Management of Forearm Bone Gap Non-Unions by Ilizarov Technique

Different factors like fracture location and complexity, patient characteristics and surgical intervention are involved in the development of forearm bone non union [1,2]. Radius and ulna non-unions are usually associated with complex injury, inadequate initial reduction, unstable fixation. Anatomical and functional relationships between radius and ulna are so peculiar that it represents a sophisticated functional unit. That’s why fractures of the radius and ulna should be considered like articular fractures [3].


Introduction
Different factors like fracture location and complexity, patient characteristics and surgical intervention are involved in the development of forearm bone non union [1,2]. Radius and ulna non-unions are usually associated with complex injury, inadequate initial reduction, unstable fixation. Anatomical and functional relationships between radius and ulna are so peculiar that it represents a sophisticated functional unit. That's why fractures of the radius and ulna should be considered like articular fractures [3].
The function of the forearm is to assist the hand in space positioning and to support the hand movements. Pronation and supination of the forearm occurs at the radio humeral, proximal radio ulnar, and distal radio ulnar joints. Failure of the relationship between radius and ulna due to changes in the length impairs the forearm function and the ability to position the hand in space. When non-union occurs in the forearm bones it impairs forearm, elbow and wrist motion. In these cases fracture healing is a necessary condition to recover a physiological function the upper limb.
Based on the characteristic of the bone ends, aseptic nonunion can be distinguished into atrophic and hypertrophic [4]. Adequate treatment of forearm bone non-union must be considered providing with biological stimulation and elastic mechanical stability by Ilizarov technique. Ilizarov fixator has osteogenesis, osteo conduction, osteo induction, mechanical properties and vascularity [5].
Autologous bone graft is the transplantation of bone of the same individual from an anatomical donor site to one receiver. Compared to auto graft, allograft are easier to use, require less surgical time and are potentially unlimited in amount, although allograft presents disadvantages such as higher risk of infection, viral disease transmission and the need of a bone bank available to the hospital [6,7].
The aim of this study was to show the treatment of gap nonunions of forearm bones by Ilizarov technique through distraction osteogenesis without bone grafting. We retrospectively reviewed 26 patients determining the use of Ilizarov in terms of A. Rate of healing of non-unions without grafting.

B.
Time of healing and C.
Functional results

Materials and Methods
From 2000 to 2015 a total of 26 patients have non unions of forearm bones with Ilizarov compression-distraction device. We consider a non-union "Arrest of bony fractures repair process with the formation of fibrous or cartilaginous tissue in between the main fragments and fracture has remain un-united for 6-9 months due to mechanical or biological failure judged by clinical and radiological evidence".

Exclusion criteria were
a.
Presence of other fractures in the same limb at the time of the primary forearm injury and b.
The initial treatment of the fracture which evolved into nonunion consisted of open reduction and internal fixation with plate and screws, intramedullary rods, external fixation or cast immobilization (Table 1). Non-union evolved in radius done in 5 patients, in ulna 6 patients, and non-union of radius and ulna evolved in 15 patients ( Table 2).

Results
No per-operative complications occurred. There was no early or late infection. All the non-unions healed. Average time of healing of non-union was 7 months, ranging from 5-12 months (Figures 1-4). Patients resumed ADLs (activity of daily living) 12 days after surgery with Ilizarov apparatus (Figures 5-8).

Discussion and Conclusion
Non-union of forearm bones are difficult to treatment. Ilizarov fixation technique in forearm bone non-union have been shown to be secure to achieve new regenerate bone in the big gap union of radius and ulna by distraction osteogenesis. In atrophic non-union our goal must be the restoration of a good biological environment. Han et al. [8], and Jupiter [9] reported higher success rates using vascularised bone graft which requires longer surgical time and specialized equipment. But Ilizarov compression-distraction technique [10] requires a demanding post-operative care. Higher success rate was achieved in forearm alignment and function with Ilizarov technique. 5 cm and more gaps with atrophic non-union of forearm bones are difficult to treatment without Ilizarov technique. We found the excellent rate of gap healing and no rate of infection in our series due to distraction osteogenesis.