A protein complex network of Drosophila melanogaster.

Determining the composition of protein complexes is an essential step toward understanding the cell as an integrated system. Using coaffinity purification coupled to mass spectrometry analysis, we examined protein associations involving nearly 5,000 individual, FLAG-HA epitope-tagged Drosophila proteins. Stringent analysis of these data, based on a statistical framework designed to define individual protein-protein interactions, led to the generation of a Drosophila protein interaction map (DPiM) encompassing 556 protein complexes. The high quality of the DPiM and its usefulness as a paradigm for metazoan proteomes are apparent from the recovery of many known complexes, significant enrichment for shared functional attributes, and validation in human cells. The DPiM defines potential novel members for several important protein complexes and assigns functional links to 586 protein-coding genes lacking previous experimental annotation. The DPiM represents, to our knowledge, the largest metazoan protein complex map and provides a valuable resource for analysis of protein complex evolution.

Periprosthetic joint infection.

Periprosthetic joint infections are a devastating complication after arthroplasty and are associated with substantial patient morbidity. More than 25% of revisions are attributed to these infections, which are expected to increase. The increased prevalence of obesity, diabetes, and other comorbidities are some of the reasons for this increase. Recognition of the challenge of surgical site infections in general, and periprosthetic joint infections particularly, has prompted implementation of enhanced prevention measures preoperatively (glycaemic control, skin decontamination, decolonisation, etc), intraoperatively (ultraclean operative environment, blood conservation, etc), and postoperatively (refined anticoagulation, improved wound dressings, etc). Additionally, indications for surgical management have been refined. In this Review, we assess risk factors, preventive measures, diagnoses, clinical features, and treatment options for prosthetic joint infection. An international consensus meeting about such infections identified the best practices and further research needs. Orthopaedics could benefit from enhanced preventive, diagnostic, and treatment methods.

Venous Thromboembolic Disease in Revision vs Primary Total Knee Arthroplasty.

BACKGROUND: Venous thromboembolic disease (VTED) is a serious complication of primary and revision total knee arthroplasty (TKA). However, the incidence and risk of VTED for revision compared with primary TKA cases have not been well-described. METHODS: We identified 225,584 TKAs (208,954 primaries, 16,630 revisions) in the 2003-2012 Statewide Planning and Research Cooperative System database. Odds ratios (ORs) expressed the risk of VTED for revision vs primary TKA, and models were adjusted for age, gender, race, and Charlson comorbidity scores. Outcome analyses were further stratified into deep venous thromboses (DVTs) and pulmonary emboli (PEs). RESULTS: The incidence of VTED within 30 days was 2.24% for primary and 1.84% for revision. In multivariable-adjusted regression, the OR of VTED within 30 days for revision compared with primary was 0.81 (95% confidence interval = 0.72-0.91; P < .001). The incidence of VTED within 90 days was 2.42% for primary and 2.13% for revision (P = .022), with a multivariable-adjusted OR of 0.87 (95% confidence interval = 0.78-0.97; P = .010) for revision compared with primary. The association was stronger for PE (OR = 0.63; P < .001) than DVT (OR = 0.87; P = .035) at 30 days, and significant for PE (OR = 0.69; P < .001), but not DVT (OR = 0.94; P = .284) at 90 days. CONCLUSION: In a large statewide database, the risk of VTED was lower for revision TKA compared with primary TKA. The reasons for this observation are not known, but might be related to aggressive prophylactic management of patients undergoing revision procedures. Future studies should attempt to clarify differences in patient selection and management for primary vs revision procedures.

Does Preadmission Cutaneous Chlorhexidine Preparation Reduce Surgical Site Infections After Total Knee Arthroplasty?

