Knee Realignment Procedures

I commonly perform osteotomy procedures around the knee - osteotomy means changing the shape or alignment of a bone. It is performed to treat and prevent the progression of arthritis, which commonly develops on only one side of the knee. The operation involves creating a wedge to partially divide the bone, to change the alignment of the leg, and then fixing it in the new position with a strong metal plate and screws.

VARUS VALGUS

HTO

Generally used to treat varus alignment and medial compartment osteoarthritis, when patients are 'bow legged'.

DFO

Generally used to treat valgus alignment and lateral compartment osteoarthritis, when patients are 'knock kneed'.

Osteotomy surgery can reduce the progression of osteoarthritis within the knee joint, and delay the need for knee replacement surgery. It does not replace the damaged cartilage, but offloads the area by changing where the force is placed through the knee joint, with the aim of relieving pain and improving function. It is a useful alternative for patients who are too young, or highly active, to consider a knee joint replacement.

The knee has evolved to be a highly complex hinge joint lined with articular cartilage at the end of the bones. Osteoarthritis occurs when this cartilage starts to thin and wear away. This often affects just one compartment in the knee, most commonly the medial on the inside part of your knee. Osteoarthritis can worsen if there is damage to the meniscus, or the stabilising ligaments in the knee (commonly the ACL).

Most people when they stand and walk put more pressure through one side of their knee than the other. By creating a wedge of bone in either the tibia or femur, you can change where this weight bearing axis lies. By moving this to the opposite side just past the midline, it takes the pressure off the damaged part of your knee to help relieve pain and improve function.

Before surgery I will often get you to try wearing an offloader knee brace. This simulates the effect of the procedure, and provides an experience of what your symptoms will be like after the operation.

High Tibial Osteotomy (HTO)

It is vitally important that with any osteotomy surgery you do not smoke, or vape, as this can impair bone healing. I also advise patients to take vitamin D and calcium supplementation to improve bone healing potential.

The surgery is generally performed under a general anaesthetic with a nerve block to help control pain. I will often perform knee arthroscopy (keyhole surgery) as part of the procedure to deal with any meniscal or cartilage pathology. Under x-ray guidance, in a controlled fashion through a small medial incision, I will create a biplane cut in the proximal tibial bone, based upon the pre-operative plan from long-leg alignment x-rays, to move the weight bearing axis towards the middle of the knee. Once the desired correction has been achieved the osteotomy is fixed with a plate and screws. Sometimes if it is a large correction I use allograft bone graft wedges to fill the defect.

Post-operatively it is key that your activity levels are designed to protect the osteotomy and allow it to heal. The leg will be bruised and swollen, and it is crucial to use ice therapy and the medication prescribed to help with the pain and swelling. Even though the osteotomy is stable, I advise patients to mobilise with crutches for the first 6 weeks following the procedure. It takes around 6 months until you are back to normal function.

HTO is often performed for medial compartment osteoarthritis to offload damaged cartilage on the inside part of your knee.

It is often a medial opening wedge procedure, stabilised with a plate and screws.

Distal Femoral Osteotomy (DFO)

A distal femoral osteotomy (DFO) is an osteotomy that occurs in the lower portion of your thigh bone. It is performed for either lateral compartment osteoarthritis caused by valgus (knock-kneed) alignment, or less frequently in cases of recurrent patella instability to correct rotational alignment problems.

It can also be combined with a HTO, in cases of severe deformity, to perform a double level osteotomy (DLO). This is uncommon, and if it is to be performed often utilises patient specific instrumentation (PSI).

It is vitally important that with any osteotomy surgery you do not smoke, or vape, as this can impair bone healing. I also advise patients to take vitamin D and calcium supplementation to improve bone healing potential.

DFO is often performed for lateral compartment osteoarthritis to offload damaged cartilage on the outside part of your knee.

It is often a medial closing wedge procedure, stabilised with a plate and screws.

Similar to HTO, the surgery is generally performed under a general anaesthetic with a nerve block to help control pain. I will often perform knee arthroscopy (keyhole surgery) as part of the procedure to deal with any meniscal or cartilage pathology. Under x-ray guidance, in a controlled fashion through a small medial incision, I will create a biplane cut in the distal femoral bone, based upon the pre-operative plan from long-leg alignment x-rays, to move the weight bearing axis towards the middle of the knee. Once the desired correction has been achieved the osteotomy is fixed with a plate and screws. Sometimes an additional screw is used to compress the osteotomy to provide additional stability.

Post-operatively it is key that your activity levels are designed to protect the osteotomy and allow it to heal. The leg will be bruised and swollen, and it is crucial to use ice therapy and the medication prescribed to help with the pain and swelling. Even though the osteotomy is stable, I advise patients to mobilise with crutches for the first 6 weeks following the procedure. It takes around 6 months until you are back to normal function.