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Background: Infection is common following high-energy open tibial fractures. Understanding the wound bioburden may be critical to infection risk reduction strategies. This study was designed to identify the bioburden profile of high-energy open tibial fractures at the time of definitive wound closure or coverage and determine the relationship to subsequent deep infection. Methods: This multicenter prospective study enrolled 646 patients with high-energy open tibial fractures requiring a second debridement surgery and delayed wound closure or coverage. Wound samples were obtained at the time of definitive closure or coverage and were cultured in a central laboratory. Cultures were also subsequently obtained from patients who underwent a fracture-site reoperation. Results: Two hundred and six (32%) of the wounds had a positive culture at the time of closure or coverage. A single genus was identified in 154 (75%) of these positive cultures and multiple genera, in 52 (25%). Gram-positive cocci (GPCs) were identified in 98 (47%) of the positive cultures. Staphylococci were identified in 64 (31%) of the cultures, and 53 (83%) of these were coagulase-negative (CONS). Enterococci were identified in 26 (13%) of the cultures. Gram-negative rods (GNRs) were identified in 100 (49%) of the cultures; the most frequent GNR genera identified were Enterobacter (39, 19%) and Pseudomonas (21, 10%). Positive cultures were subsequently obtained from 154 (50%) of 310 revision surgeries. A single genus was identified in 85 (55%) of the 154 and multiple genera, in 69. GPCs were identified in 134 (87%) of the 154 positive cultures, staphylococci were identified in 94 (61%), and GNRs were identified in 100 (65%). Conclusions: The bioburden in high-energy open tibial fractures at delayed closure or coverage was often characterized by pathogens of multiple genera and of genera that are nonresponsive to typically employed antibiotic prophylaxis. Awareness of the final wound bioburden might inform strategies to lower the infection rate. Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Despite its well-established limitations, culture remains the gold standard for microbial identification in periprosthetic joint infection (PJI). However, there are no benchmarks for the time to positivity (TTP) on culture for specific microorganisms. This study aimed to determine the TTP for pathogens commonly encountered in PJI. Methods: This retrospective, multicenter study reviewed prospectively maintained institutional PJI databases to identify patients who underwent hip or knee revision arthroplasty from 2017 to 2021 at 2 tertiary centers in the United States and Germany. Only patients who met the 2018 International Consensus Meeting (ICM) criteria for PJI and had a positive intraoperative culture were included. TTP on culture media was recorded for each sample taken intraoperatively. The median TTP was compared among different microbial species and different specimen types. Data are presented either as the mean and the standard deviation or as the median and the interquartile range (IQR). Results: A total of 536 ICM-positive patients with positive cultures were included. The mean number of positive cultures per patient was 3.9 ± 2.6. The median TTP, in days, for all positive cultures was 3.3 (IQR, 1.9 to 5.4). Overall, gram-negative organisms (TTP, 1.99 [1.1 to 4.1]; n = 225) grew significantly faster on culture compared with gram-positive organisms (TTP, 3.33 [1.9 to 5.8]; n = 1,774). Methicillin-resistant Staphylococcus aureus (TTP, 1.42 [1.0 to 2.8]; n = 85) had the fastest TTP, followed by gram-negative rods (TTP, 1.92 [1.0 to 3.9]; n = 163), methicillin-sensitive Staphylococcus aureus (TTP, 1.95 [1.1 to 3.3] n = 393), Streptococcus species (TTP, 2.92 [1.2 to 4.3]; n = 230), Staphylococcus epidermidis (TTP, 4.20 [2.4 to 5.5]; n = 555), Candida species (TTP, 5.30 [3.1 to 10]; n = 63), and Cutibacterium acnes (TTP, 6.97 [5.9 to 8.2]; n = 197). When evaluating the median TTP according to specimen type, synovial fluid (TTP, 1.97 [1.1 to 3.1]; n = 112) exhibited the shortest TTP, followed by soft tissue (TTP, 3.17 [1.4 to 5.3]; n = 1,199) and bone (TTP, 4.16 [2.3 to 5.9]; n = 782). Conclusions: To our knowledge, this is the first study to examine the TTP of common microorganisms that are known to cause PJI. Increased awareness of these data may help to guide the selection of appropriate antimicrobial therapy and to predict treatment outcomes in the future. Nonetheless, additional studies with larger cohorts are needed to validate these benchmarks. Level of Evidence: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Periprosthetic infections after pelvic reconstruction are common, with reported rates ranging from 11% to 53%. Management of these infections is troublesome, as they commonly necessitate multiple surgical interventions and implant removal. The epidemiology and outcomes of these infections are largely unknown. The aim of this study was to analyze the causative microorganisms and the clinical outcome of treatment in a series of patients with pelvic endoprostheses affected by infection following tumor resection.Methods: In this retrospective, multicenter cohort study, we identified all patients who developed an infection after endoprosthetic reconstruction in periacetabular tumor resection, between 2003 and 2017. The microorganisms that were isolated during the first debridement were recorded, as were the number of reoperations for ongoing infection, the antimicrobial