Comparison of dynamic hip screw surgical technique between lateral and supine positions for intertrochanteric and basicervical femur fractures

INTRODUCTION

More than 90% of hip fractures after the age of 60 years are intertrochanteric fractures, and these cases have a mortality rate of approximately 17%.^[1] In the elderly, these fractures typically result from low-energy trauma, while in younger adults, these fractures often result from high-energy trauma, such as road traffic accidents.^[2] In most cases of hip fractures, operative treatment is the best option, and several implants are available for fracture fixation.

The dynamic hip screw (DHS) is a screw used to secure the femoral head to the femoral shaft with a plate, allowing controlled dynamic sliding of the femoral head. Dynamic compression stabilizes the femur under weight-bearing stresses, thereby promoting remodeling and proper fracture healing.^[3] While this implant is recommended for the treatment of proximal femur fractures, its application requires a traction table and experience.^[4] Trochanteric fractures treated with intramedullary implants in lateral position, such as the proximal femoral nail (PFN), have shorter surgical times than those performed in the supine position on the fracture table, resulting in better fracture reduction and easier fixation.^[5] However, the literature review reveals no studies on the application of DHS in the lateral position after hip fractures. Performing DHS in the supine position poses significant technical challenges for surgeons, including a restricted field of view, limited access to the traction table, and the considerable time and expertise required for proper setup.

The purpose of this study was to describe the technique for performing DHS in the lateral position and to present short-term results compared with DHS surgery performed in the supine position.

MATERIALS AND METHODS

Patients who presented with arbeitsgemeinschaft für osteosynthesefragen-Orthopedic trauma association (AOOTA) type 31A1.1 or 31B3 femoral fractures and were fixed with DHS between November 2022 and August 2025 were included in the study. Two surgeons with prior experience operating in both supine and lateral positions performed the surgeries. The surgical position was determined by whether the last digit of the patient’s registration number was odd or even. Those with odd digits were operated in the lateral position, and those with even digits were operated in the supine position. The primary surgeon was asked to complete a form on the same day after surgery and again at the 3^rd postoperative month. The form examined patient demographics, duration of surgery, ease of reduction, surgical field of view, overall ease of surgery, number of fluoroscopy shots, quality of postoperative reduction (tip-apex distance and position of the cephalic component on the femur), implant position, and union status at 3 months postoperatively.

Surgical time, preparation time, and operation time were evaluated separately. Ease of reduction, surgical field of view, and overall ease of surgery were left to the primary surgeon’s discretion and were evaluated on a 1–10 scale. In all three evaluations, 1 point indicates the best/easiest result, while 10 points indicates the worst/most difficult result. The questionnaire is given as supplementary material. This study was retrospective in terms of data analysis. Surgeon-reported questionnaires were collected prospectively as part of routine institutional practice and subsequently reviewed retrospectively. Surgical preparation time was defined as the interval from patient entry into the operating room to skin incision. In contrast, surgery time was defined as the interval from skin incision to wound closure. Both parameters were routinely recorded by operating room nursing staff and retrieved from institutional operative records for analysis.

On postoperative day 1, AP and lateral hip radiographs were evaluated by two surgeons to assess the quality of reduction; the consensus decision of both surgeons was accepted as the final result. Reduction quality was evaluated in AP and lateral radiographs. Based on the tip-apex distance and the location of the cephalic component of the femur, reduction quality was categorized into three groups: 1-good reduction, 2-fair reduction, and 3-poor reduction. Complications that occurred during the 3-month follow-up were also noted.

DHS surgical technique in the lateral position

After anesthesia, the patient is placed in the lateral position on the contralateral hip [Figure 1].

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Figure 1:

(a-e) Lateral positioning of the patient.

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An 8–10 cm skin incision is made approximately 10 cm distal to the tip of the greater trochanter. The vastus lateralis muscle is then elevated with an L-shaped incision. The muscle is retracted with Hohmann retractors to reach the lateral aspect of the femur [Figure 2].

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Figure 2:

(a and b) The incision in the lateral position. (c and d) Opening of the vastus lateralis muscle with L-shaped incision and retraction with Hohmann retractors.

