Wave plate fixation of an atrophic midshaft clavicular nonunion
Case description
One year after trauma a severely dislocated clavicular fracture did not heal in a 26-year-old woman. The midshaft clavicular nonunion showed no callus formation and even bone resorption. The typical deformity with the lateral fragment depressed and pulled posteriorly, and the medial fragment elevated was responsible for the nonunion.
Indication
The persistent dislocation causes pain, disability, and is also esthetically not acceptable.
Preoperative planning
This atrophic nonunion not only needs mechanical stabilization but also biological stimulation by bone grafts. At this level of the nonunion excessive callus formation after bone grafting at the inferior part of the clavicle may lead to brachial plexus impingement syndromes. To avoid this complication, a straight DCP 3.5 is waved away from the superior border of the clavicle to create space for a cancellous bone graft, stimulating superior, not inferior bridging callus formation. Both nonunion ends have to be debrided and connected with an intercalary corticocancellous bone graft to restore length. The cortical part of the inter-position bone-graft reconstructs the inferior surface of the clavicle and, therefore, avoids excessive callus formation in the area of the brachial plexus. Wave plate fixation under compression of the bone graft leads to full, rigid stability.
Equipment
Dynamic compression plate (DCP) 3.5 or reconstruction plate 3.5
Locking compression plates (LCPs) as alternative
(Size of system, instruments, and implants may vary according to anatomy.)
Patient preparation and positioning
The patient is positioned in a beach-chair position with a folded towel under the affected shoulder.
General anesthesia is preferred; it also allows harvesting of iliac bone grafts.
A single dose of 2nd generation of cephalosporin should be administered as a prophylactic antibiotic.
The anterior iliac crest is prepared for bone-graft harvesting.