Preop X-Rays Don’t Predict TKA Patient-Reported Outcomes
OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from David Vizurraga, MD in response to a recent study in JBJS Open Access.
Whoever coined the phrase, “a picture is worth a thousand words” never treated a patient with knee osteoarthritis (OA). While knee OA is one of the most common conditions encountered in orthopaedic practice and its diagnosis and treatment are fairly straightforward, predicting the outcomes of total knee arthroplasty (TKA)—the definitive treatment for most cases of end-stage knee OA—can be challenging. The severity of OA on radiographs has long been debated as a tool to aid surgeons in predicting post-TKA outcomes and framing expectations for patients. In general, we tend to say, “The worse the x-ray, the better the patient-reported outcome,” and conversely, “The better the x-ray, the worse the patient-reported outcome.”
Lange et al. investigated this assumption in a study published in JBJS Open Access on July 9, 2020. The authors leveraged data from a 2-arm, randomized controlled trial that evaluated the role of “motivational interviewing” in enhancing rehabilitation following TKA. In their cohort analysis, Lange et al. compared pre- and postoperative WOMAC pain scores and KOOS activities-of-daily-living (ADL) scores with preoperative radiographic severity of knee OA, as measured by the Osteoarthritis Research Society International (OARSI) Atlas score. Among the 240 patients who had 2-year outcome measures and imaging available, the median preoperative OARSI score was 10 (on a scale of 0 to 18), and the authors defined “milder OA” as an OARSI score of <10 and “more severe OA” as a score of ≥10.
The researchers found a cohort-wide postoperative improvement in WOMAC pain and KOOS ADL scores of ~30 points, but they did not find any significant or clinically important differences in pain and function scores between patients with “milder OA” and “more severe OA.” The authors were also unable to demonstrate any correlation between radiographic severity and pain and function scores preoperatively.
Additionally, Lange et al. looked for associations between the WOMAC and KOOS improvements and 4 four other radiographic assessments of knee OA severity (Kellgren-Lawrence grade, compartment-specific OARSI score, compartment-specific joint-space-narrowing score, and 4-level OARSI score). Again, they failed to observe any clinically important postoperative differences in pain or function between the subjects with radiographically milder or more severe OA.
These findings provide further evidence that radiographs should represent only one piece in the puzzle of diagnosis and treatment planning for our patients with knee OA. To me, it’s worth noting that the study capitalized on data from a trial investigating motivational interviewing, which aims to improve outcomes by empowering patients—yet in the multivariable analysis that adjusted for several confounders, use of motivational interviewing was not among them. Still, the many aspects of outcome prediction following knee replacement are most definitely worthy and in need of continued investigation.
David Vizurraga, MD is a San Antonio-based orthopaedic surgeon specializing in adult hip and knee reconstruction and a member of the JBJS Social Media Advisory Board.
September 2020 Article Exchange with JOSPT
For the last 6 years, JBJS has participated in an “article exchange” collaboration with the Journal of Orthopaedic & Sports Physical Therapy (JOSPT) to support multidisciplinary integration, continuity of care, and excellent patient outcomes in orthopaedics and sports medicine.
During the month of September 2020, JBJS and OrthoBuzz readers will have open access to the JOSPT systematic review titled “Meniscus or Cartilage Injury at the Time of Anterior Cruciate Ligament Tear Is Associated with Worse Prognosis for Patient-Reported Outcome 2 to 10 Years after Injury.”
The authors of this systematic review conclude that “patients, physical therapists, orthopaedic surgeons, and athletic trainers [should] be aware that concomitant meniscus or cartilage injuries may lead to worse knee function 2 to 10 years after ACL reconstruction.”
PROM ‘Crosswalks’ Are a Big Step Forward
Patient-reported outcome measures (PROMs) for orthopaedic procedures have long been used in clinical research. In the last decade, the use of PROMs has expanded to include quality-of-care assessments and, in some healthcare systems, to help calculate costs and reimbursements. All this has made PROMs increasingly visible to patients.
There are several validated and widely used PROMs for hip and knee arthroplasty. One problem with those is that the data from one PROM are not interchangeable with data from another. That disconnect limits the opportunity for meaningful data aggregation and thwarts large-scale population research.
