Novel assessment of the sternoclavicular joint with computed tomography for planning interventional approach.

OBJECTIVES

To describe the plane of the sternoclavicular joint (SCJ) to aid planning of instrument orientation during invasive procedures.

METHODS

Computed tomography (CT) images of 80 consecutive patients aged 25 to 40 years with appropriate chest imaging series were retrospectively reviewed. Patients with a previous median sternotomy, fused manubriosternal joint or fracture were excluded. The medial clavicle was found to vary greatly in its anatomy such that a representative morphology could not be described. The manubrium was found to be a more consistent structure and was examined in more detail. The angulation of the SCJ was measured in three orthogonal planes using CT multiplanar reformats. Each SCJ (160 in total) was assessed for transverse, coronal, and sagittal angulation of the central manubrial articular surface in respect to the long axis of the manubrial body using a newly devised measurement technique.

RESULTS

The mean angles (± standard deviation) of the SCJs were 62.4 ± 9.7° to the transverse plane, 149.3 ± 7.3° to the coronal plane and 69.8 ± 7.5 to the sagittal plane. There was no significant difference in transverse (p = 0.41) or sagittal (p = 0.60) angulation between sides, however there was a significant difference for the coronal plane (p = 0.04). No significant differences were noted between the sexes in any plane.

CONCLUSIONS

Increasing use of invasive diagnostic and treatment techniques dictate that a safe approach to the joint should be used to reduce the risk of iatrogenic injury. This study adds to existing knowledge of SCJ anatomy and its variation within the population. Understanding this can minimize the risk to adjacent structures when approaching the SCJ with injection needles or arthroscopic instruments.