Total hip arthroplasty (THA) is one of the orthopedic procedures that is commonly used for relieving pain, restoring mobility, and improving quality of life.¹ It is used in  end-stage hip diseases such as osteoarthritis, avascular necrosis, rheumatoid arthritis, and femoral neck fractures.Due to the rising trend  of degenerative joint disorders, the number of THA procedures performed worldwide continues to increase. Postoperative complications such as dislocation, muscle damage around the hip, blood loss, and delayed functional recovery are important factors affecting the satisfaction of the patient.² Therefore, many surgical approaches have been identified to THA  that affects perioperative complications and functional outcomes³. These are direct anterior approach (DAA), posterior approach (PA), and posterolateral approach (PLA).Posterior approach or posterolateral approach  allow the surgical site to be fully exposed, but there are some drawbacks like the risk of posterior dislocation of the hip after surgery is higher as it requires cutting off the short external rotator of the hip.Now a days DAA is performed on the anterior hip joint through the interval between the tensor fascia lata and sartorius muscle and nerve space without damaging any muscles.⁴  Radiological and magnetic resonance imaging studies have also shown  better protection of periarticular muscles and soft tissues following DAA. Compared with the outcomes of other approaches, the DAA has the advantages of more rapid postoperative recovery, and less pain.⁵This retrospective study compared clinical and functional outcomes in THA between patients in the DAA and PLA groups. Additionally, DAA is associated with a steeper learning curve and may require longer operative time during the initial stages of adoption. Given these conflicting findings, further evaluation of clinical and functional outcomes associated with these approaches is required⁶.Therefore, the present retrospective study was undertaken to compare the direct anterior and posterolateral approaches in patients undergoing total hip arthroplasty.⁷ The study aimed to evaluate operative parameters,  postoperative functional recovery, Harris Hip Scores,  to determine whether the muscle-sparing characteristics of DAA translate into superior clinical outcomes compared with the conventional posterolateral approach.

AIM

To compare the clinical, functional, and radiological outcomes of THA performed using the Direct Anterior Approach versus the Posterolateral Approach.

This retrospective comparative study was conducted at the.. Department of Orthopaedics from january 2025 to december 2025. A total of 96 patients were included in the study .They are divided into two groups based on the surgical approach used: Direct Anterior Approach (DAA) group (n = 48) and Posterolateral Approach (PLA) group (n = 48). The included studies (i) patients undergoing primary THA; patients underwent the DAA for THA; patients underwent the PLA for THA; the incision length, intraoperative blood loss, operative time, length of stay, Harris hip score, CK level, and complications were documented. Patients with previous hip surgery, neuromuscular disorders , pathological fractures, active infection, or incomplete medical records were excluded from the study. Demographic data including age, sex, body mass index (BMI), affected side, diagnosis, and comorbidities were collected. Intraoperative parameters such as operative time, estimated blood loss, incision length, transfusion requirement, and duration of hospital stay were recorded. Postoperative clinical outcomes were also assessed.

Table 1. General Characteristics of the Two Groups

 The mean age was 61.8 ± 8.4 years in the DAA group and 63.1 ± 7.9 years in the PLA group, with comparable distributions of gender, BMI, operated side, and underlying diagnoses including osteoarthritis, avascular necrosis of the femoral head, and neck of femur fracture between the two groups.

Table 2. Comparison of Clinical Indexes During Operation

DAA group had a significantly longer mean operative time (93.4 ± 11.6 minutes) than the PLA group (79.2 ± 10.4 minutes). However, patients in the DAA group experienced lower intraoperative blood loss (312 ± 64 ml vs. 381 ± 72 ml), smaller incision length (8.4 ± 1.1 cm vs. 11.2 ± 1.4 cm) (p<0.05), fewer blood transfusions (3 vs. 7), and a significant shorter hospital stay (4.8 ± 1.0 days vs. 6.1 ± 1.2 days) compared to the PLA group.

