The Journal of Arthroplasty - Articles in Press

Functional Outcomes for 2 Years Comparing Hip Resurfacing and Total Hip Arthroplasty - Corrected Proof

The Alberta Hip Improvement Project — 2012-01-30

Abstract: This prospective observational study of 499 patients with hip resurfacing and 255 patients with total hip arthroplasty compared outcomes for 2 years. We used propensity scores to identify matched cohorts of 118 patients with hip resurfacing and 118 patients with total hip arthroplasty. We used these cohorts to compare improvements in the Western Ontario and McMaster University (WOMAC) osteoarthritis index and Medical Outcomes Short-Form 36 physical function component (SF-36 PF) scores at 3 months and at 1 and 2 years postsurgery. Both groups demonstrated significant improvements from baseline in WOMAC and SF-36 PF. Improvements in SF-36 PF were greater for patients with hip resurfacing than for patients with total hip arthroplasty 1 and 2 years postsurgery; improvements in WOMAC were similar for both groups. The clinical significance of this observation needs further investigation.

Custom-Fit Total Knee Arthroplasty: Our Initial Experience in 32 Knees - Corrected Proof

Kamal Bali, Peter Walker, Warwick Bruce — 2012-01-30

Abstract: We share our initial experience of total knee arthroplasty (TKA) using customized cutting block technology in 32 TKAs from May 2010 to March 2011. Ten of these patients had prior TKA done on the other side using conventional or navigation-assisted TKA. Customized cutting blocks were generated for each of the knee using preoperative magnetic resonance imaging of knee and long-leg weight-bearing radiographs. At 6 weeks, long-leg radiographs were obtained to evaluate the coronal alignment. There were no adverse intraoperative events. Twenty-nine of the 32 knees had a mechanical axis restored to within 3°° of neutral. Of 10 patients with prior TKA without custom-fit technology, the mean blood loss and the mean skin-to-skin time was found to be lower in knees that had undergone custom-fit TKA. We conclude that this technology can be safely used in most of the cases of osteoarthritis.

Total Knee Arthroplasty in Osteopetrosis Using Patient-Specific Instrumentation - Corrected Proof

Stephanie W. Mayer, Kevin T. Hug, Benjamin J. Hansen, Michael P. Bolognesi — 2012-01-30

Abstract: Osteopetrosis is an uncommon endocrine disease characterized by defective osteoclast resorption of bones. This causes a hard, sclerotic, and brittle bone throughout the skeleton. Fractures and unforgiving subchondral bone are common in this condition, both of which can lead to osteoarthritis. Total knee arthroplasty is often the treatment of choice but presents challenges due to the hard and sclerotic bone present throughout the metaphysis and diaphysis of the femur and the tibia. We present a case of knee osteoarthritis in a patient with osteopetrosis who underwent total knee arthroplasty using patient-specific instrumentation. This technique eliminates intramedullary alignment and minimizes drilling, reaming, and saw passes, making it attractive in the setting of diseases such as osteopetrosis to decrease operative time and potential complications.

Effect of Femoral Component Design on Patellofemoral Crepitance and Patella Clunk Syndrome After Posterior-Stabilized Total Knee Arthroplasty - Corrected Proof

Benjamin M. Frye, Mark W. Floyd, Dahn C. Pham, John J. Feldman, Brian R. Hamlin — 2012-01-30

Abstract: The purpose of this study was to determine if recent changes to the femoral component of a particular posterior-stabilized total knee prosthesis would affect the incidence of postoperative patellofemoral crepitance and patella clunk syndrome. One hundred eight total knee arthroplasties were performed with the conventional design; 136 were performed after the femoral component was changed. Complications were compared between the groups with an average follow-up of 17.7 months and 12.4 months, respectively. Thirteen knees with the conventional design (12%) were found to have patellofemoral complications; no complications were noted with the new design (P < .0001). Femoral components with a deep trochlear groove and smooth transition of the intercondylar box appear to better accommodate any peripatellar fibrous nodule that may form after total knee arthroplasty.

Factors Affecting the Postoperative Limb Alignment and Clinical Outcome After Oxford Unicompartmental Knee Arthroplasty - Corrected Proof

Seung-Ju Kim, Ji-Hoon Bae, Hong Chul Lim — 2012-01-30

Abstract: We evaluated the postoperative mechanical axis deviation and clinical outcome according to bearing size, femoral component position, and tibial resection angle after unicompartmental knee arthroplasty (UKA). A total of 104 patients with 124 knees underwent Oxford phase 3 UKA. The overall changes in mechanical axis deviation and tibiofemoral angle were significantly different according to bearing size (P = .001 and < .001), but they were not significantly different according to the tibial resection angle and femoral component position. The postoperative mechanical axis fell into the zone C or zone 2 in 108 knees (87%) and into the zone 3 or zone 4 in 16 cases (13%). One hundred eight cases, which had the mechanical axis passing the zone C or zone 2, did not show any progression of arthritis. Limb alignment is a function of the thickness of the bearing rather than alignments of femoral and tibial implant.

Increased Operating Room Time in Patients With Obesity During Primary Total Knee Arthroplasty: Conflicts for Scheduling - Corrected Proof

Naomi E. Gadinsky, Jacob B. Manuel, Stephen Lyman, Geoffrey H. Westrich — 2012-01-30

Abstract: Obesity is associated with increased complications related to total knee arthroplasty (TKA), but the relationship between body mass index (BMI) and operating room time during TKA is unknown. A total of 454 unilateral primary TKAs (2005-2009) were reviewed and categorized by BMI (normal weight, 18.5-25 kg/m2; overweight, 25-30 kg/m2; obese class I, 30-<35 kg/m2; class II, 35-40 kg/m2; class III, >40 kg/m2). Intraoperative time measurements (total room time, anesthesia induction time, tourniquet time, closing time, surgery time) were compared across the BMI groups. Comparing normal weight to obese class III, time differences were significant in total room time (24 minutes, P < .01), surgery time (16 minutes, P < .01), tourniquet time (7.5 minutes, P < .01), and closure time (8 minutes, P < .01). Armed with this information, BMI can be used to better allocate operating room time for TKA.

