You could go ahead and pick out a good book this summer. But why waste time on formulaic plots and slapdash characterizations when you could be reading great articles relevant to the Pediatric Emergency Department. Here’s another paper from the PEMBlog Summer Reading List!
Kocher et al.
J Bone Joint Surg Am. 1999 Dec;81(12):1662-70.
What this article is about?
This is a retrospective review of children with an acutely painful hip designed to help develop prediction rule for septic arthritis. Both univariate analysis and multiple logistic regression analysis were used to compare groups. This was the derivation study, and it was later validated in 2004.
Why is it important?
This article is the backbone of how we differentiate septic hip versus transient synovitis. Per Dr. Kocher himself, “Patients often presented similarly with atraumatic hip pain, limp, and fever. However, the differentiation is essential since septic arthritis is a surgical emergency with the potential for a poor outcome such as septic necrosis of the hip, whereas transient synovitis is treated with observation and has a generally benign outcome. The goal of the prediction rule was to make the diagnosis in a more accurate, reliable, and timely manner.” The authors noted the following four factors were important in the differentiation of septic hip versus transient synovitis;
- Fever
- Elevated WBC (>12,000)
- Elevated ESR >40
- Inability to bear weight
The combination of different features is spelled out in the paper – which you should read since it guides our practice – but in summary the likelihood of septic arthritis based on number of predictors was:
- 0 – <0.2%
- 1 – 3%
- 2 – 40%
- 3 – 93.1%
- 4 – 99.6%
How you can use it in your practice
In a child with an acutely painful hip that you are concerned could be septic arthritis obtain a CBC and ESR. In addition you will likely benefit from getting a blood culture and plain radiographs of the hip as well. In addition ultrasounds of the hip can help identify effusion.
This rule is for the hip and is not validated for use in other joints like the knee. You can extrapolate the results to the knee – but know where the evidence ends and your suppositions begin.
It is also important to note that the original prediction rule utilized ESR. CRP was not widely available yet. It does rise quicker, and ultimately a CRP >2.0 mg/dL could replace ESR in the prediction rule. Overall the performance between the two is similar.
What this article is about?
This is a retrospective review of children with an acutely painful hip designed to help develop prediction rule for septic arthritis. Both univariate analysis and multiple logistic regression analysis were used to compare groups. This was the derivation study, and it was later validated in 2004.
Why is it important?
This article is the backbone of how we differentiate septic hip versus transient synovitis. Per Dr. Kocher himself, “Patients often presented similarly with atraumatic hip pain, limp, and fever. However, the differentiation is essential since septic arthritis is a surgical emergency with the potential for a poor outcome such as septic necrosis of the hip, whereas transient synovitis is treated with observation and has a generally benign outcome. The goal of the prediction rule was to make the diagnosis in a more accurate, reliable, and timely manner.” The authors noted the following four factors were important in the differentiation of septic hip versus transient synovitis;
- Fever
- Elevated WBC (>12,000)
- Elevated ESR >40
- Inability to bear weight
The combination of different features is spelled out in the paper – which you should read since it guides our practice – but in summary the likelihood of septic arthritis based on number of predictors was:
- 0 – <0.2%
- 1 – 3%
- 2 – 40%
- 3 – 93.1%
- 4 – 99.6%
How you can use it in your practice
In a child with an acutely painful hip that you are concerned could be septic arthritis obtain a CBC and ESR. In addition you will likely benefit from getting a blood culture and plain radiographs of the hip as well. In addition ultrasounds of the hip can help identify effusion.
This rule is for the hip and is not validated for use in other joints like the knee. You can extrapolate the results to the knee – but know where the evidence ends and your suppositions begin.
It is also important to note that the original prediction rule utilized ESR. CRP was not widely available yet. It does rise quicker, and ultimately a CRP >2.0 mg/dL could replace ESR in the prediction rule. Overall the performance between the two is similar.
