With increasing burden of revision hip arthroplasty, one of the major challenge is the management of bone loss associated with previous multiple surgeries. Proximal femoral replacement (PFR) has already been popularised for tumour surgeries. The inherent advantages of PFR over allograft –prosthesis system, which is the other option for addressing severe bone loss include, early weight bearing and avoidance of non-union and disease transmission. Our study explores PFR as a possible solution for the management of complex hip revisions. Thirty consecutive hips (29 patients) that underwent PFR between January 2009 and December 2015 were reviewed retrospectively for their clinical and radiological outcomes. The Stanmore METS system was used in all these patients. Mean age at the index surgery (PFR) was 72.69 years (range 50–89) with number of previous hip arthroplasties ranging from 1–5. At mean follow up of 32.27 months, there were no peri-prosthetic fractures and no mechanical failure of the implants. Clearance of infection was achieved in 80% of cases. There was 1 early failure due to intra-operative perforation of femoral canal needing further revision and two were revised for deep infection. Instability was noted in 26.7% (8) of the hips, of which, 87.5% (7) needed further revision with constrained sockets. Out of these 8 hips with instability, 5 had pre-operative infection. Deep infection was noted in 20% (6) of the hips, of which, 5 were primarily revised with PFR for septic loosening. However, further surgeries were essential for only 3 patients. One patient has symptomatic aseptic acetabular loosening and 1 had asymptomatic progressive femoral side loosening (lost to follow up). Severe proximal femoral bone loss in complex revision arthroplasties has necessitated the use of PFR prosthesis. Our study supports the fact that PFR is probably a mechanically viable option for complex revisions. Significant numbers of dislocations and infections could be attributed to the poor soft tissue envelope around the hip. Further surgical techniques in the form use of dual mobility cups and silver coated PFR implants need to be explored.
One of the major concerns of hinge knees have been reported in literature is mechanical failure. Failure in the form of component fracture (2–10%) and hinge dislocation/ failure are worrisome. In addition, higher risk of aseptic loosening with hinge knee prosthesis has been attributed to stress transfer at bone cement interface. Retrospective review of clinical and radiological results of 71 consecutive patients operated at single centre using Smiles hinge knee (Stanmore implants) between 2010 and 2014. Data was collected till the latest follow up. Mechanical failure due to any reason was considered as primary end point. Radiological evidence of aseptic loosening was considered to be one of the surrogate end points.Background
Methods
Distal femoral replacement is an operation long considered as salvage operation for neoplastic conditions. Outcomes of this procedure for difficult knee revisions with bone loss of distal femur have been sparsely reported. We present the early results of complex revision knee arthroplasty using distal femoral replacement implant, performed for severe osteolysis and bone loss. Retrospective review of clinic and radiological results of 25 consecutive patients operated at single centre between January 2010 and December 2014. All patients had single type of implant. All data was collected till the latest follow up. Re-revision for any reason was considered as primary end point. Mean age at surgery was 72.2 years (range 51 – 85 years). Average number of previous knee replacements was 2.28 (range 1 to 6). Most common indications were infection, aseptic loosening and peri-prosthetic fracture. Average follow up was 24.5 months (range: 3–63 months). 1 patient died 8 months post-op due to unrelated reasons. Re-revision rate was 2/25 (8%) during this period. One was re-revised for aseptic loosening and one was revised for peri-prosthetic fracture of femur. Two other peri-prosthetic fractures were managed by open reduction and internal fixation. All 3 peri-prosthetic fractures occurred with low energy trauma. It is noteworthy that there was no hinge or mechanical failures of the implant. Peri-prosthetic fracture in 12% of patients in this series is of concern. There are no similar studies to compare this data with. The length of the stem, type of fixation of the stem, weight of the distal femoral component of implant can be postulated as factors contributing to risk of peri-prosthetic fracture.
