Abstract
Objective
There are various treatment methods for pubic symphysis diastasis, this study explores the advantages and limitations of using a modified internal fixator to treat pubic symphysis diastasis.
Methods
A total of 31 patients with pubic symphysis diastasis were treated with modified internal fixator at our institution from January 2020 to January 2024, and the clinical data of these patients were retrospectively analyzed. Patient data collected included age, gender, cause of injury, fracture typing, incision length, operative time, intraoperative bleeding, time from injury to surgery, quality of reduction, complications, and postoperative function. The quality of reduction was assessed using the Matta radiologic criteria, and the degree of functional recovery after pelvic fracture was evaluated using the Majeed scale at follow-up.
Results
According to AO/OTA staging, 20 patients with type B2 were treated with modified internal fixator combined with 1 sacroiliac screw, 6 patients with type C1 were treated with modified internal fixator combined with 2 sacroiliac screws, and 5 patients with type C1 were treated with modified internal fixator combined with posterior spinal pelvic triangular fixation. The patients' surgical incision length was 4.0–5.3 cm, mean 4.75 cm, intraoperative bleeding was 68–101 ml, mean 85.58 ml, operative time was 55–77 min, mean 64.39 min, width of the pubic symphysis was 4.4–6.6 mm, mean 5.45 mm and the injury-to-operative time was 3–13 days, mean 7.03 days. The Majeed score was 90.23 points (range 81–96 points), with 25 cases with excellent and 6 cases with good, with an excellence rate of 100%. According to the Matta scale, there were 21 excellent cases and 10 good cases, with an excellent rate of 100%.
Conclusion
In conclusion, the findings of this retrospective study preliminarily indicate that the M-INFIX is a promising, minimally invasive treatment option for pubic symphysis diastasis. The technique demonstrated satisfactory radiographic reduction, excellent functional recovery, and a low complication rate in our patient cohort. However, it is important to emphasize that the retrospective design and relatively small sample size limit the generalizability of these findings. Therefore, the exact efficacy and comparative advantages of M-INFIX warrant further validation through larger-scale, prospective, randomized controlled studies.
Keywords: Internal fixator, Pelvic fracture, Pubic symphysis diastasis
Introduction
Pubic symphysis diastasis (PSD) is an injury typically resulting from high-energy trauma that disrupts the ligaments and fibrocartilaginous disc of the pubic symphysis, leading to anterior pelvic ring instability [1]. Pelvic ring injuries involving PSD account for approximately 24% of all pelvic fractures [2]. Restoring stability to the pubic symphysis is critical for achieving anatomical alignment of the pelvic ring, reducing pain, and enabling functional recovery[3].In recent years, plates, hollow screws, and external fixation are mostly used to treat PSD [3, 4]. However, each modality has inherent limitations. Internal fixation of plate has the risks of high surgical trauma, high bleeding, easy to damage vascular nerve bundles during surgery, and infection of surgical incision [5]. Percutaneous screw fixation minimizes soft tissue disruption but demands substantial fluoroscopic guidance, increasing radiation exposure, and may offer less biomechanical stability [6]. External fixation often interferes with the patient's daily life and can also bring complications such as nail channel infection and screw loosening [7, 8].Therefore, the optimal fixation method of PSD has been controversial [9].
In 2009, Kuttner first reported the use of an internal fixator (INFIX) for the treatment of anterior pelvic ring injuries, INFIX has been widely applied in clinical practice due to its minimal trauma and has achieved satisfactory clinical results [10].But it is not suitable for anterior pelvic ring injuries combined with PSD, because PSD is often accompanied by vertical displacement, and the INFIX technique cannot stabilize the vertical displacement of the pubic symphysis. INFIX is also associated with complications such as lateral femoral cutaneous nerve(LFCN) irritation, femoral nerve palsy, implant loosening and heterotopic ossification [11, 12].To address these issues, our team modified the INFIX in the clinic by adding two polyaxial pedicle screws at the bilateral pubic tubercle and removing the pedicle screws at the contralateral AIIS (Fig. 1). Modified internal fixation(M-INFIX) uses the two middle pedicle screws as support points, and is supplemented by one screw fixed at the anterior inferior iliac spine, which can provide reliable stability. Currently, there are no reports of M-INFIX for the treatment of PSD, we used M-INFIX for the first time in our clinic to treat PSD. Therefore, this study aimed to retrospectively evaluate the clinical and radiological outcomes of this novel M-INFIX technique in managing PSD, assessing its feasibility, safety, and early efficacy.
