Congenital pseudoarthrosis of tibia

1. Congenital pseudoarthrosis of tibia

2. INTRODUCTION
Failure of normal bone formation in the distal half of the tibia
 segmental defect of bone
Anterolateral angulation
Pathological fracture

3. Etiology
 NEUROFIBROMATOSIS:
most common cause in about 40-80% cases
hallmarks like café-au-lait spots and skin nodules
Absent at birth and appears later
 Fibrous dysplasia
 Idiopathic

4. PATHOLOGY
 Site is usually surrounded by thickened periosteum and fibrous tissue
 Thickened periosteum results in hamartomatous tissue
 Failure of callus formation resulting in pseudoarthrosis
 Appearance of strangulation of bone with atrophic changes followed by
avascular changes
 Failure of remodeling of bone results in stress fracture

5. Histopathology
 Fibrous hamartoma is the key pathology
 Low osteogenicity and high osteoclastogenicity
 Soft tissue at the pseudoarthrotic site is composed of variable of fibrous
tissue, fibrocartilage and hyaline cartilage with evidence of endochondral
ossification
 Marrow spaces are devoid of hematopoiesis
 This invasive fibromatosis is located in the periosteum and between broken
bone ends and surrounds the tibia causing compression, osteolysis and
persistence of pseudoarthrosis

7. ANDERSON CLASSIFICATION
 Dysplatic type
 Cystic type
 Late type
 Club foot type
 Angulated pseudoarthrosis

8. Dysplastic
 Diameter of tibia is narrowed
 Hourglass constriction is characteristic
 Tibia is bowed anteriorly or anterolaterally
 Prone to non- union and refracture
 Neurofibromatosis is always present in the dysplastic type
 It may be present at birth and develop at an average of 12 months

9. Cystic type
 Cyst like lesion in the affected segment
 No significant narrowing of diameter of tibia
 It may be present at about 8 months
 Neurofibromatosis not associated

10. Late type
 Affected leg shows length discrepancy
 After minimum trauma a stress fracture like break occurs with consequent
development of pseudoarthrosis.
 Not associated with neurofibromatosis
 Anterior bowing develops between age of 4 and 12 years

11. Club foot type
 Fracture present at birth in a leg with marked anterior angulation
 The involved or contralateral lower limb has other associated congenital
abnormalities such
constriction band
club foot

12. Angulated pseudoarthrosis
 Due to corrective osteotomy of anterior bowing of tibia
 Osteotomy results in pseudoarthrosis
 Therefore,simple osteotomy of anterior angulation is contraindicated

13. BOYDS CLASSIFICATION
 Type I
 Type II
 TypeIII
 TypeIV
 Type V
 Type VI
 Anterior bowing with tibia defect
 Pseudoarthrosis with hour glass constriction
 Pseudoarthrosis with bone cyst
 Sclerotic segments,March fracture
 Dysplastc fibula
 Interosseous neurofibroma

21. CLINICAL FEATURES
 Anterolateral,anterior rarely anteromedial bowing of the dysplastic tibia and
fibula
 Tibia and fibula affected at the same level
 Bowing increases during the first two years of life and eventually develops
pseudoarthrosis
 Patient walks with a limp or unable to walk

23. Criteria for diagnosis
 Mutiple café-au-lait spots(smooth edged,>0.5cm)
 Positive family history of neurofibromatosis
 Definite biopsy
 Bony lesions like pseudoarthrosis of the tibia

24. Radiological features
 Segment of tibia or tibia and fibula show hourglass thinning, sclerosis and
loss of medullary cavity
 Angulation at two levels proximally and distally with dysplastic changes

27. Treatment
 Complete excision of the soft tissue fibromatosis at the site of
pseudoarthrosis
 Correction of angular deformity
 Stimulation of bone healing
 Proper fixation of bone fragments

28. Treatment methods
 Ilizarov method
 Vascularized fibular graft
 Extending intramedullary nailing and bone grafting
 Electrical stimulation

29. Ilizarov technique

31. Intramedullary rod fixation
 The procedure of choice for the first attempt to gain union entails resection
of pseudoarthrosis, shortening and fixation with an intramedullary rod and
autogenous bone grafting
 The procedure can be performed can be performed at an y age and rates
of union of around 85% .

33. Complications
 Refracture
 Malalignment of tibia
 Limb length discrepancy
 Ankle valgus
 Ankle stiffness

34. Refracture
Shortening
Valgus deformity
 Splint the limb until skeletal
maturity,retain intramedullary nail
 Union of pseudo arthrosis as early as
possible, limb equalization procedure
 Ensure union of fibular pseudoarthrosis
 Retain intramedullary rod that crosses
the ankle joint

35. Thank you