Persistent patellofemoral symptoms can cause patient dissatisfaction after Total Knee Arthroplasty (TKA). The aim of this retrospective study was to evaluate patellar tracking and patient outcomes utilizing two implant designs in TKA. Medical records and radiographs of two groups of 100 consecutive patients each were reviewed. All patients underwent posterior stabilized TKA by a single surgeon; using the same operative technique but two different implant designs (Group 1: Asymmetric femoral component with deep congruent trochlear groove and Group 2: Asymmetric femoral component with shallow trochlear groove). Data was collected on demographic characteristics, patellar tilt, displacement, prosthesis-bone angle, HSS Patella Score, Knee Society Knee and Function Score. Patellar tilt more than 5° was considered significant. Statistical analysis was done using the SPSS v.16.0.3 software (SPSS, Inc., Chicago, IL). Patients' age and sex were equivalent in the two groups (p>0.57). Median follow up was 2.2 years. Pre-operative incidence of patellar tilt was similar in both groups (18% vs. 17%). After surgery, these values changed to 30% and 77% respectively. This was statistically significant (p<0.001). The Knee Society Knee and Function Score improved significantly in both groups, however the improvement in the function score was significantly greater in the first group (p=0.001). The improvement in Knee Society Knee Score (50.24 and 48.08; p= 0.18) and post-operative HSS Score (93 vs. 91; p=0.19) were not statistically significant. Our findings suggest that despite using the same operative technique, patellar tracking was significantly different between the two groups, a finding most likely attributable to the design of the femoral component. Whether the difference in patellar maltracking will affect long-term survival of the patellar component remains to be seen.
Although Total Knee Arthroplasty (TKA) has been shown to correct abnormal frontal plane knee biomechanics, little is known about this effect beyond 6 months. The purpose of this study was to compare sequentially the knee adduction moment during level-walking before and after TKA in varus knees. We hypothesized that adduction moment would diminish after TKA proportionate to the tibio-femoral realignment in degrees. Fifteen patients (17 TKA's) with varus knees were prospectively enrolled and gait analysis performed prior to, 6 months and 1 year following TKA. Reflective markers were placed on the lower extremity and motion data collected using six infrared cameras (Qtrac, Qualysis). Ground reaction forces were recorded with a multicomponent force plate (Kistler). A repeated-measures ANOVA was used to compare changes in the peak adduction moment and peak dynamic varus angle over time.Introduction
Methods
Studies have documented encouraging results with the use of fluted, tapered, modular, titanium stems in revision hip arthroplasty with bone loss. However, radiographic signs of osseointegration and patterns of reconstitution have not been previously categorized. 64 consecutive hips with index femoral revision using a particular stem of this design formed the study cohort. Serial radiographs were retrospectively reviewed by an independent observer. Bone loss was determined by Paprosky's classification. Osseointegration was assessed by a slight modification of the criteria of Engh et al. Femoral restoration was classified according to Kolstad et al. Pain and function was documented using Harris Hip Score (HHS).Introduction
Materials and Methods
It is not uncommon to encounter patients with atypical hip or lower extremity pain, ill-defined clinico-radiological features and concomitant hip and lumbar spine arthritis. It has been hypothesized that an anaesthetic hip arthrogram can help identify the source of pain in these cases. The purpose of this study is to analyze our experience with this technique in order to verify its accuracy. We undertook a retrospective analysis of 204 patients who underwent a hip anesthetic-steroid arthrogram for diagnostic purposes matching our inclusion criteria. Patient charts were scrutinized carefully for outcomes of arthrogram and treatment. Harris Hip Score was used to quantify outcome.Introduction
Methods
Implant related hypersensitivity is an infrequent complication after total knee replacement. It remains a relatively unpredictable and poorly understood cause of failure of an implant. We present a report of five patients who presented with persistent hypertrophic synovitis after total knee replacement using a cobalt chrome component. Extensive preoperative and intraoperative attempts ruled out infection as a cause of symptoms. The knees had good ligamentous balance and were well aligned and fixed. The clinical condition improved after revision to a zirconium femoral and titanium metal backed tibial components. Intraoperative histopathology revealed thickened synovium with a predominantly monocellular (lymphocytic or histiocytic) response. Where infection has been excluded as a cause of persistent pain and swelling, consideration should be given to metal allergy as a cause of failure in primary knee replacement surgery.
