IMHS and ENDOVIS BA Nails: A Study of Comparison in Trauma Surgery

Research Article

Austin J Emergency & Crit Care Med. 2019; 5(1): 1067.

IMHS and ENDOVIS BA Nails: A Study of Comparison in Trauma Surgery

Bernardino S*

Department of Orthopaedic and Trauma Surgery, Viale Regina Margherita, 74 70022, Altamura Bari, Italy

*Corresponding author: Saccomanni Bernardino, Department of Orthopaedic and Trauma Surgery, Viale Regina Margherita, 74 70022, Altamura Bari, Italy

Received: July 26, 2019; Accepted: August 27, 2019; Published: September 03, 2019


Intertrochanteric fractures are surgically treated by using different methods and implants. The optional type of surgical stabilization is still under debate. However, between devices with the same philosophy, different design characteristics may substantially influence fracture healing. This is a prospective study comparing the complication and final functional outcome of two intramedullary devices, the Intramedullary Hip Screw (IMHS) and the ENDOVIS BA nail. Two hundred fifteen patients were randomized on admission in two treatment groups. Epidemiology features and functional status was similar between two treatment groups. Fracture stability was assessed according to the Evan's classification. One hundred ten patients were treated with IMHS and 105 with ENDOVIS BA nail. There were no significant statistical differences between the two groups regarding blood loss, transfusion requirements and mortality rate. In contrast, the number of total complications was significantly higher in the ENDOVIS BA nail group. Moreover, the overall functional and walking competence was superior in the patients treated with the IMHS nail. These results indicate that the choice of the proper implant plays probably an important role in the final outcome of surgical treatment of intertrochanteric fractures. IMHS nail allows for accurate surgical technique, for both static and dynamic compression and high rotational stability. IMHS nail proved more reliable in our study regarding nail insertion and overall uncomplicated outcome.

Keywords: IMHS; ENDOVIS BA; Study of comparison


Pertrochanteric fractures constitute one of the commonest fractures of the hip. They mainly occur in elderly people due to osteoporosis. Their incidence will probably continue to increase in the near future because of population aging [1,2]. The goal of treatment is fracture reduction and stable osteosynthesis to allow immediate mobilization. For many years, the sliding hip screw and plate had been the gold standard in treating pertrochanteric fractures [3-5]. Nowadays, there is an increasing interest in intramedullary nailing, especially for the unstable pertrochanteric fractures. There are several studies comparing intramedullary hip screw (IMHS, Smith & Nephew) to other intramedullary devices or sliding hip screw [6-8]. No data are available in the literature about the ENDOVIS (Citieffe) nail. No study has prospectively compared the IMHS to the ENDOVIS BA nail, specifically in the unstable fracture patterns. This is a prospective randomized study in order to compare the clinical results of these two intramedullary devices, which have different design characteristics.

Patients and Methods

Between July 2004 and June 2007, 261 nonconsecutive patients who sustained a pertrochanteric fracture were operated. Inclusion criteria for the study were patients over 60 years old with a pertrochanteric fracture after a fall that was considered low energy injury. Forty-six patients with pathologic fractures, or a high-energy injury and patients under 60 years old were excluded. In 110 patients it was used the IMHS and in 105 the ENDOVIS BA nail. The patients were randomly dispersed to one of the two treatment options by the use of sealed envelopes containing cards, indicating the treatment for each patient. Fracture stability was assessed according to the Evan's classification as modified by Jensen [9,10]. Prophylactic intravenous second generation cephalosporin was administered before operation and discontinued 48 hours postoperatively. Patients were mobilized on second post-operative day, allowing them to bear weight as much as they could tolerate. All cases received anticoagulant prophylactic therapy with low molecular weight heparin, starting on admission and for 4 weeks postoperatively. Data recorded in all patients and included the type of the fracture, the preoperative blood hemoglobin level and walking ability before fracture (Table 2). The operative data were surgical time, blood loss and any intraoperative complication. Postoperatively, the level of hemoglobin was recorded on the first postoperative day, the mobility status at the time of discharge, the duration of hospital stay and the mortality rate at 12 months. The patients were evaluated for their functional status and by serial plain radiographs at 1, 3, 6 and 12 months after operation. Fracture healing was judged based on increased sclerosis and obliteration of fracture lines. X-rays interpreted in association with clinical data and more specifically by the elimination of pain during weight bearing. In order to estimate the functional outcome the Parker-Palmer mobility score was used [11].