In the June 3, 2020 issue of The Journal, Polascik et al. tackle this problem head-on. They report on a “crosswalk” system that allows back-and-forth conversion between 4 of the most commonly used PROMS—the Oxford hip and knee scores and the HOOS and KOOS short-form scores. The authors developed this tool by applying sophisticated statistical methods to data from a large cohort of hip and knee arthroplasty patients. The accuracy of the 4 crosswalks Polascik et al. developed was substantiated when they found minimal differences between the means of the known and crosswalk-derived scores.
This practical tool for converting scores is a substantial advance in patient-reported outcomes research. It will further facilitate the pooling of data for use in future clinical research, quality-of-care initiatives, and reimbursement systems. Patients, surgeons, researchers, and health systems alike all stand to benefit greatly.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
How Many X-Rays Does It Take to Treat a Distal Radial Fracture?
We orthopaedists obtain radiographs for many reasons—to diagnose an unknown problem, to determine the progress of healing, and occasionally because we follow X-ray “dogma” acquired over time. That last reason prompted van Gerven et al. to undertake a multicenter, prospective, randomized controlled trial, the findings of which appear in the August 7, 2019 issue of The Journal.
The authors set out to evaluate the clinical utility of radiographs taken after a distal radial fracture in >300 patients. Some of those fractures were treated nonoperatively, while others underwent operative fixation. Surgeons of the patients randomized to the “usual-care” pathway were instructed to obtain radiographs at 1, 2, 6, and 12 weeks following the injury/surgery. Surgeons of patients in the “reduced-imaging” arm did not obtain radiographs beyond 2 weeks after the injury/surgery unless there was a specific clinical reason for doing so.
The authors found no significant differences between groups in any of the 6 patient-reported outcomes measured in the study, including the DASH score. Furthermore, the complication rates were almost identical between the usual-care (11.4%) and reduced-imaging (11.3%) groups. Not surprisingly, patients in the reduced-imaging group had fewer radiographs obtained (median 3 vs 4) and were exposed to a lower overall dose of ionizing radiation than those in the usual-care group.
Probably because the study was conducted in the Netherlands, it did not address the widespread practice of “defensive medicine” in the US—the unnecessary overuse of medical tests and procedures to reduce the risk of a malpractice claim. While that may limit the external validity of these findings among orthopaedists in the United States, this relatively simple yet well-designed study should remind us that it is important to have a definite clinical purpose when ordering a test of any type. A picture may be worth a thousand words, but sometimes it takes only 2 pictures to tell the full story of a healing distal radial fracture.
Chad A. Krueger, MD
JBJS Deputy Editor for Social Media
Step Monitors Yield New Insight into Ankle Surgery Outcomes
Patients considering surgery for end-stage ankle arthritis often ask which treatment—arthroplasty or arthrodesis—will help the most. Findings from various studies attempting to answer that complex question have been equivocal. In the July 3, 2019 issue of The Journal of Bone & Joint Surgery, Shofer et al. inject some objective data gleaned from step counters worn by 234 patients into this predominantly subjective question.
All patients were treated with either arthroplasty (n = 145) or arthrodesis (n = 89). Their step activity was measured with a StepWatch 3 Activity Monitor preoperatively and at 6, 12, 24, and 36 months postoperatively. In both groups combined, step counts during “high activity” (>40 steps per minute) increased by 46% over 36 months. At 6 months, the mean high-activity step improvement was 194 steps in the arthroplasty group, compared with a mean decline of 44 steps for the arthrodesis group. However, by 36 months after surgery, the between-group differences in high-activity steps had disappeared.
The authors also analyzed associations between the objective step results and 3 patient-reported outcomes (the Musculoskeletal Function Assessment and the SF-36 physical function and pain scores). Unlike the patient-reported scores, which improved dramatically in the first 6 months and then plateaued, improvements in step activity increased gradually throughout the 3-year follow-up.
