Incidence and characteristics of ligamentous knee injuries accompanying a femur shaft fracture and their association with injury mechanism and fracture characteristics: A prospective-observational study in a low-middle-income country.

OBJECTIVE: This study aims to elaborate the incidence, types, and characteristics of ligamentous knee injuries accompanying femoral-shaft fractures and their association with demographic data, fracture characteristics, and injury mechanism.

METHODS: This multi-center-prospective-observational study examined patients in the Shaheed Mohtarma Benazir Bhutto Institute of Trauma and Civil Hospital orthopedic wards. Using the consecutive sampling technique, 146 patients with femoral-shaft fractures were recruited, and scrutinized to determine the presence of ligamentous knee injury, through an evaluation form encompassing patients' demographic data, fracture characteristics, knee examinations, and confirmed through magnetic resonance imaging. Knee injuries were detected intra-operatively under regional/general anesthesia and post-operatively utilizing diagnostic maneuvers (varus/valgus stress, Lachman, anterior/posterior drawer, external rotation recurvatum, and McMurray tests) by 2-3 surgeons and confirmed through magnetic resonance imaging. Magnetic resonance imaging was exclusively employed in suspected false positive/negative cases, and when a titanium implant was utilized, that is, 131 cases (89.7%). Chi-square test was used to assess the relationship between incidence and type of ligamentous knee injury with demographic data, injury mechanism, and fracture characteristics.

RESULTS: Among the 146 patients with femoral-shaft fractures, 78% and 22% were males and females, with 37% experiencing associated ligamentous knee injury. Medial collateral ligament and anterior cruciate ligament were the commonest types of ligamentous injuries accompanying femoral-shaft fractures, at 44% and 33%. The Chi-square revealed a statistically significant association between the incidence of ligamentous knee injury accompanying femoral-shaft fracture with demographic data, injury mechanism, and fracture characteristics ( p -value < 0.05), and was noted to be higher among males (55.6%), participants aged 18-25 years (66.7%), involved in a road traffic accident (88.9%), resulting in a complex (77.8%) and close fracture (88.9%). A similar association was seen between medial collateral ligament and anterior cruciate ligament injuries with age, injury mechanism, and fracture characteristics ( p -value < 0.05).

CONCLUSION: Our study revealed the unaddressed fact that Pakistan has a significant incidence of ligamentous knee injuries accompanying femoral-shaft fractures. These insights can empower clinicians/surgeons to understand and manage this condition effectively.