BACKGROUND: Many preventive methodologies seek to reduce the risk of surgical site infections after total knee arthroplasty (TKA), including the use of preoperative chlorhexidine baths and cloths. Although we have demonstrated in previous studies that this may be an efficacious method for infection prevention, our study was underpowered and we therefore set out to evaluate this with a larger sample size. QUESTIONS/PURPOSES: (1) Does a preadmission chlorhexidine cloth skin preparation protocol decrease the risk of surgical site infection in patients undergoing TKA? (2) When stratified using the National Healthcare Safety Network (NHSN) risk categories, which categories are associated with risk reduction from the preadmission chlorhexidine preparation protocol? METHODS: In our study, all patients (3717 total) who had undergone primary or revision TKA at a single institution between January 1, 2007, and December 31, 2013, were identified, of whom 991 patients used the chlorhexidine cloths before surgery and 2726 patients did not. All patients were provided cloths with instructions before surgery; however, as a result of a lack of compliance, we were able to substratify patients into treatment and control cohorts. Additionally, we substratified patients by NHSN risk category to determine differences in infection between the two cohorts (cloth versus no cloth). Patient medical records and an infection-tracking database were reviewed to determine the development of periprosthetic infection (patients who had superficial infections were excluded from our study) in both groups after 1 year surveillance. We then calculated relative risk reductions with use of chlorhexidine gluconate and stratified results based on NHSN risk category. RESULTS: Use of a preoperative chlorhexidine cloth skin preparation protocol is associated with reduced relative risk of periprosthetic infection after TKA (infections with protocol: three of 991 [0.3%]; infections in control: 52 of 2726 [1.9%]; relative risk [RR]: 6.3 [95% confidence interval [CI], 1.9-20.1]; p = 0.002). When stratified by NHSN risk category, periprosthetic infection risk reduction was seen in the medium-risk category (protocol: one of 402 [0.3%]; control: 25 of 1218 [2.0%]; RR, 8.3 [CI, 1.1-60.7]; p = 0.038), but no significant difference was detected in the low- and medium-risk groups (RR, 2.1 [CI, 0.5-9.6; p = 0.33] and RR, 11.3 [CI, 0.7-186.7; p = 0.09]). CONCLUSIONS: A prehospital chlorhexidine gluconate wipe protocol appears to reduce the risk of periprosthetic infections after TKA, primarily in those patients with medium and high risk. Although future multicenter randomized trials will need to confirm these preliminary findings, the intervention is inexpensive and is unlikely to be risky and therefore might be considered on the basis of this retrospective, comparative study. LEVEL OF EVIDENCE: Level III, therapeutic study.

Does Preadmission Cutaneous Chlorhexidine Preparation Reduce Surgical Site Infections After Total Hip Arthroplasty?

BACKGROUND: Periprosthetic hip infections are among the most catastrophic complications after total hip arthroplasty (THA). We had previously proven that the use of chlorhexidine cloths before surgery may help decrease these infections; hence, we increased the size of the previously reported cohort. QUESTIONS/PURPOSES: (1) Does a preadmission chlorhexidine cloth skin preparation protocol decrease the risk of surgical site infection in patients undergoing THA? (2) When stratified using the National Healthcare Safety Network (NHSN) risk categories, which categories are associated with risk reduction from the preadmission chlorhexidine preparation protocol? METHODS: Between 2007 and 2013, a group of 998 patients used chlorhexidine cloths before surgery, whereas a group of 2846 patients did not use them and underwent standard perioperative disinfection only. Patient records were reviewed to determine the development of periprosthetic infection in both groups of patients. RESULTS: Patients without the preoperative chlorhexidine gluconate disinfection protocol had a higher risk of infections (infections with protocol: six of 995 [0.6%]; infections in control: 46 of 2846 [1.62%]; relative risk: 2.68 [95% confidence interval {CI}, 1.15-0.26]; p = 0.0226). When stratified based on risk category, no differences were detected; preadmission chlorhexidine preparation was not associated with reduced infection risk for low, medium, and high NHSN risk categories (p = 0.386, 0.153, and 0.196, respectively). CONCLUSIONS: The results of our study suggest that this cloth application appears to reduce the risk of infection in patients undergoing THA. When stratified by risk categories, we found no difference in the infection rate, but these findings were underpowered. Although future multicenter randomized trials will need to confirm these preliminary findings, the intervention is inexpensive and is unlikely to be risky and so might be considered on the basis of this retrospective, comparative study. LEVEL OF EVIDENCE: Level III, therapeutic study.

A Randomized, Clinical Trial of Preadmission Chlorhexidine Skin Preparation for Lower Extremity Total Joint Arthroplasty.