Fig. 1.
The incision designed for M-INFIX. The two incisions are located on the anterior inferior iliac spine and over the pubic symphysis on one side, and the multiaxial screws are placed medially in the anterior inferior iliac spine and bilaterally in the pubic symphysis. A subcutaneous tunnel is created from the anterior inferior iliac spine incision toward the pubic symphysis, which allows manual insertion of titanium rods. a Lateral femoral cutaneous nerve; b Iliopsoas muscle; c Femoral nerve; d Suture muscle; e Quadriceps muscle; f External iliac artery; g External iliac vein
Patients and methods
We conducted a single-center, retrospective review of patients with pelvic fractures who were admitted to our department between January 2020 and January 2024. The inclusion criteria were as follows: 1. pelvic fracture with PSD; 2.PSD treated with M-INFIX;3. follow-up time greater than 6 months. 4.age greater than 16 years. Exclusion criteria included the following: 1. bilateral anterior pelvic ring injuries (the design of the M-INFIX is only applicable to unilateral injuries of the anterior pelvic ring.); 2. more than 21 days between injury and surgery (difficult to reduce after more than 21 days); 3. severe osteoporosis.
All patients provided informed consent and signed the informed consent form for this study. This study was approved by the Ethics Committee of the First Affiliated Hospital of Bengbu Medical College. Between January 2020 and January 2024, a total of 31 patients were included based on inclusion and exclusion criteria. By retrospectively analyzing the clinical data of these patients, the patient data collected included age, gender, cause of injury, fracture typing, incision length, operative time, intraoperative bleeding, time from injury to surgery, quality of reduction, complications, and postoperative function. These indicators allow us to compare our data with previously reported results. Preoperative CT scan reconstruction of the pelvis and multi-angle radiographs of the pelvis (anteroposterior, inlet, outlet, iliac obliquity, and occlusion obliquity of the pelvis) were taken, and pelvic fractures were staged according to the AO/OTA classification method.
Surgical treatment
In patients with AO/OTA staging type B2, fixing the posterior ring of the pelvis first may potentially affect the reduction of the anterior ring of the pelvis. The anterior pelvic ring was reset and immobilized with M-INFIX, followed by sacroiliac joint screw fixation of the posterior ring. After general anesthesia the patient was placed supine in a fluoroscopic surgical bed. A 3 cm oblique incision centered on the AIIS was made to separate the muscle space between the vastus tensor fasciae latae and the suture muscles in order to completely expose the AIIS. The opening was made 1 cm lateral to the AIIS with a pedicle opener, confirming that the channel was located between the internal and external iliac plates, and screwing in one polyaxial pedicle screw in diameter. Then, a 4 cm long transverse incision was made above the pubic symphysis, the skin, subcutis, fascia and abdominal white line were cut, the rectus abdominis muscle was retracted to both sides, and the peritoneum and bladder were pushed to the posterior side. Two polyaxial pedicle screws with a diameter of 6.5 mm and a length ranging from 45 to 50 mm were implanted bilaterally near the pubic tubercles at an appropriate depth. The pubic symphysis is reset by using a pressurizer to compress the pedicle screw at the pubic symphysis. If there is a vertical displacement of the pubic symphysis that is difficult to reset, the vertical displacement is reset by a resetting clamp that holds the suprapubic branch displaced upward on one side and the infrapubic branch displaced downward on the contralateral side. Finally, the connecting rods are shaped into different curvatures and lengths according to the patient's body shape, and the shaped connecting rods are inserted subcutaneously into the pedicle screws. If there is a fracture of the pubic branch, the lead surgeon and assistant fix the pubic symphysis and AIIS, obtain fracture reduction by means of compression or traction. X-ray fluoroscopy showed that the pubic symphysis and the fracture end were satisfactorily reduction (the width of the pubic symphysis is less than 1 cm), and the three pedicle screws were sequentially locked to complete the fixation. When the C-arm X-ray machine fluoroscopy showed satisfactory reduction of the posterior pelvic ring, sacroiliac joint screws were implanted throughout the fluoroscopy to fix the posterior pelvic ring (Fig. 2).
