When Is Surgery Necessary For Osteoarthritis Of The Knee? | Decision-Making Guide

Written By on January 17, 2022 — Medically Reviewed By Kris Ceniza (PT)

Written by on January 17, 2022 — Medically Reviewed By: Kris Ceniza (PT)

If you have knee osteoarthritis, it’s natural to wonder when surgery is necessary. The short answer is that you’ll need surgery when your quality of life has severely deteriorated due to arthritis.

The catch is that this is extremely subjective. For an athlete, it can be the inability to play sports. For others, it might be having so much knee pain that they can’t sleep.

So, consider your own circumstances and think hard on whether surgery is the only/best option for you to live the best quality of life. This article will be a guide to help you make an informed decision.

Here’s what you’ll learn. Tap on any of the topics to jump straight to their sections:

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Undergoing surgery might be necessary for knee osteoarthritis if…

  • The pain is so severe you can’t do your daily activities
  • You avoid going out, walking, or climbing stairs for fear of making pain worse
  • The knee pain doesn’t let you rest or sleep
  • NSAIDs, injections, and home treatments don’t relieve symptoms
  • You don’t feel improvement after 6-12 months of physiotherapy
  • You’re unable to move your knee either from pain or deformity (i.e. locked knee) despite months of rehabilitation
  • Your x-rays show signs of severe wear and tear

P.S.: The criteria listed above are referenced from the BioMedCentral Musculoskeletal Disorders and the Royal Australian College of General Practitioners.

If you decide to go through surgery, the next step is knowing which of the many surgical techniques your orthopedic surgeon will perform.

Common types of knee surgery for osteoarthritis

Knee arthroscopy

A knee joint receiving arthroscopy for osteoarthritis, with the cannula, the arthroscope. and the arthroscopic instrument inserted

Arthroscopic surgery is a minimally invasive procedure. Here, the surgeon uses a tiny camera to check your knee joint and repair some of the damaged cartilage.

Who needs knee arthroscopic surgery?

Although a popular procedure, most medical associations don’t recommend it unless the patient has a locked knee. (1, 3)

More specifically, people over 40 years old with locked knees that already tried physiotherapy and injections without success. (4)

Knee Force Knee Sleeve

Arthroscopic surgery can have the same results as physical therapy and injections but the latter two don’t have as many potential side effects. (1, 3)

Knee osteotomy

A tibia bone with a wedge removed

In a tibial osteotomy, the surgeon removes a wedge of the shin bone to reduce the pressure on one side of the knee joint.

Who needs knee osteotomy?

Nowadays, a knee osteotomy is generally done on young people with knee arthritis on one side of the joint (i.e. unicompartmental arthritis) and bow leg deformities caused by knee OA. (4)

This can delay the need for knee replacement by as much as 10 years. (4)

But, some people will need another surgery to remove the hardware once the bone heals. Keep this in mind as it will increase the total cost of your recovery. (3)

Knee replacement surgery

People with severe arthritis symptoms often choose this procedure. Knee replacement surgery substitutes the damaged area with an artificial joint.

It can relieve pain significantly and improve the quality of life of the patient.

However, the surgeon must make sure the patient qualifies for this procedure. Research shows that up to 25% of people who have had knee replacement surgery didn’t need it. (1)

With that said, there are two types of knee replacements:

Total knee replacement

A knee with a total knee replacement with arrows pointing at its different parts - the femoral component, the plastic spacer, and the tibial component

Otherwise known as a “total knee arthroplasty”, the surgeon replaces the entire joint with a new one. It’s the most effective treatment for people in the end stage of knee osteoarthritis. (1)

However, note that 25% of people with knee replacements still have knee pain and disability and it might also come with significant side effects. (1, 4)

Who needs total knee replacement surgery?

People who meet these requirements meet the criteria for this surgery (1):

  • Significant physical limitations
  • Failed conservative treatment
  • Severe wear and tear on their x-rays
  • A BMI <30 and >20
  • A good mental health status

People with anxiety, depression, minimal pain, and obesity tend to have worse outcomes. (1)

Partial knee replacement

A knee joint with a partial knee replacement

Also known as “unicompartmental knee arthroplasty”, the surgeon only replaces part of the knee joint.

Who needs partial knee replacement surgery?