treatment strategy, and the outcome of treatment.Results: In a series of 70 patients who underwent pelvic endoprosthetic reconstruction, 18 (26%) developed an infection. The type of pelvic resection according to the Enneking-Dunham classification was type P2-3 in 14 (78%) of these patients and type P2 in 4 (22%). Median follow-up was 66 months. Fourteen (78%) of the 18 patients with infection had a polymicrobial infection. Enterobacteriaceae were identified on culture for 12 (67%). Of a total 42 times that a microorganism was isolated, the identified pathogen was gram-negative in 26 instances (62%). Microorganisms associated with intestinal flora were identified 32 times (76%). At the time of latest follow-up, 9 (50%) of the patients had the original implant in situ. Of these, 2 had a fistula and another 2 were receiving suppressive antibiotic therapy. In the remaining 9 (50%) of the patients, the original implant had been removed. At the time of final follow-up, 3 of these had a second implant in situ. The remaining 6 patients had undergone no secondary reconstruction.Conclusions: Infections that affect pelvic endoprostheses are predominantly polymicrobial and caused by gram-negative microorganisms, and may be associated with intestinal flora. This differs fundamentally from mono-bacterial gram-positive causes of conventional periprosthetic joint infections and may indicate a different pathogenesis. Our results suggest that prophylaxis and empiric treatment may need to be re-evaluated.Level Of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

A review of the article "Acetabular and Femoral Measurements and Relation to Hip Pathologies" by K. Linnea Welton et al. is presented.

Background: Pelvic discontinuity is uncommon and presents the surgeon with complex reconstructive challenges. The objective of this study is to report the results of current strategies used in the treatment of pelvic discontinuity.Methods: We retrospectively analyzed prospectively collected data on 113 consecutive revision total hip arthroplasties performed for the treatment of unilateral pelvic discontinuity at a single institution. The study included 18 male and 95 female patients with a mean age of 63 years at the time of revision surgery. Preoperative, immediate postoperative, and latest follow-up radiographs were reviewed to assess healing of the discontinuity as well as acetabular component stability. Treatment modalities included an uncemented cup with a posterior column plate (50 hips; 44%), a cup-cage construct (27 hips; 24%), an antiprotrusio cage with or without a posterior column plate (26 hips; 23%), and an uncemented cup alone (10 hips; 9%). The average duration of follow-up for each of these types of surgical reconstruction was similar (range, 3.9 to 7.2 years).Results: Five-year revision-free survivorship of the implant was best with a cup-cage construct (100%) and worst with an uncemented cup with a posterior column plate (80%) and a cup alone (80%). Healing of the discontinuity was achieved in 50% of the hips with an uncemented cup alone, 74% of the hips with an uncemented cup and a posterior column plate, 74% of the hips with a cup-cage construct, and 88% of the hips with an antiprotrusio cage construct (91% of these hips when structural allograft was used). The overall complication rate was 26.5%. The average Harris hip score improved from 54 preoperatively to 69 postoperatively (95% confidence interval: 50 to 57 preoperatively and 65 to 72 postoperatively; p = 0.017).Conclusions: Improved survivorship and healing rates were seen in this series when a reconstruction cage was used as an adjunct to an uncemented cup (cup-cage) or in combination with structural allograft bone that bridged the discontinuity.Level Of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Sarcopenia is a condition of clinically relevant loss of muscle mass and function. Acetabular fractures in elderly patients are common and difficult to treat. This study aimed to determine if sarcopenia is common in elderly patients with acetabular fractures and correlates with lower-energy mechanisms of injury, higher rates of complications, and higher mortality than patients with normal muscle mass.Methods: The Rhode Island Hospital Trauma Database was queried for patients who were ≥60 years of age from 2005 to 2014 using the International Classification of Diseases, Ninth Revision, code for closed acetabular fracture, 808.0. Charts were retrospectively reviewed for demographic data, operative intervention, mechanism of injury, mortality, comorbidities, and other factors. Computed tomography (CT) was used to determine the muscle cross-sectional area and to calculate the skeletal muscle index.Results: The database revealed 192 patients coded for acetabular fracture; of these, 181 were correctly diagnosed. Ninety-nine patients had recorded body mass index (BMI) and adequate CT scans to measure the skeletal muscle index. Forty-two patients (42.4%) had sarcopenia, and 57 patients (57.6%) did not have sarcopenia. There were no significant differences in demographic characteristics between the groups with the exception of BMI and sex. BMI was higher in patients who did not have sarcopenia (31.7 kg/m) than it was in patients with sarcopenia (23.6 kg/m) (p < 0.001). Male sex was significantly greater (p = 0.0104) in patients with sarcopenia at 76.2% (32 of 42 patients) than in patients without sarcopenia at 50.9% (29 of 57 patients). Fractures in patients without sarcopenia were associated with a higher-energy mechanism of injury