News in 10

The 10 items below are the most significant elements of recent editions of Headline News Now—the AAOS thrice-weekly, online update of news of interest to orthopaedic surgeons. Check this page regularly for updates.
Updated on May 21, 2013.

1. FDA announces Class 1 recall for Stryker Orthopaedics ShapeMatch Cutting Guide.
The U.S. Food and Drug Administration (FDA) has announced a Class 1 recall for the Stryker Orthopaedics ShapeMatch Cutting Guide, due to software defects that may result in the production of incorrect cutting guides. In January 2013, FDA issued a Product Notification to all branches, agencies, surgeons, and risk managers at affected hospitals, informing them of the problem and risk mitigation factors. On April 10, 2013, Stryker issued an Urgent Medical Device Recall. ShapeMatch Cutting Guides have not been available on the market since November 2012. The manufacturer is recommending that patients who had knee replacement surgery in which ShapeMatch Cutting Guides were used and who are experiencing symptoms should contact their surgeon. If symptom-free, the patient should continue to follow-up with the surgeon as scheduled.
Read more...

AAOS has issued a Patient Safety Member Alert regarding this issue. Read the alert…(member login required)

For additional information, please contact Yin Becker, Stryker Corporation, at 201-831-5000 or:yin.becker@stryker.com

2. Study: Edge-loading most important predictor of wear rate in large-diameter MoM hips.
A study published in the April 17 issue of the Journal of Bone & Joint Surgery suggests that edge-loading may be the most important predictor of wear rate in large-diameter metal-on-metal (MoM) hip replacements. The authors prospectively recorded preoperative, intraoperative, and postoperative data on 138 hips and analyzed 276 components retrieved from failed MoM hip devices. They found that the most important factor responsible for variation in wear rate was the presence or absence of edge-loading, even when adjusted for cup inclination angle. In addition, they noted strong positive correlations between acetabular cup and femoral head wear rates and between wear rates and both blood cobalt and chromium ion levels.
Read the abstract…

3. Study: Intracompartmental pressure monitoring may offer high sensitivity for predicting acute compartment syndrome.
According to the authors of a study published in the April 17 issue of the Journal of Bone & Joint Surgery, continuous intracompartmental pressure monitoring should be considered for patients at risk for acute compartment syndrome. The authors analyzed prospective data on 850 patients who had sustained a tibial diaphyseal fracture over a 10-year period. Overall, 152 patients underwent fasciotomy for the treatment of acute compartment syndrome: 141 had acute compartment syndrome (true positives), 6 did not have it (false positives), and 5 underwent fasciotomy despite having a normal differential pressure reading, with subsequent operative findings consistent with acute compartment syndrome (false negatives). At mean 59-week follow-up, of 698 patients who did not undergo fasciotomy, 689 had no evidence of any late sequelae of acute compartment syndrome (true negatives). The estimated sensitivity of intracompartmental pressure monitoring for suspected acute compartment syndrome was 94 percent, with an estimated specificity of 98 percent, an estimated positive predictive value of 93 percent, and an estimated negative predictive value of 99 percent.
Read the abstract...

4. Study: Specializing in one sport may increase risk of stress fractures and other injuries in young athletes.
According to preliminary findings presented at the annual meeting of the American Medical Society for Sports Medicine, young athletes who specialize in one sport and train intensively may have a significantly higher risk of stress fractures and other severe overuse injuries, compared with those who play a variety of sports. The research team enrolled 1,206 athletes between the ages of 8 years to 18 years who had requested sports physicals or obtained treatment at two centers between 2010 and 2013. Overall, there were 859 total injuries, including 564 overuse injuries, in cases in which the clinical diagnosis was recorded. The researchers found that specializing in a single sport increased the risk of overall injury, even when controlling for an athlete’s age and hours per week of sports activity. In addition, they found that study participants were more likely to be injured if they spent more than twice as much time playing organized sports as they spent in unorganized free play.
Read more...