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In both groups, fracture reduction was achieved using manual traction and manipulation under fluoroscopic guidance. In the lateral position, reduction was facilitated by gravity-assisted alignment and controlled manipulation of the affected limb. When fracture stability required additional support, temporary K-wires were used to maintain reduction until definitive fixation with the DHS was completed. The number and use of temporary K-wires were determined intraoperatively according to fracture morphology and stability. Then, the K-wire intended for the DHS lag screw is advanced into the femoral neck toward the predetermined optimal position, and its placement is verified using fluoroscopic imaging in both the anteroposterior and lateral planes [Figure 3].

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Figure 3:

(a-d) Advancing the first K-wire after closed reduction of the fracture and checking with fluoroscopy, both in anteroposterior and lateral views. (e and f) Advancing the second K-wire with a guide for the dynamic hip screw.

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After drilling is performed over the K-wire, an appropriate size of lag screw is inserted into the femoral neck. Then, the distal screws of the DHS plate are inserted, and compression is applied with the fracture compression screw [Figure 4].

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Figure 4:

(a-b) Drilling over the second K-wire and implantation of the screw. (c-d) Implantation of the plate and compression of the fracture with the compression screw.

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An antirotation screw is inserted parallel to the lag screw in the appropriate position. Reduction and plate position are then checked in both planes. The vastus lateralis is repaired appropriately to prevent plate irritation. The fascia, subcutaneous tissue, and skin are then sutured respectively [Figure 5].

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Figure 5:

(a-f) Insertion of the anti-rotation screw superior to the dynamic hip screw. (g and h) Repairment of the vastus lateralis muscle and fascia.

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RESULTS

A total of 41 patients were included in the study, 21 (51.2%) in the lateral position and 20 (48.8%) in the supine position. Of the patients in the lateral position group, 10 (47.6%) had AO-OTA 31A1.1, and 11 (52.4%) had 31B3 fracture types; of the patients in the supine position group, 10 (50%) had AO-OTA 31A1.1, and 10 (50%) had 31B3 fracture types. The median age of the patients was 70 (63.5–81), 53.7% (n = 22) were female, and 46.3% (n = 19) were male. The median age was significantly lower in the supine group (P = 0.020). No significant differences were observed between BMI and the operated side. Although there was no significant difference in operative time, surgical preparation time in the operating room was shorter in the lateral position (P < 0.001); [Table 1].

The surgical field of view was significantly better in patients in the lateral position (P = 0.036). Surgeon-reported evaluations demonstrated no significant differences between the two groups regarding ease of reduction or overall ease of surgery (P > 0.05). Similarly, the number of intraoperative fluoroscopic exposures did not differ significantly between the groups (P = 0.846); [Table 2]. The reduction quality was comparable in both groups.

Nonunion was observed in one patient in the supine position and in three patients in the lateral position, and they underwent secondary surgery. Varus/valgus malalignment was observed in five patients in the supine position and in three patients in the lateral position. Early arthritis developed in one patient in the lateral position, and one patient developed a peri-implant fracture. Two patients in the supine position underwent cut-out, one patient had femoral neck shortening, and one patient had early arthritis. There was no significant difference between the two groups in terms of complications [Table 3].

DISCUSSION

The incidence of intertrochanteric fractures is increasing with the aging and growing population.^[2] DHS, a frequently used implant for stable intertrochanteric fractures, is performed with the patient in the supine position. This study is the first to describe the DHS technique performed in the lateral position in the literature and presents the initial results. DHS performed in the lateral position resulted in shorter surgical preparation time and a better surgical field of view compared to the standard supine position. It was also not inferior to the supine position with respect to complications and reduction quality. A superior field of view facilitates more accurate fracture reduction, easier identification of anatomical landmarks, and more precise implant positioning, which are critical factors in DHS fixation. Improved visualization may also reduce unnecessary soft tissue manipulation and decrease the need for repeated fluoroscopic checks, thereby potentially lowering operative time and radiation exposure. The significantly better surgical field of view observed in the lateral position supports its practical value in improving intraoperative ergonomics and surgical efficiency, especially in technically demanding cases.

