Introduction
  • Spectrum of disease including
    • positional contractures
    • rigid dislocation
  • Structural components include
    • quadricep tendon contracture
    • anterior subluxation of hamstring tendon
    • absent suprapatellar pouch
    • tight collateral ligament
  • Often occurs in children with
    • myelomeningocele
    • arthrogryposis
    • Larsen's syndrome
  • Associated conditions
    • developmental dysplasia of the hip
    •  
      • 50% will have hip dysplasia affect one or both hips
    • clubfoot, 
    • metatarsus adductus
Classification                                                                                                                                                                                                                   
  • Tarek CDK Classification 
    • Graded by passive range of flexion and radiologic appearance
    • Can guide treatment
Presentation
  • Presents with hyperextened knee at birth
Treatment
  • Nonoperative treatment
    • reduction with manual manipulation and casting
      • indications
        • Tarek GI, initial treatment for GII (up to 1 month of age)
        • most cases can be treated nonoperatively
        • if both knee and hip dislocated, then treat knee first 
          • can't get Pavlik harness on hip if knee dislocated
      • technique
        • long leg casting on weekly basis
  • Operative treatment 
    • surgical soft tissue release
      • indications
        • failure to gain 30° of flexion after 3 months of casting
        • Tarek GII (identified after 1 month of age), GIII, and in recurrent cases 
      • goal of surgery is to obtain 90° of flexion 
        • percutaneous quadriceps recession (PQR)
        • quadriceps tendon lengthening (V-Y quadricepsplasty or Z lengthening) 
        • anterior joint capsule release
        • hamstring tendon posterior transposition
        • collateral ligaments mobilization
      • postoperative
        • cast in 45 to 60° flexion for 3 to 4 weeks