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The Economics of Revision THA for Fractures: Sustainable?

At the risk of  economic oversimplification, it is difficult to sustainably provide a service when payment for it is less than the cost to perform it. But that is one reality exposed by Hevesi et al. in the May 15, 2019 issue of The Journal. Using National Inpatient Sample and ACS-NSQIP data, the authors compared the average costs and 30-day complication rates for revision total hip arthroplasties (THAs) performed for 3 different indications—fractures, wear/loosening, and instability—at both a local and national level. They found that the average hospitalization costs associated with a revision THA related to a fracture were 33% to 48% higher (p < 0.001) than the cost of revision THAs related to wear or instability.

However, the authors emphasize that all 3 of these indications for revision THA are reimbursed at the same rate based on Medicare Diagnosis-Related Group (DRG) codes. DRGs take into account patient comorbidities to determine reimbursement levels—but they do not adjust payments for THA revision according to indication. Hevesi et al. note that the only DRG reimbursement level that would cover the average cost of a revision THA for a fracture would be one performed on a patient with severe medical comorbidities or a major complication. Not surprisingly, patients who underwent a revision THA to treat a fracture were found to have a higher age and more medical comorbidities than those undergoing a revision for wear or instability.

The authors use this data to make a very compelling case that DRGs for revision THA should be changed so they are indication-specific, taking into account the underlying reason for the revision. They observe that “a DRG scheme that does not distinguish between indications for revision THA sets the stage for disincentivizing the care of fracture patients and incentivizing referrals to other facilities.” Those “other facilities” usually end up being large tertiary-care centers, which the authors claim “perform a higher percentage of the costlier revision THA indications.”

This problem of reimbursement inequality is not unique to revision THAs and requires further investigation in many fields. Unless “the system” addresses these subtle but important differences, tertiary referral centers may be inundated with patients who need procedures that cost more to perform than the institutions receive in reimbursement—an unsustainable scenario.

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media

Which Germs Cause Pelvic Prosthesis Infections?

Prosthetic infections involving total hip or knee implants are bad enough, but infections involving pelvic endoprostheses following tumor resection can be particularly devastating, often necessitating multiple surgical interventions. And, such infections are disconcertingly common, affecting an estimated 11% to 53% of pelvic endoprostheses.

Findings from a retrospective multisite cohort study by Sanders et al. in the May 1, 2019 issue of The Journal of Bone & Joint Surgery reveal more about the specific microorganisms underlying those infections—and may offer insight into how to prevent them.

The authors analyzed 70 patients who underwent pelvic endoprosthetic reconstruction following a tumor resection. Eighteen patients (26%) developed an infection, and in 14 out of those 18 cases, the infection was determined to be polymicrobial. Cultures from 12 of the 18 patients (67%) were positive for a member of the Enterobacteriaceae family of gram-negative bacteria, which includes Escherichia coli. More generally, microorganisms associated with intestinal flora appeared 32 out of the 42 times that any microorganism was isolated.

At the latest follow-up (median follow-up was 66 months), 9 of the 18 patients still had the original implant, although 2 of those patients had a fistula and another 2 were receiving suppressive antibiotics. Of the remaining 9 patients who had the original implant removed, 3 had a second implant in situ.

The authors emphasize how different these pelvic endoprosthetic infections are from infections related to joint arthroplasty. The close proximity of incisions for periacetabular tumor resection to the gut and other highly colonized areas might contribute to these infections, they speculate. Sanders et al. say the findings of this study may prompt surgeons to employ additional surgical-site antiseptic measures before and during these surgeries and “may justify the use of a broader spectrum of [systemic] antibiotic prophylaxis aimed at gram-negative bacteria.”  They also suggest that investigations into “selective gut decontamination” might yield additional information about how to prevent infections in this surgical setting.

A Rash of Broken Femoral Nails—What’s Up?

