Single-Window Versus Two-Window Posterolateral Approach for Malleolar Fractures

Official title

Comparison of Single-Window and Two-Window Posterolateral Approaches in Posterior and Lateral Malleolus Fractures: A Clinical Outcomes Analysis

Overview

The purpose of this prospective clinical trial is to compare the clinical outcomes and early wound complication rates of two different surgical techniques used during the posterolateral approach for ankle fractures. Participants with fractures involving the posterior and lateral malleoli will undergo surgery using either a single-window technique (using a posterior antiglide plate) or a two-window technique (using a lateral anatomic plate). The main question the study aims to answer is whether the single-window approach reduces soft-tissue complications by minimizing surgical dissection, without compromising fracture stability. Patients will be followed for 12 months to assess wound healing, ankle range of motion, implant irritation, and functional recovery.

Detailed description

Ankle fractures involving the posterior malleolus are complex injuries that require anatomical reduction and stable fixation to prevent post-traumatic osteoarthritis. The posterolateral surgical approach allows direct visualization and fixation of both the posterior and lateral malleoli through a single incision. However, the optimal deep dissection technique and fibular plating strategy remain controversial.

The traditional two-window technique involves creating one interval medial to the peroneal tendons for posterior malleolus fixation, and a second interval lateral to the peroneal tendons to apply a standard lateral anatomic plate to the fibula. Alternatively, the single-window technique utilizes only the interval medial to the peroneal tendons to fix both malleoli, utilizing a posterior antiglide plate for the fibula.

This prospective study aims to compare the clinical and functional outcomes of these two techniques. The primary hypothesis is that the single-window approach with posterior antiglide plating will significantly minimize soft-tissue stripping, thereby reducing the incidence of early wound complications and late implant-related irritation, while providing excellent biomechanical stability against external rotation forces.

Patients with acute, closed ankle fractures involving both the distal fibula and the posterior malleolus will be included. To avoid confounding variables and methodological bias, patients demonstrating persistent syndesmotic instability that requires additional trans-syndesmotic fixation (screws or buttons) will be excluded from the study, as the single-window approach inherently restricts direct lateral access for such procedures. Clinical evaluations will include the assessment of early wound complications (dehiscence, necrosis, infection) within the first 3 months, as well as functional outcomes using the American Orthopaedic Foot and Ankle Society (AOFAS) score, range of motion, and Visual Analog Scale (VAS) for pain at 6 and 12 months postoperatively.

Interventions

• Procedure Posterior Antiglide Plating
  Fixation of the fibular fracture utilizing a posterior antiglide plate configuration applied directly to the posterior surface of the fibula.
• Procedure Lateral Anatomic Plating
  Fixation of the fibular fracture utilizing a standard lateral anatomic plate configuration applied to the lateral surface of the fibula.

Primary outcome measures

• Incidence of Wound Complications [Time frame: Up to 3 months postoperatively]

Secondary outcome measures (3)

• American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score [Time frame: 6 and 12 months postoperatively]
• Ankle Range of Motion (ROM) [Time frame: 12 months postoperatively]
• Visual Analog Scale (VAS) for Pain [Time frame: 6 and 12 months postoperatively]

Eligibility criteria

Inclusion criteria

• Patients aged between 18 and 65 years.
• Diagnosis of an acute, closed, unstable rotational ankle fracture with concomitant involvement of the posterior malleolus and lateral malleolus (trimalleolar or bimalleolar equivalent fractures).
• Fracture morphology explicitly indicating surgical reduction and internal fixation via a posterolateral approach (e.g., Bartonicek Type II, III, or IV).
• Ability to provide informed consent and willingness to comply with the 12-month postoperative rehabilitation and follow-up protocol.

Exclusion criteria

• Open fractures, severe tibial pilon variants, or fractures with intra-articular comminution extending beyond the posterior malleolus.
• Persistent Syndesmotic Instability: Patients demonstrating persistent distal tibiofibular syndesmotic instability (confirmed by intraoperative hook test) after the fixation of the posterior and lateral malleoli, which inherently requires additional trans-syndesmotic fixation (e.g., syndesmotic screws or suture-button devices). This exclusion is strictly applied to eliminate methodological bias, as the experimental single-window approach intentionally restricts direct lateral access for trans-syndesmotic interventions.
• Delayed surgical intervention exceeding 7 days from the initial trauma, leading to organized hematoma or compromised soft-tissue envelopes.
• Pre-existing conditions detrimental to soft-tissue healing and functional assessment, including severe peripheral arterial disease, uncontrolled diabetes mellitus with neuropathy, or severe ipsilateral ankle osteoarthritis.
• Previous history of ipsilateral ankle fractures or surgeries.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Turkey (Türkiye) · 1 center

• Ankara Bilkent City Hospital — Ankara

Publications

• Herbosa CG, Leucht P, Egol KA, Tejwani NC. The 2-Window Posterolateral vs Single-Window Approach for Ankle Fracture Fixation. Foot Ankle Int. 2023 Apr;44(4):297-307. doi: 10.1177/10711007231156163. Epub 2023 Mar 22. PMID 36946551
• Deng Y, Staniforth TL, Zafar MS, Lau YJ. Posterior Antiglide Plating vs Lateral Neutralization Plating for Weber B Distal Fibular Fractures: A Systematic Review and Meta-analysis of Clinical and Biomechanical Studies. Foot Ankle Int. 2022 Jun;43(6):850-859. doi: 10.1177/10711007221079617. Epub 2022 Apr 2. PMID 35373597
• Gu Y, Zhao L, Ren Y, Wang Y, Xu C, Jiang C. Modified Posterolateral Approach for the Treatment of 2-Part Fractures of the Posterior Malleolus Associated with Medial and Lateral Malleolar Fractures: 1 Incision, 2 Windows, 3 Steel Plates. Med Sci Monit. 2022 May 28;28:e936039. doi: 10.12659/MSM.936039. PMID 35633024

Identifiers

NCT: NCT07481266 · TABED 1-24-14

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