Lecture 5 - Ageing Bones Overview 2024 PDF

Ms Kezia Brown Senior clinical lecturer Consultant orthopaedic surgeon Body in Motion MBChB The ageing skeleton  MBChB...

Ms Kezia Brown Senior clinical lecturer Consultant orthopaedic surgeon Body in Motion MBChB The ageing skeleton  MBChB Body in Motion Metabolic Bone Diseases Ageing bones Disorders of Bone Remodelling Osteoporosis: Disorders resorption > formation of Mineralisation Paget’s disease: resorption and formation increased Osteopetrosis: resorption decreased  MBChB Body in Motion Osteoporosis Ageing bones Osteoporosis is disorder of bone quantity, not quality Skeletal disorder with: Deterioration of microarchitecture Compromised bone strength Increased risk of fractures Back to this later…  MBChB Body in Motion Paget’s Disease of Bone Ageing bones Abnormal localised bone remodelling Primarily increased OC resorption Increased but disorganised bone formation 2nd most common MBD  MBChB Body in Motion Paget’s Disease of Bone Ageing bones Abnormal localised bone remodelling Primarily increased OC resorption Increased but disorganised bone formation 2nd most common MBD Clinical features Enlarged skull Bowing of long bones Large joint OA Fractures Nerve compression Deafness Polyostotic disease  MBChB Body in Motion Paget’s Disease of Bone Ageing bones Paget’s sarcoma Malignant change Less than 1% of Paget’s cases Most commonly osteosarcoma Osteo = osteoblastic differentiation and malignant osteoid production Sarcoma = malignancy from mesenchymal cells Metastatic disease has poor prognosis Case courtesy of Radswiki, Radiopaedia.org, rID: 11727  MBChB Body in Motion Paget’s Disease of Bone Ageing bones Most cases are spontaneous but significant genetic component ?environmental insult in genetically susceptible individual Pathology Abnormal osteoclasts/precursors Greater in number, unusually large and hypersensitive to stimulation 3 phases which can co-exist in the same bone Lytic – Intense osteoclastic resorption Mixed – resorption and compensatory formation Sclerotic – predominant osteoblastic formation Pathologic basis of disease, Robbins & Cotran  MBChB Body in Motion Paget’s Disease of Bone Ageing bones Investigation Imaging Radiographs Bone scan Lab results Elevated ALP (marker of bone turnover) Histology Treatment OC inhibition Arthroplasty  MBChB Body in Motion Osteopetrosis Ageing bones Defective osteoclastic resorption Cannot acidify Howship’s lacuna Bone formed but not remodelled Abnormal bone Dense Obliterated medullary canal Predisposition to fracture Low energy Transverse Increased risk of non/mal-union Case courtesy Case courtesy of Dr Zeeshan of Dr Maulik GhiasSKhan, Patel,Radiopaedia.org, Radiopaedia.org,rID rID61470 9142  MBChB Body in Motion Metabolic Bone Diseases Ageing bones Disorders of Bone Remodelling Osteoporosis: resorption > formation Paget’s disease: resorption and formation increased Osteopetrosis: resorption decreased Disorders of Mineralisation Hyperparathyroidism Vitamin D-related disorders (osteomalacia, rickets)  MBChB Body in Motion Hyperparathyroidism Ageing bones Increase in circulating levels of PTH as a result of excess production by one or more parathyroid glands Primary hyperparathyroidism Intrinsic abnormality of the parathyroid gland(s) Pathological increase in PTH production Parathyroid adenoma 85% Secondary hyperparathyroidism Increased PTH secretion from hypertrophic parathyroid glands Secondary to chronic hypocalcaemia/hyperphosphataemia Vit D deficiency Chronic renal disease  MBChB Body in Motion Main effects of PTH Ageing bones Increases bone resorption OBs release more RANKL and less OPG OCs differentiate and activate Increased renal hydroxylation of Vit D Active form of Vit D (calcitriol) Increased RANKL release Increase