New Findings in Muscle Injury—An Under-Researched Subject
The goal of orthopaedic surgery is to help the entire musculoskeletal system function in harmony, but the preponderance of orthopaedic research focuses on the skeletal system instead of muscles and tendons. Bone is the only organ that can heal by regenerating tissue that is usually just as effective as the original structure. Consequently, we have focused on developing systems to hold bone intact as it heals so that postinjury function is maximized. Decades have been spent understanding the critical biologic pathways of bone healing and developing implantable, pharmacologic, and cell-based therapies to optimize it.
However, we sometimes overlook the fact that the skeleton can’t move without muscles. Only a few researchers have devoted their careers to understanding skeletal muscle’s response to injury and approaches to enhance muscle recovery after disuse and injury. In the August 15, 2018 issue of The Journal, Hara et al. report on experiments with the protein periostin in mice. Periostin is involved with the process of muscle fibrosis, during which fibroblasts proliferate in the injured area of the muscle and create “scar tissue” that eventually inhibits muscle function.
In one experiment, the authors found that “knockout” mice without the gene that encodes for periostin had improved recovery in a lacerated gastrocnemius muscle, less fibrosis in the muscle, and a significantly reduced number of infiltrating fibroblasts than “wild” mice with the same induced injury. In a similar experiment, they found reduced muscle fibrosis in injured muscles of mice whose production of periostin was neutralized by an antibody injected into the injured muscle. Although a sharp injury to muscle (the laceration model used in these mouse experiments) is not a common clinical scenario in patients seen by orthopaedists, the Hara et al. study represents a step forward in understanding muscle response to injury.
While these findings need to be replicated and then translated into clinical applications for humans, they shed new light on the importance of preventing periostin-induced fibroblast migration after skeletal muscle injury. This research hints at a potential therapeutic strategy to enhance muscle’s functional recovery, which is the most sought-after outcome for patients.
The clinical sports and orthopaedic communities are in need of approaches to limit scarring and atrophy in the setting of muscle disuse and injury. Any of us who unavoidably injure muscle during surgical approaches to bones and joints or for graft harvests and other procedures should be heartened by these findings. It is my hope that more early-career researchers will focus on the first half of the term “musculoskeletal” to advance therapeutic approaches to problems that impact function to a much more permanent degree than do most bone injuries.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
More Evidence of Patient Benefits with Cross-Linked Polyethylene
In an OrthoBuzz post last year titled “Has Conventional Polyethylene Become Obsolete?,” we featured results from a small randomized trial that documented much-improved implant survival over 10 years with acetabular components made from cross-linked polyethylene (XLPE) compared with conventional polyethylene (CPE). In the August 1, 2018 issue of The Journal, we find further corroboration of the benefits realized by patients who receive XLPE acetabular components.
deSteiger et al. analyzed registry data involving more than 240,000 total hip arthroplasty (THA) patients and found markedly lower revision rates in those who received XPLE rather than CPE acetabular components. At a mean follow-up of 16 years, the cumulative percentage of revisions was 6.2% in the XPLE group versus 11.7% in the CPE group. Among patients <55 years of age at the time of THA, at 7 years there was a five-fold increase in revision rates for procedures done with CPE compared to those done with XLPE.
Because the authors observed that the between-group differences in revision rates became more pronounced over time, it is possible that this difference will continue to grow as more data is gathered. When we consider the vast number of THAs performed around the world each year, this XLPE-related decrease in revision rate could have a beneficial impact on millions of patients.
The documented success so far of XPLE is a clear case where understanding the nature of the original problem (polyethylene wear) and applying consistent and innovative research to find a solution have allowed patients worldwide to reap the benefits associated with THA, with some assurance that their hip replacement may, in fact, last for their rest of their life.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
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
Linking Registry and Claims Data—Not as Boring as it Sounds
It is not often that The Journal of Bone & Joint Surgery publishes an article about data-linkage efforts. To even raise the topic with most readers of The Journal would elicit a yawn and quick dismissal of the abstract without a second thought. With this fact duly noted, the possibility of linking health-system joint-replacement registries with Medicare claims data is a first step in a potentially game-changing approach to achieving the long-term clinical research our specialty needs.
