MARTIN JENTER, D.O., Pediatric Orthopaedic Resident

J. RICHARD BOWEN, M.D., Attending Pediatric Orthopaedic Surgeon

February 28, 1996






HISTORY: A 29 week old gestation male presented with bilateral knee dislocation, left hip subluxation, and right hip dislocation.

PHYSICAL EXAM: Right knee -30 to 20 degrees ROM, Left knee -20 to 20 degrees ; L. hip + Ortolani, R. hip - Ortolani

XRAYS: Reveal bilateral knee dislocations , and a left hip dislocation .

TREATMENT: Manipulation, skin traction and splint for knees

Hips were placed in traction for 2 weeks full time, and 6 weeks part-time( 12hr/day). The right hip failed traction: than had an open reduction and varus osteotomy at 1 year of age.

RESULT: ROM: R. knee 0-110 degrees, L. knee 0-120 degrees.; he started ambulating 18 months with a well reduced femoral head .


per 100,000 general population; in Denmark 1% of DDH population

Female > Male 10:3 ratio, One-third bilateral, equal right and left

Environmental: Fetal position, increased in Breech

Fetal knee: round condyles, tibial plateau slope 35 degrees posterior

absence or hypoplasia of cruciate ligaments

quadriceps fibrosis acquired

Associated with Larson's syndrome

  1. Quadriceps fibrosis and contracture
  2. Anterior subluxed tibia
  3. Hamstrings and ilio-tibial band anterior
  4. Absence suprapatellar pouch
  5. Underdeveloped or absent patella
  6. Hypoplastic or absent cruciates
  1. Grade I: minimum subluxation, knee 15-20 degrees. hyperextended, 45-90 degrees Flexion
  2. Grade II: displaced moderate, tibia anterior on femur, knee in 25-45 degrees hyperextension, flex to neutral
  3. Grade III: total displacement of tibia epiphysis, no contact, hip flexed, foot at mandible

1. Inspection, limited flexion

2. Ossification proximal tibia, distal femur hypoplastic or absent

3. Ultrasound: obliteration of suprapatellar pouch


Nogi and MacEwen reviewed 27 knee dislocations (17 patients) without associated syndromes

  • 50% associated with hip dislocations
  • Five (30%) premature infants
  • Seven (41%) breech
  • 23/27 success with closed treatment: immediate manipulation and casting
  • Pavlik Harness used in 8 patients
  • Open reduction 3 knees
  • Results: No extensor lag

    One patient with recurrent patella subluxation

  • 2 patients with only 90 o flexion
  • one with complaints
  • Austwick and Dandy operated on three knees after 8 weeks casting, ROM -45 to 45deg., ant-lat approach, tongue flap rectus, tight post cruciate release, both patients walked age 18 months, all knees 0-120 degrees ROM.

    Bell and Atkins treated 9 knees (5 children) operatively at average 9 months:

  • 4 girls, 1 boy
  • Unable to flex past 0 o at birth, had 45 o hyperextension
  • One with arthrogryposis had bilateral hip dislocations
  • All had ligamentous laxity
  • One child with Down's
  • Technique: required splitting quads full length, slide to double length V-Y flap. All patients had elongated ACL.

    Immobilization in 40 o , further flexion causes skin tightening, short tendoncast change at 3 weeks, flexion increased

    20-30 o x 6 weeks, then free ROM.

    Results: Extensor lag 30 o 8/9 knees, all patients walking independently. One case skin necrosis due to skin tension: casted at 60 o

    Conclusion: dislocation from either primary or secondary muscle imbalance. Neuromuscular disease cause weak flexors, strong extensors: shorten quads. Secondary cause: ant displaced hamstring with ant displaced tibia act as extensors: short quadriceps result.

    Johnson, Audell and Oppenheim reported on 23 knees in 17 patients:

    Recommend: treat knee & foot before hip, do closed hip reduction at time of open knee treatment; can maintain hip and knee reduction with spica cast.


    The case presented here illustrates the success of non-operative treatment. The patient exhibited several common findings for congenital knee dislocation to include premature birth and associated hip dislocation. Skin traction was used followed by splinting with resulting normal knee motion followed by treatment of the hips. No complications resulted from this treatment and the patient is a functional ambulator.

    Surgery is planned for congenital knee dislocation when failure to progress past 45 o flexion after 8 weeks or unable to reduce dislocation by manipulation or traction. Patients needing surgery have poorer result.

    1. Austwick, D.H., Dandy, D.J. Early operation for congenital subluxation of the knee. JPO 1983;3:85-7.
    2. Bell, M. J., Atkins, R.M., Sharrard, W.J.W. Irreducable congenital dislocation of the knee. JBJS 1987;69-B,3:403-406.
    3. Johnson, E., Audell, R. Congenital dislocation of the knee. JPO 1987;7:194-200.
    4. Lovell and Winter. Pediatric Orthopedics. Lippincott Press, Philadelphia. 1990;vol 2:756-67.
    5. Nogi, J., MacEwen, D. Congenital dislocation of the knee. JPO 1982;2:509-513.
    6. Tachdjian, M. Pediatric Orthopedics. Saunders company, Philadelphia. 1990;vol 1:609-