The authors emphasized that during the first 12 postoperative months, the arthrodesis patients had little or no improvement in step activity, but at 3 years there were no significant differences between arthrodesis and arthroplasty patients. These findings suggest that, in this clinical scenario, an individual patient’s expectations with the pace of improvement may be a suitable topic during shared decision making conversations.
This study does not entirely reconcile previously equivocal findings regarding arthroplasty-versus-arthrodesis, but it does emphasize the substantial and sustained activity benefits that patients in both groups receive. Shofer et al. conclude that objective measurements from wearable technology “may complement patient-reported outcomes” in future longitudinal outcome studies of many orthopaedic treatments.
JBJS 100: Bankart Repair, Carpal Tunnel Assessment
Under one name or another, The Journal of Bone & Joint Surgery has published quality orthopaedic content spanning three centuries. In 1919, our publication was called the Journal of Orthopaedic Surgery, and the first volume of that journal was Volume 1 of what we know today as JBJS.
Thus, the 24 issues we turn out in 2018 will constitute our 100th volume. To help celebrate this milestone, throughout the year we will be spotlighting 100 of the most influential JBJS articles on OrthoBuzz, making the original content openly accessible for a limited time.
Unlike the scientific rigor of Journal content, the selection of this list was not entirely scientific. About half we picked from “JBJS Classics,” which were chosen previously by current and past JBJS Editors-in-Chief and Deputy Editors. We also selected JBJS articles that have been cited more than 1,000 times in other publications, according to Google Scholar search results. Finally, we considered “activity” on the Web of Science and The Journal’s websites.
We hope you enjoy and benefit from reading these groundbreaking articles from JBJS, as we mark our 100th volume. Here are two more:
The Bankart Procedure: A Long-Term End-Result Study
C R Rowe, D Patel, W W Southmayd: JBJS, 1978 January; 60 (1): 1
This was the first large clinical series with long follow-up to report the findings and results of the open Bankart repair. The results were almost uniformly excellent or good, and this study contributed to the demise of nonanatomic shoulder repairs.
A Self-Administered Questionnaire for the Assessment of Severity of Symptoms and Functional Status in Carpal Tunnel Syndrome
D W Levine, B P Simmons, M J Koris, L H Daltroy, G G Hohl, A H Fossel, J N Katz: JBJS, 1993 January; 75 (11): 1585
Distinguishing interventions that work from those that don’t requires rigorous outcomes research, which, in turn, relies on standardized, patient-centered measures that have proven reliability and validity. Meeting these criteria are the Symptom Severity and Functional Status Scales for carpal tunnel syndrome described in this oft-cited JBJS study from 25 years ago.
The True “Bottom Line” for Advanced Technology: Patient Outcomes
Orthopaedic surgery has been blessed with an explosion of diagnostic and therapeutic technology over the last several decades. Improvements in advanced imaging, minimally invasive surgical techniques, and biomaterials and implant design have resulted in both perceived and objectively measurable patient benefits. In many cases, these benefits have been documented with patient-reported functional outcome data as well as improved clinical outcomes such as range of motion, strength, return to work, and pain relief.
However, some of these technological advances serve as expensive substitutes for many of the basic procedures that are universally available at a fraction of the cost, such as taking a thorough history, performing a complete physical examination, and employing basic and time-tested surgical techniques when indicated. While new minimally invasive techniques and computer-assisted preoperative planning are impressive in many respects, it is important to remember the ultimate goal of any orthopaedic operation: improving the patient’s musculoskeletal function.
In the July 18. 2018 issue of The Journal, Buijze et al. examine results from a multicenter randomized trial that compared patient-reported outcomes after using either 2-dimensional (standard radiographs) or 3-dimensional (CT with computer assistance) planning for corrective osteotomy in patients with a distal radial malunion. Although post-hoc analysis revealed that this study was underpowered, the patient-reported outcomes (as measured by DASH and PRWE) were not significantly different between the two preoperative planning groups.
These findings do not mean that advanced technology does not have a place in preoperative planning, but for me the findings emphasize that the most important factors in any orthopaedic surgery are the surgeon’s judgment, skill, and experience. When a surgeon needs assistance maximizing one of those three variables, more advanced technologies may play a role in improving patient outcome. For example, among less experienced surgeons, I suspect that more detailed preoperative planning for a relatively uncommon procedure would improve patient outcome, but it would probably have little impact on the results of procedures performed by more experienced surgeons.
