INJECTION THERAPIES

Injection Therapies in Orthopaedics are commonly used for both diagnostic and therapeutic purposes. They can help reduce inflammation, relieve pain, promote healing, and improve joint or soft tissue function.

🔹 Types of Injection Therapies in Orthopaedics

1. Corticosteroid Injections

Indications:

Osteoarthritis (e.g. knee, shoulder)

Bursitis (e.g. subacromial, trochanteric)

Tendinitis/Tendinopathies (e.g. rotator cuff, tennis elbow)

Inflammatory arthritis

Mechanism: Potent anti-inflammatory effect

Common Drugs: Triamcinolone, Methylprednisolone, Dexamethasone

Limitations: Limited frequency (risk of tissue damage), potential systemic effects (e.g. hyperglycemia)

2. Viscosupplementation (Hyaluronic Acid Injections)

Indications: Knee osteoarthritis (main use)

Mechanism: Lubricates the joint, improves shock absorption

Effectiveness: Variable; more effective in early-stage OA

Example: Synvisc, Orthovisc, Hyalgan

3. Platelet-Rich Plasma (PRP) Injections

Indications:

Tendinopathies (e.g. tennis elbow, Achilles tendinitis)

Early osteoarthritis

Muscle and ligament injuries

Mechanism: Uses patient’s own blood components to promote healing

Pros: Autologous, lower risk of reaction

Limitations: High variability in efficacy; expensive

4. Stem Cell Therapy (Mesenchymal Stem Cells)

Indications: Under investigation for cartilage repair, OA, tendon injuries

Mechanism: Regenerative potential

Status: Still mostly experimental; limited clinical approval

5. Local Anesthetic Injections

Indications: Diagnostic use in pain localization; short-term relief

Drugs: Lidocaine, Bupivacaine

Used With: Often combined with corticosteroids

6. Botulinum Toxin (Botox)

Indications: Spasticity, chronic pain conditions (off-label in some cases)

Mechanism: Blocks acetylcholine at neuromuscular junction

7. Prolotherapy

Indications: Chronic ligament/tendon pain

Mechanism: Injection of irritant (e.g. dextrose) to promote healing response

Controversial: Limited high-quality evidence

🔹 Common Sites for Injections

Shoulder: Subacromial bursa, glenohumeral joint, AC joint

Knee: Intra-articular space

Hip: Trochanteric bursa, intra-articular

Spine: Facet joints, epidural space

Foot/Ankle: Plantar fascia, tibiotalar joint

Elbow/Wrist: Lateral epicondyle, carpal tunnel

🔹 Risks and Complications

Infection

Post-injection flare

Skin depigmentation or atrophy (especially with steroids)

Tendon rupture (if injected into tendon)

Nerve injury