in 78.9% of cases compared with 52.4% of cases of patients with sarcopenia (p = 0.005). Sarcopenia was significantly associated (p = 0.0419) with increased 1-year mortality (28.6%) compared with the absence of sarcopenia (12.3%). This association was even stronger if in-hospital mortality was excluded (p = 0.00074). Finally, anterior column fractures were more likely (p = 0.017) to be sustained by patients with sarcopenia at 47.6% (20 patients) than by patients who did not have sarcopenia at 24.6% (14 patients).Conclusions: Sarcopenia is common in elderly patients with acetabular fractures and is associated with lower-energy mechanisms, anterior column fractures, and higher risk of 1-year mortality.Level Of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Wide variability in cup orientation has been reported. The aims of this study were to determine how accurate surgeons are at orientating the acetabular component and whether factors such as visual cues and the side of operating table improved accuracy.Methods: A pelvic model was positioned in neutral alignment on an operating table and was prepared as in a posterior approach. Twenty-one surgeons (9 trainers and 12 trainees) were tasked with positioning an acetabular component in a series of target orientations. The orientation of the component was measured using stereophotogrammetry, and the difference between the achieved orientation and the target orientation was calculated. Tasks included stating the surgeon's preferred orientation and thereafter placing the cup in that orientation, reproducing visual cues (transverse acetabular ligament and alignment guide), altering orientation by 10°, and estimating orientation while on the assistant's side.Results: The preferred inclination was 42° and the preferred anteversion was 21°. On average, surgeons decreased the inclination by 4° and increased the anteversion by 11° when tasked with replicating their desired orientation. The variability (defined as 2 standard deviations) in achieving a target orientation was 14°. The use of visual cues, such as the transverse acetabular ligament or the alignment guide, significantly improved accuracy to 1° for anteversion (p < 0.001) and -3° for inclination (p = 0.003). In addition, the use of an alignment guide reduced the variability by one-third. Trainees and trainers had similar accuracy and variability. There was greater variability in assessing cup inclination when standing on the assistant's side compared with the surgeon's side of the table, which has implications for training.Conclusions: Surgeons overestimate operative inclination and underestimate anteversion, which is of benefit, as this, on average, helps to achieve the desired radiographic cup orientation. Although the use of visual cues helps, conventional techniques result in a large variability in acetabular component orientation. New and better guides and methods for training need to be developed. [ABSTRACT FROM AUTHOR]

Background: The purposes of this study were to evaluate acetabular remodeling after closed reduction of developmental dysplasia of the hip (DDH) and to delineate the role of osteotomy.Methods: Eighty-four hips with DDH treated with closed reduction and followed until the patient was 8 years of age or older were included in this study. The mean age at closed reduction was 14.0 months (range, 3 to 30 months) and that at the latest follow-up visit was 12.7 years (range, 8.0 to 24.7 years). Osteotomy was performed in 26 hips (31%) during the follow-up period, at an average age of 2.8 years (range, 2.0 to 5.8 years). The acetabular index (AI) and center-edge angle (CEA) were measured, and osteonecrosis was graded. The treatment outcome was evaluated as satisfactory (Severin grade I or II) or unsatisfactory (III or IV). We retrospectively analyzed the associations among radiographic parameters, performance of osteotomy, grade of osteonecrosis, and final outcome.Results: A satisfactory outcome was observed in 67 (80%) of the 84 hips. An osteotomy was not performed in 30 of 34 hips with an AI of <32° and a CEA of >14° at the age of 3 years, and 28 (93%) of these 30 hips showed a satisfactory outcome. Of the 33 hips with an AI of ≥32° and a CEA of ≤14° at the age of 3 years, the 20 that had undergone an osteotomy showed a higher proportion of satisfactory outcomes than the 13 hips that had not (p = 0.01). Three of the 4 hips that showed an unsatisfactory outcome following an osteotomy had an AI of ≥34° at 1 year post-osteotomy. Grade-II, III, or IV osteonecrosis, according to the Bucholz-Ogden classification, developed in 10 of the 84 hips, and these 10 hips had a higher proportion of unsatisfactory outcomes than did those that developed no or grade-I osteonecrosis (p = 0.004).Conclusions: Hips with DDH showing poor acetabular remodeling after closed reduction may benefit from osteotomy. The AI and CEA at the age of 3 years can serve as one of the guidelines for osteotomy. Continued surveillance for acetabular remodeling is required even after osteotomy.Level Of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Aseptic loosening and osteolysis commonly limit the survivorship of total hip prostheses. Retention of a well-fixed acetabular component, rather than full acetabular revision, has multiple advantages, but questions have lingered regarding the clinical success and prosthetic survivorship following this procedure. We examined the impact of acetabular component position, polyethylene type, liner insertion technique, femoral head size, and simultaneous revision of the