Anterior High-Intensity Zone in Lumbar Discs: Prevalence and Association with Low Back Pain.

OBJECTIVES: To explore the features of high-intensity zone (HIZ) in anterior annulus fibrosus and assess the association of anterior HIZ with low back pain (LBP). DESIGN, SETTING, AND SUBJECTS: A retrospective study of 5,940 discs in 1,188 individuals was conducted. METHODS: Subjects' information and LBP symptoms confirmed by an orthopedic surgeon were acquired from the medical record. Magnetic resonance (MR) image reading and analysis were performed by two experienced blinded radiologists. RESULTS: Two hundred eighty individuals exhibited 355 anterior HIZs in 355 discs. The prevalence was 23.57%; 88.45% were located in the inferior part of the annulus fibrosus. It frequently occurred in the middle and upper segments of lumbar spine, especially at L3/4 (45.63%). Of the 355 anterior HIZs, only 79 (22.25%) were consecutive-slides HIZ. Round type (63.38%) was the most common shape of anterior HIZs. The highest prevalence was found in individuals aged 60-69 years. LBP was confirmed in 141 anterior-HIZ individuals. The incidence of LBP in anterior-HIZ individuals was significantly higher than in non-HIZ subjects (50.36% vs 35.24%, χ2 = 18.314, P < 0.001). CONCLUSIONS: Anterior HIZ is a lower-prevalence, age-related sign on lumbar MR images. The spatial distribution of anterior HIZ can be distinguished from posterior HIZ. The number of consecutive anterior HIZ slides might suggest fewer Dallas grade 4 anterior annular disruptions in this sample. Anterior HIZ was correlated with LBP.

Dynamic Fixation versus Static Fixation in Treatment Effectiveness and Safety for Distal Tibiofibular Syndesmosis Injuries: A Systematic Review and Meta-Analysis.

To compare the effectiveness and safety of dynamic fixation (DF) and static fixation (SF) in distal tibiofibular syndesmosis injuries (DTSI) by a system review and meta-analysis. PubMed, Cochrane, and EMBASE were systematically searched by computer to select clinical randomized controlled trials (RCT) and cohort trials comparing DF and SF in treating patients with DTSI. RCT and cohort trials comparing DF and SF for patients with DTSI were included. Inclusion criteria: (i) prospective or retrospective study of patients with DTSI; (ii) patients were diagnosed as having DTSI by imageology and only received DF treatment or SF treatment; (iii) the study compared DF and SF in DTSI; and (iv) one or more of the following outcomes were reported: ankle joint functional score, surgical complications, malreduction of syndesmosis, and second operations. Exclusion criteria: (i) non-human studies; (ii) DTSI patients accompanied with other complications or other joints injuries; and (iii) full text unavailable. RevMan V5.3 software was used to perform the statistical analysis. Outcomes analyzed by Revman software showed that there were no statistically significant differences between DF and SF in the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score (MD, 1.90; 95% CI, -0.23 to 4.03; P = 0.08; I2 = 0%), Olerud-Molander (OM) score (MD, 1.92; 95% CI, -7.96 to 11.81; P = 0.70; I2 = 55%), incidence of syndesmotic malreduction (RR, 0.19; 95% CI, 0.03 to 1.09; P = 0.06; I2 = 0%), and overall postoperative complication rate (RR, 0.30; 95% CI, 0.09 to 0.99; P = 0.05, I2 = 75%) and the rate of second procedure was significantly lower with DF (RR, 0.17; 95% CI, 0.07 to 0.43; P = 0.0002, I2 = 54%). Compared to SF, DF has an advantage, with a low rate of second procedures to treat DTSI.