Background: The clavicle provides the structural bar of support for the shoulder to keep it at a good distance from the sternum. As a result it allows the arm to have a good range of motion along with a variety of other musculotendinous attachments. When it comes to shoulder narrowing surgery shortening of the length of the clavicle easily brings int the width of the shoulders since its established support is lessened. But when it comes to shoulder widening or clavicle lengthening surgery it is biomechanically a different story.
Expanding or stretching out the length of the clavicle involves pushing out on all of the established tissues which have developed around that length. This means the entire shoulder or pectoral girdle mms be stretched. While this is surgically done for the clavicle part of the girdle, what about the scapula? Its surrounding muscles, particularly the trapezius and rhomboid, form tight attachments that provide stability to the outer shoulders. Pushing against them by lengthening the clavicle does not provide the same change of length effect as shortening the clavicle does.
An interesting question in clavicle lengthening (shoulder widening) is whether enhanced shoulder musculature makes the procedure prohibitive?
Case Study: This very muscular male desired to have his shoulders widened to look more proportionate with his enhanced soft tissues. In essence to have a better shoulder framework onto which the larger muscles would sit. His clavicles were less than 16cms in length and were very s-shaped. In preparation for the surgery he stopped lifting weights for four months prior and replaced it with shoulder stretching exercises. The preoperative markings included 4 cm long incisions in the supraclavicular fossa.
Under general anesthesia and in the extended supine position (blanket roll centrally placed done the spine, bilateral sagittal split osteotomies were marked and performed through the supraclavicular incisions. Upon splitting of the segments note that no lateral movement occurs in the outer clavicle segment.
The outer segment of clavicle was then slide out forcibly to a 15mm gap and held into position with a single 3.5mm lag screw. A 10 hole 3.5mm thick s-shaped clavicle plate was then applied with three screws on each outer and inner segment of the bone. Allogeneic bone putty was applied to the four half cortical bones defects.
A key technical point is that the very medial incisions along the inner third of the clavicle do not permit screw fixation to be placed through it in the outer screw holes of the plate. They are placed by a percutaneous technique using a drill guide to protect the skin.
The supraclavicular skin incisions are closed with a subcuticular technique, a remarkably small incision for placing a rigid fixation plate that is essentially as long as the clavicle.
His 4 day postoperative evaluation shows the improvement obtained with x-rays confirming the plate fixation of the clavicle lengthening obtained.
Clavicle lengthening by the linear changes obtainable is a less effective procedure than clavicle reduction. That is simply a function of reducing established support vs forced expansion of the tight shoulder girdle tissues. The more muscle one has it is logical to assume that this soft tissue mass is going to make it more difficult to extend the clavicle length…an already tough assignment. I asked this patient if he was to undergo the surgery that it would be in his best interest to stop building muscle and start an aggressive shoulder stretching regimen.
Case Highlights:
1) Clavicle lengthening poses challenges as stretching out the structural support of the shoulder meets the resistance of the tight soft tissues of the pectoral girdle.
2) In the very muscular body builder male a cessation of weight lifting substituted with stretching is needed before surgery.
3) Very rigid plate fixation with only lengthening the sagittally split bone ends to the point of maintaining good axial alignment (usually in the 15mm range) is the best way to lower the risk of postoperative complications
Dr. Barry Eppley
World Renowned Plastic Surgeon