I specialise in realignment osteotomies around the knees and am a faculty to teach in various courses nationally and internationally about osteotomies. Double osteotomies/ Derotation osteotomies and Slope changing osteotomies are some of the complex surgeries I specialise.

Alignment and osteotomy

Normally, on a standing full length X ray of your lower limb (What we call a scannogram), the Weight Bearing Axis- the line of transmission of force of your body weight, passes through the centre of the hip joint, centre of knee joint and centre of ankle joint; meaning these three joints are aligned in a straight line. Any variation in this will lead to abnormal loading of the knee joint either on the inside (which is more common and is associated with bow legs) or the outside.

Alignment abnormalities are commonly associated with onset of arthritis (OA) and related problems. Early intervention in the form of realignment osteotomy will significantly slow down the progression of arthrosis and allow one to become active again.

It’s essential to understand the correct location of deformity; plan the required correction and then perform the appropriate procedure to realign the lower limb.

In close to 90% of patients with knee OA, there is bowing of the legs, meaning that the distance between the knees is increased leading to a bow leg deformity. This is commonly associated with a typical waddling gait. In such a scenario, significant amount of force is transmitted thro the damaged inner half of the knee- leading to collapse and further knee bowing.

If left untreated this quickly leads to damage to the ligaments and other stabilisers in the knee further causing a rapidly progressive OA in knee; the treatment for which is a Total Knee Replacement. If the alignment is addressed early on, then cartilage damage can be prevented/ slowed down and a normal function can be achieved along with delaying of arthrosis. Once the location and nature of deformity is ascertained, then appropriate realignment osteotomy is performed.

Osteotomy Planning: I use the "Traumacad" software (Brainlab, USA) or Bone Ninja software to assess the exact nature [Location, severity and associated factors included] of the limb deformity. This software is very sensitive and allows me to plan the necessary procedure in great details.

Surgery: The surgical procedure itself is fairly straight forward and involves performing and fixing the osteotomy with a metal/ PEEK (a kind of specialised hardened plastic) plate. Most patients can start walking in 2 days' time with a gradual increase in weight bearing. In about 6 weeks the osteotomy heals and most patients are back to normal activities soon after that.

The steps involved in realignment osteotomy surgery include:

• Pre-operative planning with X-rays to determine the degree of correction required with the osteotomy.
• Use of a saw to cut through the bone (tibia or femur) for which the osteotomy is planned.
• Change in the bone alignment to match the pre-operative plan.

  Opening wedge osteotomy: This involves opening the gap where the osteotomy has been made to change the alignment (as shown in the diagram).

  Closing wedge osteotomy: This involves removing a wedge of bone at the osteotomy site to change the alignment.

• Fixing the new alignment with a metal plate and screws. In opening wedge osteotomy, sometimes a bone graft is packed at the osteotomy site to fill in the gap. This is usually performed if a significant correction is required.

I have recently published an article on using these surgeries cleverly for treating ligament injuries of the knee as well. (Details in publications)