Symptomatic cobalt toxicity from a failed total
hip replacement is a rare but devastating complication. It has been reported
following revision of fractured ceramic components, as well as in
patients with failed metal-on-metal articulations. Potential clinical
findings include fatigue, weakness, hypothyroidism, cardiomyopathy,
polycythaemia, visual and hearing impairment, cognitive dysfunction,
and neuropathy. We report a case of an otherwise healthy 46-year-old
patient, who developed progressively worsening symptoms of cobalt
toxicity beginning approximately six months following synovectomy
and revision of a fractured ceramic-on-ceramic total hip replacement
to a metal-on-polyethylene bearing. The whole blood cobalt levels
peaked at 6521 µg/l. The patient died from cobalt-induced cardiomyopathy.
Implant retrieval analysis confirmed a loss of 28.3 g mass of the
cobalt–chromium femoral head as a result of severe abrasive wear
by ceramic particles embedded in the revision polyethylene liner.
Autopsy findings were consistent with heavy metal-induced cardiomyopathy. We recommend using new ceramics at revision to minimise the risk
of wear-related cobalt toxicity following breakage of ceramic components. Cite this article:
Radiostereometric Analysis (RSA) is a well developed imaging technique used to estimate implant fixation of orthopaedic implants in randomized clinical trials. The precision of RSA depends on a number of factors including image quality related to the individual modality properties. This study assesses the precision of RSA with a novel Digital Radiography (DR) system compared to a CR imaging system using different imaging techniques. Additionally, the study assesses the precision of locating beads embedded in a modified spine pedicle screw. A modified titanium spinal pedicle screw 4.5 mm diameter, 35 mm length, marked with two 1.0 mm tantalum beads, one inside the head and one near the screw tip was inserted into a bovine tibia segment. Six additional 1.0 mm tantalum beads were inserted into the bone segment – superiorly, distally and adjacent to the pedicle screw. The phantom was placed on a standard clinical diagnostic imaging bed above a custom RSA carbon fiber calibration cage (Halifax Biomedical Inc.). A pair of DR or CR imaging plates were placed below the calibration cage and irradiated 15 times at 100, 125 kV at 2.5 mAs. To determine precision, the standard deviation of 3D vector distances between beads was determined using RSA for each of the different imaging parameters.Purpose
Method
The purpose of this study was to compare the clinical outcomes and complications following bilateral simultaneous total knee arthroplasty in high body mass index (BMI) patients(>30kg/m2) to those of patients with a BMI<30 kg/m2. Using data from an academic arthroplasty database and review of clinic charts we obtained health related quality of life (SF-12), and disease specific functional outcome scores (WOMAC or Oxford Knee Score). We also assessed length of hospital stay, ASA grade and transfusion requirements. Sixty six patients had a BMI<30 and 151 patients had a BMI>30.Introduction
Materials and Methods
Current practice requires all post-operative hip and knee arthroplasty patients complete a series of clinical questionnaires at each visit. The patients responses to these questionnaires are used as a clinical evaluation tool for the surgeons to assess functionality, satisfaction and pain at routine pre and post-operative visits. The recent installation of 4 touch screen computer terminals, located in the patient waiting area, has created the opportunity to have the patients complete these questionnaires by using only the touch screen entry system. This eliminates the need for clinic staff to manually enter the patients responses into the clinics database, eliminate potential data entry errors, and will significantly reduce the amount of time and paper required to prepare questionnaires for each patient. In addition to possibly increasing the volume of data we can collect in our clinic, this also allows the surgeon to have immediate access to the patients responses which can be reviewed prior to seeing the patient in the office. Our goal was to determine the overall level of patient satisfaction with using the new touch screen direct entry system, the efficiency of completion and the quality of data entry occurring from the direct entry system. During the month of April, 2010, a consecutive series of 100 patients entering the orthopaedic clinic, were directed to the touch screen kiosks to complete the required questionnaires (SF-12, Oxford Knee/Hip, Harris Hip/Knee Society Score, and the Patient Satisfaction Survey). Once the patients completed the touch screen questionnaires they were asked to complete a paper copy of the Touch Screen Satisfaction Questionnaire. This questionnaire asked 6 questions regarding their satisfaction with the touch-screen system, the ease/difficulty of use, and which method they would prefer to complete such questionnaires if given a choice.Purpose
Method
