Improvement of muscle strength after treatment for hyperparathyroidism.

Severe muscular weakness and increased fatigability are occasionally encountered in patients with hyperparathyroidism (HPT). An unselected series of 15 HPT patients was studied to assess if subjective fitness could be associated with detectable muscular dysfunction at objective measurements comparing muscle strength before and after surgery. Significant increase in isokinetic strength of knee extension and knee flexion at higher angular velocities was found three months after surgery, suggesting effect predominantly on type II (fast twitch) muscle fibres. The results of the study support the clinical impression that HPT surgery may be beneficial to patients with muscular symptoms.