In the June 20, 2018 issue of JBJS, Raman et al. detail their successful linkage of a total ankle arthroplasty (TAA) registry with Medicare data without the use of unique patient identifiers. Among 280 TAA patients over the age of 65, 250 had their registry data linked with their Medicare record with exact matches for date of procedure, date of birth, and sex. Of the linked records, 214 (76.4%) had ≥3 years of postoperative claims data.
Why are these findings so important? The answer is follow-up. Every clinician and/or researcher who has attempted to follow patients beyond the first year after a procedure understands how difficult long-term follow-up is. We live in a mobile society in which informative posttreatment data is easily lost. The younger the patient group, the more difficult it usually is to locate patients as time passes. If patients are doing well, many stop coming to our offices, no matter how strongly we recommend annual follow-ups. Everyone is busy—including retirees—and most have better things to do than drive to their surgeon’s office or even complete a web-based questionnaire. Additionally, some patients care only about their own outcomes; they are not as focused as we are on contributing to the advancement of the profession and improving outcomes at the population level.
By linking patient data from a local health-system registry to nationwide claims data, we can gain a better understanding of long-term patient progress. We can use the patient- and implant-specific data housed in the registry and essentially substitute the information from follow-up visits that did not take place within the registry system with the data contained within the Medicare system, which follows beneficiaries wherever they live.
The marriage of registry and claims data is not perfect, though, because patients who are still working probably have private insurance coverage that is not captured by the Medicare system. (Of course, if universal coverage were to come to pass, that issue would be eliminated.) Furthermore, any time claims data are used, uncertainty about the accuracy of coding must be considered. These real-world limitations notwithstanding, the linkage of registry data with claims data does have great potential for enhancing our ability to analyze—and improve—long-term orthopaedic outcomes.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Orthopaedic Surgeons Hate Fixation Failures
Few things are more disheartening to an orthopaedic surgeon than taking a patient back into the operating suite to treat a failure of fixation. In part, that’s because we realize that the chances of obtaining stable fixation, especially in elderly patients with poor bone density, are diminished with the second attempt. We are additionally cognizant of the risks (again, most significant in the elderly) to cardiopulmonary function with a second procedure shortly after the initial one.
These concerns have led us historically to instruct patients to limit weight bearing for 4 to 6 weeks after hip-fracture surgery. On the other hand, we have seen evidence in cohort studies to suggest that instructing elderly patients with proximal femur fractures to bear weight “as tolerated” after surgery is safe and does not increase the risk of fixation failure.
In the June 6, 2018 issue of The Journal, Kammerlander et al. demonstrate that 16 cognitively unimpaired elderly patients with a proximal femur fracture were unable to limit postoperative weight bearing to ≤20 kg on their surgically treated limb—despite 5 training sessions with a physiotherapist focused on how to do so. In fact, during gait analysis, 69% of these elderly patients exceeded the specified load by more than twofold, as measured with insole force sensors. This inability to restrict weight bearing is probably related to balance and lower-extremity strength issues in older patients, but it may be challenging for people of any age to estimate and regulate how much weight they are placing on an injured lower limb.
With this and other recent evidence, we should instruct most elderly patients with these injuries to bear weight as comfort allows and prescribe correspondingly active physical therapy. As surgeons, we should focus our efforts on the quality and precision of fracture reduction and placement of surgical implants. This will lead to higher patient, family, and physical-therapist satisfaction and pave the way for a more active postoperative rehabilitation period and better longer-term outcomes.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Botox May Relieve Persistent Tennis Elbow
Lateral epicondylar tendinopathy (“tennis elbow”) that is refractory to the usual interventions of physical therapy/home-directed exercise, ice therapy, corticosteroid injections, and rest is a relatively common but very difficult clinical situation. Patients often become frustrated by the lack of improvement and want something to alleviate the pain and disability. However, the orthopaedic community has been reluctant to recommend surgical intervention except for the most severe cases because the outcomes of this surgery are not as predictable as we would like.
It is within this context that Creuzé et al., in the May 16, 2018 issue of The Journal, present results from a double-blind randomized trial elucidating the impact of low-dose Botulinum toxin injection on this chronic condition. Just over half of the patients treated with the Botulinum toxin injection (n = 29) had a >50% reduction in their initial pain intensity at day 90, and almost 20% felt completely cured. Those results were significantly better than those experienced by the group treated with placebo injections (n = 28).
