2023 ISAKOS Biennial Congress ePoster
Injury to Anterolateral Ligament and Kaplan Fibers Do Not Significantly Affect Preoperative Pivot-shift Test in Anterior Cruciate Ligament Injury
Takeo Tokura, MD, Kobe, Hyogo JAPAN
Kanto Nagai, MD, PhD, Kobe, Hyogo JAPAN
Yuichi Hoshino, MD, PhD, Kobe, Hyogo JAPAN
Shu Watanabe, MD, Kobe, Hyogo JAPAN
Kyohei Nishida , MD, PhD, Kobe, Hyogo JAPAN
Noriyuki Kanzaki, MD, PhD, Kobe, Hyogo JAPAN
Takehiko Matsushita, MD, PhD, Kobe, Hyogo JAPAN
Ryosuke Kuroda, MD, PhD, Kobe, Hyogo JAPAN
Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, Hyogo, JAPAN
FDA Status Not Applicable
Summary
The incidence of anterolateral ligament and Kaplan fiber of iliotibial band in anterior cruciate ligament injury was identified, and there association with magnitude of the preoperative pivot-shift test was evaluated by electromagnetic measurement system.
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Abstract
Background
The injury to secondary restraint plays an important role in anterolateral rotatory instability (ALRI) in anterior cruciate ligament (ACL)-injured knees. Recent biomechanical studies have shown that the concomitant injury to anterolateral complex (ALC), including the anterolateral ligament (ALL) and Kaplan fibers of iliotibial band (KF), may have a significant role in controlling ALRI. However, the detailed incidence of ALL and KF injuries and these effects on ALRI remain unclear in clinical setting.
Objectives: To investigate the incidence of ALL and KF injuries in patients with acute ACL injury on magnetic resonance imaging (MRI), and to investigate the association between these injuries and magnitude of the preoperative pivot-shift test measured by an electromagnetic measurement system (EMS).
Study Design: Retrospective cohort study
Method
One hundred and five patients with primary ACL rupture (age: 25.6 years, 52 males/53 females) whose MRI were taken within 90 days after injury, were retrospectively enrolled in the present study. The ALL injury and KF injury were assessed by MRI, and subjects were allocated into four groups accordingly: Group A, neither injury; Group B, only ALL injury; Group C, only KF injury; Group D, both injuries. Tibial acceleration (m/s2) during the pivot-shift test was measured by using the EMS as previously reported, just prior to ACL reconstruction under general anesthesia. Manual grading of the pivot-shift test was also recorded according to International Knee Documentation Committee (IKDC) guideline. These data were compared by using one-way ANOVA and Pearson’s chi-squared test (p<0.05). Tukey-Kramer method was used for post hoc analysis.
Results
The ALL was identified in 104 patients (99.1%) and KF was identified in 99 patients (94.3%) on MRI. Among 98 patients whose both ALL and KF were identified on MRI, injuries to ALL and KF were observed in 43 patients (43.9%) and 23 patients (23.5%), respectively. Patient distribution to each group was as follows; Group A: 43 patients (43.9%), Group B: 32 patients (32.7%), Group C: 12 patients (12.2%), Group D: 11 patients (11.2%). The age at injury was significantly younger in Group A (21.8 ± 10.1 years) than Group C (32.5 ± 12.2 years, p=0.033). No significant differences were observed in other patients’ demographics among four groups. No significant differences were observed in tibial acceleration (m/s2) during the pivot-shift test (1.4 ± 1.1, 1.4 ± 0.9, 1.4 ± 0.8, 1.7 ± 1.5, respectively; p=0.17), as well as manual grading of the pivot-shift test (p=0.25) among four groups.
Conclusion
More than half of the patients had concomitant injury to ALC including ALL and KF in ACL injury. However, no significant increase in the pivot-shift phenomenon was observed even in the ACL-injured knees with both ALL and KF injures. This finding suggests that the contribution of ALL and KF injuries detected by MRI to ALRI may be limited in ACL-injured knees in the clinical setting.