ObjectivesThis systematic review and meta-analysis was conducted to determine the mid- to long-term clinical outcomes for a medial-pivot total knee replacement (TKR) system. The objectives were to synthesise available survivorship, Knee Society Scores (KSS), and reasons for revision for this system.MethodsA systematic search was conducted of two online databases to identify sources of survivorship, KSS, and reasons for revision. Survivorship results were compared with values in the National Joint Registry of England, Wales, and Northern Ireland (NJR).ResultsA total of eight studies that included data for 1146 TKRs performed in six countries satisfied the inclusion/exclusion criteria. Pooled component survivorship estimates were 99.2% (95% CI, 97.7 to 99.7) and 97.6% (95% CI, 95.8 to 98.6) at five and eight years, respectively. Survivorship was similar or better when compared with rates reported for all cemented TKRs combined in the NJR and was significantly better than some insert types at mid-term intervals. The weighted mean post-operative KSS was 87.9 (73.2 to 94.2), in the excellent range. Similar cumulative revision rates and KSS were reported at centres in the United States, Europe, and Asia.ConclusionsThe subject system was associated with survivorship and KSS similar or better than that reported for other TKR systems.Cite this article: Bone Joint Res 2014;3:297–304

Background Various surface coatings have been developed over the past decades to enhance fixation of cementless total knee arthroplasty (TKA). BIOFOAM® (MicroPort Orthopedics Inc., Arlington, TN, USA) is a novel cancellous titanium surface coating intended to increase both initial and long-term fixation. The purpose of this study was to investigate the early functional and radiographic outcomes of this coating used in a TKA application.Materials and methodsOne hundred and four (104) primary TKAs in 85 subjects using BIOFOAM-coated tibial components were prospectively enrolled at four centers. Subjects were evaluated using Knee Society Scores and radiographic analysis at a minimum follow-up of 24 months.ResultsKnee Society Scores and flexion were all significantly improved at final follow-up compared to baseline. Radiographic analyses were satisfactory, with no progressive radiolucencies and only a single subject presenting with a radiolucency surrounding a tibial component. There were two revisions in the cohort: one for instability following a ruptured lateral collateral ligament and one for recurrent tibial insert dislocation.ConclusionsThis is the first study to report clinical outcomes associated with the BIOFOAM coating used in a cementless TKA application. Early functional scores and radiographic analyses are promising, but further investigations are needed to confirm long-term clinical success with these components.

No abstract

No abstract

Current in vitro testing methodologies remain limited in the ability to explore spinal mechanics. The gold standard of flexibility testing has traditionally focused only on evaluating rotational components of motion within a motion segment unit (MSU). While such data may be applied towards evaluation of the Center of Rotation (CoR) of a joint, many systems lack the needed sensitivity. The result is that there is currently no consensus on the location of the CoR of the spine. Further, very limited data or insight can be gathered as to the precise kinematic or dynamic state of the MSU, the influence of surgically implanted motion restoration devices, or the influence of subtle changes to an implanted device.