The recognition and reporting of vertebral fractures: a powerful tool to reduce the risk of future osteoporotic fractures B Lentle, J Brown, A Khan, Leslie WD, Levesque J, Lyons DJ, Siminoski K, Tarulli G Osteoporosis Canada
Vertebral fracture prevalence: 60 50 40 30 Number 20 10 0 T4 T6 T8 T10 T12 L2 L4
Mortality/1000 Person-years Mortality rates by number of 40 35 30 25 20 15 10 5 0 vertebral fractures: p for trend < 0.001 0 1 2 3 4 5+ Number of Vertebral Fractures Kado D. Arch Intern Med 1999; 159: 1215
Vertebral fractures predict hip fracture: 4 RR = Prevalent Vertebral Fractures No Prevalent Fracture 3.8 Relative Risk 3.5 3 2.5 2 1.5 2.3 2.4 2.8 1 Melton '99 Gunnes '98 Black '99 Lauritzen '93
Survival Rates after Fracture: Survival % 100 80 60 40 20 0 100 80 60 40 20 0 100 80 60 40 20 0 Vertebral Observed Expected Hip Distal forearm 0 1 2 3 4 5 Years after Fracture Cooper C. Am J Epidemiol 1993; 137: 1001
Mean # of Days 180 160 140 120 100 80 60 40 20 0 All vertebral fractures are clinically important: Days of pain, or bed rest due to pain, over 3 years No Incident Fracture Severe Back Pain Radiographic Fracture Clinical Fracture Mean # of Days 45 40 35 30 25 20 15 10 Nevitt M. Arch Intern Med 2000; 160: 77 5 0 No Incident Fracture Bed Rest Radiographic Fracture Clinical Fracture
Radiological fracture recognition (1): Review of chest radiographs on 934 women aged >60 years, admitted to hospital On review 132 had 1 or more spinal fractures Of these: 65 (49%) were reported 23 (17%) were noted in the medical record 25 (19%) were treated Gehlbach SH et al. Osteoporosis Int 2000;11:577-582
Radiological fracture recognition (2): In a Canadian study of emergency room radiography the following were the chief findings in relation to the thoracic spine: Mean age of the population was 75 years, 47% were women, and 46% were admitted to the hospital. According to the reference radiologist, prevalence of moderate to severe vertebral fractures was 22%. Simple agreement was about 88% among reviewers; kappa values were moderate (0.56-0.58). Only 55% (12/22) of the vertebral fractures identified were mentioned in the radiology reports. Kim N, Rowe BH, Raymond G, Jen H, Colman I, Jackson SA et al. Underreporting of vertebral fractures on routine chest radiography. Am J Roentgenol. 2004;182:297-300.
Role of CT & MRI CT = Clarify radiographic findings MRI = Useful for recognizing fracture acuity and incidental disease (e.g. tumours)
Osteoporotic fracturing the pathological view:
Risk prediction and prevalent fractures: Ross PD et al. Pre existing fractures and bone mass predict vertebral fracture incidence in women. Ann Intern Med 1991; 114: 919 923.
Vertebral body fractures as a special case: Vertebral fractures may occur incrementally and not catastrophically Mechanism of injury: axial cf. transverse loading (crush) Vertebral fractures may be associated with a vaccuum phenomenon Vertebral fractures may only be evident under load-bearing The definition of vertebral fractures is subject to debate (and varies by practitioner and country)
Vertebral deformities: All fractures cause deformities Not all deformities are due to fracturing
Spinal fracturing: Low trauma spinal fractures: 60% are asymptomatic Hajcsar EE, Hawker G, Bogoch ER. Investigation and treatment of osteoporosis in patients with fragility fractures. Canad Med Ass J 2000; 163: 819-822.
Spinal osteoporosis: 1. Spinal deformities (fractures) 2. Prominent vertical trabeculae (loss of secondary trabeculation)
Genant Grading: Vertebral fracture assessment using a semiquantitative technique Crush Biconcavity Normal (Grading 0) Wedge Gd. 1: <25 % deformity Gd. 2 25 40 % deformity Gd. 3: >40 % deformity Genant HK et al. J Bone Miner Res. 1993; 8: 1137-1148
Problematical aspects of the Genant paradigm: It proposes a quantitative classification It makes unrealistic distinctions between fracture types Morphometry cf. radiological signs of fracture Both projected area ( volume ) and vertical dimensions are invoked The reference dimensions are subject to variation and interpretation The grades overlap Grade 1: 20 25% Grade 2: 25 40% Grade 3: > 40% The classification has suffered mutation or creep
Spinal morphometry:
Osteoporotic fractures are nearly always end-plate fractures: Jiang G, Eastell R, Barrington NA, Ferrar L. Comparison of methods for the visual identification of prevalent vertebral fracture in osteoporosis. Osteoporos Int 2004; 15: 887-896
Grade 1 anterior wedge and crush (superior end plate) fracture:
A Grade 2 anterior wedge and superior end-plate fracture:
A Grade 2 anterior wedge and end-plate fracture:
A Grade 3 crush (superior end plate) fracture (arrow)
Glucocorticoid-induced osteoporosis: These fractures induce sub-cortical schlorisis
Tc-99m MDP bone scan: Low trauma fractures of the sacrum, sacral ala and coccyx are best recognized by radionuclear bone scans
Differential diagnosis:
The lower pole of scapula (larger arrow) projected over T 7:
Congenital abnormalities:
Orthogonal views of the lower thoracic spine in a patient with a T 10 butterfly (bifid) vertebra:
Cupid s bow ( notochordal ) defects (L3-5): Dietz GW, Christenson EE.; Vertebrae 1976; 121: 577-579; Chan KK, Sartoris DJ, Haghighi P, Sledge P, et al.; Radiology 1997; 202: 253-256
Acquired abnormalities:
Scheuermann disease Juvenile disc disease
Scheuermann disease mimics: Hereditary progressive arthro-ophthalmopathy (Stickler syndrome) Acrodysostosis (peripheral dysostosis)
Intervertebral Disc Herniation
Schmorl s nodes and limbus defects: Disc herniation into the vertebral body (Schmorl node) Disc herniation through the secondary ring ossification centre (limbus defect)
Schmorl s nodes:
Spectrum of Intervertebral Disc Herniation
A limbus defect at the antero-superior margin of L3.
Secondary ossification centres: Lumbar spine 5-year old
Disc disease and vertebral remodelling:
Summary: The old: About ten systems varying between subjective and objective; quantitative and qualitative Summarised in: Genant H et al. Monograph on vertebral fractures Eastell et al: two grades, JBMR, 1991 The new: Jiang G. et al. Prevalence SQ (24%) > Qual (11%) > ABQ (7%); BMD α Qual/ABQ OI 2004 Increasingly, European studies (ISCD) focus on end-plate changes
Inter-observer variability: semiquantitative visual assessment of prevalent fractures 100 90 80 70 60 50 40 30 20 10 0 First reading (%) Second reading (%) % Agree Experienced obs. Inexperienced obs.
Incident fracturing: Brian C Lentle, MD, FRCPC; Jacques P Brown, MD, FRCPC; Aliya Khan, MD, FRCPC; William D Leslie, MD, FRCPC; Jacques Levesques, MD, FRCPC; David J Lyons, MD, FRCPC; Kerry Siminoski, MD, FRCPC; Giuseppe Tarulli, MD, FRCPC; Robert G Josse, MD, MBBS, FRCPC; Anthony Hodsman, MD, FRCPC; CARJ Vol 58, No 1, February 2007; 27-36