Tension Band Wiring of Patella Fractures: Mid-Term Radiological and Clinical Results

Abstract

Objective: We aimed to share our radiological and clinical results with a mid-term follow-up on patella fractures treated with tension band wiring (TBW).
 Methods: Patients surgically treated with TBW for AO type 34-A1/C1/C2/C3 patella fractures between January 2013 and June 2021 at a level 1 trauma center were included. For radiological evaluation, radiographs obtained at the routine follow-up were analyzed for complications (such as nonunion, malunion, loss of reduction, malreduction, patella baja, elongated patella, implant failure), Insall-Salvati Index (ISI), and Patellar Morphology Ratio (PMR). The Knee Injury and Osteoarthritis Score (KOOS) was utilized for functional evaluation, which includes five subscales: pain, symptoms, activities of daily living (ADL), sports/recreation, and quality of life (QOL). The clinical assessment also included the range of motion (ROM), thigh circumference (TC), and complications such as implant irritation (II).
 Results: This study reviewed 42 eligible patients (10 females, 32 males) with a mean age of 42.6 ± 16.1 years and a mean follow-up of 35.4 ± 24.1 months. There were 28 patients (66.7%) with at least one complication (II: 66.7%, flexion deficit: 61.9%, malunion: 40.5%, elongated patella/patella baja: 16.7%). The reoperation rate was high at 69.1% due to the high implant removal rate for II. There were statistically significant differences between injured (I) and uninjured contralateral healthy knees (UI) in terms of mean KOOS subscale scores (symptoms: I: 72.3, UI: 89.8; pain: I: 70.4, UI: 89.4; ADL : I: 72.1, UI: 90; sports: I: 61.4, UI: 84.8; QOL: I: 67.9, UI: 86.2), mean flexion degrees (I: 126.2°, UI: 135.4°), mean ISI (I: 0.9, UI: 1.0), and mean PMR (I: 1.5, UI: 1.4) (all p < 0.01). There was no difference in mean extension degrees and TC (all p > 0.05). All fractures achieved union.
 Conclusion: Firstly, the mid-term clinical results of patellar fractures treated with TBW were significantly worse than the contralateral healthy knee; secondly, implant irritation, knee flexion deficit, malunion, and patella baja were the significant complications, and efforts should be made to manage these problems; thirdly, patellar fractures are susceptible to developing interesting cases of the elongated patella.