Radiostereometric Analysis (RSA) is an imaging method that is increasingly being utilized for monitoring fixation of orthopaedic implants in randomized clinical trials. Extensive RSA research has been conducted over the last 35+ years using standard clinical x-ray acquisition modalities that irradiate screen/film media or Computed Radiography (CR) plates. The precision of RSA can depend on a number of factors including modality image quality. This study assesses the precision of RSA with a novel Digital Radiography (DR) system compared to a CR imaging system using different imaging techniques. Additionally, the study assesses the precision of locating beads embedded in a modified spine pedicle screw.Introduction
Objective
Despite being matched by age, gender and modified Charnley classification, there were significant differences in post-operative functional scores. The revision TKR group’s mean WOMAC score was 73 (SD 17), compared to the primary group’s mean score of 84 (SD 14), p=0.002. Similarly, the revision group’s mean SF-12 PCS score was 35 (SD 8) compared to the primary group’s superior score of 44 (SD 10), p<
0.0001. There was no differences detected in post-operative SF-12 mental component scores; 49 (SD 12) for the revision group compared to 53 (SD 10) for the primary group, p=0.11.
The purpose of the present study was to investigate the role of E2 on the responsiveness of the AIS cells to the melatonin, to determine the expression of estrogens receptors (ERα and ERβ) in AIS tissues and to clarify the impact of estrogen receptor gene polymorphisms in the pathogenesis of AIS.
Supported by the Fondation Yves Cotrel, Institut de France
The twelve matte and twelve polished surfaces of hemi-arthroplasties were contaminated with Tremendous suffering is associated with infection following total joint arthroplasty. To reduce infection risk, some surgeons use pulse irrigation prior to wound closure. This practice is based on the assumption that pulse irrigation will more effectively remove adherent bacteria. However, there has been no study of the effectiveness of pulse irrigation in clearing bacteria from prosthetic surfaces. The hypothesis of this study is that pulse irrigation is more effective than bulb irrigation in removing intra-operative bacterial contaminants from prosthetic surfaces. The matte and polished surfaces of hemiarthroplasties were studied separately. Each surface was contaminated with Twelve matte and twelve polished surfaces were examined using both irrigation types with corresponding non-irrigation reference values. Results are expressed as the percentage of contaminant bacteria recovered. The matte finish groups showed median values of 1.46 and 2.88x10−2 while the polished finish groups showed 1.49x10−3 and 2.83x10−6 with bulb and pulse irrigation, respectively. The difference between irrigation types is significant ( Pulse irrigation was more effective than bulb irrigation in removing contaminant bacteria from the prosthetic surfaces studied.
Allogenic blood transfusions are frequent sequellae of hip and knee arthroplasty with potentially deleterious consequences. A prospective collection of a comprehensive data set of 1,185 knee and 1,064 hip arthroplasty patients including primary and revision surgeries was completed with analysis of allogenic and predonated blood usage, blood salvage systems and costs. The most effective strategy in reducing allogenic blood transfusion is the use of a blood salvage system. The most expensive strategy is the use of blood salvage systems with predonation. The least expensive and least effective strategy is no predonation of blood and no blood salvaging system. The purpose of this study is to evaluate the usage, effectiveness and cost of blood salvage technologies in total hip and knee arthroplasty. The most effective strategy in reducing allogenic blood transfusion is the use of a blood salvage system. The most expensive strategy is the use of blood salvage systems with predonation. The least expensive and least effective strategy is no predonation of blood and no blood salvaging system. More than half of the predo-nated blood collected was never used. Blood loss in total hip and knee arthroplasty can have significant deleterious physiologic effects on patients. There are potential health risks with allogenic blood transfusion as well as patient anxiety toward allogenic transfusion. Recent advances in blood management provide additional options that need further evaluation. The lowest cost strategy was no predonation and no blood salvage system at an average of $30 per patient, but with a 14% incidence of allogenic transfusion. Pre-donation alone had a cost of $330 with a 12% transfusion rate. Predonated blood was wasted in 60% of knee arthroplasties and 48% of hip arthroplasties. The Consta Vac and OrthoPAT blood salvage systems had a cost of $110 and $365 with 5% and 7% transfusion rate, respectively. A prospective collection of a two-year comprehensive data set of 1,185 knee and 1,064 hip arthroplasty patients including both primary and revision surgeries was completed. Analysis of blood counts, allogenic and predonated blood usage, blood salvage systems, length of stay, demographics and costs were performed.
