[Complex instability of the anterior knee]

Area of Science:

• Orthopedic Surgery
• Sports Medicine
• Knee Biomechanics

Background:

• Complex knee instability involves the anterior cruciate ligament (ACL) and at least one other major knee stabilizer (medial collateral ligament (MCL), lateral collateral ligament (LCL), or posterior cruciate ligament (PCL)).
• Medial knee injuries have good healing potential and may not require surgery if ACL reconstruction is performed.
• Lateral knee injuries lack spontaneous healing potential and necessitate prompt surgical intervention within two weeks.

Purpose of the Study:

• To outline management strategies for complex knee instability.
• To differentiate treatment approaches for medial versus lateral collateral ligament injuries.
• To evaluate the efficacy of operative versus conservative treatment for multiligament knee injuries.

Main Methods:

• Review of management principles for complex knee instability.
• Analysis of indications for medial collateral ligament complex reconstruction.
• Comparison of operative (reconstruction and rehabilitation) versus conservative (immobilization) treatment for multiligament injuries in a European multicenter study.

Main Results:

• Medial ligament reconstruction is indicated for gross instability, medial meniscus dislocation, or large bony avulsions.
• Lateral injuries and frank knee dislocations require acute operative reduction and vascular assessment.
• Operative treatment with cruciate ligament reconstruction and rehabilitation showed superior results compared to immobilization.

Conclusions:

• Management of complex knee instability depends on the specific injured structures and severity.
• Prompt surgical intervention is crucial for lateral-sided injuries and severe dislocations.
• Surgical reconstruction and functional rehabilitation are more effective for multiligament knee injuries than conservative treatment.