[The significance of lumbar MRI in the diagnosis of recurrented lumbar disc herniation after surgery].

OBJECTIVE: To retrospectively evaluate the clinical evaluation of preoperative lumbar T2 sagittal MRI image in predicting the recurrent lumbar disc herniation (RLDH). METHODS: Between January 2009 and April 2011, 28 patients were diagnosed as recurrent L4-5 disc herniation within 2.5 years after surgery, and 25 of them were included in the study as relapse group. At the same time, selected 25 patients implemented the same surgical methods in the same level as a control group randomly, they were all with good to excellent result and the follow-up time was at least 2.5 years. There was no statistical significance between the two groups in gender, age and body mass index(BMI) (P > 0.05). The lumbar MRI image of two groups of patients before surgery were collected and analyzed, with the disc degeneration grade classified. The χ(2) test was used to analyzed the difference of degeneration between the two groups of patients before surgery. Rank correlation analysis evaluated the correlation between disc degeneration and the period of time from the first operation to the recurrence. RESULTS: In terms of preoperative lumbar disc degeneration, there were 22 cases of low-grade disc degeneration and 3 cases of advanced disc degeneration in the relapse group and 5 cases and 20 cases respectively in the control group. there was significant difference between two groups (χ(2) = 23.27, P < 0.05), low-grade disc degeneration (gradesIand III) was significantly more frequent in the relapse group than in the control group. The patients with low-grade disc degeneration had a higher risk of recurrence, that was the risk of recurrent disc herniation increased by a factor of 4.4 from advanced disc degeneration to low-grade disc degeneration(OR = 4.4, 95%CI:1.983-9.765, P < 0.05). In cases of recurrence, the time interval between primary surgery and the recurrence of the patient with advanced disc degeneration was longer compared with low-grade disc degeneration (r = 0.733, P < 0.05). CONCLUSIONS: Preoperative lumbar MRI image may suggest the possibility of the recurrence lumbar disc herniation.Light disc degeneration is an important risk factor for recurrent disc herniation, and the time interval between primary surgery and the recurrence is positively correlated with severity of disc degeneration.

Laminar reclosure after single open-door laminoplasty using titanium miniplates versus suture anchors.

Laminar closure is associated with expansive open-door laminoplasty. Suture anchor fixation and titanium miniplate fixation are used to prevent laminar reclosure. However, few studies have compared the clinical effects of the 2 fixation methods. The authors performed a prospective study of 55 patients with cervical spondylotic myelopathy who underwent single open-door laminoplasty with suture anchor fixation (n=30) or titanium miniplate fixation (n=25) from June 2005 to May 2011. Clinical and radiologic outcomes were evaluated at 1 week and 1 year postoperatively. There were no significant differences between the 2 groups in terms of Japanese Orthopaedic Association (JOA) scores, JOA recovery rates at 1 week postoperatively, and the incidence of C5 palsy. Compared with the suture anchor group, the recovery rate in the titanium miniplate group was significantly higher at 1 year postoperatively, and the incidence of axial symptoms and mean axial symptom scores were significantly lower at 1 week, but not 1 year, postoperatively. Radiologic examination showed no significant differences in the anteroposterior diameter of the spinal cord and the vertebral body-to-spinal cord distance between the 2 groups. At 1 year postoperatively, the opening angle in the suture anchor group was significantly less than that in the titanium miniplate group. Titanium miniplate fixation is more effective than suture anchor fixation in preventing laminar closure, accompanied by a higher JOA recovery rate at 1-year follow-up and a lower incidence of axial symptoms.

[Safety and efficacy of rivaroxaban for prevention of deep vein thrombosis in patients with preoperative abnormal D-dimer after total knee arthroplasty].

OBJECTIVE: To evaluate the safety and efficacy of rivaroxaban for prevention of deep vein thrombosis (DVT) in patients with preoperative abnormal D-dimer after total knee arthroplasty (TKA). METHODS: Between August and September 2013, 60 consecutive patients with varus knee osteoarthritis undergoing unilateral TKA were enrolled in the study. According to the preoperative D-dimer level, the patients were divided into 2 groups: D-dimer normal group (control group, n = 41) and D-dimer abnormal group (test group, n = 19). No significant difference was found in gender, age, body mass index, and preoperative knee range of motion between 2 groups (P > 0.05). All patients underwent conventional primary TKA and anticoagulation therapy with rivaroxaban to prevent DVT. The tourniquet use time, postoperative hospitalization time, and total hospitalization time were compared between 2 groups. At 1, 3, and 5 days after operation, prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (FIB), and D-dimer were measured. Wound complications and DVT were observed. RESULTS: The postoperative hospitalization time of the test group was significantly longer than that of the control group (t = 2.327, P = 0.031), while the tourniquet use time and total hospitalization time showed no significant difference between 2 groups (P > 0.05). All the patients were followed up 6-8 months (mean, 7.2 months). Wound complications occurred in 3 cases (7.3%) of the control group and in 2 cases (10.5%) of the test group, showing no significant difference (χ2 = 0.175, P = 0.676). Color ultrasonography showed no pulmonary embolism and DVT at 6 weeks after TKA. There were significant differences in PT, TT, and FIB between at pre- and post-TKA in the same group, but no significant difference was found between 2 groups. The APTT and D-dimer had significant differences between at pre- and post-TKA in the same group, and between groups. There was no significant interaction effect between time and group for each index. CONCLUSION: Preoperative abnormal D-dimer level should not be regarded as a contraindication for TKA. The risks of DVT and wound complications in patients with abnormal D-dimer level are similar to patients with normal D-dimer level using rivaroxaban administration after TKA. It is unnecessary to conventional monitor D-dimer and other coagulation and hemorrhage laboratory tests in the patients after TKA.

[Imaging analysis of ossification of ligamentum flavum associated with dural adhesions].

OBJECTIVE: To summarize the characteristic imaging signs of ossification of the ligamentum flavum (OLF) associated with dural adhesions by analyzing retrospectively the imaging signs of OLF associated with dural adhesions. METHODS: A retrospective analysis was made on clinical data of 85 patients undergoing OLF surgery between January 2010 and September 2012. The patients were assigned into the study group and the control group according to the preoperative imaging signs. Of 85 patients, 34 had both "tram track sign" and "jagged line sign" as the study group and 51 had either "tram track sign" or "jagged line sign" and neither of them as the control group. Adherence between dura mater and ligamentum flavum was observed during operation as the "gold standard" for the diagnosis of dural adhesion. The imaging information of CT and MRI in sagittal and axial planes was analyzed. The typical characteristics of dural adhesions were found. Then the sensitivity, specificity, and positive likelihood ratio of the preoperative imaging examinations were calculated to estimate the reference value and diagnostic value (> 5 having reference value, and > 10 having diagnostic value). RESULTS: In the study group, dural adhesion was observed in 26 patients (10 males and 16 females), and the other 8 patients (6 males and 2 females) had no dural adhesion. In the control group, dural adhesion was found in 2 female patients who had "jagged line sign", and 49 patients had no dural adhesion (14 males and 35 females). In patients having both "tram track sign" and "jagged line sign", the sensitivity was 92.9%; the specificity was 86.0%; and the positive likelihood ratio was 6.6. In patients having "tram track sign", the sensitivity was 92.9%; the specificity was 64.9%; and the positive likelihood ratio was 2.6. In patients having "jagged line sign", the sensitivity was 100%; the specificity was 77.2%; and the positive likelihood ratio was 4.4. CONCLUSION: For patients with OLF having both "tram track sign" and "jagged line sign", preoperative CT and MRI have a reference value for diagnoses of the OLF associated with dural adhesions.