Patient selection
This study was approved by our University’s Research Ethical Committee on January 19, 2021, under decision (E-54022451-050.01.04-4100). At our institution, medical charts of patients diagnosed with an acetabular fracture were reviewed retrospectively. Informed consent was obtained from all individual participants included in the study. Patients who underwent surgical intervention with the mSA between 2012 and 2020 were selected as core samples of this study.
The inclusion criteria were as follows: radiologically diagnosed with an acetabular fracture, experience surgical intervention with the mSA at our department, no age restriction, operated within two weeks of trauma, consent for study participation and surgical intervention, and regular follow-up visits for at least one year.
The exclusion criteria were as follows: received a total hip replacement (n = 2), to avoid confusion that may affect the outcomes related to the delayed operation, the neglected fractures (operated after two weeks of trauma) (n = 2), isolated posterior acetabular fracture (n = 1), history of previous Caesarean section, bladder injury, hysterectomy, bladder surgery or prostatectomy (n = 2), the presence of multiple traumas causing delayed immobilisation, such as head traumas or avascular necrosis of the femoral head in the early period (n = 3), lost to follow-up for any reason (n = 2), and rejected participation (n = 1).
Preoperative assessment and preparation
All patients were subjected to complete systemic examinations in the emergency room. A urinary catheter was implanted in the case of genitourinary system injury. The appropriate departments were consulted in the presence of other organ traumas. If the systemic conditions of the patients permitted, pelvic and Judet (anteroposterior pelvic, iliac and obturator oblique) radiographs and computerised tomography scans were ordered. We classified the fracture types based on the criteria of Judet et al. [11]. At this stage, we evaluated the patients for surgical indication and timing regarding the following factors: fracture displacement (>2 mm), fracture type, hip instability, the presence of intra-articular fragments, patient's age, existing additional injuries and clinical condition.
Low molecular weight heparin was started at the time of admission for deep vein thrombosis prophylaxis. It was stopped on a postoperative day 30. Preoperative antibiotic prophylaxis was administered one hour before the incision and continued to prevent surgical site infection. It was stopped on a postoperative day 3.
Surgical technique
All patients were operated on by a senior orthopedist using the mSA. The patient was positioned supine on the operating table while C-arm fluoroscopy was used to assess the fracture's reducibility. The orthopedist stood up on the contralateral side of the acetabular fracture. Under sterile conditions, the hip was held in the flexion while the knee was supported with a big sandbag to relax the abdomen, iliopsoas muscle and external iliofemoral neurovascular bundle. Thus, the surgeon facilitates fracture reduction by enabling multi-directional traction of the limbs. At 2 cm proximal to the superior pubic ramus, a 10-cm Pfannenstiel or vertical incision was made. The rectus abdominis muscle and the linea alba were separated to medialise the internal aspect of the pelvis. To expose the fracture fragments, corona Mortis was initially identified and ligated before subperiosteal dissection. The iliopsoas muscle was retracted upward, noting the obturator and external iliac neurovascular bundles. Once the fracture site was exposed, the reduction was completed and internal fixation was performed. Fixation was performed in all patients using a 3.5-mm pelvic reconstruction plate and screws (Fig. 1).
Postoperative follow-up protocol and outcome assessment
Perioperative data, such as estimated intraoperative blood loss (EBL) and fracture types, accompanying injuries and surgical-related complications, were analysed. On the first postoperative day (POD1), patients whose general condition permitted it, were mobilised on double crutches without weight-bearing under the supervision of a physiotherapist. The weight was increased according to the clinical and radiological data.
The radiological assessment was conducted by a radiologist who was not aware of the results. An orthopedist performed a functional assessment. Postoperatively, the quality of reduction was evaluated by calculating the maximum displacement of the bone fragment in millimetres on standard pelvic and Judet’s radiographs recorded on POD1. According to Matta's reduction criteria, reduction quality was evaluated as follows; 0–1 mm = anatomical reduction, 2–3 mm = imperfect, and >3 mm = poor [6].
The functional and radiographic evaluations were performed routinely on postoperative weeks two and six, months three, six, and twelve. The patients were thereafter monitored each year. We evaluated the radiological outcomes using Matta’s radiological staging system. The normal radiological view was considered an excellent radiological result. Slight alterations in the joint, such as small osteophytes, minimal narrowing (1mm) and minimal sclerosis, were considered as good, moderate changes as fair and advanced changes as poor [6]. We performed the functional assessment using Merle d'Aubigné (MDAS), Harris hip score (HHS) and Short Form 12 (SF-12) scores at the last control visits [1-3]. We measured the operated joint ranges of motion at the last control visits.
Statistical data
We used SPSS 20.0 (IBM, Armonk, NY, USA) to analyse the collected data. Descriptive statistical analyses were used to evaluate demographics, clinical and functional data. Further, we compared proportional data according to fracture type using the Fisher exact X2 test. Fracture type, Matta’s reduction quality and surgical outcomes were compared using the Mann–Whitney U test. Pearson’s (for normally distributed data) or Spearman’s (for ordinal data) correlation analysis was used to evaluate the correlations between continuous variables. The significance level was determined at a p-value of <0.05. Two-tailed tests were used.