While a traction table used in the supine position offers advantages in achieving and maintaining reduction, preparing the table requires time, experience, and qualified personnel. Furthermore, although this varies by country, access to a traction table is often limited, particularly in rural hospitals. A review of the literature indicates that the use of a traction table increases surgical time for intertrochanteric fractures.^[6-8] In this study, consistent with the literature, the use of a traction table was associated with increased surgical preparation time. This may be important because the patient is under anesthesia during the preparation of the traction table, and this increase in total surgical time may lead to increased complications, morbidity, and mortality rates.^[8,9] It should be acknowledged that DHS fixation in the supine position can be performed without the use of a traction table when a radiolucent carbon-fiber operating table is available. In such settings, patient positioning and surgical preparation may be simplified. However, these specialized tables are not universally accessible across all surgical centers, and traction tables continue to be widely used in routine clinical practice. Consequently, preparation time and technical complexity associated with the supine position may vary depending on the available equipment and institutional resources.

One of the most significant challenges during surgery for intertrochanteric fractures is achieving reduction and maintaining it throughout the operation.^[10] This is where the advantage of using a traction table becomes evident. In this study, when primary surgeons were rated on factors such as achieving and maintaining reduction during surgery, and having a comfortable operation throughout the surgery, no difference was observed between the two groups. This may be due to the fact that the patients who underwent DHS in the study had stable fractures (AO-OTA 31A1.1 and 31B3). For stable fractures, achieving reduction and performing surgery in either position were comparable. The rationale for considering stable fractures in the study is that, in the current literature, PFN is more commonly recommended than DHS for unstable fractures.^[11,12]

Another parameter examined in this study was the surgical field of view. Postoperative scoring revealed that surgeons had a better view of the surgical field in the lateral position. While there was no difference in BMI among the patients in our study, thick soft tissue layers, especially in obese patients, reduce the surgical field of view. However, because of the lateral position, loose tissues are distributed to both the anterior and posterior sides, thereby improving the surgical field of view. It is understandable that a better surgical field of view makes surgeons feel more confident and undoubtedly makes surgery easier. However, larger studies are needed to draw definitive conclusions on this matter.

Daniels et al. reported that more fluoroscopy images were obtained during proximal femoral nailing performed in the lateral position to maintain reduction and to align the fluoroscopy device.^[9] However, other studies have shown no difference in the number of fluoroscopy images in surgeries performed in both positions.^[7,8,13,14] In this study, no difference was observed in the number of fluoroscopy shots in either position. This may be due to experience with the surgical technique. In our clinic, the lateral position is frequently used in post-hip fracture treatment (PFN, DHS, arthroplasty), and this experience reduces and optimizes the number of fluoroscopy exposures in the lateral position.

While the reduction and fixation of proximal femoral fractures pose challenges, new strategies are continually being developed to achieve better fixation and to prevent complications, such as inadequate fixation requiring secondary surgery. There is no definitive evidence that surgical positioning reduces the failure rate in intertrochanteric fractures.^[15] In the literature, no differences were found in tip-apex distance, collodiaphyseal angle, lag screw position, or reduction quality across the Cleveland-Bosworth classification in surgeries performed in both positions.^[16-20] In this study, the reduction quality (tip-apex distance and cephalic component position in the femur) was comparable between the two groups.

Complications were also taken into account when interpreting the results. No significant differences were observed between the groups regarding fixation failure or need for revision surgery. These findings suggest that both positioning techniques are comparable in terms of safety, although the improved surgical field of view in the lateral position may offer practical intraoperative advantages.

The study has several limitations. It was retrospective in design. The number of patients was limited, but the primary objective was to demonstrate the use of DHS in the lateral position. However, functional outcomes and clinical complications (e.g., hospital readmissions and mortality) were not examined. It should be acknowledged that the assessment of the surgical field of view is inherently subjective. To minimize variability, a standardized postoperative questionnaire with a predefined scoring system was used for all surgeons. Nevertheless, the subjective nature of surgeon-reported evaluations represents a limitation of the study and should be considered when interpreting the results.

CONCLUSION

DHS in the lateral position is a feasible method for intertrochanteric fractures. DHS performed in the lateral position resulted in shorter operating room preparation time and a better surgical field of view compared to the standard supine position. It was not inferior to the supine position with respect to complications or reduction quality. It can be used, especially in areas with a shortage of skilled personnel and equipment. However, multicenter prospective studies with larger patient cohorts are needed to yield more reliable results.