Table 3.Comparison of Radiographic Analysis Between the Two Groups

 femoral component positions of 0.7 ± 1.4° in the DAA group and 0.9 ± 1.6° in the PLA group. Femoral component varus alignment greater than 2° was observed in 14.6% and 18.8% of patients, respectively, while the mean acetabular abduction angle was 47.8 ± 3.8° in the DAA group and 46.9 ± 4.5° in the PLA group.Acetabular abduction angles below 55° were achieved in 95.8% of patients in the DAA group and 93.8% in the PLA group. Similarly, acetabular anteversion within the safe zone was observed in 91.7% and 87.5% of patients, respectively, while the mean leg length discrepancy was slightly lower in the DAA group (3.2 ± 2.1 mm) compared to the PLA group (4.1 ± 2.8 mm).

Table 4. Comparison of Harris Hip Scores

The mean preoperative Harris Hip Score (HHS) was comparable between the DAA and PLA groups (44.2 ± 6.1 vs. 43.8 ± 6.5). Postoperatively, both groups showed progressive improvement in HHS; however, the DAA group demonstrated significantly better functional scores at 1 month, 3 months, and 6 months, while the scores at 12 months were comparable between the two groups (93.4 ± 2.6 vs. 92.7 ± 2.8).

Table 5. Comparison of Harris Hip Pain (VAS)

The mean preoperative VAS pain scores were comparable between the DAA and PLA groups (7.8 ± 0.8 vs. 7.7 ± 0.9). Postoperatively, pain scores decreased significantly in both groups; however, the DAA group consistently demonstrated lower VAS scores on day 1, day 7, 1 month, and 6 months.

Table 6. Comparison of Complications

 Dislocation occurred less frequently in the DAA group (2.1%) compared to the PLA group (6.3%), while superficial infection rates were similar in both groups (4.2%).Deep infection and revision surgery were observed only in the PLA group, whereas nerve injury occurred only in the DAA group. The rates of periprosthetic fracture and deep vein thrombosis were low and comparable between the two groups.

