Introduction to biomechanics


Limb Lengthening and Reconstruction Techniques

Limb Lengthening and Reconstruction
TechniquesChildren and adults can be appropriate
candidates for the procedure. Children with
16th  November  2006congenital deformities such as fibular
hemimelia, congenital short femur and
Author:  Chris  Maylorhemiatrophy will often have unequal leg
length and this may be associated with
Limb lengthening and reconstructiondeformity. Many adults have had this
techniques can be used to replace missingcondition since childhood and have developed
bone and lengthen and/ or straighten deformedback pain and hip arthritis from the leg
bone segments. The procedures may belength discrepancy. Growth plate fractures
performed on both children and adults whoand bone infections in children can cause
have limb length discrepancies due to birthstunting of growth that results in
defects, diseases or injuries. The limbdiscrepancy.
lengthening and deformity correction process
works on the principle of distractionFollowing trauma, bones can heal in a
osteogenesis. This is a revolutionary conceptshortened and deformed position (mal-union).
that reverses the long-held belief that boneSometimes the bone can even remain unhealed
cannot be regenerated. In this process, a(non-union). Limb lengthening procedures
bone that has been cut during surgery can beaddress all of these issues. We have been
gradually distracted (pulled apart), leadingable to successfully correct large
to new bone formation (osteogenesis) at thedeformities and equalize limbs with
site of the lengthening. In this way, bonediscrepancies of several inches. A segment of
segments can be lengthened by 15 to 100bone can be missing after a bone tumor, bone
percent of their original length. We use ainfection or severe fracture. We can
variety of techniques, including the use oftransport  new  bone  to fill in this defect.
monolateral (one-sided) and circular external
fixation devices, to correct angularShort stature can be very disabling in
deformities as well as limb lengthpatients with dwarfism, for example. We can
discrepancies. With these procedures, welengthen both legs simultaneously to increase
provide opportunities for individuals whostature. We have been able to lengthen
previously  had  no  treatment  alternatives.achondroplastic dwarf patients 12 inches in
the legs and five inches in the arms. This
The regenerated bone is normal and does notallows them to function more independently
wear out. The muscles, nerves and bloodand be able to reach the telephone, toilet
vessels grow in response to the slow stretchand  gas  pedal,  for  example.
like they do during a growth spurt or in
pregnancy. The actual procedure is minimallyYoung adult patients with leg deformities are
invasive and requires only one or two nightsat risk for developing arthritis as a result
in the hospital. Patients aren't in much painof their malalignment. These same techniques
since the distraction is so gradual andcan be used to correct severe deformities
patients can continue to walk during thesafely and avert the need for joint
treatment.replacement.



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