Fig. 2.
A 52-year-old male with crush injury, AO/OTA B2 type. a-c Preoperative pelvic anteroposterior (a), inlet (b) and outlet (c) X-ray films showing the pubic symphysis diastasis and loss of pelvic ring stability. d-f Postoperative pelvic anteroposterior (d), inlet (e) and outlet (f) X-ray films showing the satisfactory reduction with M-INFIX and sacroiliac screws. g-i Postoperative pelvic anteroposterior (g), inlet (h) and outlet (i) X-ray films after removal of the M-INFIX, showing the healed pubic symphysis at postoperative 12 months during the follow-up
For patients with AO/OTA staging type C1, preoperative bone traction was performed on the femoral condyle or tibial tuberosity with a traction weight of 1/7 of the body weight. During the surgery, the posterior ring sacroiliac-pelvic triangle fixation was performed first, as we had to correct the vertical displacement of the posterior pelvic ring initially. After completing the reduction and fixation of the posterior ring, the anterior ring M-INFIX fixation was performed. The patient was positioned in the prone position and a posterior median incision was made, the skin, subcutaneous tissue and fascia were incised layer by layer, and the paravertebral muscles were incised longitudinally, and pedicle screws were placed in the L4 and L5 pedicles according to Weinstein's localization method. Then the sacral posterior foramen was revealed, and a hole was made in the midline between the lower edge of the posterior foramen of S1 and the upper edge of the posterior foramen of S2 in the direction of the AIIS. After probing that the bone channel was located between the inner and outer plates of the ilium, a polyaxial pedicle screw was screwed in, and a connecting rod of appropriate length was taken to connect the three screws. Depending on the fracture or dislocation, reduction is accomplished by applying pressure or bracing and tightening the nut. Finally, sacroiliac screws and M-INFIX were placed, which were placed in the same manner as in type B2 patients (Fig. 3).
Fig. 3.
A 60-year-old male with a fall injury from a height, AO/OTA C1 type. a-d Preoperative pelvic 3-D CT (a), anteroposterior (b), inlet (c) and outlet (d) X-ray films showing the pubic symphysis diastasis and posterior ring instability. e–g Postoperative pelvic anteroposterior (e), inlet (f) and outlet (g) X-ray films showing the satisfactory reduction with M-INFIX and spinal pelvic triangle fixation. h-j Postoperative pelvic anteroposterior (h), inlet (i) and outlet (j) X-ray films after removal of the M-INFIX, showing the healed pubic symphysis and posterior ring at 12 months during the follow-up
Postoperative management
Patients were given prophylactic antibiotics for 1 day and oral anticoagulants for 2 weeks (type B2 patients) or 1 month(type C1 patients) after surgery, and were encouraged to perform quadriceps exercises in the hospital bed starting on the 3rd postoperative day. Patients should be followed up and X-rays should be taken at the 1 st, 2nd, 3rd, 6th, 9th,12th, 15th, 18th, 21th, 24th, 27th, 30th, 33th and 36th months after the operation. Patients with type B2 began to walk with crutches in the second week after surgery, and patients with type C1 began to walk with crutches in the third week after surgery and gradually increased weight bearing. Based on postoperative review, full weight bearing is recommended 6 weeks postoperatively for type B2 patients and 8 weeks postoperatively for type C1 patients. The sacroiliac joint screws were not removed in all patients. For the removal of M-INFIX, we consider it at least three months later. Furthermore, during the follow-up period, there was no loss of reduction and no clinical symptoms were observed.
