Chapter 18 Complications of Intraarticular Joint Injections and Musculoskeletal Injections

Chapter Synopsis: Intraarticular joint and musculoskeletal injections are considered among the least invasive interventional therapies for chronic pain; nevertheless, the procedures carry inherent risks. Complications associated with intraarticular injection can arise from needle misplacement, causing bleeding, infection, or nerve injury, or from interactions with the injectate itself. Injected air can result in air embolism, and hyaluronic acid injection can produce synovitis. The risks of trigger point injection are usually limited to pain at the injection site, but infection and damage to surrounding structures can uncommonly arise.

Important Points:

There should be a constant awareness of potential complications from interventional pain procedures, and efforts to minimize these complications should be implemented.

Although uncommon, complications from intraarticular injections arise from needle placement or the injectate itself.

Trigger points are arguably considered among the safest interventions in a pain practice; however, they are not without risk. This risk includes tenderness at injection site, bleeding, infection, and injury to nearby structures.

Introduction

Over recent years, interventional pain management has grown steadily. Consequently, the prevention of complications from interventional pain procedures should be a very important aspect of pain management. Although the true incidence is difficult to assess, it is extremely important to note and understand the potential risks and consequences. Appendicular intraarticular joint (hip, knee, shoulder, hand) and musculoskeletal injections are deemed some of the safest procedures performed in interventional pain management. The most common complications are infection, although septic arthritis, osteomyelitis, peripheral nerve injuries, pneumothorax, and skeletal muscle toxicity have all been reported (Table 18-1). The use of ultrasonography or fluoroscopy can assist in the visualization of nearby structures, thus decreasing the incidence of damage of these structures.

Table 18-1 Potential Complications and Avoidance at Each Site

Joint	Problem	Avoidance
Hip joint	Infection Neurovascular (femoral) injury Air embolism Synovitis	Meticulous sterile technique Ultrasonography for visualization Minimal air for injectate Reasonable concentration of corticosteroid
Shoulder joint	Infection Neurovascular (axillary or brachial plexus) injury	Meticulous sterile technique Ultrasonography
Knee joint	Infection Neurovascular injury	Meticulous sterile technique Ultrasonography
Intramuscular or trigger point	Bleeding Infection Myositis Injury to nearby structures	Use smaller gauge needle Meticulous sterile technique Avoid myotoxic local anesthetic (i.e., bupivacaine) Ultrasonography for visualization

Hip Joint Injections

Hip injection is a common procedure to alleviate hip pain because this is a location commonly affected by osteoarthritis (Fig. 18-1). Complications are rare with hip joint injections with proper patient selection, proper sterile technique, and appropriate injection technique. As with other injections, potential complications include bleeding or bruising, infection, allergic reaction to injectate, and increased pain. Injury to the femoral neurovascular bundle is a theoretical complication using an anterior approach to the hip joint, although it has yet to be described. The use of ultrasonography would allow visualization of this neurovascular bundle and would decrease the possibility of injury. Cheng and Abdil¹ (2007) describe air embolism in three pediatric patients undergoing hip injections. During arthrography, injections of a small amount of air can be used to outline the joint for correct needle placement. These injections were done with even small amounts of air (<5 mL). This has not been described in the adult population.