New Way to Help Bone Grow in Children
Children have remarkable healing abilities but sometimes their fast growth just isn't enough. That's the case with large gaps in bone caused by tumor removal or traumatic fractures. To help bridge the gap, surgeons from Spain have developed a special technique called vascularized fibular periosteal graft. This report gives the results of a dozen children who received this treatment.
A fibular periosteal flap is a piece of bone taken from the fibula the smaller bone in the lower leg. A special tool called a periosteal elevator is used to lift the top layer of bone, which is then transferred to the site where it is needed.
The way in which the bone graft is placed in the defect depends on the underlying problem. For example, if a fracture hasn't healed (called a nonunion), then the periosteal flap is wrapped around the two ends of the bone in a "J" pattern. If the gap is from bone (tumor) removal, then the flap is used to bridge the gap by attaching it from one side to the other.
If the bone is used in the same leg, then blood vessels to the bone can be taken at the same time. This is called a pedicled graft. If the bone graft is used anywhere else, the donor bone is taken without attached blood vessels (called a free flap). With a free flap, the surgeon must perform microsurgery to connect the bone graft to local blood vessels (at the site of placement).
Once the procedure has been completed, the wait begins. In places where the bone is close enough to the surface, it may be possible to palpate or feel the new bone growing. New bone forms a callus (bony knob) that will eventually be remodeled by the body's own healing processes and become smooth once again.
The callus can often be felt two to three weeks after the bone graft procedure. Otherwise, serial (repeated) X-rays and CT scans can be used to assess results. Special ultrasound Doppler tests were used to monitor blood flow.
Using this new technique, the authors report success in all but one case. In the one case where it didn't work, the blood vessel attached to the bone graft was twisted so blood was not getting to the graft site. A second surgery to repeat this technique was successful.
Healing time with progressive bone formation ranged between two and nine months. The length of time for bone to fill in the gap depended on the location of the problem (e.g., middle of the bone versus near the growth plate). The final bone union occurred in two stages: first along the outside (periosteal layer) and then the layers underneath forming the cortical (inside) layers.
The authors conclude that this new technique using periosteal bone (with or without blood vessels attached) is an effective way to stimulate fast bone growth in children. It's not a method that is needed routinely but saved for children with complex bone loss too large to heal completely without some help.
Vascularized fibular periosteal graft is a new reconstructive strategy that works for children because of their unique ability to grow fast. This type of tissue transfer is successful because the bone has strong osteogenic (bone growth) properties and angiogenic (formation of blood vessels) abilities. Both the donor site and the graft site heal quickly and without problems.
Francisco Soldado, PhD, et al. Vascularized Fibular Periosteal Graft: A New Technique to Enhance Bone Union in Children. In Journal of Pediatric Orthopaedics. April/May 2012. Vol. 32. No. 3. Pp. 308-313.