A total of 144 males and 204 females (n = 348) with intertrochanteric fractures were included in this study, with a mean age of 73.5 years (Table 1). No patients were allocated to the isolated posteromedial group or posterior + posteromedial group. Instead, we found that almost all patients had medial wall injuries (339/348, 97.41%). Of all of the patients, 213 (61.21%) were allocated to the posterolateral + posteromedial + medial group, and we further divided them into the posterolateral + posteromedial + isolated fragment medial group and the posterolateral + posteromedial + simple medial group. Furthermore, 111 (31.9%) and 102 (29.3%) patients were in the posterolateral + posteromedial + isolated fragment medial group and posterolateral + posteromedial + simple medial group, respectively, and 81 (23.3%), 33 (9.5%), 12 (3.4%), and 9 (2.6%) in the posterolateral + medial group, the isolated medial group, the posteromedial + medial group, and isolated posterolateral group, respectively (Figure 4).
Posterolateral + Posteromedial + Isolated Fragment Medial Group (Type I):
In total, 111 fractures were included in this group for analysis. This group of patients had the most serious fracture displacement, including 66 patients with the posteromedial wall fractured into three fragments (posterolateral fragments (greater trochanteric region), posterior-medial fragments (lesser trochanteric region), and medial fragments (medial wall)) (Figure 6A). The pattern of fractures in the other 33 patients was posteromedial separation into two fragments, which may be posterior (posteromedial + posterolateral) and medial fragments, or posteromedial + medial fragments and posterolateral fragments. There were also 12 patients whose fractures were severely displaced with extremely small fragments, and could not be systematically classified.
Posterolateral + Posteromedial + Simple Medial Group (Type II):
Among the 102 fractures in this group, the most common feature was the presence of a posteromedial intact fragment (77 patients in total) including posterolateral + posteromedial + medial involvement (Figure 6B). Moreover, 2 posterior-medial fragments (a posterolateral fragment and a medial + posteromedial intact fragment) was observed in 24 patients, with few patients found to have a posterior-medial fracture line located between the posterolateral and posteromedial sides.
Posterior Lateral + Medial Group (Type III):
Overall, 81 fractures were analyzed. The fracture characteristics of this group were as follows: the greater trochanter fragment at the posterolateral side and the fracture fragment at the medial wall (Figure 6C). The fracture line at the medial wall was found to be an extension of the fracture line at the anterolateral wall. Moreover, the position of the fracture line at the medial wall was significantly higher than that of type I and type II(P<0.01), and the smaller trochanter was bypassed, so that the smaller trochanter could remain intact. This group of fractures can sometimes form isolated medial fragments, but in this group of patients, the shape of the posteromedial small area remained intact without fracture line extension.
Isolated Medial Group (Type IV):
Thirty-three fractures were analyzed, and the common fracture features in this group of patients were that the fracture line of their medial wall was an extension of the fracture line of the anterolateral wall (Figure 6D), which could be seen extending to the base of the femoral neck on the posterior side, and retaining the intact femoral calcar. Of the 30 patients, only 3 patients endured a medial wall isolated fragment separated from the anterolateral wall.
Posteromedial + Medial Group (Type V):
We analyzed 12 fractures in this group. The fracture characteristics of this group of patients were that the fracture line interrupted when the anterolateral wall extended to the posteromedial wall, which formed a complete isolated fragment posteromedially and medially (Figure 6E). Otherwise, the posteromedial and medial separation of two isolated fragments was observed in 12 patients.
Isolated Posterolateral Group (Type VI):
The group exhibited 9 fractures, of which patients had a relatively typical greater trochanter fracture (Figure 6F). All patients had visible injuries to the anterior wall, and the fracture was a separate fragment at the greater trochanter. Because of the retrospective nature of the study, which collected patients undergoing surgery, conservative treatment was chosen by the majority of patients with greater trochanteric fractures such that the number of patients counted in this group may have been insufficient.
Radiography Parameters, Function, and Range of Motion:
In analyzing radiography parameters, we measured the patient’s sliding distance of cephalic nail as well as femoral neck–shaft angle(FNSA) changes. The imaging results of patients in different groups are shown in Table 2 and Figure 7. We found that the sliding distance and the change of FNSA of patients in the Type I group and the Type II group were significantly different from those of other groups, while the sliding distance and the change of FNSA in the Type VI group were significantly smaller. In addition, we found a significant difference in the change in FNSA between the Type I group and the Type II group.
The function and range of motion of different groups are presented in Table 2 and Figure 7. The HHS score of the Type I group was significantly lower than that of the other five groups, but only statistically different between type IV and VI(P<0.01).
The range of motion (external rotation and abduction of the hip joint) in patients with type I and II fractures was significantly less than that in the other three groups. The range of motion (external rotation and abduction) of the Type VI group was less than that in the other two groups, but it was not statistically significance. The postoperative flexion range of motion of patients in the Type I, Type VI, and Type V groups was significantly less than that of the other three groups, and the difference was statistically significant.