Due to severe osteoporosis and poor muscle elasticity, fractures in the elderly are generally comminuted. In addition, the elderly tends to have numerous basic diseases, and additional physical weakness. Hence, if an appropriate treatment is not designed, chances of remedying the fracture are extremely low. Therefore, elderly patients with intertrochanteric fractures are usually referred to as end-of-life fractures [7]. The core purpose of this kind of fracture treatment is to provide stable and effective bony support for the limbs, which can help the patients recover their walking ability as soon as possible. In these cases, fracture healing is not emphasized. Currently, intramedullary fixation is the preferred treatment for this kind of fracture [8-10]. Within the intramedullary fixation system, PFNA, due to its minimal invasiveness, exhibits excellent biomechanical and stable fixation outcomes, which are highly preferred in case of osteoporotic unstable intertrochanteric fractures [11]. However, in case of the 31-A (2.2-2.3) type elderly patients with intertrochanteric fractures, bone fragments at the greater and lesser trochanters cause destruction and loss of important mechanical bone structures, thus affecting anti-pressure, tension, rotation and inversion at the femoral trochanter. Maintenance of the main fracture blocks via internal fixation alone cannot meet the corresponding mechanical requirements. Furthermore, it is difficult to reduce the fracture during the operation and, in case of severe osteoporosis, the chances of nail loosening and cutting out is markedly elevated [12-14]. Prior reports suggested that the failure rate of a femoral proximal intramedullary nail in treating intertrochanteric fractures is between 7.1-12.5% [15, 16]. Patients with unstable intertrochanteric fractures treated with PFNA need to walk without weight bearing in the early postoperative period. The upper limb strength of the elderly is weak and it is difficult to walk even with the help of double crutches or walking aids. Moreover, the potential fear of internal fixation loosening leads to the tendency of long-term bed rest, which increases the probability of bed-related complications. Thus, PFNA cannot achieve the core purpose of this kind of fracture treatment [3, 17]. In contrast, CBH can quickly provide appropriate stability for the mechanical structures around the hip joint. Therefore, patients are able to become mobile early after operation and walk with weight using the affected limb, which, in turn, significantly improves the postoperative experience of patients and achieves the purpose of helping patients gain mobility quickly after operation [18, 19]. CBH is also highly recommended by many doctors [20-22]. Kim et al. conducted a prospective clinical trial on elderly patients with unstable intertrochanteric fractures and compared the therapeutic effect of the long-stem cementless artificial bipolar femoral head prosthesis and PFNA. They found that joint replacement could help the patients regain mobility earlier [23]. Similarly, Broos et al. reported a follow-up of 94 elderly patients treated with artificial bipolar femoral head replacement and found that the average operative time of the bipolar femoral head replacement group was shorter, the mortality was lower, and the prognosis was better [5]. Likewise, Haentjens et al. reported that patients with comminuted femoral intertrochanteric fractures and severe osteoporosis can benefit from hemiarthroplasty. Hence, CBH was recommended for elderly patients with severe osteoporosis, poor prognosis after the internal fixation, short-life expectancy and poor stability of comminuted fractures [19].
Our study retrospectively investigated the difference between CBH and PFNA in treating elderly patients with osteoporotic unstable intertrochanteric fractures. Our analysis revealed that the intraoperative and postoperative blood loss, intraoperative blood transfusions, and number of blood transfusions in the CBH group was considerably more than the PFNA group. However, there was no difference in the amount and number of postoperative blood transfusions between the two groups, indicating that the amount of blood loss and the need for blood transfusions in the CBH group was more than that of the PFNA group during the perioperative period. However, patients in the PFNA group required multiple intraoperative fluoroscopies. The number of intraoperative fluoroscopies in the PFNA group were more than that of the CBH group, and the operative time was longer than that of the CBH group. Patients in the CBH group were able to become mobile significantly faster than in the PFNA group. The types of postoperative bed-related complications were visibly different between the two groups. CBH group, for instance had 3 events, whereas the PFNA group had 10. Comparing between the long-term complications after discharge, the main complications in the CBH group were the unequal length of lower limbs, fracture nonunion, and delayed incision healing, while the main complications in the PFNA group were prosthesis loosening, refracture, and reoperation. The postoperative hip joint Harris score revealed that the CBH group score was better than the PFNA group within 6 months of operation, indicating that the CBH surgery achieves earlier joint motion function. However, there was no significant difference in the score between the two groups after 12 months, indicating that CBH and PFNA achieve similar long-term effects on joint motion function 12 months after operation. Based on the above results, the patients in the PFNA group experienced less blood loss and less blood transfusions during the perioperative period. Alternately, the patients in the CBH group experienced reduced operative time and less intraoperative fluoroscopy. Moreover, patients in the CBH group achieved early mobilization, and exhibited enhanced hip joint motion within 6 months after operation.