The mean age of patients was 61.8 ± 8.4 years in the DAA group and 63.1 ± 7.9 years in the PLA group. 30 males and 18 females in the DAA group and 29 males and 19 females in the PLA group. The mean BMI was comparable between the groups. 27 patients in the DAA group and 25 patients in the PLA group underwent right hip arthroplasty. Osteoarthritis , followed by avascular necrosis of the femoral head and fracture neck of femur, with a similar distribution of diagnoses in both groups. Wang Z et al8 reported similar no significant difference in baseline characteristics between patients in the two groups (p > 0.05). The mean operative time was higher in the DAA group (93.4 ± 11.6 minutes) compared to the PLA group (79.2 ± 10.4 minutes). However, the DAA group showed lower mean blood loss, shorter mean incision length, fewer blood transfusions required in the DAA group than in the PLA group. Furthermore, patients undergoing DAA had a shorter mean hospital stay (4.8 ± 1.0 days) compared to those undergoing PLA (6.1 ± 1.2 days), indicating faster postoperative recovery.Ang, J.J.M., et al9 in their study showed Twenty-four studies comprising 2010 patients were included in this meta-analysis. DAA has a longer operative time (MD = 17.38 min, 95%CI: 12.28, 22.47 min, P < 0.001) but a shorter length of stay compared to PA (MD = − 0.33 days, 95%CI: − 0.55, − 0.11 days, P = 0.003). There was no difference in operative time or length of stay when comparing DAA versus LA. The mean femoral component position was 0.7 ± 1.4° in the DAA group and 0.9 ± 1.6° in the PLA group, Femoral component varus alignment greater than 2° was observed in 7 and 9 patients (18.8%) respectively. The mean acetabular abduction angle was 47.8 ± 3.8° in the DAA group compared with 46.9 ± 4.5° in the PLA group, with acetabular abduction angles below 55° achieved in 95.8% and 93.8% of patients, respectively. Acetabular anteversion within the safe zone was observed in 44 patients (91.7%) in the DAA group and 42 patients (87.5%) in the PLA group. While, the mean leg length discrepancy was lower in the DAA group (3.2 ± 2.1 mm) than in the PLA group (4.1 ± 2.8 mm), suggesting satisfactory and comparable radiographic outcomes with both surgical approaches.Jin, Z., Wang et al10 No significant difference was observed in HHS at 1 week, 3 months, and 6 months postoperatively, VAS postoperatively at each time point, acetabular anteversion angle, acetabular abduction angle, wound infection, deep vein thrombosis, and intraoperative fracture (p > 0.05). The mean preoperative HHS was comparable between the DAA and PLA groups, measuring 44.2 ± 6.1 and 43.8 ± 6.5, respectively. The DAA group showed higher HHS values at 1 month (80.4 ± 4.8 vs. 75.9 ± 5.2), 3 months (87.3 ± 4.1 vs. 82.5 ± 4.5), and 6 months (91.6 ± 3.2 vs. 89.4 ± 3.8) compared to the PLA group. At 12 months, the HHS remained slightly higher in the DAA group (93.4 ± 2.6) than in the PLA group (92.7 ± 2.8). This is inconsistent with Moerenhout K et al.11 There was a trend toward a better functional outcome for patients who underwent the direct anterior approach in the first 3 months postoperatively, with a peak at 4 weeks (Harris Hip Score 76.7 v. 68.7; p = 0.08). The mean preoperative VAS scores were similar in the DAA and PLA groups, measuring 7.8 ± 0.8 and 7.7 ± 0.9, respectively. Patients in the DAA group reported lower pain scores on postoperative day 1 (3.4 ± 0.7 vs. 4.1 ± 0.8) and day 7 (2.0 ± 0.5 vs. 2.5 ± 0.6) compared to the PLA group. The DAA group also maintained lower VAS scores at 1 month (1.2 ± 0.4 vs. 1.6 ± 0.5) and 6 months (0.6 ± 0.2 vs. 0.7 ± 0.3). These findings are inconsistent with Lin et al12 study where Significant differences (P < .001) were observed in the visual analog scale scores of the patients in the study group at 1 day (6.71 ± 0.46), 3 days (5.71 ± 0.46), and 1 week (0.96 ± 0.20) after surgery, in comparison with the control group (7.46 ± 0.51, 6.35 ± 0.49, 1.73 ± 0.67). Dislocation was observed in 1 patient (2.1%) in the DAA group and 3 patients (6.3%) in the PLA group. Superficial infection occurred in 2 patients (4.2%) in each group, while deep infection was reported in 1 patient (2.1%) only in the PLA group. Nerve injury was noted in 2 patients (4.2%) in the DAA group, whereas no such cases were observed in the PLA group. Periprosthetic fracture and deep vein thrombosis occurred infrequently and showed similar rates between the groups, while revision surgery was required in 1 patient (2.1%) in the PLA group and none in the DAA group. Similar to our study Ang, J.J.M., et al9 reported no significant difference in risk of neurapraxia for DAA versus LA or in risk of dislocations, periprosthetic fractures or VTE between DAA and PA or DAA and LA.

The present study showed that both the  approaches  are safe and effective surgical techniques for total hip arthroplasty, which provide  improvement in hip function and pain relief. Patients having DAA showed advantages in terms of lower intraoperative blood loss, smaller incision length, reduced need for blood transfusion, shorter hospital stay, better early functional recovery, and lower postoperative pain scores compared to those undergoing PLA.

Radiographic evaluations are comparable  in both groups.The incidence of complications was low in both groups, the DAA group had a lower rate of dislocation. Long-term functional outcomes and overall complication rates were comparable between the two approaches.

Therefore, while both approaches provide excellent clinical and radiological outcomes following total hip arthroplasty, the Direct Anterior Approach offers the advantage of faster early recovery, reduced postoperative pain, and earlier restoration of function, making it more beneficial to the traditional Posterolateral Approach in  selected patients.