BACKGROUND: Periprosthetic infections are devastating postoperative complications of total joint arthroplasty (TJA), with native skin flora commonly identified as causative organisms. We compared 2% chlorhexidine gluconate-impregnated cloths to standard-of-care antiseptic bathing in patients before TJA, to evaluate periprosthetic infection risk at 1-year follow-up. METHODS: This was a prospective, randomized, controlled trial at a single institution of patients undergoing hip or knee arthroplasty. Chlorhexidine-treated patients (275 arthroplasties) applied 2% chlorhexidine gluconate-impregnated cloths the night before and morning of admission. The standard-of-care cohort (279 arthroplasties) bathed with soap and water preadmission. Patients were excluded according to the following: (1) unable to comply with study requirements, (2) pregnant, (3) <18 years, (4) medical history of immunosuppression or steroid use, (5) chronic hepatitis B/C infection, (6) had infection around joint requiring surgery, or (7) chose not to participate. A total of 539 patients (554 arthroplasties) were included in the final population. There were no significant differences in American Society of Anesthesiologists grade, cut time, risk scores, or diabetes and smoking prevalence between cohorts (P > .05). RESULTS: A lower periprosthetic infection rate was found in the chlorhexidine cohort (0.4%) when compared to standard-of-care cohorts (2.9%). The infection odds ratio was 8.15 (95% confidence interval = 1.01-65.6; P = .049) for the standard-of-care cohort compared to the chlorhexidine cohort. No differences in assessed risk factors were found between groups. No severe adverse events were observed. CONCLUSIONS: Preoperative chlorhexidine cloth use decreased the risk of periprosthetic infection. This may be an appropriate antiseptic protocol to implement for patients undergoing lower extremity TJA.

Down Syndrome Increases the Risk of Short-Term Complications After Total Hip Arthroplasty.

BACKGROUND: Down syndrome is the most common chromosomal abnormality and is associated with degenerative hip disease. Because of the recent increase in life expectancy for patients with this syndrome, orthopaedic surgeons are likely to see an increasing number of these patients who are candidates for total hip arthroplasty (THA). METHODS: Using Nationwide Inpatient Sample (NIS) data from 1998 to 2010, we compared the short-term adverse outcomes of THA among 241 patients with Down syndrome and a matched 723-patient cohort. Specifically, we assessed: (1) incidence of THA; (2) perioperative medical and surgical complications during the primary hospitalization; (3) length of stay; and (4) hospital charges. RESULTS: The annual mean number of patients with Down syndrome undergoing THA was 19. Compared to matched controls, Down syndrome patients had an increased risk of perioperative (OR, 4.33; P<.001), medical (OR, 4.59; P<.001) and surgical (OR, 3.51; P<.001) complications during the primary hospitalization. Down syndrome patients had significantly higher incidence rates of pneumonia (P=.001), urinary tract infection (P<.001), and wound hemorrhage (P=.027). The mean lengths of stay for Down syndrome patients were 26% longer (P<.001), but there were no differences in hospital charges (P=.599). CONCLUSION: During the initial evaluation and pre-operative consultation for a patient with Down syndrome who is a candidate for THA, orthopaedic surgeons should educate the patient, family and their clinical decision makers about the increased risk of medical complications (pneumonia and urinary tract infections), surgical complications (wound hemorrhage), and lengths of stay compared to the general population.

Does Hemophilia Increase the Risk of Postoperative Blood Transfusion After Lower Extremity Total Joint Arthroplasty?

BACKGROUND: Hemophilia can lead to the development of arthropathies secondary to recurrent hemarthroses. However, given these patients' bleeding tendencies, postoperative complications associated with blood loss are a considerable concern. METHODS: We identified men in the Nationwide Inpatient Sample who underwent total hip or knee arthroplasty between January 1998 and December 2010. We used propensity scores to match 332 hemophiliacs (267 hemophilia A, 65 hemophilia B) to a comparison cohort of 996 patients in a 1:3 ratio, according to the site of arthroplasty, year of admission, age, race, and Charlson and Deyo score. RESULTS: The incidence of any postoperative transfusion was 15.06% for hemophiliacs, compared with 9.84% for the matched comparison cohort (P = .012). For hemophiliacs, the odds ratio was 1.60 (95% confidence interval [CI] = 1.11-2.31; P = .013) for any transfusion, 1.90 (95% CI = 1.24-2.92; P = .003) for allogenic transfusion, and 1.05 (95% CI = 0.56-1.95; P = .888) for autogenic transfusion. CONCLUSION: Hemophilia is associated with an increased risk of blood transfusion after lower extremity total joint arthroplasty. Patients and providers should discuss these risks before surgery, and insurers should consider incorporating this comorbidity into bundled payments for total hip and knee arthroplasty.

