Anterior knee pain, or pain localized to the front of the knee, is a common knee complaint. Anterior knee pain presents a challenge in diagnosis and treatment for the orthopedic physician. Anterior knee pain can be caused by several pathologic conditions including tendonitis, cartilage damage or wear and patellar (kneecap) malalignment or instability. A careful history and physical examination along with diagnostic testing are important factors in determining the correct diagnosis and treatment for anterior knee pain.
History should try to differentiate between knee complaints related to pain versus instability. Patients typically report pain over the front of the knee; pain may occur at rest or in association with activities such as stair climbing, squatting or kneeling. Onset of pain may occur acutely following traumatic injury or may present as a result of a change in routine or activity level such as embarking on a new or different exercise program. Physical examination focuses on limb alignment, the presence of tenderness over tendons and ligaments surrounding the patella, assessment of muscular tightness and imbalance and evaluation of patellar tracking. Plain radiographs (X-rays) are useful to determine presence of arthritic changes in the patellofemoral joint and assess presence of patellar tilt or extremity malalignment. On occasion additional diagnostic testing such as MRI or CT scans may be helpful in assessing articular cartilage or patellofemoral alignment.
The mainstay of treatment for anterior knee pain is nonsurgical. Studies have shown that a period of rest, quadriceps strengthening exercises, stretching and anti-inflammatory medication have been highly successful in producing relief. Bracing has been used with success in patients with symptomatic patellar instability. Surgery is usually not necessary for most patients with anterior knee pain. For some patients with cartilage damage of the patella, arthroscopy can be helpful. Patients with lateral tilt of the patella and subluxation who fail extensive nonsurgical treatment may benefit from realignment procedures. Cartilage restoration procedures for the patellofemoral joint have been met with mixed results. Isolated replacement of the patellofemoral joint for severe cartilage degeneration is infrequently performed. In order to accurately diagnose and treat the causes of anterior knee pain, an evaluation by an orthopedic surgeon is recommended.