Clinical and radiological analysis
The quality of the reduction was assessed on the basis of the maximum displacement of the fracture on anteroposterior, inlet, and outlet radiographs of the pelvis within one week after surgery by a senior trauma orthopedic surgeon. The quality of pelvic fracture reduction was evaluated using the Matta scale [13], in which fracture displacement < 4 mm was considered excellent, displacement 4–10 mm was considered good, displacement 11–20 mm was considered fair, and displacement > 20 mm was considered poor. The Majeed score was used to evaluate the degree of functional recovery after pelvic fracture at final follow-up [14]. The score was evaluated in terms of pain (30 points), work (20 points), sitting (10 points), sexual intercourse (4 points), and standing (36 points), with a full score of 100 points; 85–100 points was excellent, 70–84 points was good, 55–69 points was fair, and < 55 points was poor.
Results
All patients were followed up, the 31 patients included 14 females and 17 males with an age range of 25 to 67 years and a mean age of 44.77 ± 10.33 years. According to the cause of their injuries, there were 13 cases of traffic accident injuries, 11 cases of fall from height injuries, and 7 cases of crush injuries. Most patients with type C pelvic fractures are caused by falls, while most patients with type B pelvic injuries are caused by motor vehicle accidents and crush injuries. For patients with pelvic injury type C1, if the closed reduction is satisfactory, the posterior ring should be fixed with sacroiliac screws; if the reduction is unsatisfactory, a posterior spinal-pelvic triangle fixation should be adopted. According to AO/OTA staging, 20 patients with type B2 were treated with modified internal fixator combined with 1 sacroiliac screw, 6 patients with type C1 were treated with modified internal fixator combined with 2 sacroiliac screws, and 5 patients with type C1 were treated with modified internal fixator combined with posterior spinal-pelvic triangular fixation (Table 1).
Table 1.
Patient demographics
| M-INFIX | Range/percentage | |
|---|---|---|
| Age (years) | 44.77 ± 10.33 | 25–67 |
| Gender (male: female) | 17:14 | 54.84%:45.16% |
| Fracture type (B2:C1) | 20:11 | 64.52%:35.48% |
| Mechanism of injury | ||
| Traffic accidents (n) | 13 | 41.94% |
| Crush (n) | 7 | 22.58% |
| Fall from height (n) | 11 | 35.48% |
| Time from injury to operation (days) | 7.03 ± 2.67 | 3–13 |
| Operation time (min) | 64.39 ± 5.82 | 55–77 |
| Intraoperative blood loss (ml) | 85.58 ± 8.73 | 68–101 |
| Follow-up (months) | 18.35 ± 3.64 | 12–24 |
| Incision length(cm) | 4.75 ± 0.46 | 4.0–5.3 |
| Majeed evaluation score | 90.23 ± 3.78 | 81–96 |
| Pubic symphysis width(mm) | 5.45 ± 0.57 | 4.4–6.6 |
All patients were followed up for 12 to 24 months with a mean of 18.35 ± 3.64 months. The patients' injury-to-operative time was 3–13 days, mean 7.03 ± 2.67 days. The patients' operative time was 55–77 min, mean 64.39 ± 5.82 min. The patients' intraoperative bleeding was 68–101 ml, mean 85.58 ± 8.73 ml. The patients' surgical incision length was 4.0–5.3 cm, mean 4.75 ± 0.46 cm. The patients' width of the pubic symphysis was 4.4–6.6 mm, mean 5.45 ± 0.57 mm (Table 1).The Matta scoring standard was used to evaluate the quality of reduction, and there were 21 cases (67.74%) with excellent and 10 cases (32.26%) with good; the Majeed scoring standard was used to evaluate the postoperative function of the patients, and the score was 90.23 ± 3.78 points (range 81–96 points), with 25 cases (80.65%) with excellent and 6 cases (19.35%) with good (Table 2).
