ObjectiveTo investigate the effectiveness of the arthroscopic lateral retinacular release combined with medial patellofemoral ligament (MPFL) reconstruction for patellar dislocation.MethodsBetween January 2016 and March 2017, 28 cases (32 knees) with patellar dislocation were treated by arthroscopic lateral retinacular release and MPFL reconstruction. There were 6 males (6 knees) and 22 females (26 knees) with an average age of 21 years (range, 17-29 years). The disease duration ranged from 2 days to 2 years (mean, 8 months). Apprehension test of all patients were positive. The preoperative Lysholm score was 68.34±12.26. Anteroposterior X-ray film showed the patellar subluxation or dislocation. The Q angle was (17.67±4.21)° and the distance of tibia tuberosity-trochlear groove was less than 20 mm. The femoral attachment of retinacular were fixed by the interference screws (16 knee) or the anchors (16 knee), respectively.ResultsAll incisions healed by first intention. All patients were followed up 6 months. The function of knee joint was significantly improved at 6 months after operation. The Lysholm score was 92.88±6.42 and the Q angle was (12.15±3.68)° at 6 months. There were significant differences in the Lysholm score and the Q angle between pre- and post-operation (t=–3.408, P=0.006; t=–2.317, P=0.004). Apprehension test of all patients were negative. No knee pain, knee weakness, and patellar dislocation occurred during follow-up. There was no significant difference in the Lysholm score and the Q Angle between the anchor group and interference screw group (t=–3.254, P=0.820; t=–3.576, P=0.940). ConclusionLateral retinacular release combined with MPFL reconstruction under arthroscopy can effectively improve the function of the knee joint for patients with Q angle less than 20° and TT-TG less than 20 mm, and the early effectiveness is good. There is no significant difference in knee function between the anchor and interference screw internal fixation.
Objective To review research progress on femoral attachment positioning during medial patellofemoral ligament (MPFL) reconstruction, so as to provide a reference for accurate positioning in clinic. Methods The literature at home and abroad on femoral attachment positioning during MPFL reconstruction was extensively reviewed and summarized. Results MPFL is the main ligament that restricts patellar outward migration, so MPFL reconstruction is the main treatment for patellar dislocation, but the accuracy of intraoperative femoral attachment positioning will significantly affect the effectiveness. At present, there are three main methods for femoral attachment positioning in MPFL reconstruction, including imaging positioning, bony landmark positioning, and new technology. Among them, the main imaging positioning method is the “Schöttle point” method, but it has high requirements for fluoroscopic positioning, and can only be accurately positioned under standard lateral fluoroscopy of the femur. The bony landmark positioning method mainly locates the femoral attachment by touching or dissecting the bony landmarks such as adductor tubercles and medial epicondyle of femur, but its disadvantages are that the positioning is not accurate enough, the intraoperative visual field exposure requirements are high, and a large incision is required. In order to avoid the problem that the simple bony landmark positioning method, in recent years, the combination of bony landmarks combined with arthroscopy, three-dimensional (3D) printing technology, and robot-assisted positioning methods have begun to be used in clinical practice. New technology localization methods have shown good results by preparing guides before operation, planning positioning paths in advance, or directly using robots to assist positioning during operation. Conclusion The accurate positioning of the femoral attachment in MPFL reconstruction is crucial, and the method of accurate and rapid intraoperative determination needs to be further improved and optimized. In the future, it is expected that the combination of computer image recognition correction technology and intraoperative position assistance will solve this problem.
Objective To review the influencing factors of medial patellofemoral ligament (MPFL) reconstruction for patellar dislocation. Methods The literature of MPFL reconstruction for patellar dislocation at home and abroad in recent years were summarized and analyzed. Results The influencing factors such as the location of the femoral insertion point, the tension and the fixed angle of the grafts, the dysplasia of the femoral trochlear before operation, the abnormal tuberositas tibiae-trochlear groove value, the high position of the patellar, and the tilting angle of the patellar, are all the factors affecting the effectiveness of MPLF reconstruction. Conclusion During MPFL reconstruction, the surgical techniques and elimination of other factors that caused patellar instability need to be focused in order to reduce the complications and operation failure.