Knee Instability Following Fractures Around the Knee Joint: Diagnostic Dilemma and Management Challenges

Abstract

Aim

Knee instability following fractures around the knee joint is not uncommon but is often missed. They present challenges in identifying them during index injury or at follow-up. We share our experience of knee instability following fractures around the knee joint.

Purpose

(1) To identify the pattern of clinically significant knee instability following fractures around the knee joint. (2) To discern the association of fracture morphology with ligamentous disruption. (3) To identify the risk factors for knee ligament injury following fractures around the knee. (4) To recognise the signs of instability in fracture scenarios and their diagnostic pitfalls/management challenges.

Methods

After appropriate Ethical committee clearance and patient consent, a retrospective analysis of 595 fractures around the knee joint was performed at our institute from 2018 to 2021. After employing the exclusion criteria, a total of 92 cases of ligament injuries were included in the analysis. Seventy-six of them were identified and addressed during the index procedure, and 16 of them presented with delayed instability during fracture healing, treated by appropriate arthroscopic ligament reconstruction. Demographic data, mode of injury, fracture morphology, ligament injury pattern and associated injuries were documented and analysed. Functional outcome was assessed using Lysholm scoring and the International Knee Documentation Committee questionnaire at the final follow-up.

Results

The overall incidence of clinically significant knee ligament injury was 15.46%. Among the 76 acute cases, 8 were ACL avulsions, 47 were PCL avulsions, 9 were MCL injuries, 2 were LCL injuries, and 10 had MLKI treated by arthroscopic/open techniques. Out of the 16 cases that presented late, 6 had ACL injuries, 2 had LCL injuries, and 8 of them had a multi-ligamentous knee injury. With respect to the fracture pattern, 56 (60.9%) had tibia fractures, 24 (26.1%) had femur fractures, 3 (3.3%) of them had patella fractures, and 9 (9.8%) had floating knee injuries. The mean Lysholm score was 85.7 ± 9.8. 19.6% (n = 18) had excellent outcome, 46.7% (n = 43) had good outcome, 23.9% (n = 22) had fair outcome and 9.8% (n = 9) had poor outcome.

Conclusion

Knee instability following fractures around the knee is not uncommon, one out of six fractures may have significant instability. Identifying and addressing is key for a satisfactory outcome and to avoid its sequalae.