entire femoral component (as opposed to head and liner exchange) or bone-grafting on mid-term to long-term prosthetic survival following such limited revisions.Methods: One hundred hips in 100 patients with osteolysis, polyethylene wear, or femoral component loosening underwent revision total hip arthroplasty with retention of the acetabular component. Acetabular component inclination and anteversion were measured on prerevision radiographs and were categorized according to predetermined positional safe zones (inclination of 35° to 55° and anteversion of 5° to 25°). Operative reports were reviewed for femoral head size, polyethylene liner type (conventional or highly cross-linked), liner insertion technique (use of the existing locking mechanism or cementation), whether the patient had revision of the entire femoral component, and use of bone graft. Outcomes of interest included the Harris hip score, University of California at Los Angeles (UCLA) activity score, episodes of instability, and need for repeat revision.Results: At an average of 6.6 years (range, two to fourteen years) postoperatively, the Harris hip and UCLA activity scores were both significantly improved compared with the preoperative scores (p < 0.0001 and p < 0.01, respectively). Overall, the failure rate was 13%. In addition, 6% of the patients had postoperative instability. Hips in which the acetabular component was outside of the safe zone for inclination had a higher rate of failure (p = 0.048). Use of conventional, rather than highly cross-linked, polyethylene at the time of revision was also associated with an increased rate of repeat revision (p = 0.025).Conclusions: Revision total hip arthroplasty with retention of the acetabular component is associated with good outcomes in hips with an appropriately positioned, well-fixed acetabular component. Acetabular components outside the safe zone for inclination were at a higher risk for failure, as was use of conventional polyethylene.Level Of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Subtle variations in acetabular morphology have been implicated in several pathologic hip conditions. Although it is understood that the acetabulum forms at the junction of the ilium, ischium, and pubis at the triradiate cartilage, the ossification and development pattern of the posterior wall of the acetabulum is unknown. Standard radiographs and computed tomographic scans used in evaluation of the adolescent hip do not allow a complete assessment of the non-ossified portions of the developing acetabulum. The purpose of this study was to define the currently unknown ossification pattern and development of the posterior wall of the acetabulum and to determine when conventional imaging, with use of computed tomography and radiographs, is appropriate. Methods: One hundred and eighty magnetic resonance imaging examinations in patients who were four to fifteen years old were evaluated by a musculoskeletal radiologist for ossification patterns of the posterior wall of the acetabulum and triradiate cartilage. Correlations were made with available radiographs. Results: Posterior acetabular wall ossification lags behind anterior wall ossification throughout development. On average, the posterior wall of the acetabulum began to ossify at the chronological age of eight years, followed by a discrete rim of posterior calcification (posterior rim sign) at the patient age of twelve years, just prior to the fusion of the posterior acetabular wall elements to the pelvis. This preceded the closure of the triradiate cartilage in all subjects. On average,male patients had fusion of the posterior wall of the acetabulum one to 1.5 years after female patients. Conclusions: The ossification of the posterior wall of the acetabulumis completed in a predictable manner prior to closure of the triradiate cartilage. Clinical Relevance: Prior to closure of the triradiate cartilage (typically at the age of twelve years in girls and fourteen years in boys), magnetic resonance imaging, rather than radiographs and computed tomography, should be used to evaluate a child with hip pain or to measure and characterize acetabular morphology when cross-sectional imaging is indicated. This study characterizes a secondary ossification center along the edge of the posterior wall of the acetabulum that becomes ossified just prior to fusion. This secondary rimossification center should not be confused with pathologic conditions such as labral avulsion or posterior acetabular wall injury. [ABSTRACT FROM AUTHOR]

Background: Arthroscopic surgery of the hip is being increasingly used to diagnose and treat various abnormalities, including acetabular labral tears. Magnetic resonance arthrography has been suggested as the imaging test of choice for the evaluation of the acetabular labrum. There is substantial variability in the previously reported accuracy of magnetic resonance arthrography for diagnosing labral lesions. Interobserver reliability has not been established previously. The purpose of this study was to establish the interobserver reliability and the validity of magnetic resonance arthrography for detecting lesions of the acetabular labrum in a retrospective case series Methods: Two radiologists independently assessed the acetabular labrum on magnetic resonance arthrograms of ninety-five hips in ninety-three patients who underwent hip arthroscopy for a suspected acetabular labral lesion. Magnetic resonance arthrography findings were compared with the gold standard, which was defined as the assessment of the labrum