Design, Implementation, and Comparison of Methods for Collecting Implant Registry Data at Different Hospital Types - Corrected Proof

2012-01-30

Abstract: Practical issues surrounding the official establishment of a national arthroplasty registry in the United States remain. The purpose of this study was to compare compliance and accuracy rates associated with 3 methods for voluntarily collecting implant registry data at 3 different hospital types. Methods examined included (1) scannable paper forms, (2) online forms comprising keypunching for implant data input, and (3) the same electronic form but incorporating barcode scanning for implant data entry. Overall compliance was low (930/1761; 52.8%) and decreased with each successive data collection phase. Total accuracy rate was 62.5% (578/925) and varied significantly among sites (P < .001). Even with relatively simple reporting systems, compliance was poor. This emphasizes the need for direct surgeon involvement, strict oversight, and a feedback system to ensure validity, particularly if a volunteer-based system is used.

Preoperative Knee Stiffness and Total Knee Arthroplasty Outcomes - Corrected Proof

Mitch Winemaker, Wael A. Rahman, Danielle Petruccelli, Justin de Beer — 2012-01-30

Abstract: A retrospective case-control study was conducted to evaluate 1-year total knee arthroplasty (TKA) outcomes among preoperative stiff knees, range of motion (ROM) 80° or less, compared with nonstiff preoperative knees, ROM 100° or greater. A total of 134 stiff knee cases were compared with a matched cohort of 134 non–stiff knee controls. Knee Society Score and Oxford Knee Score change scores from baseline to 1 year were similar between the groups. Stiff knees experienced a significantly greater mean improvement in ROM from baseline to 1 year (30.8° ± 18.8°) as compared with nonstiff knees (1.1° ± 12.8°) (P < .0001). Although ultimate ROM of a TKA can be restricted secondary to preoperative stiffness, improvements in outcomes and ROM are not affected. We conclude that progression of stiffness should not in and of itself lead to earlier intervention of TKA in most cases.

Cementless Acetabular Fixation in Patients 50 Years and Younger at 10 to 18 Years of Follow-Up - Corrected Proof

2012-01-24

Abstract: The purpose of the study was to evaluate the 10- to 18-year follow-up of cementless acetabular fixation in patients 50 years and younger. We retrospectively reviewed a consecutive group of 118 patients (144 hips) in whom primary total hip arthroplasty had been performed by 2 surgeons using a cementless acetabular component. Two (1.4%) cementless acetabular components were revised because of aseptic loosening. Twenty-four hips (16.7%) were revised for any mechanical failure of the acetabular component mostly related to acetabular liner wear and osteolysis. The average linear wear rate was 0.19 mm per year, which was higher than our previous reports with cemented acetabular fixation. The fiber mesh ingrowth surface of the cementless acetabular component in this study was superior to cemented acetabular components in terms of fixation. However, the high rates of wear and osteolysis have led to poor overall acetabular component construct survivorship.

Bipolar Sealing in Revision Total Hip Arthroplasty for Infection: Efficacy and Cost Analysis - Corrected Proof

2012-01-24

Abstract: Saline-coupled bipolar sealing has shown mixed results in primary arthroplasty. However, this technology has not been studied in infected revision total hip arthroplasty (THA), where morbidity is higher and conventional methods of blood management, such as cell salvage, often cannot be used. This case-matched study of 76 consecutive revision THA for infection included an experimental bipolar sealing group and a control group of conventional electrocautery. Groups were matched for gender, body mass index, American Society of Anesthesiologists classification, and surgery type. Total blood loss, intraoperative blood loss, and perioperative hemoglobin drop were significantly less in the experimental group. In addition, operative time was significantly shorter in the experimental group, which translated into gross savings approximately equal to the cost of the device. The decreases in total blood loss and perioperative hemoglobin decline, along with financial savings, may support the use of bipolar sealing in infected revision THA.

The 6-Year Migration Characteristics of a Hydroxyapatite-Coated Femoral Stem: A Radiostereometric Analysis Study - Corrected Proof

2012-01-24

Abstract: A prospective cohort of 30 patients undergoing primary total hip arthroplasty for treatment of osteoarthritis was enrolled in a study to characterize the migration behavior of a clinically successful cementless stem. At 6 years, the mean subsidence of the stem was 0.63 mm (range, −0.33 to 3.68 mm); the mean rotation into retroversion was 1.41° (range, −1.33° to 7.48°). No stems had additional subsidence of more than 0.25 mm between 6 months and 6 years. The resultant mean subsidence between 2 and 6 years was 0.03 mm, which is below the limit measurable by radiostereometric analysis. The data demonstrate that subsidence of this cementless stem occurs within the first 6 months, after which there is persistent stabilization.

Patient Perception of Physician Reimbursement in Elective Total Hip and Knee Arthroplasty - Corrected Proof

2012-01-16

Abstract: The purpose of this study was to evaluate patient perception of orthopedic surgeon reimbursement for total hip (THA) and knee (TKA) arthroplasty. A total of 1120 consecutive patients were asked what they believed a surgeon should be paid for performing THA and TKA. Patients were then asked to estimate what Medicare actually reimbursed for each of these procedures. On average, patients thought that surgeons should receive $14 358 for THA and $13 332 for TKA. Patients estimated actual Medicare reimbursement to be $8212 for THA and $7196 for TKA. Most of the patients stated that Medicare reimbursement was “much lower” than what it should be. Many patients commented that given this discrepancy, surgeons may drop Medicare, which may decrease access to quality hip and knee arthroplasties.

