Biomechanical Analysis of Operative Methods in the Treatment of Extra-Articular Fracture of the Proximal Tibia

BACKGROUND: To determine relative fixation strengths of a single lateral locking plate, a double construct of a locking plate, and a tibial nail used in treatment of proximal tibial extra-articular fractures. METHODS: Three groups of composite tibial synthetic bones consisting of 5 specimens per group were included: lateral plating (LP) using a locking compression plate-proximal lateral tibia (LCP-PLT), double plating (DP) using a LCP-PLT and a locking compression plate-medial proximal tibia, and intramedullary nailing (IN) using an expert tibial nail. To simulate a comminuted fracture model, a gap osteotomy measuring 1 cm was created 8 cm below the knee joint. For each tibia, a minimal preload of 100 N was applied before loading to failure. A vertical load was applied at 25 mm/min until tibial failure. RESULTS: Under axial loading, fixation strength of DP (14,387.3 N; standard deviation [SD], 1,852.1) was 17.5% greater than that of LP (12,249.3 N; SD, 1,371.6), and 60% less than that of IN (22,879.6 N; SD, 1,578.8; p < 0.001, Kruskal-Wallis test). For ultimate displacement under axial loading, similar results were observed for LP (5.74 mm; SD, 1.01) and DP (4.45 mm; SD, 0.96), with a larger displacement for IN (5.84 mm; SD, 0.99). The median stiffness values were 2,308.7 N/mm (range, 2,147.5 to 2,521.4 N/mm; SD, 165.42) for the LP group, 4,128.2 N/mm (range, 3,028.1 to 4,831.0 N/mm; SD, 832.88) for the DP group, and 5,517.5 N/mm (range, 3,933.1 to 7,078.2 N/mm; SD, 1,296.19) for the IN group. CONCLUSIONS: During biomechanical testing of a simulated comminuted proximal tibial fracture model, the DP proved to be stronger than the LP in terms of ultimate strength. IN proved to be the strongest; however, for minimally invasive osteosynthesis, which may be technically difficult to perform using a nail, the performance of the DP construct may lend credence to the additional use of a medial locking plate.

Optimal Parameters for Sutures Tied to a Post during Anterior Cruciate Ligament Reconstruction: Thread Numbers, Knot Numbers, Suture Techniques and Stitch Numbers: An Experimental Laboratory Study Using Porcine Tendon / 대한스포츠의학회지

We evaluated the conditions required for sutures tied to a post for tibial fixation during anterior cruciate ligament (ACL) reconstruction. Harvested porcine tendon was used as a graft material and nonabsorbable suture was used for sutures. Samples were tested for ultimate tensile load and elongation according to thread numbers, knot numbers, suture techniques and stitch numbers. As thread numbers were increased, ultimate tensile load was increased and elongation was decreased. However, more than 4 strands of threads provided the sufficient ultimate tensile load more than 454 N of normal ACL for daily activities. As knot numbers were increased, ultimate tensile load was increased, but elongation was decreased. In terms of failure mode, unraveling occurred 100% in 3 and 4 knots, 81.2% in 5 knots, 54.5% in 6 knots, and 0% in 7 knots. Suture techniques and stitch numbers didn't significantly affect the ultimate tensile load and the elongation. For sutures tied to a post for tibial fixation in ACL reconstruction, more than 4 threads, more than 7 knots, and more than 4 stitches provide adequate ultimate tensile load and elongation.

An Anthropometric Study in Korean Humerus / 체질인류학회지

There were few studies about anatomic characteristics in Korean humerus recently. In addition, there was no comparison between Westerner (European and American) and Korean in anatomic characteristics of humerus. The aims of this paper are therefore to investigate anatomic characteristics in Korean humerus and to compare them with those of Westerner humerus. The seventy-two humerus (male : 66, female : 6) were scanned by computed tomography and three dimensional (3D) models of humerus were then reconstructed from acquired cross-section images. The twenty-one anatomic characteristics of the humerus were analyzed and were measured for each humerus. From the results, humeral head vertical diameter in the present study was generally bigger than that in the previous study (p0.05). Humeral head inclination angle, greater tuberosity lateral offset distance, humeral head height in Korean were generally bigger than those in Westerner (p<0.05). This study may contribute to develop an optimal implants and prostheses for the treatment of humerus fractures of Koran.