Study on the diagnostic value of different posterior cruciate ligament index measurement methods for anterior cruciate ligament injury / 中国骨伤

OBJECTIVE@#To compare the posterior cruciate ligament(PCL) index with six different measurement methods, and analyze and verify its clinical diagnostic value in anterior cruciate ligament (ACL) injury.@*METHODS@#The Magnetic resonance imaging (MRI) data of 225 knee joints in our hospital from May 2018 to March 2022 were retrospectively analyzed, aged from 18 to 60 years old, with a median of 32 years old. On the sagittal MRI images of 114 patients with ACL injury and 111 patients with intact ACL, Measure the straight-line distance (A) between the femoral attachment point and the tibial attachment point of the PCL on the MRI sagittal image and the maximum vertical distance (B) between the straight line and the arcuate mark point of the PCL on the sagittal image, calculate the PCL index and evaluate the diagnostic value of the PCL index for ACL injury.@*RESULTS@#The PCL index of the ACL normal group and the ACL injury group were statistically described. There was no significant difference in PCL index 1, 2, 3 and 6 between the two groups(P>0.05). The difference of PCL index 4 and 5 between the two groups was statistically significant (P<0.001). This study only found that the PCL index 2, 6 in the ACL normal group had a negative correlation with the patient's age (correlation coefficient=-0.213, -0.819;P<0.05), and the PCL index 5 in the ACL injury group was significantly correlated with the patient's body mass index(BMI)had a negative correlation (correlation coefficient=-0.277, P<0.05).@*CONCLUSION@#The change of PCL index is helpful for the diagnosis of ACL injury, PCL index 4 and 5 can be used as effective reference indexes for diagnosing ACL injury in clinic.

Fracturas avulsivas tibiales del ligamento cruzado posterior fijadas con tornillos: un estudio clínico y radiológico / Screw fixation of posterior cruciate ligament tibial avulsion fractures: a clinical and radiographic study

OBJETIVO: Realizar la evaluación clínica, imagenológica y funcional de pacientes con fracturas avulsivas tibiales del ligamento cruzado posterior (FTALCPs) fijadas con tornillos canulados con técnica abierta. MÉTODOS: Los pacientes con FTALCP operados entre 2010 y 2017 fueron revisados retrospectivamente. Criterios de inclusión: fracturas agudas, desplazadas, test de cajón posterior grado III, lesiones combinadas de rodilla, seguimiento > 12 meses. Se excluyeron pacientes > 65 años, con FTALCPs bilaterales, lesiones del ligamento cruzado posterior (LCP) intrasustancia, test de cajón posterior grados I-II, fracturas expuestas, lesiones neurovasculares, y seguimientos < 12 meses. Objetivo primario: medir la estabilidad clínica mediante test de cajón posterior y radiografía de estrés arrodillada comparativa. Objetivos secundarios: nvaluar la consolidación en radiografías, complicaciones y funcionalidad con las escalas de Lysholm y Tegner. Resultados Se incluyeron 20 pacientes, con edad media de 41 años (rango: 32 a 61 años). El seguimiento promedio fue de 33,9 meses (rango: 12 a 82 meses). La estabilidad clínica mejoró en 93% (cajón posterior postoperatorio grados 0 y I) de los pacientes. La radiografía de estrés arrodillada mostró una diferencia promedio de 2,6 mm (rango: 0,1 mm a 6,8 mm) de traslación posterior al comparar con el lado sano. Todas las fracturas consolidaron. Siete pacientes presentaron complicaciones. El puntaje promedio de la escala de Lysholm al final del seguimiento fue de 85,17. El promedio preoperatorio del puntaje en la escala de Tegner no varió significativamente en comparación con el postoperatorio. CONCLUSIONES: La fijación de fracturas avulsivas tibiales del LCP con tornillos canulados con técnica abierta es efectiva en restaurar la estabilidad posterior y lograr la consolidación ósea. La funcionalidad clínica a mediano plazo es buena, a pesar del alto número de complicaciones y lesiones concomitantes. NIVEL DE EVIDENCIA: tipo IV.