Current analysis of unicondylar knee replacements (UKR) by national registries is based on the pooled results of medial and lateral implants. Using data from the National Joint Registry for England and Wales (NJR) we aimed to determine the proportion of lateral UKR implanted, their survival and reason for failure in comparison to medial UKR. By combining information on the side of operation with component details held on the NJR we were able to determine implant laterality (medial vs. lateral) for 32,847 of the 35,624 (92%) UKR registered before December 2010. Kaplan Meier plots, Life tables and Cox' proportion hazards were used to compare the risk of failure for lateral and medial UKRs after adjustment for patient and implant covariates.Background
Methods
Following in-depth analysis of the market leading brand combinations in which we identified implant influences on risk of revision, we compared revision in patients implanted with different categories of hip replacement in order to find implant with the lowest revision risk, once known flawed options were removed. All patients with osteoarthritis who underwent a hip replacement (2003–2010) using an Exeter-Contemporary (cemented), Corail-Pinnacle (cementless), Exeter-Trident (Hybrid) or a Birmingham Hip resurfacing (BHR) were initially included within the analysis. Operations involving factors that were significant predictors of revision were excluded. Cox proportional hazard models were then used to assess the relative risk of revision for a category of implant (compared with cemented), after adjustment for patient covariates.Introduction
Methods
We aim to assess the functional outcome, patient perceived satisfaction and implant survival at a mean follow up of 13[10–16] years following revision knee replacement. Between 1995 and 2001, 243 revision knee replacements were performed in 230 patients using Endolink [Link, Hamburg] or TC3 [Depuy, Leeds] prosthesis at Wrightington hospital, Wrightington, were consented to take part in this study. Data was collected prospectively which includes complications and functional assessment by Oxford knee score, WOMAC, HSS, UCLA, SF12 scores, and patient satisfaction questioner. The scores were obtained pre-operatively and post-operatively at 1 year, 5 years and at the latest follow-up. The mean age was 69 yrs, 51% were males, TC3 prosthesis as used in 175 and Endolink in 68, the revision was for Infection in 71[29%], 53 patients had intra-operative positive culture, 35 had 2 stage revision.Introduction
Patients and Methods
We aim to assess the functional outcome, patient satisfaction and implant survival at a mean follow up of 13[10–16] years following revision for infected total knee replacement. Between 1995 and 2001, 71 revision knee replacements were performed for infection, at Wrightington hospital, Wrightington. Data was collected prospectively which includes intra-operative cultures, complications and functional assessment by Oxford knee score, WOMAC, HSS, UCLA, SF12 scores, and patient satisfaction questioner. The scores were obtained pre-operatively and post-operatively at 1 year, 5 years and at the latest follow-up. Mean age was 69 yrs, 70% were Females, 31[44%] had 2 stage revisions and intra-operative culture was positive in 53 patients. Most common organism was staphylococcus aureus in 30% and staphylococcus epidermides in 18%.Introduction
Patients and Methods
We have assessed the bone cuts achieved at surgery compared to the planned cuts produced during computer assisted surgery (CAS) using a CT free navigation system. In addition, two groups of matched patients were compared to assess the post-operative mechanical alignment achieved: 14 patients received a LCS total knee replacement (TKR) using the VectorVision module and 14 received a TKR using a conventional method of extramedullary alignment jigs The deviation in each plane (valgus-varus, flexion-extension and proximal-distal) was calculated. For the tibia the mean deviation in the coronal plane was 0.21 degrees of Varus (SD = 1.37) and in the sagittal plane was 1.29 degrees of flexion (SD = 3.73) and 0.24 mm of resection distal to the anticipated cut (SD = 2.14). For the femur the mean deviation in the coronal plane was 0.88 degrees (SD = 2.2) of valgus and in the sagittal plane the mean deviation was 0.3 degrees (SD = 2.91) of extension. In the transverse plane there was a mean deviation of 0.07 degrees (SD = 1.57) of external rotation. There was mean deviation of 2.33 mm of proximal resection (SD = 2.9) and 1.05 mm of anterior shift (SD = 2.81). On comparing the two groups, no statistically significant differences were found for the angles between the femoral component and the femoral mechanical axis, the tibial component and the tibial mechanical axis, the femoral and tibial mechanical axis and the femoral and tibial anatomical axis. We have demonstrated variation in the true bone cuts obtained using computer assisted surgery from those suggested by the software and have not demonstrated significant improvement in post-operative alignment. Justification for the extra cost, time and morbidity associated with this technology must be provided in the form of improved clinical outcomes in the future.
