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CompletedNCT02998333CAISRUpdated Oct 3, 2025

Chronic Ankle Instability, Surgical Repair: Open Versus Closed

An interventional study of Surgical stabilization in Chronic Ankle Instability, sponsored by Gwendolyn Vuurberg. Completed at 3 sites in 3 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-10-03.

Sponsored by Gwendolyn Vuurberg · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
41
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

Rationale: Lateral ankle ligament injuries may be a result of ankle sprains. In 10-30% of patients with lateral ankle ligament injuries, chronic lateral ankle instability may be present. If conservative treatment fails, instability is treated surgically. Anatomic repair (also known as the Bröstrom procedure) is the current golden standard for surgical treatment of chronic ankle instability. The Bröstrom started out as an open technique and is now also performed arthroscopically. Both approaches are considered standard care and provide good results. Which approach is best, has not yet been researched. In this study it is hypothesized arthroscopic repair provides better functional outcome compared to open repair during short term follow-up.

Objective: The main objective of this study is to compare the functional outcome after arthroscopic and open anatomic repair in patients with chronic lateral ankle instability, and secondly to assess ankle stability and ankle Range of Motion (ROM) after arthroscopic and open ligament repair.

Study design: A Non-Blinded Prospective Randomized Controlled Trial Study population: All patients willing to participate, from an age of 18 years old, with persisting ankle instability for at least 6 months, eligible for anatomic repair.

Intervention: Both groups of patients are surgically treated with anatomic repair of the anterior talofibular ligament (ATFL). One group is treated arthroscopically and the other by the open approach.

Main study parameters/endpoints: The primary outcome measure is functional outcome 6 months after surgery measured using the Foot and Ankle Outcome Score. The main study parameter is a difference of ≥10 2 points per FAOS subscale between both treatment groups (Minimal Important Change = 10 points; 2 per subscale).

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Conditions studied

  • Chronic Ankle Instability

Keywords

  • Instability
  • Ankle
  • Surgical stabilization
03

In context

Lead sponsor

This is the only study on the registry with Gwendolyn Vuurberg as lead sponsor.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Patients are 18 years or older;
  • Experience pain and/or a sensation of instability during sports and/or daily activity;
  • Isolated lateral ankle instability;
  • Planned for surgical repair of the ATFL;
  • At least one previous episode of an ankle inversion sprain;
  • Complaints for at least 6 months;
  • Failed previous conservative treatment.

Exclusion criteria

Exclusion Criteria:

  • Serious concomitant injury (like arthrosis, ruled out using an AP and lateral x-ray according to standard protocol);
  • Foot or ankle fracture in past;
  • Previous foot or ankle surgery;
  • ROM restriction of >10 degrees;
  • Medial instability;
  • Severe misalignment;
  • Ankle/foot deformities (e.g. severe flat foot);
  • Systemic comorbidity leading to delayed recovery (e.g. Diabetes Mellitus, Rheumatoid Arthritis)
  • (general) Hyper laxity
  • Inability or unwillingness to provide consent
  • Present factors that may cause difficulty of follow-up
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Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Outcomes assessor)
Enrollment
41 participants (actual)

Study arms

  • Active comparator
    Open surgical ankle stabilization

    These patients will receive open surgical stabilization of the ankle joint after failed conservative treatment with complaints for at least 6 months.

    Procedure: Surgical stabilization

  • Active comparator
    Arthroscopic surgical ankle stabilization

    These patients will receive arthroscopic surgical stabilization of the ankle joint after failed conservative treatment with complaints for at least 6 months.

    Procedure: Surgical stabilization

Interventions

  • ProcedureSurgical stabilization

    Surgical stabilization of the ankle joint, performed as an open or arthroscopic procedure.

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What researchers measure

Primary outcomes

  1. Functional outcome

    The primary outcome measures is a difference in pain and disability between both treatment groups as measured a Functional Ankle Outcome Score (FAOS) score change of ≥2 points per subscale measured at 6 months follow-up.

    Time frame: 6 months

Secondary outcomes

  1. Functional outcome FAOS

    For assessment disablement

    Time frame: 3- and 6 months

  2. Functional outcome Numeric Rating Scale (NRS) pain

    For pain assessment

    Time frame: 3- and 6 months

  3. Functional outcome Cumberland Ankle Instability Tool (CAIT)

    For instability assessment

    Time frame: 3- and 6 months

  4. Anterior Drawer Test (ADT)

    The anterior drawer test is registered per mm (range 0-15mm) displacement and according to the manual anterior drawer test (M-ATT) categories (grade 0-3).

