Incidence and Risk Factors for Posterior Cruciate Ligament Avulsion during Cruciate Retaining Total Knee Arthroplasty

Abstract

During cruciate retaining (CR) total knee arthroplasty (TKA), the posterior cruciate ligament (PCL) may avulse at its insertion. The incidence of PCL avulsion fracture has not been previously studied. The aim of this study is to report on the incidence and clinical significance of intraoperative PCL avulsion during primary CR TKA and to identify potential risk factors. Our institutional joint registry was retrospectively reviewed for PCL avulsion occurring during CR TKA implanted between April 2008 and April 2016. Patient demographics, preoperative range of motion (ROM), complications, and revision rate were examined. A control group of 132 patients was used for comparison to identify potential risk factors. Forty-four of 2,457 patients (1.7%) suffered a PCL avulsion fracture during primary CR TKA. No intraoperative repair was performed and no postoperative weight bearing or ROM restrictions were implemented. There was no significant difference in BMI (p = 0.258), mean preoperative ROM (p = 0.763), or femoral and tibial component sizes (p = 0.3069, p = 0.1306) between groups. Logistic regression found female gender (p = 0.0254) to be the only statistically significant risk factor for PCL avulsion. The incidence of intraoperative PCL avulsion fracture during CR TKA is low (1.7%) and does not appear to affect postoperative ROM, subjective stability, or incidence of revision. Female gender was identified as the only patient factor that increased the risk of PCL avulsion fracture.

Good Clinical Middle-term Outcomes of the Reduction of Posterior Cruciate Ligament Avulsion Fracture in Cruciate Retaining Total Knee Arthroplasty

“…And, we found older patients and female gender may be the two risk factors of PCL avulsion fracture, we believe this may be due to more osteoporotic bones in women as older [10]; however, further research is needed before making a definitive statement.…”

“…Some studies have drawn attention that most PCL insertions may be destroyed during tibia cutting, and which raises questions about how much PCL actually saves in a CR TKA [18,[22][23][24][25][26]. Eric Kim et al [10] studied the incidence and risk factors of PCL avulsion during CR TKA, they found the incidence is 1.7% and female gender was the only risk factor. This study only compared pre and post-operative ROMs to support their conclusions, but did not mention how the postoperative clinical outcomes of unreduced the PCL avulsion fracture was.…”

“…However, whether reduce the PCL avulsion fracture or not in CR TKA is still controversial. One study analyzed the incidence of tibial side PCL avulsion fracture during primary CR TKA, and there was no attempt to reduce the avulsion fracture and achieved good postoperative results [10]. However, We think that if the avulsion fracture is not reduced, it may lead to the non-healing fracture, or even the knee instability and the failure of the operation.…”

A Surgical Reduction Technique for Posterior Cruciate Ligament Avulsion Fracture in Total Knee Arthroplasty: A Comparison Study

“…There are few studies that investigate patient-reported outcomes of PCL reduction in primary cruciateretaining TKA. Kim et al [7] showed that the incidence of tibial-sided PCL avulsion fractures was 1.7%, and female gender was the only risk factor. However, they did not reduce the PCL avulsion fracture and the function of PCL was assessed based on the comparison between the pre-and post-operative range of motion of the knee.…”

“…In this setting, whether to reduce the PCL avulsion fracture or not becomes a controversial issue. Kim et al [7] reported the incidence of tibial-sided PCL avulsion fracture during the primary cruciate-retaining TKA, but they did not attempt to reduce the fracture.…”