14512
document
The radial forearm flap : a biomechanical study of donor-site morbidity utilizing sheep tibia . The use of vascularized bone grafts to reconstruct extremity and mandibular defects is now commonplace in reconstructive surgery . Fibula , scapula , iliac crest , rib , and metatarsal as well as the radial forearm osseocutaneous flaps have all been utilized for this purpose . Troublesome spiral fractures of the distal radius are the most common fractures associated with the use of the distal radius as a vascularized bone-graft donor site . This study was proposed to investigate the effect of donor-site bone loss on the strength of the radius under torsional ( rotational ) loading . Previous clinical series and experimental studies have not examined this aspect of distal radius loading after harvesting the bone graft . Fifty pairs of sheep tibiae were utilized in the experiment . Five pairs were used in a pilot study and 45 pairs were used in the main experiment . Five pairs of human radii were used for the control in the pilot study . The pilot study attempted to make a comparison between the human radius and the sheep tibia for experimental purposes . For the biomechanical study of donor-site defects , four study groups were examined with random assignment and matched pairs . The control group ( group 1 ) had no alteration to the bone . Each test condition included five matched pairs of sheep tibiae . Experiment 1 compared the difference in the depth of the osteotomy defect . In doing this , one-third of the total length of the bone was removed in each of the following specimens to include ( 1a ) 30 percent of the cross-sectional area of the total bone , ( 1b ) 37 percent of the cross-sectional area of the total bone , and ( 1c ) 50 percent of the cross-sectional area of the total bone . In experiment 2 , the osteotomy shape was varied . Instead of the ends of the cuts being squared , the ends were beveled or rounded . Experiment 3 compared different lengths of bone removed in the osteotomy defect and included the following : In experiment 3a the diameter of the sheep tibia was measured at the incisura fibularis . This dimension was one diameter of bone , and a one-diameter length of bone was removed . In experiment 3b , a two-diameter length of bone was removed . In experiment 3c , a three-diameter length of bone was removed . In experiment 3d , a four-diameter length of bone was removed . ( ABSTRACT TRUNCATED AT 400 WORDS )
14513
Intervention_Surgical
vascularized bone grafts
14514
Intervention_Physical
no alteration to the bone
14515
Intervention_Surgical
one-third of the total length of the bone was removed
14516
Intervention_Surgical
osteotomy shape
14517
Outcome_Other
osteotomy defect .
14518
Outcome_Other
osteotomy shape
14519
Participant_Sample-size
Fifty
14520
Participant_Sample-size
Five
14521
Participant_Sample-size
45
14522
Participant_Sample-size
Five