Bicruciate ligament avulsions, lateral meniscus dual root avulsions - "Tibial Avulsion Tetrad"- with menisco- capsular injury - Floating meniscus in innocuous looking proximal tibia fracture.

INTRODUCTION: Bicruciate bony avulsion fracture with osseous avulsions of dual root LM in combination with posterior horn LM meniscocapsular injury causing floating meniscus in lateral tibial plateau depressed fracture is a very rare complex injury which was managed carefully with a proper work up and surgical planning to get excellent functional outcome. Few times innocuous looking tibial plateau fractures can reveal severe hidden injuries which have potentials of disastrous complications later in the life and therefore high degree of suspicion is required for accurate diagnosis. CASE REPORT: 22 year old female patient injured her knee while playing kabaddi due to severe hyperextension injury. Based on clinicoradiological and intraoperative findings, she was diagnosed as having both ACL and PCL avulsion fractures with LM anterior and posterior root avulsion which we coined new term as " Terrible Avulsion Tetrad" alongwith posterior horn of LM menisco-capsular tear with depressed lateral tibial plateau. Patient was operated next day of the injury with both arthroscopic and open procedures. Arthroscopically , ACL and both root tear of LM were fixed with tunnel pull out suture technique using No. 2 fibrewires and fixing with endobutton and suture disc. Posterior horn LM menisco-capsular junction tear was repaired with two all-inside meniscal sutures. Lateral tibial plateau was fixed with two CC screws after elevating depressed fragments. Posteriorly PCL avulsion fragment was fixed with open procedure with inverted L incision and two cannulated cancellous screws. Patient was put on knee brace for 6 weeks and was allowed knee range of movements at 3 weeks. Patient was kept on non-weight bearing for 3 months. At 24 months follow up , radiology showed complete union of fractures. Functional assessment using Lysholm knee score showed excellent outcome with score of 96 and she was back to her routine activities. CONCLUSION: Combination of bicruciate and meniscus osseous root avulsions extremely rare. Further rare injury combination can include floating meniscus as a result meniscocapsular junction tear alongwith osseous root avulsion of meniscus. All these injuries can be accompanied in subtle looking proximal tibia plateau fracture which needs be properly worked up.