Has Conventional Polyethylene Become Obsolete in THA?
Highly cross-linked polyethylene (XLPE) has been in clinical use for nearly 15 years. In acetabular components for total hip arthroplasty (THA), XLPE’s superior wear characteristics and lower revision rates, relative to conventional polyethylene (PE), have been demonstrated in numerous studies. Here is one more: a 10-year Level I study in the October 18, 2017 issue of The Journal of Bone & Joint Surgery by Devane et al.
In this double-blinded, randomized trial, authors measured 2-D, 3-D, and volumetric wear (in mm or mm2), along with wear rates (mm/year), presence or absence of osteolysis, and revision rates in 91 patients at specified time intervals, up to a minimum of 10 years. The following results corroborate the general findings from most other studies on this topic:
- The mean 3-D wear rate among patients with the XLPE acetabular liner was 0.03 mm/yr, versus 0.27 mm/yr among patients with conventional PE.
- Eight percent of patients in the XLPE group showed radiographic evidence of osteolysis, versus 38% of patients in the PE group.
- Patients with the conventional PE liner had a significantly higher revision rate (14.6%) than those with the XLPE liner (1.9%).
There were no significant between-group differences in clinical outcome scores, including the Oxford Hip Score and SF-12 physical well-being score.
The authors note that “the longer-term implications of these findings are unclear,” but their calculations indicated that, through 20 years, none of the XLPE liners would wear through, but 6 of the conventional PE liners would require revision due to wear-through.
Long-term Results Show No Advantage to “Minimalist” THA
The debate regarding minimally invasive/minimal incision total hip arthroplasty (THA) has been simmering for a decade and a half. When assessing the impact of adult reconstruction procedures, patients and treating physicians alike are most interested in longer-term results. Improved return of function in the first 3 to 6 weeks is of some value to all patients—and perhaps of great value to younger patients—and that has been one of the purported advantages of the “minimalist” approach. But it is the long-term results that really matter.
In the October 18, 2017 issue of The Journal, Stevenson et al. provide 10-year results from a 2005 randomized trial of small-incision posterior hip arthroplasty, and they confirm it adds no clinical, radiographic, or implant-survivorship benefit when compared with a standard posterior approach. An extra caveat here is that these procedures, originally done in 2003-2004, were undertaken by a highly experienced surgeon who had performed >300 minimal-incision THAs. In the hands of surgeons with less experience, smaller incisions may result in suboptimal component positioning and other complications, a point emphasized by Stevenson et al. and by Daniel Berry in his JBJS editorial accompanying the original study.
This long-term data is of great value to patients and surgeons alike. It is my hope that such high-quality evidence will temper the claims used in marketing materials that hype minimally invasive approaches, to which hip surgeons are routinely subjected.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
More Efficient Orthopaedic Education Needed
The October 4, 2017 issue of JBJS contains another in a series of “What’s Important” personal essays from orthopaedic clinicians. This “What’s Important” article comes from Drs. Peter Scoles and Shepard Hurwitz.
The authors suggest that integration of medical school curricula with the first year of postgraduate training is a practical approach to improving efficiency and reducing costs to both doctors in training and the academic medical centers that help train them. In explaining specific ways to change the paradigm for training orthopaedic surgeons, the authors conclude that an integrative approach would accelerate the process for qualified candidates, while lowering costs and ensuring adequate training opportunities for all.
If you would like JBJS to consider your “What’s Important” story for publication, please submit a manuscript via Editorial Manager. When asked to select an article type, please choose Orthopaedic Forum and include “What’s Important:” at the beginning of the title.
Because they are personal in nature, “What’s Important” submissions will not be subject to the usual stringent JBJS peer-review process. Instead, they will be reviewed by the Editor-in-Chief, who will correspond with the author if revisions are necessary and make the final decision regarding acceptance.
With OCA, Don’t Fret About Condyle Matching
Osteochondral allograft transplantations (OCAs) are becoming a mainstay of treatment for knee-cartilage injuries. To help ensure that the allograft plug is transplanted with <1 mm of step-off from the surrounding recipient cartilage, many surgeons restrict themselves to orthotopic OCAs—matching the graft-recipient condyles in a lateral-to-lateral or medial-to-medial fashion.
However, in the October 4, 2017 issue of The Journal of Bone & Joint Surgery, Wang et al. demonstrated that both orthotopic and non-orthotopic (e.g., lateral condyle-to-medial condyle) OCA resulted in significantly improved outcomes in 77 cases followed for a mean of 4.3 years. The authors found that reoperation rates and pre- and postoperative scores in physical functioning and pain did not differ significantly between the orthotopic (n=50) and non-orthotopic (n=27) groups. These results suggest that condyle-specific matching may not be necessary.
