Orthopedics - Oleksa A.P. 2006

Congenital upper limb malformations
Congenital forearm malformations
Amniotic bands and congenital amputations

Amniotic bands are relatively rare, occurring in approximately one out of every 2,000 to 2,500 newborns (Blackfield H.M., 1955). In clinical practice, they can manifest in any part of the upper or lower extremities. These bands may be either superficial or deep. However, as the child grows, a superficial band can cause the same complications as a deep one, because the dense fibrous tissue of the band lacks the growth potential of normal tissue, thereby constricting the limb segment progressively tighter. The amniotic band encircles the segment and typically appears as a narrow, circular groove of varying depth with a firm, fixed base. Multiple bands are sometimes observed on the fingers and may be associated with other Congenital hand malformations (such as Syndactyly).

Initially, a superficial band presents primarily as a cosmetic defect. The deeper and denser the amniotic band, the more pronounced the local circulatory and lymphatic disturbances distal to it become. As previously mentioned, with the child's growth, the constriction of the limb segment progresses, tissue edema increases, and sensation distal to the band deteriorates, ultimately impairing limb function. Moreover, circulatory compromise can be severe enough to cause tissue necrosis and amputation.

Congenital amputations result from amniotic bands and the intrauterine detachment of a limb segment at an early stage. Chaussier describes a case where a newborn infant was delivered with its amputated arm already detached.

Treatment. We disagree with Blackfield and Hause that superficial bands require no special treatment. As noted, superficial bands do not expand as the child grows because they are based on scar tissue, and they can cause the same complications as deep ones; therefore, we believe that all types of amniotic bands necessitate surgical intervention.

The only question is when to perform surgery. We believe that children with superficial bands can be operated on during their second or third year of life, depending on the rate at which limb segment constriction progresses. Deep bands require Surgical treatment during the child's first year of life, or even at 3 to 4 months of age, particularly in the presence of tissue edema and impaired Blood AND Lymph Circulation.

Surgery is performed under general anesthesia using a tourniquet. Tissues must be incised in a zig-zag (stepped) pattern, as linear circular incisions can cause recurrent constriction upon healing. It is crucial to radically excise the fibrous scar tissue of the band within healthy tissue boundaries without damaging Blood Vessels. Due to this inherent risk, several orthopedists (Stevenson, Blackfield, Hause, et al.) recommend treating children with deep bands in two to three staged Procedures. Simultaneously with the excision of scar tissue, tenolysis, tendon lengthening, or neurolysis are performed when necessary. It is essential to close the wound without tension to achieve primary healing. However, because Skin deficits are very common following scar excision, autologous skin grafting is often required.

Congenital amputation can occur at any level of a limb segment, though it is most frequently observed at the level of the crus (leg) and forearm. Congenital stumps may also be bilateral, involving either identical or different segments.

As a rule, the lengths of lower extremity stumps are suitable for prosthetic fitting. If a rudimentary protrusion is present on the stump, reconstructive surgery may occasionally be required, followed by prosthetic fitting around 2 to 3 years of age. Children adapt remarkably well to prostheses; they walk, run, play soccer, and are virtually indistinguishable from their healthy peers.

A congenital upper extremity stump significantly impairs a child's physical capabilities, and bilateral stumps make even basic self-care difficult. Every effort is made to assist such children. In cases of finger defects—particularly involving the first, second, and third digits—procedures such as phalangization, toe-to-hand microvascular toe transfer, and reconstructive surgeries to improve grip are performed. Occasionally, patients with bilateral congenital forearm amputations utilize simple or advanced assistive devices to perform physical tasks.

Today, patients with bilateral upper extremity amputations can be provided with bioelectric prostheses manufactured at the Kharkiv Research Institute of Prosthetics and Prosthetic Design (NIIP and PB). These advanced bioelectric prostheses enable patients not only to flex and extend their fingers, but also to perform forearm supination and pronation.