Spring Plate 3.5

The Spring Plate 3.5 is intended for pelvic and acetabular reconstructive surgery. The plate is 10 mm wide and 1.2 mm thick. The bone surface has two 1.5 mm sharp teeth and a concave surface that is prebent to a 50 mm radius. It comes in lengths of 14 holes and will be available in stainless steel.

The Spring Plate 3.5 is intended to help reduce and stabilize small bone fragments when the fragments are too small to use a screw. Comminuted posterior wall fractures of the acetabulum are the most common indication. Plate function is achieved by sinking the teeth into the small fragments as a screw is tightened through one of the screw holes adjacent to the fracture margin. The screw transfers the prestress of the concave plate to a compressive force on the fragments, essentially acting as a permanent clamp. Alternatively this effect can be achieved with the low-profile pelvic reconstruction plate 3.5 which overlies the provisionally placed spring plate. As the reconstruction plate is lagged to the bone, the fracture fragments are compressed.

The Spring Plate may also be used occasionally in periarticular extremity applications.

18-year-old male-missed injury

Case provided by Keith Mayo, Tacoma

The superior plate is a modified one-third tubular plate and represents the forerunner of the production plate which is seen inferiorly. Joint space narrowing likely represents combined pre surgical cartilage loss and secondary subsidence of elevated and grafted areas of marginal impaction.


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