PFNA is a minimally invasive incision that causes less bleeding during surgery. However, based on the characteristics of repeated fluoroscopy in minimally invasive surgery, it can prolong the operative time, particularly when radiation is refused. Unstable intertrochanteric fractures with severe osteoporosis can significantly increase chances of internal fixation loosening, which is the main reason why most patients opt against walking, even after receiving medical suggestion to walk with two crutches. For unstable intertrochanteric fractures, the basic principle of the postoperative functional exercise is to conduct early out-of-bed activity as soon as possible, but the affected limb cannot bear the weight entirely. As such, the patient carries weight on one leg and walks with crutches or walking aids. Patients with weak upper limb strength or poor body balance ability, are unable to implement this exercise plan. Hence, many patients remain in bed for a long time after PFNA operation [24]. Unfortunately, this increases the probability of bed-related complications, medical costs, and prolong hospitalization days. CBH therapy can provide a stable load-bearing joint in the early postoperative period and the patients can therefore boldly walk with both lower limbs, which greatly reduces the pressure of postoperative exercise. Most of the elderly are able to get out of bed and walk autonomously with the aid of instruments. It is, however, challenging for the affected limb to gain early weight-bearing ability after CBH therapy. Firstly, enough initial stability needs to form between the prosthesis and the bone. Secondly, the reduction and fixation of greater and lesser trochanter fractures needs to be carried out. Finally, the length of lower limbs needs to be restored [25, 26]. To achieve the above three purposes, joint surgeons need to study and practice for a long time. It is difficult to obtain enough stable interface between the prosthesis and bone with conventional femoral stem prosthesis. Therefore, the lengthened anatomical handle of the medullary cavity is selected, which can achieve early stable connection by pressing the distal end coat of the stem with the distal end of the fracture and the isthmus of the medullary cavity. It has the advantage of avoiding bone contact at the fracture site whilst avoiding bone cement-induced complications [27]. However, with this procedure, many cancellous bones in the proximal femurare destroyed and intraosseous blood supply in the proximal femur are hindered to a certain extent. There also exists a certain risk of stress-induced bone resorption and fracture nonunion at a later stage. In addition, the possibility of repeat operation can greatly increase with the failure of the first operation. Meanwhile, it is crucial for the early postoperative joint movement to reset the greater and lesser trochanter fractures after the prosthetic test [28]. Studies have revealed that greater than 2 cm displacement of the greater trochanter fracture fragments can lead to an apparent abductor weakness [29]. Sound reduction and fixation of greater and lesser trochanter fractures can further induceenhanced muscle strength of the hip flexion, abduction, and external rotation, and requires joint surgeons with excellent good fracture anatomical reduction and fixation skills. Furthermore, the fracture blocks must be reduced and fixed, without excessive dissection of the muscle attachment points, and a steel wire or binding band must be employed for winding and fixation. In this study, only the greater trochanter fractures were reduced and fixed in both groups, while the lesser trochanter fractures were left untreated. The surgical incision for the lesser trochanter fracture usually cleaves off part of the external rotation muscles of the hip joint. This, in turn, can weakens the hip external rotation muscle strength post surgery. Moreover, excessive stripping of the posterior incision can raise the risk of postoperative joint dislocation. The iliopsoas muscle attached to the lesser trochanter is one of the most powerful hip flexors. The binding of the steel wire in this region usually fails to resist muscle traction, and, therefore, leads to the failure of reduction and fixation. Additionally, excessive wire binding can also affect the blood supply of the proximal femur. Interestingly, hip flexion can also be compensated by other muscles. In our study, the lesser trochanter was not reset and fixed, based on the above advantages and disadvantages. From the perspective of a comparative study, both CBH and PFNA therapies performed efficacious non-interference treatment of the lesser trochanter. Differences in other aspects can be more specifically compared under the same conditions. Finally, it is more difficult to control the lower limb length during the operation for patients with both greater and lesser trochanter fractures. Hence, the feasible procedure would be to reset and fix the greater trochanter in advance, after the placement of the femoral stem. Generally, the relative position between the rotation center of the prosthesis and the greater trochanter apex of the femur is used for the evaluation of the lower limb length [30]. An equal length of lower limbs is the premise for mobility in patients after surgery. Post operation, patients with significantly different lengths of lower limbs often encounter an inferior walking experience.
To remain objective in our analysis, we successfully eliminated bias due to deep vein thrombosis, joint infection and death within 2 years of operation. Patients with deep venous thrombosis are unable to continue with the functional exercise due to the requirement of immobilizing the affected limb, as part of thrombolysis or filter implantation therapy. Patients with joint infection require multiple surgical debridement and lavage. Moreover, the bacteria and inflammatory granulation tissue often generates scars around the joint, further reducing joint function. The above two complications can ultimately lead to a significant rise in hospitalization days, cost of operation, bleeding, blood transfusions, and postoperative rehabilitation. As a result, the exercise plan would be blocked, which would negatively impact the overall research data. Lastly, in case of a patient death within 2 years of surgery, the hip joint function could not be fully evaluated, resulting in a decline in research data quality. Based on the above considerations, the above adverse factors were eliminated from our study.
There were certain limitations in our retrospective study. Firstly, the number of cases in this study was insufficient and unequal in both groups. Also, the difference in postoperative complications was not statistically significant in our analysis, which is inconsistent with the research conclusions of other scholars. Secondly, the follow-up time was limited, only 2 years. Hence, a long-term evaluation of postoperative complications like osteonecrosis of the femoral head, joint prosthesis wear, and traumatic arthritis, were not statistically analyzed.