Anterior Approach to the Clavicle
The anterior approach to the clavicle provides exposure of the entire bone
allowing:
1. Open reduction and internal fixation of fractures
2. Reconstruction of the sternoclavicular and the acromioclavicular joints
in case of dislocation or subluxation
3. Drainage of sepsis
4. Biopsy and excision of tumors
5. Osteotomy for malunion
The brachial plexus and subacromial vessels can also be approached
via this surgical approach. To do this an osteotomy of the clavicle is
required).
Bleeding from subcutaneous vessels and vessels in the platysma
muscle is very common. Because of the proximity of great vessels, such
superficial bleeding must be controlled to ensure adequate visualization of
the structures (see Fig. 1-1).
Position of the Patient
Place the patient supine on the operating table. Break the table and elevate
the head end, so as to elevate the shoulder area. Place a sandbag between
the medial border of the scapula and the spine. This will allow the shoulder
to drop back and often this maneuver reduces fractures of the middle third.
Landmarks and Incision
The sternal notch is the most medial landmark of the incision. From the
sternal notch, palpate the clavicle laterally to the acromioclavicular joint,
palpating its subcutaneous surface.
Make an incision following the S-shaped clavicular anatomy,
beginning from the medial end. The site and length of the incision depend
on the clinical indication for surgery (Fig. 1-1).
Internervous Plane
Because the approach is directly onto the subcutaneous surface of the
clavicle, there is no internervous plane. However, the incision cuts across
numerous small subcutaneous nerves, branches of the supraclavicular
nerve which cross the operating field from superior to inferior running in
the substance of the platysma muscle.
Figure 1-1 The subclavian vessels are very close to the clavicle.
Figure 1-2 A: Make a longitudinal incision overlying the subcutaneous surface of the clavicle. The site and length of the incision are determined by the pathology to be treated and the implant to be used. B: Deepen the incision in the line of the skin incision to expose the platysma muscle. Note the presence of several cutaneous nerves.
Superficial Surgical Dissection
Deepen the skin incision through the platysma to reach the subcutaneous surface of the clavicle. Take care to diathermy the numerous vessels present within this muscle (Fig. 1-2). Try to preserve as many branches of the supraclavicular nerve as possible. Safe zones exist within 2.5 cm of the sternoclavicular joint and within 2 cm of the acromioclavicular joint where no branches of the supraclavicular nerve are present. The nerve usually divides into a medial and a lateral branch2 both of which cross the operative field if the incision is used for fixation of a fracture of the middle third of the clavicle. Division of a single branch may not produce any postoperative numbness due to overlap in the cutaneous distribution of the branches of the nerve.
Deep Surgical Dissection
Gently strip soft tissues off the subcutaneous surface of the clavicle in an
epiperiosteal plane. Take care to preserve as much soft tissue attachments
as possible, particularly in cases of fracture fixation.
Dangers
Nerves
The brachial plexus with the subclavian artery has a variable relationship
with the clavicle. These structures lie posterior to the bone medially and
then lie immediately inferior to the clavicle in the middle and lateral thirds
(Fig. 1-3). To ensure that the plexus is uninjured, remain on the
subcutaneous surface of the clavicle. If dissection is required inferior to the
bone, develop a plane between the periosteum of the clavicle and the
subclavius muscle. Also, be aware when drilling for fixation of fractures
that penetration of the bone should be minimized in its posterior surface
because of the close proximity of the nerves and vessels.3
Branches of the supraclavicular nerves cross the operative field from
superior to anterior. There is wide variation in the position of these nerves
which should be preserved if possible.
Vessels
The subclavian artery and vein lie immediately inferior to the clavicle in
its middle and lateral thirds. Avoid dissection inferior to the clavicle, if
possible. Dissection onto the subcutaneous surface and the anterior surface
is safe.
How to Enlarge the Approach
The exposure can be enlarged longitudinally along the whole length of the clavicle as required (see Extensile Measures in this chapter). The approach can be extended distally into the anterolateral approach to the proximal humerus and midshaft of the humerus using the deltopectoral interval (see Fig. 1-20).
Figure 1-3 Deepen the incision through the platysma muscle in the line of the skin incision to expose the subcutaneous surface of the clavicle.
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