Why is differential diagnosis of anterior knee pain important? Because the brain thinks it is

It can be difficult for the clinician to differentially diagnose, and identify the key nociceptive contribution to, anterior knee pain (AKP). The most commonly involved structures in non-traumatic presentations of knee pain are the patellofemoral joint and patellar tendon. Wasting of the quadriceps and/or impaired motor control are seen in the clinical presentation of both conditions but it is not known if these clinically similar conditions have comparable corticospinal control of the quadriceps. Current approaches for managing AKP would be improved with a better understanding of the local and central contributors to pain and dysfunction. Treatment directed solely at local contributors have had variable results, with exercise based therapy directed towards the quadriceps the most effective rehabilitation. An understanding of the corticospinal control of the quadricepsmayimprove treatment outcomes and demonstrate the similarities or differences in various AKP presentations. This presentation will present data demonstrating that there are differences in the cortical control of the quadriceps (excitability and inhibition) in patellar tendinopathy compared with other AKP presentations and provide a clinically relevant toolkit for differential diagnosis of anterior knee pain. The clinical implications of these findings in terms of both the differential diagnosis and considerations for rehabilitation will be discussed.