Bone-patellar tendon-bone graft (BPTB)

What it is

The patellar tendon runs from the bottom of the kneecap to the bump at the top of the shin. The surgeon takes roughly its middle third, about 9 to 11 millimetres wide, with a bone block at each end. The blocks are fitted into tunnels in the thighbone and shinbone and fixed, often with screws.

The bone ends heal into the tunnels much like a fracture heals, which gives firm early fixation.

Why it matters for patients

It has a long track record in pivoting sports such as football and basketball, and re-tear rates in young athletes are low. It is also useful in revision surgery.

The main drawback is front-of-knee discomfort, especially when kneeling. That can matter for prayer, floor sitting in the majlis, tiling or other kneeling work. There is also a small risk of kneecap fracture or tendon irritation, and the scar is at the front of the knee.

Who it suits

It is often offered to high-demand athletes with mature skeletons. It is usually avoided in children with open growth plates and used cautiously in people who kneel a lot or already have kneecap pain. The final choice follows examination and a discussion of your sport, work and daily life.