Advanced Age and Comorbidity Increase the Risk for Adverse Events After Revision Total Hip Arthroplasty - Corrected Proof

2012-01-16

Abstract: With the institution of quality-assurance parameters in health care, physicians must accurately measure and report the true baseline rates of adverse events (AEs) after complex surgical interventions. To better quantify the risk of AEs for revision total hip arthroplasty (THA), we divided a cohort of 306 patients (322 procedures) into age groups: group I (<65 years, n = 138), group II (65-79 years, n = 119), and group III (≥80 years, n = 65). Ninety-day rates of major AE were 9%, 19%, and 34% in the groups, respectively. Group III had an increased chance of experiencing major AE compared with groups I and II. Age and Charlson Comorbidity Index independently predicted major complications, whereas body mass index, sex, and type of revision did not.

Improving Acetabular Cup Orientation in Total Hip Arthroplasty by Using Smartphone Technology - Corrected Proof

Frank M. Peters, Richard Greeff, Neal Goldstein, Chris T. Frey — 2012-01-16

Abstract: Acetabular cup placement in total hip arthroplasty is often difficult to assess, especially in the lateral position and using the posterior approach. Conventional techniques and computer-assisted surgery are the 2 most popular methods for proper placement of the acetabular cup in Lewinnek's safe zone of orientation (anteversion 15° ± 10° and lateral inclination 40° ± 10°). We developed a system that uses the accelerometer and camera function of the iPhone. A level indicator application and protractor application were downloaded to the iPhone and used to improve acetabular cup placement. This system has proven to be accurate and quick. Our series of 50 prospective cases showed good results with all our acetabular cups being placed within a narrow range in the safe zone and with less than 5% difference between the preoperative, intraoperative, and postoperative acetabular inclinations.

Low Rates of Heterotopic Ossification After Resurfacing Hip Arthroplasty With Use of Prophylactic Radiotherapy in Select Patients - Corrected Proof

2012-01-16

Abstract: Recent reports have noted higher rates of heterotopic ossification (HO) with surface replacement arthroplasty (SRA) than with traditional total hip arthroplasty in the absence of postoperative HO prophylaxis. This study reports rates and grades of HO in 44 SRA patients with at least 1 year of follow-up. Heterotopic ossification prophylaxis was used in 32 (73%) of 44 cases. Heterotopic ossification prophylaxis consisted of radiotherapy (22/32), nonsteroidal anti-inflammatory drugs (8/32), or both (2/32). One case of clinically significant HO was documented in the no-prophylaxis group. This strategy of selective HO prophylaxis in patients felt by orthopedic surgeons to be at high risk of HO resulted in low rates of clinically relevant HO after SRA (1/44, 2.3%). Further study is needed to establish optimal selection criteria for HO prophylaxis after SRA.

Periacetabular Cortical and Cancellous Bone Mineral Density Loss After Press-Fit Cup Fixation: A Prospective 7-Year Follow-Up - Corrected Proof

2012-01-09

Abstract: The impact of total hip arthroplasty on strain adaptive bone remodeling has been extensively analyzed by dual-energy x-ray absorptiometry. In this study, we present a prospective computed tomography–assisted study of periacetabular cortical and cancellous bone mineral density (in milligrams of calcium hydroxyapatite [CaHA] per milliliter, or mgCaHA/mL) changes 10 days and 1, 3, and 7 years after press-fit cup implantation for 38 hips in vivo. Cancellous bone mineral density decreased by Ø −63% ventral and Ø −85% dorsal to the cup; cortical bone mineral density, by Ø −22% ventral and Ø −18% dorsal to the cup. The presented periacetabular strain adaptive bone mineral density data are the most extensive of the current literature. Even the measured extensive cancellous bone mineral density loss was thus far of no clinical relevance because all cups showed radiographic signs of stable ingrowth.

Abductor Dysfunction and Related Sciatic Nerve Palsy, a New Complication of Metal-on-Metal Arthroplasty - Corrected Proof

Walter B. Beaver, Thomas K. Fehring — 2012-01-09

Abstract: The optimal bearing for use in young patients with hip arthritis remains elusive. Current options include metal–on–cross-linked polyethylene, ceramic–on–cross-linked polyethylene, ceramic on ceramic, and metal on metal. Each of these bearing couples has advantages and disadvantages. Metal-on-metal designs allow the use of large heads that decrease impingement and improve stability. This fact has made this bearing an attractive option for surgeons and patients alike. This case report will illustrate a severe adverse reaction to metal debris with necrosis of soft tissues and subsequent damage to the sciatic nerve.

Comparison of Arthroplasty Trial Publications After Registration in ClinicalTrials.gov - Corrected Proof

Holly N. Smith, Mohit Bhandari, Nizar N. Mahomed, Meryam Jan, Rajiv Gandhi — 2012-01-09

Abstract: In 2005, the International Committee of Medical Journal Editors established a mandatory trial registration before study enrollment for publication in member journals. Our primary objective was to evaluate the publication rates of arthroplasty trials registered with ClinicalTrials.gov (CTG). We further aimed to examine the consistency of registration summaries with that of final publications. We searched CTG for all trials related to joint arthroplasty and conducted a thorough search for publications resulting from registered closed trials. Of 101 closed and completed trials, we found 23 publications, for an overall publication rate of 22.8%. Registration of arthroplasty trials in CTG does not consistently result in publication or disclosure of results. In addition, changes are frequently made to the final presentation of the data that are not reflected in the trial registry.

