الفهرس 
Proximal RadiusOnly 14 pages are availabe for public view
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Abstract
Because children tend to protect themselves with their outstretched arms when they fall, upper-extremity fractures account for 65% to 75% of all fractures in children. The distal humerus accounts for approximately 86% of fractures about the elbow region. Supracondylar fractures are the most frequent elbow injuries in children, reported to occur in 55% to 75% of patients with elbow fractures. Lateral condylar fractures are the second most common, followed by medial epicondylar fractures. Elbow injuries are much more common in children and adolescents than in adults. The peak age for fractures of the distal humerus is between 5 and 10 years old. (James et al., 2006).
Angular deformities of the distal humerus after supracondylar fractures are much less common since the development of modern techniques of skeletal stabilization. In the past, the incidence of cubitus varus deformity after supracondylar fractures ranged from 9% to 58%. Pirone et al. (1988) reported cubitus varus deformities in 14% of patients treated with cast immobilization compared with 3% in patients with percutaneous pin fixation. A decrease in frequency of cubitus varus deformity after the use of percutaneous pin fixation has been reflected in other recent series.
Cubitus varus is the deformity in which the long axis of the forearm is deviated inward in relation to the long axis of the arm (the reserve of the carrying angle). It is a complex three dimensional deformity which consists of varus, hyperextension and internal rotation deformity of the distal bone fragment of the humerus (Yamamoto et al., 1985).
The pathogenesis of cubitus varus deformity after supracondylar fracture of the humerus in children had been discussed by many authors with great contradiction. Two main causes were discussed: Growth disturbance and Malunion.
There is general agreement that cubitus varus is due to malreduction rather than growth arrest. However, Bipin et al. (2005) reported a case of cubitus varus following a supracondylar fracture in a child with magnetic resonance imaging (MRI)-proven growth arrest. There has been no published report in the literature of cubitus varus in a supracondylar fracture secondary to bony bar formation in the physis.
The case illustrates that supracondylar fractures can cause physeal injury, leading to asymmetric growth arrest of the distal humerus. The cubitus varus in such cases is progressive. Magnetic resonance scanning is a useful investigation in the diagnosis of physeal bars. Corrective osteotomy in such cases should be delayed until skeletal maturity to prevent recurrence of the deformity.
As for the treatment of any post-traumatic malalignment, options include:
Observation with expected remodeling:
Hyperextension deformity may remodel over time, but correction is slow and inconsistent. In one series, hyperextension deformities remodeled as much as 30 degrees in very young children, but in older children, there was no significant remodeling in the flexion hyperextension plane. If hyperextension appears to be a major problem, osteotomy should also be directed at this deformity rather than simple correction of the varus deformity; this situation requires a multiplane osteotomy (James et al., 2006).
Hemiepiphysiodesis and growth alteration:
Voss et al. 1994 showed four patients had growth arrest and avascular necrosis; lateral epiphysiodesis was performed to prevent recurrent deformity in two of these patients.
Corrective osteotomy :
Many operations have been described for correction of cubitus varus. These are broadly divided into three groups: medial opening wedge, lateral closing wedge, and oblique or dome or step-cut or reverse v or pentalateral or three dimensional or arc or transverse or Lateral invaginating Peg osteotomy.
Functional outcomes are generally good, but the preoperative functional deficit is nearly always minor in patients with cubitus varus deformities. However there were some reported complications appeared with cubitus varus such as ulnar neuritis or palsy, Tardy Posterolateral Rotatory Instability of the Elbow, Failure of active extension, posterior instability of the shoulder, posterior interosseous neuritis, radial nerve entrapment in the callus, recurrent posterior dislocation of the head of the radius and second fractures.
Complications of humeral osteotomy include stiffness, nerve injury, and persistent deformity; however, with a properly performed osteotomy, complications are relatively few. Ippolito et al. in 1990 reported long-term follow-up of patients with supracondylar osteotomies, 50% of whom had poor results. Increasing deficit has been reported after osteotomy in young children.
The results of different types of osteotomies done to correct cubitus varus are shown in (table 2), the success rate varies from 100%, to 54.2%.