We always recommend locating the femoral vessels when performing the exam. Along with allowing the novice sonographer to understand relevant anatomy, ensuring that the probe is lateral to the femoral vessels when performing the in-plane ultrasound-guided hip arthrocentsis will prevent inadvertent vascular puncture.

I cannot find the needle on the ultrasound screen. What should I do?

Novice sonographers sometimes are unable to locate the needle on the ultrasound screen. When performing in-plane ultrasound procedures, stabilization of the ultrasound probe is key, and slight adjustment of the probe in a slight lateral or medial parasagittal plane might be required.

Also, in a patient with a large body habitus, the angle of the needle must be steeper, decreasing ultrasound needle visualization. In these cases, we recommend compressing superficial subcutaneous tissue with gentle probe pressure. Complete needle visualization may not be possible, making this a difficult procedure for the novice operator.

References

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