Published 4/1/2019

Second Look - Clinical

Hip and knee

Combined ACL and ALL reconstruction—A retrospective analysis published in Arthroscopy (online) found that professional athletes who underwent combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction had good postoperative outcomes. Researchers queried the Scientific Anterior Cruciate Ligament Network International Study Group database for patients undergoing primary combined ACL and ALL reconstruction between January 2011 and March 2016; 70 patients (mean age, 23.2 years; 68.6 percent male) were included in the final analysis. Side-to-side anteroposterior laxity difference went from 7.1 mm preoperatively to 0.4 mm postoperatively. Prior to surgery, 22.8 percent of patients had grade I pivot shift, whereas 32.9 percent had grade II, and 44.3 percent had grade III; postoperatively, 94.3 percent of patients had no pivot shift, and the remaining 5.7 percent had grade I. Most patients (85.7 percent) returned to professional sports within one year of surgery. Preoperative mean subjective International Knee Documentation Committee (IKDC), Lysholm, and Tegner scores improved after surgery, from 56.1 to 90.5, 48.4 to 94.4, and 9.3 to 8.8, respectively. Preoperatively, all patients had an objective IKDC grade C (55.7 percent) or grade D (44.3 percent); after surgery, nearly all patients (92.9 percent) had grade A, and the remaining 7.1 percent had grade B. There were 11 subsequent ipsilateral reoperations.

Prolonged TJA operative time and infection risk—Total joint arthroplasty (TJA) patients with prolonged operative times may have a greater likelihood of postoperative surgical site infections (SSIs) and periprosthetic joint infections (PJIs), according to a retrospective study published in The Journal of Arthroplasty (online). A total of 17,342 patients underwent primary unilateral unilateral total knee arthroplasty (TKA) or total hip arthroplasty (THA) at a single institution between 2005 and 2016 and had a minimum one-year follow-up. The total 90-day SSI rate was 1.2 percent, and the one-year PJI rate was 0.8 percent. Patients whose surgeries took longer than 90 minutes were nearly twice as likely to sustain an SSI or PJI (2.1 percent and 1.4 percent, respectively) than those whose operative times were between 60 and 90 minutes (1.1 percent and 0.7 percent, respectively) and 60 minutes or shorter (0.9 percent and 0.7 percent, respectively). Multivariate analysis found that each 20-minute increase in operative time increased 90-day SSI risk by an odds ratio (OR) of 1.346 and one-year PJI risk by an OR of 1.253.

Acetaminophen plus ibuprofen after THA—THA patients may have significantly reduced 24-hour postoperative morphine consumption when treated with acetaminophen plus ibuprofen compared to acetaminophen alone but not ibuprofen alone, according to a randomized, controlled trial published in JAMA (online). A total of 556 patients completed the trial. The acetaminophen plus ibuprofen group had a mean 24-hour morphine consumption of 20 mg compared to 36 mg for the acetaminophen alone group, 26 mg for the ibuprofen alone group, and 28 mg for the half-strength acetaminophen plus ibuprofen group. The median difference in morphine consumption between the acetaminophen plus ibuprofen group versus the acetaminophen alone group was 16 mg. Additional between-group differences in morphine consumption were 10 mg for the acetaminophen alone group versus the ibuprofen alone group, 8 mg for the acetaminophen alone group versus the half-strength acetaminophen plus ibuprofen group, 6 mg for the acetaminophen plus ibuprofen group versus the ibuprofen alone group, and 2 mg for the ibuprofen alone group versus the half-strength acetaminophen plus ibuprofen group.

Lifespan of knee implant—A systematic review published in The Lancet (online) determined how long a patient can expect a knee implant to last. Researchers queried MEDLINE and Embase for relevant case series and cohort studies published through July 21, 2018. Eligible articles reported 15-year or longer survival of primary total knee replacement (TKR) and unicondylar knee replacement (UKR) in patients with osteoarthritis. National joint replacement registry reports were also reviewed and assessed separately. Thirty eligible articles spanning 33 case series provided data on all-cause survival for 6,490 TKRs (26 case series) and 742 UKRs (seven case series). There were no available case series for 25-year TKR survival. Australian and Finnish registry data provided 47 series spanning 299,291 TKRs and five series reporting on 7,714 UKRs. UKR 25-year estimated survival was 72 percent, per the database data; 25-year TKR and UKR survival rates were 82.3 percent and 69.8 percent, respectively, per the registry data. The researchers believe the registry data are more accurate.

Malnutrition and TJA complications—A systematic review published in The Journal of Arthroplasty (online) found that serologic malnutrition may be associated with postoperative complications in TJA patients. Researchers reviewed 20 studies pertaining to the effects of malnutrition in THA and TKA patients. They observed a strong correlation between preoperative serologic malnutrition markers and inferior postoperative outcomes. All 20 studies evaluated albumin as a malnutrition marker; 11 (55 percent) used total lymphocyte count as a marker, and six (30 percent) used transferrin. Eighteen studies (90 percent) associated at least one serological marker with worse outcomes after TJA. Albumin levels less than 3.5 dg/L were indicative of postoperative wound complications.

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).