Patella fractures treated with cannulated lag screws and fiberwire® have a high union rate and low rate of implant removal

Injury. 2020 Feb;51(2):473-477. doi: 10.1016/j.injury.2019.10.002. Epub 2019 Oct 2.

Abstract

Objectives: The purpose of this study is to report the results of open reduction internal fixation of patella fractures (OTA 34 A-C) using cannulated lag screws and FiberWire® (Arthrex, Naples, FL, USA) with regard to union and symptomatic implant removal.

Design: Retrospective review of prospectively collected database.

Setting: Urban Level 1 trauma center and Level 2 trauma center METHODS: All displaced intra-articular patella fractures (OTA 34 A-C) treated with ORIF by cannulated lag screws and FiberWire® tension band/cerclage between January 1, 2009 and August 1, 2018. Three hundred and eighty seven consecutive patients were identified. Fifty fractures were included in the final analysis.

Main outcome measurement: All patients were followed to clinical and radiographic union. Nonunion was defined as lack of clinical and radiographic union, fracture displacement, and/or return to OR for revision surgery. Rate of symptomatic implant removal was recorded.

Results: Average age was 57.7 years (range 21-86). Average follow up was 20.6 months (range 6-98 months). Average time to clinical and radiographic union was 3.1 months (range 3-7 months). Four fractures were open. There was a 96% (48/50) rate of primary union, with one patients requiring revision surgery to achieve union, and one developing an asymptomatic radiographic nonunion. The rate of symptomatic implant removal was 8% (4/50). Only 1 of the 4 was operated for a prominent suture knot, and the remaining 3 were for prominent screw removal. Knee range of motion averaged 0.37° extension to 119° flexion (range, 0-150°).

Conclusion: Patella fractures can be treated with cannulated lag screws and FiberWire® with a high rate of primary union (96%) and a low rate of symptomatic implant removal (8%). The implant removal rate compares favorably with alternative constructs, with an equivalent rate of fracture union.

Keywords: Implant removal; Patella fracture; Tension band; Therapeutic Level IV; Union.

MeSH terms

  • Adult
  • Aftercare
  • Aged
  • Aged, 80 and over
  • Bone Screws / adverse effects*
  • Bone Wires / adverse effects
  • Device Removal / statistics & numerical data
  • Female
  • Fracture Fixation, Internal / instrumentation*
  • Fractures, Bone / classification
  • Fractures, Bone / complications
  • Fractures, Bone / surgery*
  • Fractures, Ununited / diagnostic imaging
  • Fractures, Ununited / epidemiology
  • Fractures, Ununited / surgery
  • Humans
  • Knee Joint / physiopathology
  • Knee Joint / surgery
  • Male
  • Middle Aged
  • Patella / injuries*
  • Radiography / methods
  • Range of Motion, Articular
  • Reoperation / statistics & numerical data
  • Retrospective Studies
  • Treatment Outcome