The Association of Sacro-Femoro-Pubic Angle and Postoperative Dislocation Following Total Hip Arthroplasty.

BACKGROUND: Spino-pelvic orientation may affect dislocation risk following total hip arthroplasty (THA). It can be measured on lateral lumbo-pelvic radiographs. The sacro-femoro-pubic (SFP) angle, measured on an antero-posterior (AP) pelvis radiograph, is a reliable proxy for pelvic tilt, a measurement of spino-pelvic orientation measured on a lateral lumbo-pelvic radiograph. The purpose of this study was to investigate the relationship between SFP angle and dislocation following THA. METHODS: An Institutional Review Board-approved retrospective case-control study was conducted at a single academic center. We matched 71 dislocators (cases) to 71 nondislocators (controls) following THA performed by 1 of 10 surgeons between September 2001 and December 2010. Two authors (readers) independently calculated SFP angle from single preoperative AP pelvis radiographs. Readers were blinded to cases and controls. Conditional logistic regressions were used to identify factors differentiating cases and controls. RESULTS: The data did not show a clinically relevant or statistically significant difference in SFP angles after adjusting for gender, American Society of Anesthesiologists classification, prosthetic head size, age at time of THA, measurement laterality, and surgeon. CONCLUSION: We did not find an association between preoperative SFP angle and dislocation following THA in our cohort. Based on our data, SFP angle as measured on a single AP pelvis radiograph should not be used to assess dislocation risk prior to THA.

Short-Term Surgical Missions: Role of Pharmacist Volunteers.

Health care professionals often participate in short-term surgical missions in underserved areas of the world. Surgical missions often rely on the use of medications to provide health care to these underserved areas in patients with multiple comorbid conditions. The direct role a pharmacist may have in surgical missions is not well described in the literature; however, numerous opportunities exist for pharmacist involvement to improve patient care and operational processes throughout medication planning and delivery of surgical missions. Pharmacists have specialized knowledge in medication acquisition, preparation, and distribution that result in a unique position to contribute positively to the mission's clinical and operational dynamics. Pharmacists may assist in various activities such as medication ordering, accrual, purchasing and preparing during the surgical mission. Pharmacists may also provide clinical support and offer alternative medications in the setting of drug intolerance or allergies. In 2008, Operation Walk Boston, a short-term surgical mission was established to provide hip and knee joint replacements to patients in the Dominican Republic. Pharmacists and pharmacy residents play a crucial role as members of this surgical mission. Based on our experience, this article aims to describe the evolving role of pharmacists as a member of a surgical mission.

Factors associated with use of antibiotic prophylaxis following dental procedures in total joint replacement recipients.

Background: Total joint replacement recipients (TJR) are at risk for prosthetic joint infection (PJI), particularly those with comorbidities such as diabetes mellitus (DM) and rheumatoid arthritis (RA). Methods: We mailed surveys to 1078 subjects undergoing primary TJR between 2011 and 2016 â€‹at an academic center. The survey asked about medical, dental, and orthopedic history and use of antibiotics prior to dental appointments. We generated adjusted relative risks (aRR) for using antibiotic prophylaxis less than always using Poisson regression, adjusting for demographic, clinical, and behavioral factors. Results: We received surveys from 639 subjects; 597 were eligible and formed the analytical sample. 66 â€‹% reported always using antibiotic prophylaxis. DM and RA were not associated with prophylaxis use. Factors associated with less frequent use included: BMI ≥30 (aRR â€‹= â€‹1.27, 95 â€‹% CI [1.01, 1.60]), dental cleanings <2 times/year (aRR â€‹= â€‹1.95, 95 â€‹% CI [1.56, 2.43]), and expressing little concern (compared to neutral) about getting PJI (aRR â€‹= â€‹1.23, 95 â€‹% CI [0.97, 1.55]), though this association was not statistically significant. Greater antibiotic use was reported in subjects who had ≥3 TJRs, (aRR â€‹= â€‹0.48, 95 â€‹% CI [0.29, 0.80]), underwent more invasive dental procedures (aRR â€‹= â€‹0.74, 95 â€‹% CI [0.59, 0.93]), and were concerned (vs. neutral) about PJI (aRR â€‹= â€‹0.53, 95 â€‹%CI [0.33, 0.84]). Conclusions: Two-thirds of TJR recipients in an academic center reported always using antibiotic prophylaxis prior to dental visits. Usage rates varied by demographics, BMI, number of TJRs, type of dental procedure, and behavioral factors -- but not by comorbidities associated with higher PJI risk.

