What is the knee joint?

The knee is a very important joint in the body and consists of the thigh bone (femur) and shin bone (tibia). It plays an extremely important role in supporting nearly the entire weight of the body and does this with the help of surrounding muscles, ligaments and cartilage. 

You have many muscles around your knee which help provide stability and allow movement. The main muscles surrounding the knee are the Quadriceps (front of thigh), Hamstrings (back of thigh) and Calf (back of lower leg). 

Ligaments hold your bones together and are therefore integral to stabilising the knee. Anterior Cruciate Ligament (ACL) prevents excessive forward movement of the tibia on the femur. Other important ligaments in the knee are the Posterior Cruciate Ligament (PCL), the Medial Collateral Ligament (MCL) and the Lateral Collateral Ligament (LCL).  

There are 2 types of cartilage: the Meniscus and Articular Cartilage. The menisci are disc shaped fibrous cartilage that are situated between the femur and tibia. They provide stability, act as shock absorbers, lubrication and allow equal weight distribution.

The Articular Cartilage covers the end of the bones and allows them to move smoothly against each other with less friction. It also helps spread the load applied to the joint.

Articular Cartilage Damage can be caused by trauma, degenerative changes (OA) or inflammatory disorders (RA). This leads to pain, swelling, locking, giving way, grinding sensation (crepitus). Articular cartilage does not have its own blood supply therefore has a limited capacity to heal.

What happens during surgery?

Chondroplasty

A chondroplasty is a surgical procedure which smooths over loose damaged articular cartilage flaps from the surface of the bone in the hope that healthy joint surface will heal over the defect.  It is normally indicated for small, shallow cartilage defects. A camera is used to look inside the knee and one or two instruments are inserted for the surgical procedure through small ‘key – hole’ incisions.

Microfracture

If the damaged articular cartilage is more severe where bare bone is exposed, a surgical procedure known as Microfracture may be performed. Microfracture surgery is performed arthroscopically. Microfracture procedure involves the surgeon making multiple holes deep into the bone where the cartilage is absent and allowing an influx of blood rich in growth factors to coat the bone surface. This forms into a clot and over time develops into new cartilage, also known as fibrous cartilage. A camera is used to look inside the knee and one or two instruments are inserted for the surgical procedure through small ‘key – hole’ incisions.

What should I expect after surgery?

Mobilisation

You will aim to mobilise on the day of your surgery, this may be with the use of elbow crutches depending on the site of your repair. You should also be able to go up and down stairs. The exercises that you can complete will depend on the site of the repair and any restrictions that your surgeon has requested. Your physiotherapist will teach you appropriate exercises before you are discharged home.

Pain relief

A nerve block is sometimes used during surgery which means your limb may feel numb immediately after your operation. It is normal to feel some pain as the block wears off and you will be provided with some painkillers to help with this. It is important to take these as prescribed to keep pain to a minimum. 

Ice

Ice can be helpful to reduce pain/swelling. Protect your dressings from getting wet with a plastic bag. Wrap a bag of ice/frozen peas in a damp towel and apply for 10-15 minutes. This can be repeated every 3-4 hours. For knee and foot surgery, elevating your leg on pillows can also help.

Wound care

Your wounds will need to be kept clean and dry. The nursing staff will provide you with more information about wound care on discharge.

Driving and work

You should not drive whilst using elbow crutches. Please discuss this further with your consultant or physiotherapist.  When you can return to work will depend on what job you do. Your physiotherapist will be able to advise you on this.

Leisure and sport

This will also depend on the extent of the surgery you have had and what activities you want to return to. Your consultant or physiotherapist can advise you further on this. 

More information

If you have any questions or need any advice about your exercises, then please contact the Physiotherapy Department between 8am - 4pm Monday to Friday on 0121 728 9442.