The effect of arthroscopic surgery of the knee on hospital utilization.

Arthroscopic surgery of the knee has reduced in-hospital utilization of 37 percent for surgical treatment of internal derangements of the knee at The Mount Sinai Medical Center. In a study comparing arthrotomies of the knee in 1974 (N = 106) to arthroscopic surgery of the knee in 1984 (N = 221) it was found that while the average patient's age increased 4.39 years to 38.79 years (p less than 0.01) and the number of nonligament knee surgeries increased 108 percent, total annual inpatient hospital days fell to 459 in 1984, from 733 in 1974. The average length of stay in 1984 decreased to 2.07 days, from 6.91 days in 1974 (p less than 0.001). Ambulatory patients comprised 16 percent of the total in 1984, and there were none in 1974. New surgical techniques are reducing in-hospital usage and revenues. Due to the greater third-party reimbursement rate for outpatient operating room use as compared to per diem hospital reimbursement, efficient utilization of ambulatory operating rooms can help to compensate for decreased inpatient census.