Introduction
Fracture of the proximal femur, generally termed “hip fracture,” is one of the most common and severe fractures occurring in the elderly population. It has been reported that 90 % of hip fractures occur in patients over the age of 65 [
1]. When compared with other fractures in this population, hip fracture has greater associated rates of death and disability as well as higher medical expenses [
1,
2]. During the last 25 years, the incidence of hip fracture has increased rapidly, and it is estimated that 7.3–21.3 million individuals will suffer from this injury globally in 2050 [
3,
4]. Therefore, the treatment and management of hip fracture pose great challenges for clinicians in osteology and surgery.
The primary goal for the treatment of intertrochanteric hip fracture is to achieve minimal mortality and morbidity, low re-operation rates, and early successful run-up to sustainable mobility. The basic strategy for achieving this goal greatly depends on the quality of fracture fixation, including biomechanical stability and rigidity [
5,
6]. Currently, the sliding hip screw is the most widely used implant for fixation of intertrochanteric hip fracture and thus serves as a benchmark in this field [
7]. In elderly patients, however, this surgical procedure is always associated with substantial intra- and perioperative blood loss and severe soft-tissue damage [
8,
9]. Therefore, minimally invasive surgical techniques are being developed in order to overcome these problems implicit in sliding-screw fixations [
9]. The percutaneous compression plate (PCCP) and proximal femoral nail anti-rotation (PFNA) are recently developed devices designed for minimally invasive surgery in the treatment of hip fractures, and they have been widely used in elderly patients with demonstrated clinical effectiveness [
10‐
12]. Researchers have also performed numerous clinical studies to compare either the PCCP or PFNA with other orthopedic implants [
13‐
16]. Nevertheless, reports on the clinical effectiveness of the PCCP versus PFNA in elderly patients with intertrochanteric fractures are quite few.
In order to compare the clinical effects of the PCCP versus PFNA in the treatment of hip fractures in elderly patients, we conducted a prospective randomized study from January 2008 to October 2011 involving 90 elderly patients with intertrochanteric fractures who underwent minimally invasive surgery using the PCCP or PFNA. Evaluation variables, including operation time and intra- and perioperative blood loss, incidence of postoperative complications, and final clinical outcomes at the end of follow-up, were used to compare the benefits of these two implants.
Discussion
The treatment of femoral intertrochanteric fracture in elderly patients remains challenging because these patients always have severe comorbidities, resulting in long hospitalizations and multiple postoperative complications with a high mortality rate [
18,
19]. Therefore, internal fixation is usually recommended in the clinic in order to reduce mortality as well as the incidence of coxa vara and limb shortening [
25]. Traditional internal fixation has many disadvantages, such as a large wound, heavy blood loss, severe pain, a high incidence of postoperative complications, and slow functional recovery [
26,
27]. Minimally invasive surgical techniques for hip fracture are able to overcome these drawbacks. The PCCP and PFNA, the minimally invasive implants most frequently used for internal fixation in current traumatic orthopedics, have been widely accepted for use in the treatment of femoral intertrochanteric fracture in elderly cases [
8,
9]. To our knowledge, however, there has been no literature published regarding the comparison between these two implants. In this study, the results showed that there was no obvious difference in the clinical outcomes of patients receiving PCCP and PFNA, except for the surgery duration and intra- and perioperative blood loss.
A percutaneous compression plate was first reported for clinical application by Gotfried in 2000 [
18]. This implant is a device with a double-axis and two parallel femoral neck screws, which can withstand high rotational force and provide rotational stability. The small diameter of the screw protects the lateral cortex, thus effectively preventing fracture displacement and allowing immediate full weight-bearing [
28]. Comparatively, PFNA has a special helical blade design, which is developed on the basis of the proximal femoral nail (PFN). This special blade has a large surface and increasing core diameter, which guarantees maximum compaction and optimal hold in the bone. Increased rotational and angular stability caused by bone compaction around the PFNA blade can effectively avoid rotation and varus collapse, which has been biomechanically proven [
29]. Therefore, generally, both the PCCP and PFNA have desirable mechanical properties for internal fixation of hip fractures. However, in regards to surgical duration and intra- and perioperative blood loss, our results showed there was a significant difference between these two implants. Patients in the PFNA group underwent longer operation times and lost more blood during surgery compared to the PCCP group. This might be attributed to the procedures necessary for femur opening and insertion of the PFNA implant into the medullary canal, which requires much care and time to succeed in correctly positioning the implant in the medullary canal.