Repeat 2-Stage Exchange for Infected Total Hip Arthroplasty: A Viable Option? - Corrected Proof

2012-01-09

Abstract: We investigated whether performing a repeat 2-stage exchange eradicates infection in patients who previously underwent 2-stage treatment for an infected total hip arthroplasty. We identified 15 patients who had failed a 2-stage total hip arthroplasty and underwent a planned repeat 2-stage between 2000 and 2009. Of the 15 patients, 8 were treated with a complete 2-stage procedure, whereas the remaining 7 patients were treated only with a first-stage resection of the infected implant. Of the 8 patients who underwent complete 2-stage exchange, 1 died because of in-hospital complications, and 1 had a recurrent infection. Repeat infection is highly associated with resistant organisms, obesity, and poor patient health. Of the 7 patients who underwent resection without reimplantation, 3 had a recurrent infection. Our data suggest that if infection can be adequately controlled after repeat resection of the joint prosthesis, reimplantation is a reasonable option.

Letter to the Editor - Corrected Proof

Sulaiman Alazzawi, Aiman Khunda, Shah Jehan — 2012-01-09

We read the article “Short-Term Coagulation Complications Following Total Knee Arthroplasty” with great interest, and we would like to congratulate Dushey et al on their work on validation of patient-reported coagulation complications after total knee surgery.

Mental Health and Outcomes in Primary Total Joint Arthroplasty - Corrected Proof

Carlos J. Lavernia, Jose C. Alcerro, Larry G. Brooks, Mark D. Rossi — 2012-01-09

Abstract: A consecutive series of 640 total joint arthroplasty patients was interviewed before surgery and at a minimum of 2 years following surgery. Statistical analyses were conducted to examine the effect of psychological distress and other patient characteristics on outcomes (Western Ontario and McMaster Universities Osteoarthritis Index, Short Form 36, and Quality of Well-Being index). Before and after surgery, distressed subjects had significantly lower scores than nondistressed subjects for most dependent measures (P range, .05 ≤ .001). All mean outcomes improved by follow-up in both groups (P ≤ .001) except mental health scores of nondistressed subjects. Stepwise regression analysis found that low baseline mental health score, non-Hispanic ethnicity, and fewer years since procedure were the strongest predictors of worse Western Ontario and McMaster Universities Osteoarthritis Index scores at follow-up. Although the magnitude of improvement is similar to nondistressed subjects, distressed patients do not achieve comparable functional and psychosocial outcomes.

Costs Related to Hip Disease in Patients Eligible for Total Hip Arthroplasty - Corrected Proof

Ola Rolfson, Oskar Ström, Johan Kärrholm, Henrik Malchau, Göran Garellick — 2012-01-03

Abstract: This study was designed to estimate direct and indirect costs incurred by hip disease in patients eligible for total hip arthroplasty (THA). Before THA, 2635 patients completed a questionnaire regarding the use of resources because of their hip disease. Costs were assigned using official statistical sources or market prices. Annual costs amounted to US$ 7666 per patient. In a regression analysis, higher annual costs were associated with working age, female gender, comorbidity, and operation waiting time more than 90 days (P < .005). The burden of disease for THA candidates is extensive, where loss of productivity is the principal cost. Long wait for surgery is associated with increased costs. This study provides baseline cost data, which will be useful for further health economic analyses and could provide guidance for health care decision makers.

In Reply: - Corrected Proof

Craig Dushey, Geoffrey Westrich — 2012-01-03

Thank you for your inquiry. In all cases, a small number of patients who reported complications on our CERT survey could not be contacted to verify those complications despite multiple attempts. These patients were therefore subtracted from the denominator.

Total Hip Arthroplasty in High Dislocated and Severely Dysplastic Septic Hip Sequelae - Corrected Proof

Kyung-Soon Park, Taek-Rim Yoon, Eun-Kyoo Song, Jong-Keun Seon, Keun-Bae Lee — 2012-01-03

Abstract: The authors analyzed a consecutive series of 20 total hip arthroplasties performed using a cementless conical stem with shortening osteotomy combined with greater trochanter transfer in cases with a highly dislocated hip secondary to sequelae of a septic hip in childhood. Mean patient age was 47.3 years and the mean follow-up period was 3.4 years. An acetabular metal cup was inserted in 5 cases, and only a liner was inserted after cementing in 15 cases. Mean Harris hip score improved from 42.4 preoperatively to 84.2 at final follow-up. Mean leg lengthening was 36.5 mm, and time to greater trochanter union was 3.72 months. No complete radiolucent line of thickness >2 mm was observed in any case. These surgical methods produced satisfactory clinical and radiological results.

Femoral Stem Fracture and In Vivo Corrosion of Retrieved Modular Femoral Hips - Corrected Proof

2011-12-30

Abstract: A series of 78 retrieved modular hip devices were assessed for fretting and corrosion. Damage was common at both the head-neck junction (54% showing corrosion; 88% showing fretting) and at the stem-sleeve junction (88% corrosion; 65% fretting). Corrosion correlated to in vivo duration, patient activity, and metal (vs ceramic) femoral heads but did not correlate to head carbon content. Femoral stem fatigue fracture was observed in seven retrievals; all had severe corrosion, were under increased stress, and were in vivo longer than the non-fractured cohort. This study emphasizes the potential for stem fracture when small diameter femoral stems with large offsets are used in heavy and active patients. Designs which reduce fretting and corrosion in modular implants is warranted as patients demand longer lasting implants.

The Minimum 10-Year Results of a Second-Generation Cementless Acetabular Shell With a Polished Inner Surface - Corrected Proof

2011-12-30

Abstract: The purpose of this prospective study was to evaluate the minimum 10-year outcomes and survivorship of the Reflection shell with a polished inner surface and an improved locking mechanism. Three hundred sixty-three total hip replacements with a mean follow-up of 11.6 years (range, 10.0-15.1) were evaluated. The mean Harris Hip and WOMAC scores at last follow-up were 87 and 77, respectively. Four cups were revised: 2 for infection and 2 for aseptic loosening. Thirteen cases underwent liner exchange for wear. Radiographic review of remaining cups identified 8.8% with identifiable peri-acetabular osteolysis and no cases of loosening. The overall 10- and 15-year Kaplan-Meier survivorship was 94% and 90% for the total hip arthroplasty system while the survivorship of the shell remained 99.4% at 15 years.