intestinal uptake Increase renal uptake  MBChB Body in Motion Main effects of PTH Ageing bones Increases bone resorption OBs release more RANKL and less OPG OCs differentiate and activate Increased renal hydroxylation of Vit D Active form of Vit D (calcitriol) Increased RANKL release Increase intestinal uptake Increase renal uptake  MBChB Body in Motion Hyperparathyroidism Ageing bones Symptoms and signs ‘Bones, stones, abdominal groans. Thrones and psychic moans’ Arthritis, osteoporosis Kidney stones Constipation, GI ulcers, acute pancreatitis Polyuria Depression, forgetfulness, ‘TATT’ https://www.niddk.nih.gov/  MBChB Body in Motion Hyperparathyroidism Ageing bones Symptoms and signs ‘Bones, stones, abdominal groans. Thrones and psychic moans’ Arthritis, osteoporosis Kidney stones Constipation, GI ulcers, acute pancreatitis Polyuria Depression, forgetfulness, ‘TATT’ https://www.niddk.nih.gov/  MBChB Body in Motion Hyperparathyroidism Ageing bones Symptoms and signs ‘Bones, stones, abdominal groans. Thrones and psychic moans’ Arthritis, osteoporosis Kidney stones Constipation, GI ulcers, acute pancreatitis Polyuria Depression, forgetfulness, ‘TATT’ https://www.niddk.nih.gov/  MBChB Body in Motion Hyperparathyroidism Ageing bones Symptoms and signs ‘Bones, stones, abdominal groans. Thrones and psychic moans’ Arthritis, osteoporosis Kidney stones Constipation, GI ulcers, acute pancreatitis Polyuria Depression, forgetfulness, ‘TATT’ https://www.niddk.nih.gov/  MBChB Body in Motion Hyperparathyroidism Ageing bones Primary Parathyroidectomy = 97% cure Secondary Underlying cause Vit D deficiency most common Renal disease complex  MBChB Body in Motion Hyperparathyroidism Ageing bones Primary Parathyroidectomy = 97% cure Secondary Underlying cause Vit D deficiency most common Renal disease complex  MBChB Body in Motion Vitamin D Ageing bones Source from sunlight or diet 2 hydroxylations Liver -> 25 hydroxy vitamin D Kidneys -> 1,25 dihydroxy vitamin D Calcitriol (active form) Receptors throughout the body Increase availability of calcium Also maintains serum phosphate Decrease PTH synthesis Increases FGF23 (feedback loop)  MBChB Body in Motion Rickets Ageing bones Defects in mineralisation caused by inadequate calcium and phosphate prior to physeal closure Reduced mineralisation at ZoPC in physes Congenital – Familial hypophosphataemic Inability of kidneys to absorb phosphate Acquired – Vitamin D deficient Lack of dietary Vit D intake or sunlight exposure Low Vit D levels lead to decreased calcium absorption Low Ca -> Increase PTH -> Bone resorption  MBChB Body in Motion Rickets Ageing bones Orthopaedic manifestations Brittle bones with physeal cupping/widening Bowing of long bones Muscle hypotonia and weakness Flattening of skull Enlargement of costal cartilage Kyphosis (cat back) Other manifestations Dental abnormalities Irritability, listlessness  MBChB Body in Motion Rickets Ageing bones Vit D deficient Vit D Calcium Hypophosphataemic Calcitriol Phosphate (controversial) Surgery to correct deformity  MBChB Body in Motion Osteomalacia Ageing bones Defects in mineralisation caused by inadequate calcium and phosphate AFTER physeal closure Rickets and osteomalacia are manifestations of the same pathological process Qualitative defect of bone, rather than quantitative defect like osteoporosis Causes Diet Drugs that cause Malabsorption (eg coeliac disease) Vit D deficiency Renal osteodystrophy Phosphate homeostasis disruption Alcoholism Altered bone mineralisation Tumour  MBChB Body in Motion Osteomalacia Ageing bones Bone and muscle pain Atypical fractures ‘Looser zones’ Femur/femoral neck fractures Proximal muscle weakness Fatigue Hip arthritis with ‘protrusio’  MBChB Body in Motion Osteomalacia Ageing bones Bone and muscle pain