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An Analysis of the Causes of Failure in 57 Consecutive Posterolateral Operative Procedures

Purpose To investigate 57 failed posterolateral procedures in 30 consecutive knees to determine factors that may have contributed to the failure. Study Design Case series; Level of evidence, 4. Methods Thirty patient records were reviewed by an independent surgeon. The index posterolateral operations were done for 13 acute and 17 chronic knee injuries. The anterior cruciate ligament was ruptured in 17 knees, the posterior cruciate ligament was torn in 5 knees, and both cruciates were ruptured in 8 knees. In 25 knees, 46 revision posterolateral procedures had been performed, of which 27 had also failed (in 21 knees). Five knees did not undergo revision of the posterolateral structures. Results In 22 knees, multiple factors were identified that most likely contributed to the failure of the posterolateral procedures. The most common factors were nonanatomical graft reconstruction (23 knees), untreated varus malalignment (10 knees), and failure to successfully reconstruct all ruptured knee ligaments, including cruciates (27 knees). Thirty-nine anterior cruciate ligament procedures were done in 24 knees, including 24 primary and 15 revision operations. Seventeen posterior cruciate ligament procedures were done in 13 knees, including 13 primary and 4 revision operations. At the time of writing, 16 of 24 knees had a functional anterior cruciate ligament graft and 5 of 13 had a functional posterior cruciate ligament graft. Conclusion The results suggest greater emphasis during the index operation for anatomical graft reconstruction of one or more of the posterolateral structures as necessary, restoration of all ruptured cruciate ligaments, and correction of varus malalignment.