Patients who have undergone non-arthroplasty operative procedures are at higher risk to require total knee arthroplasty: commentary on the article by Robert H. Brophy, MD, et al.: "total knee arthroplasty after previous knee surgery: expected interval and the effect on patient age".

Abstract

Commentary Just as the entire field of medicine has witnessed a major evolution in the past several decades, so has orthopaedic surgery. Concomitant with this increase of knowledge has been an increased sophistication on the part of our patients. An increasing number of individuals participate in sporting activities in early childhood, leading to an increase in the number of weekend warriors during adolescence and early adulthood. This has led to an increasing number of injuries and the resulting need for orthopaedic intervention. As noted by Brophy et al., more than 650,000 knee arthroscopies and 175,000 anterior cruciate ligament reconstructions are performed annually in the United States. The long-term outcome of these procedures has received little attention. It is essentially unknown whether these patients will be at an equal or increased risk for developing further disease in their knee and ultimately require total knee arthroplasty. The purpose of this study was to attempt to address this specific question. Brophy and colleagues determined the prevalence of previous knee surgery in patients undergoing total knee arthroplasty and attempted to determine the interval from the previous surgery to the ultimate total knee arthroplasty. The authors also wished to assess the age at which the patients who had previous knee surgery presented for total knee arthroplasty. Brophy and colleagues questioned if these patients were actually younger than the overall patient population presenting for total knee arthroplasty. The authors reviewed the prospective total joint arthroplasty registry from their institution from 1998 to 2010. They identified 1372 patients from the registry and, of these, 1286 had a diagnosis of osteoarthritis or posttraumatic arthritis. Twenty-nine percent of the patients had a history of knee surgery, with arthroscopy as the most common type of surgery. The authors found that a greater percentage of men had had previous knee surgery when compared with women and that patients with a history of knee surgery were younger than patients without a history of knee surgery. Interestingly, although the average time from previous meniscectomy to total knee arthroplasty was 12.6 years, 14% of patients underwent total knee arthroplasty within one year after meniscectomy. Brophy and colleagues also noted that the average interval from ligamentous reconstruction to total knee arthroplasty was 21.8 years, which was significantly longer than the interval from meniscectomy to total knee arthroplasty. The implications from this study are interesting and perhaps, as the authors note, concerning. Both men and women have increased their sports-related activity, with women having a greater increase. Therefore, there is an associated increase in sports-related injury and a concomitant increase in non-arthroplasty knee reconstructive surgery. This will result in an increasing number of younger patients receiving total knee arthroplasties, which will, in turn, yield an increasing number of knee revisions. Certainly, all of these factors will place an increasing economic burden on our health-care system. Of concern is the 14% of patients who underwent total knee arthroplasty within one year after meniscectomy. Clearly, older patients with moderate osteoarthritis and degenerative meniscal tears do not fare well with arthroscopic meniscectomy. This is a clear take-home message from this article. This article does have several limitations. The patient population extends from 1998 to 2010. Some of the procedures performed in the late 1990s and early 2000s are not being utilized today. The data on previous operations were collected by asking the patients and, therefore, may be subject to recall bias. Improved surgical procedures and enhanced documentation may have an effect on the timing of total knee arthroplasty. Despite these limitations, this study clearly shows that patients who have had prior knee surgery will present for total knee arthroplasty at a younger age. This is especially true for men, while women have a shortened interval from the time of surgery to total knee arthroplasty. As orthopaedic surgeons, we must be prepared to treat these patients. Future studies should focus on how previous knee surgery affects the outcomes of total knee arthroplasty.