A Trial of Plate Fixation Versus Tension Band Wire for Olecranon Fractures
Condition: Displaced Olecranon Fractures
MeSH terms: Fractures, Bone; Olecranon Fracture; Ulna Fractures
Study type: Interventional

Summary: 
      Proximal forearm fractures comprise approximately 5% of all fractures, with olecranon
      fractures accounting for almost 20% of thes fractures. There is limited conclusive evidence
      regarding the optimal treatment and outcome of these fractures with only one prospective
      randomized trial (1992) in the literature comparing tension band wire and plate fixation for
      displaced olecranon fracture. Our trial includes all patients under the age of 75yrs
      presenting to the Edinburgh Orthopaedic Trauma Unit with an isolated olecranon fracture
      requiring operative intervention. Patients who consent to enrol in the trial will be
      randomised to operative fixation using one of two recognised fixation techniques - tension
      band wire fixation or plate fixation. Patients will be evaluated over a one year period
      following their surgery.
    

Detailed description: 
      Background

      Proximal forearm fractures comprise approximately 5% of all fractures, whilst olecranon
      fractures account for almost 20% of fractures occurring around the elbow1. There is limited
      conclusive evidence regarding the epidemiology, optimal treatment and outcome of isolated
      olecranon fractures.

      Patients with undisplaced olecranon fractures can be treated non-operatively2,3. The aims of
      treatment in displaced olecranon fractures are the restoration of function and stability to
      the elbow joint4. The technique employed should allow preservation and reconstruction of the
      articular surface with minimal associated complications. Tension-band wiring (TBW) is the
      most recognised and commonly used fixation method, although plate fixation and intramedullary
      screw fixation are noted alternatives2,4-10. Potential problems with the TBW technique are
      wound breakdown, infection, prominent metalwork, malunion and non-union2,4,7,11-13.
      Furthermore, plate fixation is considered to be superior in distal/comminuted/oblique
      fractures and fracture-dislocations, with superior fracture reduction and fixation results,
      as well as a lower rate of re-operation2,5,13,14. There is only one prospective randomized
      trial in the literature comparing TBW and plate fixation for displaced olecranon fracture13.
      The major conclusions from this study were:

        -  The functional outcome at six months was not significantly different in the two groups

        -  Post-operative loss of fracture reduction (53% vs 5%) and prominent symptomatic
           metalwork was more frequently observed after TBW

      This study was performed in 1992 with less sophisticated plates when compared with the
      location specific plates currently available.

      Research Aim

      To determine if any difference exists in outcome (primary measure - DASH score) after one
      year between open reduction and internal fixation with tension band wiring AND plate and
      screw fixation for olecranon fractures.

      Methodology

      This trial involves identifying patients under the age of 75yrs (<75yrs) presenting to the
      Edinburgh Orthopaedic Trauma Unit with an isolated olecranon fracture requiring operative
      intervention. Patients who consent to enrol in the trial will be randomised to one of two
      recognised operative fixation techniques - tension band wire fixation or plate fixation. The
      trial will commence once ethical approval is granted by the Lothian Research Ethics
      Committee.

      All statistical analysis was/will be performed by Dr Rob Elton. Prior to the study a power
      analysis determined the number of patients required in each trial. The primary outcome
      measure will be the DASH score, a continuous variable that follows a normal (Gaussian-shaped)
      distribution. This study is designed to determine a clinically relevant mean difference of 10
      points between the two cohorts at one year after enrolment. A power analysis indicated that a
      total sample size of 50 (25 in each group) subjects will provide 80% statistical power to
      detect significant differences (0.05) in DASH scores, assuming an effect size of 0.8 (mean
      difference of 10 points, standard deviation of 12 points) using an unpaired t-test. To
      account for a possible loss to follow-up of up to 25%, we anticipate enrolling 35 subjects in
      each cohort for a total sample size of 70 subjects. A p value of < 0.05 was considered
      statistically significant.

      All adult patients presenting to the Edinburgh Orthopaedic Trauma Unit with a fracture of the
      olecranon that satisfy the inclusion criteria will be invited to participate in our study.
      All adult patients with an olecranon fracture best treated operatively are eligible for
      enrolment in this study regardless of sex, race or ethnicity. Vulnerable populations will not
      be recruited.

      A qualified member of the on-call team will introduce the study to the patient and initiate
      informed consent. If the patient agrees, a research fellow (Trauma and Orthopaedic StR3
      level), not involved with the patient's care will review the study protocol in detail and
      address any questions the patient may have. If the patient is willing to participate, the
      research fellow will complete the informed consent. Patients will be given a copy of the
      consent form, and be informed that their participation is voluntary and that they can
      withdraw at any time during the study without detriment to their normal care in any way.
      Patients may take as long as they like to consider participation, provided that they still
      meet all the eligibility criteria documented above. Patients that are willing to participate
      in this study will get the same care of their fracture as patients that decide not to
      participate in the study.

      On enrolment, a data collection form will be started with demographic and injury-related
      information collected. Prior to surgery, patients will be randomised (performed by Dr Rob
      Elton using closed opaque envelopes) into one of the two groups (tension band wire fixation
      or plate fixation). Following surgery, the post-operative assessment and course will be as
      per normal protocol for patients who are not in this study. Patients will be immobilised
      depending on fracture fixation during surgery and the decision will be made by the treating
      surgeon. Physiotherapy will be arranged when required

      Follow-up All follow-up assessment will take place during follow-up visits initially with the
      treating consultant surgeon's team and a dedicated research physiotherapist. Radiographs and
      other diagnostic studies will be obtained at the discretion of the treating surgeon and will
      not differ from routine clinical care.

      Follow-up assessment will be collected over a one year period (2 weeks, 6 weeks, 3 months, 6
      months and one year). Routine follow-up in our institution for patients who have sustained an
      olecranon fracture that is managed operatively involves outpatient clinic reviews with
      radiographs at 2 weeks, 6 weeks, three months and six months. Therefore, one additional visit
      at 1 year is required for this study with no additional radiographs. Radiographs will only be
      performed at one year on clinical indication.

      At each visit physical examination, treatment, complications and re-operation (e.g. hardware
      removal), for each patient will be recorded. A research physiotherapist, blinded to the
      treatment method by sticking plaster over the entry position, will undertake functional
      testing and assessment.

      Outcome and statistical methods By statistically analysing the outcome scores in the two
      groups, I aim to better determine the optimal management of this fracture in this age group.
      Using univariate analysis and multivariate regression analysis I will determine significant
      (p<0.05) predictors of outcome in relation to functional outcome score (DASH at one year).
    

Intervention name(s): Tension Band Wiring; Plate fixation
Intervention type(s): Procedure; Procedure
Intervention description(s): AO technique of TBW for fixation of fracture.; Patients in this arm will receive plate and screw fixation of their olecranon fracture.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment