Injuries of the meniscal attachments can lead to meniscal extrusion. We hypothesized that the extent of lateral meniscal extrusion (LME) was associated with the severity of the lateral meniscus posterior root tear (LMPRT). This study aimed to evaluate the relationship between preoperative LME and arthroscopic findings of LMPRT in knees with anterior cruciate ligament (ACL) injury. Thirty-four knees that had LMPRTs with concomitant ACL injuries on arthroscopy were evaluated. Patients were divided into two groups, partial and complete root tears, via arthroscopic findings at the time of ACL reconstruction. We retrospectively measured preoperative LMEs using magnetic resonance imaging (MRI). Statistical analysis was performed using the Mann-Whitney U-test and Chi-square test.Purpose
Methods
Meniscus repair can restore the function of torn meniscus in anterior cruciate ligament (ACL)-reconstructed knees. However, few reports investigate the relationship between concurrent meniscus repair with ACL reconstruction and postoperative meniscal position. This study aimed to evaluate the size of the medial meniscus in patients who underwent ACL reconstruction and concomitant all-inside medial meniscus repair. This study received the approval of our Institutional Review Board. Twenty patients underwent ACL reconstruction and concurrent medial meniscus repair of a peripheral longitudinal tear using the FasT-Fix meniscal repair device. Medial tibial plateau length (MTPL) and width (MTPW) were determined by radiographic images. We evaluated the Lysholm score, anteroposterior instability (difference in KT-2000 arthrometer measurement), meniscal healing, and magnetic resonance imaging (MRI)-based medial meniscal length (MML) and width (MMW). The healing status of repaired medial meniscus was assessed by 2nd-look arthroscopy.Background
Methods
Hyaluronan (HA) promotes extracellular matrix (ECM) production and inhibits the activity of matrix degrading enzymes in chondrocytes. The meniscus is composed of the avascular inner and vascular outer regions. Inner meniscus cells have a chondrocytic phenotype compared with outer meniscus cells. In this study, we examined the effect of HA on chondrocytic gene expression in human meniscus cells. Human meniscus cells were prepared from macroscopically intact lateral meniscus. Inner and outer meniscus cells were obtained from the inner and outer halves of the meniscus. The proliferative activity of meniscus cells was evaluated by WST-1 assay in the presence or absence of HA (MW = 600–1200 kDa; Seikagaku). Gene expression of SOX9, COL2A1, and COL1A1 was assessed by a quantitative real-time PCR analysis. The effect of HA on the gene expression and cellular proliferation was investigated under the treatment of interleukin (IL)-1α. Meniscal samples perforated by a 2-mm-diameter punch were maintained for 3 weeks in HA-supplemented media. Cultured meniscal samples were evaluated by histological analyses.Background
Methods
One of the complications occurring after total knee arthroplasty (TKA) is venous thromboembolism (VTE). The current screening techniques for VTE are venography, lower extremity vascular ultrasound, pulmonary scintigraphy, and contrast-enhanced computed tomography (CT). Although venography and lower extremity vascular ultrasound can detect deep venous thrombosis (DVT) in the lower extremities, pulmonary thrombosis poses a diagnostic problem. We performed contrast-enhanced CT screening for DVT and pulmonary embolism (PE) after TKA, and assessed the efficacy of the following prophylactics for VTE: fondaparinux, enoxaparin, and edoxaban. Subjects included 219 patients (260 knees) undergoing TKA at our hospital between April 2007 and November 2012. The 260 subject knees were divided as follows: group C, 31 cases in which DVT prophylactics were not used (April 2007 to October 2008); group F, 107 cases receiving fondaparinux 2.5 mg/day (July 2007 to October 2009); group ENO, 87 cases receiving enoxaparin 2000–4000 IU/day (November 2009 to October 2011); and group EDO, 35 cases receiving edoxaban 15–30 mg/day (November 2011 to November 2012). Contrast-enhanced CT images were obtained from the pulmonary apex to the foot for diagnosis of VTE. Groups were compared for incidence of symptomatic PE, asymptomatic PE, DVT-negative asymptomatic PE, DVT-positive asymptomatic PE, and DVT.Introduction:
Materials and Methods:
In Japan, edoxaban has been used for the prevention of venous thromboembolism (VTE) after total knee arthroplasty (TKA) since June 2011. Edoxaban is an oral direct factor Xa inhibitor, expected to be more convenient for the postoperative treatment of TKA. Enoxaparin, a II and Xa inhibitor, was approved in Japan for the prevention of VTE in patients undergoing orthopedics surgery from 2008. In this study, the effect for the prevention of VTE after TKA was compared between these two drugs in Japanese patients. We studied 42 Japanese patients who underwent TKA from May 2011 to April 2012. The operations were performed under general anesthesia, continuous femoral nerve block, an air tourniquet, and using cements for implant fixation. These patients were divided in two groups, use of 30 mg edoxaban once daily (ED group), and use of 1000 IU of enoxaparin twice daily (EN group). The initial dose was administered between 12 and 21 hours after surgery. We compared the incidence of VTE, bleeding complications, D dimer levels, and hemoglobin (Hb) loss. The screening of VTE was performed by enhanced CT scan screening from the chest to the foot on postoperative day 5 or 6 in all patients. The bleeding complication was divided into major bleeding and minor bleeding with Japanese guideline for the prevention of VTE. D dimer levels and Hb levels were preoperatively and postoperative day 1, 3, 5, 7, and 14. The loss of Hb was calculated from preoperative Hb level minus lowest postoperative Hb level.Introduction
Patients and Methods
Computer navigation system has been reported as a useful tool to obtain the proper alignment of lower leg and precise implantation in TKA. This system alsoãζζhas shown the accurate gap balancing which was lead to implants longevity and optimal knee function. The aim of this study was determine that the postoperative acquired deep knee flexion would be influenced by intraoperative kinematics on navigated TKA even under anesthesia. Forty knees from 40 patients, who underwent primary TKA (P.F.C. sigma RPF, DePuy Orhopaedic International, Leed, UK) with computer-navigation system (Ci Knee, BrainLAB / DePuy Inc, Leeds, UK), were recruited in this study. These patients were classified into two groups according to the recorded value of maximum knee flexion at three month after surgery: 15 patients who obtained more than 130 degrees of flexion in Group A, and 25 patients less than 130 degrees in Group B. We retrospectively reviewed about intraoperative kinematics in each group, to obtain the clue for post operative deep-flexion. The measurements of intraoperative kinematics were consisted of 3 points: femoral rotation angle (degree) and antero-posterior translation (mm), which were measured as the translation of the lowest points of femoral component to tibial cutting surface, and the joint gap difference between the medial and lateral components gap (mm). All joint kinematic data were recorded at every 10 degrees of flexion from maximum extension to flexion under anesthesia.Purpose
Materials & methods
