Novel technique for repairing posterior medial meniscus root tears using porcine knees and biomechanical study

Abstract

Transtibial pullout suture (TPS) repair of posterior medial meniscus root (PMMR) tears was shown to achieve good clinical outcomes. The purpose of this study was to compare biomechanically, a novel technique designed to repair PMMR tears using tendon graft (TG) and conventional TPS repair. Twelve porcine tibiae (n = 6 each) TG group: flexor digitorum profundus tendon was passed through an incision in the root area, created 5 mm postero-medially along the edge of the attachment area. TPS group: a modified Mason-Allen suture was created using no. 2 FiberWire. The tendon grafts and sutures were threaded through the bone tunnel and then fixed to the anterolateral cortex of the tibia. The two groups underwent cyclic loading followed by a load-to-failure test. Displacements of the constructs after 100, 500, and 1000 loading cycles, and the maximum load, stiffness, and elongation at failure were recorded. The TG technique had significantly lower elongation and higher stiffness compared with the TPS. The maximum load of the TG group was significantly lower than that of the TPS group. Failure modes for all specimens were caused by the suture or graft cutting through the meniscus. Lesser elongation and higher stiffness of the constructs in TG technique over those in the standard TPS technique might be beneficial for postoperative biological healing between the meniscus and tibial plateau. However, a slower rehabilitation program might be necessary due to its relatively lower maximum failure load.

Development of a pre-clinical experimental simulation model of the natural porcine knee with appropriate ligamentous constraints

“…Porcine knees were chosen because their joint size, joint loading, cartilage and trabecular bone thickness more closely match the human condition than alternative animal models [22]. Due to this anatomical similarity, the porcine knee model has previously been widely used in studying human knee joint disease such as ligament disorders [23, 24] and new treatments such as a novel meniscus repair technique [25]. Since our study was focused on methodology development, using a porcine knee model was an important step prior to investigating a human knee model.…”

Editorial Commentary: Save the Meniscal Root, Why Not?

“…24 This study suggested that a root ligament reconstruction with an autologous graft may be an interesting approach. 25,26 Wu et al 27 reported that autologous graft reconstruction exhibits lower elongation, higher stiffness, and lower maximum failure load than the modified Mason-Allen repair. However, I have several concerns about the root reconstruction for degenerative tissue: The relatively thick tendon grafts can cause meniscal damage or result in an unfavorably elongated or truncated reconstructed root.…”

Assessment of Surrogate Models for Research on Resistance and Deformation of Repairs of the Human Meniscal Roots: Porcine or Older Human Models?

“…Some research studies have subjected sutured meniscal horn specimens to in vitro tests to evaluate the performance of surgical suture materials [14][15][16][17], the effectiveness of suture techniques [12,[18][19][20][21], the validity of suturing or fixation devices [21][22][23][24], and the suitability of surgical approaches [18,[25][26][27]. Both the resistance of the meniscal horn to suture traction without tear initiation and deformation at the suture area are assessed in these studies.…”

“…Porcine models are often chosen in experimental constructs [12,[15][16][17][18][19]21,23,[26][27][28][29]] because of their reduced variability and their similarities with human menisci in terms of anatomical structure, vascularity, volume, and weight, although the width of porcine menisci is greater [30]. In addition, the kinematics of the porcine knee reasonably approximates that of the human knee.…”