Lateral Epicondylitis (Tennis Elbow)

Evidence: Well-Supported — ASPN 2024: Level I · Grade B

CAUSES

• Repetitive wrist-extension motions — tennis backhands, racquet sports, painting, or typing
• Degeneration of the extensor tendon at the outer elbow
• Sudden increases in repetitive gripping or lifting
• Trauma

SYMPTOMS

• Pain and tenderness on the outer elbow (the thumb side when the palm is facing up)
• Pain that worsens with gripping, lifting, or extending the wrist against resistance
• Pain radiating down the outer forearm with activity

IMAGING WE’LL TYPICALLY ORDER

Ultrasound can show tendon thickening, tearing, or calcification. MRI is reserved for difficult to treat cases or when surgery is being planned.

CAN PRP HELP?

Tennis elbow is one of the best-supported uses of PRP, and one of ASPN’s highest-graded indications. A well-designed two-year trial found PRP clearly outperformed physical therapy, shockwave therapy, and prolotherapy, with the largest and most durable improvement in function and satisfaction. PRP also beats cortisone injection from about 3 months out to 2 years, though cortisone provides faster relief over the first several weeks.

Leukocyte Preparation: Leukocyte-Rich

Dosing: Single injection with reassessment and additional procedure as needed

Target Platelet Dose in Studied Protocols: At least ~1 billion platelets delivered.

ASPN 2024 CONSENSUS GUIDELINE

ASPN grades lateral epicondylitis Level I, Grade B, with a target dose of at least 1 billion platelets. The leukocyte-rich-vs-poor question remains genuinely open even at this evidence level: a 2026 blinded RCT found a modest MRI-based edge for leukocyte-rich PRP in shrinking partial tear size, while a separate 2026 meta-analysis found leukocyte-rich PRP causes more injection-site pain than leukocyte-poor (with no difference in serious adverse events). We keep the leukocyte-rich default here rather than switch, consistent with the guideline’s own read of the newest data.

Sources: D’Souza et al. (ASPN Consensus), Journal of Pain Research, 2024 · Walecka et al., Journal of Shoulder and Elbow Surgery, 2026 · Driscoll et al., Arthroscopy, 2026 · Lhee et al., American Journal of Sports Medicine, 2025

FREQUENTLY ASKED QUESTIONS

How does PRP compare to physical therapy or cortisone for tennis elbow?

In a well-designed two-year trial, PRP clearly outperformed physical therapy, shockwave therapy, and prolotherapy, with the largest and most durable improvement in function and satisfaction. It also beats corticosteroid injection from about three months out to two years, though corticosteroid still outperformed PRP in the first few weeks.

Leukocyte-rich or leukocyte-poor PRP for tennis elbow?

Leukocyte-rich is preferred when available, consistent with the guideline’s read of the newest evidence. A 2026 blinded trial found a modest edge for leukocyte-rich PRP in shrinking partial tear size on MRI, while a separate 2026 meta-analysis found it causes more injection-site pain than leukocyte-poor, with no difference in serious adverse events.

Does the amount of PRP injected matter for tennis elbow?

Yes, ASPN’s Level I, Grade B rating specifies a target dose of at least roughly 1 billion platelets delivered.