Outcomes for a custom-made anchor-like plate combined with cerclage in the treatment of inferior pole patellar fracture

Abstract

Objective: An inferior pole fracture of the patella requires surgical treatment to restore the knee extension mechanism of the knee joint. Different from other types of patellar fractures, inferior pole fractures are usually comminuted, and other traditional fixation methods, such as tension band wiring, may not meet the fixation needs. We propose fixing inferior pole fractures of the patella with a custom-made anchor-like plate combined with cerclage and report the surgical outcomes.

Material and methods: This is a retrospective clinical study. From June 2018 to August 2020, 21 patients with inferior patella fracture treated at Hong Hui Hospital Affiliated to Xi'an Jiaotong University received a custom-made anchor-like plate combined with cerclage. Complications of the surgical fixation methods and final knee function were used as the main outcome measures.

Results: All fractures achieved good union, and the union time ranged from 8 to 12 weeks. No patients had serious complications, such as internal fixation failure or infection. The average duration of surgery of patients was 75.05 7.26 min, and the intraoperative blood loss was 60.099.49 ml. At the last follow-up, the range of motion of the knee was 120°-140°, with an average of 131.436.92°, the Bostman score was 27-30, and the Lysholm score ranged from 82 to 95. All patients showed good knee function one year after the operation.

Conclusion: We used a modified T-shaped plate combined with cerclage technology to fix inferior fractures pole of the patella, providing reliable fixation, allowing early functional exercise of the knee joint, and providing patients with good knee joint function after surgery.

Keywords: Bone Plates; Comminution; Marginal fracture; Patellar fractures.

Fig. 1

Flow diagram of patient recruitment and retention

Fig. 2

Custom-made anchor-like plate made by modifying a T-shaped plate

Fig. 3

Intraoperative situation with the custom-made anchor-like plate in the treatment of lower patellar pole fracture. a A scalpel was used to cut a small opening in the patellar tendon at the lower pole. b The plate was passed through the small opening in the patellar tendon. c-d The plate was further shaped during the operation. e Additional cerclage of the combined steel wire. f After the hooping is pressurized, it is fixed with screws in turn

Fig. 4

A 53-year-old male suffered a fracture of the inferior pole of the left patella due to a fall. a-b Preoperative three-dimensional CT; c-d anteroposterior and lateral X-ray films of the knee joint of the affected limb on the second day after the operation; e-f One year after the operation, the patient’s anterior and lateral X-ray films of the knee joint; g-h functional appearance of the knee joint 1 year after the operation

Fig. 5

A 46-year-old female patient with distal patellar fracture. a-b Preoperative three-dimensional CT and lateral X-ray films of the knee joint; c-d anteroposterior and lateral X-ray films of the knee joint of the affected limb on the second day after the operation