Published 10/1/2017

Second Look – Clinical News and Views

These items originally appeared in AAOS Headline News Now, a thrice-weekly enewsletter 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).

Osteoporosis screening—
Findings published in Arthritis Care & Research (online) suggest that many rheumatoid arthritis (RA) patients for whom treatment is indicated may not receive osteoporosis medication. The research team followed 14,498 patients, 11,669 of whom had RA and 2,829 of whom had osteoarthritis (OA). At median 5.5-year follow-up, they found that among patients for whom treatment was recommended under 2010 American College of Radiology glucocorticoid-induced osteoporosis guidelines, approximately 55 percent reported use of osteoporosis medication. The research team noted that overall, RA patients were not more likely to undergo osteoporosis treatment and screening compared to OA patients. Factors associated with receipt of osteoporosis care in RA patients were older age, postmenopausal state, prior fragility fracture or diagnosis of osteoporosis, any duration of glucocorticoid treatment, and biologic use.

Open fracture—A study in the Journal of Orthopaedic Trauma (online) examines factors linked to health-related quality of life following open fracture. The researchers drew data on 1,427 open fracture patients from a prospective, randomized, controlled trial conducted in the United States, Canada, Australia, and India. They found that smoking, lower preinjury SF-12 Physical Component Score (PCS) and Mental Component Score (MCS), and work-related injuries were significantly associated with lower SF-12 PCS and MCS at 12-month follow-up. In addition, lower extremity fracture and a wound not closed at initial irrigation and débridement were significantly associated with lower 12-month SF-12 PCS but not MCS scores. The researchers note that only the adjusted mean difference for lower extremity fractures approached the minimally important difference for SF-12 PCS.

Bisphosphonates—A study in the Proceedings of the National Academy of Sciences (online) looks at mechanisms linked to atypical femur fractures (AFFs) among women treated with bisphosphonates. The authors biopsied proximal femoral cortical bone adjacent to the fracture site obtained from postmenopausal women during fracture repair surgery (n = 33) or total hip arthroplasty (THA) (n = 17). Using vibrational spectroscopy and nanoindentation, they found that tissue from bisphosphonate-treated women with atypical fractures was harder and more mineralized than that of bisphosphonate-treated women with typical osteoporotic fractures. Further, fracture mechanics measurements showed that tissue from patients treated with bisphosphonates had deficits in fracture toughness, with lower crack-initiation toughness and less crack deflection at osteonal boundaries than that of bisphosphonate-naïve patients. The authors write that the data suggest a deficit in intrinsic and extrinsic toughening mechanisms, which may contribute to AFFs in patients treated long-term with bisphosphonates.
Hip and knee
Cardiovascular disease—
Patients with hip or knee arthritis have a greater risk of cardiovascular events, and the risk increases with the number of hips and knees affected, according to a study in Osteoarthritis and Cartilage (online). The population-based cohort study involved 18,490 participants; of these, 24.4 percent had OA in the hip, knee, and/or hand. Over 13.4 years, 31.9 percent experienced a cardiovascular event. When all but walking limitation was controlled, a dose–response relationship was observed between number of joints affected by knee/hip OA and cardiovascular risk. The effect of hand OA was not significant. Self-reported difficulty walking was associated with a 30 percent increase in hazard for development of cardiovascular events. “These findings provide compelling evidence to suggest that hip/knee osteoarthritis-related walking difficulty is a clinically relevant and potentially modifiable risk factor for cardiovascular disease,” the authors write.

TXA alternative—A study involving patients undergoing primary joint arthroplasty at Durham Veterans Affair Medical Center (Durham, N.C.) suggests that use of epsilon aminocaproic acid (EACA) may yield reductions in hemoglobin loss and transfusion, positioning it as an alternative to tranexamic acid (TXA). The study, published in The Journal of Arthroplasty (online), involved 185 total knee and hip arthroplasty patients from the year before and 184 from the year after an EACA protocol was introduced. Hemoglobin loss and the incidence of blood transfusion were significantly lower in the EACA group compared to the control group. The authors note that EACA has been used sparingly in orthopaedic surgery but has a lower cost than TXA and a “favorable side effect profile.”

