AAOS Now

Published 5/1/2017

Second Look – Clinical News and Views

These items originally appeared in AAOS Headline News Now, a thrice-weekly e-newsletter that keeps AAOS members up to date on clinical, socioeconomic, and political issues, with links to more detailed information. Subscribe at www.aaos.org/news/news.asp (member login required).

Knee
Home-based rehabilitation—Findings published in The Journal of the American Medical Association (March 14) suggest that a monitored, home-based rehabilitation program may be as effective as inpatient rehabilitation for patients who undergo uncomplicated total knee arthroplasty (TKA). The authors conducted a randomized trial of 165 patients who underwent inpatient hospital rehabilitation and home-based rehabilitation (n = 81) or home-based rehabilitation alone (n = 84), and 87 nonrandomized patients enrolled in an observation group, which included only the home-based program. At 26-week follow-up, the authors found no significant difference between the three cohorts in a 6-minute walk test, Oxford Knee Score, or EuroQol Group 5-Dimension Self-Report Questionnaire.

Patient-specific instrumentation—Data in The Journal of Bone and Joint Surgery (JBJS; March 15) suggest that use of patient-specific instrumentation (PSI) in TKA may improve the accuracy of femoral component alignment and global mechanical alignment, but increase risk of outliers for tibial component alignment. The research team conducted a meta-analysis of 44 studies covering 2,866 knees that underwent surgery using PSI and 2,956 knees that underwent surgery with standard instrumentation. For PSI compared to standard instrumentation, the pooled relative risk (RR) of mechanical axis malalignment was 0.79, the pooled RR of femoral coronal-plane malalignment was 0.74, and the pooled RR of tibial sagittal plane malalignment was 1.32. PSI was also associated with minor reductions in total surgical time and blood loss.

Hip
Mortality risk—According to a study in the Journal of Internal Medicine (online), hip fracture may be associated with increased risk of all-cause mortality in both the short and longer term. The authors reviewed information on 122,808 participants from eight cohorts in Europe and the United States. At mean 12.6-year follow-up, there were 4,273 incident hip fractures and 27,999 deaths. After adjustment, they found that hip fracture was positively associated with increased all-cause mortality during the first year, but also through 8 or more years. The association was stronger among men than women, although the difference was not significant.

Total hip arthroplasty instability—According to data from a study published in The Journal of Arthroplasty (online) and presented at the AAOS Annual Meeting, patients with spinal deformity who undergo total hip arthroplasty may be at increased risk of total hip arthroplasty (THA) instability, despite having an acetabular cup position generally considered within acceptable alignment. The researchers used standing stereoradiography to evaluate spinopelvic parameters, acetabular cup anteversion, and inclination of 139 THAs among 107 patients with sagittal spinal deformity. They found that the rate of THA dislocation was 8.0 percent, with a revision rate of 5.8 percent for instability. Overall, patients who sustained dislocations had significantly higher spinopelvic tilt, T1 pelvic angle, and mismatch of lumbar lordosis and pelvic incidence. Among all patients, 78 percent had safe anteversion while supine, which decreased to 58 percent when standing due to increases in spinopelvic tilt. Among patients with dislocated THAs, the researchers found that 80 percent had safe anteversion, 80 percent had safe inclination, and 60 percent had both parameters within the safe zone.

DAIR—Findings in The Journal of Arthroplasty (online) suggest that débridement, antibiotics, irrigation, and implant retention (DAIR) may be an option for treatment of hip periprosthetic joint infection (PJI) in certain patients, especially during the early postoperative period. The authors reviewed data on 122 DAIRs performed over a 16-year period. Overall, 67 percent of DAIRs were of primary arthroplasties, and 60 percent were performed within 6 weeks of the index arthroplasty. They found that infection eradication was achieved in 104 cases (85 percent) using a single or multiple DAIR approach, and 10-year implant survivorship was 77 percent. In 32 cases, more than one DAIR was required. "Early PJI and exchanging modular components at DAIR were independent factors for a fourfold increased infection eradication and improved long-term implant survival," the authors write. They also caution that DAIR is associated with increased morbidity, and a risk of further surgery and instability.

TXA—A study published in JBJS (March 1) suggests that oral and intravenous formulations of tranexamic acid (TXA) may offer equivalent reductions in blood loss for patients who undergo primary THA. The authors conducted a randomized, double-blind trial of 83 primary THA patients who received either 1.95 g of TXA orally 2 hours preoperatively (n = 40) or a 1-g TXA intravenous bolus in the operating room prior to incision (n = 43). They found that the mean reduction of hemoglobin was similar between oral and intravenous groups, and the mean total blood loss was equivalent between oral and intravenous administration. Overall, three patients (7.5 percent) in the oral group and one patient (2.3 percent) in the intravenous group were transfused, but the difference was not significant. No patients in either group experienced a thromboembolic event. The authors conclude that oral TXA may offer efficacy similar to that of intravenous TXA, at a greatly reduced cost.

