Long-term results of the arthroscopic Bankart procedure

Anterior shoulder dislocations have an incidence between 21 and 27 per 100.000
person years. Recurrent instability develops in up to 25-46% of the patients
having experienced an anteriorly directed traumatic dislocation.
When the shoulder dislocates, lesions of the capsular ligaments, capsulolabral
structures and bony defects of the humeral head and glenoid rim are frequently
present. This may lead to recurrent instability symptoms when the arm is
brought into abduction and external rotation. If conservative treatment fails
or is not preferred, (arthroscopic) anterior shoulder stabilisation can be
performed using suture anchors to reattach the capsulolabral structures to the
glenoid (Bankart procedure). In spite of the long history of this procedure
there is still little knowledge of the long term results. Although the
procedure reduces the incidence of recurrent gleno-humeral instability, both
the incidence of re-dislocations and post-operative arthropathy are relatively
high. Ten years after the procedure the incidence of recurrent instability
ranges from 3.5% to 35%, while the incidence of arthropathy ranges from 39% to
69%. These wide ranges are based on only few studies with relatively small
sample sizes.
Our LORAB-I study aims to evaluate the subjective feeling of instability and
shoulder function *10 year after a Bankart repair. This first part has been
approved by our local ethical committee and data collection will start soon.
The proposed extension of this study (LORAB-II) will focus on the objectively
measured instability and on the development of gleno-humeral arthropathy *10
years after the Bankart procedure. Together, these studies will fill an
important gap in knowledge on the long-term effects of a Bankart repair.

Primary objective
To determine the incidence of recurrent instability (objectively measured using
the Apprehension test, *Relocation test* and the *Release Test*) in our cohort
of patients who underwent a Bankart procedure between January 1999 and end of
December 2005.

Secondary objectives
We will calculate the incidence of athropathy (according to *Samilson and
Prieto*) using radiographs in endo-rotation, exo-rotation and axial view. We
hypothesize that patients, 10 years post-operative, will provide an incidence
of arthropathy between 39% and 69%.
We will calculate the incidence of damage to the glenoid rim (*Bony Bankart
lesion* classified according to Bigliani) and the humeral head (*Hill Sacs
lesions*, classified according to Calandra) and examine whether these lesions
are risk-factors of post-operative (objective or subjective) instability.
We will estimate the predictive value of the subjective feeling (patient
reported yes/no) of instability against the *Apprehension test* (objectified by
physical examination during follow up). We expect that the subjective feeling
of instability can be confirmed with a positive *Apprehension test*.

Further we will examine whether the *Constant score*, OSIS and the WOSI score
are related to the level of arthropathy. Based on a previous study we
hypothesize that these will not be significantly correlated.

This is a cross sectional study based on retrospective data collection.

The benefits will primarily be to society, as we will learn more about the
results of the Bankart procedure in the treatment of anterior shoulder
instability. This group of patients who have undergone the Bankart procedure
*10 years ago is the only population that can provide the answers to our
research questions on long-term effects. No other group would provide us with
this information.
The burden and risk associated with returning to the OLVG for physical
examination can be considered low. The follow-up activities are consisting of
three low impact tests (The *Apprehension test*, the *Relocation test* and the
*Release test*) together with the completion of the *Constant score*.

The risk associated with the making of three radiographs is an exposure of
radiation of approximately 30 uSV. This amount of radiation is equivalent to 3
days of background radiation an average person receives during a normal day (10
uSV) and is therefore regarded a negligible risk.
The follow-up activities will be completed in one hour, including the
radiographs.