Advanced Age,Obesity and Continuous Femoral Nerve Blockade are Independent Risk Factors for Inpatient Falls After Primary Total Knee Arthroplasty

We asked whether femoral nerve blockade (FNB) was an independent risk factor for inpatient post-operative falls after total knee arthroplasty (TKA). Data on 2197 primary TKAs were collected from our institution between 2003 and 2010. Patient demographics, type and duration of blocks were considered predictors of falls in a logistic regression model. Among 60 (2.7%) falls, the odds ratio was 1.04 (1.0–1.07; p = 0.008) for each 1 year of increased age above the mean (66 years), 2.4 (1.3–4.5; p = 0.005) for BMI > 30 kg/m² and 4.4 (1.04–18.2; p = 0.04) for continuous FNB. Single-shot FNB did not increase risk. No fall resulted in operative morbidity. The use of continuous FNB should be cautioned, especially in patients with other risk factors such as obesity and advanced age.     

Primary Musculoskeletal Mycobacterium Infection With Large Cystic Masses After Total Hip Arthroplasty

Primary mycobacterial infections in the musculoskeletal system are rare with a limited number of published case reports. This report describes a case involving a primary musculoskeletal tuberculous abscess. A 62-year-old male patient who had a right total hip arthroplasty performed 8 years earlier, using metal-on-metal articulation presented with a 1-year history of non-tender masses on his right thigh. Initially, it was assumed he had metallosis. Intraoperatively, an incision into the mass was conducted which resulted in draining of a whitish-grey pus like fluid. A diagnosis of tuberculosis was confirmed with both microscopic and histological examination. The patient was treated over a course of six months with an anti-tuberculosis medication regimen following the confirmation of a solitary soft tissue tuberculosis infection. At the 24 month follow-up, the patient was asymptomatic with no relapse of the mass.     

Surgical Treatment of Trochanteric and Cervical Hip Fractures in the United States: 2000–2009

The objective of this study was to evaluate the most common treatments performed for hip fractures over the last decade in the United States. The leading treatment for trochanteric fractures was internal fixation, accounting for 96%–98% of surgical treatments each year. For cervical fractures, hemiarthroplasty (HA), total hip arthroplasty (THA), and internal fixation were performed nearly 61%, 5%, and 33% of the time, respectively, each year without any sign of change during the period assessed. The surgical choice for cervical fractures varied greatly by patient age. In 2009, two-thirds of patients younger than 60 years underwent internal fixation while two-thirds of patients 60 years or older underwent HA. Regardless of patient age, HA was performed more often than THA for cervical hip fractures.     

Retrospective Evaluation of the Duracon Periapatite-Coated Tibial Tray : Midterm Results and Factors Affecting Success

This study reports the retrospective radiographic outcome of a series of 63 consecutive total knee arthroplasties using an uncemented hydroxyapatite-coated Duracon cruciate-retaining tibial baseplate (Stryker Howmedica Osteonics Corp, Mahwah, NJ). Sixty-three knees were assessed at a mean follow-up of 65 months. The knees were primarily diagnosed with osteoarthritis with a mean age of 61 years. Radiographic analysis showed 6 knees with tibial baseplate radiolucencies, with all of these resolving or improving over the course of the study. All tibial baseplates were implanted with the concomitant use of autologous bone slurry. There were no reoperations for aseptic loosening, fracture, or patellofemoral problems. This intermediate study demonstrates excellent radiographic outcomes for uncemented hydroxyapatite-coated Duracon cruciate-retaining tibial baseplates and evaluates other factors felt to be important in the success of a cementless implant.     

Results of Primary Total Knee Arthroplasty in Jehovah's Witness Patients

Total knee arthroplasty can be challenging in Jehovah's Witnesses, as these patients do not accept blood transfusions. We reported our experiences with a special blood management protocol for these patients who underwent total knee arthroplasty. There were 124 self-reported Jehovah's Witnesses who had a mean age of 64 years and who underwent total knee arthroplasties between 1998 and 2009. Mean follow-up was 60 months (range, 24-120 months). Implant survivorship, with revision for aseptic component failure as an end point, was 98%. At the final follow-up, mean Knee Society objective and function score improved to 91and 81 points, respectively. The authors believe that this blood management protocol was responsible for performing safe and transfusion-free total knee arthroplasties that can ultimately lead to excellent outcomes.     