Notch signalling drives synovial fibroblast identity and arthritis pathology.

The synovium is a mesenchymal tissue composed mainly of fibroblasts, with a lining and sublining that surround the joints. In rheumatoid arthritis the synovial tissue undergoes marked hyperplasia, becomes inflamed and invasive, and destroys the joint1,2. It has recently been shown that a subset of fibroblasts in the sublining undergoes a major expansion in rheumatoid arthritis that is linked to disease activity3-5; however, the molecular mechanism by which these fibroblasts differentiate and expand is unknown. Here we identify a critical role for NOTCH3 signalling in the differentiation of perivascular and sublining fibroblasts that express CD90 (encoded by THY1). Using single-cell RNA sequencing and synovial tissue organoids, we found that NOTCH3 signalling drives both transcriptional and spatial gradients-emanating from vascular endothelial cells outwards-in fibroblasts. In active rheumatoid arthritis, NOTCH3 and Notch target genes are markedly upregulated in synovial fibroblasts. In mice, the genetic deletion of Notch3 or the blockade of NOTCH3 signalling attenuates inflammation and prevents joint damage in inflammatory arthritis. Our results indicate that synovial fibroblasts exhibit a positional identity that is regulated by endothelium-derived Notch signalling, and that this stromal crosstalk pathway underlies inflammation and pathology in inflammatory arthritis.

Cost-effectiveness of dental antibiotic prophylaxis in total knee arthroplasty recipients with type II diabetes mellitus.

Objective: Type II diabetes mellitus (T2DM) is prevalent in knee osteoarthritis (OA) patients undergoing total knee arthroplasty (TKA) and increases risk for prosthetic joint infection (PJI). We examined the cost-effectiveness of antibiotic prophylaxis (AP) before dental procedures to reduce PJI in TKA recipients with T2DM. Design: We used the Osteoarthritis Policy Model, a validated computer simulation of knee OA, to compare two strategies among TKA recipients with T2DM (mean age 68 years, mean BMI 35.4 kg/m2): 1) AP before dental procedures and 2) no AP. Outcomes included quality-adjusted life expectancy (QALE) and lifetime medical costs. We used published efficacy of AP. We report incremental cost-effectiveness ratios (ICERs) and considered strategies with ICERs below well-accepted willingness-to-pay (WTP) thresholds cost-effective. We conducted sensitivity analyses to examine the robustness of findings to uncertainty in model input parameters. We used a lifetime horizon and healthcare sector perspective. Results: We found that AP added 1.0 quality-adjusted life-year (QALY) and $66,000 for every 1000 TKA recipients with T2DM, resulting in an ICER of $66,000/QALY. In sensitivity analyses, reduction of the probability of PJI, T2DM-associated risk of infection, or attribution of infections to dental procedures by 50% resulted in ICERs exceeding $100,000/QALY. Probabilistic sensitivity analyses showed that AP was cost-effective in 32% and 58% of scenarios at WTP of $50,000/QALY and $100,000/QALY, respectively. Conclusions: AP prior to dental procedures is cost-effective for TKA recipients with T2DM. However, the cost-effectiveness of AP depends on the risk of PJI and efficacy of AP in this population.

A Conceptual Model for the Evaluation of Surgical Missions.

