ABSTRACT
Background@#Stenotic femoral intercondylar notch is considered as a risk factor for anterior cruciate ligament (ACL) injury and three-dimensional notch volume is used as a marker for the injury. The primary purpose of this study was to assess the difference in notch volume between the ACL-injured and uninjured in men and women combined or stratified by sex. The secondary purpose was to assess the difference in notch volume between the ACL-intact men and women. @*Methods@#A search of PubMed/Medline, Scopus, Google Scholar, and Cochrane databases from inception to December 9, 2020, was conducted without restrictions using the following terms: ACL, notch, volume, notch volume, femoral notch volume, and intercondylar notch volume. Studies that compared the ACL-injured with uninjured controls were included. Independent extraction of articles by two authors using predefined data fields including study quality indicators was done. All pooled analyses were based on the inverse-variance weighted random effects model and mean difference was chosen as the effect measure. @*Results@#Nine studies (1,169 knees) qualified for overall analysis (both sexes combined) and significant heterogeneity was observed, which disappeared after pooling studies with age-sex matched controls and those without. Notch volume in the ACLinjured was 0.75 cm3 (95% confidence interval [CI], 0.53–0.96 cm3 ), which was smaller than that in the age- and sex-matched controls. Six studies qualified for analysis in men. Notch volume in the ACL-injured men was smaller, especially when non-contact ACL injury was considered (1.40 cm3 ; 95% CI, 1.08–1.73 cm3 ). Five studies qualified for analysis in women and ACL-injured women had smaller notch volume irrespective of the mechanism of injury (0.38 cm3 ; 95% CI, 0.18–0.59 cm3 ). Notch volume of the uninjured men was larger than that of the uninjured women (1.86 cm3 ; 95% CI, 1.54–2.18 cm3 ). @*Conclusions@#ACL-injured adults have smaller notch volume than the age- and sex-matched controls. Non-contact ACL-injured males have smaller notch volume compared to ACL-intact males. ACL-injured females have smaller notch volume irrespective of the nature of injury. Men have higher notch volume than women. The quality of evidence is very low to low.
ABSTRACT
Since Boehler's sentinel description, a universally acceptable thoracolumber fracture classification has eluded spine surgeons. The concept of the stability of a thoracolumbar injury changed continuously from the two column concept of Holdsworth to the three column theory of Denis. With the advent of sophisticated imaging techniques, improved biomechanical understanding, and in order to meet the high expectations of patients, several classification systems have been forwarded by the stalwarts in the field. Each successive system has contributed significantly to the understanding and prediction of treatment outcome. Load sharing classification by McCormack attempted to rationalize the use of short segment posterior instrumentation. Magerl et al. developed a comprehensive classification system based on progressive morphological damage determined by three fundamental forces: compression, distraction, and axial torque. Vaccaro et al. devised the thoracolumbar injury severity score based on three independent variables: the morphology of the injury, posterior ligamentous complex (PLC) integrity, and neurological status at the time of injury. But, there are limitations to the classification system, especially when magnetic resonance imaging yields a PLC status as indeterminant. In the absence of a universally acceptable classification system, it is important to understand the underlying concepts of the fractures. The author concisely reviews the subject from its inception in the year 1929 to the present day.