Open Versus Minimally Invasive Fixation for Unstable Sacral Fractures in Adults

Open Versus Minimally Invasive Lumbopelvic Fixation in the Management of Traumatic Unstable Sacral Fractures in Adults: A Retrospective Cohort Study

Severe injuries to the lower spine and pelvis, known as traumatic unstable sacral fractures, are complex injuries that often require surgery to stabilize the bones and prevent long-term disability. A standard surgical treatment is lumbopelvic fixation, which uses metal screws and rods to connect the lower spine to the pelvic bones. This procedure can be performed using a traditional open surgical approach with a larger incision, or a minimally invasive approach using smaller incisions.

While both methods are used to effectively stabilize the fracture, there is a need for more comprehensive data comparing which approach provides the best overall recovery with the fewest complications.

The purpose of this retrospective study is to compare the long-term outcomes of adult patients who underwent open lumbopelvic fixation versus those who had minimally invasive lumbopelvic fixation. Researchers will review the medical records and imaging of patients treated between January 2016 and December 2024.

The main goal of the study is to evaluate physical function and recovery using a standardized assessment tool called the Majeed Pelvic Score. Additionally, the study will compare the two surgical groups to look at:

• Bone healing: How well the bones aligned and healed over time.
• Surgical complications: Rates of wound infections, skin issues, or hardware failures (like broken screws).
• Clinical recovery: Improvement in nerve function (for those who had pre-existing deficits) and post-surgery back pain levels.
• Quality of life: How quickly patients were able to return to work and perform their jobs efficiently.
• Secondary surgeries: The need for any additional operations following the initial fix.

By comparing these two approaches comprehensively, researchers hope to help surgeons identify the optimal surgical method tailored to a patient's specific fracture characteristics.

Study Overview

• Status: Not yet recruiting
• Conditions: Sacral Fractures; Traumatic Unstable Sacral Fractures; Spinopelvic Dissociation; Pelvic Ring Injuries

Detailed Description

Traumatic unstable sacral fractures are challenging high-energy pelvic injuries with significant implications for structural integrity and neurological function. While traditional open lumbopelvic fixation (O-LPF) provides excellent biomechanical stability and allows for direct neural decompression, it requires an extensile posterior approach associated with significant perioperative morbidity, including deep surgical site infection rates historically ranging from 16% to 26%. Minimally invasive or percutaneous lumbopelvic fixation (MIS-LPF) was developed to mitigate these approach-related complications, though it permits only indirect neural decompression.

Despite emerging evidence favoring MIS techniques for reduced blood loss and infection rates, most published series remain small, retrospective, and heterogeneous. This study aims to provide a comprehensive, multi-dimensional comparison of open versus minimally invasive lumbopelvic fixation specifically in adult patients with traumatic unstable sacral fractures.

This is a retrospective, comparative cohort study conducted at the Department of Orthopedic Surgery and Traumatology at Assiut University. Data will be systematically extracted by two independent investigators from electronic medical records, surgical operative logs, and PACS digital imaging systems for qualifying index surgeries performed between January 2016 and December 2024. A standardized data extraction sheet will be utilized to minimize observer bias, and all data will be de-identified prior to analysis.

Researchers will collect comprehensive data points across several domains:

• Baseline and Injury Characteristics: Demographics, comorbidities, mechanism of injury, and precise fracture classifications including Denis Zones, Roy-Camille, and AO/OTA.
• Surgical and Perioperative Details: Surgical technique utilized, operative time, estimated blood loss, specific implant details, use of intraoperative imaging, and length of hospital/ICU stay.
• Clinical and Radiological Outcomes: Neurological status documented via the Gibbons Neurological Grading Scale, quality of fracture reduction assessed via Matta and Tornetta criteria, time to radiographic union, and postoperative pain levels via Visual Analog Scale (VAS).
• Complications: Incidence of surgical site infections (superficial and deep), wound dehiscence, implant failure, thromboembolic events, and the necessity and timing of secondary reoperations.

• Study Type: Observational
• Enrollment (Estimated): 60

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult patients ($\ge$ 18 years) treated at the Department of Orthopedic Surgery and Traumatology at Assiut University. Patients must have a confirmed diagnosis of a traumatic, unstable sacral fracture (including Denis Zones I-III with instability, spinopelvic dissociation, or AO/OTA Type C injuries). All included subjects were operated on using either open or minimally invasive lumbopelvic fixation between January 2016 and December 2024. Furthermore, participants must have adequate medical records with a minimum of 12 months of postoperative clinical follow-up.

Description

Inclusion Criteria:

• Adult patients aged 18 years or older at the time of injury and surgery.
• Confirmed diagnosis of a traumatic, unstable sacral fracture, including: Denis Zone I, II, or III fractures with instability; Spinopelvic dissociation (U-type / H-type sacral fractures); AO/OTA Type C pelvic ring injuries involving the sacrum.
• Operated on using lumbopelvic fixation (open or minimally invasive technique) within the study period (2016-2024).
• Availability of adequate and complete medical records, including: Preoperative and postoperative imaging (X-ray and/or CT scan), and operative notes and surgical logs.
• Minimum clinical follow-up of 12 months postoperatively.

Exclusion Criteria:

• Pathological fractures (e.g., fractures secondary to primary or metastatic malignancy, osteoporotic insufficiency fractures).
• Patients managed conservatively or with alternative fixation strategies that do not include lumbopelvic instrumentation (e.g., isolated iliosacral screw fixation, anterior ring fixation alone).
• Severe polytrauma resulting in in-hospital mortality prior to the minimum required follow-up period.
• History of previous pelvic, sacral, or lumbosacral spine surgery prior to the index trauma.
• Incomplete medical records or inadequate radiological follow-up data preventing accurate assessment of outcomes.
• Patients with pre-existing neuromuscular disorders or spinal pathology that would confound neurological or functional outcome assessment.
• Pregnant patients at the time of injury

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Group A: Open Lumbopelvic Fixation (O-LPF); Adult patients with traumatic unstable sacral fractures who were managed surgically using an open lumbopelvic fixation technique.
Group B: Minimally Invasive Lumbopelvic Fixation (MIS-LPF); Adult patients with traumatic unstable sacral fractures who were managed surgically using a minimally invasive or percutaneous lumbopelvic fixation technique.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Majeed Pelvic Score (MPS)	Functional outcome will be assessed using the Majeed Pelvic Score (MPS). The MPS is a validated 100-point scoring system evaluating five parameters: pain (30 points), work capacity (20 points), ability to sit (10 points), sexual intercourse (4 points), and standing/walking (36 points). Higher scores indicate better functional recovery, with total scores graded as: Excellent (85 or higher), Good (70 to 84), Fair (55 to 69), or Poor (less than 55).	At final clinical follow-up, with a minimum of 12 months postoperatively.

Collaborators and Investigators

• Sponsor: Assiut University

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): June 1, 2027

Study Registration Dates

• First Submitted: April 10, 2026
• First Submitted That Met QC Criteria: April 10, 2026
• First Posted (Actual): April 16, 2026

Study Record Updates

• Last Update Posted (Actual): April 16, 2026
• Last Update Submitted That Met QC Criteria: April 10, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Majeed Pelvic Score; Lumbopelvic Fixation (LPF); Minimally Invasive Surgery (MIS); Percutaneous Lumbopelvic Fixation; Open Lumbopelvic Fixation; Sacral Laminectomy; Denis Classification; Roy-Camille Classification; Matta and Tornetta Criteria
• Other Study ID Numbers: Open vs MIS Sacral Fixation