during the hip arthroscopy Results: At arthroscopy, ninety-one labral lesions were identified in the ninety-five hips. The interobserver reliability of detecting labral lesions with magnetic resonance arthrography was fair (kappa = 0.268). Magnetic resonance arthrog-raphy, as interpreted by observers A and B, showed a sensitivity of 86% and 86%, specificity of 75% and 50%, negative predictive value of 19% and 13%, and positive predictive value of 99% and 98%, respectively. Conclusions: Because of its limited reliability and the high prevalence of labral lesions, magnetic resonance arthrog-raphy provides a limited complementary benefit in the detection of labral lesions in patients with a high clinical suspicion of labral pathology. When there is a high clinical suspicion of a labral lesion, magnetic resonance arthrography has a poor negative predictive value and cannot be used to rule out a labral lesion. Physicians should critically consider whether the findings on a magnetic resonance arthrogram will alter the treatment strategy for an individual patient with a clinical suspicion of labral pathology. [ABSTRACT FROM AUTHOR]

Background: Improved metal-on-metal articulations were reintroduced in total hip replacement to avoid the osteolysis sometimes seen with conventional ultra-high molecular weight polyethylene bearings. Osteolysis and local lymphocytic infiltration have been reported at revision of some metal-on-metal devices. We report similar and additional results in a study of second-generation metal-on-metal hip implants retrieved post mortem. Methods: Components and surrounding tissues were collected post mortem from seven patients with nine total hip replacements (Zweymüller SL stem with an Alloclassic cup) with Metasul metal-on-metal articulations. All available patient information was recorded. Radiographs of the hips were evaluated for osteolysis. Sections of joint capsule as well as of the femoral implant with surrounding bone were reviewed, and energy-dispersive x-ray analysis was used to evaluate the composition of wear products. The amount of wear was measured for each component (nine femoral heads and eight cup inserts), when possible, by a coordinate measurement machine with use of the dimensional method. Results: The patients died between three and ten years after arthroplasty, and six of the seven were asymptomatic at the time of death. One patient, with the highest rate of total wear (i.e., wear of femoral head and acetabular cup; 7.6 μm/yr), had increasing hip pain for one year, and histological analysis confirmed the radiographic findings of osteolysis. For two other patients, histological analysis confirmed the radiographic findings of asymptomatic osteolysis. For three patients, histological analysis revealed osteolysis that had escaped conventional radiographic analysis. Joint capsule tissue showed evidence of metallosis in all hips and local lymphocytic infiltration in eight hips. Energy-dispersive x-ray analysis revealed elements attributable to CoCrMo alloy in all hips and traces of corrosion products in three hips. Conclusions: The postmortem findings of osteolysis and/or lymphocytic infiltration associated with eight clinically well- functioning, low wear devices (a total wear rate of <4 μm/yr) suggest there may be frequent, unappreciated femoral bone loss and local immunological response in patients with second-generation metal-on-metal hip implants. Compared with previous postmortem studies, our findings showed the extent of osteolysis was similar to that with metal-on-polyethylene articulations. [ABSTRACT FROM AUTHOR]

Background: When performing total hip arthroplasty without computer navigation, surgeons align the acetabular component with landmarks such as the plane of the operating table and the presumed position of the pelvis. In contrast, first-generation computer navigation systems rely on the pelvic anterior plane, defined by the anterior superior iliac spines and the pubic tubercle. We sought to study the effect of patient positioning on the tilt of the pelvis as measured in the pelvic anterior plane and its effect on cup alignment angle values. Methods: In forty patients, the supine pelvic anterior plane tilt angle was measured with use of computed tomographic scans made before and after total hip arthroplasty (Group A). In thirty other patients undergoing total hip arthroplasty, preoperative supine pelvic anterior plane tilt angle was measured with a computed tomographic scan and the preoperative standing pelvic anterior plane tilt angle was measured on a lateral radiograph (Group B). From these data, we used hip navigation planning software to develop a nomogram providing tilt-adjusted cup angles that would align the cup in a target range of 40° ± 10° of abduction and 15° ± 10° of anteversion. A third group of ninety-eight patients (Group C) then underwent total hip arthroplasty with computer navigation with use of our nomogram to provide tilt-adjusted values for cup alignment. Postoperative computed tomography scans were made to evaluate cup alignment, and the patients were followed for at least one year. Results: In Group A, the mean preoperative supine pelvic tilt angle (and standard deviation) was -8.9° ± 6.8° (forward rotation of the pelvis) and the mean postoperative angle was -10.9° ± 7.6° (p < 0.05). In Group B, the mean preoperative supine pelvic tilt angle was -10.4° ± 7.4° and the mean preoperative standing pelvic tilt angle was -5.0° ± 9.4° (p < 0.001). In the group of ninety-eight patients who underwent navigated total hip