Dr.Juan A.Venter Dept. Clinical Imaging Sciences Bloemfontein Academic Hospitals 18/05/2012

1. Dr.JuanA.Venter Dept. Clinical Imaging Sciences Bloemfontein Academic Hospitals 18/05/2012

4. Most common of all metabolic bone disorders • Significant morbidity(50% for hip fractures) and mortality(20% for hip fractures in 1 year) • Treatment cost in Europe : 75 billion Euros by 2050. • Lifetime Osteoporotic Fracture Risk(Caucasian) Woman- 40% Men - 20% • Preventive therapies available.

5. Systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture which usually involves the wrist ,spine, hip, pelvis,ribs or humerus.

10. Detect osteoporosis - (Fragility) fractures • Quantification -Measure bone mass : Semiquantitative(Conventional Radiography) Quantitative (Bone Mass Densitometry) • Morphometry : Radiogrammetry Singh Index Vertebral Morphometry • Bone Mineral Densitometry(BMD) : DXA (Dual energy X – ray absorptiometry) - Axial/Peripheral QCT (Quantitative CT – Axial/Peripheral),HRCT Other – QUS,QMR

11. Increased Radiolucency/Cortical Thinning • Notoriously inaccurate : 30 – 40 % loss of bone mass need to be present before detection • 25 % of apparent osteopenia on radiography (technical faults) or vertebral fractures(juvenile epiphysitis,normalvariants,trauma) have normal BMD • Can detect osteomalacia/hyperparathyroidism • Loss of at least 20% or 4 mm vertebral body height required for diagnosis of vertebral fracture – increase risk of subsequent fractures of vertebrae x 2 and hip x 5

17. Not pain free within 6-8 weeks • Non Anterior Wedge • Posterior Wedge(other than L4+5) • Above T7 • Concave posterior vertebral border is more likely a sign of benign osteoporotic fracture, whereas a convex posterior border suggests malignant disease. Consider : Neoplastic disease – multiple myeloma/metastases Osteomalacia Schauermans disease(Juvenile epiphysistis) Trauma Degeneration MR imaging findings of malignant disease include multiple contrast enhancing lesions or soft-tissue masses, with or without encasing epidural masses and destructive changes

25. Rapid scanning • Precise results if performed meticulously • Extreme low doses of radiation • Vertebral assessement from lateral images obtained on fan beam DXA system can be done at 1/100 th of dose of conventional radiography. • Central/Peripheral DXA

26. Calibrated at least 1/week • Meassurementmonoplanar – g/cm2 and therefor size dependant (children) • All calcium in path of electron beam contributes to BMD(Aortic calcifications degenerative/hyperostotic changes/vertebral wedging,metallic pinning) with overestimation of BMD.Exclude these areas from analysis/Lateral scanning • Strontium ranelate treatment – artefactual increase in BMD • Results of different scanners not interchangeable

27. Need appropriate race and sex matched BMD reference ranges – ethnic differences in BMD and fracture prevelance • Expressed as standard deviation from : Age matched – Z Score Peak bone mass – T Score Normal - > – 1 sd Osteopenia - < -1 > – 2.5 sd Osteoporosis - < -2.5 sd Severe Osteoporosis - < -2.5 sd + 1or > fragility fractures

28. Woman > 65 years and men > 70 years • Radiographic evidence of osteoporotic vertebral fractures or apparent osteopenia • History of fragility fractures after age 40 • Known causes of secondary osteoporosis : Early menopause(< 45 years of age) / hypo gonadism in men/woman Systemic diseases with adverse effect on bone Bone toxic drugs

29. Facilitate desicions regarding initiation/ discontinuation of drug therapy (biphosphonates /HRT) • Strong clinical risk factors: Family history of hip fractures or osteoporosis BMI < 19 kg/m2 Regular C2H5OH intake(>3 drinks/day) Smoking Poor nutrition /Calcium intake/Vitamin D exposure

30. Low specificity – < 50 % of known osteoporotic fractures have BMD in osteoporotic range(T < - 2.5) • Other risk factors like propensity to falls or qualitative risk factors like bone turnover not included • Extrapolation to other populations measured at different skeletal sites with other techniques (QUS,QCT) not acceptable. • Other metabolic bone diseases • Intervention threshold applicable to all

31. NOFSA guidelines for diagnosis of osteoporosis • Confirm diagnosis with BMD or presence of fragility fracture before initiation of treatment with bone active drugs. • Axial BMD to be used to diagnose and access rate of bone loss/gain. QCT/QUS not recommended and results cannot be applied to T score based WHO diagnostic classification • Lowest BMD value measured at spine,total femur and femur neck(or distal radius if invalid) • Express results for post menopausal Caucasian woman as T scores and Z scores for pre menopausal woman and men < 50 year • Men over 50 years : Employ female reference data to determine T score • Local black population : use reference data for Caucasian females for all subjects of all races until local reference values become available.

32. NOFSA guidelines for diagnosis of osteoporosis • Children:Low BMD + significant fracture history • Follow up scans every 18-24 months or earlier in GIOP • Search for evidence of vertebral compression fractures in all who qualify for BMD measurement – Standard x-ray and use modified Genantsemiquintative system to grade (Gr.1-3) Higher grade = higher risk for subsequent fractures of hip and vertebrae or DXA VFA .

33. Considered treatment after prior fragility fracture(wrist, spine,hip ,pelvis ,rib ,humerus) regardles of BMD value • Considered treatment if DXA T Score < -2.5 at hip or spine • Considered treatment if DXA T score -1- -2.5 (osteopenia) if significant clinical risk factors. • BMD measured on all patients on long term glucocorticosteroids(50% develop GIOP regardless of dose)-start treatment if T Score < - 1.5 • Biphophonates – 1st line preventative therapy and anabolics reserved for advanced disease

35. Reduce the high subjectivity and poor reproducibility of qualitative readings • Vertebral fractures are one of the most important CRF – 60% asymptomatic and go undetected if not routinely searched for • Visualize lateral spine on DXA with VFA software • Lower radiation dose and cost compared to conventional radiography • Conventional radiography remain gold standard – often only requested if fracture is suspected

37. Separate estimation of cortical and trabecular bone • True volumetric density – g/cm3 making it non size dependant(children/small stature) • Performed with calibration reference phantom to transform HU into BMD equivalents • Radiation dose compares favourably with conventional radiography • Excellent for predicting vertebral fractures and serially measuring bone loss - selectively assesses the metabolically active and structurally trabecular bone • Increase in marrow fat is age related, single-energy CT data can be corrected with use of age-related reference databases

39. Can be used to detect differences in trabecular structure depending on patient age, BMD, and osteoporotic status • Most often performed at peripheral sites such as the calcaneus, knee, and wrist. • Substantial improvement in fracture discrimination made possible by considering structural information as well as BMD • May replace biopsy when this would be advocated.

43. Osteomalacia – Looser Zone

44. Osteomalacia – Looser Zone

46. Rickets

47. Rickets

48. Rickets

49. Rickets

50. http://www.iofbonehealth.org/ - accessed 28/04/2012 • Grainger and Allison’s Diagnostic Radiology A Textbook of Medical Imaging,5th Edition • Orthopedic Imaging A Practical Approach Adam Greenspan,5th Edition • Radiographics : September – October 2011 Integrated Imaging Approach to Osteoporosis: State-of-the-Art Review and Update