Ultrasound navigation in the management of piriformis syndrome

Local injection therapy in the neurological practice is considered. The effectiveness of the targeting therapeutic injection directly into the trigger zone depends on the antispasmodic, anti-edema, analgesic and pathogenetically justified anti-inflammatory effect of a medicine. Piriformis syndrome, structural features of the musculoskeletal system and peripheral nervous system are discussed. Sciatic nerve formation occurs at the level of the sacral plexus (plexus sacralis). Plexus sacralis is the largest formation in the peripheral nervous system, consisting of the anterior branches of the L5, S1-S4 spinal nerves and the lower part of the anterior branch of L4. The cause of sciatic nerve compression-ischemic neuropathy is its compression by the piriformis muscle in the infrapiriformis foramen area. High damage of the sciatic nerve leads to the pathological injury of both of its components, tibial and common peroneal nerves. This condition is accompanied by paresis or paralysis of the foot and fingers (foot drop), the triceps surae reflex is lost, and the flexion of the lower leg is difficult. One of the main clinical signs of pathological changes in case of damage to the sciatic nerve is impaired sensitivity on the posterior and external surface of the lower leg, the back of the foot, in the fingers and sole. Among the instrumental diagnostic methods, the most informative ones are digital panoramic radiography of the spine, magnetic resonance imaging, and for some indication — densitometry and computed tomography. The use of the local injection therapy is studied. In piriformis syndrome, the zone of injection is calculated with the patient lying on their healthy side. The lower leg is straight, the upper leg is bent at the knee joint. The injected site is located at the intersection of a straight line connecting the ischial tuberosity and the apex of the iliac crest with a perpendicular drawn to it from the greater trochanter. Treatment-related damage to soft tissues, vessels and structures of the peripheral nervous system is possible, in particular traumatic damage to the sciatic nerve, post-injection temporary paresis of the lower limb or post-injection hematoma. Our long-term practical experience has demonstrated significant effectiveness, accuracy and safety of performing this procedure provided under ultrasound navigation.The routine use of ultrasound navigation during the local injection therapy for piriformis syndrome is an actual, accessible, and clinically substantiated imaging method that ensures high efficiency and final success of this manipulation.