Our clinical outcome results showed that postoperative complications were well controlled in both groups and that there was no significant difference in the incidence of postoperative complications between PCCP and PFNA. Furthermore, we did not observe any complications related to fracture union during the follow-up period, which can perhaps be attributed to the extensive experience of the surgeons involved in this study as well as strict postoperative patient management. These findings are also consistent with the results reported in previous studies [
16,
30], which report a very low incidence of complications related to fracture union in patients receiving the PCCP or PFNA. Nevertheless, one patient with the PFNA did encounter femoral shaft fracture at the tip of the implant. This complication has been reported to be common when using intramedullary nails for treating proximal femoral fractures. Leung et al. [
31] reported a geometric distinction in Gamma nails used in Chinese patients because elderly Chinese have relatively shorter femurs and excessive anterior bowing as compared to American and European patients. The case of femoral shaft fracture in our study also involved a short femur. When the PFNA implant was inserted, the stem likely did not fit the patient’s femur well, thus causing the malposition of the implant in the medullary canal. Additionally, a wedge effect may occur during the introduction process involving the use of a hammer. The malpositioning of the PFNA and the wedge effect produced a stress concentration, thus resulting in the occurrence of femoral shaft fracture in this case.
It should be noted that two patients in the PFNA group developed FES right after surgery. The pathophysiology of FES remains unclear, although two theories, mechanical and biochemical, currently exist, which postulate its occurrence [
32]. Previous literature has pointed out that FES is commonly associated with traumatic fracture of the femur, pelvis, or tibia [
33]. In addition, there may be a casual correlation between FES onset and intramedullary nailing, and pelvic and knee arthroplasty, although there is much controversy surrounding this issue [
32]. In the current study, FES only occurred in the patients receiving PFNA, indicating intramedullary fixation with PFNA might be responsible for its onset. However, further study with a large population is needed to verify this assumption.
Researchers have reported that hip and thigh pain is common, with treatment involving intramedullary fixation [
34]. However, our results show that the incidence of hip and thigh pain was relatively lower in both groups when compared with the results reported in previous literature [
34]. As to the recovery of hip function and walking ability, there was no significant difference between these two devices. Between both groups, walking ability was recovered to pre-injury status in 58.9 % of patients, which is close to or even higher than the results reported in other literature [
34,
35]. This finding indicates that the selection of the PCCP or PFNA as the implant for fixation is not a key determinant of clinical outcomes. General conditions of patients, postoperative exercises, and the multidisciplinary management of preoperative comorbidities and postoperative complications may determine the final outcomes of patients.
Numerous studies have been performed to compare the clinical effect and safety of the PCCP with the dynamic hip screw (DHS), which has been considered as the gold standard treatment for intertrochanteric fracture [
26]. As a minimally invasive implant, the PCCP has obvious advantages in regards to blood loss, need for transfusions, and systematic complications, although it was shown to be similar to the DHS in mechanical stability and clinical effect [
8,
9]. Furthermore, increasingly surgeons are not considering the PFNA a truly minimally invasive technique because of the potential risk of femoral shaft fracture, more severe tissue damage, and greater blood loss [
6]. According to our experience, although the PFNA has the aforementioned disadvantages, they can be easily controlled. Additionally, this device has a broader range of applications than PCCP. For example, it can be used for treating 31A3 fractures, which is a contraindication for the PCCP. More importantly, insertion of the PFNA is able to compact the cancellous bone, providing additional anchoring, which is especially suitable for patients with osteoporotic bone.
In summary, based on our findings, the PCCP and PFNA appeared to have similar clinical effects in treating elderly patients with intertrochanteric fractures. The PCCP was shown to require shorter operation times and less blood loss than the PFNA. However, both were demonstrated to be ideal implants for the treatment of femoral intertrochanteric fractures, especially those that occur in elderly patients with severe pre-existing diseases.