The Effect of Patellar Replacement Technique on Patellofemoral Complications and Anterior Knee Pain - Corrected Proof

2011-12-26

Abstract: Routine patella replacement with total knee arthroplasty has not been universally adopted because of associated patellofemoral complications such as anterior knee pain (AKP). In the proposed technique, the articular surface of the lateral facet of the patella is excised to the depth of the subchondral bone, and the medial facet is then cut parallel to the anterior surface. We evaluated any correlation between various radiographic parameters and AKP in 100 consecutive fixed-bearing posterior-stabilized total knee arthroplasties. There were no cases of fracture, avascular necrosis, subluxation, dislocation, patellar baja, or overstuffing of the patella. Anterior knee pain was present in 11% of cases, and no cases were severe or disabling. There were no correlations between AKP, range of motion, patellar size and shape, and any of the radiographic parameters.

The Validity of Self-Report as a Technique for Measuring Short-Term Complications After Total Hip Arthroplasty in a Joint Replacement Registry - Corrected Proof

2011-12-26

Abstract: This study evaluated concordance between self-reports and surgeon assessments of short-term complications. A total of 3976 primary total hip arthroplasty patients consented for an institutional registry (5/2007-12/2008); 3186 (80.1%) completed a 6-month survey; 137 (4.4%) reported deep venous thrombosis, pulmonary embolism, major bleeding, fracture, or dislocation. Patients reporting complications were called. Positive predictive values and 95% confidence intervals (95% CI) for patient self-report were measured, using surgeon assessment for comparison: pulmonary embolism, 88.9% (95% CI, 78.4%-99.4%); dislocation, 81.1% (95% CI, 75.9%-86.5%); fracture, 73.7% (95% CI, 63.8%-83.5%); deep venous thrombosis, 69.7% (95% CI, 61.9%-77.5%); major bleeding, 32.0% (95% CI, 19.4%-44.5%); any bleeding, 88.0% (95% CI, 75.3%-99.9%). Of 97 confirmed complications, 64.95% presented to outside institutions. Registry data on self-reported complications may overcome limitations of traditional methods, but data should be interpreted cautiously. Concordance was high for PE and dislocation but low for major bleeding.

Effectiveness of False Profile Radiographs in Detection of Pelvic Discontinuity - Corrected Proof

2011-12-26

Abstract: Pelvic dissociation is a rare but serious potential complication of total hip arthroplasty. The purpose of this study is to evaluate the effectiveness of the false profile view compared with traditional radiographs in detecting pelvic dissociation. Ten cadaver pelves were skeletonized, and noncemented acetabular hip arthroplasty components were implanted. Anteroposterior, lateral, iliac oblique, and false profile radiographs were obtained before and after creating pelvic dissociations and analyzed in a blinded fashion. The sensitivity of the false profile view for detecting pelvic dissociation was 79% (confidence interval, 70-86), which was greater than the sensitivity for anteroposterior and lateral views. This difference was statistically significant. False profile views are a potentially valuable addition to the traditional radiographic evaluation of pelvic discontinuity in hip arthroplasty.

In reply - Corrected Proof

Brett Russell Levine, Michael B. Ellman — 2011-12-26

We appreciate the opportunity to respond to comments brought forth by Dr Abbott Kagan II regarding our case report recently published online in the Journal of Arthroplasty, “Fracture of the Modular Femoral Neck Component in Total Hip Arthroplasty.” The article reports the complicated course of a patient who sustained a modular femoral neck fracture with subsequent revision procedures to achieve a satisfactory result. In the article, we refer to these procedures as “unnecessary.” In his response, Dr Kagan questions the appropriateness of our verbiage in the report, stating “I do not know that the authors were in a position to determine the ‘appropriateness’ of the procedures as they were not the treating surgeon. Is every failed surgical procedure to be judged unnecessary?” and goes on to cite the American Academy of Orthopaedic Surgeons (AAOS) Standards of Professionalism to support his response. We would like to thank Dr Kagan for his response to our study and willingly encourage the opinions of other professionals in our field. In addition, the senior author (B.L.) would like to apologize for any confusion in reading our article and would like to clarify that the word unnecessary was directed toward the failure of the implant and not on how the subsequent surgeries were performed. We would never assume or judge the appropriateness of surgery or pretend to understand what might have taken place while another surgeon was operating. In rereading the article, I can see where this verbiage could be taken the wrong way and detract from the actual message of the article.

Variable Expression and Incomplete Penetrance of Developmental Dysplasia of the Hip: Clinical Challenge in a 71-Member Multigeneration Family - Corrected Proof

2011-12-19

Abstract: Developmental dysplasia of the hip is a crippling condition that affects children and adults. Identical twin studies support a strong causative genetic component. Although clinical tests for newborns can detect gross malformations, it is the subtle malformations that are often not detected, resulting in early onset osteoarthritis of the hip in adults. As a first step in identifying the causative mutation, we have recruited the largest documented affected family with 71 members spanning generations. Clinical and radiographic signs of developmental dysplasia of the hip are described, and the diagnostic challenge of identifying affected family members is discussed. Variable expression of disease allele is evident in several members of the family and greatly contributes to the diagnostic challenge facing clinicians.

