Influence of radiograph type and patient positioning on shortening of displaced midshaft clavicle fractures.

Fractures of the clavicle are common, comprising up to 5% of all skeletal
lesions in adults [1]. Most clavicle fractures are localized at the level of
the midshaft-diaphyseal third [2]. Dislocation of the fracture elements in
midshaft clavicle fractures (MSCF) occurs due to the actions of the
sternocleiodomastoid muscle, which displaces the medial fragment superiorly and
posteriorly, and of the deltoid and great pectoral muscles, which shift the
lateral fragment inferiorly and anteriorly. These shifts cause a malaligned
fracture that may result in symptomatic shortening of the clavicle [3].
In the last decade, many studies have reported that a shortened clavicle can
lead to pain, loss of strength, rapid fatigue, hyperesthesia of the hand and
arm, difficulty sleeping on the affected side and aesthetic complications [4].
Mean post-traumatic shortening of the fractured clavicle is approximately 1.2
cm, but a shortening of up to 3 cm has been reported [5]. Many authors have
observed the degree of symptomatology and occurrence of malunion and
pseudoarthrosis after MSCF is related to the extent of shortening and
displacement of the bone segment [6]. It has been described that there are
poorer outcomes when relative shortening of the clavicle is more than 9.7% as
compared to the original length.[Giorgi BMC research notes]
In summary, shortening and displacement of MSCF have been found to be
predictors of poor outcome concerning non-unions, persistent posttraumatic
symptoms and cosmetics in conservatively treated MSCF. Therefore lately the
tendency has been to surgically reduce and fixate MSCF if absolute shortened >
1,5/2cm or displaced more than the diameter of the clavicle*s shaft. A survey
among upper extremity surgeons showed that 60% state that shortening is the
most important factor in the decision for surgical versus nonsurgical
treatment. [7]
However there is no standardized protocol on how to evaluate this shortening in
a fractured clavicle in regards to patient positioning and X-ray views. AP,
cranio-caudal and caudo-cranial views in anatomical (standing) and supine
position are used in current practice. These different views will project
differently due to the diverging angle of the X ray beams, the sigmoid shape of
the clavicle and the mass of the arm pulling on the lateral fragment of the
fractured clavicle. This will result in different measurements and various
degrees of shortening and displacement and thus differences in indication for
surgery.
Since shortening becomes a more important factor in deciding whether surgical
intervention is indicated, the aim of this study is to investigate if the type
of X-ray and patient positioning is influential on the measured shortening in
the acutely fractured clavicle.

It is hypothesized that the type of radiographs and patient positioning is
influential on the measured relative and absolute shortening of the MSCF. The
goal of this study is to investigate to what extent the type radiograph used
and patient positioning is influential on the measured shortening.
interobserver and intraobserver reliability will be calculated.

A prospective multi-center case series is conducted in the Radboud UMC Nijmegen
OLVG Amsterdam, CWZ Nijmegen, Rijnstate Arnhem and the Admiraal De Ruyter
hospital in Goes. Participating departments will be the ER, General Surgery,
Orthopaedic Surgery and Radiology

Each patient will undergo 7 additional X-ray*s. Normally an AP and one other
direction is made In this study the diagnosing AP will be fabricated as well
as 8 additional which is 7 more than in standard practice. The additional dose
of milliSieverts ( about 0.007 mSv) constitutes negligible additional lifetime
risk of fatal cancer. [10]
(http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty_xray) Excacerbation
of pain during protracted and retracted positions of the arm can be expected.
By administering sufficient analgetics this adverse effect for the patient will
be relieved.


Adverse Events

There is no reason to expect any serious adverse events. In case of a serious
adverse event this will be reported to the VCMO by the researchers and the
study will be stopped. Monitoring will be ensured by PH and AG.


Ethical Issues

Research protocol will be reviewed by the hospital*s medical ethical board
(VCMO). The value of this study and possible impact on indication for surgical
intervention in MSCF in relation to the additional impact on the subject is
acceptable according to the researchers. This study will be executed according
to the principles of the declaration of Helsinki and according to the WMO.