Electrotherapy and acupuncture—According to a study in JAMA Surgery (online), use of electrotherapy and acupuncture after total knee arthroplasty (TKA) may be associated with reduced and delayed opioid consumption. The research team conducted a meta-analysis of 39 randomized clinical trials covering 2,391 patients who were treated with nonpharmacologic interventions for postoperative pain management following TKA. They found that the most common interventions included continuous passive motion, preoperative exercise, cryotherapy, electrotherapy, and acupuncture. Of those, the research team notes that moderate-certainty evidence demonstrated that electrotherapy was linked to reduced use of opioids, while acupuncture was associated with delayed opioid use. Additionally, the research team states that low-certainty evidence linked acupuncture to reduced pain.

Shoulder and elbow
Shoulder septic arthritis—
A study in the Journal of the AAOS (August) compares outcomes among patients with shoulder septic arthritis who were treated with arthrocentesis, open irrigation and débridement, or arthroscopic irrigation and débridement. The authors reviewed data on 7,145 patients with native shoulder septic arthritis from the Nationwide Inpatient Sample database. Compared to patients who underwent surgical treatment, they found that patients treated nonsurgically had more medical comorbidities and complications, experienced longer length of stay, and were less likely to be discharged to home. Compared to patients treated with open surgery, patients who were treated arthroscopically had higher incidences of perioperative septicemia and urinary tract infection; similar average length of stay, hospital charges, and blood transfusion rates; and a lower incidence of osteomyelitis. Among patients with septicemia, the authors found that Staphylococcus aureus was the most frequently cultured causative organism.

TXA—According to data in the Journal of Shoulder and Elbow Surgery (August), patients who undergo primary reverse total shoulder arthroplasty (RTSA) may benefit from the use of TXA. The authors conducted a prospective, double-blind, randomized, controlled trial of 102 patients undergoing primary RTSA who received either intravenous TXA (n = 53) or placebo (n = 49). They found that total blood loss, total hemoglobin loss, and total drain output were less in the TXA cohort compared to the control cohort. The authors note that seven patients (14.3 percent) and 12 units of blood were transfused in the placebo group, while three patients (5.7 percent) and 3 units were transfused in the TXA group.

Displaced midshaft clavicle fracture—Data in The Journal of Bone & Joint Surgery (JBJS; Aug. 16) suggest that nonsurgical treatment may be associated with increased risk of nonunion compared to open reduction and internal fixation (ORIF) for patients with displaced midshaft clavicle fractures. The authors conducted a multicenter, randomized, controlled trial of 301 adult patients treated with either ORIF (n = 154) or nonsurgical management (n = 147). At 3-month follow-up, they found no significant difference in nonunion rate across cohorts. However, at 9-month follow-up, they noted a significantly higher nonunion rate among patients in the nonoperative cohort compared to the ORIF cohort.

Cholesterol and LDL—Findings in The American Journal of Sports Medicine (online) suggest that moderate and high preoperative total cholesterol and low-density lipoprotein (LDL) levels may be associated with increased risk of revision following primary arthroscopic rotator cuff repair. The authors conducted a retrospective, cohort study of 30,638 patients who underwent arthroscopic rotator cuff repair. Compared to patients with normal cholesterol or LDL levels (based on published standards), they found that the rate of revision rotator cuff surgery was significantly increased among patients who had moderate or high total cholesterol levels or moderate or high LDL levels (follow-up range: 6 months to 8 years). However, they found no significant difference in revision rates among patients with normal, moderate, or high triglyceride levels. In addition, among patients with high total cholesterol or high LDL levels, the authors noted that patients without statin use had significantly higher rates of revision surgery.

According to data in JBJS (Aug. 2), spine surgery among opioid-naïve patients may not be a major driver of long-term prescription opioid use. The authors reviewed data on 9,991 patients who underwent one of four common spinal surgical procedures (diskectomy, decompression, lumbar posterolateral arthrodesis, or lumbar interbody arthrodesis) and who had no history of opioid use in the 6 months prior to surgery. They found that 84 percent of patients filled at least one opioid prescription on discharge. At 30 days after discharge, 8 percent had continued opioid use; at 3 months, 1 percent continued use; and at 6 months, 0.1 percent continued use. The authors write that higher-intensity surgical procedures (posterolateral arthrodesis and interbody arthrodesis) and depression were associated with a decreased likelihood of discontinuing opioid use.