Kudos to the industry sponsor of this study for supporting the double-blind design, because it removed a significant potential bias that might have otherwise tainted the results. The only fault I can find in the trial is a lack of reporting on the patients’ hand dominance and the magnitude of functional demand on their affected limbs. Before and after treatment, a patient who uses power tools with a dominant and affected limb during a physically demanding job may well have more severe symptoms than a person who works at a computer and whose dominant and affected limb is the “non-mouse” extremity.
It is rare indeed to find a study that blinds the administrator of an orthopaedic intervention, as injections and oral medications are not the most prominent tools in our predominantly surgical armamentarium. The inclusion criteria in the Creuzé et al. study reflected a realistic but difficult patient-enrollment scenario—a minimum of 6 months of symptoms (a mean of almost 19 months) despite previous attempts at all other well-known interventions. The fact that nearly all subjects in both groups had a previous steroid injection into the extensor carpi radialis brevis (ECRB) muscle and continued to experience symptoms confirms the difficulty of these cases and represents what many patients go through in search of an effective treatment.
Furthermore, the fact that only 50% of patients in the intervention group achieved significant pain relief reflects the refractory nature of this condition in many patients. These findings seem to indicate that surgical intervention will remain a necessary component of care for patients with lateral epicondylitis who are not cured by Botulinum toxin injection or other, more common treatment modalities—and that we should pay attention to improving surgical outcomes.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Innovation + Persistence: A Crucial Combination
In the 1970s and 80s, the debate regarding management of clubfoot deformity centered around the location of incisions and how aggressive to be with open releases of hindfoot joints. At that time, Prof. Ignacio Ponseti had been working on his conservative method of clubfoot correction for decades, but his technique was relegated to the sidelines and dismissed as being out of the main stream. Yet he persisted in carefully documenting his results, quietly perfecting his methods, and disseminating his technique by teaching other practitioners. Ever so slowly, the pediatric orthopaedic community migrated in his direction as the complications of the other aggressive surgical procedures, including stiff and painful feet, became apparent.
In the May 2, 2018 edition of The Journal, Zionts et al. report medium-term results from their center with Ponseti’s method. This is a very important study because most of the previously published data regarding mid- to long-term outcomes had come from Dr. Ponseti’s medical center.
The authors found that all 101 patients in the study treated with the Ponseti method had fair to good outcomes at a mean follow-up of 6.8 years. Nevertheless, >60% of the parents reported noncompliance with the bracing recommendations; almost 70% of patients had at least one relapse; and 38% of all patients eventually required an anterior tibial tendon transfer. Increased severity of the initial deformity, occurrence of a relapse, and a shorter duration of brace use were all associated with worse outcomes.
Taken as a whole, the results of this study are comparable to those presented by Ponseti and others from his institution. Even though the Zionts et al. investigation was also a single-center study, the findings are important considering the widespread use of his technique and limited “external” data confirming the validity of this method.
Dr. Ponseti created and refined a highly impactful technique that yields good outcomes in patients with a difficult problem. Although it took decades for his methods to be widely accepted, the lesson here is that what wins the day are careful documentation, thoughtful attention to how best to teach a method, and persistence in the face of skepticism.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Keeping a Clinical Eye on Downstream Costs
Medical economics has progressed to the point where musculoskeletal physicians and surgeons cannot ignore the financial implications of their decisions. Unfortunately, in most practice locations it is difficult, if not impossible, to ascertain the downstream costs to patients and insurers of our postsurgical orders for imaging, laboratory testing, and physical therapy (PT). In the April 18, 2018 issue of The Journal, Egol et al. present results from a well-designed and adequately powered randomized trial of outcomes after patients with minimally or nondisplaced radial head or neck fractures were referred either to outpatient PT or to a home exercise program focused on elbow motion.
At all follow-up time points (from 6 weeks to an average of 16.6 months), the authors found that patients receiving formal PT had DASH scores and time to clinical healing that were no better than the outcomes of those following the home exercise program. In fact, the study showed that after 6 weeks, patients following the home exercise program had a quicker improvement in DASH scores than those in the PT group.
The minor limitations with this study design (such as the potential for clinicians measuring elbow motion becoming aware of the treatment arm to which the patient was assigned) should not prevent us from implementing these findings immediately into practice. Each patient going to physical therapy in this scenario would have cost the healthcare system an estimated $800 to $2,400.
