Treatment of displaced fractures of the patella: Tension band wiring technique with the one-end or both-ends K-wire bending fixation method

Predictors of postoperative complications of tension band wiring techniques for patella fracture: A retrospective multicenter (TRON group) study

OBJECTIVE

The relationship between postoperative complications and operative techniques of tension band wiring (TBW) is not well studied. We aimed to evaluate the incidence of implant breakage, implant migration, and loss of reduction in patellar fractures treated with TBW and identify radiographic factors associated with these postoperative complications.

METHODS

This multicenter (named, TRON group) retrospective study included 224 patients who underwent open reduction and internal fixation of patella fractures using TBW from January 2016 to December 2020. Radiographic findings were evaluated by experienced orthopedic surgeons, and radiographic outcomes were assessed for K-wire migration, implant breakage, and loss of reduction. Logistic regression analysis was performed to identify radiographic factors associated with postoperative complications.

RESULTS

Implant migration occurred in 44 cases (19.6%), with bending of a single K-wire end identified as a significant risk factor (OR: 12.90; 95% CI: 4.99-33.30; P < 0.001). Implant breakage occurred in 43 cases (19.2%), with a large patella-tension band ratio (OR: 291.0; 95% CI: 19.60-4330; P < 0.001) and a wide distance between K-wires (OR: 1.15; 95% CI: 1.060-1.250; P = 0.001) identified as significant risk factors. Loss of reduction occurred in 5 cases (2.0%), but no significant risk factors were identified.

CONCLUSION

This study highlights the importance of bending both ends of the K-wires and proper placement of the tension band and K-wires in reducing postoperative complications in patellar fractures treated with TBW. Further research is needed to better understand the risk factors associated with loss of reduction.

Surgical treatment of inferior pole fractures of the patella: a systematic review

PURPOSE

This study aimed to comprehensively review the existing evidence concerning surgical treatment of inferior pole fractures of the patella and to report the outcomes and complications of different fixation techniques.

METHOD

This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches of PubMed, Scopus, and Web of Science were conducted in March 2023. Studies were screened against predecided inclusion and exclusion criteria. The extracted data included fracture characteristics, surgical techniques, and radiographic and functional outcomes. The Methodological Index for Non-Randomized Studies (MINORS) quality assessment tool was used to assess the eligible literature. The primary outcome was postoperative range of motion of different surgical methods, and the secondary outcomes were other clinical results and complications.

RESULTS

A total of 42 studies satisfied all the inclusion criteria and were deemed suitable for review. Fourteen case-control studies and 28 case series were selected, for a total of 1382 patients with a mean age of 51.0 years (range = 11-90). The follow-up period ranged from 6 to 300 months. The surgical techniques were categorized based on the device used as follows: (1) rigid fixation device; (2) tensile fixation device; (3) mixed device; and (4) extra-patella device.

CONCLUSION

Regarding the outcomes following surgical treatment of inferior pole fractures of the patella, the postoperative range of motion (ROM) of each technique ranged from 120° to 135°, with the exception of that involving the patellotibial wire which had poorer outcomes. The lowest functional score was also found in those using the patellotibial wire. Complications after surgery are rare, but approximately half of the patients required additional surgery for implant removal, particularly those whose initial surgery involved rigid fixation devices. It's worth noting that bony fragment excision is no longer recommended, and the combined use of multiple surgical devices is now more common.

Clinical application of Kirschner wires combined with 5-Ethibond fixation for patella fractures

Background

Patella fractures that require surgery are conventionally treated using Kirschner wires (K-wires) and stainless steel wires. In recent years, the nonabsorbable polyester has been reported to have excellent outcomes clinically. Therefore, the goal of our study was to evaluate the effects of Kirschner wires combined with 5-Ethibond on treating patellar fractures.

Methods

From July 2018 to January 2022, 22 patella fracture patients were treated with Kirschner wires combined with 5-Ethibond. Radiographs of the knees were used to evaluate fracture healing and hardware complications. The clinical results were evaluated through the functional score, knee joint range of motion (ROM), and Bostman patella fracture functional score.

Results

The average age of patients was 57.4 ± 11.9 (range 33-74) years. The mean follow-up time was 15.2 ± 7.6 (range 4-36) months. The mean operation time was 56.8 ± 8.7 (range 45-80) min. The entire patients had bony union at an average of 10.5 ± 1.9 (range 8-14) weeks. At the final follow-up, the mean range of postoperative ROM was 123.4° ± 14.6° (range 95°-140°), and the functional score was 28.7 ± 1.2 (range 26-30) points. No patient exhibited internal fixation failure, and no symptomatic implants or skin complications were recorded.

Conclusions

The fixation approach using K-wires combined with 5-Ethibond has a lower complication rate and delivers superior clinical results. This research reveals that such technology is a safe and prospective substitute for conventional metal fixation approaches.