Surgical treatment for lumbar canal stenosis in adult achondroplasia

Abstract

Introduction: Achondroplasia is the most common form of human short-limbed dwarfism caused by mutations in theFGFR3 gene, with an incidence of 1 in 30,000 live births annually in global.Achondroplasia is characterized by foramen magnum stenosis, thoracolumbar kyphosis, spinal stenosis, shortened pedicles, genu varum, and short stature. Methods: We report a female, 51 years old, with lumbar canal stenosis due to degenerative disc disease and achondroplasia. We decided to perform decompression (laminectomy) and posterior stabilization. Post-operatively, we observed the general condition of the patient, neurovascular complication, Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), implant position and spinal structure condition. Results: There was no neurovascular complication following the surgery. Mean VAS score of the leg pain improved from 5 to 2. ODI scores also improved consecutively from 18 out of 45 (40%) to 8 out of 45 (17,7%). The sensory function at the L5 and S1 dermatome region of the right leg was improved, as well as the radiological evaluation. Conclusion: Decompression followed by posterior stabilization in a one-stepsurgery isan effective surgical modality to treat lumbar canal stenosis in achondroplastic patients. However, pedicle screw instrumentation in patients with achondroplasia and short stature can be challenging. Safe insertion requires technical experience and knowledge of the achondroplastic pedicle morphometry, which differs markedly from that of the normal spine.