I’ll be honest: I have never worried much about breakage of the cephalomedullary nails I implant for proximal femur fractures. Instead, I’m focused on the fracture reduction, soft-tissue handling, and proper implant positioning. These nails are very strong. Sure, failures of these implants may occur and have been reported. But I have never had a lengthy discussion with a patient about the potential risk of the implant breaking during normal activity—and I doubt many other surgeons have either.

That is why the article by Lambers et al. in the May 1, 2019 issue of The Journal grabbed my attention. The authors carefully analyzed 16 cases in which a specific cephalomedullary nail (the TFNA, made from a titanium-molybdenum alloy) broke in 13 patients after an average of 5 months. Of note, 3 patients who underwent a revision with the same type of nail had a repeat fracture of the implant. The majority of these patients had been treated for a reverse oblique intertrochanteric fracture —a type that we all commonly see and treat—and all the fractures had been well reduced at the time of nail insertion.

The implant fractures all occurred at the proximal aperture of the nail and were consistent with fatigue fracture of the alloy. But they all showed a unique “stepped propagation” pattern, whereby, according to the authors, “a planar crack arrested, changed planes by 90°, progressed, arrested, and then changed planes again by 90° until final failure.”

These types of implant failures are not common for this nail, but they apparently happen more often than I thought. I am certain that the manufacturer will be responding to this data, and I look forward to future design changes—especially because the authors hypothesize that prior changes to this nail’s design and/or alloy may have contributed to these breakages. Then again, there may have been errors in technique that made these types of failures more common, or maybe a different implant would have been a better choice for some of these patients. To me, matching fracture type and implant choice is very important.

I look forward to learning more about this issue and will keep these types of implant failures in the back of my mind during hip-fracture cases. In the meantime, Lambers et al. advise “vigilant clinical and radiographic surveillance of patients with unstable hip fracture patterns who undergo osteosynthesis with use of a TFNA implant.”

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media

Shared Decision Making among Guatemalan Orthopaedists

The concept of asking and accounting for patient preferences in non-emergent treatment decisions has been discussed in the medical literature for nearly two decades. Michael J. Barry, MD and others have quite fully developed this notion of “shared decision making” (SDM). In the context of patient desires, SDM includes a presentation of the treatment options and the data regarding those treatment options, and a discussion of potential complications involved in each option.

The earliest work on SDM centered around patient choices for managing prostate disease, degenerative disc disease of the lumbar spine, and urinary incontinence. Only recently have orthopaedic surgeons embraced this concept, as more of us get training in and practice the necessary communication skills and cultural competency needed to engage our patients in SDM. But we still have a long way to go when it comes to facility with SDM, and this seems to be especially true in the orthopaedic communities of some non-US countries.

In the May 1, 2019 issue of The Journal, Martinez-Siekavizza et al. report results of a survey on the use of SDM among orthopaedic surgeons in Guatemala. Survey recipients were questioned about their SDM techniques in the clinical scenario of intertrochanteric hip fracture, although hip fracture may not have been the ideal condition to focus on, given the worldwide acceptance that this condition is almost always best managed surgically. Nevertheless, the survey showed that 25% of the surgeon respondents ”never” or “hardly ever” allowed their patients to participate in the treatment decision-making process. While the authors cite many systemic reasons for such lack of patient participation (such as surgical consent not being required in Guatemala and the limited resources in many rural areas of the country that often leave no choices available), 75% non-engagement with patients/families strikes me as very high.

The key facet of shared decision making is discussing all the potential treatment options with the patient. This aspect of SDM seems especially important for nontrauma elective cases in which the “best” treatment option may be less clear than in trauma cases.  Even so, Martinez-Siekavizza et al. found that surgeons who discussed the different treatment options with patients had an almost 3-fold greater likelihood of allowing patients to participate in decision making than those who did not. This makes intuitive sense, as it would be difficult for patients to take part in treatment decisions if they are not informed about the options that exist.

