Sevim Ömer Faruk, Ergün Selim, Şahin Ediz Suna, Eceviz Engin, Karahan Mustafa
Department of Orthopaedic Surgery, Kartal Dr Lutfi Kirdar City Hospital, Istanbul, Turkey.
Department of Radiology, Kartal Dr Lutfi Kirdar City Hospital, Istanbul, Turkey.
Orthop J Sports Med. 2024 May 7;12(5):23259671241247524. doi: 10.1177/23259671241247524. eCollection 2024 May.
The posterior tibial slope (PTS) is an important feature in knee joint biomechanics and indicates anterior-posterior knee stability. Increased PTS is a known risk factor for both primary anterior cruciate ligament (ACL) rupture and postreconstruction rerupture.
To investigate the effect of long-term exposure to ACL deficiency on the PTS and the sagittal anatomy of the proximal tibia.
Cross-sectional study; Level of evidence, 3.
A total of 44 patients (38 men, 6 women) with a history of knee injury and ACL rupture confirmed by magnetic resonance imaging and physical examination were included in this study. Patients were divided into those with chronic ACL deficiency (group 1: injured ≥5 years prior; n = 22) and acute ACL deficiency (group 2: injured <1 year prior; n = 22). The medial and lateral tibial plateau PTS and anterior tibial translation were measured on monopodal weightbearing knee radiographs at 20° of flexion. The mechanical tibiofemoral angle (MTFA) and the medial proximal tibial angle (MPTA) were measured using an orthoroentgenogram. The side-to-side difference between the affected and unaffected knees was also calculated for all measurements.
The mean duration of exposure to ACL deficiency was 7.6 years (range, 5-15 years) in group 1 and 4.4 months (range, 1-11 months) in group 2. Regarding the side-to-side differences in angular measurements, a higher medial PTS (affected vs unaffected: 12.4° vs 10.1°; = .007), higher lateral PTS (11° vs 8.9°; = .011), and increased varus alignment on both the MTFA (4.3° vs 2.4°; = .036) and the MPTA (84.9° vs 86.3°; = .033) were found in group 1, while no significant differences in angular measurements were found in group 2. Compared with group 2, patients in group 1 had a significantly higher side-to-side difference in the medial PTS (2.3° vs 0.1°; = .0001), lateral PTS (2.1° vs 0.4°; = .0001), and MPTA (1.4° vs 0.1°; = .002).
This study showed that the affected knees of patients with chronic ACL deficiency (≥5 years) had higher medial and lateral PTS compared with the unaffected contralateral knees. Therefore, when planning ACL reconstruction for patients with a history of long-term ACL deficiency, it is crucial to measure the preoperative PTS accurately.
胫骨后倾坡度（PTS）是膝关节生物力学的一个重要特征，提示膝关节前后稳定性。PTS增加是原发性前交叉韧带（ACL）断裂和重建后再断裂的已知危险因素。
探讨长期ACL缺失对PTS及胫骨近端矢状面解剖结构的影响。
横断面研究；证据等级：3级。
本研究纳入44例经磁共振成像和体格检查确诊有膝关节损伤及ACL断裂病史的患者（38例男性，6例女性）。患者分为慢性ACL缺失组（第1组：受伤时间≥5年；n = 22）和急性ACL缺失组（第2组：受伤时间<1年；n = 22）。在屈膝20°单足负重膝关节X线片上测量胫骨内外侧平台PTS及胫骨前移。使用正位X线片测量机械性胫股角（MTFA）和胫骨近端内侧角（MPTA）。所有测量均计算患侧与未患侧膝关节的左右差异。
第1组ACL缺失的平均暴露时间为7.6年（范围5 - 15年），第2组为4.4个月（范围1 - 11个月）。关于角度测量的左右差异，第1组患侧内侧PTS更高（患侧与未患侧：12.4°对10.1°；P = .007），外侧PTS更高（11°对8.9°；P = .011），MTFA（4.3°对2.4°；P = .036）和MPTA（84.9°对86.3°；P = .033）的内翻对线增加，而第2组在角度测量上未发现显著差异。与第2组相比，第1组患者在内侧PTS（2.3°对0.1°；P = .0001）、外侧PTS（2.1°对0.4°；P = .0001）和MPTA（1.4°对0.1°；P = .002）的左右差异上显著更高。
本研究表明，慢性ACL缺失（≥5年）患者的患侧膝关节与未患侧对侧膝关节相比，内侧和外侧PTS更高。因此，在为有长期ACL缺失病史的患者计划ACL重建时，准确测量术前PTS至关重要。