Table 2.
Assessments of clinical outcomes
| M-INFIX | Percentage (%) | |
|---|---|---|
| Majeed evaluation | ||
| Excellent (n) | 25 | 80.65% |
| Good (n) | 6 | 19.35% |
| Fair (n) | 0 | 0% |
| Poor (n) | 0 | 0% |
| Matta reduction criteria | ||
| Excellent (n) | 21 | 67.74% |
| Good (n) | 10 | 32.26% |
| Fair (n) | 0 | 0% |
| Poor (n) | 0 | 0% |
| Complications | ||
| Loosening of screws (n) | 0 | 0% |
| Femoral nerve palsy (n) | 0 | 0% |
| LFCN irritation (n) | 0 | 0% |
| Incision infection (n) | 1 | 3.22% |
In the 31 patients in this study, all postoperative radiographs showed satisfactory reduction of the pubic symphysis and good position of the internal fixation without entering the pelvis or acetabulum. At the final follow-up, all pelvic X-rays showed no loss of pubic symphysis reduction. In this study, there were no complications of femoral nerve palsy and LFCN irritation, and no breakage, loosening, or detachment of the internal fixation. One patient developed a superficial infection of the skin of the incision above the pubic symphysis, which disappeared after simple debridement treatment and oral antibiotics. This case of incisional infection occurred during the early clinical application of M-INFIX, where the surgeon's insufficient experience led to a prolonged surgical duration and extended exposure of the incision, thereby increasing the risk of infection (Table 2).
Discussion
The pubic symphysis is a micromotor joint formed by the pubic bodies on both sides in the anterior pelvic ring, and a fibrocartilaginous disk in the middle, which plays a key role in maintaining pelvic stability [15, 16]. Injuries in PSD are mostly caused by high-energy trauma mechanisms and are a common injury type in anterior pelvic ring injuries, which are reported in the literature to account for approximately 13–16% of pelvic fractures [17]. For patients with PSD, relying solely on imaging to determine a symphysis pubis distance greater than 2.5 cm as a surgical criterion is not sufficiently accurate. Surgical treatment may be considered when there is posterior ring instability, failure of manual reduction, the patient's inability to tolerate or refusal of conservative treatment, or when it is determined that conservative treatment will result in symptoms affecting the patient's quality of life [18].
In recent years, with the deeper study of PSD and the development of minimally invasive techniques, researchers have come up with many ideas and treatment modalities. External fixation for the treatment of PSD has poorer mechanical stability than internal fixation and there are complications such as nail channel infection,screw loosening and interference with the patient's daily life [19, 20]. Due to the inherent physiological mobility of the pubic symphysis, the use of plates for the treatment of PSD exhibits a high failure rate and a low revision rate [21, 22], and the loss of pubic symphysis reduction seriously affects patients' postoperative functional recovery [23]. The process of stripping is prone to damage the nerves, blood vessels, bladder, and occlusive arteries at the groin [24]. The use of hollow screws for fixation of the pubic symphysis is somewhat blinding because it is not operated under direct vision, and there is a risk of injury to the occlusal vascular nerve bundles, the spermatic cord in males (round ligament of the uterus in females). Therefore, this requires surgeons to possess extensive surgical experience, while inevitably exposing both surgeons and patients to multiple radiation doses [24, 25].