One problem with orthotopic OCA is that 75% of the available allograft is supplied in the form of lateral condyles, while most full-thickness cartilage lesions presenting for treatment occur in the medial condyle. Consequently, surgeon preferences for orthotopic OCA limit the number of available matches and lead to an estimated 13% of available grafts being discarded.
Noting that many factors contribute to successful resurfacing of cartilage defects in the knee, the authors say that “it may be overly simplistic to assume that a conventionally matched orthotopic allograft will ensure a smooth surface contour at the recipient site.” They go on to conclude that “if surgeons forewent condyle-specific matching, more allografts would be readily available, which would shorten wait times, provide fresher grafts with increased chondrocyte viability, and lower procedure costs.”
Aggressive Treatment Improves QOL in Many Cases of Spinal Metastases
A significant portion of metastatic disease comes with no clear identification of a primary tumor; this is unfortunately the case with many spinal metastases. In the October 4, 2017 issue of The Journal, Ma et al. evaluate the survival and patient-reported quality-of-life (QOL) outcomes for patients with spinal metastases from cancer of unknown primary origin.
Their prospective longitudinal study confirms that a more aggressive strategy that combines surgery and radiation therapy results in better QOL (as measured with the four-domain FACT-G instrument) than radiation alone. There was no significant difference in survival time between the two groups. In a subgroup analysis of patients receiving surgery, those who underwent circumferential decompression had significantly better functional and physical well-being and higher total QOL scores than those who underwent decompressive laminectomy.
These findings emphasize the critical role of shared decision making in such difficult situations. A dire diagnosis with poor statistical chances of long-term survival does not mean that patients should not be informed of treatment options and have the opportunity to opt for an aggressive surgical approach, especially if that decision is likely to result in improved QOL. Let us endeavor to compassionately provide patients with the facts, as we understand them, and let them select from among the medical and surgical options that are at their disposal. More often than not, in this sad scenario, it seems aggressive is better in terms of quality of life.
Faster Relief for Patients with Painful Bone Metastases
A technique that combines magnetic resonance (MR) imaging with high-intensity focused ultrasound hyperthermia provides faster pain relief than conventional radiation therapy (RT) for patients with a painful bone metastasis.
In the September 20, 2017 issue of JBJS, Lee et al. report on a matched-pair study of 63 patients with a painful bone metastasis who received either magnetic resonance-guided focused ultrasound (MRgFUS) or RT as first-line treatment. Both modalities were effective overall, yielding response rates of >70% at the three-month follow-up evaluation. However, MRgFUS was more efficient, providing a 71% response rate at 1 week after treatment, compared with 26% for RT at that same time point.
The total treatment time and cost of the two modalities were similar, and neither was associated with adverse events above grade 2. Among MRgFUS patients, there was a 14% rate of positioning-related pain and a 33% rate of sonication-related pain, which typically resolved within 1 day after treatment.
Lee et al. report that the median overall survival of patients in the study was 12.7 months in the MRgFUS group and 9.8 months in the RT group, a statistically nonsignificant difference. But the authors emphasize that the study was more about pain relief than extending life. “Reduc[ing] pain, restor[ing] function, and maintain[ing] quality of life is imperative” for those with bone metastasis, the authors conclude. They also caution that MRgFUS is not appropriate for bone metastases of the skull or most of the spine, or for any lesion that is not at least 1 cm away from “tissues at risk.”
Webinar—Helping Clinically Excellent Colleagues Who Have Challenging Behaviors
Sometimes the most talented, skilled physicians with whom you work are also prone to displaying challenging behaviors. Often, these physicians are not cognizant of how their colleagues perceive them, so how can you—as the supervisor, friend, and/or peer of such clinicians—help ensure that patients continue to benefit from their clinical and surgical gifts without behavioral difficulties diminishing their contributions?
On Thursday, October 26, 2017 at 8:00 pm EDT, the American Orthopaedic Association (AOA) and The Journal of Bone & Joint Surgery (JBJS) will host a complimentary webinar that will deliver practical and effective methods you can use to help physicians who are clinically outstanding, but behaviorally difficult, start to make remedial changes.
The presentations about how to be helpful to such colleagues will be led by:
- Gerald Hickson, senior VP for Quality, Safety, and Risk Prevention at Vanderbilt University Medical Center
- William Hopkinson, professor of orthopaedic surgery at Loyola Medicine
- George Russell, professor and chair of orthopaedic traumatology at the University of Mississippi Medical Center
Moderated by Dr. Douglas Lundy, orthopaedic trauma surgeon at Resurgens Orthopaedics, this webinar will include a 15-minute live Q&A session during which attendees can ask questions of the panelists.
Seats are limited, so register now!
