Congenital pseudarthrosis of tibia

congenital pseudoarthrosis of tibia

1. CONGENITAL
PSEUDARTHROSIS OF TIBIA
Dr. Sidharth Yadav
Orthopaedic Dept.
N.K.P.SIMS

2. DEFINITION
Pseudarthrosis is a
false joint associated
with abnormal
movements at the site

3. INTRODUCTION
Congenital pseudarthrosis of tibia refers to nonunion of
tibial fracture that develops spontaneously or after trival
trauma in a dysplastic bone segment of tibia diaphysis.
CPT is rare & Usually develops in first 2 yrs of life.
Etiology is unclear.
Incidence is 1: 250,000
There is a strong association of CPT with
neurofibromatosis type 1.

4. CLINICAL FEATURES
Associated with anterolateral
bowing of tibia.
Bowing usually occurs at the
junction of middle & distal third.
Deformity may be associated with
skin dimple, limb shortening,
dysplasia of fibula & ankle valgus.
Usually unilateral.

5. NEUROFIBROMATOSIS
NF-1 occurs due to mutation on the gene coding for
NEUROFIBROMIN on chromosome 17.
Neurofibromin is expressed in a broad range of cells & tissue
type.
It negatively regulates Ras activity ( cell proliferation &
function)
It’s deficiency leads to increased Ras activity.
Affects Ras-dependent MAPK( mitogen activated protein
kinase) activity which is essential for osteoclast function &
survival.

6. SIGNS OF
NEUROFIBROMAT
OSIS

7. DIAGNOSTIC CRITERIA OF
NEUROFIBROMATOSIS
6 or more café-au-lait macules (>5mm before puberty &
>15mm after puberty).
Axillary or inguinal freckling.
2 or more neurofibromas or 1 plexiform neurofibroma.
2 or more Lisch nodules.
Optic glioma.
A distinctive osseous lesion such as sphenoid dysplasia or
thinning of long bone cortex with or without pseudarthrosis.
A first degree relative with NF-1.

8. PATHOLOGY
Unclear
Recent studies have shown that there is hyperplasia of
fibroblast with the formation of dense fibrous tissue.
This invasive fibromatosis is located in the periosteum &
between broken bones ends causing compression,
osteolysis & persistance of pseudarthrosis.

10. PATHOLOGY
Paley et al theorized that pathology of pseudarthrosis is not
bony but rather its periosteal in origin.
This theory was also considered by CODAVILLA a century
ago.
This theory is supported by following observation :-
Thickening with hamartomatous transformation of periosteum.
Appearance of strangulation of bone with atrophic changes
followed by avascular changes.
Failure of remodelling of pin tracts leading to stress fractures.

11. PATHOLOGY
Pathologic analysis of HERMANNS-SACHWEB et al
confirmed that pathologic periosteum is the cause of
CPT.
There finding was :-
Neural cells form a tight sheath around the periosteal
vessels.
Peiosteum undergoes hypoxemic changes resulting in the
formation of a thick fibrous cuff.
Leads to impaired oxygen & nutrient supply to the
subperiosteal bone & atrophic changes are observed.

12. CLASSIFICATION
There is no universally agreed system based on both
clinical features & radiographic findings.
CAMURATI - 1930
ADGLEY - 1952
BOYD - 1958
APOIL - 1970
ANDERSEN - 1973
CRAWFORD - 1986
CRAWFORD - 1999
BOYD & ANDERSEN are commonly used.

13. BOYD CLASSIFICATION
Boyd divided CPT into 6 types :-
Type 1 :-
Pseudarthrosis occurs with anterior
bowing.
A defect in tibia present at birth.
Other congenital deformities may be
present which may affect the
management of pseudarthrosis.

14. BOYD CLASSIFICATION
Type 2 :-
Pseudarthrosis occur with anterior bowing & a hourglass constriction of
the tibia is present at birth.
Spontaneous fractures or after minor trauma.
Commonly occur before 2 yrs of age.
Also known as HIGH RISK TIBIA.
Tibia is tapered, rounded, sclerotic & obliteration of medullary canal.
Most common type.
Associated with NF-1
Poorest prognosis.