As surgeons, we need to do our best to ensure that patients understand all their treatment options, and we should sharpen our focus on shared decision making during our patient interactions. JBJS looks forward to receiving more manuscripts from all over the world that explore the techniques and value of SDM in orthopaedic patient management.

Marc Swiontkowski, MD
JBJS Editor-in-Chief

VTE Prevention: Is Aspirin Really That Good?

OrthoBuzz occasionally receives posts from guest bloggers. In response to a three recent studiesthe following commentary comes from Jeffrey B. Stambough, MD.

Throughout the last decade, we’ve experienced a boom in anticoagulation options to help prevent venous thromboembolism (VTE) associated with orthopaedic procedures. The use of aggressive anticoagulation, such as warfarin and various heparin formulations, is being questioned, largely due to concerns about bleeding risks and wound complications.  Along with the newer direct oral anticoagulants such as rivaroxaban, over-the-counter aspirin (ASA) is gaining prominence as an anticoagulant due to its high efficacy, low cost, convenience for patients, favorable side-effect profile, and cardioprotective attributes.  Current guidelines include the use of all these thromboprophylactic agents, but three recent studies lend credence to using aspirin as the primary VTE prophylactic agent when performing total joint arthroplasty (TJA).

In a  March 20, 2019 JBJS study analyzing >31,000 TJAs performed at a single institution over 17 years, Rondon et al. found a 3-fold lower 30-day and 2-fold lower 1-year mortality rate in patients receiving ASA (81mg or 325 mg twice daily), compared to those who received non-aspirin thromboprophylaxis (mainly warfarin).  No mortality differences were noted between the two ASA dosing regimens.  While investigating specific causes of death, the authors discovered that the primary cause of death in the non-ASA cohort was cardiac related at all time points.

A second study, from the April 3, 2019 JBJS, looked into the effects of 3 antithrombotic agents on symptomatic VTE rates and periprosthetic infections in high-risk patients undergoing primary or revision TJA.  When compared to the two more potent agents (warfarin and low-molecular-weight heparin), ASA proved more effective at reducing pulmonary embolism (PE) and VTE rates in high-risk patients, and it was also associated with lower rates of periprosthetic joint infection when compared with warfarin.  Thus, it seems that even in patients deemed to be higher risk for developing VTE, ASA may be a safe, effective option.

Lastly, Runner et al. gleaned VTE prophylaxis data from >22,000 TJA cases submitted by surgeons sitting for Part 2 of ABOS between 2014 and 2016.  The findings, reported in the April 2019 issue of the Journal of Arthroplasty, showed similar trends to those seen in the two previously mentioned studies: Mild (distal or superficial deep vein thrombosis [DVT]), moderate (nonfatal PE, proximal DVT) and severe (fatal PE) VTE events, as well as death, were significantly less frequent in those who received ASA compared to more aggressive agents (heparin or one of its analogs, direct oral agents, or warfarin). Also, patients who received ASA with or without mechanical prophylaxis had significantly lower complication rates (95.5% vs. 93.0%, p<0.001).

One firmly held dogma in medicine is that patients who are at higher risk for VTE should be treated with stronger anticoagulation medications. However, these 3 studies support the idea that less aggressive anticoagulation medication (specifically, low-dose aspirin) may be the more effective and safer option for most patients. In our ongoing quest to improve patient outcomes and mitigate risk around the TJA episode, we should consider using aspirin for thromboprophylaxis unless there is an explicit contraindication in a specific patient.

However, we should also keep in mind that these three studies have the common limitations of all retrospective analyses. Recent randomized trials have shown aspirin to be “noninferior” to other anticoagulants for VTE prevention, and in less than 2 years, we should have even more definitive answers to this question from the randomized, multicenter PEPPER trial, with its estimated 25,000 participants.

Jeffrey B. Stambough, MD is an orthopaedic hip and knee surgeon, an assistant professor of orthopaedic surgery at University of Arkansas for Medical Sciences, and a member of the JBJS Social Media Advisory Board.