arthroplasty (Group C), there were no dislocations at one year of follow-up. Seventy-two patients underwent postoperative computed tomography scans; 99% of cup anteversion values and 97% of cup abduction values were in the target range. Conclusions: For navigation systems that rely on the pelvic anterior plane, cup alignment values can be converted to familiar target values with our nomogram with good accuracy and reproducibility. The next generation of navigation systems should be able to measure the pelvic tilt for each individual patient and automatically adjust alignment values. Level of Evidence: Diagnostic Level II. See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: Alternative bearings have been explored in an attempt to improve the longevity of total hip prostheses. A Food and Drug Administration (FDA)-approved clinical study of a nonmodular acetabular component consisting of a porous metal shell, compression-molded polyethylene, and a ceramic liner inlay was discontinued following reports of early failures. Methods: Between October 1999 and January 2003, 429 patients were enrolled in a prospective study to evaluate a cementless ceramic-on-ceramic total hip arthroplasty design (Hedrocel ceramic bearing cup; lmplex, Allendale, New Jersey). Two hundred and eighty-two patients (315 hips) were treated with the experimental acetabular implant and 147 patients (157 hips) were treated with an acetabular implant that consisted of the same porous shell but an all- polyethylene liner. Clinical data including a Harris hip score and responses to the Short Form-12 (SF-12) health survey were collected preoperatively and at twelve and twenty-four months postoperatively. Serial radiographs were made preoperatively; at six weeks, three months, six months, and twelve months postoperatively; and annually thereafter. Retrieval analysis was performed on all failed explanted components. Failure was defined as fracture or displacement of the ceramic liner out of the acetabular component. In addition, biomechanical testing was performed on unimplanted acetabular components and mechanically altered cups in an effort to recreate the mechanisms of failure. Finite element analysis was used to estimate stress and strain within the ceramic liner under extreme physiologic loading conditions. Results: The ceramic liner failed in fourteen of the 315 experimental acetabular components; all of the failures were at the ceramic-polyethylene interface. Patients with a body weight of >91 kg had a 4.76 times greater odds of the ceramic liner failing than those who weighed ≤91 kg. Retrieval analysis demonstrated stripe and rim wear with evidence of adhesive wear, indicating a potentially high-friction interaction at the articulation. Finite element analysis demonstrated that the forces on the ceramic liner in cups subjected to extreme loading conditions were insufficient to cause fracture. Biomechanical testing was unable to reproduce an initial ceramic liner displacement in vitro; however, when the ceramic liner was forcibly displaced prior to biomechanical testing, complete displacement and eventual fracture of the ceramic liner resulted. Conclusions: We hypothesized that the combination of a high patient body weight, an extensive range of motion, and subluxation of the femoral head led to high friction at the articulation between the femoral head and the rim of the liner, which initiated displacement of the ceramic liner. Subsequent normal gait led to further displacement of the liner in all of the fourteen failed components and eventually to ceramic fracture in twelve of the fourteen components. [ABSTRACT FROM AUTHOR]

Background: Previous recommendations for treatment of Morel-Lavallee soft-tissue degloving lesions have included open débridement with packing or delayed closure. The purpose of this study was to review the use of percutaneous drainage for the initial management of these lesions. Methods: Nineteen patients with a Morel-Lavallee lesion were managed with percutaneous drainage and débridement of the lesion within three days after the injury. Drainage was usually completed through two 2-cm incisions: one over the distal aspect of the lesion and one over the most superior and posterior extent of the lesion. A plastic brush was used to débride the injured fatty tissue, which was washed from the wound with pulsed lavage. A medium Hemovac drain was placed within the lesion and was removed when drainage was <30 mL over twenty-four hours. Results: Fifteen of the nineteen patients had surgery for an associated pelvic or acetabular fracture. Seven of the nine patients in whom a pelvic fracture was treated surgically had percutaneous fixation of the posterior part of the pelvic ring as well as treatment of the Morel-Lavallee lesion during the same operative setting. Fixation of the remaining two pelvic fractures and the six acetabular fractures was deferred until at least twenty-four hours after the drain was removed. Three of sixteen cultures of specimens taken from the wounds were positive. None of the patients with percutaneous fixation of the pelvis had wound complications. One wound required surgical exploration because of persistent drainage, but the culture was negative and the wound healed with no sequelae. No patient required débridement of skin and, at a minimum of six months, no deep infection had occurred. Conclusions: Early percutaneous drainage with débridement, irrigation, and suction drainage for the treatment of Morel-Lavallee lesions appears to be safe and effective. Percutaneous procedures for pelvic fixation were well tolerated by the small number of patients in this series, and open procedures appeared to be safe when performed in a delayed fashion. [ABSTRACT FROM AUTHOR]

