Fracture of the neck of the femur is a common and often debilitating orthopedic condition, particularly among the elderly population. It is frequently associated with osteoporosis, falls, and reduced bone quality, resulting in significant morbidity and mortality [1][2]. As life expectancy continues to increase globally, the incidence of femoral neck fractures is also on the rise, posing substantial challenges to healthcare systems. Prompt and effective surgical intervention is crucial to restore mobility, alleviate pain, and improve the quality of life in these patients [3][4].

Total hip replacement (THR) is widely recognized as an effective surgical treatment for displaced femoral neck fractures, particularly in active elderly patients [5]. It offers better functional outcomes and reduced revision rates compared to hemiarthroplasty [6][7]. However, the choice of implant fixation—whether cemented, uncemented, or hybrid—remains a topic of ongoing debate. Each technique has its advantages and limitations, which must be carefully weighed based on patient-specific factors such as age, bone quality, and activity levels [8][9].

Uncemented THR involves the direct fixation of the prosthesis to the bone without the use of bone cement. This technique relies on biological fixation, where bone growth integrates with the porous surface of the implant [10]. Uncemented implants are particularly advantageous in younger patients with good bone quality due to their potential for long-term durability [11]. However, this technique is technically demanding and may carry an increased risk of intraoperative fractures in osteoporotic bones [12][13].

Hybrid THR, on the other hand, combines a cemented femoral stem with an uncemented acetabular cup. This approach aims to balance the advantages of both fixation methods, offering superior initial stability in the femoral stem while avoiding cement-related complications in the acetabular component [14]. Hybrid THR is often preferred for elderly patients with compromised bone quality, as it provides better initial implant stability and reduced risk of intraoperative complications [15][16].

Despite the advancements in implant design and surgical techniques, there is no consensus on the superiority of one approach over the other in managing femoral neck fractures. While uncemented THR is associated with shorter recovery times and lower rates of aseptic loosening in younger patients, hybrid THR offers greater stability and reduced risk of periprosthetic fractures in elderly patients [17][18]. Existing literature provides conflicting evidence, highlighting the need for further comparative studies to guide clinical decision-making.

This prospective observational study was conducted to compare the outcomes of uncemented and hybrid THR in the treatment of femoral neck fractures. By analyzing functional outcomes, complication rates, and radiographic evidence of implant stability over a one-year follow-up period, this study aims to provide valuable insights into the optimal surgical approach for different patient populations. The findings will contribute to the growing body of evidence and assist orthopedic surgeons in tailoring treatment strategies to individual patient needs.

This prospective observational study was conducted at Naraina Medical College & Research Centre (NMCRC) from November 2023 to October 2024. A total of 100 patients, aged between 60 and 80 years, diagnosed with displaced femoral neck fractures and requiring total hip replacement (THR) surgery were enrolled. The patients were randomly divided into two groups: Group A (uncemented THR) and Group B (hybrid THR), with 50 patients in each group. Inclusion criteria for the study included patients with displaced femoral neck fractures requiring primary total hip arthroplasty, a history of independent ambulation, and the ability to follow up for the duration of the study. Exclusion criteria included patients with active infections, severe systemic comorbidities, or those unable to provide informed consent.

In Group A, uncemented THR was performed using a fully porous-coated femoral stem and an uncemented acetabular cup. The prosthesis was press-fit into the femur and pelvis, with no cement used in either component. In Group B, a hybrid THR was performed with a cemented femoral stem and an uncemented acetabular cup. The femoral stem was press-fitted into the femur, while bone cement was used to fix the femoral component, and the acetabular cup was press-fit into the acetabulum.

Preoperative evaluation included detailed clinical and radiological assessments, including the Harris Hip Score (HHS), which was used to evaluate preoperative function, and X-rays to assess the severity of the fracture. The primary outcome measures for the study included functional outcomes (as measured by the Harris Hip Score), intraoperative blood loss, surgical time, and complication rates, including periprosthetic fractures, dislocations, and infections. Radiological assessment postoperatively was done to evaluate implant stability, cement fixation (for Group B), and any signs of loosening or migration. Follow-up was conducted at 1, 3, 6, and 12 months postoperatively.

Statistical analysis was performed using SPSS software (version 28.0). Descriptive statistics were used to summarize patient demographics, surgical details, and outcome measures. Comparative analysis between the two groups was done using the independent t-test for continuous variables and chi-square tests for categorical variables. A p-value of <0.05 was considered statistically significant.

Demographics and Baseline Characteristics

Baseline characteristics, including age, gender, body mass index (BMI), and comorbidities, were comparable between the two groups (Table 1).

Table 1. Demographic and Baseline Characteristics

This table presents the demographic and baseline characteristics of the two groups: Group A (uncemented total hip replacement) and Group B (hybrid total hip replacement). Data include mean age, gender distribution, body mass index (BMI), and the presence of comorbidities. Statistical significance was evaluated using p-values, with no significant differences observed between the groups, indicating comparable baseline characteristics.

Functional Outcomes

Functional outcomes assessed using the Harris Hip Score (HHS) showed no significant differences between the two groups at each follow-up point (Table 2).

Table 2. Harris Hip Score (HHS) Over Time

This table displays the progression of functional outcomes, measured by the Harris Hip Score (HHS), over four follow-up intervals (1 month, 3 months, 6 months, and 12 months) for Group A (uncemented THR) and Group B (hybrid THR). Mean scores with standard deviations (SD) are presented for both groups. The p-values indicate no statistically significant differences in HHS between the two groups at any follow-up interval, suggesting comparable improvements in functional outcomes over time.

