Deformity of knee joint causes deviation of mechanical axis in the coronal plane, and the mechanical axis deviation also could adversely affect biomechanics of the ankle joint as well as the knee joint. Particularly, most of the patients undergoing total knee arthroplasty (TKA) have significant preoperative varus malalignment which would be corrected after TKA, the patients also may have significant changes of ankle joint characteristics after the surgery. This study aimed 1) to examine the prevalence of coexisting ankle osteoarthritis (OA) in the patients undergoing TKA due to varus knee OA and to determine whether the patients with coexisting ankle OA have more varus malalignment, and 2) to evaluate the changes of radiographic parameters for ankle joint before and 4 years after TKA. We evaluated 153 knees in 86 patients with varus knee OA who underwent primary TKA. With use of standing whole-limb anteroposterior radiographs and ankle radiographs before and 4 years after TKRA, we assessed prevalence of coexisting ankle OA in the patients before TKA and analyzed the changes of four radiographic parameters before and after TKA including 1) the mechanical tibiofemoral angle (negative value = varus), 2) the ankle joint orientation relative to the ground (positive value = sloping down laterally), 3) ankle joint space, and 4) medial clear space.Introduction
Methods
Even a number of studies have reported clinical outcomes after revision total knee arthroplasty (revision TKA), little information is still available on whether outcomes of patients undergoing a revision TKA as a second stage procedure because of infected TKA are poorer than those of the patients undergoing a single-stage revision TKA because of non-infectious causes. In addition, use of various revision prostheses in most previous studies may limit solid interpretation of the outcomes after revision TKA. This study sought to determine whether outcomes in patients undergoing revision TKA due to infected TKA would be different from those in patients undergoing revision TKA due to non-infectious causes. We assessed 71 cases undergoing revision TKAs with use of a same revision system (Scorpio TS®, Stryker, Mahwah, NJ) from October 1999 to February 2012. All patients followed more than two years and mean follow-up period was 67 months (range: 24 – 168 months). Of them, thirty five patients underwent revisions due to infected TKA (group for infected TKA) while 36 patients due to non-infectious causes including loosening, wear, and/or instability (group for non-infected TKA). All patients in the group for infected TKA underwent two-stage revision surgeries while all patients in the group for non-infected TKA single stage revision surgeries. Comparative variables between two groups were preoperative range of motion (ROM) and American knee society (AKS) scores, postoperative ROM and AKS scores assessed at latest follow-up, amount of bone loss and requirement of stem assessed during the surgeries, and survival rate.Introduction
Materials and Methods
Total knee arthroplasty (TKA) is a proven treatment method for advanced knee arthritis in terms of pain relief, function restoration, and quality-of-life improvement. The TKA use has increased significantly over the past decade and the growing rate is more prominent in Asian countries. Thus, the revision TKA may also increase in recent days, which represents a burden to the national health care system. To the best of our knowledge, little information is currently available regarding the incidence and related factors of revision TKA in Asian countries on the basis of nationwide database. This study sought to find the incidence of revision TKA and related factors in South Korea using national database from 2007 to 2012. Data collected by the Health Insurance Review Agency of Korea, from 260,068 TKA patients between 2007 and 2012, were used to estimate the incidence of revision TKA according to age group, gender and hospital TKA and manufacturer prosthesis volume (i.e., the number of TKA procedures carried out at a given hospital, and the number of procedures performed using a given manufacturer's prosthesis, respectively). Age group and hospital and manufacturer volumes were categorized into three groups and TKA incidence rates were computed for groups stratified according to age, gender and hospital and manufacturer volumes.Introduction
Material and Method
A novel bipolar cooled radiofrequency ablation probe, optimised for bone metastases applications, is shown in two preclinical models to offer a safe and minimally invasive treatment option that can ablate large tissue volumes and preserve the regenerative ability of bone. Use of radiofrequency ablation (RFA) in treating of skeletal metastases has been rising, yet its impact on bone tissue is poorly understood. 2–11 RF treatment induces frictional heating and effectively necrotises tissue in a local and minimally invasive manner.1 Bipolar cooled RF (BCRF) is a significant improvement to conventional RF whereby larger regions can be safely treated, protecting sensitive neighbouring tissues from thermal effects. This study aimed to evaluate the safety and feasibility of a novel bipolar RFA probe to create large contained lesions within healthy pig vertebrae and its determine its effects on bone and tumour cells in a rabbit long bone tumour model.Summary
Introduction
We checked intraoperative patellar tracking with both ‘towel clip technique’ and the ‘no thumb technique’ on 354 patients (571 knees) who underwent primary total knee arthroplasty to decide whether to do or not to do lateral retinacular release. All surgical procedures consisted of medial parapatellar arthrotomy and patellar resurfacing. Patellar tracking was assessed under pneumatic tourniquette with the no thumb technique first and reevaluated with the towel clip technique. The tracking was graded as total contact, good contact, lateral contact, and subluxation. The knees graded as total or good contact with the no thumb technique were classified into group A; those graded lateral contact or subluxation by the no thumb technique but total or good contact by the towel clip technique were classified into group B; and those graded lateral contact or subluxation by both techniques were classified into group C, in which lateral releases were performed. We classified 371, 148, and 52 knees into groups A, B, and C respectively. Patellar lateral tilting in the Merchant view was reviewed preoperatively and 2 weeks, 6 weeks, 6 months, and 1 year postoperatively. There were no statistical differences on postoperative patellar tilting among the groups. Assessment of the patellar tracking using only the no thumb technique may overestimate the need for lateral retinacular release. The use of the no thumb technique as a screening test, and reevaluation with the towel clip technique, may reduce unnecessary lateral retinacular release.
We analyzed the causes of 113 revision total knee arthroplasties in 84 patients between December 1996 and June 2008. Patient history, medical record and radiographs were reviewed to detect the main cause of failure of primary total knee arthroplasty. The causes of revision total knee arthroplasty were as follows: 44 infections (38.9 %), 34 loosenings (30.1%), 22 polyethylene wears or breakages (19.5%), 5 stiffness (4.4%), 4 polyethylene dislocations (3.5%), 2 patellar dislocations (1.8%), 1 patellar component failure and 1 instability (0.9%, each). The mean interval from the index operation to the revision surgery was 59 months (1 month-20 years). Infection was the most common causes of revision TKA and followed by loosening, wear or breakage of polyethylene, stiff knee, dislocation of polyethylene and so on.
