Owen J Diamond1, Lisa Howard2, Bassam Masri3. 1. University of British Columbia, Department of Orthopaedics, Adult Hip and Knee Reconstruction Service, Gordon & Leslie Diamond Health Care Centre, 3rd Floor, 2775 Laurel Street, Vancouver, BC V5Z 1M9, Canada. Electronic address: diamondo@hss.edu. 2. University of British Columbia, Department of Orthopaedics, Adult Hip and Knee Reconstruction Service, Gordon & Leslie Diamond Health Care Centre, 3rd Floor, 2775 Laurel Street, Vancouver, BC V5Z 1M9, Canada. 3. University of British Columbia, Department of Orthopaedics, Adult Hip and Knee Reconstruction Service, Gordon & Leslie Diamond Health Care Centre, 3rd Floor, 2775 Laurel Street, Vancouver, BC V5Z 1M9, Canada. Electronic address: bassam.masri@vch.ca.
Abstract
BACKGROUND: Fracture of a polyethylene tibial post after a posterior stabilized total knee arthroplasty (PS-TKA) is an uncommon but severe complication. We report five cases of non-traumatic fracture of a tibial polyethylene post that occurred with Prolong highly cross-linked polyethylene with the NexGen LPS-Flex total knee prosthesis. METHODS: A Joint Reconstruction database for a high volume arthroplasty unit was used to identify all cases of revision of Prolong polyethylene used in PS-TKA. Five cases were identified as being revised because of a broken tibial post. RESULTS: All five cases presented with a combination of sudden and increasing pain, instability and giving way, in previously well-functioning TKAs. There was no history of trauma or precipitating incident. Mean time from primary TKA to presentation and diagnosis of post fracture was 67.7 months (range 24-108). All five cases were successfully treated by revision, in the form of a liner exchange to a standard ultra-high molecular weight polyethylene (UHMWPE) bearing of the same thickness. The five cases occurred from a consecutive series of 955 total PS-TKAs with Prolong. This gives a conservative estimate of the frequency of this complication of 0.52%. This would give a risk of a tibial post fracture in approximately one in every 200 TKAs with this specific implant and bearing combination. CONCLUSIONS: To our knowledge, this is the first report of a non-traumatic fracture to the tibial post with this bearing type. We would advocate against the routine use of Prolong highly crosslinked polyethylene in PS-TKA.
BACKGROUND:Fracture of a polyethylene tibial post after a posterior stabilized total knee arthroplasty (PS-TKA) is an uncommon but severe complication. We report five cases of non-traumatic fracture of a tibial polyethylene post that occurred with Prolong highly cross-linked polyethylene with the NexGen LPS-Flex total knee prosthesis. METHODS: A Joint Reconstruction database for a high volume arthroplasty unit was used to identify all cases of revision of Prolong polyethylene used in PS-TKA. Five cases were identified as being revised because of a broken tibial post. RESULTS: All five cases presented with a combination of sudden and increasing pain, instability and giving way, in previously well-functioning TKAs. There was no history of trauma or precipitating incident. Mean time from primary TKA to presentation and diagnosis of post fracture was 67.7 months (range 24-108). All five cases were successfully treated by revision, in the form of a liner exchange to a standard ultra-high molecular weight polyethylene (UHMWPE) bearing of the same thickness. The five cases occurred from a consecutive series of 955 total PS-TKAs with Prolong. This gives a conservative estimate of the frequency of this complication of 0.52%. This would give a risk of a tibial post fracture in approximately one in every 200 TKAs with this specific implant and bearing combination. CONCLUSIONS: To our knowledge, this is the first report of a non-traumatic fracture to the tibial post with this bearing type. We would advocate against the routine use of Prolong highly crosslinked polyethylene in PS-TKA.
Authors: Ioannis Gkiatas; Theofilos Karasavvidis; Abhinav K Sharma; William Xiang; Michael-Alexander Malahias; Brian P Chalmers; Peter K Sculco Journal: Arch Orthop Trauma Surg Date: 2021-04-13 Impact factor: 3.067
Authors: David H Dejour; Jacobus H Müller; Mo Saffarini; Michel Timoteo; Pierre Chambat; Gerard Deschamps; Michel P Bonnin Journal: Knee Surg Sports Traumatol Arthrosc Date: 2021-03-04 Impact factor: 4.342