The authors of this study focus on the true bottom line for any surgical intervention: patient outcome. But the other bottom line must also be considered. With the per-procedure incremental cost of 3-D planning and patient-specific surgical guides for upper-extremity deformity corrections estimated to range between $2,000 and $4,000, we must continue to conduct this type of Level I research. For the days of laying one “advance” on top of another with no attention paid to the cost for individual patients and the overall system are long gone.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Can Only 4 Questions Yield Meaningful Patient Outcome Measures?
In today’s data-driven, evidence-based world of orthopaedics, capturing accurate information about a patient’s physical function can require patients to answer dozens of separate questions. In the June 7, 2017 edition of JBJS, Hancock et al. investigate whether the computer-based tool called PROMIS (Patient-Reported Outcomes Measurement Information System) PF CAT is more efficient than and just as reliable as the more burdensome function-evaluation instruments.
In short, the answer is yes. Among a group of otherwise healthy patients scheduled to undergo meniscal surgery, the PROMIS PF CAT scores were generally highly correlated with traditional patient-reported physical-function measures, such as the SF-36 Physical Function instrument and the KOOS Sport and Quality-of-Life scores.
In contrast to the more traditional fixed-length questionnaires, the PROMIS PF CAT presents an initial item to the patient, and uses the response to that to select the most informative next item. That process continues only until a predefined level of precision is reached, at which point the test ends. The vast majority (89%) of the patients in this study completed the PROMIS PF CAT after answering only four items.
Considering its strong correlation with other widely accepted measurement tools and its efficiency, the authors conclude that PROMIS PF CAT “may be a good alternative for evaluating physical function in meniscal injury populations,” and that it could help “reduce burnout and maintain high response rates” in a time-constrained health care environment.
JBJS Classics: Fractures of the Talar Neck
OrthoBuzz regularly brings you a current commentary on a “classic” article from The Journal of Bone & Joint Surgery. These articles have been selected by the Editor-in-Chief and Deputy Editors of The Journal because of their long-standing significance to the orthopaedic community and the many citations they receive in the literature. Our OrthoBuzz commentators highlight the impact that these JBJS articles have had on the practice of orthopaedics. Please feel free to join the conversation by clicking on the “Leave a Comment” button in the box to the left.
One of the most challenging diagnoses for general orthopedic surgeons as well as fracture specialists is a fracture of the talar neck. The infrequency of displaced talar fractures means that orthopaedic residents receive relatively little training in this area. A pivotal JBJS article in 1978 focused attention on these vexatious injuries. “Fractures of the Neck of the Talus” by Canale and Kelly provides clinically useful information and does two things that are very difficult to do today:
- Follows patients for a long time (an average of nearly 13 years)
- Obtains direct evidence of outcomes by physical exam, one-on-one measurement, and long-term imaging.
This remarkable duration of follow-up, so important in determining the impact of treatment in musculoskeletal injury, is very difficult today as a result of overly enthusiastic privacy protections and a costly regulatory infrastructure.
This classic JBJS article capitalizes on other classics, such as those by Blair (1943) on talar body salvage and studies by Halliburton (1958) and Mulfinger (1970) on the anatomy of talar blood supply. While Mulfinger showed the vascular supply of the talus,1 that study did not link that information to clinical care. The study by Canale and Kelly provides insight into how our care for patients with these uncommon fractures affects outcomes. In addition, the relatively primitive state of art at the time for the operative treatment of talar fractures led to fear of infection, and limited understanding of the basics of fracture healing and underdeveloped implants for fixation steered many surgeons away from rigid fixation in favor of closed reduction and cast immobilization.
The authors identified 107 fractures treated over a 33-year period; they examined and obtained radiographs on 71 of those fractures in 70 patients at an average follow-up of almost 13 years. (Fourteen of the patients were followed for more than 20 years, and 5 were followed for more than 30 years.) The preferred treatment protocol was closed reduction and casting. A reduction with less than 5 mm of displacement and 5° of misalignment was considered adequate. Open reduction with internal fixation was performed when these criteria were not met.
