Knee arthroscopy: an OR 101 guide
Reviewed by Rodnie Oro, cath lab charge nurse · Last reviewed: October 2026 · Education only, not medical advice
Knee arthroscopy in one minute
What it is: keyhole surgery using a camera to look inside the knee and treat problems such as meniscus tears or loose bodies.
Who it is for: people with mechanical symptoms such as locking, or specific injuries; it is not recommended for knee arthritis alone.
Main risks: infection, bleeding into the knee, stiffness, blood clots, nerve injury (rare).
Usually: under general or spinal anaesthetic, 30–60 minutes, home the same day.
On this page: What is knee arthroscopy? · Who is it for? · When is it done? · Step by step · Recovery · Risks · Kit list · First time in theatre? · FAQ
What is knee arthroscopy?
In arthroscopy the surgeon makes two or three small cuts and inserts a camera (arthroscope) and fine instruments. The knee is filled with fluid to see clearly.
It can be used to:
- trim (meniscectomy) or repair a torn meniscus, the cartilage cushions in the knee
- remove loose bodies
- treat some cartilage problems, or assist ligament surgery
Arthroscopic washout or trimming is not recommended for knee arthritis without locking, as per NICE guidance.
New to the acronyms? See the Cath Lab Abbreviations A–Z.
Who is it for?
It may be considered for people with:
- a meniscus tear causing locking or catching
- loose bodies in the knee
- some cartilage or ligament problems
The decision is made by your surgical team, who will talk through the reasons, the alternatives and the risks with you.
When is it done?
Most operations are planned; some are urgent. Before it, you usually have:
- an examination and X-rays, and sometimes a CT or MRI scan
- blood tests and, for bigger operations, an ECG
- a review of your medicines, especially blood thinners, as per centre protocol
- fasting instructions
- a chance to ask questions and give consent
Step by step
1. Getting ready
Team brief and WHO checklist first, including the implant check and confirming the site and side marking. The anaesthetic team and ODP give the anaesthetic (general or spinal, as per centre protocol); antibiotics and blood-clot prevention are given as per centre protocol. The circulating practitioner checks positioning and pressure areas, the diathermy plate, warming, the tourniquet, and radiation protection if X-ray is used. The scrub practitioner checks implant and instrument trays are complete and sterile, and does the first count. Theatre traffic is kept to a minimum, especially in laminar-flow theatres. The arthroscopy stack (camera, light, fluid pump and shaver) is checked.
2. Access
The patient lies on their back, often with a leg holder and a tourniquet. Two or three small ports are made around the kneecap.
3. Working inside the knee
- A. Ports and fluid. The camera is inserted and the knee filled with fluid.
- B. Inspection. Every area of the knee is checked systematically.
- C. Treatment. Torn meniscus is trimmed or repaired, or loose bodies removed.
- D. Washout. The knee is washed out and fluid drained.
4. Finishing
Ports are closed with stitches or strips, and a dressing and bandage applied. Final counts are confirmed, implant details recorded, and the patient goes to recovery with a full handover, including limb checks (circulation and nerves), as per centre protocol.
Recovery and aftercare
- Going home: the same day.
- Walking: usually straight away, sometimes with crutches; after meniscus repair, restrictions may apply.
- Swelling: ice and elevation help.
- Exercises: start gentle exercises as advised.
- Work: often 1–2 weeks off for desk work.
- Follow-up: as per centre protocol.
Call 999 if you have chest pain or sudden breathlessness. Contact your team if you have increasing pain, a cold, numb or very swollen limb, calf pain, fever, or a wound that becomes red, hot or leaky.
Risks and complications
Your team will explain the risks that apply to you. Possible problems include:
- infection
- bleeding into the knee
- stiffness or ongoing pain
- blood clots in the legs or lungs
- nerve or blood vessel injury (rare)
Theatre kit list (printable)
Example kit list
Every theatre has its own protocol, and sizes and doses vary.
- arthroscopy stack: camera, scope, light, fluid pump and shaver
- arthroscopy instruments (probe, punches, graspers)
- meniscal repair devices, per device and operator
- tourniquet and leg holder
- fluid bags and tubing
- closure strips or sutures and dressings
Procedural steps
- Team brief, WHO sign in; side marked; anaesthesia
- Supine; leg holder; tourniquet; prep and drape; count
- Ports; fluid; diagnostic round
- Treatment of findings
- Washout; photos for notes, per centre
- Closure; dressing; counts; sign out and handover
First time in theatre?
đź’ˇ First-time tip
- Implant check. Read back the implant type, side and size before opening, and record it in the implant log.
- Site and side. Check the marking at sign in and again before the cut.
- Counts matter. Swabs, needles, instruments and small implant parts are counted; speak up if one is missing.
- Tourniquet time. Note when the tourniquet goes up and call out times as per centre protocol.
- Fluid and camera. Keep the fluid bags topped up and check the camera is white-balanced and focused.
FAQ
Will it help my arthritis?
Not on its own; it is not recommended for arthritis without locking.
How big are the scars?
Small, around 1 cm each.
How soon can I walk?
Usually straight away.
Related guides
Sources
All checked on 14 October 2026. Each page's own date is shown where it gives one.
- NHS. Arthroscopy. nhs.uk/conditions/arthroscopy
- NICE. Osteoarthritis in over 16s: diagnosis and management (NG226). nice.org.uk/guidance/ng226
- StatPearls (NCBI Bookshelf), search: knee arthroscopy. ncbi.nlm.nih.gov/books
- World Health Organization. Surgical Safety Checklist. who.int
Disclaimer
Education only. This page is for general education for healthcare students, theatre staff and curious readers. It isn't medical advice and doesn't replace advice from your own doctor, surgical team or local unit protocols. Equipment and medicines are described generically. No product or manufacturer is recommended. If you think someone is having a medical emergency, call 999.
Disclosure: I work in the medical device industry. This page is independent education and isn't sponsored or reviewed by any company.
All diagrams on this page are original illustrations created for rodnieoro.com.
