At the Paley Institute, we have treated the full spectrum of the sequelae of Streeter's Syndrome. We have treated the problems ranging from constriction bands at different levels requiring releases, club feet requiring correction, knee contractures requiring straightening, and leg length discrepancy requiring equalization.
Constriction Band Releases
Constriction bands produce limitation of growth and obstruction of circulation and nerve development. As such, deep constriction bands should be released with great caution to avoid vascular damage. This vascular damage can be both in the form of damaging the venous as well as arterial circulation. Although the nerves may already be damaged beyond repair and regeneration, release of the bands can help the nerves recover if the band release is performed early.
Dr. Paley prefers to perform the band release in the first six months of age when the bands are very deep. Nevertheless, he has successfully released these bands at older ages which is more common since patients often do not present early.
The band releases should be done in two stages when the band is circumferential. This is in order to allow the venous and lymphatic drainage to reconstitute. Therefore, the bands are released 50% of the way (180 degrees) and then three months later for the remainder of the distance (the other 180 degrees). The blood vessels should be mapped out using a Doppler in order to hear them and extra care in the dissection is taken as one approaches the zones where the blood vessels pass longitudinally. At the Paley Institute, we have successfully released constriction bands both improving the neurovascular situation for the residual limb as well as improving the appearance of the limb. Once the constriction band is released, then other effects of the syndrome, such as deformities, contractures, limb length discrepancy, etc. can be addressed.
Correction of Joint Contractures and Deformities
Associated joint contractures such as clubfoot, and knee flexion contracture are very commonly associated with bands in the leg and thigh respectively. After constriction band release as described above, the next stage is to correct these deformities. Because of the high-risk situation with regards to the vascularity of these limbs, it is often better to correct these deformities gradually by means of gradual distraction using external fixation. Dr. Paley therefore applies an external fixator during a second stage surgery, usually performed around age two or older. The deformed foot or knee is gradually corrected until it is in a normal position. Once it achieves that position it is held there for a similar amount of time to what it took to get it straight. The external fixator is then removed and a brace is applied. At the time of removal of the external fixator until the brace is made, a cast is applied as a temporary brace. Once the swelling decreases, the permanent brace can be fabricated. The brace is used for at least six months day and night and then after that nighttime only in order to promote function of the limb. Physical therapy is essential to try and regain the function of the previously contracted joints.
Limb Length Discrepancy
Limb length discrepancy is very common when amniotic bands affect only one side and that side is usually retarded in its growth compared to the opposite normal side. Limb lengthening can be carried out simultaneous with joint contracture correction in some cases since both require an external fixator. Most commonly, the lower leg (tibia and fibula) are the bones lengthened. Gradual distraction between three quarters to one millimeter a day is carried out after cutting the bone and placing an external fixator on to the tibia and foot. Once the desired length is achieved the bone is held in that position until it consolidates and then the external fixator can be removed. The time in the external fixator follows the usual guidelines of approximately one month for every centimeter of lengthening. However, since the circulation is sometimes not as good in amniotic band syndrome, one might expect a slightly longer external fixation treatment time than the average. Lastly, older children with limb length discrepancy from amniotic band syndrome are candidates for implantable limb lengthening using the PRECICE.
Constriction Bands of the Fingers and Syndactyly
Constriction bands affecting the fingers can lead to a variety of deformities as well as shortening of the fingers. They most commonly lead to syndactyly as well. In these cases, Dr. Paley usually addresses the deformity and the syndactyly first including release of the band at the same time. This may require skin grafting by harvesting skin from the groin. This is done at approximately one year of age. At a later date, lengthening of the short fingers can be considered. In most cases, lengthening is not required and the focus is only on function of the fingers.
At the Paley Institute we provide all of the services needed and therefore both the release of the band, straightening of the fingers, separation of the syndactyly, and lengthening are options that can be discussed with the family and planned in to the long-term management.