SUMMARY
Nonunion of the humerus continues to challenge orthopaedic surgeons. Because it is usually very difficult to obtain union and coexisting problems of deformity, infection and limb length discrepancy are often not primarily addressed. In more complex cases with atrophic bone ends, substance defects, chronic osteomyelitis or a combination of these, amputation may be the eventual outcome despite current techniques of internal fixation, bone grafting and electrical stimulation
The Ilizarov method is currently being used to lengthen limbs, correct deformities, fill in gaps and treat non-infected and infected nonunins. The fundamental concepts of this methos is distraction osteogenesis at corticotomy. A corticotomy is created by osteotomizing the cortex, usually in the metaphyseal region of a long bone. This is done subperiosteally and the cutting of cortex is done in a way that avoids cutting the medullary contents. It is performed with a sharp osteotome and care must be taken not to injure the medullary circulation of nutrient vessels. The cortex is osteotomized in the humerus. The medial cortex fracture is completed by a twisting manual osteoclasis maneuver,
The Ilizarov method offers several advantages over other conventional methods of management of nonunion. However, several problems, obstacles and complications may occur if this technique is not properly applied.
This article is based on thorough review of literature in the subject of the Ilizarov method and its use in the management of humeral nonunion, as well as analysis of our own results and discussing them in comparison with other results reported in the literature.
In our series, we treated 20 patients with nonunited humeral fractures; 16 cases were infected, 14 cases have associated deformity, 3 patients had preoperative shortening with a range of 1-2 cm and 3 patients had bone gap with a range of 1-2 cm. failed previous operations ranged from 1 to 3 times and the mean duration of nonunion was 12.65 ± 3.91 months. We used monofocal treatment with all patients. The mean duration of treatment was 8.1 ± 2.34 months.
Union was obtained in all 20 patients (100%). Persistent infection occurred in 4 patients (20%) and residual deformity more than 7° occurred in 5 patients (25%). Residual shortening occurred in 7 patients. Thus the bone result was excellent in 13 cases, good in 4 cases, fair in 3 cases and no poor results occured.
Eighteen patients (90%) were active postoperatively and the functional result was excellent in 12 cases, good in 4 cases, fair in 2 cases and poor in 2 patients. It should be noted that an excellent bone result does not necessarily mean that the functional result will be excellent also.
The most common complication was superficial pin track infection but no ring sequestrum occurred. Honey had been used successfully as a local measure in managing such infection.
The technique needs several prerequisites to obtain optimum results and minimize risks of complications. These include proper patient selection, experienced surgeon, proper preoperative assessment, regular careful follow up and the integral role of physiotherapy. The surgeon who will take on the challenge of this time consuming technique should know that the patient should be patient and the surgeon should be patient, as well as knowledgeable and skilled in the treatment of fractures with external fixators.
As with any complex system, the Ilizarov method has a long learning curve. Progression along this learning curve represents a better understanding of the cardinal principles of the method, the mechanical possibilities and the potential applications of the technique. Proper tactics and techniques of apparatus assembly and application will improve the rate of union and shorten the duration of treatment , as well as enhance patient tolerance of the apparatus.
As we gain experience with the method, we find ourselves capable of solving increasingly more difficult problems with a level of success rarely, if ever, achieved with more conventional methods.
The process by which we decide on the best treatment is a complex one. There are many factors that must be considered. In the course of our evaluation of each specific case, some of the factors will assume primary importance, while others may be relegated to secondary considerations, in making treatment decisions there is no "cookbook" method that can be followed. Conversely, the cardinal principles of stability, axial alignment, vascularity and function must always be considered. If these four principles are addressed, nature will take care of the rest.
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