I wonder how many other pre- and postsurgical decisions that we routinely make would change if we had similar investigations into the value of ordering postoperative hemoglobin levels, surgical treatment of minimally displaced distal fibular fractures, routine postoperative radiographs for uncomplicated hand and wrist fractures, and PT after routine carpal tunnel release. These are just some of the reflexive decisions we make on a daily basis that probably have little to no value when it comes to patient outcomes. Whenever possible, we need to think about the downstream costs of such decisions and support the appropriate scientific evaluation of these commonly accepted, but possibly misguided, practices.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
During First Post-Op Month, Periprosthetic Fractures Are as Lethal as Native Hip Fractures
In 1922, Kellogg Speed, MD said in his American College of Surgeons address, “We enter the world under the brim of the pelvis and exit through the neck of the femur.” Since then, it has been repeatedly shown that femoral-neck and intertrochanteric hip fractures are associated with a high mortality rate during the first year following fracture. Now, in the era of widespread hip arthroplasty—and with the consequently increasing rates of periprosthetic fractures near the hip joint—it is relevant to ask whether periprosthetic fractures are associated with an increased risk of mortality similar to that seen after native hip fractures. In the April 4, 2018 issue of The Journal, Boylan et al. use the New York Statewide Planning and Research Cooperative System database to address that question.
The authors reviewed 8 years of native and periprosthetic hip fracture data to determine whether the 1-month, 6-month, and 12-month mortality risk between the two patient cohorts was similar. They found that the 1-month mortality risk in the two groups was similar (3.2% for periprosthetic fractures and 4.6% for native fractures). However, there were significant between-group differences in mortality risk at the 6-month (3.8% for periprosthetic vs 6.5% for native) and 12-month (9.7% vs 15.9%) time points.
This makes clinical sense because, in general, patients experiencing a native hip fracture have lower activity levels and general fitness and higher levels of comorbidity than patients who have received a total hip arthroplasty. Extensive research has resulted in protocols for lowering the risk of mortality associated with native hip fractures, such as surgery within 24 to 48 hours, optimizing medical management through geriatric consultation, and safer and more effective rehabilitation strategies. We need similar research to develop effective perioperative protocols for patients experiencing a periprosthetic fracture, as this study showed that 1 out of 10 of these patients does not survive the first year after sustaining such an injury. I also agree with the authors’ call for more research to identify patients with periprosthetic fractures who are “at risk of worse outcomes at the time of initial presentation to the hospital.”
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Giant-Cell Tumor Treatment: Curettage Without Denosumab Is Better
Denosumab is an FDA-approved drug for osteoporosis. It works by binding RANKL, thus inhibiting osteoclastic activity. Denosumab has also been shown to have a favorable impact on tumor response in relatively small, short-term studies among patients with giant-cell tumor of bone (GCTB).
In the March 21, 2018 issue of The Journal, Errani et al. report on a longer-term follow up (minimum 24 months, median 85.6 months) in two cohorts of patients with GCTB who were treated with joint-preserving curettage: those treated with curettage plus denosumab and those treated with curettage alone. The study found that denosumab administration was significantly associated with unfavorable outcomes in patients treated with curettage. Specifically, the local GCTB recurrence rate was nearly 4 times higher (60% vs 16%) in patients treated with denosumab plus curettage, compared to those treated with curettage alone.
Recent in vitro studies have shown that denosumab only slows giant-cell multiplication to some degree. The authors point out that patients treated with denosumab in this cohort study had more severe GCTB disease, which would seem to further confirm that cellular proliferation of giant cells is ineffectively slowed by this RANKL-binding drug. What’s most important about the Errani et al. study is that it’s the first one to look at the longer-term outcomes of denosumab usage before and after curettage for GCTB.
The authors emphasize that while their study shows a strong and independent association between denosumab administration and a high level of local recurrence, “causation could not be evaluated.” Still, at a time when clinicians, payers, and patients are critically evaluating every facet of treatment, it seems difficult to recommend the use of denosumab in addition to curettage for GCTB. The data in this study should encourage the musculoskeletal oncology community to continue to investigate other adjunctive treatments to be used with curettage for this disease process.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
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