14 year-old right handed boy presents to clinic with his parents for weakness. He has never been particularly athletic but in the last few years has noted progressive difficulty keeping up with his peers in gym class. In the last few months he has noticed slight difficulties climbing stairs and reaching over his head. He denies chest pain, trouble swallowing, and numbness/tingling of his extremities.
Family history: one maternal uncle who began to need a wheelchair in his 20s and died of cardiac causes in his 40s.
SHx: Identifies as Samoan, no substance use
Vitals: T 37, BP 120/70, HR 90 and irregularly irregular, RR 12, O2 sat 99% RA.
General Exam: appears stated age, no acute distress, non-dysmorphic
Neurologic Exam:
Mental status: Alert, oriented, answers questions appropriately, language fluent
CN: Normal facial strength and sensation. Normal tongue strength
Motor: disproportionately large calf muscle bulk. Tone slightly low. Strength is 4/5 at neck flexors, deltoids and hip flexors and otherwise 5/5. Not fatiguable weakness.
Sensory: normal sensation to light touch, pinprick and vibration
Reflexes: 1+ and symmetric throughout. Toes downgoing.
Coordination: No ataxia Gait: Gait with a slight waddling quality. Able to stand on heels and toes. Uses Gower’s maneuver when asked to stand up from floor.