ACL and meniscal injuries increase the risk of primary total knee replacement for osteoarthritis: a matched case–control study using the Clinical Practice Research Datalink (CPRD)
Khan T, Alvand A, Prieto-Alhambra D, Culliford DJ, Judge A, Jackson WF, Scammell BE, Arden NK, & Price AJ. Br J Sports Med. 2017; Online Ahead of Print December 21, 2017.
Take Home Message: A patient with a knee injury is more likely to get a knee replacement and be younger when getting it than someone without a history of injury.
A knee injury, such as an anterior cruciate ligament (ACL) injury or meniscal injury, is a major risk factor for the early development of knee osteoarthritis within 10 to 20 years after injury. However, it remains unknown if a patient with a history of knee injury is likely to progress to end-state OA, which often requires a total knee replacement (TKR). These authors used a case-control study to investigate the chance of having a TKR surgery within 20 years among patients with a history of ACL or meniscal injury compared to healthy controls. The authors identified patients who received a primary TKR between 1991 to 2011 from a United Kingdom clinical practice database. They then matched those patients with a TKR to two controls by age, gender, and same practice (about 50,000 cases and 100,000 controls). A person with a history of an ACL injury was ~7 times more likely to receive a TKR than someone without an ACL injury. Someone with a meniscal injury was ~15 times more likely to have a TKR than a person without a meniscal injury history. A patient with an ACL and meniscal injury was 4 times more likely to receive a TKR compared with someone with an isolated ACL injury. Patients with an ACL injury were also ~13 years younger at the time of TKR than patients with no history of injury.
This large-scale case-control study demonstrates that ACL or meniscal injuries are linked to a higher risk of knee OA that results in needing TKR at much younger ages than those without a knee injury. These findings confirm previous research about higher knee OA risks within 10 years of an injury. Patients with an ACL and meniscal injury were 4 times more likely to undergo TKR in comparison to patients with an isolated ACL injury. The authors identified that they were unable to compare surgical to non-surgical management of knee injuries. Claes and colleagues estimated that a person with an ACL injury and meniscectomy were 3.5 times more likely to have osteoarthritis at 10 years after an injury than people who had an isolated ACL injury or an ACL injury with meniscal repair. Hence, it would be interesting to see which patients were handled surgically versus non-surgically and which surgery was performed. ACL reconstruction fails to protect against OA, as supported by the findings presented in a previous Sports Med Res post on the work by Luc and colleagues, and may possibly increase OA risk as a second macro-traumatic event. The longer-term problem is that the number of ACL and meniscal knee injuries are increasing, which will have major implications to the number of people who will get an OA diagnoses and a potential TKR. As clinicians and researchers, we need to determine what we can do to help relieve the impending burden on the health care system. For example, we should take steps to implement injury prevention programs and re-evaluate how we manage knee injuries, with a focus on not just short-term benefits but also long-term benefits.
Questions for Discussion: Are you currently incorporating any long-term secondary prevention strategies with knee injury patients? What is the advice that you give patients who have suffered a knee injury to help prolong their knee health?