Intertrochanteric Fractures

Historical Background

Intertrochanteric femur fractures have been managed traditionally with compression hip screws (also referred to as sliding hip screws ) that allow collapse of the fracture along the axis of the lag screw, thereby creating bone-to-bone contact that, in turn, increases stability and leads to reliable healing. The widespread adoption of the compression hip screw that occurred during the 1980s dramatically reduced the incidence of nonunion and loss of fixation that occurred with earlier fixed-angle devices. In the 1990s, cephalomedullary nails were introduced for use in intertrochanteric fractures, yet their role in the management of these fractures is still somewhat controversial. Intramedullary devices offer a potentially less invasive approach to fixation of intertrochanteric fractures compared with plate fixation with a compression hip screw. Recent investigations of the functional outcomes of elderly patients with unstable fracture patterns have highlighted problems associated with loss of reduction due to collapse that, in turn, causes limb shortening and loss of the abductor moment arm with potential pain, limp, and poor functional outcomes ( Fig. 44.2 ). Fracture collapse after initial reduction and fixation is less common when intramedullary devices are used. Thus, cephalomedullary nails are now commonly used in patients with unstable fracture patterns, such as those with loss of integrity of the lateral wall of the greater trochanter and reverse-obliquity fractures. However, large series of patients comparing compression hip screws with intramedullary nails demonstrate that patients treated with intramedullary nails have a higher overall rate of revision surgery during the first year. For these reasons, the compression hip screw remains the implant of choice at many centers for the treatment of intertrochanteric fractures.

Current Surgical Practice

Surgery is the standard of care for intertrochanteric fractures. Surgical options include external fixation, internal fixation with a compression hip screw with or without a trochanteric side plate, and internal fixation with an intramedullary device, typically a so-called cephalomedullary nail (sometimes referred to as an intramedullary hip screw ). Any of these options can be considered for almost any fracture, and the optimum implant for a given fracture type is a matter of considerable debate.

External fixation is not commonly done, despite reports of success. Very few orthopedic surgeons have experience in the management of intertrochanteric fractures with external fixation. In addition, the need for prolonged care of external fixation pins, as well as complications of pin infection and later fracture through pin sites, makes this technique unpopular.

Compression hip screws represent the traditional standard for operative care of intertrochanteric femur fractures. Loss of fixation is rare when the lag screw is placed within the center of the femoral head, as noted by Kyle and associates and more recently quantified by Baumgaertner and colleagues as the so-called tip-apex distance (TAD). Although compression hip screws can be used successfully with any fracture of the proximal femur, recent evidence suggests that use of these devices in specific unstable fracture patterns may lead to increased collapse and/or loss of fixation. Traditionally, loss of the posteromedial buttress of the proximal femur, including the posterior aspect of the femoral neck and lesser trochanter, has been considered the hallmark of instability ( Fig. 44.3 ). Kyle and coworkers documented that collapse, cutout, and nonunion occurred in 25% of patients with a combined intertrochanteric-femoral neck fracture, which they described in their article for the first time. This particular type of fracture, which they described as the Kyle type V fracture, has severe comminution of the greater trochanter and associated femoral neck fracture (see Fig. 44.1 ), which led to complete collapse of the sliding hip screw in nearly half of the cases in their series and in 100% of failed cases. Other authors have highlighted loss of the integrity of the lateral wall of the greater trochanter as a risk factor for loss of reduction with compression hip screws (see Fig. 44.2 , middle panel ). Another fracture pattern that is widely considered to be a contraindication for the use of a compression hip screw is the reverse-oblique fracture ( Fig. 44.4 ). The general consensus, supported by the literature, is that the stabilization of unstable and reverse-oblique fractures via the use of a compression hip screw without addition of a trochanteric side plate leads to frequent complications ( Fig. 44.5 ). These unstable fracture patterns must be recognized because recent literature has documented shortening of the femoral neck, loss of the abductor moment arm, limb length discrepancy, and, most important, poorer functional outcomes in patients with unstable fractures treated with compression hip screws. Thus, routine use of compression hip screws in unstable fracture patterns, such as those with loss of the lateral buttress, is now discouraged unless it is combined with a trochanteric side plate to prevent excessive shortening.

Intramedullary implants, such as the cephalomedullary nail, are being used increasingly for intertrochanteric fractures ( Fig. 44.6 ). Cephalomedullary nails are available in both short and long versions. Short intramedullary devices have been plagued by intraoperative and postoperative fractures. In contrast, long cephalomedullary nails have been associated with anterior femoral cortical perforation due to mismatch between the radius of curvature of these nails and the femur. This is more of an issue when most of the femoral canal is intact, as is the case when nails are used for very proximal femoral fractures. Intramedullary nails have theoretical benefits. First, their intramedullary position buttresses the proximal femur, thereby preventing excessive collapse of the femoral neck and preventing shortening. Second, by virtue of the more medial position, they experience less loading because of a shorter moment arm. However, as was pointed out by Zlowodzki and associates, this is true only for 135-degree compression hip screws; a high-angle (150-degree) hip screw actually has a shorter moment arm than a 135-degree intramedullary hip screw. In addition, neck shaft angles of intramedullary nails are usually limited to a few angles (typically 125 or 130 degrees) that are “built in,” and the position of the guide pin is determined by the position of the nail in the femur, so that achieving the ideal center-center position of the lag screw within the femoral head is potentially more difficult to attain with these devices. This is especially true in patients with a neck shaft angle less than 125 degrees, in whom a sliding hip screw would allow better implant placement within the femoral head.

Another important difference between compression hip screws and cephalomedullary nails is their relative cost. Nails may cost three to four times more than a standard compression hip screw. This fact must be considered in light of evidence that overall outcomes remain good in patients treated with the less expensive compression hip screws and that overall revision surgery rates at 1 year may be higher in patients treated with nails.

Evidence-Based Approach to Choice of Fixation

The decision regarding choice of a compression hip screw or a cephalomedullary nail for a given patient is complex and depends on many factors related to the patient, fracture, surgeon, and environment in which care is provided. Therefore, it is worthwhile to develop an evidence-based approach to the care of these injuries.

A number of level I and II prospective clinical trials have been published that compare compression hip screws with intramedullary devices. Although a detailed analysis of all of these studies is beyond the scope of this chapter, they can be summarized as follows ( Table 44.1 ). In general, no consistent, statistically significant, and clinically relevant differences have been found among any perioperative factors between groups of patients treated with a compression hip screw or a cephalomedullary nail. In contrast, functional differences, when present, seem to be of a larger magnitude and favor intramedullary devices, especially in unstable fracture patterns. Finally, distinct differences in complications are evident, with femoral shaft fracture complicating many reported series of cephalomedullary nails, whereas loss of reduction and implant cutout are more common following use of a compression hip screw, especially in unstable fractures characterized by loss of integrity of the lateral wall of the greater trochanter, associated femoral neck fracture, or extension in the subtrochanteric region of the femur.