15. BOYD CLASSIFICATION
Type 3 :-
Pseudarthrosis develops in a congenital cyst
usually near the junction of middle & distal
third of tibia.
Anterior bowing may precede or follow the
development of fracture.
Recurrance of fracture is less common after
treatment.

16. BOYD CLASSIFICATION
Type 4 :-
Originates in a sclerotic segment of
bone.
Without narrowing of tibia.
Medullary canal is partially or
completely obliterated.
An insufficiency or stress fracture
develops in the cortex of tibia &
gradually extends through the sclerotic
bone.
Prognosis is good.

17. BOYD CLASSIFICATION
Type 5 :-
Pseudarthrosis of tibia occurs with a dysplastic fibula.
Pseudarthrosis of both bone may develop.
Prognosis is good if the lesion is confined to fibula.
If the lesion progress to tibia then the natural h/o usually
resembles type 2.
Type 6 :-
Occurs as an intraosseous neurofibroma or schwannoma
Extremely rare.

18. CRAWFORD CLASSIFICATION
Divided broadly divided into 2 types:-
Non-Dysplastic
Anterolateral bowing with increased density & sclerosis of
medullary canal.
Dysplastic
Anterolateral bowing with failure of tubularization.
Cystic changes.
Frank pseudarthrosis.

19. ANDERSEN CLASSIFICATION
Also divided into 6 types :-
Club foot
Cystic
Late
Fibular
Dysplastic
Angulated

20. CLASSIFICATION BY PALEY

21. TREATMENT
Treatment of CPT depends upon age of the patient & type of
pseudarthrosis.
Decision has to be taken whether to attempt to secure union
or amputation is the treatment of choice.
No single treatment approach has proven ideal .
True pseudarthrosis does not heal when treated with casting
alone.

22. TREATMENT
Goals of treatment :-
Complete excision of the soft tissue fibromatosis at the
site of pseudarthrosis.
Correction of angular deformity.
Stimulation of bone healing.
Proper fixation of bone fragments.
Postoperative protection .

23. TREATMENT
Is divided into 2 types :-
Prophylactic :-
Decreased activity.
Orthotics or cast.
Curettage with bone grafting.
Active :-
Surgical treatment

24. TREATMENT
Bone grafting
IM fixation
Ilizarov fixation
Free vascularized fibular grafting
Amputation
Bmp(bone morphogenic proteins).
Electric stimulation.

26. VASCULARISED FIBULA GRAFTING
Advantages :-
Primary bone lengthening
Correction of deformity.
Union occur in a relative short
period.
Disadvantages :-
Development of valgus deformity of
normal ankle.

27. ILIZAROV FIXATION
Advantages :-
Provides stability.
Enables full wt. bearing.
Allows limb lengthning &
segmental transport.
Disadvantages :-
Pin tract infection
Ankle stiffness.

28. AMPUTATION
Anticipated shortening of more then 2 or 3 inches.
Multiple failed surgical procedure.
Stiffness & decreased function of the limb that will be
more useful after amputation & fitting with prosthesis.

29. BONE MORPHOGENIC PROTEIN
16 different BMP have been identified.
BMP-2 & BMP -7 are the only current available for the
clinical use in non-union & paeudarthrosis.
Clinical studies have shown that BMP-2,6,9 plays an
important role in early differentiation of mesenchymal
progenitor cells to preosteblasts.
BMP-7 promotes early differentiaiton of preosteoblast to
osteoblast.

30. PSEUDARTHROSIS OF FIBULA
Pseudarthrosis of fibula often precedes or
accompanies the same condition in ipsilateral tibia.
Several grades are seen :-
Bowing of fibula without pseudarthrosis.
Pseudarthrosis without ankle deformity.
With ankle deformity.
Fibular pseudarthrosis with latent tibia pseudarthrosis.
Progressive valgus deformity is developed.

32. TREATMENT
Until skeletal maturity –ankle foot orthosis.
At maturity :- supramalleolar osteotomy
Langenskiöld has devised an operation for children to
prevent valgus deformity & halt its progression—
SYNOSTOSIS.

33. THANK YOU…