Achondroplasia

The diagnosis is made in utero by chance on an ultrasound scan in the third trimester of pregnancy. In pregnancies when achondroplasia is suspected by ultrasound, the final diagnosis is made by fetal DNA testing with detection of the FGFR3 gene mutation. Preimplantation diagnosis is possible in specialized laboratories. After birth, clinical and radiographic evaluation reveals typical morphological changes, namely rhizomelia, generalized metaphyseal abnormalities, narrowing of the intervertebral distance of the lower lumbar vertebrae, abnormal pelvis with small square-shaped iliac wings, narrow sacroiliac incisura.

Currently, there are no specific treatments except for the possibility of surgical limb lengthening to achieve growth that provides a better quality of life. This goal is achieved gradually through osteotomy operations and the use of external fixators, distraction and fixation devices placed outside the limb, which are then removed once bone consolidation is complete. Lengthening primarily affects the lower extremities and may involve the upper extremities at a later stage to limit the disproportion between the segments. The total number of operations is divided into 4 stages for the lower extremities and only 1 for the upper extremities. Each of these stages, which lengthens approximately 1/3 of the original length of the treated segment, takes an average of 8 to 12 months. This process involves a lengthy surgical and rehabilitative procedure that affects the life of the patient and his family, and is preferably performed at school age and is preceded by adequate cognitive, emotional and psychological preparation with dedicated staff.

• First stage of bilateral tibial lengthening
• First stage of bilateral femoral lengthening
• Second stage of bilateral tibia lengthening
• Second stage of bilateral femoral lengthening
• Possible stage of bilateral humerus lengthening