Overview
- Improves stability where ligament reconstruction alone is likely to fail
- Varus with lateral thrust overloads posterolateral reconstructions
- Opening wedge HTO unloads these structures
- Reducing posterior slope protects the ACL
- Increasing slope helps the PCL deficient knee
- Alone, staged or combined with ligament reconstruction
- Assess alignment on long leg films and slope on lateral radiographs
Medial Collateral Ligament Injuries of the Knee
Posterior Cruciate Injuries of the Knee
Dislocations of the Knee
Osteotomies for Knee Instability
Pathology
- Increased posterior tibial slope increases anterior translation and ACL graft force
- Varus loads lateral and posterolateral structures and cruciate grafts, causing varus thrust
Classification
Noyes
| Type | Description |
|---|---|
| Primary varus | Osseous tibiofemoral varus |
| Double varus | Adds lateral tibiofemoral separation from lateral laxity |
| Triple varus | Adds varus recurvatum from posterolateral and posterior capsular insufficiency |
Original publication Noyes FR, Barber-Westin SD, Hewett TE. High tibial osteotomy and ligament reconstruction for varus angulated anterior cruciate ligament-deficient knees. Am J Sports Med. 2000;28(3):282-96.
Investigations
- Standing long leg films for mechanical axis and joint line obliquity
- Lateral films for slope
- Correction calculated by Miniaci or Dugdale methods or software
Management
- Medial opening wedge, biplanar with lateral hinge and plate, no fibular osteotomy, less peroneal risk
- Opening wedge raises slope unless the anterior gap is smaller, and may lower patellar height
- Lateral closing wedge needs fibular osteotomy, unites fast and decreases slope
- Failed ACL reconstruction with slope over about 12 degrees, slope reducing osteotomy plus revision
- Varus medial degeneration in young ACL deficient patients, HTO avoiding any slope increase
- Chronic PCL deficiency, slope increasing osteotomy
- PLC deficiency with varus, medial opening wedge first, as reconstruction in varus stretches out
- Instability without arthritis targets a neutral or slightly valgus axis
Complications
- Lateral hinge fracture with loss of correction
- Non-union, more common with opening wedge
- Peroneal nerve palsy with closing wedge
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.