Children's and Adolescents' Knee

The knee in children and adolescents

Due to increasingly early and intensive sport participation, the knees of children and adolescents are among the most frequent reasons for consultations with a paediatric orthopaedic surgeon. In sports, the knee is the most commonly severely injured joint requiring surgical treatment.

Additionally, children grow most in height "from the knee" – growth zones are most active there, cells divide rapidly, so malignant bone diseases in children are most common around the knee. However, benign conditions predominate. Children are often attributed knee pain due to rapid growth, and parents frequently report having had similar problems as children.

The knee joint consists of three bones: the lower end of the femur, the upper end of the tibia, and the patella. To improve the poor congruence between the joint surfaces of the femur and tibia, semi-lunar cartilaginous structures – the menisci – are situated between them. Numerous ligaments in and around the knee, together with tendons and muscles, provide stability. Each part of the knee can be a source of problems in a child.

Examination

Every examination begins with a conversation with the child and parent to establish the reason for the visit. If pain is the issue, it is necessary to establish when it appeared, how long it has lasted, whether it worsens with activity, and whether there was any injury. Children often do not remember a traumatic event – pain may appear gradually.

The character of pain matters – severe limiting pain differs from pain before sleep or only at night. Any swelling or skin colour change around the knee should be noted. It is important to know whether there is also restriction of movement, which might indicate a meniscal injury. Particular attention should be paid to a feeling of instability, which can be a sign of ACL rupture or patellar instability.

Physical examination

Physical examination includes:

• Inspection – observation of the entire leg, leg axes, knee contours, patella position, swelling
• Palpation – tenderness at the patella tip (Sinding-Larsen-Johansson disease); tenderness at the tibial tuberosity (Osgood-Schlatter disease); tenderness at the femoral condyle with snapping (osteochondritis dissecans)
• Ligament stability tests – specific tests for ACL, PCL, collateral ligaments and patellar ligaments
• Meniscal tests – using compression and rotation
• Range of motion – from full extension to approximately 150 degrees
• Quadriceps assessment – shortening of quadriceps muscles should be evaluated
• Hip examination – hip range of motion must be checked, as hip problems can manifest as knee pain

Imaging

• Ultrasound (US) – immediate in-clinic examination to confirm effusion, popliteal cyst or ligament status
• X-ray (RTG) – at least two projections (AP and lateral); axial view if patellar problems are suspected; panoramic X-ray for significant valgus or varus deformity
• MRI – needed for ligamentous, tendinous and cartilaginous structures not visible on X-ray

Specific knee conditions we treat

At Pediortos we specialise in the full range of paediatric and adolescent knee pathology:

• Knee Meniscus – meniscal tears including RAMP and ROOT lesions
• Anterior Cruciate Ligament (ACL) – rupture, reconstruction and primary repair
• Patellar Dislocation – primary traumatic dislocation and recurrent instability, MPFL reconstruction
• Medial Plica – symptomatic medial parapatellar plica syndrome