Load bearing vs load sharing

Load bearing requires large and rigid plates as they bear all the forces of function at the fracture site and provide absolute stability.

Load bearing is accomplished using these plates, ideally in combination with locking screws.

Load bearing is needed in cases with bone fragment instability.

Clinical uses include the management of atrophic edentulous fractures (insufficient bone stock), comminuted fractures, other complex mandibular fractures, and spanning an infected bone segment (defect).

Load-sharing osteosynthesis allows the use of smaller plates to provide relative stability due to the buttressing provided by the bony construct on either side of a simple fracture.

In the illustration the green arrows represent load sharing that occurs at the angle of the mandible.

Load-sharing osteosynthesis cannot be used with defect fractures or comminuted fractures due to the fracture site's lack of bony buttressing.

Maxime Champy popularized the treatment of mandible fractures with miniplate fixation along the ideal lines of osteosynthesis. This approach is a form of load-sharing osteosynthesis applied in simple, well-buttressed fracture patterns with an acceptable amount of bone stock.

Click here for a description of the biomechanics of the mandible.