Category Archives: Rheumatology and bone disease

Other hereditary diseases

Osteopetrosis (marble bone disease) This condition may be inherited in either an autosomal dominant or an autosomal recessive manner; the recessive type is severe and the dominant type is mild. In the severe form, bone density is increased throughout the skeleton but bones tend to fracture easily. Involvement of the bone marrow leads to a leucoerythroblastic anaemia. There is mental retardation and early deat

Connective tissue

All connective tissues have a large proportion of extracellular matrix as well as cells. This matrix consists of extracellular macromolecules containing collagens, elastins, non-collagenous glycoproteins and proteoglycans. Collagens These consist of three polypeptide chains (a chains) wound around one another in a triple helical confirmation. These a chains contain repeating sequences of Gly-X-Y triplets wher

Neoplastic bone disease

Malignant tumours of bone are shown. The most common tumours are metastases from the bronchus, breast and prostate. Metastases from kidney and thyroid are less common. Symptoms are usually related to the anatomical position of the tumour, with local bone pain over the area. Systemic symptoms including malaise and pyrexia, and aches and pains occur and are some times related to the hypercalcaemia . The diagn

Infections of bone

Osteomyelitis Staphylococcus is the organism responsible for 90% of cases of acute osteomyelitis . Other organisms include Haemophilus influenzae and Salmonella; infection with the latter may occur as a complication of sickle cell anaemia. Osteomyelitis can be due either to metastatic haem atogenous spread (e.g. from a boil) or to local infection. Malnutrition, debilitating disease and decreased immunity may

Calcium disorders

Hypocalcaemia and hypoparathyroidism PATHOPHYSIOLOGY Hypocalcaemia may be due to deficiencies of calcium homeostatic mechanisms, secondary to high phosphate levels or other causes of hypocalcaemia. Hypoparathyroidism is uncommon. Paget’s disease CAUSES 1 Renal failure is the commonest cause of hypocalcaemia. 2 Immediately following thyroidectomy and parathyroidectomy, hypocalcaemia is usually transient.


EPIDEMIOLOGY Osteoporosis means thin bone and the term implies a reduction in bone mass including all components of bone and not just calcium. It is already a major problem; it is said that 40% of Caucasian women and 20% of men will suffer fractures as a result of osteoporosis. The risk in women will triple as a result of increasing life expectancy. One-third of women will have had a fracture by the age of 9

Metabolic bone disease

Osteomalacia Pathophysiology This results from inadequate mineralization of the osteoid framework, leading to soft bones. It is thus usually caused by a defect in vitamin 0 availability or metabolism. The effect on bone is shown. CAUSES DEFICIENCY OF VITAMIN D • Dietary plus inadequate sunlight exposure often seen in Asian immigrant females in Western countries. increased melanin in skin decreases vitamin 0

Physiology, structure and formation of bone

Bone is subdivided into cortical and cancellous bone. In an adult long bone, cortical bone forms the diaphyseal shaft within which is the medullary cavity containing bone marrow. Cancellous bone consists of a network of interconnecting trabecular plates and rods, and is found within the medullary cavity at the epiphyses. Bone remodelling takes place at four bone surfaces: the periosteum, the Haversian system


INTRODUCTION Bone forms 25% of the weight of a normal adult; its major mineral constituents are calcium, phosphate and, to a much lesser extent, magnesium. While obviously there is major growth in childhood, bone is not a static framework in the adult. There is a continuous process of bone remodelling with bone formation by osteoblasts and resorption by osteoclasts. While exchange of calcium between bone and

Soft-tissue rheumatism

Soft-tissue rheumatism is a convenient term for a number of conditions with similar features . They cause musculoskeletal or joint pain that arises, not from the joint itself, but from surrounding structures such as the tendon sheaths and bursae. These conditions are benign and in most cases self-limiting. They are often regarded as trivial except by those who have them. Many are best treated by local cortic