Introduction 1 2 3 4 4 6 5 6 7 8 9 11 9 Given that vertebral fracture is a significant risk factor for further fracture, and that vertebral fractures often go undiagnosed, this study set out to determine the proportion of patients attending a Fracture Liaison Service following a non-vertebral fracture who also have an unrecognised vertebral fracture. 12 13 12 14 Methods 3 3 17 Statistical analysis Sex: male/female Age: 50–64, 65–74, 75+ 2 2 T-score: ≥−1, −2.4 to −1.1, ≤−2.5 Prior fracture history: yes/no t Results Data was collected during the routine work of the FLS between September 2004 and March 2005. The data was analysed between July 2005 and July 2006. Demographics n 2 n 2 n 2 n 2 n 2 n n n 1 n n n n n n Fig. 1 Presenting fracture and prevalence of vertebral deformity for each type of fracture. *Other includes olecranon, patella, scapula, sternum and shaft of femur  n n n n Information regarding risk factors for fracture—including prior history of fracture, early menopause, BMI, history of smoking or excess alcohol, thyrotoxicosis, history of maternal hip fracture, family history of osteoporosis, steroid use, rheumatoid disease, history of recurrent falls and partial gastrectomy—was also collected. Of all patients, 63% had one fracture risk factor, 23% had two risk factors, 11% had three risk factors and 3% had more than three risk factors. Risk fractures for fracture were assessed after patients had presented to the FLS with a non-vertebral fracture; therefore, every patient had a prior history of fracture. Vertebral deformity consistent with fracture 1 p 2 Fig. 2 Presenting fracture and prevalence of multiple (two or more) vertebral deformities  Of the patients with vertebral deformities, 3 (3.6%) had unreadable scans for grading. Of the 80 remaining patients, 58 (72.5%) had Grade 2 or Grade 3 deformities. Thirty-two (55.2%) of the patients with vertebral deformity of Grade 2 and Grade 3 had multiple vertebral fractures. Of the sub-group of patients with vertebral deformity of Grade 2 and 3, 56.9% had deformities in the thoracic spine, 22.4% in the lumbar spine and 20.7% in both regions. There was no significant difference between the vertebral deformity population and the sub-population of patients with Grade 2 or 3 deformities, in terms of the proportion of patients with multiple vertebral deformities or in the site of deformity. 1 p p Table 1 Impact of lumbar spine T-score on prevalence of vertebral deformity Lumbar spine T-score Total Vertebral deformity Multiple vertebral deformities Fracture Grade 2 or 3 n % n % a n % b n % a Osteoporotic (T-score ≤−2.5). 93 28 39 47.0 41.9 20 54 51.3 32 55.2 34.4 Osteopenic (T-score −2.4 − −1.1). 126 37 25 30.1 19.8 12 32 48.0 16 27.6 12.7 Normal 118 35 19 22.9 16.1 5 14 26.3 10 17.2 8.5 Totals 337 100 83 100  37 100  58 100  p p a b 2 2 p 2 p 2 2 2 Table 2 n BMI Total Vertebral deformity Multiple vertebral deformities Fracture Grade 2 or 3 n % n % % n % % n % % Underweight <18 20 6.0 8 9.6 40.0 5 13.5 62.5 8 13.8 40.0 Normal 19–24 111 33.0 39 47.0 35.1 20 54.1 51.3 24 41.4 21.6 25–29 118 35.1 22 26.5 18.6 6 16.2 27.3 17 29.3 14.4 30+ 87 25.9 14 16.9 16.1 6 16.2 42.9 9 15.5 10.3 Totals 336 100 83 100  37 100  58 100  p p 3 p Table 3 Impact of prior fracture history on prevalence of vertebral deformity   Total Vertebral deformity Multiple vertebral deformities Fracture Grade 2 or 3 n % n % % n % % n % % 0 241 71.5 49 59.0 20.3 24 64.9 49.0 35 60.3 14.5 1 or more 96 28.5 34 41.0 42.7 13 35.1 38.2 23 39.7 24.0 Totals 337 100 83 100  37 100  58 100  p p 1 p 2 2 p p p Discussion One-quarter of patients presenting to our Fracture Liaison Service with a non-vertebral fracture had a previously undiagnosed vertebral deformity, of which almost one-half (45%) were multiple vertebral deformities. This is similar to the prevalence seen in previous studies using radiographic or MXA detection in women with and without non-vertebral fracture. Sub-analysis of patients by grade of deformity revealed that almost three-quarters of the patients had vertebral deformities of Grade 2 and Grade 3. These are more likely to be vertebral fractures, rather than vertebral deformities of non-osteoporosis aetiology, which might be more likely where Grade 1 deformities are present. 11 15 16 2 15 17 18 17 18 In this study, five of the 118 patients with normal BMD (4.2%) had two or more previously undiagnosed vertebral deformities plus a new non-vertebral fracture, and 25 of the 126 patients with osteopenic BMD (19.8%) had one or more previously undiagnosed vertebral deformities plus a non-vertebral fracture. These patients would not have been candidates for anti-resorptive treatment if MXA had not been performed and their vertebral deformities identified. Therefore, one in 20 patients with a normal T-score and almost one in five patients with an osteopenic T-score would experience a change in management by virtue of their underlying vertebral deformity or deformities. Overall, 30 (8.9%) of the patients in this study would be eligible for treatment by virtue of their newly identified vertebral deformity., which means that 11 patients who present with a non-vertebral fracture would need to undergo vertebral morphometry in order to identify one patient who ought to be managed differently. This ‘Number Needed to Screen’ gives an indication of the number of patients for whom treatment recommendations would change after the identification of vertebral fracture. 19 20 Our results support the recommendation to perform vertebral morphometry in any patient who is referred for DXA testing after experiencing a non-vertebral fracture. Treatment decisions will then better reflect any given patient’s future absolute fracture risk. The 'Number Needed to Screen' if MXA is used in this way would be seven to identify one patient with vertebral deformity, and 14 to identify one patient with two or more vertebral deformities. 21 Lateral vertebral morphometry does have limitations; for example, it is less reliable than conventional lateral spine X-rays at the upper thoracic spine and in Grade 1 deformities. 22 23 22 23 Given that the sample population had already had at least one non-vertebral fracture (28% had more than one prior fracture), were drawn from the FLS population, and that almost three-quarters had Grade 2 or 3 vertebral deformity, it seems reasonable to expect the vertebral deformity to be due to osteoporosis, rather than other diagnoses such as degenerative change or Scheurmann’s disease. 24 In conclusion, undiagnosed vertebral deformity is highly prevalent in patients aged over 50 years who present with a new non-vertebral fracture. Given that prior vertebral fracture significantly increases the risk of further fracture and because newer diagnostic techniques make identification of vertebral deformity consistent with fracture relatively straightforward with minimal radiation exposure, we recommend that all patients undergoing DXA should also undergo vertebral morphometry to identify prior vertebral deformities consistent with fractures.