TEA Proves Durable in Elderly Patients with Distal Humeral Fractures
Several studies have demonstrated good short- and intermediate-term outcomes with total elbow arthroplasty (TEA) to treat acute distal humeral fractures. Now, in the September 20, 2017 issue of The Journal of Bone & Joint Surgery, Barco et al. provide data confirming that TEA provides durable pain relief and motion improvements over a minimum of 10 years, albeit with a number of major complications.
Among 44 TEAs performed in elderly patients with and without inflammatory arthritis whom the authors followed for ≥10 years, the mean Mayo Elbow Performance Score was 90.5 points. Five elbows (11%) developed deep infection that required surgical treatment. The revision-free survival rates for elbows with rheumatoid arthritis were 85% at 5 years and 76% at 10 years, while survival rates for elbows without rheumatoid arthritis were 92% at both time points. That difference was not statistically significant, although men in the study were much more likely to experience a revision than women. Twenty-five of the 44 patients died during the long-term follow-up, but the majority of those had their implant in place.
While reporting on these promising long-term revision-free survival rates, Barco et al. emphasize that complications were “frequent and diverse in nature…and have required a reoperation, including implant revision, in 12 of 44 patients.” So, while the good news is that a majority of patients in this situation will die with a useful joint and sound implant, the authors conclude that “surgeons treating this kind of injury should follow their patients over time and should be prepared to manage a wide array of complications using complex techniques.”
After Achilles Repair, Musculotendinous Strength Remains a Big Challenge
Amid ongoing uncertainty regarding the optimum management of Achilles tendon ruptures, recent controlled trials seem to have moved the pendulum back toward nonsurgical treatment. Still, there are many people walking around on surgically repaired Achilles tendons, and in the September 20, 2017 issue of The Journal, Heikkinen et al. report on the 13+-year outcomes of operative repair followed by early functional postoperative management in 52 patients.
All orthopaedic surgeons who have treated patients with this tendon injury have noted the postoperative calf atrophy. Using carefully analyzed MRI studies, these authors found that the mean volumes of the soleus, medial gastrocnemius, and lateral gastrocnemius muscles were 13%, 13%, and 11% lower, respectively, in the affected legs than in the uninjured legs. The mean 6% elongation of the repaired tendon that Heikkinen et al. also found at this long-term follow-up makes sense, because we are repairing tendinous tissue whose inherent collagen bundle structure has been “overstretched” prior to total failure. It also makes sense that surgeons are often hesitant to shorten the ends of the tendon aggressively for fear of placing too great a tensile strain on the suture repair.
What is most impressive to me is the degree of calf-muscle atrophy revealed in these results. Whether the findings from future trials tilt us further toward nonoperative or back toward operative care, we need to solve the muscle atrophy issue. The solution will most likely come from even more aggressive rehabilitation. To date, many of us have erred on the side of not pushing these patients too far during rehab, out of concern for failure of repair or reinjury.
With solid surgical and nonsurgical treatments for fractures, we have solved many issues to achieve optimum bone healing with good anatomic and strength outcomes. However, we have not really begun to make gains on limiting muscle, ligament, and tendon atrophy in lower extremity injuries. This should be high on the agenda for the trauma research community during the next 2 to 3 decades.
Marc Swiontkowski, MD
JBJS Editor-in-Chief
Fewer In-Hospital Complications with TAA vs Ankle Fusion
Among the many variables discussed when patients and surgeons make a decision between ankle arthrodesis (fusion) and total ankle replacement (TAA) for end-stage ankle arthritis, in-hospital complication rate is an often-overlooked point of comparison, partly due to a dearth of good data.
In the September 6, 2017 edition of The Journal of Bone & Joint Surgery, Odum et al. report findings from a matched cohort study that compared these two ankle procedures in terms of minor and major perioperative complications. To make more of an apples-to-apples comparison, the authors statistically matched 1,574 patients who underwent a TAA with an equal number of those who underwent fusion.
A major in-hospital complication (such as a pulmonary embolism or mechanical hardware problem) occurred in 8.5% of fusion patients and in 5.3% of TAA patients. After adjusting for case mix, Odum et al. found that ankle arthrodesis was 1.8 times more likely than TAA to be followed by a major complication. Regarding minor in-hospital complications (such as venous thrombosis or hematoma/seroma), the authors found a 29% lower risk of complications among arthrodesis patients compared to TAA patients, although that difference was not statistically significant (p = 0.14). Regardless of surgical procedure, patient age ≤67 years and the presence of multiple comorbidities were independently associated with a higher risk of a major complication.
A possible explanation for the lower in-hospital major-complication rate in TAA patients, say the authors, is that “TAA is more likely to be performed in younger, healthier patients with better bone quality and smaller deformities.”
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