Alendronate—Findings published in The Journal of Arthroplasty (online) suggest that early administration of alendronate may help prevent bone loss in the calcar region following THA. The research team conducted a prospective study of 60 consecutive patients with hip osteoarthritis who had undergone primary cementless THA and who were randomly assigned to receive alendronate (n = 20) or alfacalcidol (n = 18), or serve as controls (n = 22). The researchers found that all groups showed a significant decrease in bone mineral density (BMD) of the calcar at current follow-up compared to values at both 1 week and 1 year postoperatively. The research team noted that, at most recent follow-up, BMD values were significantly higher in the alendronate group than in the alfacalcidol and control groups.

Shoulder
Postoperative pain—A study in The American Journal of Sports Medicine (AJSM; April) examines the relationship between rotator cuff tear area and postoperative pain in patients who undergo arthroscopic rotator cuff repair. The researchers reviewed information on 1,624 patients who underwent arthroscopic rotator cuff repair, and found that intraoperative rotator cuff tear areas did not correlate with pain scores preoperatively or at 1 week following surgery. However, they noted that a smaller tear area was associated with more frequent and severe pain during overhead activities, at rest, and during sleep, as well as a poorer perceived overall shoulder condition at 6-week, 3-month, and 6-month follow-up. Overall, patients who were younger, had partial-thickness tears, and had occupational injuries experienced more pain postoperatively. The researchers noted that the re-tear rate was 7 percent in tears smaller than 2 cm2, but reached 44 percent in tears larger than 8 cm2.

Transosseous technique—Data published in AJSM (online) suggest that postoperative pain may decrease more quickly after transosseous hardware-free suture repair compared to single-row anchor fixation for rotator cuff repair. The authors conducted a randomized controlled trial of 69 patients with rotator cuff tear, 35 of whom were treated with metal anchors and 34 of whom were treated with standardized transosseous repair. They found no significant difference between the two arthroscopic repair techniques in terms of functional and radiologic results. However, patients in the transosseous cohort had significantly less pain, especially from postoperative day 15.

Foot and ankle
Wound complication—A study in Foot & Ankle International (online) examines factors that may be linked with increased risk of wound complication following total ankle arthroplasty (TAA). The researchers reviewed prospectively collected data on 762 consecutive primary TAAs. They found that 26 patients (3.4 percent) had a total of 49 surgical procedures to treat major wound issues. Compared to patients in the control group, the researchers noted that patients with major wounds had a significantly longer mean surgery time and trended toward a longer median tourniquet time. Overall, patients without wound complications were more likely to have posttraumatic arthritis, whereas those with wound complications were more likely to have primary osteoarthritis.

Fracture
Reoperation factors—According to Scientific Paper 197, presented at the 2017 AAOS Annual Meeting, lower extremity fractures, Gustilo-Anderson type III fractures, and moderate to severe wound contamination may be associated with an increased risk of reoperation in patients with open fractures. The researchers reviewed data on 2,447 patients with open extremity fractures from the Fluid Lavage of Open Wounds (FLOW) study and found that 323 participants required reoperation. They noted that risk of reoperation was also greater in patients whose initial surgery was performed 6 hours or longer after injury. However, patients who received a surgical preparation solution in the emergency department and those who received an iodine-based preparation solution in the operating room were at reduced risk of reoperation.

NSAIDs and healing—Results of a prospective randomized controlled trial suggest that NSAID use may not impair long-bone fracture healing in pediatric patients, and may be a useful alternative for pain control in the acute fracture setting. Researchers randomized 81 skeletally immature patients with a long-bone fracture to receive either acetaminophen (control) or ibuprofen (NSAID) for postfracture management. At 6-month follow-up of 78 patients, the researchers found no statistically significant differences in pain scores between the groups at any time point. Study findings were presented in Scientific Poster P262 at the AAOS Annual Meeting.

Multimodal analgesics—A study in JBJS (March 15) suggests that surgical site injection with a multimodal analgesic cocktail may reduce pain and opioid use following surgical management of femoral fracture. The authors conducted a prospective randomized controlled trial of 102 patients who underwent surgical intervention for a broad range of femoral fracture patterns and who received either an intraoperative, surgical-site injection into the superficial and deep tissues containing ropivacaine, epinephrine, and morphine, or no injection. Compared to controls, they found that the injection group demonstrated significantly lower visual analog scale scores in the recovery room and at the 4-, 8-, and 12-hour postoperative time points. In addition, the authors noted that opioid consumption was significantly lower in the injection group compared to the control group over the first 8 hours following surgery. They observed no cardiac or central nervous system toxicity secondary to infiltration of the local anesthetic.