Surgical treatment of recurrent dislocation after total hip arthroplasty (THA) is challenging with often disappointing results. The influence of the posterior hip capsule is important, and restoration of its function is a major goal of treatment. We describe our experience using an Achilles tendon allograft as a checkrein to limit hip internal rotation and to prevent posterior instability. Twenty unstable THAs were treated using this technique, eliminating instability in fifteen. At an average follow-up of 3.6 years, Achilles tendon allograft augmentation has proven a useful adjunct for the treatment of recurrent posterior dislocation after THA in selected patients. The purpose of this study is to review our results with a novel treatment for recurrent dislocation after total hip arthroplasty (THA) using an Achilles tendon allograft as a checkrein to prevent instability. Achilles tendon allograft augmentation has proved to be a useful adjunct for the treatment of recurrent posterior dislocation after THA in selected patients. Surgical treatment of recurrent dislocation after total hip arthroplasty (THA) is challenging with often disappointing results. Among possible causes of dislocation, the influence of the static soft tissue restraint provided by the hip capsule is important, and restoration of its integrity and function is a major goal of treatment. We describe a new technique in which an Achilles tendon allograft is employed as a checkrein to limit hip internal rotation and to prevent posterior instability. Twenty unstable THAs with recurrent instability were treated using this technique, eliminating instability in fifteen at an average follow-up of 3.6 (0.5 to 6.6) years. Prospective data was collected and reviewed on the first twenty patients with recurrent THA instability stabilized with an Achilles tendon allograft. Head and liner exchanges accompanied the allograft. Use of a constrained cup was considered a failure. Instability was successfully controlled in 75% of patients with use of the Achilles allograft. The technique is an important addition to the treatment arsenal of this difficult problem.
Allogenic blood transfusions are frequent sequellae of hip and knee arthroplasty with potentially deleterious consequences. A prospective collection of a comprehensive data set of 1,185 knee and 1,064 hip arthroplasty patients including primary and revision surgeries was completed with analysis of allogenic and predonated blood usage, blood salvage systems and costs. The most effective strategy in reducing allogenic blood transfusion is the use of a blood salvage system. The most expensive strategy is the use of blood salvage systems with predonation. The least expensive and least effective strategy is no predonation of blood and no blood salvaging system. The purpose of this study is to evaluate the usage, effectiveness and cost of blood salvage technologies in total hip and knee arthroplasty. The most effective strategy in reducing allogenic blood transfusion is the use of a blood salvage system. The most expensive strategy is the use of blood salvage systems with predonation. The least expensive and least effective strategy is no predonation of blood and no blood salvaging system. More than half of the predonated blood collected was never used. Blood loss in total hip and knee arthroplasty can have significant deleterious physiologic effects on patients. There are potential health risks with allogenic blood transfusion as well as patient anxiety toward allogenic transfusion. Recent advances in blood management provide additional options that need further evaluation. The lowest cost strategy was no predonation and no blood salvage system at an average of $30 per patient, but with a 14% incidence of allogenic transfusion. Pre-donation alone had a cost of $330 with a 12% transfusion rate. Predonated blood was wasted in 60% of knee arthroplasties and 48% of hip arthroplasties. The Consta Vac and OrthoPAT blood salvage systems had a cost of $110 and $365 with 5% and 7% transfusion rate, respectively. A prospective collection of a two-year comprehensive data set of 1,185 knee and 1,064 hip arthroplasty patients including both primary and revision surgeries was completed. Analysis of blood counts, allogenic and predonated blood usage, blood salvage systems, length of stay, demographics and costs were performed.