Treatment of femur pseudoarthrosis using wave plate: Evaluation of consolidation and its relationship with graft type

Abstract

Introduction: In the pathogenesis of femoral pseudoarthrosis, the arched shape of the bone is important when determining traction force on the anterolateral plane and posteromedial compression. In plate osteosynthesis, flexion forces affect the implant and can determine its breakdown and osteosynthesis failure. The wave plate seeks to solve the problem by transferring the support to the cortex under the plate or creating the resistance of a leaf spring.

Objectives: To evaluate the bone healing pattern of femoral pseudoarthrosis treated with wave plate and its effectiveness in consolidation.

Materials and methods: We retrospectively evaluated 18 patients with femoral pseudoarthrosis treated with wave plate.

Results: Three months after surgery, one patient presented healing of pseudoarthrosis, six months after surgery, 16 patients presented healing of pseudoarthrosis and at 12 months, all patients had complete bone healing. Regarding the type of pseudoarthrosis, nine patients had avascular and nine vascular pseudoarthrosis. Fifteen patients had medial cortical failure and three, lateral cortical failure. In all cases, consolidation started where there was bone failure, be it medial or lateral.

Discussion: The wave plate technique is well indicated for the existence of cortical bone failure, both in fractures and in pseudoarthrosis. Objective is to stabilize the fragments by transferring and allowing contact between them. The formation of the bone callus occurred in our sample from the region of the bone defect to the region of bone contact, using either a tricortical or cancellous bone graft. The elastic force of the wave and the eccentric distribution of loads in the femur favored the formation of a callus where it was distracted (bone failure) and the location with concentration of movement (proximity between the fragments) was the end of bone healing.

Conclusion: The wave plate technique was effective in bone healing of femoral pseudoarthrosis, promoting consolidation from the cortical failure to the bone contact zone.

Keywords: bone plates; femoral fractures; femur; fracture fixation, internal; fracture healing; pseudarthrosis.