A Case Series of Fracture of PS Post in Posterior-stabilized Total Knee Arthroplasty and its Management Guidelines

Background: Late-onset instability in an otherwise well-functioning total knee arthroplasty (TKA) can be alarming for both patients and surgeons.A frequently overlooked yet treatable cause is fracture of the posterior-stabilized (PS) tibial post. Materials and methods:We present a series of 10 patients who developed new-onset instability several years post-primary PS-TKA.Each case was investigated using a standardized diagnostic algorithm involving clinical assessment, imaging, and infection workup.Additionally, a comprehensive literature review was conducted on tibial post fractures in PS-TKA.Results: Fractures occurred 6-13 years postoperatively, with instability and synovitis being the most common presenting features.All patients underwent a complete evaluation, including radionuclide scans to rule out loosening.Management involved isolated polyethylene insert exchange in two patients and full revision surgery in eight cases.Our literature review identified 72 documented cases of PS tibial post fractures.Factors such as implant design, polyethylene type, component malposition, and patient anatomy were commonly implicated.Conclusion: Tibial post-fracture is a rare but significant complication in PS-TKA.A high index of suspicion, appropriate diagnostic workup, and individualized surgical planning are critical.Isolated insert exchange may suffice in stable implants; however, full revision should be considered when loosening is suspected.Newer implant designs may mitigate this risk altogether.