The usefullness of ultrasound scan in the evaluation of limping children presenting to the Emergency Department
Date First Published:
July 28, 2006
Last Updated:
June 12, 2012
Report by:
Vassilis Athanassoglou, SHO Emergency Medicine (Addenbrooke's Hospital)
Search checked by:
Duncan McAuley, Addenbrooke's Hospital
Three-Part Question:
In [children presenting to the Emergency Department with hip pain and limping] is [ultrasonography better than clinical parameters] in [differentiating septic arthritis from other hip conditions]?
Clinical Scenario:
A 5 year old boy presents to the Emergency Department with a 2 day history of limp and right hip pain he is afebrile. Is an ultrasound of the hip better at diagnosing septic arthritis than blood investigations (WBC, ESR, CRP)?
Search Strategy:
Dialog Datastar interface using specifically:
(CINAHL interface on the World Wide Web 1982 to date
EMBASE database on the World Wide Web 1974 to date
MEDLINE database on the World Wide Web 1950 to date)
(CINAHL interface on the World Wide Web 1982 to date
EMBASE database on the World Wide Web 1974 to date
MEDLINE database on the World Wide Web 1950 to date)
Search Details:
[(((ULTRASONOGRAPHY.W..DE.) OR (ultrasound ADJ scan) OR (ULTRASONOGRAPHY-DOPPLER.DE. OR ULTRASONOGRAPHY-DOPPLER-COLOR.DE.) OR (ultrasonography)) AND ((hip) OR (HIP-JOINT.DE.)) AND ((septic ADJ arthritis) OR (ARTHRITIS-INFECTIOUS#.DE.))) AND (LG=EN AND HUMAN=YES AND ( CHILD# OR ADOLESCENT.DE. OR
INFANT# ))]
INFANT# ))]
Outcome:
There were 42 papers identified using Dialog Datastar of which 4 were relevant. No single paper directly compared USS with blood investigations in the diagnosis of septic arthritis.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Sonography of the painful hip in children: 500 consecutive cases Miralles M, Gonzalez G, Pulpeiro JR et al. 1989 Spain | 500 consecutive children presenting with painful hip or limp | Prospective study | Presence or absence of effusion on USS | 261/500 (52%) had negative USS. | Did not look at clinical parameters. So of 7 cases septic arthritis 4 had abnormal USS, so sens was 4/7 (57%). |
| 235/500 (47%) had positive USS. | |||||
| 7/500 (1.4%) had septic arthritis. | |||||
| 3/500 (0.6%) had abnormal USS and XR. | |||||
| 1/500 (0.2%) had abnormal USS and normal XR. | |||||
| Joint effusion in children with an irritable hip: US diagnosis and aspiration. Zawin JK, Hoffer FA, Rand FF et al. 1993 USA | 90 consecutive children presenting with limp | Prospective study | USS diagnosis and aspiration result | 40/96 (42%) had negative USS of which 3 (7.5%) were diagnosed as ostelomyelitis and 0 septic arthiritis | Small numbers leading to high incidence of septic arthritis probably due to selection bias. Sensitivity for septic arthritis was 100%, but specificity was poor. |
| 56/96 (58%) had positive USS of which 15 (26.7%) were septic arthritis. | |||||
| The irritable hip: immediate ultrasound guided aspiration and prevention of hospital admission. Fink AM, Berman L, Edwards D et al. 1995 UK | 50 consecutive patients aged 1 to 10 years presenting to the Emergency Department with acute hip pain. | Prospective study | Presence or absence of septic arthritis and hip effusion on USS. | 36/50 (72%) had detectable effusions and were aspirated. | Small numbers, only 1 diagnosed septic joint, which had a detectable effusion on USS giving USS a sensitivity of 100% according to the study. |
| 35/36 (97%) of effusions showed no organisms on microscopy and remained sterile after 5 days. | |||||
| 1/50 (2%) had septic arthritis with WBC 20.4x109/l and ESR 30 mm/h. | |||||
| Causes of false-negative ultrasound scans in the diagnosis of septic arthritis of the hip in children. Gordon JE, Huang M, Dobbs M, Luhmann SJ et al. 2002 USA | All children with hip pain presenting during a 18 month period. | Prospective cohort study. | Presence or absence of hip effusion on USS and cause of effusion. | Of 132 patients, 80 had USS. | Population different to our ED population. Not all patients underwent USS, may be workup bias. |
| Of 22 SA, 18/80 (22.5%) had positive USS. | |||||
| 4/80 (5%) had septic arthritis but negative USS. |
Author Commentary:
There is a paucity of evidence that directly looks at this question. Some studies (Fink et al, Zawin et al) suggest that USS has an excellent sensitivity for detecting septic arthritis although other studies show a significant false negative rate (Miralles et al).
Bottom Line:
Based on the current available clinical evidence few recommendations can be made regarding routine use of USS in limping children. Perhaps using clinical and biochemical markers to identify high risk patients will allow focused use of ultrasonography. The question also remains as the best management of children with abnormal bioclinical markers but a normal USS scan.
References:
- Miralles M, Gonzalez G, Pulpeiro JR et al.. Sonography of the painful hip in children: 500 consecutive cases
- Zawin JK, Hoffer FA, Rand FF et al.. Joint effusion in children with an irritable hip: US diagnosis and aspiration.
- Fink AM, Berman L, Edwards D et al.. The irritable hip: immediate ultrasound guided aspiration and prevention of hospital admission.
- Gordon JE, Huang M, Dobbs M, Luhmann SJ et al.. Causes of false-negative ultrasound scans in the diagnosis of septic arthritis of the hip in children.