The average surgical incision length above the pubic symphysis in this study was 4.75 cm, which was shorter than the incision length reported in previous literature for plate fixation [3]. We believe that the reason for this may be that pedicle screws are easier to place and fixate and require less surgical exposure than plate screw systems. When PSD combined with pubic branch fracture, most scholars chose incisional reduction and fixation with a long plate. In this study, the average operative time was 64.39 min, and the intraoperative blood loss was 85.58 ml, both of which were lower than those reported in previous literature for the plate fixation method [3, 26]. We believe the reasons for this are that incisional reduction and the use of long plates for internal fixation implies long surgical incision and high degree of trauma, which can lead to increased bleeding; poorly fitting plates, complex surgical maneuvers, and intraoperative neurovascular injuries result in long surgery times. We summarize that there are 2 advantages of using M-INFIX for fixation of PSD combined with pubic branch fracture as follows: 1. The length of the surgical incision is greatly reduced in comparison with the long plate fixation, which reduces the scope of exposure required for the surgery, greatly reduces the surgical trauma, and reduces the amount of intraoperative bleeding; 2. M-INFIX can fix two injuries at the same time by one fixation method, avoiding the problems of complicated operation, long operation time and many complications. No breakage, loosening, or dislodgement of the internal fixation occurred in this study. Compared to other fixation methods, M-INFIX may offer the advantage of reducing the risk of fixation failure when some literature reports have indicated that external fixation loosening and internal fixation failure[7–9, 27]. M-INFIX does not require multiple fluoroscopies intraoperatively and avoids the problem of multiple exposures of the operator and patient to radiation during hollow screw fixation. No vascular or neural injuries were observed in this study. Compared with other internal fixation methods, M-INFIX may offer the advantage of reducing the risk of neural and vascular injuries.
In 2012, Vaidya et al. [28] described the INFIX technique in detail, which was used clinically for the treatment of anterior pelvic ring injuries with satisfactory efficacy, but INFIX is not suitable for anterior pelvic ring injuries combined with PSD, which is attributed to the fact that the INFIX technique does not stabilize the vertical displacement of the pubic symphysis. In recent years, scholars have attempted to treat PSD by modifying INFIX or combining INFIX with hollow screws. Wang et al. [26, 29] implanted one pedicle screw on each side of the pubic tubercle and attached the screws to the INFIX for the treatment of patients with PSD; Chen et al. [30] treated patients with PSD using the INFIX combined with a hollow screws. In 2019, Christopher et al.'s [31] biomechanical research found that M-INFIX had better biomechanical stability in a variety of surgical approaches to fixate the anterior ring. There were no complications of screw loosening, breakage, or dislodgement in this study, whereas 2 screw loosening complications occurred in 46 patients in Wang's study. The reason for this may be that the strength of the M-INFIX pedicle screws and connecting rods can counteract the more powerful stress effects, and the vertical instability of the pubic symphysis is also immobilized, which drastically reduces the probability of internal fixation failure. INFIX has been reported in the literature to have an LFCN rate of up to 27% due to the need to place pedicle screws in the AIIS bilaterally [12]. Osterhoff et al. [32] found that blood vessels and nerves can be kept safe when the distance between the connecting rod and the bone surface is maintained at more than 2 cm and noted that the caudal end of a long connecting rod can stimulate the LFCN to cause symptoms. Three cases of femoral nerve palsy symptoms and six cases of LFCN irritation were seen in 46 patients in Wang's study, and one case of femoral nerve compression symptoms and one case of LFCN irritation were seen in 12 patients in Chen et al.'s study. Differences in patient populations or surgical techniques may influence the occurrence of such complications. There were no complications of nerve injury in this study due to possible reasons: 1. M-INFIX does not cause damage to the contralateral LFCN and femoral nerve, and therefore M-INFIX avoids the problem of high nerve damage rate. 2. The M-INFIX connecting rod has a smaller curvature and shorter length, which makes it simpler and easier to maneuver when it is inserted subcutaneously, which reduces the incidence of femoral nerve injury, and the shorter end of the connecting rod reduces the irritation to the LFCN.