BACKGROUND: Medical missions to low and middle-income countries are increasingly frequent, with an estimated 6,000 trips sponsored by U.S. organizations accounting for approximately 200,000 surgical cases and $250 million in costs annually. However, these missions have received little critical evaluation. This paper describes the research program Operation Walk (Op-Walk) Boston, and proposes an evaluation model for similar surgical missions. METHODS: We propose an evaluation model, borrowing from the work of Donabedian and enriched by evidence from our research program. The model calls for evaluation of the salient contextual factors (culture and beliefs), system management (structure, process, and outcomes), and sustainability of the program's interventions. We used these domains to present findings from the quantitative and qualitative research work of Op-Walk Boston. RESULTS: Op-Walk's qualitative research findings demonstrated that cultural factors are important determinants of patients' perceptions of arthritis etiology, physical activity patterns, and treatment preferences. Quantitative assessments documented that Dominican patients had worse lower-extremity functional status (mean Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] function score of 33.6) and pain preoperatively than patients undergoing total hip or knee replacement in the U.S. (WOMAC function score of 43.3 to 54), yet they achieved excellent outcomes (50-point improvement), comparable to those of their U.S. counterparts. Assessments of the quality and sustainability of the Op-Walk program showed that the quality of care provided by Op-Walk Boston meets Blue Cross Blue Shield Centers of Excellence (Blue Distinction) criteria, and that sustainable changes were transferred to the host hospital. CONCLUSIONS: Our proposed model offers a method for formal assessment of medical missions that addresses the call for evidence of their merit. We suggest that surgical missions adopt quantitative and qualitative strategies to document their impact, identify areas of improvement, and justify program continuation, growth, and support.

Predictors of Patient-Reported Outcomes of Total Joint Arthroplasty in a Developing Country.

BACKGROUND: In response to the growing burden of joint disease, developing countries are starting to create their own total joint arthroplasty (TJA) programs. To date, there has been limited research on predictors of TJA outcomes in a developing country. This investigation uses patient-reported outcome measures collected by a medical mission to assess predictors of TJA outcomes in the Dominican Republic. METHODS: Baseline and postoperative information from 156 of the mission's recipients of hip and knee TJA was used. Demographics were abstracted from clinical notes, and self-reported pain and functional status were assessed using Western Ontario and McMaster University Osteoarthritis Index and Short-Form 36 measures. Bivariate analysis identified variables to include in multivariable regression models of factors associated with function and pain outcomes and improvement in these domains 1 or 2 years postoperatively. RESULTS: The cohort had a mean age of 61.3 years, 82% were female, 79% had total knee arthroplasty, and 42% of the procedures were bilateral. In multivariate analyses, at P < .05, male sex, better preoperative function, and use of bilateral procedure were associated with better functional outcome. Male sex and worse preoperative pain were associated with better pain outcome. Worse preoperative pain and function, as well as bilateral surgery were associated with greater improvement in function. Additionally, a greater number of bothersome joints was associated with greater pain reduction. CONCLUSION: Our findings of better follow-up pain scores among patients with worse pain preoperatively and better functional improvement among those undergoing bilateral replacements contrast with study results from developed countries. The explanations for these observations merit further study.

The Evolution of Implant Design Decreases the Incidence of Lateral Release in Primary Total Knee Arthroplasty.

BACKGROUND: Appropriate balancing of the patellofemoral joint (PFJ) using a lateral release can help to prevent patellar instability in total knee arthroplasty (TKA). Contemporary total knee implant designs are characterized by enhanced trochlear geometry more similar to native knee anatomy to minimize instability and reduce utilization of a lateral release. METHODS: We retrospectively reviewed consecutive TKA cases from a single senior surgeon's practice with 3 successive total knee designs: the Press-Fit Condylar (PFC), the Sigma, and the ATTUNE (DePuy, Warsaw, IN). We evaluated the use of lateral release with each implant type to determine if design changes have improved patellar stability, reducing the need for lateral release. We used multivariate analysis to determine the association between implant type and lateral release, adjusting for age, sex, preoperative alignment, and bearing type. RESULTS: We evaluated 1991 records of primary TKAs performed from 1980-2015. As compared with the ATTUNE, the adjusted odds of lateral release were greater for patients receiving PFC implants (Odds ratio [OR] 6.35, 95% confidence interval [CI] 3.85,10.49) and Sigma implants (OR 2.02, 95% CI 1.26, 3.23). In addition, fixed bearing implants were associated with greater adjusted odds of lateral release (OR 1.80, 95% CI 1.24, 2.62). CONCLUSION: We found that older knee implants were associated with higher use of lateral release, with successive designs the need for lateral release to balance the PFJ decreased. Continued design improvements to match the native knee anatomy may further improve the stability of the PFJ in future designs.

