Joint and soft tissue injection
Acute and chronic pain in joints and soft tissues may benefit from injection of corticosteroids, local anesthetic or a combination with hyaluronidase, to enhance penetration of drugs and reabsorption of tissue fluid. This is usually a second line management, and requires precise localisation of the pain, stiffness or deformity by a full history and examination.
The injection may be into a joint cavity: although there are often a number of approaches to a joint, the standard techniques illustrated avoid major neurovascular structures. Injection into ligaments and bursae is into the tender area. In persistent tenosynovitis, the injection is into the tendon sheath, rather than the tendon itself. The latter may promote tendon rupture, and injection is not usually undertaken in the tendo Achilles, as this lacks a distinct sheath.
Injection techniques are considered in this chapter, rather than a separate section, so that they can be linked to the relevant anatomy and examination.
As with all invasive techniques, an aseptic technique is used, injection is not undertaken through infected tissues and full account is taken of potential injury to neurovascular structures and adjacent organs. After the first injection of a specific drug, observe the patient for 20–30 minutes to ensure there is no hypersensitivity to the agent.