Background: Total hip arthroplasty with cement remains a difficult procedure in patients with osteoarthritis secondary to developmental dysplasia of the hip as it is associated with high rates of aseptic loosening of the acetabular component. The purpose of the present study was to evaluate the rate of revision of the acetabular component in this group of patients and the variables that are associated with it. Methods: We retrospectively reviewed the records and radiographs of 292 hips in 206 patients who had undergone total hip arthroplasty with cement for the treatment of osteoarthritis secondary to developmental dysplasia of the hip. The average age of the patients at the time of the index procedure was 42.6 years, and the average duration of follow-up was 15.7 years (range, 2.2 to 31.2 years). Fourteen patients were lost to follow-up, and seven patients died from causes unrelated to surgery. A 22.25-mm head was used in all cases, and bone-grafting of the acetabulum was performed An forty-eight hips. Survival of the acetabular component was calculated with revision for aseptic loosening as the end point. Individual survival rates based on age, component type, previous surgery, and annual polyethylene wear also were calculated. Results: The most common reason for revision was aseptic loosening of the acetabular component, which led to 87.2% of the revision procedures. The overall rate of survival of the acetabular component was 90.6% at ten years and 63% at twenty years. A higher rate of acetabular revision was noted in association with previous acetabular surgery, the offset-bore cup, younger age, and accelerated polyethylene wear (p < 0.05 for all comparisons). Conclusions: Aseptic loosening of the acetabular component affects the longevity of total hip replacements in patients with osteoarthritis secondary to developmental dysplasia of the hip. The present study identified the risk factors associated with the long-term survival of the acetabular component in this group of patients. [ABSTRACT FROM AUTHOR]

The article focuses on the management of bone loss in acetabular revision. Revision of cemented acetabular components is most commonly performed because of aseptic loosening with migration of the component. The most challenging aspect of acetabular revision is the management of bone loss compromising implant fixation and stability. Revision may be indicated for an asymptomatic patient who has progressive osteolysis, severe wear, or bone loss that could compromise a future reconstruction. Contra indications for revision of the acetabular component include severe bone loss precluding allograft fixation or implant fixation, uncontrolled infection, or medical comorbidities that preclude surgery.

This prospective study was performed to examine the results of total hip arthroplasty with a tapered uncemented femoral component with and without hydroxyapatite coating in a matched-pair group of patients. Since our original publication in 1996, no femoral component was revised in either group. After a mean clinical and radiographic follow-up of 9.8 years, all femoral components were stable, with no evidence of progressive radiolucency or osteolysis. Ten acetabular components were revised because of aseptic loosening and wear. Our study demonstrated no clinical or radiographic advantage, during the first decade after implantation, to the use of hydroxyapatite on this design of femoral component in primary total hip arthroplasty. Level of Evidence: Therapeutic study, &dLevel II-1line; (prospective cohort study). See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to update the results of a prospective, single-surgeon series of primary Charnley total hip arthroplasties performed with cement. This investigation is one of the first studies in which hips treated with total hip arthroplasty with cement were followed for a minimum of thirty years. Twenty-seven patients (thirty-four [10.3%] of the hips in the initial study group) were alive at a minimum of thirty years postoperatively. These patients served as the focus of the present study. Revision because of aseptic loosening of the acetabular component was performed in 7.3% (twenty-three) of the hips from the original study group (excluding those revised because of infection or dislocation) and 26% (eight) of the hips in the living cohort. Revision because of aseptic loosening of the femoral component was performed in 3.2% (ten) of the hips from the original study group (excluding those revised because of infection or dislocation) and 10% (three) of the hips in the living patients. Since the twenty-five-year review, three hips were revised (one because of acetabular loosening, one because of femoral loosening, and one because of instability). This end-result study demonstrated the remarkable durability of cemented Charnley total hip replacements over a span of three decades, with 88% of the original prostheses intact at the time of the final follow-up or at the patient's death. Level of Evidence: Therapeutic study, &dLevel IVline; (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Background: A common clinical scenario encountered by an orthopaedic surgeon is a patient with a secure cementless acetabular shell and a failed polyethylene liner. One treatment option is to cement a new liner into the fixed shell. The purpose of this study was to evaluate