Diagnosing PJI: When The “Urine Dipstick” Outperforms Conventional Labs

Despite what seems like a new, high-quality study being published on the topic every week or so, orthopaedic surgeons still have an extremely hard time determining whether a prosthetic hip or knee is infected or not. We have an array of available tests and the relatively easy-to-follow criteria for a periprosthetic joint infection (PJI) from the Musculoskeletal Infection Society (MSIS), but a large number of these patients still fall into the gray zone of “possibly infected.” This predicament is especially thorny in patients who received antibiotics just prior to the diagnostic workup, which interferes with the accuracy of many tests for PJI.

In the April 17, 2019 issue of The Journal, Shahi et al. remind orthopaedic surgeons about a valuable tool that can be used in this scenario. Their retrospective study looked at 121 patients who had undergone revision hip or knee arthroplasty due to an MSIS criteria-confirmed periprosthetic infection. Shahi et al. sought to determine which diagnostic tests were least affected by prior antibiotic administration. The authors found that erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) level, synovial white blood cell (WBC) count, and polymorphonuclear neutrophil (PMN) percentage were all significantly lower in the 32% of patients who had received antibiotics within 2 weeks of those tests, compared with the 68% who did not receive antibiotics. The only test that was found not to be significantly affected by the prior admission of antibiotics was the urine-based leukocyte esterase strip test.

Considering the ease and rapidity with which a leukocyte esterase test can be performed and evaluated (at a patient’s bedside, with immediate results), its low cost, and the fact that it is included in the MSIS criteria, these findings are very important and useful. While we would prefer that patients with a possibly infected total hip or knee not receive antibiotics prior to their diagnostic workup, previous antibiotic exposure remains a relatively common scenario. The findings from this study can assist us in those difficult cases, and they add further evidence to support the value and reliability of the easy-to-perform leukocyte esterase test.

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media

What’s New in Sports Medicine 2019

Every month, JBJS publishes a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of all OrthoBuzz Specialty Update summaries.

This month, Albert Gee, MD, a co-author of the April 17, 2019 “What’s New in Sports Medicine,” selected the five most clinically compelling findings from among the 30 noteworthy studies summarized in the article.

Anterior Cruciate Ligament (ACL) Reconstruction

–Norwegian researchers randomized 120 patients to undergo either single-bundle or double-bundle ACL reconstruction and followed them for 2 years.1 They found no difference between the 2 techniques in any patient-reported outcome, knee laxity measurements, or activity levels. These results, along with the preponderance of evidence from other comparative trials over the last 5 years, strongly suggest that routine use of 2 bundles to primarily reconstruct a torn ACL adds no clinical benefit over a well-positioned single-bundle reconstruction.

Knee Cartilage Repair

–A randomized study compared long-term patient outcomes after knee cartilage repair using microfracture versus mosaicplasty.2 Included patients had 1 or 2 focal femoral lesions measuring between 2 and 6 cm2. Better outcomes after a minimum of 15 years of follow-up were found in the mosaicplasty group. Although there were only 20 patients in each arm, the Lysholm-score differences between the groups were both clinically important and statistically significant. More patients in the mosaicplasty group than in the microfracture group said they would have the surgery again, knowing their 15-year outcome.

Rotator Cuff

–UK researchers randomized 313 patients with ≥3 months of subacromial pain and an intact rotator cuff who had completed a nonoperative program of physical therapy and injection to 1 of 3 groups: arthroscopic subacromial decompression, diagnostic arthroscopy (“sham” surgery), or no intervention.3 At 6 months and 1 year, all groups demonstrated statistically significant and clinically important improvement, but patient-reported outcome scores were significantly better in both surgical groups compared with the no-treatment group. The data suggest that patients such as these improve over time, regardless of management, but that surgical decompression  may offer a slight benefit over nonoperative management because of the placebo effect.

