Objective To evaluate of the valgus stability of the elbow after excision of the radial head, release of the medial collateral ligament (MCL), radial head replacement, and medial collateral ligament reconstruction.Methods Twelve fresh human cadaveric elbows were dissected to establish 7 kinds of specimens with elbow joint and ligaments as follow:①intact(n=12)； ②release of the medial collateral ligament(n=6)；③ excision of the radial head(n=6)；④excision of the radial head together with release of the medial collateral ligament(n=12)；⑤radial head replacement(n=6)；⑥medial collateral ligament reconstruction(n=6)；⑦radial head replacement together with medial collateral ligament reconstruction(n=12). Under two-newton-meter valgus torque, and at 0, 30, 60, 90 and 120 degrees of flexion with the forearm in supination, the valgus elbow laxity was quantified: All analysis was performed with SPSS 10.0 software.Results The least valgus laxity was seen in the intact state and its stability was the best. The laxity increased after resection of the radial head. The laxity was more after release of the medial collateral ligament than after resection of the radial head (P lt;0.01). The greatest laxity was observed after release of the medial collateral ligament together with resection of the radial head, so its stability was the worst. The laxity of the following implant of the radial head decreased. The laxity of the medial collateral ligament reconstruction was as much as that of the intact ligament (P gt;0.05). The laxity of the radial head replacement together with medial collateral ligament reconstruction became less.Conclusion The results of this studyshow that the medial collateral ligament is the primary valgus stabilizer of the elbow and the radial head was a secondary constraint to resist valgus laxity.Both the medial collateral ligament reconstruction and the radial head replacement can restore the stability of elbow. If the radial head replacement can notbe carried out, the reconstruction of the medial collateral ligament is acceptable. 

Citation： JIANG Tao,HUANG Fuguo,PENG Jiaying,et al.. BIOMECHANICAL EVALUATION OF THE VALGUS STABILITY OF ELBOW AFTER RECONSTRUCTION. Chinese Journal of Reparative and Reconstructive Surgery, 2005, 19(2): 141-144. doi: Copy