Gabapentinoids—Findings from a study in PLoS Medicine (online) suggest little evidence to support the use of gabapentinoids for the treatment of chronic low back pain (CLBP). The researchers conducted a systematic review and meta-analysis of eight randomized control trials that reported use of gabapentinoids (gabapentin and pregabalin) for the treatment of CLBP of less than 3 months duration among adult patients. In three studies that compared gabapentin against placebo (n = 185), they found that use of gabapentin was associated with minimal improvement of pain. The results of three studies that compared the use of pregabalin with other analgesics revealed that other analgesics provided greater improvement in pain. The researchers did not pool studies that examined pregabalin as an adjuvant, but note that the largest study showed no benefit of adding pregabalin to tapentadol. In addition, they found that use of gabapentin increased the likelihood of dizziness, fatigue, difficulties with mentation, and visual disturbances compared with placebo, although GRADE evidence quality was found to be very low for dizziness and fatigue, low for difficulties with mentation, and moderate for visual disturbances. The researchers identify a need for large high-quality trials to more definitively inform this issue.

Revision cervical spine surgery—Findings published in Spine (online) suggest that a majority of patients may benefit from revision cervical spine surgery. The researchers reviewed prospectively collected data on 115 patients who underwent cervical revision surgery for recurrent disease (n = 21), pseudarthrosis (n = 45), and adjacent segment disease (n = 49). At 12-month follow-up, they found significant improvement in all patient-reported outcomes regardless of etiology. The researchers write that satisfaction was met in 75.5 percent to 85.7 percent of patients, depending on the etiology of the revision need, with complication rates of 4 percent to 9 percent.

Osteoid osteoma—
A study published in the Journal of Pediatrics (online) suggests that osteoid osteoma in children and young adults may be safely and effectively treated using magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU). The researchers compared two groups of patients who had radiologically confirmed, symptomatic osteoid osteoma. The first group comprised 7 males and 2 females aged 6 to 16 years treated with MR-HIFU. The second group comprised 8 males and 1 female aged 6 to 10 years treated with radiofrequency ablation. The researchers found that clinical response to treatment, evaluated in terms of analgesic requirement, visual analog scale pain score, and sleep quality, was comparable between the groups. They conclude that MR-HIFU treatment of osteoid osteoma refractory to medical therapy is feasible and can be performed safely in pediatric patients, without any incisions or exposure to ionizing radiation.

Patient safety
Myocardial ischemia—
A study in HSS Journal (online) examines rates of myocardial ischemia following orthopaedic surgery. The authors reviewed data on 10,627 inpatient orthopaedic procedures performed at a single center and identified 805 patients as at risk for postoperative myocardial ischemia. Of those patients, they found that 20.6 percent (166 of 805) of the patients had elevated serum cTnI levels (defined as cTnI >0.02 ng/mL), while 1.2 percent had documented postoperative myocardial infarction (10 of 805). Among at-risk TKA, THA, or posterior spinal fusion (PSF) patients, 19 percent (102 of 532) had elevated cTnI levels and 31 percent (32 of 102) had postoperative cardiac complications. After adjustment for sex, age, body mass index, cardiac risk factors, and medications (statins and ß-blockers), the authors note that PSF patients were significantly more likely to experience myocardial injury compared to TKA and THA patients.

Continued opioid use—Two recent studies examine factors linked to continued opioid use. The first, in The Journal of Pain (online), reviewed data on 1,353,902 persons aged 14 years and older with no history of cancer or substance abuse and found that the probability of continued opioid use at 1 year was 5.3 percent. Across all pain etiologies, the authors found that chronic pain; inpatient admission; prescribed doses of ≥ 90 morphine milligram equivalents, initiated with tramadol or long-acting opioids; and increased days’ supply of first prescription were consistently associated with a lower likelihood of opioid discontinuation.

In the second study—a research letter published in JAMA Surgery (online), researchers reviewed information on 117,118 patients who met criteria for sustained prescription opioid use. They found that only 800 individuals (0.7 percent) received their initial opioid prescription following an inpatient encounter and 458 (0.4 percent) had undergone an inpatient procedure.