Postoperative Pain Management Among Dominican and American Health-Care Providers: A Qualitative Analysis.

BACKGROUND: U.S. practitioners have prescribed opioid analgesics increasingly in recent years, contributing to what has been declared an opioid epidemic by the U.S. Centers for Disease Control and Prevention (CDC). Opioids are used frequently in the preoperative and postoperative periods for patients undergoing total joint replacement in developed countries, but cross-cultural comparisons of this practice are limited. An international medical mission such as Operation Walk Boston, which provides total joint replacement to financially vulnerable patients in the Dominican Republic, offers a unique opportunity to compare postoperative pain management approaches in a developed nation and a developing nation. METHODS: We interviewed American and Dominican surgeons and nurses (n = 22) during Operation Walk Boston 2015. We used a moderator's guide with open-ended questions to inquire about postoperative pain management and factors influencing prescribing practices. Interviews were recorded and transcripts were analyzed using content analysis. RESULTS: Providers highlighted differences in the patient-provider relationship, pain medication prescribing variability, and access to medications. Dominican surgeons emphasized adherence to standardized pain protocols and employed a paternalistic model of care, and American surgeons reported prescribing variability and described shared decision-making with patients. Dominican providers described limited availability of potent opioid preparations in the Dominican Republic, in contrast to American providers, who discussed opioid accessibility in the United States. CONCLUSIONS: Our findings suggest that cross-cultural comparisons provide insight into how opioid prescribing practices, approaches to the patient-provider relationship, and medication access inform distinct pain management strategies in American and Dominican surgical settings. Integrating lessons from cross-cultural pain management studies may yield more effective pain management strategies for surgical procedures performed in the United States and abroad.

J-integral fracture toughness, Tearing modulus and tensile properties of Vitamin E stabilized radiation crosslinked UHMWPE.

Radiation crosslinking of ultra-high molecular weight polyethylene (UHMWPE) increases its wear resistance in total joint replacement prostheses. Unfortunately, it is accompanied by a dose-dependent decrease in several mechanical properties. In this study, the tensile properties and fracture behavior of radiation crosslinked, Vitamin E stabilized UHMWPE was studied as a function of radiation dose. The Rice and Sorensen model, applicable to elastic-plastic materials, was utilized to obtain the initial crack driving force, J1c, steady state J-integral fracture toughness, Jss and the Tearing modulus. Tensile tests showed the dependence of tensile properties on radiation dose. Jss of non-crosslinked UHMWPE was higher than for crosslinked UHMWPE׳s but there was no dose dependent change in Jss whereas there was almost no change in J1c over the entire dose range. Finally, a monotonic decrease in Tearing modulus was observed with radiation dose.

Mortality Risk Assessment of Total Knee Arthroplasty and Related Surgery After Percutaneous Coronary Intervention.

BACKGROUND: The optimal antiplatelet therapy (APT) treatment strategy after Coronary Artery Stenting (CAS) in non-cardiac surgery, such as total knee arthroplasty (TKA) or urgent TKA-related surgery remains unknown. METHODS: We built a decision tree model to examine the mortality outcomes of two alternative strategies for APT after CAS use in the perioperative period namely, continuous use and discontinuation. RESULTS: If surgery was performed in the first month after CAS placement, discontinuing APT led to an estimated 30-day post TKA mortality of 10.5%, compared to 1.0% in a strategy with continuous APT use. Mortality with both strategies decreased with longer intervals. CONCLUSION: Our model demonstrated that APT discontinuation in patients undergoing TKA or urgent TKA related surgery after CAS placement might lead to greater 30-day mortality up to one year.

Influence of osteoarthritis grade on molecular signature of human cartilage.

