Planification préopératoire des ostéotomies autour du genou

Why proper pre-operative planning matters in knee osteotomies

In corrective osteotomies around the knee (varus or valgus deformities), the success of the surgery depends as much on the planning as on the surgical execution. Pre-operative planning determines the osteotomy level (femur, tibia or both), calculates the required correction angle, assesses hinge location, evaluates joint line obliquity (JLO) and ensures bone geometry accommodates the planned correction. This chapter emphasises that planning must go beyond simple axis correction and be tailored to the individual anatomy.

How the planning process is described and what tools are used

The authors outline the components of effective planning:

• Full-length standing radiographs to measure mechanical and anatomical axes of the lower limb (HKA, mLDFA, MPTA).
  
• Identification of the centre of rotation of angulation (CORA) for each deformity segment.
  
• Simulation of the osteotomy wedge or opening, calculation of wedge size from angular correction and estimation of hinge shift and bone contact geometry.
  
• Use of 3D imaging and patient-specific cutting guides or navigation when available to translate the plan into intra-operative action.
  
• Consideration of other planes (sagittal, axial) and soft-tissue constraints (ligaments, patellofemoral alignment) as part of the planning.

What key planning pitfalls and best practices are highlighted

• One common pitfall: planning only for mechanical axis correction without evaluating segmental deformity can lead to residual imbalance or joint line tilt.
  
• Best practice: localise whether deformity originates in femur, tibia or both, as correction at the wrong segment may induce new deformities.
  
• Hinge planning is critical: mis-placement can lead to cortical breach, non-union or loss of correction.
  
• Accurate simulation of wedge size is important: small errors in angle translate into significant bone translation and loading changes.
  
• Planning must include intra-operative verification strategies (fluoroscopy, navigation) and postoperative monitoring of correction accuracy.

How this chapter informs surgical decision-making and patient outcomes

Effective pre-operative planning influences surgical strategy: choice of osteotomy level, order of corrections (in double-level cases), fixation method, rehabilitation protocol and patient counselling. By applying robust planning frameworks, surgeons can reduce the risk of complications, achieve more predictable alignment correction, preserve joint line geometry, and give patients realistic expectations about recovery and long-term outcomes.

Key take-away messages for clinicians

1. Thorough pre-operative planning is the foundation of successful knee osteotomy — it must include segmental deformity analysis, simulation of correction and hinge design.
   
2. Planning should not end with axis correction; bone-specific geometric changes must be addressed to avoid joint line obliquity and secondary deformities.
   
3. Regular use of full-leg imaging, digital simulation and, where available, patient-specific instrumentation improves surgical accuracy and reproducibility.
   
4. Integrating planning into the surgical workflow and patient discussion supports both technical success and patient satisfaction.
   

Link to full paper: Planification préopératoire des ostéotomies autour du genou

Sources used in report overview:

1. https://www.researchgate.net/publication/356488430_Planification_preoperatoire_des_osteotomies_autour_du_genou?_tp=eyJjb250ZXh0Ijp7InBhZ2UiOiJzY2llbnRpZmljQ29udHJpYnV0aW9ucyIsInByZXZpb3VzUGFnZSI6bnVsbH19
2. https://theses.fr/2018AIXM0474 (Donnez M.) (theses.fr)
3. https://orthopedie-lyon-croix-rousse.fr/images/cours-diu/… (Saragaglia) (orthopedie-lyon-croix-rousse.fr)