proximal muscle weakness

Introduction

Weakness of muscles controlling movement of the hip & shoulder.

Etiology

• osteomalacia
• dermatomyositis
• polymyositis (rapidly progressive)
• Lambert-Eaton syndrome
• Cushing's syndrome
• hypothyroidism (late manifestation)
• hyperthyroidism
• hyperparathyroidism
• vitamin D deficiency
• colchicine
• long-term glucocorticoid

* if both proximal muscle weakness & distal muscle weakness, consider inclusion body myositis

Clinical manifestations

• bilateral proximal muscle weakness suggests myopathy

* impaired effort & strength in deltoids & hip flexors secondary to pain does not constitute proximal muscle weakness

Differential diagnosis

• polymyalgia rheumatica
  • bilateral shoulder pain, neck pain & hip pain that may be described as impaired effort & strength in deltoids & hip flexors secondary to pain

More general terms

• muscle weakness