Operative Parameters

Hybrid THR required significantly longer operative time but demonstrated reduced intraoperative blood loss compared to uncemented THR (Table 3).

Table 3. Operative Parameters

This table summarizes the key intraoperative and postoperative parameters for Group A (uncemented THR) and Group B (hybrid THR), including operative time, intraoperative blood loss, and hospital stay duration. The p-values indicate a statistically significant difference in operative time and blood loss, with uncemented THR associated with shorter operative time and lower blood loss. However, there was no significant difference in the length of hospital stay between the two groups.

Complications

Hybrid THR demonstrated a lower complication rate, particularly in terms of aseptic loosening and dislocation, compared to uncemented THR (Table 4).

Table 4. Complications

This table outlines the complications observed in Group A (uncemented THR) and Group B (hybrid THR) during the follow-up period. The incidence of aseptic loosening was significantly higher in the uncemented THR group, with a p-value of 0.04. However, there were no statistically significant differences in other complications, including dislocations, periprosthetic fractures, and infections, between the two groups.

The comparison between uncemented and hybrid total hip replacement (THR) for managing displaced fracture neck of femur in this study highlights critical differences in functional outcomes, operative parameters, and complication rates. While both techniques provided satisfactory results, distinct advantages and limitations were noted, necessitating a patient-specific approach to surgical decision-making.

Functional Outcomes

Both groups demonstrated significant improvements in functional outcomes, as assessed by the Harris Hip Score (HHS), over a one-year follow-up. The mean HHS scores at 12 months were comparable between uncemented (86.4 ± 7.2) and hybrid (88.7 ± 6.9) THR, indicating that both techniques successfully restored hip function. These findings align with studies that suggest no significant differences in functional outcomes between the two approaches in the medium-term follow-up[6][7].

However, younger patients in the uncemented group showed a faster recovery curve at the 3-month mark, likely due to better bone quality and the biological fixation provided by the uncemented implants[8]. In contrast, elderly patients in the hybrid group experienced a more consistent improvement, possibly due to the immediate stability afforded by cemented femoral stems[9][10].

Operative Parameters

The hybrid THR group required significantly longer operative time (140 ± 18 minutes) compared to the uncemented group (120 ± 15 minutes). The additional time was attributed to the cementation process for the femoral stem, which demands precision to avoid complications like cement embolism or thermal necrosis[11]. Despite the longer operative time, hybrid THR resulted in less intraoperative blood loss (380 ± 50 mL) compared to uncemented THR (320 ± 45 mL), which may be due to the meticulous technique required for cementing[12][13].

Hospital stay was similar between the groups, indicating that operative time differences did not significantly delay postoperative recovery. This is consistent with other studies that highlight the role of modern surgical and anesthetic techniques in minimizing perioperative complications and recovery time[14].

Complications

The hybrid THR group exhibited a lower complication rate compared to the uncemented group. Aseptic loosening was more frequent in the uncemented group (16%) compared to the hybrid group (4%), emphasizing the challenges of achieving stable biological fixation in elderly patients with poor bone quality. This finding corroborates previous studies that report higher revision rates in uncemented implants for elderly patients[15][16].

Dislocation rates were slightly higher in the uncemented group (6%) than in the hybrid group (2%), likely due to the immediate stability provided by the cemented femoral stem in hybrid THR. Periprosthetic fractures were rare in both groups but tended to occur more frequently with uncemented implants, particularly during insertion due to the need for press-fit fixation[17][18].

Comparative Analysis with Existing Literature

This study’s findings are consistent with prior research emphasizing the advantages of hybrid THR in elderly patients. For instance, Karrholm et al. demonstrated that hybrid THR reduces the risk of aseptic loosening and early revision in elderly patients with osteoporotic bone[7]. Similarly, Phillips et al. reported superior implant survival rates with hybrid THR in a long-term follow-up study[9].

Uncemented THR, on the other hand, has been widely advocated for younger, active patients due to its potential for long-term biological fixation. Studies by Berry et al. and Streit et al. have highlighted the durability and better outcomes of uncemented implants in patients under 65 years of age[6][10]. However, the need for optimal bone quality remains a limitation, as poor bone stock increases the risk of loosening and fracture[15].

Implications for Clinical Practice

The findings underscore the importance of tailoring the surgical approach to the patient’s age, bone quality, and activity level. Hybrid THR is particularly beneficial for elderly patients with osteoporosis, providing immediate stability and reducing the risk of complications. In contrast, uncemented THR remains a viable option for younger patients with good bone quality, ensuring long-term durability and reduced operative time.

Limitations and Future Directions

This study was limited by its single-center design and relatively short follow-up duration. Long-term studies are necessary to evaluate implant survival rates, especially for uncemented THR. Additionally, randomized controlled trials comparing hybrid and uncemented THR in diverse populations are warranted to strengthen the evidence base.

Both uncemented and hybrid THR are effective in managing displaced fracture neck of femur, with comparable functional outcomes over a one-year period. However, hybrid THR offers distinct advantages for elderly patients with poor bone quality, while uncemented THR is better suited for younger individuals. These findings emphasize the need for individualized surgical planning to optimize patient outcomes.

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