Poster 145: A Biomechanical Comparison of All-Inside versus Trans-tibial Meniscal Root Repair Techniques

OBJECTIVES: To evaluate the biomechanical characteristics of an all-inside meniscal root repair procedure versus transtibial repair METHODS: Nine paired cadaveric knees were prepared with pressure mapping sensors and underwent pressure testing to obtain peak pressures, average pressures, and femorotibial contact area in both the medial and lateral compartments. Testing was performed in three states: meniscus intact, meniscal root cut, and following meniscal root repair with all-inside repair technique. Additionally, testing was completed on eight pairs of cadaveric knees to compare stiffness and maximal load to failure between all-inside and transtibial meniscal root repair techniques. RESULTS: In the medial compartment, there were significant increases in both median peak pressures (p=0.017) and median average pressures (p=0.047) in the root cut state compared to the intact state (+636 kilopascal (kPA) [246-1026 95% confidence interval (95%CI)] and +190 kPA [49-330 95%CI] respectively). All-inside meniscal root repair restored median peak pressures and median average pressures to approach that of the intact meniscus (p=0.293; +311 kPA [-79-701 95%CI] and p=0.171; +137 kPA [-3-277 95%CI] respectively). In the lateral compartment, there were also significant increases in both median peak pressures (p=0.025) and median average pressures (p=0.05) in the root cut state compared to the intact state (+718 kPA [246-1191 95%CI] and +203 kPA [51-355 95%CI]) respectively). All-inside meniscal root repair restored median peak pressures and median average pressures to be not significantly different from the intact state (p=0.399; +322 kPA [-150-795 95%CI] and p=0.97; +18 kPA [- 134-171 95%CI] respectively). There was no difference between repair techniques regarding load to failure (p=0.896). CONCLUSIONS: All-inside meniscal root repair restores median peak and average pressures that approach that of the native, intact meniscus. Compared to a transtibial meniscal root repair technique, all-inside repair demonstrated equivalent load to failure.