OBJECTIVE: To report mid-term clinical, radiographic, and functional outcomes following open reduction and fixation of posterior cruciate ligament tibial avulsion fractures (PCLTAFs) with cannulated screws. METHODS: This is a retrospective analysis of patients with PCLTAF operated on from August 2010 to April 2017. Patients with acute fractures, with more than 2 mm of displacement and grade III on the posterior drawer test, combined or not to knee injuries, were included. Patients older than 65 years of age, with bilateral avulsion fractures, intrasubstance posterior cruciate ligament (PCL) lesions, stable grade-I to -II on the posterior drawer test, concomitant neurovascular injuries, mid-substance tears, open fractures, and less than 12 months of follow-up were excluded. Primary outcomes: the clinical stability was assessed using the posterior drawer test and a single comparative knee stress radiograph. Secondary outcomes: radiographic consolidation, complications, Lysholm score, and Tegner activity score. RESULTS: In total, 20 patients with a mean age of 41 years (range: 32 to 61 years) were included. The mean follow-up was of 33.9 months (range: 12 to 82 months). Clinical stability (grade 0 or I on the posterior drawer test) was observed in 93% of the patients. The mean difference in contralateral posterior displacement was of 2.6 mm (range: 0.1 mm to 6.8 mm) on a single comparative knee stress radiograph. All fractures presented radiological consolidation. Seven patients developed complications. The mean Lysholm score at the last follow-up visit was of 85.17. The postoperative Tegner activity scores did no vary significantly compared to the preinjury scores. CONCLUSIONS: Cannulated screw fixation of a displaced PCLTAF through a posterior approach restores clinical and radiographic stability and has excellent union rates. The mid-term functional outcomes are good despite the high rates of combined knee lesions and postoperative complications. LEVEL OF EVIDENCE: IV.

Interposition of the Posterior Cruciate Ligament into the Medial Compartment of the Knee Joint on Coronal Magnetic Resonance Imaging

OBJECTIVE: The purpose of our study was to evaluate the overall prevalence and clinical significance of interposition of the posterior cruciate ligament (PCL) into the medial compartment of the knee joint in coronal magnetic resonance imaging (MRI). MATERIALS AND METHODS: We retrospectively reviewed 317 consecutive patients referred for knee MRI at our institution between October 2009 and December 2009. Interposition of the PCL into the medial compartment of the knee joint on proton coronal MRI was evaluated dichotomously (i.e., present or absent). We analyzed the interposition according to its prevalence as well as its relationship with right-left sidedness, gender, age, and disease categories (osteoarthritis, anterior cruciate ligament tear, and medial meniscus tear). RESULTS: Prevalence of interposition of PCL into the medial compartment of the knee joint was 47.0% (149/317). There was no right (50.0%, 83/166) to left (43.7%, 66/151) or male (50.3%, 87/173) to female (43.1%, 62/144) differences in the prevalence. There was no significant association between the prevalence and age, or the disease categories. CONCLUSION: Interposition of the PCL into the medial compartment of the knee joint is observed in almost half of patients on proton coronal MRI of the knee. Its presence is not associated with any particular factors including knee pathology and may be regarded as a normal MR finding.

Femoral Graft-Tunnel Angles in Posterior Cruciate Ligament Reconstruction: Analysis with 3-Dimensional Models and Cadaveric Experiments

PURPOSE: The purpose of this study was to compare four graft-tunnel angles (GTA), the femoral GTA formed by three different femoral tunneling techniques (the outside-in, a modified inside-out technique in the posterior sag position with knee hyperflexion, and the conventional inside-out technique) and the tibia GTA in 3-dimensional (3D) knee flexion models, as well as to examine the influence of femoral tunneling techniques on the contact pressure between the intra-articular aperture of the femoral tunnel and the graft. MATERIALS AND METHODS: Twelve cadaveric knees were tested. Computed tomography scans were performed at different knee flexion angles (0degrees, 45degrees, 90degrees, and 120degrees). Femoral and tibial GTAs were measured at different knee flexion angles on the 3D knee models. Using pressure sensitive films, stress on the graft of the angulation of the femoral tunnel aperture was measured in posterior cruciate ligament reconstructed cadaveric knees. RESULTS: Between 45degrees and 120degrees of knee flexion, there were no significant differences between the outside-in and modified inside-out techniques. However, the femoral GTA for the conventional inside-out technique was significantly less than that for the other two techniques (p<0.001). In cadaveric experiments using pressure-sensitive film, the maximum contact pressure for the modified inside-out and outside-in technique was significantly lower than that for the conventional inside-out technique (p=0.024 and p=0.017). CONCLUSION: The conventional inside-out technique results in a significantly lesser GTA and higher stress at the intra-articular aperture of the femoral tunnel than the outside-in technique. However, the results for the modified inside-out technique are similar to those for the outside-in technique.