A Pilot Study of Computed Tomography–Detected Asymptomatic Pulmonary Filling Defects After Hip and Knee Arthroplasties - Corrected Proof

2011-12-19

Abstract: We asked what the incidence of asymptomatic filling defects is on routine multidetector computed tomography (MDCT) in primary hip (total hip arthroplasty [THA]) and knee arthroplasties (TKA) patients. We prospectively performed MDCT scans on the first postoperative day for THA (n = 21)/TKA (n = 27). Patients underwent routine postoperative care, and data were collected for symptoms such as tachycardia or shortness of breath. More patients undergoing TKA had positive computed tomography scans than those undergoing THA: 11 (41%) vs 1 (5%), respectively. All patients diagnosed with a filling defect were discharged from the hospital without treatment of symptomatic pulmonary embolism. Our study demonstrates a high rate of abnormal MDCT early after lower extremity arthroplasty, the clinical importance of which may be benign.

Two-Stage Cementless Revision of Late Total Hip Arthroplasty Infection Using a Premanufactured Spacer - Corrected Proof

Daniel R.P. Neumann, Thomas Hofstaedter, Corina List, Ulrich Dorn — 2011-12-19

Abstract: We observed 44 patients with 2-stage revisions for septic hip prostheses. We used a uniform protocol consisting of the implantation of a preformed spacer (interval 12-26 weeks), specific systemic antibiotic therapies, and cementless total hip arthroplasty at time of reimplantation. The minimum follow-up was 36 months (mean, 67 months; range, 36-120 months). During the spacer period, we observed 4 dislocations and 2 fractures leading to a resection arthroplasty interval before reimplantation in 5 cases. In one patient, reinfection was diagnosed 12 months after reimplantation. The Harris hip score increased from a preoperative mean of 39 to 90 at a mean follow-up of 67 months after reimplantation.

The Influence of Sterilization Method on Articular Surface Damage of Retrieved Cruciate-Retaining Tibial Inserts - Corrected Proof

Matthew T. Greulich, Marcel E. Roy, Leo A. Whiteside — 2011-12-19

Abstract: This observational study was designed to determine the importance of sterilization method and insert thickness as predictors of articular damage of cruciate-retaining polyethylene components used in total knee arthroplasty. Ninety-nine explanted tibial inserts were evaluated for surface damage. Severe damage modes were observed in 36 of 52 of γ-irradiated inserts but none of those sterilized by ethylene oxide. Articular damage significantly correlated to time in vivo but not to insert thickness. Inserts sterilized by ethylene oxide gas in gas-permeable packaging exhibited a significantly lower damage accumulation rate compared with inserts sterilized by γ radiation and stored in air or an inert environment. γ irradiation and storage in argon instead of air reduced the frequency of severe damage such as delamination but not the overall damage rate.

Analysis of Migration of Press-Fit Porous-Coated Acetabular Components With Medial Lucencies Using Ein-Bild-Roentegen-Analyse - Corrected Proof

Cameron Sadeghi, Anthony G. Gibson, Michael D. Ries — 2011-12-19

Abstract: A total of 136 patients who underwent total hip arthroplasty (154 hips) with press-fit acetabular components were evaluated for the presence of medial radiographic lucencies. Thirty patients (22.1%) demonstrated radiolucencies greater than 1 mm in zone 2 on initial postoperative films. Ein-Bild-Roentegen-Analyse (EBRA) was used to evaluate component migration over a 5-year follow-up period. Migration, measured by EBRA, was not observed during the first 6 months when the radiolucencies were noted to disappear. After 2 years, the mean total migration was 0.8 mm, and at 5 years, it was 1.6 mm. Our results indicate that disappearance of a medial radiolucency seen on early postoperative radiographs is not associated with component migration, which supports the concept that the medial radiolucency fills in with bone or represents bony remodeling around a stable implant.

Histologic Retrieval Analysis of a Porous Tantalum Metal Implant in an Infected Primary Total Knee Arthroplasty - Corrected Proof

2011-12-19

Abstract: Porous tantalum (Zimmer, Inc, Warsaw, Ind) has the theoretical advantage of improved biologic fixation because of its high porosity, interconnected pore space, and modulus of elasticity. We present a case report documenting the retrieval and bone ingrowth analysis of a porous tantalum tibial component in an infected total knee arthroplasty. Results demonstrated a significantly larger amount of bone ingrowth present in the tibial posts (36.7%) when compared with the bone ingrowth into the tibial baseplate (4.9%) (P < .001). The data suggest that bone ingrowth seen in the plugs as well as baseplate was suggestive of viable bone tissue with healthy bone marrow, osteocytes, and lamella, resulting in a well-fixed tibial implant even at revision surgery for an infected total knee arthroplasty.

Does Osteoporosis Increase Early Subsidence of Cementless Double-Tapered Femoral Stem in Hip Arthroplasty? - Corrected Proof

2011-12-19

Abstract: Among 320 hip arthroplasties performed between January 2007 and March 2008, patients younger than 50 years old and patients older than 70 with a T-score at the proximal femur less than −2.5 made up the control and study group, respectively. There were 40 patients in each group. We measured stem subsidence, both digital and manual methods. Measurements were made from radiographs taken serially from 2 weeks to 1 year after surgery. The amount of mean subsidence for each group was not different, and all stems showed stable fixation in the final radiographs. Our study suggests that even in osteoporotic proximal femurs, press-fit fixation of double-tapered stems for hip arthroplasty can be safe and effective without excessive early subsidence.

