OR7.1 | Metabolic Bone Disease Assessment — Summary & Reflection

KEY TAKEAWAYS

Metabolic bone diseases share the anatomical substrate of disordered bone but differ fundamentally in mechanism, age of onset, biochemical fingerprint, and treatment strategy. Osteoporosis is a disease of bone mass reduction with intact mineralisation — diagnosed by DEXA T-score at or below -2.5 or by fragility fracture; biochemistry is normal; treated with bisphosphonates, calcium/vitamin D supplementation, and fall prevention. Osteomalacia (adult) and rickets (child) both represent defective mineralisation of osteoid/cartilage due predominantly to vitamin D deficiency — characterised by the triad of low calcium, low phosphate, and elevated ALP, with elevated PTH and low vitamin D; Looser's zones are pathognomonic in adults; rickets produces widened metaphyses, rachitic rosary, genu varum/valgum, and frontal bossing in children; treatment is vitamin D and calcium replacement, with deformity correction only after metabolic control is confirmed. Paget's disease is focal disorganised remodelling — normal calcium and phosphate but markedly elevated ALP; cotton-wool skull, bowing of femur/tibia, picture-frame vertebra, and hearing loss are typical; complications include high-output cardiac failure, nerve compression, and sarcomatous transformation; treated with zoledronic acid. The biochemical fingerprint — calcium, phosphate, ALP, PTH, vitamin D — is the fastest route to correct diagnosis.

REFLECT

Take a moment to consider what you have learned today through the lens of your own clinical encounters. India's vitamin D deficiency epidemic means that virtually every patient cohort — urban and rural, paediatric and geriatric — carries hidden metabolic bone disease. Think about a patient you have seen (or can imagine seeing) in your college clinic or on a ward round: an elderly woman with a recent fall and wrist fracture; a toddler with bowed legs from a periurban slum; a middle-aged man with hat trouble and a dramatically high ALP on a routine blood test. How would you now approach their biochemical workup differently? Which finding would you anchor to first — the ALP, the calcium, the phosphate? And consider the healthcare equity dimension: rickets and osteomalacia are preventable diseases. What systemic interventions — vitamin D supplementation programmes, food fortification, sun exposure education — could reduce their incidence at a population level? As a future orthopaedic surgeon or physician, your ability to diagnose and treat the metabolic cause, not just the skeletal deformity, will determine whether your patients achieve lasting cure or face recurrent disease.