One hundred patients with lateral patellar compression syndrome (LPCS) were recruited and divided into two groups: arthroscopic treatment group and rehabilitation conservative treatment group. A 2-year prospective cohort study was then conducted. The subjective scores of 5 scales and 3 objective indexes were used to evaluate the recovery of knee joint function after different treatment methods, and to further clarify the medium and long-term therapeutic effects of different treatment methods on LPCS patients.

Lateral patellar over-compression syndrome is a musculoskeletal disease characterized by increased pressure on the lateral patellofemoral joint, which is caused by long-term tilting of the patella, adaptive contraction of the lateral retinaculum and long-term stress imbalance of the medial and lateral articular surfaces. The main clinical manifestations are patellofemoral joint pain, abnormal patellar trajectory and articular cartilage injury. At present, the prevalence of anterior knee pain is as high as 8. 5% ~ 17. 0%, and female is higher than male. LPCS has become one of the main causes of anterior knee pain . There are many methods for the treatment of LPCS, some of which are still controversial. At present, the gold standard for the treatment of LPCS has not been determined.

In the clinical practice of the Institute of Sports Medicine and the previous scientific research of our group, we found that a considerable number of patients, after arthroscopic patella molding, lateral retinaculum release and joint cleaning, their pain was obviously relieved, the patella trajectory almost returned to normal, and the knee joint symptoms were well improved and returned to normal life.

Both arthroscopic surgery and conservative rehabilitation can be used to treat LPCS, but it has not been proved that the functional improvement and symptom improvement rate of the two treatment methods are better in the medium and long term follow-up. Based on the above background, this study will conduct a prospective cohort study, and plan to recruit 100 patients and divide them into two groups, namely the arthroscopic group and the conservative treatment group, for a 2-year follow-up. The patients' subjective scores of 5 scales and 3 objective indicators were used to evaluate the recovery of knee function after different treatment methods, and to further clarify the medium and long-term therapeutic effects of different treatment methods on patients with LPCS, in order to provide guidance and reference for the clinical treatment of LPCS.

Inclusion Criteria:

• ① Meet the diagnostic criteria of LPCS; ② Complete imaging data; ③ agree that the follow-up time should be at least 1 Years; ④ Those who are willing to conduct regular rehabilitation training can cooperate to complete the experiment by signing the informed consent.

Exclusion Criteria:

• ① Complicated with severe heart, brain, kidney and other organ dysfunction;② Combined with patellar instability, patellar dislocation or others Severe knee joint disease and injury; ③ The previous history of joint infection, joint tuberculosis or osteomyelitis, or the lower extremity in 6 A history of surgery within the last month and previous knee surgery; ④ Infection, cancer, pregnancy and mental disorders Those with special conditions. ⑤ patients with mental illness or cognitive impairment, unable to study and participate in rehabilitation training; ⑥ not Informed consent was obtained.