ABSTRACT
With accelerated aging process of the population, femoral intertrochanteric fractures have gradually become another major social health problem in China. Internal fixation is still the gold standard treatment for the fractures. Fracture reduction is the first step of the treatment and also the first element that affects the treatment efficacy. It is still controversial in clinical practice how to evaluate the quality of fracture reduction during internal fixation of the fractures. This article systematically expounds and analyzes the 7 systems of judging criteria for the reduction of intertrochanteric fractures from the aspects of fracture alignment, fracture apposition, difference in judgment criteria, and difference in imaging methods, in order to provide a reference for reaching consensus and improving curative effects.
ABSTRACT
Objective: To measure the rotation angle of the head-neck fragment of intertrochanteric fracture after cephalomedullary nail fixation by three-dimensional CT imaging, and to explore its clinical significance. Methods: The clinical data of 68 patients with unstable intertrochanteric fracture of AO/Orthopaedic Trauma Association (AO-OTA) type 31-A2 treated with cephalomedullary nail fixation and with complete intraoperative fluoroscopy and postoperative three-dimensional CT imaging data between July 2016 and October 2018 were retrospectively analyzed. Among them, there were 21 males and 47 females, aged 68-93 years, with an average age of 81.8 years. There were 31 cases of AO/OTA type 31-A2.2 and 37 cases of 31-A2.3. Fracture reduction quality was evaluated according to Baumgaertner et al. and Chang et al. criteria. The anteromedial cortical contact or not of each patient was observed by three-dimensional CT imaging on T3DView software after operation. The rotation of head-neck fragments were divided into three types: non-rotation, flexion rotation, and hyperextension rotation. The rotation angles of each type were measured and the relationship between the rotation type of the head-neck fragments and the contact of the anteromedial cortex was analyzed. Results: The reduction and fixation of the small trochanter were not performed in 68 patients. According to Baumgaertner et al. criteria, the quality of fracture reduction was excellent in 15 cases (22.1%), acceptable in 50 cases (73.5%), and poor in 3 cases (4.4%). According to Chang et al. criteria, 31 cases were excellent (45.6%), 33 cases were acceptable (48.5%), and 4 cases were poor (5.9%). Thirty-nine cases (57.4%) received anteromedial cortical support and 29 cases (42.6%) did not receive cortical support. Three-dimensional CT imaging showed non-rotation in 12 cases (17.6%), flexion rotation in 39 cases (57.4%), and hyperextension rotation in 17 cases (25.0%). There were 7 cases (58.3%), 30 cases (76.9%), and 2 cases (11.8%) of cortical support in non-rotation group, flexion rotation group, and hyperextension rotation group, respectively. The rotation angles were (1.05±0.61), (13.96±6.17), (8.21±3.88)°, respectively. There were significant differences between groups ( P<0.05). Conclusion: In the unstable intertrochanteric fracture after cephalomedullary nail fixation, the rotation of head-neck fragment exists in most patients, and the types of flexion rotation and non-rotation can easily obtain cortical support reduction.
ABSTRACT
Objective To compare the biomechanical stabilities among different combinations of anterior and medial cortical supports after intramedullary nailing for unstable intertrochanteric fractures.Methods Twenty-seven synthesized femur specimens were used to create models of unstable intertrochanteric fracture of type 31A2.1 according to AO/ASIF classification.They were divided into 9 groups (n =3) according to 9 combinations of anterior and medial cortical supports on the anteroposterior and lateral X-ray films:positive-positive,positive-neutral,positive-negative,neutral-positive,neutral-neutral,neutral-negative,negative-positive,negative-neutral,negative-negative groups.After all the fractures were fixated with the newly adapted femoral intertrochanteric nails (FITN),static loadings were applied for tests of fatigue and destruction to investigate the relative displacements and yield loads of the head-neck fragments.Results For the positive-positive,positive-neutral,positive-negative,neutral-positive,neutral-neutral,neutral-negative,negative-positive,negative-neutral,negative-negative groups,the vertical displacements of the head-neck fragments under fatigue loading were respectively 5.33 ±0.58 mm,7.83 ±0.29mm,7.73 ±0.15 mm,8.17 ± 0.29 mm,8.33±1.15 mm,8.83±0.29 mm,9.33±0.58 mm,9.67±1.15 mm and 12.0±1.0 mm,showing significant differences (P ＜ 0.05).The smallest displacement was observed in the positive-positive group,significantly smaller than that in any other groups (P ＜ 0.05).For the above 9 groups,the yield loads were respectively 4,967 ± 153 N,4,467 ± 58 N,3,717 ± 76 N,2,767 ± 58 N,2,533 ± 58 N,2,267 ± 58 N,1,833 ± 58 N,1,667 ± 58 N and 1,333 ± 58 N,showing significant differences between any 2 groups (P ＜ 0.05).In the destruction test,bone interface loosening in the femoral head happened in 2 cases,bone interface loosening in the intertrochanteric zone in 15 cases,split fracture at the zone of distal locking nail in 2 cases,and loosening and breakage of the internal fixator in the distal femur in 8 cases.Conclusions The medial cortical support plays a major role and the anterior cortical support plays a secondary role in the stability of unstable intertrochanteric fracture.In the surgical procedure,surgeons should avoid the medial cortical negative support as much as possible.