To assess outcomes, the authors directly measured ankle and subtalar motion, assessed whether a limp was present, and asked patients to rate their pain. Long before “patient-reported outcome measures” was a recognized term, these authors recorded them. Only 59% of patients in this series achieved good or excellent outcomes. The authors identified the high morbidity of these injuries, including avascular necrosis in more than half and 25 who needed later surgical intervention. The authors also recommended against talectomy as a salvage procedure.
While hampered by relatively low-resolution imaging and outcome measures that don’t meet current standards of reproducibility, Canale and Kelly provided a great deal of information that focused attention on the importance of quality of reduction. In addition, the paper created an enduring fracture classification that paralleled complication rates and potential outcomes.
Bruce Sangeorzan, MD
JBJS Deputy Editor
Reference
- Mulfinger GL, Trueta J. The blood supply of the talus. J Bone Joint Surg Br. 1970 Feb;52(1):160-7
Nebulous Controls, Noncompliance Mar JAMA Low Back Pain Study
OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from Brett A. Freedman, MD, in response to a recent JAMA study on treatment for chronic low back pain.
Chronic low back pain (CLBP) is truly a bio-psycho-social disease. Cherkin et al. in the March 22/29, 2016 issue of JAMA published a randomized clinical trial comparing the performance of two psychologically focused interventions for CLBP with usual care.
The authors randomly assigned 342 subjects solicited from an integrated health plan in the state of Washington who had at least 3 months (average 7.3 years) of nonspecific CLBP to one of three cohorts: mindfulness-based stress reduction (MBSR), cognitive behavioral therapy (CBT), or usual care. MBSR is a pain self-management program that incorporates yoga and focuses on “increasing awareness and acceptance of moment-to-moment experiences.” The two therapy arms included eight 2-hour sessions.
The primary and secondary outcomes were computed values on patient-reported outcome (PRO) instruments compared from baseline out to one year. According to intention-to-treat analysis, MBSR and CBT resulted in a significantly higher chance of patients obtaining a clinically meaningful response, which equated to a >30% improvement in scores on the modified Roland Disability Questionnaire at 26 weeks after enrollment (61% for MBSR vs. 58% for CBT vs. 44% for usual care).
While these findings are interesting and support the notion of more research into non-pharmacological and non-interventional CLBP treatment, the impact of this study is limited by inherent flaws. The investigators’ intent was to have the usual care group represent a control group. However, the usual care cohort was far from controlled. At the time of enrollment, those randomized to the usual care cohort were each given $50 and were set free to “seek whatever treatment [for their CLBP], if any, they desired.” The resultant placebo effect of receiving active treatment (i.e. MBSR, CBT) versus no prescribed treatment (i.e. usual care cohort) is substantial.
Also, aside from reporting their collected PRO data, the authors say little about what happened to the usual care group during this trial, further making this cohort too nebulous to serve as a meaningful comparator. If this cohort is excluded from the analysis, this becomes a negative-findings study, since there were no significant differences in any measured outcome between the MBSR and CBT cohorts, aside from mental health measures, which were significantly improved following CBT.
Another major flaw is the very high rates of patient noncompliance with treatment. Only 51% of the subjects in the 2 therapy arms attended at least 6 of the sessions, and 13 subjects (11%) in each of the active-therapy groups attended no sessions. A substantial minority of patients failed to meaningfully participate in their prescribed intervention, yet their improved outcomes are attributed to the impact of these programs. If the same lack of adherence to protocol occurred in a pharmacological or surgical study, the results would be ignored and the article would likely go unpublished, or at least not published in a high-impact journal such as JAMA.
In conclusion, the greatest merit of this study is the research question it poses. We certainly need more work on this subject, but unfortunately this particular study does little to further advance our understanding of the best practices for approaching the bio-psycho-social disease we call CLBP.
Brett A. Freedman, MD is an orthopaedic surgeon specializing in spine trauma and degenerative spinal diseases at the Mayo Clinic in Rochester, MN.
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