Description
Background: A detailed understanding of the anatomy of the quadriceps tendon (QT) in Japanese population is clinically relevant, owing to its increased use as a graft in anterior cruciate ligament (ACL) reconstruction.
Purpose: The purpose of this study is to investigate the morphological characteristics of the Japanese QT using preoperative ultrasound in ACL injured knees.
Study Design: Cross-Sectional Study
Methods: A total of 55 Japanese patients (32 male and 23 female; 28 right and 27 left knees) who were diagnosed with a complete ACL tear and were scheduled for primary ACL reconstruction at our institution were prospectively included in this study. Using ultrasound, short axis images of the QT were acquired in 10 mm increments from 10 to 90 mm proximal to the superior pole of the patella. The length of the QT was determined by the two contiguous images that did and did not contain rectus femoris muscle belly. The width of the superficial and narrowest part of the QT, the thickness of the central and thickest part of the QT were assessed at each assessment location.
Results: The mean age, height, weight, and BMI were 28.3 ± 11.5 years, 167.3 ± 9.7 cm, 69.0 ± 15.3 kg, and 24.4 ± 6.6, respectively. There was a significant positive correlation between patient height and QT length (r = 0.56, P < 0.01). The mean QT length was 65.7 mm (median 66mm, range 49 - 84 mm). The length of the QT was less than 60 mm in 16.4% of patients (9/55). The mean QT superficial width at 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm ,70 mm proximal to the superior pole of the patella were 29.4 mm, 28.0 mm, 25.8 mm, 24.0 mm, 20.4 mm, 16.1 mm, and 14.5 mm.
The thickest QT thickness was significantly greater at 10 mm and 20 mm than at 50 mm and 60 mm (P < 0.01). The QT was significantly wider and thicker more proximal to the patella.
Conclusions: The QT length was shorter than 60 mm in 16.4% of Japanese patients, which might be considered to be too short for an all–soft tissue QT autograft. The width and thickness of the QT were significantly greater at 10 mm and 20 mm than 50 mm and 60 mm proximal to the superior pole of the patella. Therefore, the size of the proximal part of the QT autograft may be smaller than the distal part if the QT autograft is harvested at 50 mm or more proximal to the superior pole of the patella. Assessing the morphology of the QT preoperatively using ultrasound may help surgeons to adequately reconstruct the native length and diameter of the ACL with a QT autograft.