Articular chondrocytes maintain cartilage matrix turnover and have the capacity for anabolic and catabolic activities that can be influenced by injury and disease. This study tested the hypothesis that catabolic genes are upregulated with regional osteoarthritis (OA) disease severity within a joint. With IRB approval, specimens of knee cartilage obtained as discarded tissues from subjects undergoing arthroplasty were partitioned for each subject by OA disease severity and evaluated for gene expression by RT-PCR. There was regional OA grade-associated upregulation of expected inflammatory mediators TNF-α, TNF receptors, IFN-γ, and interleukins as well as genes encoding proteolytic enzymes, including Adamts-5 and MMPs. Osteoclast-related genes, cathepsin K, tartrate-resistant acid phosphatase (TRAP), RANKL, RANK, M-CSF, and c-fms, but not osteoprotegerin, were induced in advanced grades. In vitro treatment of normal human chondrocytes with interleukin-1ß upregulated similar genes; this provides evidence that chondrocytes per se can be the source of osteoclast-related factors. Immunohistochemical staining showed that RANK- and RANKL-positive cells were abundant in advanced grades, especially in chondrocyte clusters. This suggests a possible autocrine mechanism by which an osteoclast phenotype is induced in articular chondrocytes. In sum, these studies identified gene expression signatures in human OA cartilage based upon regional disease severity within a joint. There was an effect of OA Grade on expression of osteoclastic lytic enzymes and regulatory factors in human articular chondrocytes. Induction of an osteoclast-like phenotype in chondrocytes may be part of OA progression and suggests specific therapeutic approaches.

Effect of smoking and soft tissue release on risk of revision after total knee arthroplasty: a case- control study.

BACKGROUND: Increasing utilization of primary total knee arthroplasty (TKA) is projected to expand demand for revision TKA. Revision TKAs are procedurally complex and incur high costs on our financially constrained healthcare system. The purpose of this study was to use a case-control design to identify factors predisposing to revision TKA, particularly demographic, clinical and perioperative technical factors. METHODS: We conducted a case control study to investigate patient, surgical and perioperative factors associated with greater risk of revision TKA. We included patients who received TKA at a tertiary center between 1996 and 2009. Cases (patients that had primary and revision TKA) were matched to controls (patients with primary TKA that was not revised) in a 1:2 ratio and risk of revision examined using conditional logistic regression. RESULTS: We identified 146 cases and 290 controls. Patient factors independently associated with revision included male sex (OR 1.73; 95% CI 1.06-2.81) and smoking (OR 2.87; 1.33-6.19). Older age was associated with decreased risk (OR 0.83 per 5-year increment; 95% CI 0.75-0.92). Lateral release was the only technical factor associated with revision (OR 1.92; 1.07-3.43). CONCLUSIONS: In this case control study younger patient age, male gender, soft tissue release and active smoking status were associated with increased revision risk. Although we do not know whether the risk of smoking arises from short- or long-term exposure, smoking cessation prior to TKA should be considered as an intervention for decreasing revision risk.

Sustainability assessment of a short-term international medical mission.

BACKGROUND: Few studies have analyzed the tangible impact of global, philanthropic medical missions. We used qualitative methods to analyze the work of one such mission, Operation Walk Boston, which has made yearly trips to a Dominican Republic hospital since 2008. METHODS: We interviewed twenty-one American and Dominican participants of the Operation Walk Boston team to investigate how the program led to changes at the host Dominican hospital and how the experience caused both mission protocols and U.S. practices to change. Transcripts were analyzed with the use of content analysis. RESULTS: Participants noted that Operation Walk Boston's technical knowledge transfer and managerial examples led to sustainable changes at the Dominican hospital. Additionally, participants observed an evolution in nursing culture, as the program inspired greater independence in decision-making. Participants also identified barriers such as language and organizational hierarchy that may limit bidirectional knowledge transfer. U.S. participants noted that their practices at home changed as a result of better appreciation for different providers' roles and for managing cost in a resource-constrained environment. CONCLUSIONS: Operation Walk Boston catalyzed sustainable changes in the Dominican hospital. Cultural norms and organizational structure are important determinants of program sustainability.

The cost-effectiveness of surgical treatment of medial unicompartmental knee osteoarthritis in younger patients: a computer model-based evaluation.

