[Morphology character and reduction methods of sagittally unstable intertrochanteric fractures]

To investigate the morphology character of sagittally unstable intertrochanteric fractures and reduction methods.

A retrospective study was used to analyze the clinical data of sagittally unstable intertrochanteric fractures cases, which were treated with proximal femoral nail anti-rotation (PFNA) fixation from March 2009 to June 2016. In the study, 36 cases were followed up completely, in which 17 cases accepted open reduction, and the other 19 cases accepted minimally invasive reduction. The operation time, amount of bleeding, the fluoroscopy times, postoperative radiographic measurements, such as tip-apex distance (TAD) and sliding distance of the spiral screw, and hip Harris scores were analyzed. The morphology character of the fractures was documented and investigated.

The average follow-up time was 15 months. The amount of bleeding of the open reduction group was (170.5±19.7) mL, and the amount of bleeding of the minimally invasive group was (54.7±12.5) mL. The amount of bleeding of the minimally invasive group was significantly less than that of the open reduction group (P<0.001). Between the two groups, there were no significant differences in other evaluation parameter, including operation time (P=0.054), the fluoroscopy times (P=0.053), fracture healing time (P=0.305), postoperative radiographic measurements, such as TAD (P=0.317) and sliding distance of the spiral screw (P=0.206), and hip Harris scores (P=0.459). In regard to morphology character of the fractures, the proximal anterior unstable fractures with separation displacement were more common than the proximal posterior unstable fractures with impaction. The characteristic feature of the proximal anterior unstable fractures was the proximal anterior and medial long oblique fracture, and a V shape cortical defect in the distal fracture fragment on the externally rotation X-ray.

Sagittally unstable intertrochanteric fractures can be divided into the proximal anterior unstable fractures with separation displacement, and the proximal posterior unstable fractures with impaction. The two types have their own morphology character individually. The reduction should be performed by minimally invasive techniques.