Incidence of Manipulation Under Anesthesia or Lysis of Adhesions After Arthroscopic Knee Surgery

Arthrofibrosis after knee arthroscopy is a challenging complication. Previous studies reporting incidences of manipulation under anesthesia (MUA) or lysis of adhesions (LOA) after knee arthroscopy are limited by confounders such as small sample size and regional sampling bias.To investigate the incidence of MUA or LOA after common arthroscopic knee procedures.Descriptive epidemiology study.A national insurance database was retrospectively queried for arthroscopic knee procedures from 2007 to 2011. The incidence of postoperative MUA and LOA within 3 and 6 months postoperatively was determined for each of 13 common arthroscopic knee surgeries, including ligamentous reconstructive procedures, cartilage restoration procedures, and meniscal procedures.A total of 330,714 unique patients who underwent knee arthroscopy were included in the study. The overall incidence of MUA was 0.06% to 6.00% by 3 months and 0.11% to 8.00% by 6 months postoperatively. The incidence of LOA was somewhat less, ranging from 0.04% to 4.00% by 3 months and 0.06% to 6.00% by 6 months postoperatively. Isolated arthroscopic partial meniscectomy had the lowest incidence of postoperative MUA and LOA, while multiligament reconstructions and meniscal transplants had the highest incidences.The overall incidence of MUA and LOA after arthroscopic knee procedures is low but rises significantly as the number of concomitant procedures or complexity of the procedures increases. This information may be useful in counseling patients on the likelihood of MUA or LOA based on the type of arthroscopic knee procedure that is planned.