Comparison of two simple stitches and modified Mason-Allen suture for medial meniscus posterior root tear based on the progression of meniscal posterior extrusion: A retrospective cohort study

Purpose: Medial meniscus (MM) posterior root (PR) tear leads to severe MM posterior extrusion (PE), resulting in rapid knee cartilage degeneration. MMPR repairs are recommended to reduce MMPE, especially during knee flexion. However, the difference in MMPE between different repair techniques remains unknown. This study aimed to investigate preoperative and postoperative MMPE following several pullout repair techniques. We hypothesized that a technique using two simple stitches (TSS) would be more useful than FasT-Fix-dependent modified Mason-Allen suture (F-MMA) to prevent the progression of MMPE in knee extension. Methods: This retrospective study included 35 patients who underwent MMPR repair. To compare MMPE, patients were divided into two groups according to the use of F-MMA while grasping the posterior capsule and TSS without grasping it. Open magnetic resonance imaging was performed at 10° and 90° knee flexion preoperatively, and at 3 and 12 months postoperatively, and the MMPE of both groups was evaluated. Results: A significant difference was observed between preoperative and 3-month postoperative MMPE at 90° knee flexion in both groups ( p < .01). A significant difference was observed in 3- and 12-month postoperative MMPE at 10° knee flexion between both groups ( p = .04/.02), whereas no significant difference in the preoperative MMPE at 10° knee flexion was observed between them ( p = .45). Conclusions: Both repairs were found to be useful to reduce MMPE in knee flexion. Further, F-MMA repair increased MMPE in knee extension, unlike TSS repair. These findings suggest that TSS might have more advantages for load distribution when standing or walking.

Mild to Moderate Varus Alignment in Relation to Surgical Repair of a Medial Meniscus Root Tear: A Matched-Cohort Controlled Study With 2 Years of Follow-up

Background: Increased varus alignment of the lower extremity is known to be a poor prognostic factor for the surgical repair for a medial meniscus root tear (MMRT). However, given the concept of constitutional varus, which is present in a substantial portion of the normal population, the generally accepted surgical indication for MMRT concerning a varus alignment of 5° may be unnecessarily narrow. Purpose: To compare the surgical outcomes of arthroscopic transtibial pullout repair of MMRT according to the degree of varus alignment of the lower extremity. Study Design: Cohort study; Level of evidence, 3 Methods: Patients who underwent isolated arthroscopic transtibial pullout repair of MMRT between January 2010 and July 2017 at one institution and had a minimum follow-up of 2 years were included in this study. Patients were classified into 1 of 2 groups: the experimental group (n = 22) included patients with a preoperative hip-knee-ankle angle between 5° and 10° varus (mild to moderate varus alignment) and the control group (n = 51) included those with a preoperative hip-knee-ankle angle <5° varus (neutral alignment). Clinical scores and radiographic parameters were compared between the groups to assess surgical outcomes, which were statistically matched for potential confounders (age, body mass index, the severity of cartilage lesion) by use of the inverse probability of treatment weighting. A noninferiority trial was performed comparing the experimental and control groups in terms of subjective outcomes (International Knee Documentation Committee subjective and Lysholm scores) and objective outcomes (postoperative medial meniscal extrusion and the rate of osteoarthritis progression). Results: There were no statistically significant differences in surgical outcomes between the groups in subjective and objective aspects, which were consistent before and after inverse probability of treatment weighting. Apart from the clinical improvement observed in both groups, overall degenerative changes in the knee were found, although progression rates did not differ between the groups. In terms of the noninferiority trial, the overall surgical outcomes in the experimental group were not inferior to those in the control group. Conclusion: The short-term surgical outcomes of arthroscopic transtibial pullout repair for MMRT of patients with mild to moderate varus alignment were not inferior to but rather comparable with those with neutral alignment in terms of subjective and objective aspects. Therefore, it would be inappropriate to exclude patients with a diagnosis of MMRT from being indicated for the surgery simply because of mild to moderate varus alignment.

