congenital pseudoarthrosis of tibia or anterolateral bowing of tibia is cause of major morbidity in children with no definitive or curative management.
2. INVESTIGATIONS:
• XRAY ( AP AND LATERAL RADIOGRAPHS)
• MRI
• Extent of the disease
• Preoperative planning to define borders precisely for resection
• Area of pseudoarthrosis is hyper intense on fat suppressed and T2-weighted images
and slightly hypo- intense on T1 weighted images with gadolinium enhanced contrast
studies
• CT SCAN
• To confirm the radiographic findings
3. MANAGEMENT DEPENDS ON
Age of the patient at which first fracture occurred (“early
onset”- <4 yrs, “late onset”- at or more than 4 yrs)
Presence or absence of fracture
7. Prophylactic
• First step in a child without fracture as prognosis after fracture
is poor
1. Caretakers education- infant before walking age.
2. Prophylactic bracing –once children start weight bearing.
o Clamshell type orthosis.
o Ankle joint should be free
o Continued till the child reaches skeletal maturity or until fracture has occured
3. Prophylactic bypass grafting
Modified posterior graft – “Strong and Wong-Chung”,
Between proximal and distal tibia bypassing the the deformity along concavity
1. Delayed McFarland graft – contralateral tibia
• Normal leg is disrupted
• No attempt is made at deformity correct
• 4-6 week interval between raising the graft and its subsequent harvesting from
original bed and transfer to affected side
2. Freeze dried fibular allograft
9. SURGERY
basic PRINCIPLES:
1.Resection of entire pseudoarthrosis and surrounding
hamartamatous tissue.
2.Restoration of mechanical allignment
These principles are augmented with bone transport ,
primary shortening, supplemental bone graft.
11. Intramedullary fixation
• Procedure of choice for first attempt to gain union
Resection of pseudoarthrosis
Shortening and fixation with intramedullary rod
Autogenous bone grafting
Fasciotomies are performed in all compartment
Separate lateral approach for pseudoarthrosis of fibula
Better results if performed <3 yrs but dealying surgery has advantages
such as
Allows growth of tibia
Better internal and external fixation
Increased availability of autogenous bone graft
Liklihood of amputation is magnified the earlier the first procedure is attempted
Subtalar joint (<5 yrs) an ankle joint(5-8 years ) should be included to
provide more stability.
Preferable to leave the rod in situ
Post operative – long leg cast or hip spica cast (6-8 weeks),long leg
weight bearing cast with knee on full extension(additional 1-2 months)?
Complications
Valgus deformity- relative growth inhibition of lateral portion of distal tibial physis, muscular imbalance,
Triceps surae atrophy and weakness- prolonged ankle immobiilaization
Limb length discrepancy
Weak and stiff ankle joint
13. Vascularized fibular graft
• second line procedure
• Ipsilateral fibula on its vascular pedicle or microvascular
transfer of contralateral fibula
14. External fixation and distraction
osteogenesis
• Bone transport technique or acute resection alignment plus
compression with proximal lengthening
• Simultaneous correction of deformity and shortening
• Illizarov procedure is used as a final treatment before
amputation
• Indications
o child more than 5 years
o Significant shortening
o Previous procedures
o Bilateral involvement
• Complications
o Refracture
o Growth disturbances
o Poor foot and ankle function(if ankle is included)
15. Augmenting procedure
• BONE MORPHOGENIC PROTEINS
o New modality
o rhBMP-2 and rh BMP-7
o Used in conunjction with intramedullary fixation
o Increase chances of union
• Periosteal grafting
o Harvested from medial ilium
• Electrical stimulation
o Increased calcification of cartilage
o Increased angiogenesis
o Direct stimulation using implanted electrode or pulsed electromagnetic field is
used
16. AMPUTATION
• Ultimate capitulation and acceptance of failure
• Resistant pseudoarthrosis
• History of multiple failed surgical procedures
• Stiffness
• Decreased function of limb that would be more useful
after an amputation and prosthetic fitting.