Twenty-Year Survival Analysis in Total Knee Arthroplasty by a Single Surgeon - Corrected Proof

2011-12-19

Abstract: Between January 1988 and December 2006, a total of 3014 primary total knee arthroplasties (TKAs) in 2042 patients were performed, and survivorship analysis was performed. Survivorship analysis showed a 10-year survival of 93.8% and a 20-year survival of 70.9%. There was no significant difference in the survival rate according to sex and diagnosis (P = .142 and .443, respectively). The survival rate was higher in the patients older than 60 years (P < .001). The survival rate of Total Condylar IV (TC-IV) was higher than that of Ortholoc (Dow Corning Wright Medical, Arlington, Tenn) (P < .001). Total knee arthroplasty results in satisfactory long-term survival rates. However, the survival rate decreases over time. The risk of requiring revision TKA was related to age and type of implants. Careful consideration is necessary to decide the time for TKA and select type of implants.

The Effectiveness of a Program to Reduce the Rate of Flash Sterilization - Corrected Proof

Julia D. Smart, Stephen M. Belkoff, Simon C. Mears — 2011-12-19

Abstract: Flash sterilization of surgical instruments has been a common practice, but patient safety and quality assurance health care groups have recently recommended minimizing its use. Our goals were to describe the implementation and effectiveness of our institution's program for reducing the flash sterilization rate of instruments used for total hip and knee arthroplasties. We reviewed flash sterilization logs of all hip and knee arthroplasties from the program's implementation in July 2009 through August 2010 (N = 555) and calculated the monthly percentage of cases using flash sterilization. From the first to the last month, the amount of flash sterilization decreased significantly (P < .05): 6 of 34 to 0 of 41, respectively. Our results show that the rate of flash sterilization can be reduced with this strategic program.

Simultaneous Bilateral Total Hip Arthroplasty With Hydroxyapatite-Coated Implants: A 20-Year Follow-Up - Corrected Proof

Ran Schwarzkopf, Patrick Olivieri, William L. Jaffe — 2011-12-19

Abstract: Bilateral hip arthroplasty has been reported to be a safe and effective way to treat bilateral hip arthritis in a selective group of patients. We report a follow-up of 30 patients who underwent simultaneous bilateral total hip arthroplasty with hydroxyapatite implants and were followed for an average of 19.4 years. Patients had an average Harris Hip Score of 90 at the latest follow-up (range, 78-99). The average Western Ontario and McMaster Universities Arthritis Index questionnaire index score was 12 (range, 0-41), with high functional results on the 12-Item Short Form Health Survey (SF-12) and Oxford 12 questioners. Using the Kaplan-Meier survivorship analysis, with revision for any reason as an end point, survivorship was 94% at 12 years, 88% at 15 years, 74% at 18 years, and 61% at 23 years. All revisions were for the acetabular component, and the survivorship for the femoral component was 100% throughout the 23-year period. We conclude that bilateral uncemented total hip arthroplasty can provide satisfactory long-term clinical, radiological, and functional outcomes in patients even with older-generation polyethylene liners and stem designs.

Compartment Syndrome Due to Massive Leg Hematoma After Primary Total Hip Arthroplasty: A Previously Unreported Complication of Fondaparinux - Corrected Proof

Michael G. Hannon, Justin G. Lamont — 2011-12-19

Abstract: Fondaparinux is an accepted form of deep venous thrombosis prophylaxis after hip arthroplasty. Cited advantages of its use include once-daily administration, standard dosage, and superiority as compared with enoxaparin. However, there have been several case reports of serious associated bleeding complications. We describe the case of a 77-year-old woman who developed a massive leg hematoma in the operative extremity nearly 3 weeks after a primary total hip arthroplasty while on fondaparinux. The patient developed a compartment syndrome requiring decompression of the hematoma, fasciotomy, and subsequent additional plastic surgery for split thickness skin grafting.

Letter to the Editor - Corrected Proof

Abbott Kagan — 2011-12-19

The article by Michael Ellman, MD, and Brett Levine, MD, titled “Fracture of the modular femoral neck component in total hip arthroplasty,” published online in the Journal of Arthroplasty presents a patient who sustained a fracture of a modular femoral neck component and underwent 3 surgical procedures to achieve a satisfactory result. The authors refer to 2 of these 3 procedures as “unnecessary.”

Minimum 5-Year Wear Analysis of First-Generation Highly Cross-Linked Polyethylene in Patients 65 Years and Younger - Corrected Proof

2011-12-16

Abstract: The purpose of this study was to analyze wear rates of highly cross-linked polyethylene comparing the Martell and the Roman methods in 112 total hip arthroplasties in patients 65 years and younger, with a mean follow-up of 5.7 years. The mean wear rates in the Martell and Roman methods were 0.014 ± 0.05 mm/y and 0.011 ± 0.04 mm/y when including all values and 0.043 ± 0.028 mm/y and 0.038 ± 0.02 mm/y when negative values were assumed to be zero, respectively. Both Roman and Martell methods showed similar low wear rates with negative values. The Roman method had higher precision and was more user friendly because it required less steps to measure wear, especially when comparing with the manual feature of Martell method.

Third-Generation Ceramic-On-Ceramic Total Hip Arthroplasty in Patients Younger Than 30 Years with Osteonecrosis of Femoral Head - Corrected Proof

Jae-Wook Byun, Taek-Rim Yoon, Kyung-Soon Park, Jong-Keun Seon — 2011-12-12

Abstract: The purpose of this study was to evaluate the functional and radiographic results of patients younger than 30 years who underwent cementless third-generation ceramic-on-ceramic total hip arthroplasty for osteonecrosis of the femoral head. Forty-one patients (56 hips) with a minimum follow-up of 6 years were included. In all cases, third-generation ceramic-on-ceramic articulation was used. Average Harris Hip Scores improved from 52.9 preoperatively to 98.2, and Western Ontario and McMaster Universities Osteoarthritis Index score, from 95.2 to 25.2. Thirty-nine patients returned to their normal occupations. No aseptic loosening or osteolysis was observed. Total hip arthroplasty performed using third-generation ceramic-on-ceramic bearings for osteonecrosis of femoral head was found to provide satisfactory clinical and radiologic results, especially in active, young patients.

