Complex Knee Deformities and Ligamentous Injuries

Angular deformities involve abnormal alignment of the leg bones at the knee joint. Varus deformity (bow legs) causes the knees to angle outward while the ankles remain close together. Valgus deformity (knock knees) results in the knees angling inward with the ankles positioned apart. These deformities can be congenital or develop over time due to arthritis, previous injuries, or growth disturbances.

Rotational deformities occur when the bones above or below the knee twist abnormally. Internal tibial torsion causes the lower leg to rotate inward, while external tibial torsion results in outward rotation. Femoral anteversion or retroversion affects the thigh bone’s rotation. These conditions often cause abnormal gait patterns and increased stress on knee structures.

Multi-ligament injuries involve damage to two or more of the knee’s major ligaments simultaneously. This includes combinations of ACL (anterior cruciate ligament), PCL (posterior cruciate ligament), MCL (medial collateral ligament), and LCL (lateral collateral ligament) tears. These severe injuries typically result from high-energy trauma and often occur alongside other knee damage.

Post-traumatic deformities develop following severe knee injuries or fractures that heal improperly. These include malunion of fractures around the knee, chronic instability from untreated ligament injuries, or arthritis developing after trauma. Such deformities often combine alignment problems with ligament insufficiency.

• Occasional knee pain during activities
• Slight feeling of knee instability
• Minor swelling after prolonged standing or walking
• Subtle changes in walking pattern
• Mild stiffness in the morning
• Discomfort when climbing stairs
• Clicking or catching sensations in the knee

• Persistent knee pain affecting daily activities
• Visible knee deformity or abnormal leg alignment
• Frequent episodes of knee giving way
• Difficulty with sports or recreational activities
• Noticeable limp or altered gait
• Swelling that doesn’t fully resolve with rest
• Reduced range of knee motion
• Difficulty squatting or kneeling

• Severe, constant knee pain even at rest
• Complete inability to bear weight on affected leg
• Gross deformity visible to others
• Recurrent knee dislocations or subluxations
• Significant muscle wasting around the knee
• Development of secondary hip or ankle problems
• Inability to straighten or bend the knee fully
• Skin changes or wounds from abnormal pressure points

Symptoms typically develop gradually for deformities present from birth or childhood, while traumatic injuries cause immediate severe symptoms. The progression depends on the underlying cause and whether appropriate treatment is received.

Physiotherapy forms the cornerstone of non-surgical treatment for many knee conditions. Specialised exercises strengthen muscles around the knee, improve flexibility, and enhance proprioception (joint position awareness). Your physiotherapist will design a programme targeting your specific deficits and gradually progress exercises as you improve.

Custom knee braces provide external support for unstable knees and can help correct minor alignment issues. Unloader braces shift weight away from damaged areas in cases of localised arthritis. Shoe modifications or orthotics address leg length differences and improve overall alignment. These devices work for mild to moderate deformities.

Corticosteroid injections reduce inflammation and provide temporary pain relief for arthritic knees or chronic ligament injuries. Viscosupplementation using hyaluronic acid may improve joint lubrication and reduce symptoms. Platelet-rich plasma (PRP) injections potentially support healing of partial ligament tears, though results vary between individuals.

Minimally invasive arthroscopic surgery addresses specific internal knee problems. Procedures include meniscus repair or removal, cartilage smoothing, removal of loose bodies, and assessment of ligament injuries. While arthroscopy cannot correct significant deformities, it often forms part of staged treatment approaches.

Severe ligament injuries typically require surgical reconstruction using tissue grafts. ACL reconstruction restores anterior stability, while PCL reconstruction addresses posterior instability. Multi-ligament reconstructions involve complex procedures to restore overall knee stability. Surgery timing depends on associated injuries and the knee condition.

Osteotomy procedures involve precisely cutting and realigning bones to correct angular deformities. High tibial osteotomy corrects bow legs, while distal femoral osteotomy addresses knock knees. These joint-preserving surgeries redistribute weight across the knee and can delay or prevent the need for knee replacement in younger patients.

Arthritis with deformity may require knee replacement surgery. Specialised implants and surgical techniques address complex deformities during replacement. Revision surgery replaces failed previous knee replacements, often involving complex reconstruction techniques.

Severe cases may require staged surgical procedures combining ligament reconstruction with corrective osteotomy. Computer-assisted navigation ensures precise correction of deformities. Some patients need temporary external fixation devices to gradually correct severe deformities before definitive surgery.