This study was performed to investigate the failure mechanism of one specific hip arthroplasty cup design that has shown a high clinical failure rate. The aim of this study was to identify general design problems of this polyethylene inlay. 55 consecutive retrievals of a cementless screw ring (Mecron) were collected. In any case a 32 mm ceramic head was used. All implants failed due to aseptic loosening. The follow-up of the implants was 3 to 16 years. We recorded backside wear, fatigue of the polyethylene at the flanges on the outer rim and at the cup opening (32 mm inner diameter). To assess the deformation of the inlay, the smallest and the median diameter of the cup opening were measured using a 3 dimensional coordinate measuring machine (Multisensor, Mahr, Germany).Introduction
Material and Methods
This study was performed to evaluate clinical and radiographic outcomes of Hip Resurfacing Arthroplasty for treatment of haemophilic hip arthropathy. Between 2002 and 2013, 17 cases of hip resurfacing arthroplasties were performed in 16 haemophilic patients (13 cases of haemophilia A, 2 cases of haemophilia B, 2 cases of von Willebrand disease). The average age of the patients was 32.5(range: 18∼52) years. The average follow up period from the operation was 6.3 (range: 2∼13) years. In this study, the subjects that completed follow-up were composed of 5 cases composed of patients who were treated with Conserve plus® hip resurfacing system, 5 cases composed of patients who were treated with Durom® hip resurfacing system, 4 cases who were treated with ASR® hip resurfacing system, and 3 cases who were treated with Birmingham® hip resurfacing system. The Modified Harris hip score, the range of motion of the hip joint, perioperative coagulation factor requirements and complications associated with bleeding were evaluated as part of the clinical assessment. For the radiographic assessment, fixation of component, presence of femoral neck fracture, osteolysis, loosening and other complications were evaluated.Purpose
Material & Method
Mechanically aligned total knee arthroplasty(TKA) relies on restoring the hip-knee-ankle angle of the limb to neutral or as close to a straight line as possible. This principle is based on studies that suggest limb and knee alignment is related long term survival and wear. For that cause, there has been recent attention concerning computer-assisted TKA and robot is also one of the most helpful instruments for restoring neutral alignment as known. But many reported data have shown that 20% to 25% of patients with mechanically aligned TKA are dissatisfied. Accordingly, kinematically aligned TKA was implemented as an alternative alignment strategy with the goal of reducing prevalence of unexplained pain, stiffness, and instability and improving the rate of recovery, kinematics, and contact forces. So, we want to report our extremely early experience of robot-assisted TKA planned by kinematic method. This study evaluated the very short term results (6 weeks follow up) after robot-assisted TKA aligned kinematically. 50 knees in 36 patients, who could be followed up more than 6 weeks after surgery from December 2014 to January 2015, were evaluated prospectively. The diagnosis was primary osteoarthritis in all cases. The operation was performed with ROBODOC (ISS Inc., CA, USA) along with the ORTHODOC (ISS Inc., CA, USA) planning computer. The cutting plan was made by single radius femoral component concept, each femoral condyles shape-matched method along the transverse axis using multi-channel CT and MRI to place the implant along the patient's premorbid joint line. Radiographic measurements were made from long bone scanograms. Clinical outcomes and motion were measured preoperatively and 6 weeks postoperatively.Introduction
Materials and Methods
The “Golden Patient” is suitability worked up to be the first theatre case of the day; the aim being to improve theatre efficiency. A previous audit of theatre activity demonstrated that the average knife to skin time being achieved across 3 daily trauma lists was 10.12. Over 2-months we introduced a Golden Patient Pathway and completed the audit cycle. The pathway involved a checklist to ensure the completion of essential clinical tasks for each designated golden patient. Activities from 74 trauma theatre cases were reviewed. 47 golden patients remained first whilst 27 were deferred for reasons including non-suitability for golden patient status and emergent cases given clinical priority. The average theatre call time was 24 minutes earlier and the average knife-to-skin time was 15 minutes earlier than non-golden patients during the re-audit. However, when compared to the initial audit the knife-to-skin time had only improved by 3 minutes. Reasons effecting theatre efficiency are multifactorial and other organisational changes had occurred between the audits. This study demonstrates that while the Golden Patient Pathway can improve theatre start times it is not the whole solution. Communication, anaesthetic job plans, portering arrangements, equipment storage and theatre staffing also need to be reviewed.
