THE PLANOVALGUS FOOT IN CEREBRAL PALSY

DAVID J. ABRAHAM, M.D., Resident, Orthopaedic Surgery

FREEMAN MILLER, M.D. Attending Pediatric Orthopaedic Surgeon

March 26, 1996

CLINICAL CASE PRESENTATION

ORTHOPAEDIC DEPARTMENT

THE ALFRED I. DUPONT INSTITUTE

WILMINGTON, DELAWARE

CASE HISTORY:

A six year-old female followed for spastic quadriplegic cerebral palsy presented with increasing difficulty with ambulation secondary to bilateral hamstring tightness and progressive planovalgus deformity of the feet. The patient was managed conservatively with bilateral MAFOs for two years but noticed increasing difficulty planting her feet during ambulation. The patient had no complaints of pain in the feet with ambulation.

PHYSICAL EXAM:

Examination revealed a small thin six year-old female with severe bilateral planovalgus deformity. She is able to flex both hips to 120 degrees and has 60 degrees of hip abduction. Her popliteal angles are 60 degrees bilaterally. Her internal rotation is 30 degrees bilaterally and external rotation is 80 degrees bilaterally. Her ankles dorsiflex to 20 degrees with knee flexion and 0 degrees with her knees extended. While walking, the bilateral planovalgus deformity causes her to bear weight on her medial midfoot.

RADIOGRAPHIC EXAM:

Preoperative weight-bearing lateral radiographs of the feet reveal the following:

Preoperative X-rays:

Video Gate Analysis (preop)

Clinical Course

The patient failed conservative management with bracing and therefore had a bilateral subtalar arthrodesis with lateral column lengthening and gastrocnemius lengthening . Post-operatively, the patient was placed in bilateral short leg casts and allowed full weight bearing.

At 15 month follow-up the patient had a decrease in her popliteal angles to 20 degrees and was ambulating with plantigrade feet in neutral varus/valgus angulation.

Postoperative X-rays:

Video Gait analysis (postoperative)

DISCUSSION

Goals of surgical intervention in planovalgus deformity of the feet in C.P.:

  1. Complete unassisted walking brace-free with a heel-toe gait
  2. Minimize the risk of growth disturbance
  3. Minimize the risk of late degenerative joint disease

Biomechanics of the planovalgus foot deformity:

Surgical Alternatives:

  1. Grice extra-articular subtalar fusion
  2. Calcaneal medial displacement osteotomy (Koman, 1993)
  3. Arthroereisis of subtalar joint with vitallium staples
  4. Triple arthrodesis
REFERENCES:
  1. Aiona M. Triple arthrodesis in cerebral palsy: Long-term results(abstract). Orthop Trans 1993; 16:626.
  2. Barrasso JA, Wile PB, Gage JR. Extra-articular subtalar arthrodesis with internal fixation. J Pediatr Orthop 1984; 4:555.
  3. Bennet GC, Rang M, Jones D. Varus and valgus deformities of the foot in cerebral palsy. Dev Med Child Neurol 1982; 24, 499.
  4. Crawford AH, Kucharzuk D, Roy DR, Blibo J. Subtalar stabisization of the planovalgus foot by staple arthroeresis in young children who have neuromuscular problems. J Bone Joint Surg [Am] 1990; 72: 840.
  5. Dennyson WG, Fulford GE. Subtalar arthrodesis by cancellous grafts and metallic internal fixation. J Bone Joint Surg [Br] 1976; 58: 187.
  6. Evans D. Calcaneo-valgus deformity. J Bone Joint Surg [Br] 1975; 57: 270.
  7. Grice DS, An extra-articular arthrodesis to the sub-astragalar joint for correction of paralytic flat feet in children. 34A: 927-940, 1952.
  8. Keats S, Early surgical correction of the planovalgus foot in cerebral palsy. CORR 61, 223, 1968.