Hip injections. Is there a need for ultrasound guidance?
For years there has been a debate amongst those performing intra-articular hip joint injections regarding the accuracy of intra-articular hip joint injections performed land mark guided also known as “blind or unguided”.
Some i.e Mauffrey et al (2005), who employed a lateral landmark guided approach found that in 20 patients undergoing hip injection 19 had the needle accurately placed. They concluded that in the hands of an experienced Orthopaedic surgeon hip injections could be carried out landmark guided.
This finding however is not supported by the majority of studies on accuracy of landmark guided injections and ultrasound guided injections.
Kurup et al, (2010) found in a cohort of 40 patients (43 hips). That Twenty-eight of the 43 hips (65.1%) were injected successfully with the blind technique without need for repositioning which is an unacceptable failure rate of 1 in 3 injections.
Smith et al (2008) wanted to determine the accuracy of sonographically guided intra- articular injections using contrast-enhanced fluoroscopy as a reference standard. Thirty hip injections were completed with 97% (n=29) of sonographically placed needles were accurately placed. They concluded that the oblique sagittal approach had acceptable accuracy.
A systematic review and meta-analysis by Hoeber et al (2015) comparing the accuracy of ultrasound (US)-guided versus landmark-guided hip joint injections included 4 US-guided (136 hip injections) and 5 landmark-guided (295 hip injections) studies. The weighted means for US-guided and landmark-guided hip injection accuracies were 100% (95% CI 98% to 100%) and 72% (95% CI 56% to 85%), respectively. US-guided hip injection accuracy was significantly higher than landmark-guided accuracy (p<0.0001). The authors concluded that their results supported the use of US guidance over landmark guidance in clinical practice.
Leopold et al 2001 tested the hypotheses that the hip can be injected safely and reliably, using anatomic landmarks. Fifteen human cadavers (30 hips) were injected, each receiving one anterior hip injection and one lateral hip injection with methylene blue dye. Anatomic dissections were done on all 30 specimens to determine the rate of success and the proximity of the needle to the neurovascular structures about the hip with each approach.
They found that neither technique was sufficiently reliable to recommend for clinical use without image guidance; the anterior approach was successful in only 60% of injections, and the lateral technique was successful in 80% of injections.
In terms of safety they found that the needle pierced or contacted the femoral nerve in 27% of anterior injections and was within 5 mm of the femoral nerve in 60% of anterior attempts. The anterior injection approach also resulted in needle placements significantly closer to the femoral artery and the lateral femoral cutaneous nerve than did the lateral approach. Using the lateral approach, the needle was never within 25 mm of any neuro- vascular structure in any injection.
In terms of accuracy there is evidence from a systematic review and meta-analysis (Hoeber, et al. 2015) that ultrasound guided injections are more accurate than landmark guided injections: 98%-100% vs 56-85% (CI = 95%).
Leopold et al (2001) showed that anterior hip injection via landmark guidance was only accurate in 60% of cases and that the needle pierced or contacted the femoral nerve in 27% of cases. The lateral approach was safe (no intra-neural injections) but was only 80% accurate. They concluded that injections should be performed under ultrasound guidance.
Sofka et al (2005) in their retrospective review of an ultrasound database revealed 358 adult hip aspirations/injections. There were no reported cases of inadvertent vascular or femoral nerve puncture.
The evidence on accuracy of injections in the hip joint clearly shows that ultrasound guided injections are much more accurate than landmark guided injections. Furthermore a study on landmark guided Cadaveric hip joint injections showed not only poor accuracy (60-80%) but also high rates (27%) of intraneural injection (femoral nerve).
Therefore injections of the hip joint both for reasons of accuracy and safety, should be done image guided with ultrasound guidance being an accurate and safe option.
Hoeber, S., Aly, A.R., Ashworth, N. and Rajasekaran, S., 2016. Ultrasound-guided hip joint injections are more accurate than landmark-guided injections: a systematic review and meta-analysis. Br J Sports Med, 50(7), pp.392-396.
Kurup, H. and Ward, P., 2010. Do we need radiological guidance for hip joint injections?. Acta orthopaedica Belgica, 76(2), p.205.
Leopold, S.S., Battista, V. and Oliverio, J.A., 2001. Safety and efficacy of intraarticular hip injection using anatomic landmarks. Clinical Orthopaedics and Related Research®, 391, pp.192-197.
Mauffrey, C., 2006. Pobbathy. Hip joint injection technique using anatomic landmarks: are we accurate?: A prospective study. The Internet Journal of Orthopedic Surgery, 3(1).
Smith, J., Hurdle, M.F.B. and Weingarten, T.N., 2009. Accuracy of Sonographically Guided Intra‐articular Injections in the Native Adult Hip. Journal of Ultrasound in Medicine, 28(3), pp.329-335.
Sofka, C.M., Saboeiro, G. and Adler, R.S., 2005. Ultrasound-guided adult hip injections. Journal of vascular and interventional radiology, 16(8), pp.1121-1123.