–A randomized controlled trial investigated the effect of a formal preoperative education program (2-minute video plus handout)4 about postoperative narcotic use, side effects, dependence risk, and addiction potential among >130 patients undergoing arthroscopic rotator cuff repair surgery. The education group consumed 33% less narcotic medication at 6 weeks and 42% less at 12 weeks compared with the control group. Among the more than one-quarter of the patients who had used opioids prior to surgery, those randomized to the education group were 6.8 times more likely than controls to discontinue narcotic use during the study period.

Hip Arthroscopy

–A randomized controlled trial of >300 patients compared hip arthroscopy and “best conservative care” for treating femoroacetabular impingement (FAI).5 Only 8% of patients crossed over from conservative care to the surgical group. The mean adjusted difference in iHOT-33 scores at 1 year was 6.8, in favor of hip arthroscopy. However, adverse events were more frequent in the arthroscopy cohort, and a within-trial economic evaluation suggested that hip arthroscopy was not cost-effective compared with conservative care during the 1-year trial period.

References

  1. Aga C, Risberg MA, Fagerland MW, Johansen S, Trøan I, Heir S, Engebretsen L. No difference in the KOOS Quality of Life Subscore between anatomic double-bundle and anatomic single-bundle anterior cruciate ligament reconstruction of the knee: a prospective randomized controlled trial with 2 years’ follow-up. Am J Sports Med.2018 Aug;46(10):2341-54. Epub 2018 Jul 18.
  2. Solheim E, Hegna J, Strand T, Harlem T, Inderhaug E. Randomized study of long-term (15-17 years) outcome after microfracture versus mosaicplasty in knee articular cartilage defects. Am J Sports Med.2018 Mar;46(4):826-31. Epub 2017 Dec 18.
  3. Beard DJ, Rees JL, Cook JA, Rombach I, Cooper C, Merritt N, Shirkey BA, Donovan JL, Gwilym S, Savulescu J,Moser J, Gray A, Jepson M, Tracey I, Judge A, Wartolowska K, Carr AJ; CSAW Study Group. Arthroscopic subacromial decompression for subacromial shoulder pain (CSAW): a multicentre, pragmatic, parallel group, placebo-controlled, three-group, randomised surgical trial. Lancet. 2018 Jan 27;391(10118):329-38. Epub 2017 Nov 20.
  4. Syed UAM, Aleem AW, Wowkanech C, Weekes D, Freedman M, Tjoumakaris F, Abboud JA, Austin LS. Neer Award 2018: the effect of preoperative education on opioid consumption in patients undergoing arthroscopic rotator cuff repair: a prospective, randomized clinical trial. J Shoulder Elbow Surg.2018 Jun;27(6):962-7. Epub 2018 Mar 26.
  5. Griffin DR, Dickenson EJ, Wall PDH, Achana F, Donovan JL, Griffin J, Hobson R, Hutchinson CE, Jepson M,Parsons NR, Petrou S, Realpe A, Smith J, Foster NE; FASHIoN Study Group. Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial. Lancet. 2018 Jun 2;391(10136):2225-35. Epub 2018 Jun 1.

Durability of Constrained Liners in Revision THA

The indications for treating total hip arthroplasty (THA) dislocations by cementing a constrained polyethylene liner into a well-fixed, retained acetabular component at the time of revision are narrow. That’s largely due to concerns about the durability of the resulting acetabular construct. Now, thanks to a study by Brown et al. in the April 3, 2019 issue of JBJS, hip surgeons have some hard data about the long-term outcomes of this approach.

After reviewing 125 cases in which a constrained liner was cemented into a retained, osseointegrated acetabular component during revision THA, with a mean follow-up of 7 years, the authors found that:

  • Survivorship free from revision for instability was 86% at 5 years and 81% at 10 years. The cumulative incidence of instability at 7 years was 18%.
  • Survivorship free from aseptic acetabular component revision was 78% at 5 years and 65% at 10 years. The most common failure mechanism was dissociation of the constrained liner from the retained component.
  • Harris hip scores (HHS) did not improve significantly after revision. This finding is consistent with prior research that shows better post-revision HHS scores in patients whose revisions include the entire acetabular component.
  • Position of the retained cup did not affect implant survivorship or risk of dislocation.

