hamstrings | + ∼ ++ | +++ ∼ ++++ |
| Tibialis anterior | + ∼ ++ | ++++ |
| Gastrocnemius | − ∼ + | +++ ∼ ++++ |
| Muscle biopsy | Mild variation in fibre size, many rimmed vacuoles | Mild variation in fibre size, many rimmed vacuoles |
| Current status | Walks with assistance | Wheelchair bound |