What’s New in Adult Reconstructive Knee Surgery
Every month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of all OrthoBuzz Specialty Update summaries.
This month, Gwo-Chin Lee, MD, author of the January 18, 2017 Specialty Update on Adult Reconstructive Knee Surgery, selected the five most clinically compelling findings from among the more than 100 studies summarized in the Specialty Update.
Nonoperative Knee OA Treatment
—Weight loss is one popular nonoperative recommendation for treating symptoms of knee osteoarthritis (OA). An analysis of data from the Osteoarthritis Initiative found that delayed progression of cartilage degeneration, as revealed on MRI and clinical symptoms, positively correlated with BMI reductions >10% over 48 months.1
Total Knee Arthroplasty
—In total knee arthroplasty (TKA), the drive toward producing normal anatomy has led to explorations of alternative alignment paradigms. A prospective randomized study found that small deviations from the traditional mechanical axis (known as kinematic alignment) can be well tolerated and do not lead to decreased survivorship or poorer functional outcomes at short-term follow up.2
—Controversy exists about the optimal method to achieve stemmed implant fixation in revision TKA. A randomized controlled trial of TKA patients with mild to moderate tibial bone loss found no difference in tibial implant micromotion between cemented and hybrid press-fit stem designs, based on radiostereometric analysis.
Blood Management in TKA
—Minimizing blood loss and transfusions is crucial to minimizing complications after TKA. A randomized, double-blind, placebo-controlled trial found that intra-articular and intravenous administration of tranexamic acid (TXA) was more effective than intravenous TXA alone, without an increased risk of venous thromboembolism (VTE). However, the optimal regimen for TXA remains undefined.
—VTE prophylaxis is essential for all patients undergoing TKA. A risk-stratification study of pulmonary embolism (PE) after elective total joint arthroplasty reported that the incidence of PE within 30 days after either hip or knee replacement was 0.5%. Risk factors associated with PE were age of > 70 years, female sex, and higher BMI. The presence of anemia was protective against PE. The authors developed an easy-to-use scoring system to determine risk for VTE to help guide chemical prophylaxis.3
- Gersing AS, Solka M, Joseph GB, Schwaiger BJ, Heilmeier U, Feuerriegel G, Nevitt MC, McCulloch CE,Link TM. Progression of cartilage degeneration and clinical symptoms in obese and overweight individuals is dependent on the amount of weight loss: 48-month data from the Osteoarthritis Initiative. Osteoarthritis Cartilage. 2016 Jul;24(7):1126-34. Epub 2016 Jan 30.
- Calliess T, Bauer K, Stukenborg-Colsman C, Windhagen H, Budde S, Ettinger M. PSI kinematic versus non-PSI mechanical alignment in total knee arthroplasty: a prospective, randomized study. Knee Surg Sports Traumatol Arthrosc. 2016 Apr 27. [Epub ahead of print]
- Bohl DD, Maltenfort MG, Huang R, Parvizi J, Lieberman JR, Della Valle CJ. Development and validation of a risk stratification system for pulmonary embolism after elective primary total joint arthroplasty. J Arthroplasty. 2016 Sep;31(9)(Suppl):187-91. Epub 2016 Mar 17.