What is Distal Femoral Osteotomy?
An osteotomy is a surgical procedure that involves cutting of bone. The distal femur is part of the femur (thighbone) just above the knee joint. Distal femoral osteotomy is performed to correct knee malalignment. The procedure involves cutting of the distal femur, repositioning the bones and securing them in the proper alignment.
Who might be suitable for Distal Femur Osteotomy?
Malalignment of the bones at the knee joint may be present at birth or may gradually develop due to trauma or arthritis. Two types of deformity usually occur:
- Genu varum: The tibia (shinbone) turns inwards in relation to the femur causing a bow-legged deformity.
- Genu valgus: The tibia turns outwards in relation to the femur causing a knock-knee deformity
A distal femoral osteotomy is sometimes recommended if you have a deformity originating in the femur causing early degeneration in either the outer or inner part of the knee.
During a distal femoral osteotomy, the femur is lined up surgically so that the femoral axis passes through the centre of the knee and pressure on the damaged side of the knee joint is relieved.
Who might be suitable for Distal Femoral Osteotomy?
You may be a candidate for distal femoral osteotomy if you are:
- Less than 55 years old
- Physically active and healthy
- Normal BMI
- Affected by either medial or lateral arthritis only
Techniques of Distal Femoral Osteotomy
There are different techniques to perform a distal femoral osteotomy:
- Lateral (opening or closing) wedge osteotomy
- Medial (opening or closing) wedge osteotomy
The technique will depend upon the deformity and decided by pre-operative planning.
What happens in a Distal Femoral Osteotomy?
Distal femoral osteotomy is usually performed under general anaesthesia. The following technique is used:
- An incision is made over the distal femur where the osteotomy is to be performed. A medial wedge osteotomy is performed on the inside of the femur while a lateral wedge osteotomy is performed on the outside.
- The cut in the distal femur is made using an oscillating saw and a predetermined section of bone is removed.
- For a closing wedge osteotomy, a wedge-shaped section of bone is removed and the opening is closed by bringing the cut ends of the bones together, thus changing the alignment of the bones.
- For an opening wedge osteotomy, a cut is made into the bone and the gap is opened further using specific instruments to change the alignment of the bones. A bone graft may be inserted into the gap.
- The bones are secured in position with the help of metal plates and screws.
- The incision is closed and healing occurs the same way a fracture heals.
Recovery from Osteotomy Surgery
After the operation, bone healing may take upto 6 months. You will be mobile and fully weight-bearing relatively early following the surgery.
Benefits of Distal Femoral Osteotomy
Distal femoral osteotomy can:
- Reduce knee pain significantly
- Improve knee function
- Delay the need for knee replacement