Trauma | September 2021

Variable Angle Locking Patella Plating System

Eladio Saura-Sanchez, Karl Stoffel, Mark Lee, Cong-Feng Luo, Rodrigo Pesantez, Dean Lorich, David Helfet, Stephen Warner, Christoph Sommer


Patella fractures account for about 1 percent of all skeletal fractures. Despite the low incidence, the consequences of inadequate fracture treatment are potentially disabling. Tension band wiring with Kirschner wires (K wires) or cannulated screws is frequently performed. High rates of symptomatic hardware and loss of fixation have been reported for these fixation techniques.

The Variable Angle Locking Patella Plating System was developed to reduce these complication rates. The system offers two plating solutions in titanium and stainless steel:

  • 2.7 mm Variable Angle Locking Anterior Patella Plates (Fig 1)

  • 2.4/2.7 mm Variable Angle Locking Lateral Rim Patella Plates (Fig 2)

The most appropriate plate version can be chosen based on fracture pattern, soft tissue conditions and the preferred surgical technique. Both plate versions have variable angle locking holes which enable up to 15-degree of screw angulation to target small bone fragments and to avoid fracture lines and other hardware. The low-profile plates allow surgeons to achieve stable fixation in simple and complex patella fractures while minimizing soft tissue irritation. The plates can be cut and contoured with dedicated instruments to meet the patient anatomy and to address various fracture patterns. Sutures can be placed through the plate windows to anchor soft tissues. The repeatable surgical technique minimizes the user variation which is observed for tension band wiring.

Fig 1a-b Variable angle locking anterior patella plate. For distal to proximal screw placement through the distal patella pole a longitudinal split should be made in the patellar tendon to insert the plate leg.


Fig 2a-b Variable angle locking lateral rim patella plate. When placing the plate, the lateral rim of the plate should be contoured first to the bone to sit beneath the patellar ligament and the quadriceps tendon.

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