Is it safe to fly after my knee replacement?

Last reviewed: September 29, 2026

Probably, for most people, but no study has settled how soon.

Surgery and long flights each raise the risk of blood clots in the legs, which can travel to the lungs. The question is whether flying adds to that risk after surgery.

The few studies are small. In the largest, people who flew home within days of a hip or knee replacement had no more clots than people who did not fly. A study of people who took long flights before surgery found the same. But a study from Scotland found more clots in people who took short flights to and from the hospital, though it counted only a handful of clots. Clots were uncommon in every group, so none of these studies can rule out a small difference.

In the general population, the longer the flight, the higher the clot risk. For ordinary travelers on flights over four hours, compression stockings greatly reduce clots that cause no symptoms. That has not been studied after a knee replacement.

No guideline sets a waiting time. Surgeons’ advice ranges from two weeks to six months, and some airlines and travel insurers ask for a doctor’s note.

In general:

• Ask your surgeon before booking a flight, especially in the first weeks.
• A long flight is a bigger question than a short one.
• Ask whether you need extra clot protection for the trip.
• Pain, swelling or tenderness in the calf after a flight needs to be seen promptly.
• Sudden shortness of breath or chest pain needs emergency care.

Drafted with AI assistance from published sources, reviewed and edited by Babak Sheikh, MD.

Sources:

• Elmenawi KA, et al. When Is It Safe for Patients to Air Travel After Total Hip and Knee Arthroplasty: A Comprehensive Review. JBJS Rev. 2025. https://doi.org/10.2106/JBJS.RVW.25.00014
• Cooper HJ, et al. Risk of Symptomatic Venous Thromboembolism Associated With Flying in the Early Postoperative Period Following Elective Total Hip and Knee Arthroplasty. J Arthroplasty. 2014. https://doi.org/10.1016/j.arth.2014.01.005
• Citak M, et al. Are Patients With Preoperative Air Travel at Higher Risk for Venous Thromboembolism Following Primary Total Hip and Knee Arthroplasty? Technol Health Care. 2015. https://doi.org/10.3233/THC-150893
• Mahmood F, et al. Perioperative Air Travel Increases the Risk of Venous Thromboembolism Following Lower Limb Arthroplasty. Eur J Orthop Surg Traumatol. 2022. https://doi.org/10.1007/s00590-022-03229-8
• Chandra D, et al. Meta-Analysis: Travel and Risk for Venous Thromboembolism. Ann Intern Med. 2009. https://doi.org/10.7326/0003-4819-151-3-200908040-00129
• Kuipers S, et al. The Absolute Risk of Venous Thrombosis After Air Travel: A Cohort Study of 8,755 Employees of International Organisations. PLoS Med. 2007. https://doi.org/10.1371/journal.pmed.0040290
• Clarke MJ, et al. Compression Stockings for Preventing Deep Vein Thrombosis in Airline Passengers. Cochrane Database Syst Rev. 2021. https://doi.org/10.1002/14651858.CD004002.pub4
• Oputa TJ, et al. Is There a Consensus on Air Travel Following Hip and Knee Arthroplasty? Cureus. 2023. https://doi.org/10.7759/cureus.43814

This is general information about what published research shows. It is not medical advice and it is not about your situation. Reading it does not create a doctor-patient relationship with me. I am a retired orthopedic surgeon and I do not see patients. Talk with your own doctor before changing anything about your care. If something feels suddenly or seriously wrong, get medical care promptly rather than waiting.

This page is provided as is. I make no guarantee that it is accurate, complete or current, and medical evidence changes. Use of it is at your own risk.

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