Neglected Lateral Meniscus Root Tears and Sequalae by Dr. Robert F. LaPrade In this presentation, Dr. LaPrade shows the effects of missed or neglected lateral meniscus root tears. The first is an example of a 44 year old male who had a left knee twisting injury. He was diagnosed with LM root tear and was told to observe it, and he attempted to return to running. The patient had continued pain for 9 months and repeated the MRI which showed advanced lateral compartment arthritis and an extruded lateral meniscus. The second example is of a 20 year old patient who sustained a noncontact ACL tear and a LM root tear which was not treated at time of ACL reconstruction. At age 24 the patient complained of lateral joint pain and swelling. MRI showed a lateral compartment arthritis and an extruded LM with a LM root tear. And finally: The patient is a 28 year old who had an ACL reconstruction and an ignored LM root tear at age 20-now with a reinjury found to have advanced lateral compartment arthritis and an extruded LM . Dr. LaPrade emphasizes the role of the lateral meniscus root(s): - Serve an essential function as shock absorber for lateral compartment - Neglect of LM root tears can often lead to arthritis in this young population - The LM root is also essential to protect an ACL graft against increases in anterior tibial translation and internal rotation which can lead to ACL graft failure if not repaired.

1. z
Neglected
Lateral Meniscus
Root Tears and
Sequalae

2. z
44 year old male-left knee twisting injury-
Diagnosed with LM root tear-told to observe
it and he attempted to return to running

3. z
Patient had continued pain-9 months later
repeat MRI showed advanced lateral
compartment arthritis and an extruded LM

4. z
Patient is a 20 year old who sustained
noncontact ACL tear and a LM root tear which
was not treated at time of ACL reconstruction

5. z
Age 24-complained of lateral joint pain and swelling-
found to have lateral compartment arthritis and an
extruded LM with a LM root tear

6. z
Patient is a 28 year old who had an ACL
reconstruction and an ignored LM root tear at age 20-
now with a reinjury found to have advanced lateral
compartment arthritis and an extruded LM

7. z
Lateral Meniscal Roots
-Serve an essential function as shock
absorber for lateral compartment
-Neglect of LM root tears can often lead to
arthritis in this young population
-The LM root is also essential to protect an
ACL graft against increases in anterior tibial
translation and internal rotation which can
lead to ACL graft failure if not repaired