What is the sensitivity/specificity of X-rays in Lower Limb Stress Fractures.
Date First Published:
July 13, 2015
Last Updated:
July 13, 2015
Report by:
Alexander Bulcock, Medical Student (University of Manchester)
Search checked by:
Alexander Bulcock, University of Manchester
Three-Part Question:
In [patient with lower limb stress fractures] what is the [sensitivity and specificity of X-
ray] compared to [gold standard MRI for diagnosis]
Clinical Scenario:
A patient presents with a lower limb stress fracture and you wonder what the best first initial investigations should be. You arrange an X-ray of the lower limb, but wonder what the sensitivity and specificity of this investigation is.
Search Strategy:
Ovid MEDLINE(R) 1946 to July Week 1 2015
Search Details:
(exp Fractures, stress/ OR insufficiency fracture.mp./OR fatigue fracture.mp./ OR stress injury.mp.) AND (exp X-Ray/ OR plain film radiograph.mp./ OR x-ray.mp.) AND (exp sensitivity and specificity) Limit (English language AND humans AND all adults (<18-64 years))
Outcome:
17 hits
5 relevancies
5 relevancies
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Distinction of long bone stress fractures from pathologic fractures on cross-sectional imaging: how successful are we? Laura M Fayad 2005 USA | 59 patients: 30 biopsy proven pathologic fractures and 29 stress fractures | Retrospective cohort study to define CT and MRI features that distinguish pathologic fractures from stress fracture and compare CT and MRI with radiography | Sensitivity | Not given | Poor study design, no control, only 2 researchers involved. All x-rays had some feature in them therefore reviewers were primed to look for something. Not large enough study. Does not explain order of images presented. Overall poor study |
| Specificity | Not given | ||||
| CT vs X-ray | Radiography better than CT (94-88%) at distinguishing between pathological and stress fractures | ||||
| CT and MR imaging findings in athletes with early tibial stress injuries: comparison with bone scintigraphy findings and emphasis on cortical abnormalities. Michele Gaeta 2005 Italy | 42 patients: 16 female and 26 male All athletic, participated in sport |
Cohort study to compare CT, MRI and bone scintigraphy in athletes with clinically suspected early stress injury of tibia | MRI vs CT sensitivity | 88%: 42% | Did not compare against control group Used all modalities on all patients |
| MRI vs CT specificity | 100%: 100% | ||||
| Imaging of bone micro-injuries. V Boniotti 2002 Italy | 50 patients with bone micro injuries | Retrospective cohort study to identify the role of MRI in identifiying bone micro-injuries | X-ray sensitivity | 43.60% | Aim not clear Small sample size No control |
| X-ray specificity | 100% | ||||
| Longitudinal stress fractures of the tibia: comparative study of CT and MR imaging A Feydy 1998 France | 15 confirmed diagnosis of LSFT: 9 men and 6 women | Retrospective cohort study to compare the performance of CT and MRI in diagnosis of longitudinal stress fracture of the tibia | X-ray sensitivity | 6.50% | Poor study design, no control. All patients had all images done Only two radiologists assessed images Not clear aim to the study No clear parameters set |
| X-ray specificity | 100% | ||||
| Other key findings | MRI is the most sensitive and specific image 73% and 100% respectively | ||||
| [Diagnosis of stress fractures in adolescents] P Kasten 2005 Germany | 35 patients with average age of 12 | Cohort study to describe clinical and radiological findings in adolescent patients with stress fracture | X-ray sensitivity | 70% | Abstract only Used adolescents not adults Method unclear No follow up |
| X-ray specificity | 100% |
Author Commentary:
4 studies related to the question asked.
2 studies had limited relevance, one on adolescents and one used CT not X ray.
2 studies could not be accessed.
3 studies gave sensitivity of X-ray between 6.5%-43.6% (+70% in adolescents)
All studies gave specificity of X-rays at 100%
All studies recommended MRI as the imaging modality of choice.
2 studies had limited relevance, one on adolescents and one used CT not X ray.
2 studies could not be accessed.
3 studies gave sensitivity of X-ray between 6.5%-43.6% (+70% in adolescents)
All studies gave specificity of X-rays at 100%
All studies recommended MRI as the imaging modality of choice.
Bottom Line:
X-ray is specific to stress fractures but not sensitive and therefore a negative x-ray should not rule out a stress fracture.
References:
- Laura M Fayad. Distinction of long bone stress fractures from pathologic fractures on cross-sectional imaging: how successful are we?
- Michele Gaeta. CT and MR imaging findings in athletes with early tibial stress injuries: comparison with bone scintigraphy findings and emphasis on cortical abnormalities.
- V Boniotti. Imaging of bone micro-injuries.
- A Feydy. Longitudinal stress fractures of the tibia: comparative study of CT and MR imaging
- P Kasten. [Diagnosis of stress fractures in adolescents]