The Economic Impact of Periprosthetic Infections After Total Hip Arthroplasty at a Specialized Tertiary-Care Center.

BACKGROUND: Periprosthetic infections after total hip arthroplasty represent an increased risk for patient morbidity and mortality, and an increased economic burden. The purpose of this study was to compare a group of patients who had periprosthetic infections after total hip arthroplasty to a matched group of patients who underwent primary total hip arthroplasty in terms of the associated costs, length of hospitalization, and number of readmissions (within 1 year). METHODS: Between 2007 and 2011, 16 consecutive infected patients were matched to 32 noninfected patients (1:2 ratio). RESULTS: The mean episode cost, length of hospitalization, and median readmissions was significantly higher in the infected group when compared to the matched cohort: $88,623 vs $25,659, 7.6 vs 3.29 days, and 2 vs 0, respectively. CONCLUSION: Periprosthetic infections after THA resulted in an increased episode cost by approximately 3-fold, mean hospitalization period 2-fold, and led to a higher median number of readmissions.

Histopathological Evaluation of the Anterior Cruciate Ligament in Patients Undergoing Primary Total Knee Arthroplasty.

This study assessed gross and histopathological ACL changes in arthritic knees (n=174) undergoing total knee arthroplasty. Histopathological changes were assessed and graded as absent (0), mild (1), moderate (2), or marked (3). These were correlated to demographic and clinical factors, and radiographic evaluations. The ACL was intact in 43, frayed in 85, torn in 15, and absent in 31 knees. Eighty-five percent had histological changes. Overall, there were significant associations between greater age and BMI, and histological changes. Grade IV knees had significantly greater calcium pyrophosphate deposits, microcyst formation, and number of pathologic changes. These correlations may aid decision-making when determining suitability for unicompartmental or bicruciate-retaining arthroplasties, though further studies should correlate these histological findings to mechanical and functional knee status.

Barbed sutures in total hip and knee arthroplasty: what is the evidence? A meta-analysis.

INTRODUCTION: Newer methods of wound closure such as bidirectional barbed sutures hold the potential to reduce closure time and thus overall operating room costs during total joint arthroplasty (TJA), including total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, it is unclear whether these sutures have similar clinical outcomes or whether they place the patient at risk of developing wound complications that may outweigh the time-saving benefits of these sutures. METHODS: A systematic review of the literature was performed to identify all level I trials that reported the use of barbed suture during TJA. We analyzed the efficacy, safety, major and minor complications, and overall cost related to barbed sutures. RESULTS: Four studies met our criteria, and included 588 patients who were randomized either to barbed suture closure (n = 290 TJAs, 268 TKAs, and 22 THAs) or to a matched conventional suture cohort (n = 298 TJAs, 279 TKAs, and 19 THA). In terms of time savings with wound closure, the barbed suture was 6.3 minutes faster than the conventional cohort (p < 0.05). The odds for developing a minor complication were nearly identical (odds ratio [OR] 1.04, p = 0.95) and for major complication was not significantly different (OR 2.94, p = 0.27). The overall mean savings including both THA and TKA was USD 298 per case. CONCLUSIONS: In randomized controlled trials, barbed sutures are consistently associated with shorter wound closure time, which also corresponds to cost savings, even when the higher cost of these sutures is taken into account. There was no significant difference in the odds of experiencing either minor or major complications between patients in whom barbed sutures versus standard sutures were used for wound closure. Current evidence supports continued use of these sutures. LEVEL OF EVIDENCE: Level I.

Total Joint Arthroplasty in Nonagenarians: What Are the Risks?

With recent increases in life expectancy in the United States, the number of nonagenarians (age 90-99 years) presenting for lower extremity joint arthroplasty (TJA) will likely rise. Utilizing the National Surgical Quality Improvement Program database, we compared 30-day outcomes of TJA between nonagenarians and controls (age <90 years). Nonagenarians had lower mean BMI, no difference in mean number of comorbidities, and shorter mean operation time. Compared to controls, nonagenarians had longer mean length-of-stay, higher readmission rate, and higher risk of postoperative adverse events. Given these findings, orthopaedic surgeons should be aware of the increased risks of TJA in nonagenarians, and should discuss these risks with potential surgical candidates during a shared decision-making process.

Strength and Functional Improvement Using Pneumatic Brace with Extension Assist for End-Stage Knee Osteoarthritis: A Prospective, Randomized trial.