People with osteoarthritis on one side of the joint and without any deformities. The outcomes are very good with patients being more prone to return to sports than with total arthroplasty. (4)

Wait before having surgery for knee joint osteoarthritis if…

  • You can still do your daily activities in spite of the pain
  • You can manage your knee pain with medication, home treatments, and/or injections
  • The medication that gives you pain relief isn’t causing side effects
  • You have done less than a year of physiotherapy
  • You have some treatment options left to try
  • Your x-rays show mild wear and tear
  • Your knee doesn’t lock often
  • You are <40 years old

P.S.: The criteria listed above are referenced from the Royal Australian College of General Practitioners and the Annals of Physical and Rehabilitation Medicine.

Do you need surgery right now? Ask yourself these questions:

  • Have I really tried all treatments available for me?
  • Is knee surgery going to improve my lifestyle? How?
  • Am I fully aware of all the pros, cons, and risks involved in this surgery?
  • Did I discuss the realistic outcomes of this surgery with my surgeon?
  • Am I willing to commit to the physical therapy required after surgery?
  • Do I have a stable mental health? Or do I have anxiety and/or depression?
  • Is my BMI >30?
  • Do I have other health conditions that may increase the risk of complications?

If you answered “no” to any of the questions except for the last two, you should probably wait before you have surgery. Please discuss this further with your medical team.

This will help: Top 10 treatments for knee osteoarthritis according to evidence

Common (but effective) non-surgical treatments to try before getting surgery:

Physical therapy

Physical therapists are specially trained to manage joint pain, like the one from knee OA. So, regardless of the severity of your knee osteoarthritis, you can benefit from going to a physio. He/she will:

  • Reduce pain with active and passive strategies
  • Give you exercises to increase your muscle strength, which can delay the progression of OA
  • Guide you on how to manage your symptoms at home
  • Provide tactics to prevent and/or handle flare-ups

Home treatments

Knee osteoarthritis is a chronic condition. So, it will be in your best interest to know how to dial down the pain without turning to a doctor every single time. (1, 3)

Knee Force Knee Sleeve

The most common home treatments for knee osteoarthritis include:

This will help: 11 home treatments for knee osteoarthritis that actually work


What are signs that you need knee surgery for osteoarthritis?

These are common signs that mean you may need knee surgery (2):
– Moderate to severe knee pain that affects your daily activities
– No relief from conservative treatments, like physical therapy and medication
– X-rays showing severe wear and tear

Does osteoarthritis always require surgery?

No. Some people may avoid surgery if their symptoms are mild, if they’re young, and/or if they had an early diagnosis. (4)

How do I know if it is time for a knee replacement?

It’s time for knee replacement surgery if you have (1):
– Severe knee arthritis pain
– Failed conservative treatments
– X-rays that show severe knee osteoarthritis

Conclusion: Do you need surgery for arthritis in the knee?

Surgical treatment for wear and tear arthritis is extremely common. But, it’s also a very personal decision.

If you need surgery, your quality of life will improve greatly. If you don’t, it may do the exact opposite. Avoid this by asking yourself the questions above, while consulting with your surgeon and physio.


  1. The Royal Australian College of General Practitioners. Guideline for the management of knee and hip osteoarthritis. 2nd edn. East Melbourne, Vic: RACGP, 2018. Retrieved on December 2021 from: https://www.racgp.org.au/download/Documents/Guidelines/Musculoskeletal/guideline-for-the-management-of-knee-and-hip-oa-2nd-edition.pdf
  2. Gademan, Maaike G J et al. “Indication criteria for total hip or knee arthroplasty in osteoarthritis: a state-of-the-science overview.” BMC musculoskeletal disorders vol. 17, 1 463. 9 Nov. 2016, DOI: 10.1186/s12891-016-1325-z
  3. American Academy of Orthopaedic Surgeons Management of Osteoarthritis of the Knee (Non-Arthroplasty) Evidence-Based Clinical Practice Guideline (3rd Edition). https://www.aaos.org/oak3cpg Published August 31, 2021.
  4. de l’Escalopier, Nicolas et al. “Surgical treatments for osteoarthritis.” Annals of physical and rehabilitation medicine vol. 59, 3 (2016): 227-233. DOI: 10.1016/j.rehab.2016.04.003
Mitch Torres (PT)
Mitch is a physical therapist, personal trainer, and nutrition coach. Fascinated with the knee joint, Mitch poured that passion into writing about knee pain and how to overcome it with movement. His goal is to teach you how to apply this knowledge into your daily life, so you can keep knee pain away for good.