In this next series of blog posts, I’m going to be talking about knee replacement surgery – everything from how knees work to preparing for surgery and maximising your recovery. This is part one, focusing on knee anatomy and when to consider surgery. You can also skip ahead to part two on prehab exercises or part three on recovery strategies.
Sarah’s story: the power of preparation
Sarah came to see me while she was on an 18-month waiting list for her knee replacement. At 67, she could barely walk to her local shop without stopping twice to rest. “I can’t imagine waiting this long in this condition,” she told me during our first consultation. We started a personalised prehab programme focusing specifically on her glute muscle weakness, restricted knee extension and walking technique.
Six months later, she told me: “I just walked my grandson to school – the whole mile there and back. I haven’t done that in three years!”
By the time Sarah had her surgery, she was stronger than she’d been in five years. Her surgeon was amazed at her recovery speed – she was off crutches in just 10 days, compared to the typical 3-4 weeks.
Understanding your knee: the foundation of effective prehab
Your knee is a bit more complex than just a simple hinge joint. Unlike a door hinge, it includes:
- A built-in rotation that allows it to “lock” into extension
- Three bones: the femur (thigh bone), tibia (shin bone), and patella (kneecap)
- Complex muscle interactions: the movements are affected not just by your thigh and calf muscles, but also by hip and foot/ankle muscles
The patella (kneecap) serves as a critical force multiplier, giving your quadriceps greater mechanical advantage – allowing you to sprint, jump, and climb stairs without needing massive thigh muscles.
When should you have a knee replacement?
Knee replacements become necessary when the joint is no longer functional due to:
- Accidents or trauma – fractures disrupting the joint surface
- Osteoarthritis – the most common reason, essentially “wear and tear” of the protective cartilage
What Causes Osteoarthritis?
- Trauma – previous injuries affecting the knee joint and causing cartilage damage
- Overuse – common in former athletes (especially from high-impact and twisting sports like football and rugby)
- Underuse – sedentary lifestyles creating stiffness and “wear points”
- Misuse – prolonged limping or compensation patterns
However, it’s important to note that most people over 30 have some degree of osteoarthritis, and that having wear and tear doesn’t automatically mean you need surgery. For example, I was diagnosed with shoulder arthritis at 24 from playing competitive tennis; but over two decades and hundreds of tennis matches later, I still don’t need a replacement.
I do not believe you should be offered a joint replacement unless you have joint damage combined with pain and loss of function, which cannot be controlled through conservative means, and which is interfering with your quality of life.
The waiting game: make the most of the delay
According to NHS England statistics, the 18-week target for routine operations hasn’t been consistently met since 2016. Many patients now wait 12+ months for knee replacement surgery.
But the waiting time doesn’t have to be wasted!
- A 2017 study in the Journal of Bone & Joint Surgery found that comprehensive prehab reduced post-surgery hospital stays by 29%
- Patients who completed structured prehab programmes also had much stronger quadriceps muscles and better function than those who didn’t.
When is the right time for surgery?
As top knee consultant Ian McDermott says: “Knee replacement surgery is a major op, not to be entered into lightly. You should only consider having knee replacement surgery if your symptoms and/or functional restrictions actually feel bad enough to justify the pain, the hassle, the time required for the rehab and the potential associated risks of surgery.”
The ideal timing requires careful balance:
- Too early? You might still benefit from non-surgical approaches
- Too late? You risk significant muscle weakness, making recovery harder
This delicate timing decision should involve you, your surgeon, and your physiotherapist working together to find the optimal moment for your specific situation.
Take control of your knee replacement journey
After working with hundreds of knee replacement patients over 20+ years, I’ve developed a quick assessment that helps identify exactly where your knee function stands now and what specific prehab would benefit you most.
Take my FREE 2-minute knee function assessment to discover:
- Your current knee function score
- Which specific muscle groups need the most attention
- Personalised exercise recommendations based on your results
- How your results compare to ideal pre-surgery levels
Don’t let your waiting time go to waste – try my 2-minute assessment to start your personalised prehab journey today and set yourself up for the best possible surgical outcome.
In my next post, I’ll cover exactly what exercises should be in your prehab programme based on your specific needs.
