Miriam R Boot, Sebastiaan A W van de Groes, Esther Tanck, Dennis Janssen
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引用次数: 0
Abstract
Purpose: Lateral patellofemoral ligament (LPFL) reconstruction addresses medial patellar instability, but uncertainty regarding the optimal femoral attachment site may affect isometry and increase complication rates. This study aimed to establish landmarks for the femoral attachment of the LPFL graft based on in vivo isometry during active knee extension.
Methods: Dynamic computed tomography scans of 104 knees from 58 healthy participants were employed to examine flexion-extension movements. Length changes were assessed in approximately 1335 virtual LPFL graft fibres, which extended from the proximal one third of the patellar height to attachments across the femoral condyle. Four methods were evaluated for achieving (near-)isometric LPFL graft behaviour: three radiographic methods (R1-R3) and one anatomic method (A). Method R1 positioned the femoral attachment at a lateral equivalent of Schöttle's point, Method R2 at the centre of the trochlear groove arc, Method R3 at the centre of the lateral trochlear ridge arc and Method A at a point relative to the lateral epicondyle.
Results: Median length changes during extension were 7.7 mm (Method R1), 3.4 mm (Method R2), 2.7 mm (Method R3) and 3.0 mm (Method A). Method R3 demonstrated significantly smaller length changes compared to Methods R1 (p < 0.001) and R2 (p < 0.01), while Method A yielded smaller changes than Method R1 (p < 0.001). Notably, Method R1 resulted in continuous LPFL graft tightening throughout knee motion, whereas Methods R2, R3 and A showed initial tightening until 20° flexion, followed by slackening and near-isometric behaviour.
Conclusion: Femoral graft attachment is best determined at the centre of the lateral trochlear ridge arc (Method R3) or 15.1 mm anterior and 3.4 mm proximal to the lateral epicondyle (Method A). These guidelines help improve surgical precision and minimize complications in LPFL reconstructions.
期刊介绍：
Few other areas of orthopedic surgery and traumatology have undergone such a dramatic evolution in the last 10 years as knee surgery, arthroscopy and sports traumatology. Ranked among the top 33% of journals in both Orthopedics and Sports Sciences, the goal of this European journal is to publish papers about innovative knee surgery, sports trauma surgery and arthroscopy. Each issue features a series of peer-reviewed articles that deal with diagnosis and management and with basic research. Each issue also contains at least one review article about an important clinical problem. Case presentations or short notes about technical innovations are also accepted for publication.
The articles cover all aspects of knee surgery and all types of sports trauma; in addition, epidemiology, diagnosis, treatment and prevention, and all types of arthroscopy (not only the knee but also the shoulder, elbow, wrist, hip, ankle, etc.) are addressed. Articles on new diagnostic techniques such as MRI and ultrasound and high-quality articles about the biomechanics of joints, muscles and tendons are included. Although this is largely a clinical journal, it is also open to basic research with clinical relevance.
Because the journal is supported by a distinguished European Editorial Board, assisted by an international Advisory Board, you can be assured that the journal maintains the highest standards.
Official Clinical Journal of the European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA).
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