A newly-developed guide can create tibial tunnel at an optimal position during medial meniscus posterior root repairs.

BACKGROUND: During transtibial pullout repair of medial meniscus (MM) posterior root tears (MMPRTs), accurate tibial tunnel creation within the anatomic MM posterior root attachment seems critical. This study aimed to evaluate the tibial tunnel position created by a newly-developed Precision guide during pullout repair of MMPRTs. METHODS: In 40 patients who underwent transtibial pullout repairs, the tibial tunnel was created using the Unicorn Meniscal Root (UMR) (n = 20) or Precision guide (n = 20). Three-dimensional computed tomography images of the tibial surface were evaluated postoperatively, using Tsukada's measurement method. The expected anatomic center of the MM posterior root attachment was defined as the center of three tangential lines corresponding to anatomic bony landmarks. The expected anatomic center (AC) and the tibial tunnel center (TC) were evaluated using the percentage-based posterolateral location on the tibial surface. The difference in the mediolateral and anteroposterior percentage distance between the AC and TC was calculated, as was the absolute distance between the AC and TC. RESULTS: The mean AC was located 77.4% posterior and 40.1% lateral. The mean TC was similar in the UMR and Precision guide groups. There was no significant difference in the mediolateral percentage distance (UMR 3.9% vs. Precision 3.6%, p = 0.405), but a significant difference was observed in the anteroposterior percentage distance (UMR 3.5% vs. Precision 2.6%, p = 0.031). The mean absolute distance between the AC and TC was 3.9 mm and 3.5 mm (UMR and Precision guide groups, respectively) (p = 0.364). CONCLUSIONS: The new Precision guide can create tibial tunnel in an optimal and stable position during pullout repair of MMPRTs.

Intraarticular lengths of double-bundle grafts can change during knee flexion: Intraoperative measurements in anatomic anterior cruciate ligament reconstructions.

BACKGROUND: The lengths of the anteromedial bundle (AMB) and posterolateral bundle (PLB) change during knee motion in double-bundle anterior cruciate ligament (ACL) reconstruction. However, the actual intraarticular graft length would be affected by the bone tunnel position and tunnel creation angle during ACL reconstruction. The aim of this study was to investigate the intraarticular length change of the AMB and PLB in patients who underwent anatomic double-bundle ACL reconstruction. HYPOTHESIS: We hypothesized that the PLB would show a more dynamic length change pattern than the AMB during knee flexion at ACL reconstruction. METHODS: Thirty-two patients (16 men and 16 women) who had isolated ACL injuries with intact menisci were investigated. Anatomic double-bundle ACL reconstructions were performed using semitendinosus tendon autografts at a mean age of 30.6 years. The graft and tunnel lengths were measured intraoperatively. Intraarticular graft lengths and length changes were calculated at 0° and 90° of knee flexion during ACL reconstruction. Intraoperative data were collected prospectively, and analyses were performed retrospectively. RESULTS: The intraarticular length of the AMB at 0° of knee flexion was 28.1±5.5mm. At 90° of knee flexion, the AMB intraarticular length decreased to 25.6±4.8mm. The intraarticular length of the PLB decreased to 17.7±4.6mm at 90° of knee flexion compared to 22.0±4.2mm at 0° of knee flexion. Changes in the intraarticular graft length during knee flexion were detected more in the PLB (4.1mm) than in the AMB (2.0mm, p=0.01). DISCUSSION: This study demonstrated that the intraarticular length change of the PLB during knee motion was larger than that of the AMB in anatomic double-bundle ACL reconstructions with semitendinosus tendon autografts and suspensory femoral fixation devices. LEVEL OF EVIDENCE: IV; retrospective cohort study.

Steep medial tibial slope and prolonged delay to surgery are associated with bilateral medial meniscus posterior root tear.

PURPOSE: Contralateral medial meniscus posterior root tear (MMPRT) can sometimes occur after primary surgeries for MMPRT and lead to unsatisfactory outcomes. The incidence rate and risk factors for contralateral MMPRT have not been well investigated, despite their clinical importance. Therefore, the incidence and predictors of bilateral MMPRT were aimed to be evaluated. METHODS: Fourteen patients with bilateral MMPRT (group B) and 169 patients with unilateral MMPRT (group U) were enrolled in this study. Sex, age, body mass index, time between injury and surgery, and medial tibial slope angle (MTSA) were compared between the groups. MTSA was measured using lateral radiographs. RESULTS: The incidence rate of bilateral MMPRT was 6.2% among all patients with MMPRTs. Multivariate logistic regression analysis showed that a prolonged time between injury and surgery (odds ratio [OR], 1.0; 95% confidence interval [CI] 1.00-1.01; P < 0.05) and steeper MTSA (OR, 1.85; 95% CI 1.21-2.64; P < 0.01) were significantly associated with the development of bilateral MMPRT. Receiver operating characteristic curve analysis showed that MTSA > 10.0° was associated with bilateral MMPRT, with a sensitivity of 93% and specificity of 69%. CONCLUSION: A longer time between injury and surgery and steeper MTSA were risk factors for the development of bilateral MMPRT. Surgeons need to pay close attention to the contralateral knee in addition to the primary injured knees when treating knees with steep MTSA. Besides, early meniscal repair of primary MMPRT would be important to prevent the events of contralateral MMPRT. LEVEL OF EVIDENCE: III.

Pullout repair using modified Mason-Allen suture induces better meniscal healing and superior clinical outcomes: A comparison between two surgical methods.

BACKGROUND: Pullout repairs of medial meniscus posterior root tears (MMPRTs) have many surgical options. However, there has been no reliable clinical study conducted to compare the superiority of each pullout repair technique. The current study hypothesized that pullout repairs using a modified Mason-Allen suture with FasT-Fix (F-MMA) would have several advantages in postoperative clinical outcomes and meniscal healing compared with single FasT-Fix. The aim of this study was to investigate the clinical usefulness of these two techniques in treating MMPRTs. METHODS: Thirty-eight patients who had complete MMPRTs were included. All patients underwent transtibial pullout repairs. To compare the clinical usefulness between pullout repairs using single FasT-Fix and F-MMA techniques, patients were divided into two groups. Second-look arthroscopic evaluations of meniscal healing were performed at one year postoperatively. Clinical outcomes were assessed using: Lysholm and visual analogue scale (VAS) pain scores, and Knee Injury and Osteoarthritis Outcome Score (KOOS). RESULTS: Single FasT-Fix and F-MMA pullout repairs improved clinical outcomes in patients with MMPRTs. At second-look arthroscopy, VAS pain, KOOS pain, and arthroscopic meniscal healing scores following F-MMA pullout repairs were superior to those after single FasT-Fix pullout repairs. CONCLUSIONS: This study demonstrated that F-MMA suture configuration obtained better meniscal healing and superior clinical outcomes compared with single FasT-Fix repairs in patients with MMPRTs. These results suggest that the F-MMA pullout repair may possibly reduce knee pain in arthroscopic treatments of MMPRTs.