Atypical fractures ‘Looser zones’ Femur/femoral neck fractures Proximal muscle weakness Fatigue Hip arthritis with ‘protrusio’  MBChB Body in Motion Osteomalacia Ageing bones Bone and muscle pain Atypical fractures ‘Looser zones’ Femur/femoral neck fractures Proximal muscle weakness Fatigue Hip arthritis with ‘protrusio’ Treatment = Large doses of vitamin D  MBChB Body in Motion Ageing bones Osteoporosis and fractures  MBChB Body in Motion Osteoporosis Ageing bones Osteoporosis is disorder of bone quantity, not quality  MBChB Body in Motion Osteoporosis Ageing bones Osteoporosis is disorder of bone quantity, not quality  MBChB Body in Motion Osteoporosis Ageing bones Osteoporosis is disorder of bone quantity, not quality  MBChB Body in Motion Osteoporosis Ageing bones Osteoporosis is disorder of bone quantity, not quality  MBChB Body in Motion Osteoporosis Ageing bones Osteoporosis is disorder of bone quantity, not quality Skeletal disorder with: Deterioration of microarchitecture Compromised bone strength Increased risk of fractures  MBChB Body in Motion Mechanism of injury Ageing bones Falls < 2m – 59 % Falls > 2m – 11 % RTA – 15% Assault – 5% Other – 10%  MBChB Body in Motion Epidemiology Ageing bones General trend Young male Older female Bimodal distribution Peak 1 Young males High energy n/105 Assault, falls >2m, RTC Peak 2 Older females Low energy Falls 55 females >70 males Bone density n/105 Post-menopause Age-related Secondary causes Disease Drugs Smoking/alcohol Age  MBChB Body in Motion Bone mass Ageing bones  MBChB Body in Motion Peak bone mass Ageing bones PBM  MBChB Body in Motion Peak bone mass Ageing bones  MBChB Body in Motion Bone mass Ageing bones  MBChB Body in Motion Bone mass Ageing bones  MBChB Body in Motion Oestrogen and bone Ageing bones RANK-L Osteoblasts Osteoclasts  MBChB Body in Motion Oestrogen and bone Ageing bones RANK-L RANK-L RANK-L Oestrogen Osteoblasts Osteoclasts  MBChB Body in Motion Oestrogen and bone Ageing bones RANK-L RANK-L RANK-L RANK-L RANK-L RANK-L Osteoblasts Osteoclasts  MBChB Body in Motion Bone mass Ageing bones  MBChB Body in Motion Fracture threshold Ageing bones  MBChB Body in Motion Fracture threshold Ageing bones  MBChB Body in Motion Fracture threshold Ageing bones  MBChB Body in Motion Terminology Ageing bones Insufficiency fractures Type of stress fracture Cumulative result of repeated normal loading of abnormal bone Different from fatigue fracture (normal bone with repeat abnormal stresses) Fragility fracture Result of forces that would not fracture normal bone Almost always osteoporotic  MBChB Body in Motion Spine Ageing bones Vertebral wedge compression fractures Very common Insufficiency or low energy trauma Often affects multiple levels  MBChB Body in Motion Spine Ageing bones Vertebral wedge compression fractures Very common Insufficiency or low energy trauma Often affects multiple levels Progressive deformity Height loss Reduced pulmonary volume Protruding abdomen Distension, constipation, early satiety  MBChB Body in Motion Spine Ageing bones Vertebral wedge compression fractures Very common Insufficiency or low energy trauma Can’t see feet Can’t look forward CoB shifted forwards Often affects multiple levels Progressive deformity  MBChB Body in Motion Proximal humerus Ageing bones Caused by simple fall 3rd most common appendicular # 2:1 female to male ratio More complex with age Most treated in sling Traction by weight of arm Early rehab Surgery if more complex Outcomes variable  MBChB Body in Motion Proximal humerus Ageing bones Caused by simple fall 3rd most common appendicular # 2:1 female to male ratio More complex with age Most treated in sling Traction by weight of arm Early rehab Surgery if more complex Outcomes variable  MBChB Body in Motion Wrist