Clinica Ortopedica e Traumatologica II, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy.
Dipartimento di Scienze per la Qualità Della Vita QUVI, Università di Bologna, Bologna, Italy.
Knee Surg Sports Traumatol Arthrosc. 2021 Dec;29(12):4138-4145. doi: 10.1007/s00167-021-06470-6. Epub 2021 Mar 3.
The aim of the present study was to trace knee position at the time of bone bruise (BB) and investigate how much this position departed from the knee biomechanics of an in vivo flexion-extension.
From an original cohort of 62 patients, seven (11%) presented bicompartmental edemas and were included in the study. 3D models of bones and BB were obtained from MRI. Matching bone edemas, a reconstruction of the knee at the moment of BB was obtained. For the same patients, knee kinematics of a squat was calculated using dynamic Roentgen sterephotogrammetric analysis (RSA). Data describing knee position at the moment of BB were compared to kinematics of the same knee extrapolated from RSA system.
Knee positions at the moment of BB was significantly different from the kinematics of the squat. In particular, all the patients' positions were out of squat range for both anterior and proximal tibial translation, varus-valgus rotation (five in valgus and two in varus), tibial internal-external rotation (all but one, five externally and one internally). A direct comparison at same flexion angle between knee at the moment of BB (average 46.1° ± 3.8°) and knee during squat confirmed that tibia in the former was significantly more anterior (p < 0.0001), more externally rotated (6.1 ± 3.7°, p = 0.04), and valgus (4.1 ± 2.4°, p = 0.03).
Knee position at the moment of Bone bruise position was out of physiological in-vivo knee range of motion and could reflect a locked anterior subluxation occurring in the late phase of ACL injury rather than the mechanism leading to ligament failure.
Level IV.
本研究旨在追踪骨挫伤（BB）时的膝关节位置，并探讨该位置与活体屈伸过程中的膝关节生物力学偏离程度。
从最初的 62 名患者中，有 7 名（11%）出现双间室水肿，被纳入研究。从 MRI 中获取骨骼和 BB 的 3D 模型。与骨水肿相匹配，重建了 BB 发生时的膝关节。对于同一患者，使用动态 X 射线立体摄影分析（RSA）计算了下蹲时的膝关节运动学。比较了描述 BB 时膝关节位置的数据与从 RSA 系统外推得出的同一膝关节运动学数据。
BB 时的膝关节位置与下蹲时的运动学明显不同。具体而言，所有患者的位置在前侧和胫骨近端平移、内外旋转（五例外旋，两例外旋）、内外旋转（均为外旋，仅一例为内旋）均超出了下蹲范围。在相同的屈曲角度下，将 BB 时的膝关节（平均 46.1°±3.8°）与下蹲时的膝关节进行直接比较，结果证实前者的胫骨明显更靠前（p<0.0001）、更外旋（6.1°±3.7°，p=0.04）和外旋（4.1°±2.4°，p=0.03）。
BB 时的膝关节位置超出了生理活体膝关节活动范围，可能反映了 ACL 损伤晚期发生的锁定性前半脱位，而不是导致韧带失效的机制。
IV 级。