Pneumatic unloader bracing with extension assists have been proposed as a non-operative modality that may delay the need for knee surgery by reducing pain and improving function. This prospective, randomized trial evaluated 52 patients who had knee osteoarthritis for changes in: (1) muscle strength; (2) objective functional improvements; (3); subjective functional improvements; (4) pain; (5) quality of life; and (6) conversion to total knee arthroplasty (TKA) compared to standard of care. Patient outcomes were evaluated at a minimum 3 months. Braced patient's demonstrated significant improvements in muscle strength, several functional tests, and patient reported outcomes when compared to the matched cohort. These results are encouraging and suggest that this device may represent a promising alternative to standard treatment methods for knee osteoarthritis.

What Outcome Metrics Do the Various Knee Rating Systems for Assessment of Outcomes Following Total Knee Arthroplasty Measure? A Systematic Review of Literature.

Multiple scoring systems have been developed for the assessment of outcomes following total knee arthroplasty. However, few studies have comprehensively evaluated each scoring system to analyze the various outcome variables and their individual weightings toward generations of the final score. A systematic search of four electronic databases were performed from January 1960 to August, 2013 to identify studies that reported on knee scores and to sub-categorize the outcomes measured based on subjective, objective, rehabilitative, and quality of life outcomes. We also evaluated the outcome metrics that each of these systems measured to identify the relative impact of these variables toward the final score. We identified 45 different outcome metrics in 46 rating scales. Pain (80%), stiffness (13%), and swelling (13%) were the three most common subjective outcomes measured in the scoring systems, while measurements of range-of-motion (57%), flexion contracture (39%), and coronal plane deformity (35%) were the most often reported objective outcome variables. Of all the variables measured, we found that pain (mean weighted score, 26 points; range, 0 to 50 points), range-of-motion (mean weighted score, 11 points; range, 0 to 50 points), distance walked (mean weighted score, 7 points; range, 0 to 30 points), ability to climb stairs (mean weighted score, 6 points; range, 0 to 20 points), ability to rise from sitting position (mean weighted score, 4 points; range, 0 to 20 points), and presence of a flexion contracture (mean weighted score, 4 points, range, 0 to 20 points) had the greatest impact on the final score standardized to 100 points. Currently, few rating scales exist that assess all aspects of functional, rehabilitative, and quality of life outcomes including patient satisfaction within the realms of a single scoring system. Further research is needed to determine the optimal combination and weightings of the individual outcomes metrics to better evaluate overall outcomes following total knee arthroplasty and to develop a more comprehensive scoring system.

Patient Compliance with Preoperative Disinfection Protocols for Lower Extremity Total Joint Arthroplasty.

INTRODUCTION: Infection after total joint arthroplasty has been most attributed to bacterial wound contamination from skin flora. To address this, the CDC recommends bathing with an antiseptic agent the night prior to the operative day. However, despite these measures, the incidence of infections has not been reduced markedly. It is important to have measures in place to ensure proper patient education about infections and disinfection protocols to optimize compliance. Our purpose was to evaluate compliance with preoperative disinfection protocols at our institution and to identify measures which may improve adherence. MATERIALS AND METHODS: Between 2007 and 2011, we reviewed a database at our institution for all patients who underwent primary or revision total hip (n=2,458) and knee (n=2,293) arthroplasty. All of these patients were instructed to follow a chlorhexidine cloth disinfection protocol at the time of surgical scheduling or during their preoperative evaluation. To verify compliance, patients were instructed to remove adhesive stickers from the cloth packages at the time of disinfection and to affix them to the instruction sheet presented on the day of surgery. This was documented in the patient medical records. A database was generated to identify those patients who were compliant (n=1,035) or non-compliant (n=3,716). Following this period, if patients did not use chlorhexidine as instructed, the staff ensured one application was received pre-operatively. RESULTS: Approximately 78% of patients (3,716 out of 4,751 patients) were noncompliant. When evaluating the demographic between the two groups, we found that age and gender distributions were not significantly different. DISCUSSION: While preoperative decolonization protocols may reduce surgical site infections, their efficacy is limited by patient compliance and comprehension. Providing patients with thorough instructions about preoperative disinfection protocols and information about the importance of infection burden is more likely to improve patient adherence.

In-Hospital Mortality Following Open and Closed Long Bone Fracture: A Comparative Study.