Biomechanical Comparisons of Anterior Cruciate Ligament Avulsion Fracture Fixation Using High-Strength Suture and Ultra-High Molecular Weight Polyethylene Suture Tape in a Porcine Model

A wide variety of fixation methods have been reported to fix anterior cruciate ligament (ACL) tibial avulsion fractures, but there have been no studies into the fixation of these fractures with ultra-high molecular weight polyethylene (UHMWPE) suture tape as an alternative to conventional thread. Type III ACL tibial avulsion fractures were created in 20 skeletally immature porcine knees. All specimens were randomized into two treatment groups: (1) pullout repair using no. 2 suture fixation and (2) pullout repair using UHMWPE suture tape fixation. The specimens were tested cyclically (20 cycles, 0–40 N, 100 mm/min) in the direction of the native ACL and loaded to failure (100 mm/min) on a tensile tester. Statistically significant differences between the structural properties (displacement, upper yield load, maximum load, linear stiffness, and elongation at failure) under cyclic loading and single-cycle loading were analyzed. Displacement during cyclic testing was 1.56 ± 1.03 mm in the UltraBraid group and 0.99 ± 0.48 mm in the SUTURETAPE group, with no significant differences found between the groups (p = 0.13). There were no significant differences in upper yield load (161.9 ± 68.9 N in the UltraBraid group, 210.4 ± 60.1 N in the SUTURETAPE group, p = 0.11), linear stiffness (14.7 ± 4.7N/mm in the UltraBraid group, 18.1 ± 7.9 N/mm in the SUTURETAPE group, p = 0.27), or elongation at failure (20.1 ± 8.0 mm in the UltraBraid group, 21.5 ± 7.2 mm in the SUTURETAPE group, p = 0.69). On the other hand, significant differences were observed in maximum load in the SUTURETAPE group (219.7 ± 89.2 N in the UltraBraid group, 319.3 ± 92.6 N in the SUTURETAPE group, p = 0.025).

Functional, Magnetic Resonance Imaging, and Second-Look Arthroscopic Outcomes After Pullout Repair for Avulsion Tears of the Posterior Lateral Meniscus Root

Background: Little data exist in the literature regarding second-look arthroscopic outcomes after pullout repair for avulsion tears of the posterior lateral meniscus root. Purpose: To (1) assess the functional, magnetic resonance imaging (MRI), and second-look arthroscopic outcomes after pullout repair for avulsion tears of the posterior lateral meniscus root; (2) determine which demographic and clinical factors influenced healing of the repaired posterior lateral meniscus root; and (3) compare outcomes between different meniscal healing status groups. Study Design: Case series; Level of evidence, 4. Methods: A total of 31 patients underwent pullout repair for avulsion tears of the posterior lateral meniscus root and had a minimum 2-year follow-up. Functional outcomes were assessed using patient-reported scores (Lysholm, Tegner, and International Knee Documentation Committee [IKDC] scores). Lateral meniscal extrusion, cartilage degeneration of the lateral compartment, and healing of the repaired posterior lateral meniscus root were assessed via MRI. The healing status was also assessed using second-look arthroscopic surgery, and the patients were divided into different healing status groups. Results: The postoperative patient-reported scores improved significantly compared with the preoperative values ( P = .001). Lateral meniscal extrusion was reduced significantly from 3.37 ± 0.82 mm preoperatively to 0.63 ± 0.80 mm at final follow-up ( P = .001). The grade of cartilage degeneration of the lateral compartment progressed from 0.69 ± 0.67 preoperatively to 0.95 ± 0.83 at final follow-up ( P = .213). MRI scans showed complete healing in 28 patients (90.3%) and partial healing in 3 patients (9.7%). Second-look arthroscopic surgery showed stable healing in 18 of 23 patients (78.3%) and lax healing in 5 of 23 patients (21.7%). Patients with stable healing had significantly higher Lysholm and IKDC scores, more reduction of meniscal extrusion, and less progression of cartilage degeneration than did patients with lax healing ( P < .05). Concomitant anterior cruciate ligament reconstruction was found to significantly positively influence healing of the repaired posterior lateral meniscus root ( P = .047). Conclusion: Pullout repair for avulsion tears of the posterior lateral meniscus root yielded significantly improved patient-reported scores, reduced meniscal extrusion, and a satisfactory healing rate at final follow-up. Patients with stable healing had significantly better functional and MRI outcomes than did patients with lax healing.