Arthroscopic Segmental Medial Meniscus Allograft Transplant Using Three Fixation Techniques

Meniscus Allograft Transplantation With Bone Plugs Using Knotless All-Suture Anchors and Cortical Button Suspensory Fixation

Meniscus allograft transplantation can be successful for treatment of meniscal deficiency using a number of transplant techniques. In this Technical Note, we describe a double bone plug medial meniscus allograft transplantation technique that uses knotless all-suture anchors with cortical-button suspensory fixation. This technique maintains the reported advantages for bone-plug fixation while mitigating the risk for meniscal root damage, facilitating easier bone plug insertion and seating, expanding tensioning capabilities, and preventing soft-tissue irritation from suture knot stacks.

Biomechanical Analysis Evaluating Meniscal Extrusion After Knotless Suture Anchor Fixation for Segmental Medial Meniscal Allograft Transplantation

Background

Segmental medial meniscal allograft transplantation (MAT) has been shown to restore knee biomechanics; however, stable fixation of the transplantation is critical to avoid extrusion and maximize healing.

Purpose

To evaluate the degree of meniscal extrusion and biomechanical function of segmental medial MAT performed with meniscocapsular sutures versus repair augmentation with knotless suture anchors.

Study Design

Controlled laboratory study.

Methods

Segmental midbody medial meniscectomy and subsequent segmental medial MAT were performed on 10 fresh-frozen cadaveric knees. The knees were then loaded in a dynamic tensile testing machine to 1000 N for 60 seconds at 0°, 30°, 60°, and 90° of flexion, and 4 conditions were tested: (1) intact, (2) segmental defect, (3) inside-out segmental repair, and (4) anchor plus inside-out segmental repair of the medial MAT. Meniscal extrusion was measured using high-fidelity ultrasound imaging. The mean contact area and the mean and peak contact pressures were assessed with submeniscal pressure-mapping sensors. Data from testing conditions were compared with 2-way repeated-measures analysis of variance, with pairwise comparison using the Bonferroni method.

Results

At 90° of flexion, the segmental defect state showed a higher degree of meniscal extrusion compared with all other states (P ≤ .012). There was no difference in the degree of meniscal extrusion between the intact state and the inside-out repair or anchor plus inside-out segmental repair states at all knee flexion angles (P > .05). There was no significant difference in the mean and peak contact pressures among the 4 states at all flexion angles except that at 0° of knee flexion there was significantly lower peak contact pressure at the medial compartment after anchor plus inside-out segmental repair compared with the segmental defect state (P = .048).

Conclusion

Meniscal extrusion was not significantly increased at any flexion angle after segmental resection. The addition of knotless anchors did not improve meniscal extrusion or contact pressures/area compared with capsular repair alone. The addition of knotless anchors did improve contact mechanics from the segmental defect state, but only at 0° of flexion.

Clinical Relevance

The addition of knotless suture anchors to segmental meniscal transplantation increased stabilization of the meniscus at full extension compared with repair with sutures alone. This increased stabilization may lead to better long-term outcomes.

Meniscus Allograft Transplantation Augmented With Autologous Bone Marrow Aspirate Concentrate

Meniscus allograft transplantation (MAT) has been shown to be a feasible surgical option for younger patients, below 50 years of age who have meniscal insufficiency and have failed conservative treatment measures. In this technical note, we describe a procedure of harvesting and injecting bone marrow aspirate concentrate in a meniscus allograft during a MAT procedure, which may allow for longer lasting transplants and improve patient outcomes. In this technical note, bone marrow aspirate concentrate is harvested arthroscopically from the intercondylar notch at the surgical site, which prevents additional donor site morbidity, as seen with harvesting from other locations, such as the iliac crest. This also reduces operating time, since harvesting from the iliac crest requires different patient positioning and usually additional anesthesia. The authors of this surgical technique believe that biological augmentation during MATs will assist surgeons in maximizing graft survivorship and, ultimately, lead to better patient outcomes.

Segmental Medial Meniscus Transplantation in Combination With BMAC (Bone Marrow Aspirate Concentrate) Injection to Improve Healing and Prevent Extrusion

In recent years, the lack of permanent protection of meniscus scaffold applications in partial and segmental loss of meniscus tissue and the low rates of long-term survival of meniscus transplantation have brought partial meniscus transplantation applications into question. This technique aims to accelerate the capsular healing and prevent future extrusion of the segmental piece by performing biological augmentation with bone marrow aspirate concentrate together with a stable fixation of the partial meniscus allograft.