Outcome of primary cemented bipolar hemiarthroplasty in older patients with unstable hip fracture: A prospective study

Introduction

The intertrochanteric fracture is one of the most common fractures around the hip in older patients.^[1],[2] It constitutes up to 48% of all hip fractures and expected to increase due to the aging of population.^[3] Usually, it results from low-energy trauma in most patients.^[1]

The management of unstable intertrochanteric fractures in older patients is a challenge. Mainly due to the difficulty in obtaining anatomical reduction and the commonly associated comorbidities that lead to higher rates of morbidity and mortality.^[4]

The treatment of choice of unstable intertrochanteric fractures in older patients for several decades has been internal fixation. Many studies have shown mechanical and technical failures of this type of treatment.^[5],[6],[7]

Treatment with primary cemented bipolar hemiarthroplasty could speed up the return of activity of these cases to their preinjury level and reducing the postoperative morbidity caused by immobilization or fixation failure.^[8]

This study aims to evaluate the clinical and functional outcomes of primary cemented-hemiarthroplasty in older patients with unstable intertrochanteric fracture.

Materials and Methods

We prospectively followed 60 patients from January 2014 to February 2016 who were treated with primary cemented bipolar hemiarthroplasty - which has an additional artificial joint between the two components of the prosthesis - for unstable intertrochanteric fracture. We used total coverage sample during the study.

The inclusion criteria were patients above 65-year-old with unstable intertrochanteric fractures (highly comminuted with loss of posteromedial buttress and/or reverse oblique or subtrochanteric extension). The exclusion criteria were stable fractures and pathological fracture.

They were treated by the same orthopedic surgeon in the same hospital as soon as the condition of the patient was stabilized, usually within 72 h (average 34 ± 2.9 h) after their admission. Structured data sheet used to report demographic data. Fracture type was classified according to Kyle classification.^[9] All patients received 1.5 g of cefuroxime at the time of induction of anesthesia and continued twice a day intravenously for 48-h postoperatively as prophylaxis. In addition, they received 4000 IU of low molecular weight heparin for 4 weeks' postoperatively. We reported the perioperative parameters including duration of surgery, weight-bearing status, duration of admission, time to full weight bearing, and clinical complications. The postoperative interval of follow-up was at 2, 6, and 12 weeks and at the final follow-up (mean 13.66 ± 5.9 months). The functional outcome was assessed by Harris Hip Score (HHS) at 3 months and at the final follow-up.

Surgical procedure

In the lateral decubitus position, surgery was done through a Hardinge approach. The comminuted proximal femoral fragments were removed. The greater trochanter with abductor attachment was preserved and reattached with cerclage wire through drilling holes to the bone after canal preparation, without complications, and with good union during the follow-up period. Bone cement applied using finger packing, then bipolar prosthesis was applied. The implant used was the Link SP II hip prosthesis produced by Waldemar Link-Hamburg [Figure - 1] and [Figure - 2].

Figure 1: Preoperative X-ray of 76-year-old man with an unstable comminuted hip fracture

Figure 2: Postoperative X-ray after reconstruction with cemented bipolar

Data analysis

The collected data were analyzed with the Statistical Package for Social Sciences version 21 (IBM, Armonk, NY, USA).

Results

We recruited 60 patients in this study. Their demographic and clinical data were shown in [Table - 1]. Patients were followed for 18 months with the mean follow-up time of 13.66 ± 5.9 months [Table - 1].

Table 1: Main demographic and clinical data

Fifty-six patients (93.3%) were operated in <2 h with a mean operative time of 109 ± 7.2 min. Mobilization in bed was done for all patients on the same day of operation; 93.3% started partial weight bearing on the 1^st postoperative day; and at the end of the 1^st week, 85.2% started full weight bearing.

Majority of patients (93.3%) were hospitalized for <1 week. The mean HHS at 12 weeks' postoperatively was 77.85 ± 8.9.

At the final follow-up, 10 (16.7%) of the 60 patients had died and 2 (3.3%) were lost to follow-up. Two patients died due to pulmonary embolism, one after 6 weeks and the other one after 12 weeks' postoperatively; one patient died due to sepsis after 6 weeks' postoperatively. For the rest, the cause of death was unknown and occurred after 12 months' postoperatively. Considering complications; 3 (5%) patients had infections; two had a deep infection (deep to superficial fascia) necessitated removal of implants, one managed with resection arthroplasty, the other one was revised later with 2^nd stage after exclusion of infection. The third one had superficial infection managed with debridement and intravenous antibiotics. The isolated organism in all was Staphylococcus aureus. Two (3.3%) patients were complicated with deep venous thrombosis (DVT) and 5 (8.3%) patients had bedsores, but three of them had bedsores before the operation. We had only one (1.7%) patient with hip dislocation due to dashboard injury, which was reduced surgically. The mean HHS at the time of final follow-up was 91.14 ± 5.7. Majority of the patients (96.7%) had a pain-free mobile hip with an adequate amount of flexion, abduction, and rotation. The reoperation rate was 5% (three cases) [Table - 2].