BACKGROUND: Surgical options for the management of medial compartment osteoarthritis of the varus knee include high tibial osteotomy, unicompartmental knee arthroplasty, and total knee arthroplasty. We sought to determine the cost-effectiveness of high tibial osteotomy and unicompartmental knee arthroplasty as alternatives to total knee arthroplasty for patients fifty to sixty years of age. METHODS: We built a probabilistic state-transition computer model with health states defined by pain, postoperative complications, and subsequent surgical procedures. We estimated transition probabilities from published literature. Costs were determined from Medicare reimbursement schedules. Health outcomes were measured in quality-adjusted life-years (QALYs). We conducted analyses over patients' lifetimes from the societal perspective, with health and cost outcomes discounted by 3% annually. We used probabilistic sensitivity analyses to account for uncertainty in data inputs. RESULTS: The estimated discounted QALYs were 14.62, 14.63, and 14.64 for high tibial osteotomy, unicompartmental knee arthroplasty, and total knee arthroplasty, respectively. Discounted total direct medical costs were $20,436 for high tibial osteotomy, $24,637 for unicompartmental knee arthroplasty, and $24,761 for total knee arthroplasty (in 2012 U.S. dollars). The incremental cost-effectiveness ratio (ICER) was $231,900 per QALY for total knee arthroplasty and $420,100 per QALY for unicompartmental knee arthroplasty. Probabilistic sensitivity analyses showed that, at a willingness-to-pay (WTP) threshold of $50,000 per QALY, high tibial osteotomy was cost-effective 57% of the time; total knee arthroplasty, 24%; and unicompartmental knee arthroplasty, 19%. At a WTP threshold of $100,000 per QALY, high tibial osteotomy was cost-effective 43% of time; total knee arthroplasty, 31%; and unicompartmental knee arthroplasty, 26%. CONCLUSIONS: In fifty to sixty-year-old patients with medial unicompartmental knee osteoarthritis, high tibial osteotomy is an attractive option compared with unicompartmental knee arthroplasty and total knee arthroplasty. This finding supports greater utilization of high tibial osteotomy for these patients. The cost-effectiveness of high tibial osteotomy and of unicompartmental knee arthroplasty depend on rates of conversion to total knee arthroplasty and the clinical outcomes of the conversions.

Can therapy dogs improve pain and satisfaction after total joint arthroplasty? A randomized controlled trial.

BACKGROUND: The use of animals to augment traditional medical therapies was reported as early as the 9th century but to our knowledge has not been studied in an orthopaedic patient population. The purpose of this study was to evaluate the role of animal-assisted therapy using therapy dogs in the postoperative recovery of patients after THA and TKA. QUESTIONS/PURPOSES: We asked: (1) Do therapy dogs have an effect on patients' perception of pain after total joint arthroplasty as measured by the VAS? (3) Do therapy dogs have an effect on patients' satisfaction with their hospital stay after total joint arthroplasty as measured by the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS)? METHODS: A randomized controlled trial of 72 patients undergoing primary unilateral THA or TKA was conducted. Patients were randomized to a 15-minute visitation with a therapy dog before physical therapy or standard postoperative physical therapy regimens. Both groups had similar demographic characteristics. Reduction in pain was assessed using the VAS after each physical therapy session, beginning on postoperative Day 1 and continuing for three consecutive sessions. To ascertain patient satisfaction, the proportion of patients selecting top-category ratings in each subsection of the HCAHPS was compared. RESULTS: Patients in the treatment group had lower VAS scores after each physical therapy session with a final VAS score difference of 2.4 units (animal-assisted therapy VAS, 1.7; SD, 0.97 [95% CI, 1.4-2.0] versus control VAS, 4.1; SD, 0.97 [95% CI, 3.8-4.4], p<0.001) after the third physical therapy session. Patients in the treatment group had a higher proportion of top-box HCAHPS scores in the following fields: nursing communication (33 of 36, 92% [95% CI, 78%-98%] versus 69%, 25 of 36 [95% CI, 52%-84%], p=0.035; risk ratio, 1.3 [95% CI of risk ratio, 1.0-1.7]; risk difference, 23% [95% CI of risk difference, 5%-40%]), pain management (34 of 36, 94% [95% CI, 81%-99%], versus 26 of 36, 72% [95% CI, 55%-86%], p=0.024; risk ratio, 1.3 [95% CI of risk ratio, 1.1-1.6]; risk difference, 18% [95% CI of risk difference, 5%-39%]). The overall hospital rating also was greater in the treatment group (0-10 scale) (9.6; SD, 0.7 [95% CI, 9.3-9.8] versus 8.6, SD, 0.9 [95% CI, 8.3-8.9], p<0.001). CONCLUSIONS: The use of therapy dogs has a positive effect on patients' pain level and satisfaction with hospital stay after total joint replacement. Surgeons are encouraged to inquire about the status of volunteer-based animal-assisted therapy programs in their hospital as this may provide a means to improve the immediate postoperative recovery for a select group of patients having total joint arthroplasty. LEVEL OF EVIDENCE: Level II, randomized controlled study. See Instructions for Authors for a complete description of levels of evidence.

