Congenital pseudoarthrosis of clavicle is a rare anomaly and was first described by Fitzwilliams in 1910.
Congenital pseudoarthrosis of clavicle results in congenital failure of formation [ossification] of the central portion of the clavicle that manifests as painless lump in the clavicle.
Functional impairment is uncommon in children.
The pseudoarthrosis is fully present at birth.
Familial incidence is reported in some patients, particularly in bilateral cases.
The right clavicle has been affected in almost all the reported cases.
Etiology of Pseudoarthrosis of Clavicle
Clavicle connects the sternum to the acromion and provides support for shoulder function. Clavicle is the first bone of the skeleton to become ossified in the fourth week of gestation, and fusion of the two ossification centers occurs around the seventh week.
Dirsuption of membranous ossification due to environmental insult or anatomic or mechanical event is the main reason behind development of congenital pseudoarthrosis of clavicle.
Cause is not known though abnormalities in aortic arch angiogenesis have been postulated. The incidence of associated cervical ribs is 15%.
Excessive pressure exerted by pulsation of the subclavian artery during the process of development of the clavicle, abnormal intrauterine position and genetic causes have been suggested as possible causes.
It must be noted that the defect is not due to non union of a birth fracture of normal bone as all neonatal clavicular fractures unite rapidly with massive callus.
Presentation of Congenital Pseudoarthrosis Of Clavicle
A nontender swelling just lateral to the middle of the clavicle is discovered at birth or soon afterward. There is no history of birth injury or other trauma.
At the site of pseudoarthrosis, the adjacent ends of the clavicular fragments are enlarged, and there is a variable degree of painless mobility between them. The larger sternal fragment is tilted upward and lies in front of and sightly above the medial end of the smaller acromial portion.
The deformity tends to become more obvious with the child’s growth. Pseudoarthrosis may become painful with some activities that involve movements above head level or with direct compression of the focus.
The deformity usually increases and becomes unsightly with further growth, more so when there is marked mobility at the site of the pseudarthrosis. The overlying skin becomes thin and atrophic. Cosmetically the deformity may be a source of embarrassment to the child.
There is some drooping of the affected shoulder with asymmetry and prominence of the vertical border of the scapula. Mild pain around the shoulder girdle and upper arm may be present.
There is little or no functional disability. A few children complain of weakness of the arm and limitation of shoulder abduction.
Imaging
The radiographic findings are characteristic and include clear separation in the middle portion, with the medial fragment positioned above the lateral fragment because of the action of muscle forces and the postural traction exerted by the weight of the upper limb.
Because of the weight of the upper limb, the lateral segment of the clavicle is tilted inferiorly, and the shoulder droops, is rotated forward, and is nearer to the midline than the opposite normal side.
In congenital pseudoarthrosis of the clavicle there are no other skeletal abnormalities present, a feature that distinguishes it from cleidocranial dysostosis.
MRI is rarely indicated but may be used to determine the extent of the fibrous union, the location of the great vessels, and the space available within the thoracic outlet.
Treatment of Congenital Pseudoarthrosis Of Clavicle
No conservative treatment achieves the union and not all the cases require surgical treatment. Indications for operative treatment are progressive pain, unpleasant deformity, functional limitation and late-starting thoracic outlet syndrome.
Treatment consists of excision of the pseudoarthrosis mass, curettage of the bone ends, internal fixation with a threaded Steinmann pin or semitubular plate and grafting with cancellous onlay autogenous bone graft from the ilium.
Image Credit: Eorif
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I was born with pseudoarthrosis of the clavicle. I had 2 or 3 surgeries to fix it when I was around 4-6. After the first time I had the surgery, my parents were told that I looked like I fell out of a tree and needed the surgery again, so I went through the surgery a second time. Each time, the used a piece of my hip bones to connect the clavicle. I don’t remember if I had a 3rd surgery or not. I was very young. When I was 13, my clavicle started hurting doing basic things like writing at my school desk. Now I am 24 and have severe pain under my right shoulder blade and experience pain when I lift my arm higher than shoulder-level and if I lift objects heavier than 5 pounds with my right arm (I’m a small person anyway, so I can’t lift much more than 5-10 pounds regardless, but there is only pain in my right clavicle and shoulder area). I was let go from my job when my doctor told me I can’t lift more than 5 pounds. I haven’t found any research done on the aftermath of adults with pseudoarthrosis of the clavicle and was wondering if anyone has similar experiences to me.
Hey I also have pseudoarthrosis of the clavicle, I think. my shoulder is lower on my right side and when I am doing training with weights it feels as though the ligaments in my shoulder are being unnaturally stretched. My trapezius muscle above the affected shoulder seems non-existent. I am able to get my scapula to stick out by putting my arm behind my back and pressing my shoulder inwards towards my sternum. The affected shoulder also hangs closer to my sternum than my left shoulder does. I want to be able to lift weights and improve my strength but I am afraid that my shoulder will wear out more quickly because of this condition. My parents say that when I was a baby and they laid me on the side with the condition, I reeled back in pain. That seems more indicative of a fracture at birth but the article says that the bones fuse together very quickly if it is a fracture. Any help would be appreciated!
Jon,
For all your concerns, you would be better served by a doctor who could see you in person.
Take care.