    Time frame: Pre-operative, instraoperative, 3- and 6 months postoperative

  5. Range of Motion (ROM)

    ROM is registered in degrees of dorsi- and plantarflexion and is measured using a goniometer. Assessment is performed pre-operatively, and at 3- and 6-months postoperatively.

    Time frame: Pre-operative, instraoperative, 3- and 6 months postoperative

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Study locations

3 sites
  • AMC
    Amsterdam, 1105 AZ, Netherlands
  • Centro Hospitalar Povoa deVarzim
    Porto, Portugal
  • Site Hôpital orthopédique
    Lausanne, Switzerland
08

References and documents

Publications

  • Kobayashi T, Gamada K. Lateral Ankle Sprain and Chronic Ankle Instability: A Critical Review. Foot Ankle Spec. 2014 Aug 1;7(4):298-326. doi: 10.1177/1938640014539813. Epub 2014 Jun 24. PubMed 24962695 ↗
  • Brostrom L. Sprained ankles. VI. Surgical treatment of "chronic" ligament ruptures. Acta Chir Scand. 1966 Nov;132(5):551-65. No abstract available. PubMed 5339635 ↗
  • Mabit, C.C., J.M.; Fiorenza, F.; Huc, H.; Pecout, C., Lateral ligament reconstruction of the ankle: comparative study of peroneus brevis tenodesis versus periosteal ligamentoplasty. Foot and Ankle Surgery, 1998. 4(2): p. 6.
  • Pereira H, Vuurberg G, Gomes N, Oliveira JM, Ripoll PL, Reis RL, Espregueira-Mendes J, Niek van Dijk C. Arthroscopic Repair of Ankle Instability With All-Soft Knotless Anchors. Arthrosc Tech. 2016 Feb 1;5(1):e99-e107. doi: 10.1016/j.eats.2015.10.010. eCollection 2016 Feb. PubMed 27073785 ↗
  • Drakos MC, Behrens SB, Paller D, Murphy C, DiGiovanni CW. Biomechanical Comparison of an Open vs Arthroscopic Approach for Lateral Ankle Instability. Foot Ankle Int. 2014 Aug;35(8):809-815. doi: 10.1177/1071100714535765. Epub 2014 May 21. PubMed 24850160 ↗
  • Matsui K, Takao M, Miyamoto W, Matsushita T. Early recovery after arthroscopic repair compared to open repair of the anterior talofibular ligament for lateral instability of the ankle. Arch Orthop Trauma Surg. 2016 Jan;136(1):93-100. doi: 10.1007/s00402-015-2342-3. Epub 2015 Oct 14. PubMed 26467354 ↗
  • Vuurberg G, Maria PA, Baalbaki R, Haverkamp D, Sierevelt IN, Stufkens SAS, Pereira H, M M J Kerkhoffs G; CAISR Trial Study Group; Altink NA, van Bergen CJA, Blankevoort L, Crevoisier X, van Dijk CN, Hoornenborg D, Krips R, de Leeuw PA, Peerbooms JC, Reilingh ML, Sousa D, Stanekova K. No Difference Between Open and Arthroscopic ATFL Repair, Both Yielding Clinically Significant Improvement in Chronic Ankle Instability: A Randomized Controlled Trial. Orthop J Sports Med. 2026 Apr 8;14(4):23259671261417357. doi: 10.1177/23259671261417357. eCollection 2026 Apr. PubMed 41970204 ↗

Individual participant data

Plan to share: No

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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Oct 3, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT02998333
Lead sponsor
Gwendolyn Vuurberg
Collaborators
Zimmer Biomet, Centro Hospitalar do Porto, Site Hôpital orthopédique, Amphia Hospital, Albert Schweitzer Hospital
Responsible party
Gwendolyn Vuurberg (PhD Candidate, Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)) — Sponsor-investigator
First posted
Dec 20, 2016
Start date
Jan 2017
Primary completion
Jan 2025
Completion
Mar 2025
Last update
Oct 3, 2025

Study contacts

G.M.M.J. Kerkhoffs, Professor
principal investigator · Department of Orthopaedic Surgery, AMC, Amsterdam, The Netherlands

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Oct 2025. You cannot join it, but the record below documents what was studied.

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