Cruciate-retaining TKA is an option in patients with prior patellectomy.

BACKGROUND: The recommendation for using posterior-stabilized (PS) implants in patellectomy patients undergoing total knee arthroplasty (TKA) is based on older case series with heterogeneous patient populations. The use of cruciate-retaining implants in these patients has not been evaluated with more contemporary implant designs. QUESTIONS/PURPOSES: The purpose of this study was to evaluate the survivorship and functional outcomes (Knee Society score, presence of an extensor lag, and range of motion) of cruciate-retaining (CR) TKA in patients with prior patellectomy. METHODS: Between 1986 and 2012, we performed 27 CR TKAs in 25 patients after patellectomy. Of those, 23 CR TKAs in 21 patients were available for followup at a minimum of 2 years (mean, 11.2 years; range, 2.3-25.1 years). In this retrospective study, we queried a prospectively maintained database to assess functional outcomes and survivorship. RESULTS: Aseptic loosening-free survival was 100% at 5 and 10 years, and survival with revision for any reason as the outcome was 96% at 5 years (95% confidence interval [CI], 87.7%-100%) and 84% at 10 years (95% CI, 69.5%-100%). One patient was revised for aseptic loosening at 10.2 years postoperatively. Mean Knee Society scores improved from 36±13 preoperatively to 92±9.6 at followup. Extensor lag was present in seven patients preoperatively and only three at followup. Average knee flexion at followup was 112°±12.5°. CONCLUSIONS: In this study we found good long-term survivorship and functional outcomes with a CR implant design in patients following patellectomy. Earlier studies have favored PS over CR implants for patients with patellectomies. We believe this series suggests that CR TKA is indeed an option in patients with patellectomy. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Participation in physical activity in patients 1-4 years post total joint replacement in the Dominican Republic.

BACKGROUND: To address both the growing burden of joint disease and the gaps in medical access in developing nations, medical relief organizations have begun to launch programs to perform total joint replacement (TJR) on resident populations in developing countries. One outcome of TJR of particular interest is physical activity (PA) since it is strongly linked to general health. This study evaluates the amount of postoperative participation in PA in low-income patients who received total joint replacement in the Dominican Republic and identifies preoperative predictors of postoperative PA level. METHODS: We used the Yale Physical Activity Survey (YPAS) to assess participation in postoperative PA 1-4 years following total knee or hip replacement. We compared the amount of aerobic PA reported by postoperative TJR patients with the levels of PA recommended by the CDC and WHO. We also analyzed preoperative determinants of postoperative participation in aerobic PA in bivariate and multivariate analyses. RESULTS: 64 patients out of 170 eligible subjects (52/128 TKR and 14/42 THR) who received TJR between 2009-2012 returned for an annual follow-up visit in 2013, with a mean treatment-to-follow-up time of 2.1 years. 43.3% of respondents met CDC/WHO criteria for sufficient participation in aerobic PA. Multivariate analyses including data from 56 individuals identified that patients who were both younger than 65 and at least two years postoperative had an adjusted mean activity dimensions summary index (ADSI) 22.9 points higher than patients who were 65 or older and one year postoperative. Patients who lived with friends or family had adjusted mean ADSI 17.2 points higher than patients living alone. Patients who had the most optimistic preoperative expectations of outcome had adjusted mean ADSI scores that were 19.8 points higher than those who were less optimistic. CONCLUSION: The TJR patients in the Dominican cohort participate in less PA than recommended by the CDC/WHO. Additionally, several associations were identified that potentially affect PA in this population; specifically, participants who are older than 65, recently postoperative, less optimistic about postoperative outcomes and who live alone participate in less PA.

