MRI vs Bone scan in detection of suspected fractured neck of femur with normal plain radiographs in Emergency Department
Date First Published:
February 14, 2007
Last Updated:
September 7, 2010
Report by:
Richard Pilling, Orthopaedic Clinical Research Fellow (Hull & East Yorkshire NHS Trust)
Search checked by:
John Davies, Hull & East Yorkshire NHS Trust
Three-Part Question:
In [patient with suspected fracture of neck of femur and normal plain xray of the hip in emergency department] is [MR scanning more sensitive than Bone scan] in [detecting occult fractures] ?
Clinical Scenario:
An 82 year old lady has been brought to ED complaining of hip pain having been found on the floor at her residential home. Clinical examination indicates likely fractured neck of femur. Plain AP and lateral radiographs of the hip demonstrate to obvious fracture. What is the most accurate investigation to rule out fracture?
Search Strategy:
Pubmed 19/7/2010, OVID Medline 1950-July week 1 2010, Web of Knowledge 19/7/2010
Search Details:
Pubmed: fracture$.mp AND ((MRI$.mp) OR bone scan$.mp)
OVID: exp Hip fractures /cl,di,ra AND (MRI$ OR bone scan$).mp
Web of Knowledge:Topic=(fracture$) AND Topic=(MRI) AND Topic=(bone scan)
Refined by: Languages=( ENGLISH ) AND Subject Areas=( ORTHOPEDICS )
OVID: exp Hip fractures /cl,di,ra AND (MRI$ OR bone scan$).mp
Web of Knowledge:Topic=(fracture$) AND Topic=(MRI) AND Topic=(bone scan)
Refined by: Languages=( ENGLISH ) AND Subject Areas=( ORTHOPEDICS )
Outcome:
PudMed:149 articles found, 147 irrelevant to the study question.
OVID:109 articles, no new articles relevant to the study question.
Web of Knowledge: 167 articles, no new articles relevant to the study question.
Reference review: 1 further article
OVID:109 articles, no new articles relevant to the study question.
Web of Knowledge: 167 articles, no new articles relevant to the study question.
Reference review: 1 further article
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Comparison of MRI wih Bone Scanning foir Suspected Hip Fracture in Elderly Patients Evans PD, Wilson C, Lyons K 1994 UK | 37 pateints with suspected occult hip fractures investigated with MRI scan (within 24 hours) and bone scan (after 48 hours) |
Prospective cohort study |
Senstivity and accuracy of MRI compared with bone scan in detecting fracture of proximal femur | 8 of 37 patients had fractures. All 8 diagnosed by MRI. 6 of 8 diagnosed by bone scan. | Small study numbers. No blinding of investigators to outcome of other scan reported. |
| Magnetic Resonance Imaging: a cost effective alternative to bone scintigraphy in the evaluation of patients with suspected hip fractures Rubin SJ, Marquardt JD, Gottlieb RH, Meyers SP, Totterman SMS, O'Mara RE 1998 USA | 40 patients with suspected occult hip fracture underwent either MRI within (24 hours) or bone scan( within 72 hours). 21 patients recieved bone scan, 19 MRI. |
Retrospective cohort study |
Sensitivity | MRI: 100% bone scan:90.9% | Retrospective study. No criteria for allocating pateints to a group, bone scan patients diagnosed during first half of study, MRI second half. |
| Specificity | MRI: 100% bone scan: 100% | ||||
| Accuracy | MRI: 100% bone scan: 95% | ||||
| Time to Diagnosis | MRI: .0368+/-0.587 days. bone scan: 2.21+/-1.30 days p=<0.0001 | ||||
| Cost effectiveness | MRI:$3050.75 bone scan:$7543 | ||||
| Diagnosis of Occult Fractures about the Hip Rizzo PF, Gould ES, Lyden JP, Asnis SE 1993 USA | 66 patients with occult fractured neck of femur. All investigated with limited MRI within 24 hours and bone scan within 72 hours |
Prospective cohort study |
accuracy of MRI compared with bone scan in detecting fracture of proximal femur | 23 patients had negative MRI and bone scan. 36 patients had evidence of fracuture with both MRI and bone scan. 1 patient had positive MRI and negaive bone scan (re-scan at 6 days demonstrated fracture) | No blinding of investigators to outcome of other scan. |
| Sensitivity of MRI compared with bone scan in detecting fracture of proxiaml femur | MRI with in 24 hours showed greater sensitivity then bone scan at 72 hours |
Author Commentary:
Only a few small cohort studies comparing the two investigations directly however all reach the same conclusion that MRI demonstrates equal or greater sensitivity at detecting fractures. The speed and availability of MRI is a major factor as fractures are evident immediately with MRI whereas bone scans incur a delay before investigation and evidence of fracture is not guaranteed by 72 hours. The British Orthopaedic Association guidelines recommend that fractured neck of femur should be operated within 48 hours of admission, clearly this is not always possible with bone scan.
Bottom Line:
MRI is more sensitive, cost effective and accurate at detecting a fracture in an occult hip fracture than bone scans. Where available MRI should be the investigation of choice.
References:
- Evans PD, Wilson C, Lyons K. Comparison of MRI wih Bone Scanning foir Suspected Hip Fracture in Elderly Patients
- Rubin SJ, Marquardt JD, Gottlieb RH, Meyers SP, Totterman SMS, O'Mara RE. Magnetic Resonance Imaging: a cost effective alternative to bone scintigraphy in the evaluation of patients with suspected hip fractures
- Rizzo PF, Gould ES, Lyden JP, Asnis SE. Diagnosis of Occult Fractures about the Hip