What’s New in Adult Reconstructive Knee Surgery

Abstract

Nonoperative Management of Osteoarthritis of the Knee As surgical treatment advances, patients with knee osteoarthritis may exhibit increasing pessimism toward the nonsurgical interventions of muscle strengthening and weight loss, countered by unrealistic expectations of arthroplasty1. Orthopaedic surgeons should keep this in mind to enhance patient outcomes. Physical Therapy Physical therapy for knee osteoarthritis can be effective either in a controlled outpatient setting or in a home-based setting2. The guidance of a physical therapist in home-based exercise was shown to lead to greater improvement in range of motion, pain, and muscle strength compared with home exercise not led by a physiotherapist3. In a different study, individualized physical therapy was demonstrated to be cost-effective when compared with usual medical care4. In a cohort of 206 patients in a prospective randomized controlled trial (RCT), the exercise physical therapy group had improved Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores (−28.2 [95% confidence interval (CI), −49.2 to −7.1]) compared with controls4. Risk and Health Policy One recent study found that patients scheduled for primary total knee arthroplasty (TKA) would gamble a 20% risk of death, give up 27% of a 10-year life span, or pay 23% of their income for perfect results from primary TKA5. This underscores patients’ desire for successful TKA and the health system’s responsibility for properly administrating delivery. Using data from the National Surgical Quality Improvement Program (NSQIP) registry, the authors of 1 recent study found that length of stay for patients undergoing TKA decreased from 3.7 days for the period of 2006 to 2009, to 3.0 days for 2014 to 20166. Following the bundled-payment program implementation for primary TKA, patient discharge to inpatient rehabilitation units decreased by 59% relative to baseline. This has unfortunately led to an unintended consequence of a further need for assistive care and a 28% decrease in recovered motor gains7. Furthermore, if patients are discharged to home, it may be critical for a subset to receive home-health-based therapy. The authors of 1 recent study found that, when compared with patients with ≤5 in-home health-care physical therapy sessions, patients with ≥14 visits had a 50% greater improvement in activities of daily living (p < 0.0001)8. Operative Management: Non-Arthroplasty Options Kaplan-Meier survivorship of high tibial osteotomy for symptomatic osteoarthritis in varus knees was demonstrated to be 55% at 15 years, with increased risk of failure found for female sex (hazard ratio [HR], 2.37; 95% CI, 1.06 to 5.33; p = 0.04) and age (HR, 1.07 for each additional year of life; 95% CI, 1.03 to 1.11; p = 0.001)9. Injection of mesenchymal stem cells at the time of high tibial osteotomy may improve the amount and durability of articular cartilage at clinical follow-up10. Unicondylar Knee Arthroplasty Outcomes and Design The authors of a recent meta-analysis found that the survivorship of unicondylar knee arthroplasty in a general population was 95.3% at 5 years and 91.3% at 10 years11. An NSQIP database review of 8,029 patients indicated that obese patients may not be at increased risk of 30-day complications following unicompartmental knee arthroplasty12. However, in recent retrospective and prospective studies, 10-year all-cause survivorship of prostheses was 87.5% to 88.1%13,14 for patients classified as obese, demonstrating clinical failure rates greater than those of nonobese counterparts13. Cementless Unicondylar Knee Arthroplasty A retrospective review of 1,000 Oxford cementless unicondylar knee replacements15 for standard indications16 documented survivorship free of revision of 96.8% at a mean of 10 years. A report using data from the Finnish Arthroplasty Register showed Kaplan-Meier survivorship of 93.7% at 3 years and 92.3% at 5 years for 1,076 cementless Oxford unicondylar knee arthroplasti