Why is the procedure for Osteotomy done for?
Osteotomy is done for different purposes like deformity correction, prevention of progression of arthritis, stimulate and promote union in fracture non-union, prevent failure of ligament reconstruction and cartilage repair.
- Deformity Correction: Genu valgum and Genu Varum of knee, Coxa Valga and Coxa Vara of hip, intra articular varus or valgus deformity of ankle and elbow. Knee and hip deformity is usually developmental but can be from post-traumatic whereas elbow and ankle deformities are predominantly post traumatic.
- Prevention of progression of arthritis: in early osteoarthritis of the knee to shift the weight bearing axis on the lateral side of knee joint to relieve stress on damaged cartilage surface so that pain relief and secondary cartilage healing can start.
- Stimulate and promote union in fracture non-union: In case of fracture non-union of fracture neck of femur osteotomy at proximal femur done to shift weight bearing line perpendicular to fracture line and convert the share force to compression force on fracture for stimulation of fracture union.
- Prevent failure of ligament reconstruction and cartilage repair: Some times ACL reconstruction fails due to abnormal intra-articular alignment of tibia and which need to be corrected to negate the abnormal force acting on graft and increase the survival and acceptance of graft. Many times this is done during the primary reconstruction of ligament if this factor is suspected for possible failure or with cartilage repair and posterior root repair of medial meniscus to increase the chance of success of the surgical procedure.
What are the different choices for Fixation of Osteotomy?
Mostly anatomical plates are being used nowadays to fix the osteotomy with or without augmentation of graft (Bone substitute, allograft, autograft). In paediatric cases simple staples sometimes can suffice fixation.
How is the procedure done?
Before surgery appropriate whole length alignment x-rays are done to calculate the deformity as well as source of the deformity (intra-articular, metaphyseal, from shaft). This is done for pre operative planning and calculation where the osteotomy to be done (level) and how much correction to be done (osteotomy opening angle and distance osteotomy opening or block of bone to be removed to get the desired correction). During surgery the planned plane and angle of osteotomy is identified and marked with wire under c-arm guidance.
Following confirmation of the osteotomy plane it is completed with an oscillating saw under direct and C-arm visual control. Following completion of osteotomy (controlled measured fracture of bone) either it is open or closed after removal of bone block and correction checked under C-arm. Following achieving desired correction as planned at pre-operative planning it is fixed with a specific anatomical plate. If the gap is significantly large then a bone graft or a bone substitute is placed to fill the gap and support the osteotomy.
How does recovery happen?
Recovery of osteotomy is early and definitive. Early recovery is relief from post-surgical pain and becomes comfortable for guarded activity. Which usually takes 1-2 weeks. Definitive recovery is bony union of osteotomy, healing of ligament graft or meniscal repair for which the osteotomy is being done. Bony healing means union of osteotomy happens between 8-12 weeks post-surgery. During this period one is allowed to walk partial weight bearing with the help of elbow crutches. Allowed to walk full weight bearing after radiological confirmation of bony union. In some instances fixation plates need to be removed like in case of paediatric deformity correction to avoid future difficulties and in proximal tibia osteotomy because it causes hardware impingement.
What should you expect from the procedure?
One should expect reasonable deformity correction and improvement in gait if it is being done for developmental deformity. Relief of pain improves joint function and better quality of life if it is being done for early osteoarthritis or post traumatic deformity related arthritis. And successful incorporation of graft (tendon or cartilage) and healing of meniscal repair if it is done for failed ligament repair, cartilage injury and meniscal injury.
What are the Different Osteotomies done for Different Joints:
- Osteotomy for hip joint-
1) Developmental deformity like coxa valga, coxa vara, DDH, perthes disease, SCFE
2) Non-union of Neck of femur or malunion of subtrochanteric femur
3) Adult AVN of head of femur
4) Osteotomy of acetabulum to increase coverage and reducibility of head of femur within the acetabular cup
- Osteotomy Around Knee Joint
1) Osteotomy of distal femur to correct genu valgum or genu varum deformity (developmental or post rickets sequelae)
2) Osteotomy of proximal tibia to correct genu valgum or genu varum deformity (developmental or post rickets sequelae)
3) Osteotomy of proximal tibia; medial opening in early OA for delay the progression of disease
4) Osteotomy of proximal tibia; to correct proximal tibia slope and varus deformity to increase the success of ligament reconstruction or some time improve the stability of knee in case of ligament insufficiency cannot be reconstructed.
5) Osteotomy to correct post fracture deformity due to mal union of periarticular fracture.
- Osteotomy Around Ankle
1) As a definitive treatment of ankle arthritis due to post traumatic deformity or arthritis of ankle
2) Correct congenital deformity
3) Improve ankle instability by realigning leg heel axis.