Abstract
Introduction
20 cases of bone defect have been treated by the induced membrane technique avoiding allograft, microsurgery and amputation
Material and Methods
9 cases of long bone defect (humerus and 2 bones arm) and 11 cases of bone defct at the hand have been included in this multicentric prospective study (3 centers). 11 cases were traumatic, 7 cases were septic non union and 2 cases were tumor. At hand level's bone reached at least one phalanx, and for long bone the mean defect was 5cm (3–11). All cases were treated by the induced membrane technique which consists in stable fixation, flap if necessary and in filling the void created by the bone defect by a cement spacer (PMMA). This technique needs a second stage procedure at the 2nd month where the cement is removed and the void is filled by cancellous bone. The key point of this induced membrane technique is to respect the foreign body membane which appeared around the cement spacer and which create a biologic chamber after the second time. Bone union was evaluated prospectively in each case by an surgeon not involved in the treatment by Xray and CT scan. Failure was defined as a non union at 1 year, or an uncontrolled sepsis at 1 month.
Results
3 cases failed to achieve bone union, 2 at hand level and 1 for long bone. No septic complications occured and all septic cases werre stopped. In 14 cases bone union was achieved with a delay of 5 months (1, 5–12). 2 biopsies allowed to proove us that osteoid tissue was created by the technic. At hand level all fingers have included. At shoulder and elbow level, function reached 75% of motion than controlateral side.
Discussion
Masquelet first reported 35 cases of large bone defect of tibia non union treated by the induced membrane technic which allow to fill bone defect with cancellous bone alone. The cement spacer allows to induce a foreign body membrane which constitute a biological chamber. Works on animal model reported by Pellissier and Viatteau showed the properties of the membrane: secretion of growths factors (VEGF, TGFbéta1, BMP2) and osteoinductive activitie of the cells. The induced membrane seem to play the role of a neo periosteum. Using this technic is possible in emergency or in septic condition where bone defect can not been solved by shortening. This technic avoids to use microsurgical technic and the limit is the quantity of avalaible cancellous bone.
