Bone pain Flashcards
What is osteomalacia?
Osteomalacia describes softening of the bones secondary to low vitamin D levels that lead to decreased bone mineral content. If this occurs in growing children, it is referred to as rickets, with the term osteomalacia preferred for adults.
What are the causes of osteomalacia?
Causes include vitamin D deficiency, malabsorption, lack of sunlight, diet, chronic kidney disease, drug-induced (e.g., anticonvulsants), inherited (hypophosphatemic rickets), liver disease (e.g., cirrhosis), and coeliac disease.
What are the features of osteomalacia?
Features include bone pain, bone/muscle tenderness, fractures (especially femoral neck), and proximal myopathy which may lead to a waddling gait.
What investigations are used for osteomalacia?
Investigations include blood tests showing low vitamin D levels, low calcium and phosphate (in around 30%), raised alkaline phosphatase (in 95-100% of patients), and x-ray showing translucent bands (Looser’s zones or pseudofractures).
What is the treatment for osteomalacia?
Treatment includes vitamin D supplementation, often starting with a loading dose, and calcium supplementation if dietary calcium is inadequate.
What is Paget’s disease of the bone?
A disease of increased but uncontrolled bone turnover
It is thought to be primarily a disorder of osteoclasts, with excessive osteoclastic resorption followed by increased osteoblastic activity.
What is the UK prevalence of Paget’s disease?
5%
Symptomatic in only 1 in 20 patients.
Which bones are most commonly affected by Paget’s disease?
- Skull
- Spine
- Pelvis
- Long bones of the lower extremities
These areas are typically where the disease manifests.
List the predisposing factors for Paget’s disease.
- Increasing age
- Male sex
- Northern latitude
- Family history
These factors increase the likelihood of developing the disease.
What percentage of patients with Paget’s disease are symptomatic?
5%
This means that the majority of patients do not exhibit symptoms.
What is the stereotypical presentation of a patient with Paget’s disease?
An older male with bone pain and an isolated raised ALP
Bone pain may occur in areas such as the pelvis, lumbar spine, or femur.
What classical features may be seen in untreated Paget’s disease?
- Bowing of tibia
- Bossing of skull
These are characteristic deformities that can develop over time.
What blood test results are typically seen in Paget’s disease?
- Raised alkaline phosphatase (ALP)
- Calcium and phosphate typically normal
- Hypercalcaemia may occur with prolonged immobilisation
Other markers of bone turnover include procollagen type I N-terminal propeptide (PINP), serum C-telopeptide (CTx), urinary N-telopeptide (NTx), and urinary hydroxyproline.
What x-ray findings are associated with Paget’s disease?
- Osteolysis in early disease
- Mixed lytic/sclerotic lesions later
- Skull x-ray shows thickened vault and osteoporosis circumscripta
These findings help in diagnosing the disease.
What does bone scintigraphy show in Paget’s disease?
Increased uptake at the sites of active bone lesions
This imaging technique helps to identify areas of active disease.
List the indications for treatment in Paget’s disease.
- Bone pain
- Skull or long bone deformity
- Fracture
- Periarticular Paget’s
These conditions warrant therapeutic intervention.
What are the common treatment options for Paget’s disease?
- Bisphosphonate (oral risedronate or IV zoledronate)
- Calcitonin (less commonly used)
Bisphosphonates are the mainstay of treatment.
What complications can arise from Paget’s disease?
- Deafness (cranial nerve entrapment)
- Bone sarcoma (1% if affected for > 10 years)
- Fractures
- Skull thickening
- High-output cardiac failure
These complications can significantly affect the patient’s quality of life.
What is primary hyperparathyroidism caused by?
Excess secretion of PTH resulting in hypercalcaemia
What is the most common cause of hypercalcaemia in outpatients?
Primary hyperparathyroidism
What percentage of primary hyperparathyroidism cases is due to a parathyroid adenoma?
85%
List the causes of primary hyperparathyroidism by percentage.
- 85%: solitary adenoma
- 10%: hyperplasia
- 4%: multiple adenoma
- 1%: carcinoma
What percentage of patients with primary hyperparathyroidism are asymptomatic?
Around 80%
What mnemonic can be used to remember the symptomatic features of primary hyperparathyroidism?
‘bones, stones, abdominal groans and psychic moans’