The authors mention alternative strategies for reducing the risk of dislocation after revision THA, such as the use of large-diameter heads and dual-mobility constructs. Still, they conclude that this constrained-liner approach, in the setting of a relatively well-positioned acetabular component, is a viable and durable THA revision option, especially for those “with a compromised abductor mechanism, recurrent instability, [and] a well-fixed and well-positioned acetabular component, for whom an acetabular revision would not be tolerated.”

Doc, Will My New Joint Outlive Me?

When discussing total joint replacement (TJR) with patients, I and most other surgeons who perform TJRs are invariably asked, “How long will my new hip last?’” or “Will I need to replace this new knee with another one if I live to be 90?” Although these important questions have essentially been studied since the implants and procedures were first developed, precise answers are still hard to come by. That’s largely because many factors can affect the longevity of an implant, including the implant material and design and the patient’s size/weight, activity level, and comorbidities. Also, many patients die before their joints wear out, and their data is often not captured accurately by researchers and registries. It is therefore difficult to give patients anything better than rough-estimate answers.

That is why I was interested to read two recently published systematic reviews in The Lancet. The reviews—one focused on knee replacement and the other on hip replacement—evaluated studies from six different non-US countries with robust joint registries in an effort to answer these “how long” questions. Based on the authors’ pooled analysis of registry data, the reviews found that:

  • Nearly 60% of >215,000 hip replacements lasted 25 years, 70% lasted 20 years, and almost 90% lasted 15 years.
  • The nearly 300,000 total knee replacements evaluated lasted even longer: 82% lasted 25 years, 90% lasted 20 years, and 93% lasted 15 years.

While these data are helpful, they do still not provide specific answers for the many individuals who may not be “standard” patients, and they do not take into account advances in implant designs and materials that have occurred over 25 years. However, as registry data becomes more ubiquitous and robust, especially in the United States with the growth of the American Joint Replacement Registry, I believe these questions will be answered with increased specificity for individual patients.

Chad A. Krueger, MD
JBJS Deputy Editor for Social Media

Don’t Overlook Possible Osteoid Osteoma in Kids with Hip Pain

Orthopaedists are seeing an increasing number of active, young patients with hip pain. A study by May et al. in the March 20, 2019 issue of The Journal of Bone & Joint Surgery strongly suggests that osteoid osteoma (OO)—a small, benign tumor characterized by dense sclerotic bone tissue—should not be overlooked in the differential diagnosis when working up these patients.

The authors identified and reviewed the records of 50 children and adolescents (mean age of 12.4 years) at their tertiary-care pediatric center who had received a diagnosis of OO within or around the hip between 2003 and 2015. Nighttime hip and/or thigh pain (90%) and symptom relief with NSAIDs (88%) were common clinical findings.

Sclerosis/cortical thickening was visible in 58% of the radiographs. Perilesional edema and a radiolucent nidus was found on all 43 of the available CT scans, leading the authors to conclude that “CT scans provide definitive diagnosis” of OO.

Unfortunately, 46% of these patients initially received an alternative diagnosis, the most common of which was femoroacetabular impingement (FAI), and a delay in diagnosis of >6 months occurred in 43% of patients. The authors note that concerns regarding radiation exposure have led some clinicians to order MRI rather than CT when evaluating pediatric hip disorders, but this study found that identifying an OO nidus with MRI was not as accurate as doing so with CT.

Regarding treatment, among the 41 patients who ultimately underwent percutaneous radiofrequency ablation (RFA) to treat OO, 93% achieved complete post-RFA symptom resolution. Complications from RFA occurred in 7% of patients who underwent the procedure.