5. Study: Achilles tears seen most in male weekend warriors.
A study of U.S. patients published in the April issue of Foot & Ankle International reports that tears of the Achilles tendon occur most commonly in male athletes and that playing basketball accounts for 32 percent of all ruptures. Sports were responsible for 68 percent of the ruptures overall and for 77 percent ruptures in patients younger than age 55; the average age of injured patient was 46 years. The association with sports was higher than that seen in European studies (in which soccer was the most commonly implicated sport) and those of U.S. military patients. Older patients and those with a body mass index (BMI) greater than 30 were more likely to have injuries from non-sports causes, and injuries in these patients were more likely to delayed or missed, with negative implications for eventual outcomes. "Older individuals, and those with a higher BMI, should be evaluated carefully if they have lower leg pain or swelling in the Achilles tendon region,” lead author Steven M. Raikin, MD, commented in Medical NewsToday.
Read more...
Read the study ...

6. Physician compensation report finds orthopaedists on top.
A report on physician compensation issued by Medscape finds that physician income is increasing in almost every specialty, reversing a decline in compensation during the past several years. At an average of $405,000 per year, orthopaedics is listed as the highest compensated specialty. However, the report notes a high level of dissatisfaction, finding that only 37 percent of orthopaedists would choose medicine again as a career, and only 21 percent would choose the same practice setting. Overall, eight specialties earned a mean of at least $300,000 during 2012, and primary care physicians also posted gains.
Read more...
View the orthopaedic section of the report…(registration may be required)
View the overall report…

7. Study: Knee arthroplasty associated with increased likelihood of weight gain.
A study published in the May issue of the journal Arthritis Care & Research finds that patients who undergo knee arthroplasty may be at an increased risk of clinically important weight gain following surgery. The researchers compared data on 917 patients in the Mayo Clinic arthroplasty registry against 237 controls from the population-based Rochester Epidemiology Project, and found that 30 percent of patients in the knee arthroplasty sample had gained 5 percent or more of their baseline weight at 5-year follow-up, compared to 19.7 percent of the control sample. Additional arthroplasty procedures during the follow-up period further increased risk for weight gain, relative to the control sample. Important risk factors for weight gain among arthroplasty patients were age of less than 60 years and weight loss during the 5-year preoperative period.
Read more...(registration may be required)
Read the abstract…

8. Study: Interspinous spacers linked with fewer complications, but greater revision rates, compared with decompression or fusion.
Findings published in the May 1 issue of the journal Spine suggest that, compared with decompression or fusion, interspinous distraction procedures may be associated with fewer complications for the index operation, but higher rates of revision surgery. The researchers conducted a retrospective cohort analysis of Medicare claims data on 99,084 patients with spinal stenosis who underwent surgery, and found that patients who received spacers were older than those undergoing decompression or fusion, but had little evidence of greater comorbidity. Overall, patients who received a spacer alone had fewer major medical complications than those undergoing decompression or fusion surgery, but had higher rates of further inpatient lumbar surgery at 2-year follow-up. The associations persisted after adjustment for patient age, sex, comorbidity score, and previous hospitalization.
Read more...
Read the abstract…

9. Study: Outcomes similar whether arthroplasty patients engage in preoperative exercise or not.
Findings presented at the annual meeting of the Osteoarthritis Research Society International suggest that preoperative neuromuscular exercise does not significantly improve function or pain 3 months after total hip or knee arthroplasty. The researchers conducted a randomized, controlled trial of 165 patients with severe symptomatic hip or knee osteoarthritis and who were scheduled for unilateral primary total joint replacement to either receive a brochure recommending exercise prior to surgery and a 3-hour information session with health professionals, or the same intervention plus individualized group-based neuromuscular exercise guided by a physiotherapist. At 3 months postoperative, the research team found that self-reported activities of daily living were similar across both groups. However, patients in the exercise group improved immediately following exercise, and that improvement carried over to 6 weeks after surgery, indicating an earlier onset of recovery.
Read more...

10.  Study: Double-row construct may reduce failure in Achilles tendon repair, compared to single row.
According to a study published online in the American Journal of Sports Medicine (AJSM), double row construct for reinsertion of a completely detached Achilles tendon using proximal and distal rows may result in significantly larger contact area initially and significantly higher peak load to failure. The researchers conducted a controlled laboratory study of 18 cadaver Achilles tendons that were split longitudinally and detached, exposing the calcaneus. The team performed ostectomy on each tendon using either 2 suture anchors (single row) or a 4-anchor (double row) construct. They found that the double-row refixation technique was statistically superior to the single-row technique in footprint area measurement initially and 5 minutes after repair. In addition, the double-row construct demonstrated significantly improved measures for peak load, load at yield, and slope. No significant difference between constructs were found with regard to cyclic loading.
Read the abstract…