technical variables to improve the mechanical strength of such cemented liner constructs. Methods: The contributions of shell texturing, liner texturing, and cement mantle thickness (between the liner and the shell) were evaluated by comparing torsional strength (among nine groups of constructs) and lever-out strength (among eight groups of constructs). Results: Failure almost always occurred at the cement-liner interface. The two exceptions (failure at the shell-cement interface) occurred with a polished, untextured shell with no screw-holes. This finding indicates that if a shell has existing texturing (such as holes), further intraoperative scoring of the shell is unnecessary, but some sort of texturing is necessary to avoid construct failure at the shell-cement interface. Textured liners had significantly (α = 0.05) greater torsional and lever-out strength than untextured liners. The greatest construct strength occurred when liner grooves were oriented so as to oppose the applied loading. A 4-mm-thick cement mantle resulted in slightly greater torsional strength than a 2-mm-thick cement mantle, and a 2-mm-thick cement mantle resulted in considerably greater lever-out strength than a 4-mm-thick cement mantle, but these differences were not significant. Conclusions: When cementing a liner into a well-fixed shell, a surgeon should ensure that both the shell and the liner are textured, as interdigitation of the cement with the shell and the liner is crucial to the mechanical strength of this construct. [ABSTRACT FROM AUTHOR]

Background: Acetabular revision in patients with rheumatoid arthritis is often difficult because of the poor quality and quantity of the acetabular bone stock. The purpose of this study was to evaluate the midterm clinical and radiographic outcomes of acetabular revision with use of an impaction bone-grafting technique and a cemented polyethylene cup. Methods: Thirty-five consecutive acetabular revisions were performed with impaction bone-grafting and use of a cemented cup in twenty-eight patients with rheumatoid arthritis. The average age at the revision was fifty-seven years. The minimum duration of follow-up of all reconstructions that were still functioning or that were followed until the time of death was three years (mean, 7.5 years; range, three to fourteen years). No patient was lost to follow-up, but five patients (six hips) died before the time of the review. The acetabular bone defects were classified as cavitary in twelve hips and as combined segmental-cavitary in twenty-three. Results: The five patients (six hips) who died had been doing well at the time of their latest follow-up. Of the remaining patients, six (six hips) had a repeat revision. The average Harris hip score of the living patients with a surviving implant at the time of follow-up was 82 points, and there was no or only mild pain in twenty-one of the twenty-three hips. Radiographic analysis of all twenty-nine hips that had not been revised showed loosening in one hip and a nonprogressive radiolucent line in one zone in two others. Kaplan-Meier analysis demonstrated a prosthetic survival rate, with aseptic loosening as the end point, of 90% at eight years. Conclusion: Acetabular revision with impaction bone-grafting and a cemented cup in patients with rheumatoid arthritis had acceptable results at an average of 7.5 years postoperatively. Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete... [ABSTRACT FROM AUTHOR]

Background: Eccentric rotational acetabular osteotomy for the operative treatment of acetabular dysplasia consists of a spherical but eccentric osteotomy and rotation of the acetabulum that moves the center of rotation of the head of the femur medially and distally. No bone graft is needed. The reorientation of the acetabular fragment not only improves acetabular coverage but also restores the center of rotation of the subluxated hip. The purpose of this paper was to describe eccentric rotational acetabular osteotomy for the treatment of acetabular dysplasia and to evaluate its clinical and radiographic outcomes.Methods: We performed this procedure consecutively in 132 hips in 126 patients with dysplasia of the hip. Eighteen hips had no osteoarthritis, fifty-three had early osteoarthritis, and sixty-one had advanced osteoarthritis. Seven patients were male, and 119 were female. The average age was 36.5 years at the time of the index operation, and the average duration of follow-up was 7.5 years. Twenty-three hips in twenty-two patients were also treated with intertrochanteric valgus osteotomy to further improve joint congruency at the time of the acetabular osteotomy.Results: The average preoperative Harris hip score of 71 points improved to an average score of 89 points at the time of the latest follow-up. The average center-edge angle improved from 0 to 36 . An apparent change in the stage of the arthritis was observed in seven hips (5%), one of which had had early-stage disease and six of which had had advanced disease preoperatively.Conclusions: Eccentric rotational acetabular osteotomy appears to be a good treatment option for young patients with either early or advanced hip osteoarthritis secondary to dysplasia. [ABSTRACT FROM AUTHOR]

The article focuses on improving the accuracy of acetabular component orientation. The use of larger femoral head sizes in primary total hip arthroplasty has increased in recent years with the introduction of alternative bearings and reduced short-tern dislocation. Many factors can negatively impact acetabular component positioning.