BACKGROUND: Open fracture is a serious orthopaedic injury that can lead to significant patient morbidity and mortality. There is limited data on the mortality risk for open compared to closed long bone fracture. METHODS: The Nationwide Inpatient Sample was used to identify all patients who were admitted with a long bone fracture in the United States between 1998 and 2010. Cox proportional hazards regression modeling was used to calculate the hazard ratio (HR) and 95% confidence interval (CI) of mortality. RESULTS: After adjusting for age, gender, race, insurance, and comorbidities, the HR of mortality was 2.89 (95% CI, 2.56-3.28; p<0.001) for open compared to closed fracture. Stratified by anatomical site, the HR of mortality for open compared to fracture was 3.43 for femur (95% CI, 2.78-4.23; p<0.001), 2.81 for tibia or fibula (95% CI, 2.17-3.64; p<0.001), 2.54 for humerus (95% CI, 1.81-3.56; p<0.001), and 1.56 for radius or ulna (95% CI, 1.10-2.23; p=0.014). CONCLUSIONS: This data suggests that open fracture carries a worse prognosis compared to closed fracture at the same anatomical site.

Higher revision and complication rates following total hip arthroplasty in patients with inflammatory bowel disease.

The purpose of this study was to compare the clinical outcomes of total hip arthroplasty in patients with and without inflammatory bowel disease (IBD). Between 2001 and 2010, all total hip arthroplasties performed at a single institution were reviewed to identify patients who had IBD. There were 23 total hip arthroplasties in the study group, which were matched in a 1:3 ratio to 69 additional hips. At a mean follow-up of 49 months (range, 24-96 months), patients with IBD had an overall significantly lower survivorship of 87% (n = 3 revisions), compared to 98.5% (n = 1 revision) in the matched group who had a mean follow-up of 47 months (range, 24-94 months). In addition, there were significantly higher major complications in the study group (5 patients) compared to the matched group (2 patients). These results indicate that patients with IBD had an overall higher revision and complication rate.

Tobacco use may be associated with increased revision and complication rates following total hip arthroplasty.

The purpose of this study was to compare the clinical outcomes of total hip arthroplasty in patients who were smokers to patients who were non-smokers. All total hip arthroplasties performed between 2007 and 2009 were reviewed to identify patients who indicated tobacco use. There were 110 smokers who were matched in a 1:2 ratio to 220 non-smoking patients. At a mean follow-up of 51 months (range, 24 to 72 months), smokers had an overall significantly lower survivorship of 92% (n = 9 revisions), compared to 99% (n = 2 revisions) in non-smokers. In addition, there were five complications in smokers (one pneumonia, three superficial infections, and one deep peroneal nerve palsy) compared to none in non-smokers. These results indicate that patients who smoke had higher overall revisions and postoperative complications.

Clinical, objective, and functional outcomes of manipulation under anesthesia to treat knee stiffness following total knee arthroplasty.

The purpose of this study was to determine the clinical outcomes of manipulation under anesthesia (MUA) in a cohort who had developed knee stiffness following total knee arthroplasty (TKA). One-hundred and forty-five TKAs in 134 patients who had undergone MUA were compared to the remaining 1973 TKAs in 1671 patients who did not develop this condition. At a mean follow-up of 51 months (range, 24 to 85 months), the mean gains in flexion in the MUA cohort were 33° (range, 5° to 65°). The final range-of-motion in the MUA cohort was lower than the comparison cohort (114° versus 125°) however, this would meet the required flexion for activities of daily living. There were no differences in the Knee Society objective and functional scores between the two cohorts. It is encouraging that MUA cohort outcomes were comparable to outcomes of patients who did not develop knee stiffness.

Unnecessary magnetic resonance imaging of hips: an economic burden to patients and the healthcare system.

Patients referred to orthopedists for hip pain due to arthritis may already have MRI studies ordered by their referring physicians despite plain radiographs being sufficient in most cases. Hence, we prospectively evaluated every patient referred to our institution during a 36-month period to identify the number of new patients with hip osteoarthritis who had an unnecessary MRI, the additional costs of these MRIs, and the extrapolated cost to the United States healthcare system during the next 10years. Overall, 15.4% of the patients presented with unnecessary MRIs, approximately, 330 to 440.5 million dollars may be spent on unnecessary hip MRIs in this patient population in America. We believe that referring physicians should not simultaneously order a radiograph and an MRI to evaluate hip pain.