Fixation of the Posterior Malleolus in Trimalleolar AO Weber C Fractures. (POSTFIX-C)

Operative Treatment of AO Weber C Fibular Fractures With Additional Medium-sized Posterior Malleolar Fragment: Syndesmotic Reduction and Functional Outcome After Syndesmotic Positioning Screws or Posterior Fragment Fixation. POSTFIX-C Trial: a Prospective Comparative Observational Study.

In AO Weber type C fractures, there is a combination of a proximal fibular fracture, a medial fracture or ruptured deltoid ligament, and a syndesmotic injury. Anatomical repair and reduction of the syndesmosis is essential to prevent diastasis in the ankle-joint. Widening and chronical instability of the syndesmosis is related to worse functional outcome and development of posttraumatic osteoarthritis in the ankle. There is limited biomechanical and clinical evidence that syndesmotic stability in AO Weber type C fractures with an additional posterior malleolar fracture can also be reached by fixation of the posterior malleolar fragment. Maybe, this is even superior to the usual treatment with syndesmotic positioning screws. Some authors concluded that stability of the syndesmosis in these fractures can be much more achieved by fixation of the posterior malleolar fragment than by placement of syndesmotic positioning screws alone. Another additional benefit of open reduction and fixation of the posterior malleolar fragment is that this will lead to an anatomical reconstruction of the syndesmosis. Although there is no current evidence, it is likely that a malreduction of the fibula in the tibial incisura will lead to a worse functional outcome on the long-term. No clear consensus in the literature is found as to which fragment size of the posterior malleolus should be internally fixed. The general opinion is that displaced fragments that involve more than 25% of the distal articular tibia should be fixed. Traditionally, reduction of these larger fragments is indirectly, followed by percutaneous screw fixation in anterior-posterior direction. Disadvantages are that it is hard to achieve an anatomical reduction, and that percutaneous fixation of smaller fragments is very difficult. Recently, a direct exposure of the posterior tibia via a posterolateral approach in prone position, followed by open reduction and fixation with screws in posterior-anterior direction or antiglide plate is advocated by several authors. This approach allows perfect visualization of the fracture, articular anatomical reduction, and strong fixation. Another advantage is that even small posterior fragments can be addressed. Several case series are published, which describe minimal major wound complications, good functional outcomes, and minimal need for reoperation.

Study Overview

• Status: Unknown
• Conditions: Trimalleolar Fracture; AO Weber C Fractures; Syndesmotic Stability; Open Reduction and Internal Fixation
• Intervention / Treatment: Device: Fixation; Device: NO Fixation

• Study Type: Observational
• Enrollment (Anticipated): 54

Contacts and Locations

• Study Contact: Name: Sander Verhage, Drs.; Phone Number: +31644847448; Email: sanverhage@hotmail.com

Study Locations

• Netherlands
  • Zuid-Holland
    • Leiden, Zuid-Holland, Netherlands
      • Not yet recruiting
      • Leiden University Medical Center
      • Contact: Sander Verhag, Drs.; Phone Number: +31644847448; Email: sanverhage@hotmail.com
    • The Hague, Zuid-Holland, Netherlands, 2512VA
      • Recruiting
      • MCHaaglanden
      • Contact: Sander Verhage, Drs.; Phone Number: +31644847448; Email: sanverhage@hotmail.com
    • The Hague, Zuid-Holland, Netherlands
      • Recruiting
      • Bronovo Ziekenhuis
      • Contact: Sander Verhage, Drs.; Phone Number: +31644847448; Email: sanverhage@hotmail.com
    • The Hague, Zuid-Holland, Netherlands
      • Not yet recruiting
      • Haga ziekenhuis
      • Contact: Sander Verhage, Drs.; Phone Number: +31644847448; Email: sanverhage@hotmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 68 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

All patients presenting with a trimalleolar AO-Weber C fracture with additional posterior fragment (5-25% of the involved articular surface, AO type 44-C1, 44-C2, 44-C3) in the participating hospitals between the age of 18 and 70 could be included in our study.

Description

Inclusion Criteria:

1. Age between 18 and 70 years
2. First ankle fracture of the affected side
3. Isolated, fibular fracture proximal to the syndesmosis with a posterior malleolar fragment between 5 and 25% of the involved articular surface(AO type 44-C1, 44-C2, 44-C3).

Exclusion Criteria:

1. Multiple injuries
2. Ankle fracture of the same ankle in the history
3. Patients with pre-existent mobility problems
4. Pre-existent disability like wheelchair or walking aid dependency.
5. Patients living in another region of whom follow-up will take place in another hospital
6. Insufficient understanding of the Dutch language

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Fixation; Patients with a trimalleolar AO Weber C fracture with open reduction and fixation of the posterior malleolar fragment.	Device: Fixation; Fixation of the posterior malleolus with lag-screws or plate-fixation. If syndesmosis is intra-operatively stable, no syndesmotic positioning screws will be placed.
No Fixation; Patients with a trimalleolar AO Weber C fracture without open reduction and fixation of the posterior malleolar fragment.	Device: NO Fixation; Posterior malleolus will not be fixated. Syndesmotic positioning screws will be placed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Accuracy of syndesmotic reduction 1cm above the tibial plafond, measured on post-operative CT-scan in millimeters compared to the contralateral (healthy) side.	1 year
Functional outcome measured by AAOS score (special questionnaire for hindfoot and ankle in 27 questions.)	1 Year

Secondary Outcome Measures

Outcome Measure	Time Frame
Posttraumatic osteoarthritis defined by the Kellgren-Lawrence score (1-4)	5 Years

Collaborators and Investigators

• Sponsor: Medical Center Haaglanden
• Collaborators: Leiden University Medical Center

Study record dates

Study Major Dates

• Study Start: November 1, 2015
• Primary Completion (Anticipated): December 1, 2022

Study Registration Dates

• First Submitted: November 3, 2015
• First Submitted That Met QC Criteria: November 5, 2015
• First Posted (Estimate): November 6, 2015

Study Record Updates

• Last Update Posted (Estimate): September 13, 2016
• Last Update Submitted That Met QC Criteria: September 12, 2016
• Last Verified: September 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Wounds and Injuries; Fractures, Bone; Ankle Fractures
• Other Study ID Numbers: NL50169.098.15