Factors Associated With the Failure of Surgical Treatment for Femoroacetabular Impingement: Review of the Literature.

BACKGROUND: With the recent increased recognition of femoroacetabular impingement (FAI) as a cause of hip pain and early osteoarthritis, surgical treatment has proliferated. There is a growing body of literature on outcomes of surgical intervention for FAI, but factors associated with inferior surgical outcomes have not been reviewed systematically. PURPOSE: To review the available literature and identify factors associated with the failure of open or arthroscopic surgery for FAI. STUDY DESIGN: Systematic review. METHODS: Using the PubMed database, we searched for relevant English-language articles published from January 1966 through August 2012. Inclusion criteria were a primary focus on the surgical treatment of FAI, measurement of functional or pain outcomes, identification of treatment failures, and statistical analysis of factors leading to failure. Exclusion criteria were review articles, technique-only articles, and studies of nonoperative management. Two definitions of failure were considered: (1) a lack of statistically significant improvement in validated measures of pain, function, or satisfaction postoperatively; and (2) revision surgery or conversion to hip arthroplasty because of persistent symptoms. The consistency of association between preoperative variables and clinical outcomes was reported across all studies. RESULTS: Thirteen studies were included. Three were retrospective; there were no randomized controlled trials. Many studies had important methodological limitations. Preoperative cartilage damage or osteoarthritis had the strongest and most consistent relationship with conversion to hip arthroplasty and with a lack of improvement in pain or function. Greater age at the index operation, worse preoperative modified Harris Hip Score, and longer duration of symptoms preoperatively (>1.5 years) were associated with conversion to hip arthroplasty. CONCLUSION: Older age, presence of arthritic changes, longer duration of symptoms, and worse preoperative pain and functional scores are associated with poor outcomes of surgery for FAI. Incorporation of these data into discussions with patients may facilitate informed, shared decision making about the surgical treatment of FAI.

Enhancing the quality of international orthopedic medical mission trips using the blue distinction criteria for knee and hip replacement centers.

BACKGROUND: Several organizations seek to address the growing burden of arthritis in developing countries by providing total joint replacements (TJR) to patients with advanced arthritis who otherwise would not have access to these procedures. Because these mission trips operate in resource poor environments, some of the features typically associated with high quality care may be difficult to implement. In the U.S., many hospitals that perform TJRs use the Blue Cross/Shield's Blue Distinction criteria as benchmarks of high quality care. Although these criteria were designed for use in the U.S., we applied them to Operation Walk (Op-Walk) Boston's medical mission trip to the Dominican Republic. Evaluating the program using these criteria illustrated that the program provides high quality care and, more importantly, helped the program to find areas of improvement. METHODS: We used the Blue Distinction criteria to determine if Op-Walk Boston achieves Blue Distinction. Each criterion was grouped according to the four categories included in the Blue Distinction criteria--"general and administrative", "structure", "process", or "outcomes and volume". Full points were given for criteria that the program replicates entirely and zero points were given for criteria that are not replicated entirely. Of the non-replicated criteria, Op-Walk Boston's clinical and administrative teams were asked if they compensate for failure to meet the criterion, and they were also asked to identify barriers that prevent them from meeting the criterion. RESULTS: Out of 100 possible points, the program received 71, exceeding the 60-point threshold needed to qualify as a Blue Distinction center. The program met five out of eight "required" criteria and 11 out of 19 "informational" criteria. It scored 14/27 in the "general" category, 30/36 in the "structure" category, 17/20 in the "process" category, and 10/17 in the "outcomes and volume" category. CONCLUSION: Op-Walk Boston qualified for Blue Distinction. Our analysis highlights areas of programmatic improvement and identifies targets for future quality improvement initiatives. Additionally, we note that many criteria can only be met by hospitals operating in the U.S. Future work should therefore focus on creating criteria that are applicable to TJR mission trips in the context of developing countries.