The Meniscus and Articular Cartilage

These "C shaped" structures are also termed “cartilages” by many. There are 2 of these inside each knee, one on the inner (medial) side and the other on the outer (lateral) side.
They function as shock absorbers, load transfer units, and secondary stabilisers.
Tears of the meniscus occur frequently, and may result from a twisting injury or a more minor injury in older people.
The knee may have swelling, catching or locking, and pain usually is on one side of the joint.
Arthroscopic (Keyhole Surgery) techniques are employed to treat these tears by removing the unstable portion of the tear. In some instances, there may be an option to repair the tear.

The meniscus is essentially an "avascular" structure meaning it has very little blood supply except in its outermost (peripheral) area
This means that most tears cannot heal as they do not have a blood supply. These tears if problematic and unstable can be trimmed out through keyhole surgery
If the tear is in a zone where there is a blood supply and has a potential to heal, it may be repairable.
Most tears are not repairable, and the final decision is usually made during the keyhole procedure.
Meniscal knee cartilage repairs are performed using special stiches and instruments that can be placed inside the knee through keyhole surgery.
Repairing the meniscus may necessitate some immobilisation, or restricted weight bearing in the post operative period, and a delay to returning to full contact sports.
Repaired meniscii do not always heal, and sometimes further surgery may be required.

Articular (Hyaline) cartilage is the ultra smooth covering found on the ends of bones within a joint. It is an integral capping of the bone and is analogous to the tread on a car tyre. It undergoes wear and tear through life and this process may be accelerated in some individuals for a variety of reasons. Wear of articular cartilage leads to arthritis.
If a car is driven badly with fast cornering and lots of skids, then the tyres will wear very quickly. Similarly if the knee undergoes lots of injuries throughout its life, then the cartilage may wear more quickly.
However exercise is essential for healthy cartilage as the nutrition the cartilage needs is dissolved in the joint fluid and gets “pumped” into the cartilage during movements.
Excessive loads and malaligned wheels also cause tyres to bald quickly, and likewise being excessively overweight and having malalignment in the limb can cause accelerated cartilage wear.
As cartilage wears, it becomes roughened, and starts to fray. It may give rise to catching and creakiness within the knee joint.

Chondroplasty is a procedure done through keyhole surgery and involves shaving or ablating very rough unstable layers of articular cartilage to smoothen it, as seen in the photos which are before and after appearances during the procedure.
This keyhole procedure addresses cartilage wear include shaving the cartilage to give it a smoother finish, or using a radiofrequency probe (RF ablation). It may improve some symptoms by removing unstable flaps which catch and interfere with normal knee movement. The wear is still present and results for pain relief are not guaranteed.
In areas where there is complete wear down to bare bone microfracture can be performed.

$Microfracture knee technique. Small holes are made to promote stem cell release to repair cartilage$

Microfracture involves making small holes in the bone at regular intervals to create a surface clot, which over time matures into fibrocartilage, and resurfaces the area of bare bone. The blood released from the bone marrow has stem cells which forms the rational for this procedure.
Cartilage grafting is a very specialised procedure, usually done in two stages. It is another form of stem cell knee cartilage repair. Cells from the knee are harvested in the first stage, and grown in a laboratory before being transplanted back into the knee (second stage) with some form of specialised membrane.
Other new techniques for cartilage repair are being developed and remains an area of research and innovation

Osteotomy is realignment of the bones around the knee joint to off-load the worn out part of the joint. This procedure is carried out by specialists who work in close collaboration with Mr Siddiqui