Cross Lengthening

It is the commonest form of short limbed dwarfism. It is most amenable to lengthening and if treatment is started early, a significant amount of height can be achieved and significant social stigma associated with dwarfism can be avoided. These children do not grow more than 12 year old child having Achondroplasia and short limbed dwarfism is hardly 3’9″ Unfortunately, she was informed by a famous Paediatric Orthopaedic Surgeon that lengthening should wait unitl maturity–an advice which fails to recognize problems due to waiting and delaying the lengthening.

Cross Lengthening is one of the methods of treatment which minimizes morbidity and maximizes amount of length achieved in the smallest time period. The tibia was lengthened in a double level manner and the femur in a single level using the Ilizarov fixator. It is the best method for lengthening the tibia  without deformities and the femur is easitly manageable for younger children.Since they decided to perform the entire amount of length, it was decided to perform the Cross Lengthening method. The tibia was lengthened with Double level lengthening and the opposite femur lengthened in a single level lengthening.

At the end of the first stage, She achieved 12.5 cm or 5 inches of length in the tibia and 10 cm or 4 inches in the femur. At the end of the first stage the discrepancy is minimal.

The second stage of cross lengthening is easier to tolerate and walking is not difficult during treatment. After a small break, the opposite pair is lengthened to the same extent. Walking is possible with a walker and knee bending and ankle exercises are possible. Comfort levels are reasonable and with proper nursing and modifications to the bed and help from parents, significant length can be achieved without significant pain.

Total amount of height gained is 9 inches without significant complications and gives a lot of confidence and happiness. Ideally this treatment should be started very early in life. At the end of the two stages in which both femurs and both tibiae were lengthened to more than 22.5 cm or 9 inches she is happy and more confident of dealing with the world.

Distraction Osteogenesis for Lengthening of the Tibia in Patients Who Have Limb-Length Discrepancy or Short Stature
ROBERTO ALDEGHERI
J. Bone Joint Surg. Am., May 1999; 81: 624 – 34

Distraction Osteogenesis of the Lower Extremity with Use of Monolateral External Fixation. A Study of Two Hundred and Sixty-one Femora and Tibiae
KENNETH J. NOONAN, MANUEL LEYES, FRANCISCO FORRIOL, and JOSE CAÑADELL
J. Bone Joint Surg. Am., Jun 1998; 80: 793 – 806.

The Effect of Distraction-Resisting Forces on the Tibia During Distraction Osteogenesis
Ashok K. Shyam, Hae-Ryong Song, Hyonggin An, Dileep Isaac, Gautam M. Shetty, and Seok Hyun Lee J. Bone Joint Surg. Am., Jul 2009; 91: 1671 – 1682.