Chronic irreducible posterolateral knee dislocation: two-stage surgical approach

Area of Science:

• Orthopedic Surgery
• Knee Biomechanics
• Trauma Management

Background:

• Posterolateral knee dislocation is a rare injury, often requiring prompt reduction.
• Irreducible dislocations can occur due to interposition of soft tissues, complicating treatment.
• Chronic dislocations present unique challenges due to tissue changes and prolonged instability.

Observation:

• A 14-month history of irreducible posterolateral knee dislocation with associated anterior and posterior cruciate ligament (ACL, PCL) and medial collateral ligament (MCL) ruptures was observed.
• The patient exhibited limb valgus alignment, but the classic dimple sign was absent due to chronicity.
• Magnetic resonance imaging (MRI) failed to identify the specific tissues (thickened, meniscal-like) preventing reduction.

Findings:

• A two-stage surgical intervention was successful in treating the chronic irreducible dislocation.
• Stage one involved arthroscopic debridement of intervening tissues, knee reduction, and open MCL repair.
• Stage two focused on ACL and PCL reconstruction to restore knee stability.

Implications:

• This case underscores the importance of considering soft tissue interposition in chronic irreducible knee dislocations.
• Detailed clinical, radiographic, and advanced imaging review is crucial for accurate diagnosis and surgical planning.
• A staged surgical approach can effectively manage complex chronic knee dislocations, improving patient outcomes.