Injections

1.1 General Principles

Clin Sports Med 1995;14:353; Geriatrics 1990;45:45; Curr Opin Rheumatol 1999;11:417

Medications:

Dexamethasone acetate (Decadron LA) 8 mg/cc
Triamcinolone diacetate (Aristocort) 40 mg/cc
Local anesthetics: lidocaine 1%, bupivacaine 0.25%

Mode of Action/Effects:

Inhibits release of prostaglandin synthesis, cytokines, and chemical mediators.
Inhibit activation and function of neutrophils, macrophages, fibroblasts, and basophils.

General Side Effects/Complications:

Local effects and complications: infection (very low risk with proper technique), nerve injury, pneumothorax, subcutaneous fat atrophy, skin color changes.
Allergic reactions: anesthetic or corticosteroid preparation.
Tendon and joint complications: tendon rupture, articular cartilage damage, osteoporosis.
Other reactions: steroid flare (2% of injections), vasovagal response (most common with upper extremity injections).
Diabetes mellitus: hyperglycemia.
Glaucoma: Reported potential complication. Rare in practice.

Contraindications:

Acute systemic infection, joint infection, or cellulitis at injection site.
Poorly controlled diabetes.
History of reaction to any components of injection solution.
Injection into a prosthetic joint or fracture site.

1.2 de Quervain’s Tenosynovitis

Indication:

Reduce pain in extensor pollicis brevis and abductor pollicis to allow adequate rehabilitation and tissue healing.

Anatomy:

EPB and abductor pollicis tendons contained in 1st dorsal wrist compartment.
Tendons form the dorsal and volar boundaries of the anatomic snuffbox.

Procedure:

25-gauge, 1½-inch needle is inserted at the anatomic snuffbox into the 1st dorsal wrist compartment directed proximally (Figure 1.1).

Medication:

1-2 cc dexamethasone acetate (Decadron LA) 8 mg/cc in 3 cc of lidocaine (1%).
1-2 cc triamcinolone (40 mg/cc) in 3 cc of lidocaine (1%).

Precautions:

Avoid injection into subcutaneous fat (may cause fat atrophy).
Superficial injection may cause skin discoloration.

Figure 1.1 de Quervain’s Tenosynovitis Injection

1.3 Trigger Finger

Indication:

Painful catching or locking of finger with active flexion.

Anatomy:

Flexor tendon nodule typically just proximal to MCP joint.
Will translate with active flexion/extension of the affected digit.

Procedure:

Using a 5/8-inch, 25-gauge instill solution into flexor tendon sheath at the palpable nodule (Figure 1.2).

Figure 1.2 Trigger Finger Injection

Medication:

¾ cc dexamethasone acetate (Decadron LA) 8 mg/cc in 3 cc of lidocaine (1%).
¾ cc triamcinolone (40 mg/cc) in ¼ cc of lidocaine (1%).

Precautions:

Ensure that pain is not the result of infectious flexor tenosynovitis.
Avoid injection into subcutaneous fat (may cause fat atrophy).

1.4 Extensor Carpi Ulnaris

Indication:

Ulnar wrist pain related to inflammation of the ECU tendon.

Anatomy:

ECU tendon palpable at distal ulna with swelling in the sheath often appreciated several cm proximal from this point.

Procedure:

Medial wrist at the distal ulna is sterilely prepared and a 1½-inch, 25-gauge needle is inserted at the distal ulna directed proximally. Solution should be palpable as it fills the ECU sheath (Figure 1.3).

Medication:

1-2 cc dexamethasone acetate (Decadron LA) 8 mg/cc in 3 cc of lidocaine (1%).
1-2 cc triamcinolone (40 mg/cc) in 3 cc of lidocaine (1%).

Figure 1.3 Extensor Carpi Ulnaris Tendon injection

Precautions:

Avoid injection into subcutaneous fat (may cause fat atrophy).
Superficial injection may cause skin discoloration.

1.5 Triangular Fibrocartilage Complex

Indication:

Chronic ulnar-sided wrist pain due to tear or degeneration of the TFCC.

Anatomy:

TFCC fills the space between the distal ulna (ulnar styloid) and proximal medial carpus.

Procedure:

After sterile prep, solution is injected through a 1½-inch, 25-gauge needle via a medial approach. The needle is inserted just distal to the ulnar styloid (Figure 1.4).

Medication: