Article

Pedikuloskopisch assistierte transpedikul�re Spongiosaplastik zur interkorporellen Fusion an der lumbalen Wirbels�ule Eine tierexperimentelle Untersuchung am Schafsmodell

Der Unfallchirurg (Impact Factor: 0.65). 07/2002; 105(8):680-687. DOI: 10.1007/s00113-001-0404-1

ABSTRACT

Objective. Failure of transpedicular bone-grafting in thoracolumbar burst-fractures has been proven. Possible reasons are insufficient disc-removal and difficult decortication of endplates. Methodical improvements are sought to make the procedure succeed in a sheep-model.
Method. 12 sheep with posterior instrumentation L4/L6 and transpedicular disc-removal L4/L5 underwent auto-grafting. Classical surgical technique was modified by bilateral approach and transpedicular endoscopic control. Animals were sacrificed 8 weeks p.op. For evaluation, radiology, histology, histomorphometry, and fluorochrome-analysis were employed.
Results. 10 animals could be evaluated. All revealed sufficient disc-removal and decortication with autograft-impaction into the lower vertebra L4. Main restoration took place before week 4 p.op. Fusion rate was 1/10. For 9/10 animals, defects in the disc-space were filled with metaplastic chondral-tissue; autograft was almost entirely resorbed.
Conclusions. Reason for failure of the method seems to be the insufficient primary stability of the posterior instrumentation, since satisfactory disc-removal and decortication alone cannot successfully modify the method.

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