Operative Treatment of Early Peri-Prosthetic Femur Fractures Following Primary Total Hip Arthroplasty

The risk factors for and results of operatively treated peri-prosthetic femoral fractures sustained within 90 days following primary THA were evaluated. 5,313 consecutive THAs were reviewed and 32 (0.60%) fractures were identified which included 9 A_g, 2 B₁, 18 B₂, 1 B₃, and 2 A_g/B₂ fractures. 19 (61%) patients sustained 23 complications including 9 greater trochanter non-unions, 2 femoral shaft non-unions, 3 patients with Brooker III HO, and 2 deep infections. 7 patients (23%) required a second operative procedure and one patient required a third. Peri-prosthetic fractures were associated with advancing age, female gender, developmental hip dysplasia, and cementless metaphyseal engaging components, particularly flat wedge tapers. Overall, operative treatment of acute peri-prosthetic fractures is associated with a high rate of complications (61%) and re-operation (23%).     

Two-Stage Arthroplasty for Prosthetic Joint Infection : A Systematic Review of Acute Kidney Injury,Systemic Toxicity and Infection Control

Periprosthetic infections of hip and knee joints are now treated by two-stage revision arthroplasty with an infection control rate of 91%. The present systematic review studied the reported incidence of acute kidney injury (AKI) and infection recurrence from January 1989 to June 2012 to assess the risk–benefit ratio of antibiotic spacer use. Ten observational studies (n = 544 patients) with clinical outcomes showed an average incidence of AKI of 4.8%. The average reported persistence or recurrence rate of infection was 11% during a follow-up period that ranged from 13 to 108 months. The risk–benefit ratio presently favors treatment although there appears to be higher complication rates and incidence of AKI than previously reported. Marked heterogeneity in practice and lack of detail in reporting precluded more robust quantitative synthesis. Clinicians need to be aware of the potential risk of AKI, particularly in high-risk patients; practice patterns for the use of antibiotic spacers need to be standardized.     

Radiographically Measured Total Knee Wear is Constant and Predicts Failure

Knee wear is commonly measured with the most recent radiograph based on the assumption that wear progresses at a constant rate. Changing patient activity or in vivo polyethylene deterioration are examples of factors that could cause wear rates to change over time. Using six or more radiographs on each of 251 knees over a mean 10-year follow-up, we determined the pattern of polyethylene wear. 92% of knees had linear wear with a mean wear rate of 0.09 ± 0.12 mm/yr. Ten knees (4%) had late accelerated wear. Knees with accelerated wear and those with a wear rate of 0.15 mm/yr or greater had lower survivorship rates. We conclude that wear is linear with rare exceptions and that higher wear is correlated with failure.     

Efficacy of Multimodal Perioperative Analgesia Protocol With Periarticular Medication Injection in Total Knee Arthroplasty : A Randomized,Double-Blinded Study

Pain control is necessary for successful rehabilitation and outcome after total knee arthroplasty. Our goal was to compare the clinical efficacy of periarticular injections consisting of a long-acting local anesthetic (ropivacaine) and epinephrine with and without combinations of an α2-adrenergic agonist (clonidine) and/or a nonsteroidal anti-inflammatory agent (ketorolac). In a double-blinded controlled study, we randomized 160 patients undergoing total knee arthroplasty to receive 1 of 4 intraoperative periarticular injections: Group A, ropivacaine, epinephrine, ketorolac, and clonidine; Group B, ropivacaine, epinephrine, and ketorolac; Group C, ropivacaine, epinephrine, and clonidine; Group D (control), ropivacaine and epinephrine. Compared with Group D, Group A and B patients had significantly lower postoperative visual analog pain scores and nurse pain assessment and Group C patients had a significantly greater reduction in physical therapist pain assessment. We found no differences in other parameters analyzed.     

Incidence of Osteolysis in Total Knee Arthroplasty : Comparison Between Radiographic and Retrieval Analysis

Detection of polyethylene wear and osteolysis in total knee arthroplasty using radiographs is imprecise. To correlate radiographic findings with retrieved tibial component analysis, we reviewed knee revision cases. A joint registry was used to identify all knee revisions. Radiographic scoring systems were developed. Radiographs were analyzed for osteolysis and implant alignment. Polyethylene liner retrievals were visually and optically graded for surface damage. Statistical analyses that included correlation analysis and Mann-Whitney U test were used. When osteolysis was found, radiographic scores and delamination score were significantly higher (P = .047 and P = .014, respectively). Delamination is a good indicator for polyethylene wear and osteolysis. There is a need to develop in vivo methods to identify polyethylene changes and thereby prevent severe clinical outcomes.