Function and Quality of Life in Patients With Recurvatum Deformity After Primary Total Knee Arthroplasty: A Review of Our Joint Registry - Corrected Proof

2011-12-12

Abstract: The aim of this paper is to assess function and quality of life in patients with recurvatum at 2 years after primary total knee arthroplasty. This prospective study involves 2587 total knee arthroplasty from 2004 to 2008 with 2-year follow-up. Patients' demographics, diagnosis, implants, range of motion, laxity, and knee and SF-36 scores were recorded. Recurvatum deformity of 0°, 1° to 5°, 6° to 10°, and more than 10° were classified as grades 0, 1, 2, and 3, respectively. Grade 1 had similar functional scores to grade 0 but significantly better SF1, SF4, SF5, and SF8 when compared with grades 2 and 3. Patients with mediolateral translation of more than 5 mm were more likely to have grades 2 and 3 recurvatum (P = .01), indicating global laxity. Postoperative recurvatum of more than 5° significantly impacts function and quality of life of patients.

Anteversion of the Acetabular Component Aligned With the Transverse Acetabular Ligament in Total Hip Arthroplasty - Corrected Proof

Hideaki Miyoshi, Hiroshi Mikami, Koichi Oba, Rui Amari — 2011-12-12

Abstract: In total hip arthroplasty (THA), accurately positioning the cup is crucial for achieving an adequate postoperative range of motion and stability. For 47 THA cases in which the inferomedial rim of the cup had been positioned parallel to the transverse acetabular ligament, we retrospectively performed the measurements of the radiographic cup anteversion angle relative to the anterior pelvic plane using 3-dimensional reconstruction computed tomography. The mean anteversion angle was 21.2°, with no significant difference detected in mean cup anteversion between the dysplastic hip group (15 hips) and the control group (15 hips). We suggest that the transverse acetabular ligament is a practical anatomical landmark for determining cup anteversion in THA for both dysplastic and nondysplastic hip cases.

The Optimal Skin Incision for Minimally Invasive Total Hip Arthroplasty Performed via the Anterolateral Approach - Corrected Proof

2011-12-12

Abstract: Twelve total hip arthroplasty procedures were performed in fresh cadaveric specimens via the anterolateral approach using straight 9-cm incisions placed in 2 different locations with respect to anatomical landmarks. During each procedure, the forces applied to the wound edges by each of the hip instruments and the pressures and strains generated along the wound edges were measured. Pressures ranging from 40 to 190 kPa were developed between the retractors and the wound edges during acetabular reaming and femoral rasping. The resulting strain along the wound edges averaged 28% during acetabular reaming and 34% during femoral broaching (P < .0001). Maximum strains were recorded at the ends of each incision and averaged 58% and 61%, respectively (P < .0001). These results were independent of the anatomical placement of the skin incision. In total hip arthroplasty, the mechanical trauma associated with the procedure is primarily determined by the surgical approach to the hip and the properties of the subcutaneous tissues, and not the anatomical location of the skin incision itself.

Proximal Femoral Allograft in Revision Hip Surgery With Severe Femoral Bone Loss: A Systematic Review and Meta-Analysis - Corrected Proof

2011-12-09

Abstract: This study provides an objective appraisal of available evidence regarding the outcome of proximal femoral allograft for reconstruction of massive proximal femoral bone loss. The primary outcomes were rates of success, structural failure, and infection. A systematic literature review identified 16 studies with a minimum 2-year follow-up. Estimated pooled effect analysis performed with heterogeneity quantified using I2 and τ2. The total cohort included 498 patients with a mean follow-up of 8.1 years. The pooled success rate was 81%, pooled structural failure rate of 15%, and pooled infection rate of 8%. Significant heterogeneity was observed in structural failure rates (I2 = 47.9, τ2 = 0.29, P < .05). Proximal femoral allografts afford viable reconstruction for massive femoral bone loss when performed by experienced.

Sagittal Flexion of the Femoral Component Affects Flexion Gap and Sizing in Total Knee Arthroplasty - Corrected Proof

Tadashi Tsukeoka, Tae Hyun Lee — 2011-12-09

Abstract: The purpose of this study was to determine how much sagittal rotation of the femoral component affects the flexion gap and femoral component sizing using a computer-simulation technique. The study comprised 25 knees scheduled for total knee arthroplasty (TKA). The femoral component was positioned at −2°, 0°, 2°, 4°, or 6° of flexion to the anterior femoral cortex, and the resected portion of the posterior medial femoral condyle was measured for 3 total knee systems. The amount of the resected bone of the posterior medial condyle decreased approximately 1 mm for every 2° of additional flexion in all TKA systems. Intentional sagittal flexion of the femoral component by several degrees during TKA can be a useful downsizing technique for the femoral component without excessively increasing the flexion gap.

Total Knee Arthroplasty in a Patient With Hemophilic Arthropathy and High-Titer Inhibitors: A Cost Analysis - Corrected Proof

2011-12-09

Abstract: A patient with hemophilia A, who developed factor VIII inhibitors and initially had funding for his total knee arthroplasty declined, is discussed. A total of £1 542 000 (US $2 474 603) was spent on medical treatment for recurrent hemarthroses over a 4-year period, while funding was sought. In comparison, the total cost for his knee arthroplasty was £542 858 (US $871 084) including perioperative recombinant clotting factors. Postoperatively, with 1-year follow-up, no further hemoarthroses have occurred; his analgesic requirement is significantly reduced; he has a much improved level of function; and treatment costs are significantly reduced, leading to a substantial overall saving. Our findings suggest that surgical treatment is beneficial and cost-effective for patients with hemophilia with inhibitors. Hospitals should not deny operative treatment based on cost alone.