Table 2: Clinical and mechanical complications in the study group

Discussion

Many older patients with unstable intertrochanteric hip fractures have osteoporosis. These fractures in older patients are usually associated with severe displacement and comminution. Thus, anatomical reduction of these fractures is difficult to obtain and maintain, often ending with malunion, nonunion, or reduction failure.^[10] Internal fixation greatly reduced the mortality associated with intertrochanteric fractures in the older patients^[11] but with a high failure rate due to poor bone quality, which is secondary to age-related osteoporosis.^[12] To reduce the complications associated with internal fixation, many authors have recommended prosthetic replacement for the treatment of unstable intertrochanteric fractures with improved outcome.^{[13],[14],[15],[16],[17],[18],[19],[20]} In addition, hip replacement is usually the salvage procedure in elderly patients after failure of internal fixation of intertrochanteric fractures.^[12],[17] A good outcome is expected in most patients with improved function and good pain relief after the replacement.^[17]

In this study, which included 60 patients all underwent primary cemented bipolar hemiarthroplasty for the treatment of unstable intertrochanteric fractures, the mean age of our patients was 76.15 years, which is similar to Sancheti et al. and Sinno et al. studies^[21],[22] About 62% of our patients were females, this is comparable to Sinno et al.^[22] study (68.6%). The majority of our cases (51.3%) were type 4 according to Kyle classification, unlike Rodop et al.^[19] study where the majority were type 3. As in all other studies,^{[13],[14],[15],[16],[17],[18],[19],[20],[21],[22]} simple domestic fall is the main cause of fractures. Most of the cases in our study were hospitalized for <1 week and Sinno et al.^[22] reported a similar result, while in Sancheti et al.^[21] study it was about 11 days. We reported the mean operative time to be 109 ± 7.2 min, in other studies, it ranged from 71 min in Maru and Sayani study^[4] and Sancheti et al.,^[21] to 116 ± 14 min in Kumar et al.^[23] study. More than 90% of our cases started mobilization in the 1^st postoperative day, unlike Sinno et al.^[22] where only 68.6% started mobilization on the 1^st day.

Our 1-year mortality rate was 16.7%, which is slightly more than Elmorsy et al.^[24] and Grimsrud et al.^[25] who reported (12.19%) and (10.3%), respectively. We had a 5% infection rate whereas Stern^[26] reported 6.8% and Stern and Angerman^[16] reported 2.8%. Two (3.3%) patients had DVT and 5 (8.3%) cases had bed sores, two of them had bedsores preoperatively. Grimsrud et al.^[25] reported one case of DVT and two cases of bed sores postoperatively; all were nonambulant postoperatively; this shows the importance of mobility after surgery, which is one of the main aims of this treatment. Elmorsy et al.^[24] reported no DVT or bedsores.

We reported one case with a dislocation, which was reduced surgically. Elmorsy et al.^[24] and Rady et al.^[27] reported a similar result in their studies. We did not report any case of periprosthetic fracture while in Maru and Sayani^[4] and Sancheti et al.^[21] studies, they reported one case of periprosthetic fracture each.

The mean HHS at the time of final follow-up was 91.14 in our series, while Maru and Sayani^[4] reported their HHS at the final follow-up to be 84.8, Elmorsy et al.^[24] 78.19, Kumar et al.^[23] 75 and Choy et al.^[28] 80.6; this shows that we had better results in our series, possibly because of the relatively earlier intervention.

Three cases (5%) were re-operated, two for deep infection and one for reduction of a dislocation; in Elmorsy et al.^[24] series there were 4 (9.7%) cases of re-operation; one for infection, one case for subsidence, and one case for dislocation where an open reduction was done and one for acetabular wear. Rady et al.^[27] reported 2 (4.1%) cases re-operation rate; one for reduction of a dislocation and one for infection.

Our limitation is a relatively short period of follow-up and a relatively small number of patients.

Conclusions

Primary cemented bipolar hip hemiarthroplasty may offer a good option in the treatment of unstable intertrochanteric fractures in older patients. The early mobilization and decreased complications are the most important advantages of this approach. A comparative study with internal fixation group, a larger number of patients and longer duration of follow-up is recommended.

Ethical consideration

Ethical approval was obtained from the Research Ethics Committee of the Sudan Medical Specialization Board and informed consent was obtained from all participants.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patients have given their consent for their images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Author contributions

ASE conceived and designed the study, conducted research, provided and organized data. AHA and ASE collected, analyzed, and interpreted data. ASE, AHA, and YNG review the literature. ASE and YNG wrote initial and final draft of the article. EME did all surgeries, provided research material and logistic support. All authors have critically reviewed and approved the final draft and are responsible for the content and similarity index of the manuscript.