fractures Ageing bones Most common MSK injury 17.5% of all fractures Thumb 3:1 female:male Anterior Eponymous terms Smith’s = volar extra-articular Colles’ = dorsal extra-articular Volar Dorsal  MBChB Body in Motion Wrist fractures Ageing bones Displaced fracture of the distal radius It is… – Dorsally angulated – Dorsally translated – Shortened – Extra-articular – Colle’s Fracture  MBChB Body in Motion Wrist fractures Ageing bones Displaced fracture of the distal radius It is… – Dorsally angulated – Dorsally translated – Shortened – Extra-articular – Colle’s Fracture  MBChB Body in Motion Wrist fractures Ageing bones Displaced fracture of the distal radius It is… – Dorsally angulated – Dorsally translated – Shortened – Extra-articular – Colle’s Fracture  MBChB Body in Motion Wrist fractures Ageing bones Displaced fracture of the distal radius It is… – Dorsally angulated – Dorsally translated – Shortened – Extra-articular – Colle’s Fracture  MBChB Body in Motion Wrist fractures - management Ageing bones Outcomes Usually very good if adequate rehab Residual stiffness quite common Complex regional pain syndrome Risk factor for future fracture Most >55 need DEXA scan  MBChB Body in Motion Pelvic fractures Ageing bones Pubic rami Fall backwards from standing Land on buttocks Usually both sup/inf Conservative management  MBChB Body in Motion Pelvic fractures Ageing bones Pubic rami Fall backwards from standing Land on buttocks Usually both sup/inf Conservative management  MBChB Body in Motion Hip fractures Ageing bones Extremely common with increasing incidence Very high morbidity/mortality 1/3 will return to previous function 1/3 will loose independence 1/3 will die within a year Require early surgery with MDT input for best chance of recovery  MBChB Body in Motion Hip fractures Ageing bones The patient Reason for the fall Co-morbidities Mental state Risk of further fractures and falls The bone Osteoporosis Surgery to fix or replace the hip and allow immediate mobilisation  MBChB Body in Motion Hip fractures - management Ageing bones Historically was bedrest Outcomes Muscle wasting Loss of mobility Bed sores Pneumonia Pulmonary embolism Death All hip fractures treated with surgery now (almost)  MBChB Body in Motion Hip fractures - management Ageing bones  MBChB Body in Motion Hip fractures - intracapsular Ageing bones Intracapsular # In situ fixation Arthroplasty  MBChB Body in Motion Hip fractures - intracapsular Ageing bones Displaced intracapsular Hemi-arthroplasty  MBChB Body in Motion Hip fractures - management Ageing bones Intracapsular Bin it or pin it Undisplaced = Fix Cannulated hip screws Displaced = Replace Hemiarthroplasty if low demand, dementia Total hip arthroplasty if active, cognitively intact, high functional demands  MBChB Body in Motion Hip fractures - extracapsular Ageing bones Intertrochanteric Sliding hip screw  MBChB Body in Motion Hip fractures - management Ageing bones Intracapsular Extracapsular Bin it or pin it Intertrochanteric Undisplaced = Fix Sliding hip screw Cannulated hip screws Subtrochanteric Displaced = Replace Intramedullary nail Hemiarthroplasty if low demand, dementia Total hip arthroplasty if active, cognitively intact, high functional demands  MBChB Body in Motion Atypical femoral fractures Ageing bones Bisphosphonates Insufficiency fracture No trauma Pattern Subtrochanteric Lateral cortex Transverse Cortical ‘beaking’ Osteoclast remodelling inhibited Unable to heal micro-trauma Aim to prevent complete fracture  MBChB Body in Motion Life after fracture Ageing bones Very high morbidity/mortality 1/3 will return to previous function 1/3 will loose independence 1/3 will die within a year 1 year mortality worse than many cancers Palliative care? Hip fracture is a symptom of general decline