A systematic review published in The bone and Joint Journal, May 2014

Supracondylar osteotomy for treatment of cubitus varus in children

Presented by : Harjot Singh GurudattaModerator : DR. GAGAN KHANNA

INTRODUCTION

Cubitus varus is the most common significant late complication of supracondylar fracture. This deformity typically represents fracture malunion and rarely results from partialgrowth arrest of the medial condylar growth plate. Malunion may be avoided by careful attention to anatomic reduction and secure fixation at the time of initial management. Cubitusvarus is generally considered a cosmetically acceptable deformity, but increased risk of lateral condyle fracture, tardy ulnar palsy, posterolateral rotary instability of the elbow, and posteriorshoulder instability has also been reported. Also, increased awareness among parents has resulted in more children seeking attention

An increased risk of fracture,especially of the lateral condyle, has been linked with cubitusvarus deformity.

WHY OPERATE?

tardy posterolateral rotatory instabilityLess flexion and hyperextention

Tardy ulnar nerve palsy also has been associated with cubitus varus and internal rotational malalignment. With a cubitusvarus deformity, the olecranon fossa moves to the ulnar side of the distal humerus, and the triceps shifts a bit ulnarward. Investigators theorized that this ulnar shift might compress the ulnar nerve against the medial epicondyle, narrowing the cubital tunnel and resulting in chronic neuropathy. Also, a fibrous band running between the heads of the flexor carpi ulnariswas thought to cause ulnar nerve compression.

TREATMENT OPTIONS

Medial displacement and rotation of the distal fragment have been cited most often, but experimental studies showed that varus tilting of the distal fragment was the most importantcause of change in the carrying angle. Other suggested causes include varus tilting of the distal fragment and growth disturbance in the distal humerus, especially overgrowth of thelateral condyle. Osteonecrosis and delayed growth of the trochlea, with relative overgrowth of the normal lateral side of the distal humeral epiphysis, is a rare cause of progressivecubitus varus deformity after supracondylar fracture.

Accordingly, We can either go for(i) observation with expected remodeling, (ii) hemiepiphysiodesis and growth alteration, and (iii) corrective osteotomy.

Observation is not recommened in this era.Hemiepiphysiodesis is also seldom recommended as the distal humerus accounts for only 20% of Humeral growth and even less in the >6yrs age group.

Three basic types of osteotomies have been described:a medial opening wedge osteotomy with a bone graft, anoblique osteotomy with derotation, and a lateral closingwedge osteotomy. The latter being the most popular.

This study is a metaanalysis of various studies conducted for cubitus varus deformity correction. A total of 330 studies were shortlisted out of which 40 were selected for this analysis based on no. of cases, age, operative technique and many other factors.

Outcome assessment was done according to the correction achieved, ROM attained,alignment,complications, function etc.

Major complications included Residual deformity, nerve injury, infection, loss of fixation, stiffness.

Good correction with <5 deg varus with good function without pain and no complications were included as excellent result

RESULTS

Lateral wedge osteotomy was the main method of treatment in 24 of the studies, with 473 patients resulting in 84% excellent results

Distraction osteogenesis was done in 2 studies, 37 patients with equivalent results.Dome and complex(multiplanar) osteotomy done in 7 studies, 100 patients with 90% excellent results.

The most common fixation method used were k wires(46%), ex-fix(12%), Tension band with screws(11%), screw(8%), plates(4%).

Mean preop carrying angle was 20 deg varus and postop 7 deg valgus, with around 27 degcorrection.Mean time to union was 8 weeks, and mean ROM improved by 20 deg.Nerve injury incidences and infection were uncommon mean being 2 % in all groups.Most common complication was residual varus , Being 6% in all groups

As far as fixation method is concerned , 20% of those with k – wires sustained complications(infection(3%), residual varus(10%), loss of fixation).Screws alone and Ex-fix had the lowest complications., But the p value was insignificant.

Approach also had no differnce in complications with 2% nerve injuries in all post med or latapproach

This study found the results to be similar in all study groups in terms of complications, and effectiveness.

This study recommends the surgeons to chose the method of treatment with care and as per the norms in their locality, practice and teaching. It is most important to take the parents in confidence with detailed discussions regarding the possible complications, fixation method, functional outcome and residual deformity