The mean Majeed score in this study was 90.23 (range 81–96), with an excellence rate of 100%. According to previous literature reports, our method achieves a higher excellent rate compared to other fixed methods, yet we have not conducted a comparative study thus far [3, 26, 29, 30]. During the follow-up, we found that patients who applied M-INFIX felt more comfortable in their lives, probably because the length of the connecting rod is only half of that of INFIX, which does not affect the patients' daily dressing, getting up and sitting, standing and walking. In this study, according to the Matta criteria, the excellent and good rate of reduction quality reached 100%, which is higher than the excellent and good rates reported in previous literature for other fixation methods [3, 26, 29, 30]. It may be related to the following reasons:1. M-INFIX not only strengthens the horizontal stability of the pubic symphysis, but also plays a role in stabilizing the vertical instability of the pubic symphysis.2. M-INFIX firstly disposes of the pedicle screw into the pubic symphysis, which can help to reset the bone through the pedicle screw. In addition, the pedicle screw disposed of into the pubic symphysis can better control the inner fracture end of the pubic branch to help its reduction and fixation. However, we still lack comparative studies, and the next step will involve conducting biomechanical or prospective research to validate them. Superficial infection of the suprapubic symphysis incision in one patient in this study occurred in the early stages of M-INFIX technological application. It may be related to the following reasons: lack of surgical experience, poor direction of screw placement leading to high tension in the skin incision and delayed wound healing causing infection.
This study has several limitations that should be considered when interpreting the results. First, the retrospective and single-center nature of the study introduces the potential for selection bias. The inclusion of patients was non-randomized, and the decision to use M-INFIX was at the surgeons' discretion. This may have led to the selection of patients with more favorable anatomy or less severe comorbidities, potentially overestimating the positive outcomes and limiting the generalizability of our findings to a broader patient population. Second, and most importantly, the absence of randomization and a control group (e.g., patients treated with plate fixation) prevents us from establishing causal inferences regarding the superiority of M-INFIX. The favorable results observed may be confounded by unmeasured variables such as specific patient characteristics or surgeon expertise. Therefore, our findings should be interpreted as evidence of the technique's feasibility and safety rather than its definitive advantage over existing methods. Furthermore, the relatively small sample size may have limited the power to detect rare complications. Despite these limitations, we believe this study provides valuable preliminary evidence and a detailed technical description for M-INFIX. Future multi-center, prospective, randomized controlled trials are warranted to minimize bias and directly compare the efficacy and safety of M-INFIX with traditional fixation techniques.
Conclusions
In conclusion, the findings of this retrospective study preliminarily indicate that the M-INFIX is a promising, minimally invasive treatment option for pubic symphysis diastasis. The technique demonstrated satisfactory radiographic reduction, excellent functional recovery, and a low complication rate in our patient cohort. However, it is important to emphasize that the retrospective design and relatively small sample size limit the generalizability of these findings. Therefore, the exact efficacy and comparative advantages of M-INFIX warrant further validation through larger-scale, prospective, randomized controlled studies.
Acknowledgements
Not applicable.
Statements All methods were performed in accordance with the relevant guidelines and regulations.
Abbreviations
- INFIX
Internal fixator
- M-INFIX
Modified internal fixator
- LFCN
Lateral femoral cutaneous nerve
- PSD
Pubic symphysis diastasis
- AIIS
Anterior inferior iliac spine
Authors’ contributions
Min Wu and Longfei Ye designed the study. Xiaopan Wang and Xiaotian Chen collected and analyzed the patient data. Min Wu and Jianzhong Guan performed the operation. Min Wu, Longfei Ye and Peishuai Zhao analyzed the results and prepared the manuscript. All authors read and approved the final manuscript.
Funding
The current study was supported by Anhui Province financial support key projects (no. AHWJ2023A10086).
Data availability
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.
Declarations
Ethics approval and consent to participate
This study was performed according to the Helsinki declaration and the study was approved by the ethics committee of Bengal Medical College (Number: BYYFY-2021190), and all subjects gave informed consent.
Consent for publication
Patients signed informed consent regarding publishing their data and photographs.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.