Maria A Stefanou, Dimitrios Pasparakis, Chrisa Tzoumaka- Bakoula, Nikolaos Papandreou, 2 nd Orthopaedic Department ‘Panayiotis & Aglaia Kyriakou’ Children’s Hospital, Athens, Greece Dimitrios Mastrokalos, Panayiotis J Papagelopoulos, 1 st Ortho- paedic Department, University General Hospital ‘Attikon’, Athens, Greece Correspondence to: Maria A. Stefanou, MD, MS, 2 nd Orthopae- dic Department ‘Panayiotis & Aglaia Kyriakou’ Children’s Hospital, 9, Gelonos st, 11521, Athens, Greece Email: maria_stefanou@hotmail.com Telephone: +30-6937-888-030 Received: September 30, 2014 Revised: October 25, 2014 Accepted: October 30, 2014 Published online: December 23, 2014 ABSTRACT AIM: The effectiveness of the Ilizarov ring fixator in correcting achondroplasia’s lower limb deformities is known. However, whether the long term postoperative result is comparable to normal population standards, has not been analyzed. MATERIALS AND METHODS: Nineteen (19) achondroplastic patients, 12 males and 7 females, aged 19-38 years, who at the age of 9-19 years, had undergone both tibia and femur lengthening, using the Ilizarov method, were included in the study. Patients were evaluated 5-19 years after their last surgery, using standardized long lower limb anteroposterior and lateral standing radiographs. Tibial and femoral lengthening gain was measured. A comparison between the achondroplastic patients at follow up and comparative radiographic parameters of the normal population was made, concerning– at the frontal plane- LPFA (lateral proximal femoral angle), LDFA (lateral distal femoral angle), MPTA (medial proximal tibial angle), LDTA (lateral distal tibial angle) and MAD (mechanical axis deviation) and – at the sagittal plane- PDFA (posterior distal femoral angle), PPTA (posterior proximal tibial angle) and ADTA (anterior distal tibial angle). RESULTS: Mean angle values at follow up were: LPFA 118, LDFA 95.5, MPTA 87.8, LDTA 93, PDFA 85.1, PPTA 84, ADTA 88.3 while MAD mean value was 28. LPFA, LDFA, LDTA, PPTA, ADTA and MAD values were statistically significantly different (p<0.001) between achondroplastic patients and normal population. CONCLUSIONS: The use of the Ilizarov method for lower limb deformity correction, in achondroplastic patients, provides a functional length gain. It substantially corrects the three-dimensional deformities of the disease but, it does not restore the radiological image within normal standards. Level of Evidence Level II, Retrospective Prognostic study. © 2014 ACT. All rights reserved. Key words: Achondroplasia; Lower limb lengthening; Deformity; Ilizarov Stefanou MA, Pasparakis D, Mastrokalos D, Tzoumaka-Bakoula C, Papandreou N, Papagelopoulos PJ. Radiographic Assessment of Lower Limb Lengthening in Achondroplastic Patients, Using the Il- izarov Frame: A 5-19 Year Follow up Study. International Journal of Orthopaedics 2014; 1(4): 140-145 Available from: URL: http://www. ghrnet.org/index.php/ijo/article/view/975 INTRODUCTION Achondroplasia, the most common form of dwarfism, is characterized by defective endochondral ossification, due to defect in the gene- located at the end of the short arm of chromosome 4- that encodes for fibroblast growth factor receptor-3 [1] . The disease’s prevalence in the US is 0.36-0.6/10.000 live births [2] and no satisfactory pharmaceutical causal form of treatment has been found. The patients are characterized by rhizomelic short-limbed stature, lumbar lordosis, forehead prominence and a low nasal bridge [3] . Achondroplastic patients have a normal life expectancy [4] . Radiographic Assessment of Lower Limb Lengthening in Achondroplastic Patients, Using the Ilizarov Frame: A 5-19 Year Follow up Study Maria A Stefanou, MD, MS, Dimitrios Pasparakis, MD, PhD, Dimitrios Mastrokalos, MD, PhD, Chrisa Tzoumaka- Bakoula, MD, PhD, Nikolaos Papandreou, MD, PhD, Panayiotis J Papagelopoulos, MD, PhD 140 Int Journal of Orthopaedics 2014 December 23 1(4): 140-145 ISSN 2311-5106 (Print), ISSN 2313-1462 (Online) Online Submissions: http://www.ghrnet.org/index./ijo/ doi:10.6051/j.issn.2311-5106.2014.01.33 © 2014 ACT. All rights reserved. International Journal of Orthopaedics ORIGINAL ARTICLE