The success of total knee arthroplasty depends on many factors, including the preoperative condition of the patient, the design and materials of the components and surgical techniques. It is important to position the femoral and tibial components accurately and to balance the soft tissues. Malpositioning of the component can lead to failures due to aseptic loosening, instability, polyethylene wear and dislocation of the patella. In order to improve post-operative alignment, computer-aid systems have been developed for total knee arthroplasty. Many clinical and experimental studies of these systems have shown that the accuracy of implanted components can be improved in spite of the increase in costs and operating time. This may not, however, improve the outcome in the short-term. Restoration of the normal mechanical axis of the knee and balancing of the surrounding soft tissues have been shown to have an important bearing on the final outcome of knee replacement operations. In severely deformed knees, whether varus or valgus, these goals may be difficult to achieve. We compared the radiologic results of the mechanical axis and implant position of Total Knee Arthroplasty using a robot-assisted method with conventional manually implanted method in severe varus deformed knee. A data set of 50 consecutive cases that were performed from April 2007 to December 2010 using the robot assisted TKA(Group A) were compared with a data set of 50 consecutive cases from the same period that were done using conventional manual TKA(Group B). All cases had a preoperative mechanical varus deformity >15° and one brand of implant was used on all cases. The diagnosis was primary osteoarthritis in all knees. The operations were performed by one-senior author with the same robot system, ROBODOC (ISS Inc., CA, USA) along with the ORTHODOC (ISS Inc., CA, USA) planning computer. (See Figure 1.) The radiological evaluations included mechanical axis, implant position (α,β,γ,δ angle) according to the system of American Knee Society.Introduction
Materials and Methods
We analyzed the frequency, causes and treatment of dislocation of polyethylene insertion among various causes of failure of unicompartmental knee arthroplasty. We studied 69 knee joints of 65 patients who underwent medial unicompartmental knee arthroplasty using from June 2005 to December 2010. Average age was 61.8 and average follow-up period was 20 months. Radiologic results evaluated preoperative and postopertative mechanical axis deviation, tibio-fibular angle and postoperative implant position in total 69 knees(A group), failed 15 cases(B group) and 10 cases(C group) of bearing dislocation. We demonstrated treatment on failure group and analyzed preoperative and postoperative HSS and Lysolm score.Purpose
Materials and Methods
Since Smith-Peterson's glass mold arthroplasty in 1939, hip resurfacing arthroplasty was developed and introduced to orthopaedic surgery field but it had many problem like early loosening. Recently it is being popular for some indication as development of new implant design and manufacturing. There are still many suggested advantages of hip resurfacing arthroplasty. These include bone conservation, improved function as a consequence of retention of the femoral head and neck and more precise biomechanical restoration, decreased morbidity at the time of revision arthroplasty, reduced dislocation rates, normal femoral loading and reduced stress-shielding, simpler management of a degenerated hip with a deformity in the proximal femoral metaphysic, an improved outcome in the event of infection, and a reduced prevalence of thromboembolic phenomena as a consequence of not using instruments in the femur. But, there are limited or inconsistent data to support some of these claims regarding the benefits of hip resurfacing including the potential for a more natural feel because of the minimal disturbance of the proximal part of the femur resulting in a better and faster functional outcome. We evaluate the short term results of hip resurfacing arthroplasty using custom patient-specific tooling for prosthesis placement for better standardization. 40 cases, 36 patients(male:20, female:16) those of who were candidates of a Hip Resurfacing procedure, participated in the study. Mean follow up period was 2.5 years (8 months ∼3 years). A CT scan was performed on each patient and a 3D model was generated using the computer tomography dataset. From this model a bone-surface skin was extracted and this data set was used to create a personalized jig. Detailed analysis of the native bone structure was then used to preoperatively plan the appropriate size and position of the implant. A mean 7 degree corrective valgus angle was prescribed on all cases. Postoperative radiological datasets were superimposed onto preoperative plan position and offsets were measured. Operative times were recorded per step during the procedure. Surgeon comfort and ease of use was also noted.Introduction
