Safety and efficacy of intraarticular hip injection using anatomic landmarks.

This study tests the hypotheses that the hip can be injected safely and reliably, using anatomic landmarks, without fluoroscopic guidance. 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. Neither the anterior nor the lateral injection approach, using published techniques based on anatomic landmarks, was sufficiently reliable to recommend for clinical use without radiographic guidance; the anterior approach was successful in only 60% of injections, and the lateral technique was successful in 80% of injections. In addition, the anterior approach, which is recommended in more reference works than any other approach, resulted in significantly more risk to the femoral nerve than did the lateral approach. 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 neurovascular structure in any injection. Some form of radiographic or sonographic guidance is recommended for needle placement during hip injections and aspirations; the lateral approach for needle placement seems safer than the anterior approach, with respect to the possibility of neurovascular injury.