179ms
Updated: 6/17/2021

Osteomalacia

0%
Topic
Review Topic
0
0
Topic
Images
https://devupload.orthobullets.com/topic/9033/images/looser zone.jpg
https://devupload.orthobullets.com/topic/9033/images/patho frac fem neck.jpg
https://devupload.orthobullets.com/topic/9033/images/histo osteomalacia.jpg
https://devupload.orthobullets.com/topic/9033/images/histo osteoid.jpg
  • summary
    • Osteomalacia is a metabolic bone disease where defective mineralization results in a large amount or unmineralized osteoid.
    • Diagnosis is made based on a thorough evaluation of serum labs, clinical features, and radiographic findings.
    • Treatment involves medical management with Vitamin D supplementation and resolving the underlying etiology.
  • Etiology
    • Mechanism
      • qualitative defect as opposed to a quanitative defect like osteoporosis
  • Epidemiology
    • Incidence
      • rare in the US (approximately 1 in 1000)
        • much less common than osteoporosis
        • because of adequate exposure to sunlight and dairy products fortified with vitamin D
    • Demographics
      • rickets is found in children (open physis)
      • osteomalacia is found in adults (closed physis)
    • Risk factors
      • the following conditions predispose a patient to osteomalacia
        • vitamin-D deficient diets
        • malabsorption e.g. celiac disease
        • renal osteodystrophy
        • hypophosphatemia
        • chronic alcoholism
        • tumors (tumor-induced osteomalacia)
        • drugs
          • drugs associated with vitamin D deficiency
            • phenytoin
            • phenobarbital
            • rifampin
            • cholestyramine
            • cadmium
            • glucocorticoids
          • drugs affecting phosphate homeostasis
            • aluminium-containing phosphate-binding antacid
            • ifosfamide
          • drugs affecting bone mineralization
            • aluminium
            • etidronate
            • fluoride
  • Presentation
    • Symptoms
      • generalized bone and muscle pain
      • fractures of long bones, ribs and vertebrae
      • proximal muscle weakness weakness
      • fatigue
    • Physical exam
      • inspection
        • waddling gait
          • from hip pain and thigh weakness
        • difficulty rising from chair and climbing stairs
  • Imaging
    • Radiographs
      • findings
        • Looser's zones (insufficiency fractures)
          • medial femoral cortex
          • pubic ramus
          • scapula
        • fractures (especially in the proximal femur/femoral neck)
        • biconcave vertebral bodies
        • trefoil pelvis
        • protrusio acetabuli
    • Bone scan
      • findings
        • increased activity
  • Studies
    • Labs
      • Lab values
      • Serum Ca
      • Serum P
      • Alk phos
      • PTH
      • 25-(OH)vit D
      • 1,25-(OH)vit D
      • Urinary Ca
      • Osteomalacia
      • Low
      • Low
      • High
      • High
      • Low
      • Low
      • Low
      • Osteoporosis
      • Normal
      • Normal
      • Variable
      • Normal
      • Normal
      • Normal
      • Normal
      • Tumor induced osteomalacia
      • Low
      • Very low
      • Low
      • Low
      • Low
      • Low
      • Low
      • Osteopetrosis
      • Normal
      • Normal
      • High
      • Normal
      • Normal
      • Normal
      • Normal
  • Histology
    • Characteristic histology includes
      • technique
        • requires transiliac biopsy for definitive diagnosis
      • findings
        • widely separated osteoid seams
  • Treatment
    • Nonoperative
      • large doses of oral vitamin D (1000IU/day), treat underlying cause
        • indications
          • most patients
      • technique
        • specific subgroups of patients
          • on long-term anticonvulsant therapy
            • supplement with 400-800IU/day of vitamin D
          • with hepatobiliary disease
            • supplement with 25(OH)-vit D
          • with renal disease
            • supplement with 1,25(OH)2 vit D
Flashcards (0)
Cards
1 of 0
VIDEOS & PODCASTS (1)
EXPERT COMMENTS (18)
Private Note