Patella Fractures: Approach to Treatment

Damayea I. Hargett, MD; Brent R. Sanderson, DO; Milton T.M. Little, MD

Disclosures

J Am Acad Orthop Surg. 2021;29(6):244-253. 

In This Article

Plate Fixation

Patella fracture plating has increased in popularity for the treatment of displaced, comminuted stellate, and inferior pole type injuries with improvements in low-profile plating options.

A diverse selection of plating options exists to treat the various patella fracture morphologies. Dorsal 2.7 mm fixed-angle plates and dorsally based x-shaped plates have been compared with tension band wiring for transverse patella fractures with excellent results.[19,30] Locking plate fixation has demonstrated increased ultimate strength of fixation when compared biomechanically with tension band fixation.[30] Wurm et al[31] demonstrated notably improved patellar fixation using an anatomically shaped locking plate with unicortical screws in comparison to cortical screws with tension-band wiring. During biomechanical testing, the tension band construct developed a 5 times larger fracture gap compared with plate fixation. In addition to biomechanical success, Wurm et al[31] reported only a 6% complication rate in the study participants. This complication rate is considerably lower than the complication rate typically reported for patella fractures treated with tension band wiring, which is estimated about 20% to 30%.[32] Their patients achieved 77% of full function, with patients complaints most commonly regarding kneeling or squatting.

Multiaxial longitudinal cortical and unicortical locked plating for comminuted fractures has been done with the use of a moldable low profile minifragment locked plate as well. This technique has demonstrated clinical and biomechanical superiority, with less fracture gap formation over tension band constructs.[33–36] The low-profile plate allows for the use of 2.4 and 2.7 mm cortical and locking screws through a variable angle mesh. Each plate is custom cut and contoured to fit the fracture morphology (Figures 2 and 3). These provide excellent fixation options for comminuted fractures in patients with and without osteoporotic bone.

Figure 2.

Intraoperative photograph of comminuted patella fracture in a 59-year-old woman after fall from ladder demonstrating (A) low profile minifragment mesh plate contoured to the patient's patella resulting in (B) anatomic reduction of the articular surface with a low-profile construct (C).

Figure 3.

Preoperative (A) AP and (B) lateral radiographs of 45-year-old male cyclist after fall off bicycle demonstrating a comminuted patella intra-articular fracture. One-year postoperative (C) AP and (D) lateral radiographs after fixation with a moldable low-profile minifragment mesh plate construct.

Mesh-type plating techniques have demonstrated successful radiographic union while limiting reoperations for nonunion, infection, and symptomatic outcomes.[35,37–39] In addition, patients have reported improved subjective outcome scores, thigh circumference, strength with closed and open chain knee exercise programs, and 70% less anterior knee pain compared with tension band constructs.[34] Prominent hardware is still a concern with patellar plating, but hardware removal rates have been reported between 0 and 11%[16,33,39,40] that is improved over previously reported removal rates of 32% to 37% with metal tension band constructs.[41]

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