Materials and Methods
We have performed total knee arthroplasties for valgus and varus in the knees of one person and investigate the clinical characteristics of these patients and the relationship between the kind of deformity and postoperative result. From March 2002 to February 2010, 25 patients who had simultaneous varus and valgus knee deformities underwent total knee arthroplasties and followed more than 12 months were included. The average age was 66.9 years and the average follow-up period was 61.1 months. Follow-up imaging assessments were taken and clinical outcome were evaluated using HSS score at last follow-up.Background
Methods
We hypothesised whether MIS techniques confer any benefit when treating thoracolumbar burst fractures. This was a prospective, non-randomised study over the past seven years comparing conservative (bracing:n=27), conventional surgery (open techniques:n=23) and MIS techniques (n=21) for stabilisation and correction of all thoracolumbar spinal fractures with kyphosis of >200, using Camlok S-RAD 90 system (Stryker Spine). All patients previously had normal spines, sustained only a single level burst fracture (T12, L1 or L2) as their only injury. Age range 18–65 years. All patients in both operatively treated groups were corrected to under 100 of kyphosis, posteriorly only. All pedicle screws/rods were removed between 6 months and 1 year post surgery to remobilise the stabilised segments once the spinal fracture had healed, using the original incisions and muscle splitting/sparing techniques. Patients were assessed via Oswestry Disability Index (ODI) and work/leisure activity status 1 year post fracture. The conservatively treated group fared worst overall, with highest length of stay, poorest return to work/activity, and with a proportion (5/27) requiring later intervention to deal with post-traumatic deformity. 19/27 returned to original occupation, at average 9 months. ODI 32%. Conventional open techniques fared better, with length of stay 5 days, most (19/23) returning to original work/activity, and none requiring later intervention. Average return to work was at 4 months. ODI 14%. MIS group fared best, with shorter length of stay (48 hours), all returning to original work/activity at average 2 months, and none requiring later intervention. ODI negligible. There was no loss of correction in either operatively treated groups. The Camlok S-RAD 90 system is a powerful tool for correction of thoracolumbar burst fractures, and maintains an excellent correction. MIS techniques provide the best outcomes in treating this group of spinal fractures, and offer patients the best chance of restoration to pre-fracture levels of activity.
Haemophilia care has steadily improved over the years and especially so during the last decade. The routine use of prophylactic treatment has undoubtedly resulted in a significant improvement in the life-style, quality of life and life expectancy of these patients. However despite our best efforts there is still a group of young adults who have a severe degree of knee joint destruction as a result of repeated articular bleeding episodes during their early years. The knee is the most common joint affected in haemophilia (50%). The repeated articular bleeding episodes during the patients' early years leads to the onset of pain and significant functional disability at a time when they require the best possible quality of life. The major objective of total joint replacement is to reduce the level of pain in the affected joint and, in addition, a significant reduction in the frequency and number of joint bleeds, which improves both function and mobility. The results of 60 primary total knee replacements performed in 42 patients with severe haemophilia between 1983 and 2003 were reviewed retrospectively. Functional results were assessed using the Hospital for Special Surgery (HSS) knee score both pre- and post-operatively. Kaplan-Meier survivorship analysis was used to calculate prosthetic survival. The mean age of patients was 43.35 (range 25-70yrs). The overall prevalence of infection was less than 2%. The HSS clinical score was excellent or good for 95% of the knees. We believe that total joint replacement is a safe and effective procedure in the management of haemophilic joint arthropathy. The latest techniques using continuous infusion and recombinant factor replacement have gone a long way to reducing the complications rate and to achieving results that match those of the general population.
