Osteotomy is the surgical procedure of cutting and reshaping bone to correct alignment, redistribute joint loading, treat deformities (congenital, developmental, post-traumatic), or facilitate fracture healing. The fundamental principle is mechanical: shifting load from a damaged or overloaded compartment to a healthier one, restoring physiologic alignment, and preserving the native joint—particularly valuable in younger, more active patients (typically <60 years) for whom joint replacement may have shorter survival or activity restrictions. Osteotomies are categorized by anatomic location, geometric pattern (opening wedge with bone graft, closing wedge with bone removal, dome, oblique), plane of correction (frontal, sagittal, axial, multiplanar), and stabilization (plate-screw construct, intramedullary device, external fixator, hexapod—Taylor Spatial Frame).
Common procedures: high tibial osteotomy (HTO)—medial opening wedge or lateral closing wedge, indicated for medial compartment knee osteoarthritis with varus alignment in active patient; goals: shift mechanical axis to lateral compartment to unload medial compartment; biomechanical principle: 3-5 degrees of valgus overcorrection. Distal femoral osteotomy (DFO)—medial closing wedge or lateral opening wedge, indicated for lateral compartment OA with valgus alignment; combined HTO-DFO for severe deformity. Periacetabular osteotomy (PAO, Bernese/Ganz)—four cuts (ischial, superior pubic, posterior column, supra-acetabular) freeing acetabular fragment for repositioning, indicated for symptomatic hip dysplasia in adolescents/young adults to improve coverage and delay arthritis. Pelvic osteotomies for pediatric hip dysplasia (Salter, Pemberton, Dega, Chiari). Corrective osteotomies for fracture malunion to restore length, alignment, rotation. Tarsal/calcaneal osteotomies for foot deformities (cavovarus, planovalgus). Spine osteotomies for fixed sagittal/coronal deformity (Smith-Petersen, pedicle subtraction, vertebral column resection). Distraction osteotomies for limb lengthening (Ilizarov technique, intramedullary nail with distraction).
Surgical principles and modern advances: preoperative planning with full-length standing radiographs, CT, EOS imaging for 3D analysis; mechanical and anatomic axis measurement; precision determination of correction angle and wedge size; choice of opening (preserves bone, requires graft) versus closing (immediate stability, shortens bone) wedge; computer-assisted planning and navigation; 3D-printed patient-specific cutting guides increasingly used for HTO and complex corrections improving accuracy; biological considerations: bone graft (autograft from iliac crest, allograft, synthetic) for opening wedges, BMP-2 in selected cases, smoking cessation for healing; rigid stabilization with locking plates, intramedullary nails, or external fixators including hexapod (Taylor Spatial Frame) for gradual correction. Postoperative care: protected weight bearing typically 6-12 weeks, gradual progression, physical therapy for range of motion and strengthening, follow-up radiographs assessing healing and alignment maintenance, plate removal if symptomatic. Outcomes: HTO 10-year survival 75-90% with delay of arthroplasty, especially in lateralized mechanical axis correction; PAO 20-year hip preservation 60-70%; complications include nonunion (5-10%), malunion, infection (1-5%), neurovascular injury (rare but possible—peroneal in HTO/DFO, sciatic in PAO), DVT, hardware irritation, recurrent deformity. Patient selection critical: appropriate alignment, intact ligaments, preserved meniscus and cartilage in compartment to be loaded, BMI <30 ideal, motivation for rehabilitation.