Osteoporotic fracture—A report from the US National Center for Health Statistics offers Fracture Risk Assessment Tool (FRAX)-based estimates of 10-year probability of hip and major osteoporotic fracture among adults aged 40 years and older in the United States during 2013-2014. The authors used US version 3.05 of the FRAX algorithm to calculate fracture probability based on measured risk factors such as femur neck bone mineral density, height, and weight, or self-reported factors such as fracture history, glucocorticoid use, rheumatoid arthritis, smoking, and alcohol intake. Among adults aged 40 years and older, they found that the mean skew-adjusted fracture probabilities were 0.5 percent for hip fracture and 5.3 percent for major osteoporotic fracture; for adults aged 50 years and older, the probabilities were 0.9 percent and 7.4 percent, respectively. The percentages of adults aged 50 years and older with an elevated hip or major osteoporotic fracture probability (defined as 3 percent or greater for hip fracture and 20 percent or greater for major osteoporotic fracture) were 19 percent and 8 percent, respectively.

Pelvic embolization—Findings published in the Journal of Orthopaedic Trauma (April) suggest that pelvic embolization may not be associated with increased risk of infection for patients who undergo open treatment of acetabular fracture. The research team reviewed information on 72 patients with acetabular fracture, 25 of whom underwent embolization, 16 of whom underwent angiography without embolization, and 31 of whom did not undergo angiography. Among patients in the embolization cohort, they found that infection developed in two patients (8 percent), whereas infection developed in five patients (31 percent) in the nonembolization cohort. Among patients who did not undergo angiography, the deep infection rate was 9.6 percent, compared to 4 percent following embolization. "This suggests that concerns for higher rates of infection are not substantiated," the research team writes, "and pelvic embolization should be performed when indicated."

Arthritis
Arthritis report—A report released by the US Centers for Disease Control and Prevention (CDC) projects that approximately 23 percent of adults in the United States have some form of arthritis. In addition, almost 60 percent of adults with arthritis are women, and almost 60 percent of people with arthritis are of working age. The report offers recommendations for care of arthritis, including several aimed at healthcare providers, including:

  • Urge patients with arthritis to be physically active and to strive for a healthier weight to ease joint pain.
  • Recommend patients attend proven educational programs about managing their condition.
  • Ask patients about any depression or anxiety, and offer care, treatment, and links to services.
  • Consult the guidelines of the American College of Rheumatology or other professional organizations for treatment options, including medicines.

Patient safety
Implant sonicate culture—Data from a study in Clinical Orthopaedics and Related Research (online) suggest that routine use of implant sonicate cultures in arthroplasty revision cases may help confirm the presence of bacteria in both clinical and occult infections. The research team performed implant sonicate fluid cultures on surgically removed implants from 503 revision THAs and TKAs. Of those, infection was definitively identified in 178 implants (35 percent), based on Musculoskeletal Infection Society criteria, whereas 325 (65 percent) were deemed free from infection. The research team found that specificity of implant sonicate culture was not significantly different from that of synovial fluid culture or tissue culture, but sensitivity of implant sonicate culture was 97 percent, compared to 57 percent for synovial fluid culture and 70 percent for tissue culture.

Opioid dependence—A report from the US Centers for Disease Control and Prevention (CDC) states that the likelihood of a patient becoming dependent on opioids begins to increase after the third day supplied and rises rapidly thereafter. The writers note that CDC guidelines call for treatment of acute pain with opioids to be for the shortest duration possible. "Prescribing <7 days (ideally £3 days) of medication when initiating opioids could mitigate the chances of unintentional chronic use," they write. "when initiating opioids, caution should be exercised when prescribing ³1 week of opioids or when authorizing a refill or a second opioid prescription because these actions approximately double the chances of use 1 year later. in addition, prescribers should discuss the long-term plan for pain management with patients for whom they are prescribing either schedule ii long-acting opioids or tramadol.">

Physical activity—Findings from a study in The Journal of Bone and Mineral Research (online) suggest that a lack of physical activity may reduce bone strength in adolescents. The research team used high-resolution peripheral quantitative computed tomography (HR-pQCT) to evaluate 209 participants aged 9 to 20 years at baseline. They conducted a maximum of four annual measurements at the tibia (n = 785 observations) and radius (n = 582 observations). The research team found that moderate to vigorous physical activity was a positive independent predictor of bone strength and bone volume fraction at the tibia and radius, of total area and cortical porosity at the tibia, and a negative predictor of load-to-strength ratio at the radius.