Bone loss in the proximal tibia and distal femur
is frequently encountered in revision knee replacement surgery.
The various options for dealing with this depend on the extent of
any bone loss. We present our results with the use of cementless
metaphyseal metal sleeves in 103 patients (104 knees) with a mean
follow-up of 43 months (30 to 65). At final follow-up, sleeves in
102 knees had good osseointegration. Two tibial sleeves were revised
for loosening, possibly due to infection. The average pre-operative Oxford Knee Score was 23 (11 to 36)
and this improved to 32 (15 to 46) post-operatively. These early
results encourage us to continue with the technique and monitor
the outcomes in the long term. Cite this article:
The purpose of this investigation was to determine the relationship between height, weight, and sex with implant size in total knee arthroplasty (TKA) using a multivariate linear regression model and a Bayesian model. A retrospective review of an institutional registry was performed of primary TKAs performed between January 2005 and December 2016. Patient demographics including patient age, sex, height, weight, and body mass index (BMI) were obtained from registry and medical record review. In total, 8,100 primary TKAs were included. The mean age was 67.3 years (SD 9.5) with a mean BMI of 30.4 kg/m2 (SD 6.3). The TKAs were randomly split into a training cohort (n = 4,022) and a testing cohort (n = 4,078). A multivariate linear regression model was created on the training cohort and then applied to the testing cohort . A Bayesian model was created based on the frequencies of implant sizes in the training cohort. The model was then applied to the testing cohort to determine the accuracy of the model at 1%, 5%, and 10% tolerance of inaccuracy.Aims
Methods
Varus-valgus constrained (VVC) implants are often used during revision total knee arthroplasty (TKA) to gain coronal plane stability. However, the increased mechanical torque applied to the bone-cement interface theoretically increases the risk of aseptic loosening. We assessed mid-term survivorship, complications, and clinical outcomes of a fixed-bearing VVC device in revision TKAs. A total of 416 consecutive revision TKAs (398 patients) were performed at our institution using a single fixed-bearing VVC TKA from 2007 to 2015. Mean age was 64 years (33 to 88) with 50% male (199). Index revision TKA diagnoses were: instability (n = 122, 29%), aseptic loosening (n = 105, 25%), and prosthetic joint infection (PJI) (n = 97, 23%). All devices were cemented on the epiphyseal surfaces. Femoral stems were used in 97% (n = 402) of cases, tibial stems in 95% (n = 394) of cases; all were cemented. In total, 93% (n = 389) of cases required a stemmed femoral and tibial component. Femoral cones were used in 29%, and tibial cones in 40%. Survivorship was assessed via competing risk analysis; clinical outcomes were determined using Knee Society Scores (KSSs) and range of movement (ROM). Mean follow-up was four years (2 to 10).Aims
Methods
Little is known about the relative outcomes of revision of unicompartmental
knee arthroplasty (UKA) and high tibial osteotomy (HTO) to total
knee arthroplasty (TKA). The aim of this study is to compare the
outcomes of revision surgery for the two procedures in terms of
complications, re-revision and patient-reported outcome measures (PROMs)
at a minimum of two years follow-up. This study was a retrospective review of data from an institutional
arthroplasty registry for cases performed between 2001 and 2014.
A total of 292 patients were identified, of which 217 had a revision
of HTO to TKA, and 75 had revision of UKA to TKA. While mean follow-up
was longer for the HTO group compared with the UKA group, patient
demographics (age, body mass index and Charlson co-morbidity index)
and PROMs (Short Form-36, Oxford Knee Score, Knee Society Score,
both objective and functional) were similar in the two groups prior
to revision surgery. Outcomes included the rate of complications
and
re-operation, PROMS and patient-reported satisfaction at six months
and two years post-operatively. We also compared the duration of
surgery and the need for revision implants in the two groups. Aims
Patients and Methods
We reviewed the rate of revision of unicompartmental knee replacements (UKR) from the New Zealand Joint Registry between 1999 and 2008. There were 4284 UKRs, of which 236 required revision, 205 to a total knee replacement (U2T) and 31 to a further unicompartmental knee replacement (U2U). We used these data to establish whether the survival and functional outcome for revised UKRs were comparable with those of primary total knee replacement (TKR). The rate of revision for the U2T cohort was four times higher than that for a primary TKR (1.97 The poor outcome of a UKR converted to a primary TKR compared with a primary TKR should contra-indicate the use of a UKR as a more conservative procedure in the younger patient.
