Introduction: Degenerative disorder involving the acromioclavicular
joint (ACJ) is quite common especially in the elderly.
One of the surgical modalities of treatment of this disorder is the
Mumford Procedure. Arthroscopic approach is preferred due to
its reduced morbidity and faster post-operative recovery. One
method utilizes the anteromedial and Neviaser portals, which
allow direct and better visualization of the ACJ from the
subacromial space. However, the dangers that may arise from
incision and insertion of instruments through these portals are
not fully understood. This cadaveric study was carried out to
investigate the dangers that can arise from utilization of these
portals and which structures are at risk during this procedure.
Methods: Arthroscopic Mumford procedures were performed
on 5 cadaver shoulders by a single surgeon utilizing the
anteromedial and Neviaser portals. After marking each portals
with methylene blue, dissection of nearby structures were
carried out immediately after each procedure was completed.
Important structures (subclavian artery as well as brachial plexus
and its branches) were identified and the nearest measurements
were made from each portal edges to these structures. Results:
The anteromedial portal was noted to be closest to the
suprascapular nerve (SSN) at 2.91 cm, while the Neviaser portal
was noted to be closest also to the SSN at 1.60 cm. The
suprascapular nerve was the structure most at risk during the
Mumford procedure. The anteromedial portal was noted to be
the most risky portal to utilize compared to the Neviaser portal.
Conclusion: Extra precaution needs to be given to the
anteromedial portal while performing an arthroscopic distal
clavicle resection in view of the risk of injuring the
suprascapular nerve of the affected limb.