Anesthetic Joint Injections
Percutaneous injections of joints with anesthetic agents have long been employed in the diagnosis and treatment of multiple joint disorders. The mechanism of action of intra-articular anesthetic injections is variable because structures including the joint capsule, synovium, intrinsic ligaments, and exposed subchondral bone underlying cartilage defects are in direct contact with the administered agents (1). Injections utilized primarily in the symptomatic treatment of patients affected by osteoarthrosis or inflammatory synovial processes are referred to as therapeutic injections. Anesthetic joint injections may also be requested during the preoperative evaluation of patients especially during the evaluation for joint arthrodesis or arthroplasty. These are known as diagnostic injections. This chapter will describe the general techniques involved in the injection of a variety of articular compartments with anesthetic agents and the objective evaluation of diagnostic injections.