Implant Description

IMHS features a cannulated intramedullary nail with a 4 degrees Medio lateral bend to allow for insertion through the greater trochanter. The nail is used with a standard AMBI/CLASSIC lag screw, compression screw and 4.5mm locking screws. A sleeve, which is held by a set screw, passes through the nail and over the lag screw. The sleeve helps prevent rotation, while allowing the lag screw to slide. Standard IMHS is available in two angles (130-135 degrees), in four distal diameters (10, 12, 14, 16 mm) with a proximal diameter of 17.5mm. Its length is 21cm. ENDOVIS BA is made of titanium alloy with a cervico-diaphyseal angle 130 degrees, a metaphyseal angle 5 degrees and total length 195mm. The diameter proximally is 13mm and distally 10mm. There are two holes for cephalic screw insertion and one for the distal screw. The cephalic screws are available in nine length sizes, 7.5mm diameter, self-drilling and self-taping. The distal screw is available in four sizes, 5mm diameter, self-drilling and selftaping. The distal tip of the nail has a diapason section. Operations were performed on a fracture table under spinal anesthesia and image intensifier control. After closed reduction of the fracture, a longitudinal incision started proximal to the greater trochanter apex and extended proximally about 4-10 cm, depending on the size or obesity of each patient. After splitting the aponeurosis, the entry point was made just on the tip of the greater trochanter. The nail was inserted into the femur diaphysis without reaming. Our goal was to insert the hip screw under the midline of the femoral neck, advancing the tip of the screw close to the subarticular surface of the femoral head. Tip to Apex Distance (TAD) was measured from the tip of the guide wire. When TAD value was less than 25mm, we proceeded to reaming and insertion of the cephalic screw. Fluoroscopic control was performed to ensure that joint line was not penetrated after screw placement. Distal locking was made preferably with 2 screws.

Statistical Analysis

All data were recorded and statistically analyzed. Pearson chisquare test, Fisher's exact test and Student t-test were performed to discriminate differences between the 2 groups. Significance levels were set at P ‹ 0.05. All tests were calculated using the SPSS, version 13.0 (SPSS Inc., Chicago, IL, USA) statistic package for personal computers.


In the IMHS treatment group, 34 were men and 76 women. In the ENDOVIS group, there were 33 men and 72 women. The mean age was 83.5 years (range 69-95 years) in the IMHS group and 83.9 years (range 71-96 years) in the ENDOVIS BA group. Thirty seven fractures was graded as stable and 73 as unstable for the IMHS while 39 as stable and 66 as unstable fractures for the ENDOVIS BA group (Table 1). The mean time needed for the two intramedullary nails procedures was 25.4 minutes (range 17-45 min) in IMHS group and 24.8 minutes (range 21-51 min) in ENDOVIS BA group. As expected, there were no significant statistically differences between the two groups regarding blood loss and transfusion requirements (Table 3). In IMHS group 35 (31.8%) patients achieved independent walking, 57 (51.8%) patients needed a walking aid and 18 (16.4%) were not able to ambulate. The corresponding values in the ENDOVIS BA group were 28 (26.7%), 48 (45.7%), 29 (27.6%) (Table 4). The mean preoperative Parker-Palmer mobility score was 7.27 for IMHS group and 7.23 for ENDOVIS BA group. The mean postoperative Parker- Palmer mobility score was 6.4 for IMHS and 4.7 for ENDOVIS BA. Statistical analysis between the 2-treatment group’s revealed significant difference, favoring the IMHS treated patients (Chi-square test, p ‹ 0.05) (Table 4). Two patients from the IMHS group and three from the ENDOVIS BA died during the hospital stay. The overall mortality rates at one year were 15.45% and 15.23% respectively with no statistical difference observed between the two study groups.