Treating a limb deformity takes special skills that reflect not only technical capabilities, but also an appreciation of the mechanical forces involved as well as an ability to meticulously plan the necessary procedure to correctly restore normal anatomy as closely as possible. If you are unfortunate enough to have suffered from a limb deformity, you would want to have an experienced senior surgeon with special interests in deformity managing your condition, familiar with the best available techniques to correct that deformity safely and reliably. Deformity correction generally involves a process of elimination, first identifying the various treatment options available, before making a carefully considered decision that best matches the nature of the pathology, the expectations of the patient, and the individual surgeon’s skill set. Commanding equal parts carpentry, science, art, and medicine, surgery for deformity correction often requires a special flair for creativity that complements the knowledge gained during formal education and training, and not all surgeons possess the necessary attributes.
That said, deformity is one of the most basic considerations in orthopaedic surgery, and is fundamentally important to every discipline within the field. This includes paediatric conditions, trauma, spine, foot and ankle, hand, upper limb, sports medicine, and adult reconstruction. Abnormalities of lower extremity alignment are often the result of trauma, may be of congenital origin, or can be developmental in nature, and range from mild to severe. Critical aspects to consider when assessing deformity include elements of angulation, rotation or torsion, translation or displacement, and leg length discrepancy, either alone or in combination. Many methods have been described for the evaluation of deformity and to plan corrective osteotomies. Some of these techniques were specifically designed to be used for proximal tibial or distal femoral osteotomies stabilised with plates and screws, while others were described principally for use with intramedullary nails or external fixation. Strategies to assess and preoperatively plan for deformity correction are in fact governed by the principles of geometry, and should be considered completely independent of the osteotomy technique or chosen method of stabilization.
Deformity is broadly defined as any deviation from normal anatomy, and its formal analysis must consider both malalignment and joint orientation. Coronal plane alignment of the lower extremities is the most essential consideration, as it is linked to degenerative arthritis resulting from excessive biomechanical loads. Joint malalignment is considered a strong predictor of the development and progression of osteoarthritis. As little as 5 degrees of varus in a statically loaded skeleton can increase the compressive loads in the medial compartment of the knee from 70% to 90%, and even apparently minor deformities may have significant long-term consequences. If you do live with a visible deformity, it is therefore important to have this critically evaluated by a surgeon with special knowledge and experience in this demanding sub-specialty of orthopaedic surgery. Studies have demonstrated that varus malalignment of only a few degrees over many years definitely increases the incidence of degenerative changes in the knee, while in patients with a leg length inequality of more than 2 cm the incidence of osteoarthritis is doubled.
Abnormalities of alignment and joint orientation can be corrected most accurately by applying the fundamental principles of deformity correction. Jackson first suggested the use of osteotomies for the correction of varus or valgus lower extremity deformities as early as 1958, to alter the mechanics and unload the affected compartment of the knee. Coventry later championed these concepts, and advocated using re-alignment osteotomies to alleviate knee pain by decreasing thrust with weight bearing, while simultaneously transferring loads to the normal or less affected compartment. Several recent studies have now confirmed the long-term benefits provided by re-alignment osteotomies when used for deformity correction of the lower extremity.
Needless to say, these procedures should always be undertaken in a very systematic and ordered fashion, and they are almost certainly done best by surgeons very experienced in this particular area of orthopaedic sub-specialization. Unlike other centres, deformity correction surgery at the Limb Reconstruction Centre at MQ Health is considered a vitally important component of our practice, not just an occasional exercise we suggest when a patient is unsuitable for joint replacement surgery. The specialist surgeons of the Limb Reconstruction Centre have tremendous experience in this complex, difficult, and demanding area. Few, if any, other centres in Australia have such an experienced and knowledgeable group of orthopaedic surgeons, and we would be pleased to consult with you, analyse the deformity, and advise you as to how to most effectively and safely correct the deformity as best as possible, within the limits of what is technically possible using the most advanced techniques and devices available in medicine and surgery today.
