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AAOS Now

Published 1/1/2016

Second Look—Clinical News and Views

Hip
Hip fracture repair—
Findings from a study conducted in Canada and published in the Dec. 2 issue of The Journal of Bone & Joint Surgery suggest that use of an intramedullary device (IM) for the management of intertrochanteric fracture may be associated with improved radiographic outcomes, but not improved functional outcomes. The prospective, randomized, multicenter study involved 167 patients aged 55 years or older who sustained an isolated AO/OTA Type-A2 intertrochanteric fracture and who were treated with either an IM device (n = 87) or a traditional extramedullary hip screw (n = 80). At 12-month follow-up, no significant differences between cohorts were found in either primary or secondary clinical outcomes. However, radiographic parameters favored the IM cohort, which displayed less femoral neck shortening.

Hip pain and OA—Data from a study published online in The BMJ suggest that hip pain and radiographic osteoarthritis (OA) may not correlate in some patients. An assessment of pelvic radiographs for hip OA among two cohorts—the Framingham Osteoarthritis Study (n = 946) and the Osteoarthritis Initiative (n = 4,366)—found the following:

  • In the Framingham study, 15.6 percent of hips in patients with frequent hip pain displayed radiographic evidence of hip OA, while 20.7 percent of hips with radiographic hip OA were frequently painful.
  • In the Osteoarthritis Initiative study, 9.1 percent of hips in patients with frequent pain displayed radiographic hip OA, and 23.8 percent of hips with radiographic hip OA were frequently painful.

Hip pain was not present in many hips with radiographic OA, and many painful hips did not show radiographic hip OA. Thus, the evidence suggests that in many cases, hip OA might be missed if diagnosticians rely solely on hip radiographs.

Infections
Postoperative C. difficile
A study published online in JAMA Surgery examined factors associated with postoperative Clostridium difficile infection (CDI). The retrospective, observational study covered 468,386 surgical procedures from the Veterans Affairs Surgical Quality Improvement Program database and the Decision Support System pharmacy database. The postoperative CDI rate was 0.4 percent per year and varied by surgical specialty.

Overall, 30-day CDI rates were higher in complex and emergency procedures, and in contaminated or infected wounds. Patients with postoperative CDI were significantly older, more frequently hospitalized after surgery, had longer preoperative hospital stays, and had received three or more classes of antibiotics.

Surgical site infections—According to a study published online in Foot & Ankle International, topical application of vancomycin powder in the surgical wound may help reduce risk of surgical site infection (SSI) for high-risk diabetic patients who undergo foot and ankle surgery. The retrospective, case control study involved 162 patients with diabetes mellitus who underwent reconstructive surgery of the foot or ankle, 81 of whom received topically applied vancomycin and 81 matched patients who did not. The use of topically applied vancomycin was associated with a 73 percent reduction in likelihood of SSI. Overall, the rate of superficial infection was not significantly different between cohorts. However, compared to the control cohort, deep infection was 80 percent less likely among patients in the vancomycin cohort.

Joints
Impact of body changes—
Two studies presented at the annual meeting of the Radiological Society of North America look at the effect of body changes on joint cartilage. An investigation into different degrees of weight loss and the progression of knee cartilage degeneration found that patients with >10 percent weight loss displayed significantly reduced cartilage deterioration as measured via magnetic resonance imaging (MRI).

A study using continuous, mobile MRI surveillance of cartilage integrity of 44 runners participating in a transcontinental ultramarathon found that, with the exception of the patellar joint, nearly all cartilage segments showed a significant initial mean T2 signal increase within the first 1500 km run. There was an unexpected secondary T2 decrease in ankle and hindfoot joints, indicating the ability of the cartilage matrix in ankle and hindfoot joints to regenerate under ongoing running burden.

Complications after arthroplasty—Findings from a study published online in The Journal of Arthroplasty suggest that patients may be at increased risk of complication after hip and knee arthroplasty at a safety net hospital compared to the same procedure performed at a university medical center. The retrospective review examined 533 consecutive hip and knee arthroplasties performed by a single experienced surgeon at a safety-net hospital and a university center. At minimum 2-year follow-up, 8 percent of patients in the safety net group had a revision, compared to 20.5 percent of patients at the university hospital. However, the rate of adverse outcomes (total complications, deep infections, and reoperations) was significantly higher in the safety net cohort.

Knee
According to data from a study conducted in Korea and published in Arthroscopy, microfracture (MFX) and adipose-derived stem cells (ADSCs) with fibrin glue may offer improved outcomes compared to MFX alone for patients with symptomatic knee cartilage defects. The prospective, randomized study involved 80 patients aged 18 to 50 years who had a single International Cartilage Repair Society grade III/IV symptomatic cartilage defect (≥3 cm2) on the femoral condyle. At mean 24.3-month follow-up, 65 percent (n = 26) of patients in the ADSC cohort had complete cartilage coverage of the lesion, compared to 45 percent (n = 18) of patients in the control cohort. In addition, at mean clinical follow-up of 27.4 months, the ADSC group had significantly greater improvement in mean Knee Injury and Osteoarthritis Outcome Score pain and symptom subscores. However, no significant difference between groups regarding improvements in other subscores (activities of daily living, sports and recreation, and quality of life) were noted.

Pediatric orthopaedics
Pediatric spine—
Data from a study published in Neurosurgery suggest that pediatric lumbar disk herniation may be associated with structural malformations of the lumbar spine. The research team reviewed anteroposterior radiographs of 63 consecutive pediatric patients with lumbar disk herniation at a single center. High intercrestal lines and long L5 transverse processes were associated with a significantly higher incidence of L4/L5 disk herniation, whereas low intercrestal line and lumbarization were associated with L5/S1 disk herniation. The patients' visual analog scale scores, pain frequency, and Oswestry Disability Index scores all improved significantly after surgery.

Child abuse—Data from a study conducted in the United Kingdom and published in the Emergency Medicine Journal suggest that pediatric injuries due to suspected child abuse may be identified based on demographic pattern. Of 14,845 pediatric patients from The Trauma Audit and Research Network database, 13,708 patients had accidental injuries, 368 were victims of alleged assault, and 769 patients were victims of suspected child abuse. Nearly all (97.7 percent) trauma cases due to suspected child abuse occurred in children aged 5 years or younger, with 76.3 percent in infants aged 1 year or younger. Compared with patients who had accidental injuries, suspected victims of abuse had higher overall injury severity scores, higher proportion of head injury, and a threefold higher mortality rate.

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.