Salvage Reconstruction of Congenital Pseudarthrosis of the Clavicle With Vascularized Fibular Graft After Failed Operative Treatment

Author(s): Glotzbecker MP, Shin EK, Chen NC, Labow BI and Waters PM

Source: J Pediatr Orthop 29(4): 411-415, 2009.

Summary:

Congenital pseudarthrosis of the clavicle is a rare condition.  There is controversy regarding indications for surgery but there appears to be a combination of aesthetic and symptomatic reasons for intervention.  The most common procedures involve resection of the pseudarthrosis, placement of iliac crest bone graft and internal fixation.  In the small number of cases reported, union is fairly uniform.   The authors report a 4 year old child treated with attempted internal fixation that subsequently went on to nonunion.  A free fibular was necessary to obtain union.

The child was 4 years age and underwent internal fixation of a clavicle pseudarthrosis at 3 years of age.  The initial technique consisted of excision of cartilaginous caps on both sides of the pseudarthrosis.  A calcaneal plate was used to span the resected area with two 3.5mm cortical screws at each end for fixation.  A combination of blood and Vitoss (Orthovita, Malvern, Pa), was placed at the pseudarthrosis site.  No iliac crest bone was utilized.  Subsequently, loosening of the hardware developed with osteolysis and a large defect.

Revision surgery required resecting a large amount of avascular scar that spanned the defect between the two ends of the clavicle.  There was little medial and lateral clavicle remaining, and the resultant defect measured 6 cm.  This required a free vascularized fibular graft harvested from the lower extremity.  An anastamosis was performed with the axillary artery.  Fixation was difficult and only a single 2.4mm was placed at both ends for fixation.  Postoperative immobilization included a spica cast.

Seven weeks after surgery, early union was evident and the child was placed in a removable shoulder abduction brace.  Fifteen months after surgery, the child was asymptomatic with good restoration of her shoulder girdle and overall improved cosmesis of the shoulder.  There are “lessons” from this case.  The initial procedure utilized a calcaneal plate with 3.5 mm fixation.  In addition, tricalcium phosphate was used as a scaffold to allow migration of nutrients, growth factors, and osteogenic cells that may promote the new bone growth.  Additional bone marrow aspirate was added to the procedure to improve union.  However, the most common procedure for this problem involves open reduction, removal of the prominent bone and placement of iliac crest bone graft with internal fixation utilizing a plate.  This technique should be the preferred procedure for children with clavicle pseudarthroses that require fixation.  Union is fairly uniform and this traditional approach may have prevented the need for a free vascularized fibular graft in this case.