OPEN Research Support

Clinical Assistant
Rune Sort
Department of anaesthesiology, Herlev Hospital

Projekt styring
Projekt status    Sampling ongoing
Data indsamlingsdatoer
Start 15.06.2015  
Slut 01.10.2017  

AnAnkle Trial: Peripheral nerve block vs. Spinal anaesthesia for ankle fracture surgery - implications on pain profile and quality of recovery

Short summary

Ankle fracture surgery is a very common procedure for which different anaesthesia modalities are available. In recent years peripheral nerve block (PNB) has become increasingly popular and evidence indicates a benefit on the postoperative pain profile, when using PNB in planned orthopedic procedures. However, rebound pain upon cessation of the PNB has been indicated to pose a clinical problem after fracture surgery. AnAnkle Trial is a randomized controlled trial of 150 patients comparing postoperative pain profiles and quality of recovery in ankle fracture surgery using PNB versus Spinal anaesthesia to investigate whether PNB is beneficial for this patient group.


In recent years peripheral nerve block (PNB) has become increasingly popular as a method of anesthesia for acute orthopedic surgery such as fixation of fractures. The long lasting effect of PNB makes it attractive for postoperative pain control. Current evidence supports this by indicating a benefit on the postoperative pain profile including pain scores, morphine consumption and opioid side effects, when using PNB in planned orthopedic procedures. However, the pain profile in acute conditions such as fractures is naturally different from that in planned surgery. Furthermore, rebound pain upon cessation of the PNB has been indicated to pose a clinical problem after ankle fracture surgery.

Ankle fractures are very common and surgery often indicated. A variety of different anaesthesia modalities are used for this procedure including PNB. Therefore the aim of AnAnkle Trial is to establish whether PNB has the same benefits in ankle fracture surgery as in planned surgery - despite the possibility of rebound pain.

Description of the cohort

AnAnkle Trial is performed in Region Hovedstaden and is based at Herlev Hospital, Copenhagen University. We consecutively include 150 patients in total from Herlev and Hvidovre Hospitals.

Inclusion criteria: over 18 years old, booked for internal fixation of an ankle fracture and fluent in Danish language (Danish questionnaires).

Key exclusion criteria: Relevant allergies, contraindications for spinal or PNB anesthesia, other fractures/pains, habitual opioid use, neuropathy, dialysis, cognitive/psychiatric dysfunction with expected compliance problems, pregnancy and failure to provide informed, written consent. 

Data and biological material

Primary outcome data:

  • Pain scores (NRS 0-10 every 3 hours for 27 hours after administration of anesthesia).
  • Morphine consumption (27 hors post anesthesia) in mg i.v.

Secondary/tertiary outcome data:

  • Opioid adverse effects (OR-SDS score).
  • Quality of recovery (QoR-15 score).
  • Patient satisfaction (NRS score).
  • Daily pain scores (NRS) postoperative day 1-7.
  • Daily morphine consumption (no. of tablets) postoperative day 1-7.
  • Adverse events.
  • Perioperative nerve symptoms on day 7.

Background data:

Gender, age, height, weight, ASA physical score, comorbidities, diabetic status, habitual weekly alcohol consumption, smoking, habitual non-opioid pain medication, habitual use of sedatives, type of fracture, dislocation of the ankle (i.e. necessity of initial immediate closed reduction), number of surgical incisions, time points for surgery, time of trauma, time of admission and release from orthopaedic ward, surgical wound infection (i.e. prescribed antibiotics for wound infection on day 2-7).

These data can potentially influence the selected outcomes and are collected for analysis of such influence.

Collaborating researchers and departments

Department of Anaesthesiology, Herlev Hospital, Copenhagen University

  • Sponsor and coordinating investigator Rune Sort, MD
  • Medical research advisor and Professor Ann Merete Møller, MD, DMSc
  • Sub-investigator and Consultant Anaesthesiologist Jesper Kent Nielsen, MD
  • Research assistant Lasse Lykkebo Olsen,

Department of Orthopaedic Surgery, Herlev Hospital

  • Medical research advisor Stig Brorson, MD, PhD, DMSc
  • Sub-investigator and Specialist Registrar Nanna Salling, MD

Department of Surgery, Roskilde/Køge Hospital

  • Medical research advisor and Professor Ismail Gögenur, MD, DMSc

Department of Anaesthesiology, Hvidovre Hospital

  • Medical research advisor Nicolai Bang Foss, MD, DMSc
  • Consultant Anaesthesiologist Sine Hougaard, MD

Department of Orthopaedic Surgery, Hvidovre Hospital

  • Sub-investigator and Specialist Registrar Peter Toft Tengberg, MD, PhD

GCP unit of Copenhagen University Hospital, Bisbebjerg Hospital

  • GCP monitor Inge-Caroline Wiuff

OPEN Odense Patient data Explorative Network, Odense University Hospital

  • Data manager Erik Holm-Petersen