es planus (PP) and pes cavus (PC) are frequent disorders of the foot. It is known that standing still for a long time, bony and neurological problems such as congenital tarsal coalition and cerebral palsy, trauma, inappropriate shoes, generalized ligamentous laxity, sole disorders in relatives and muscle imbalance all aggravate sole problems. 1-3 Since foot is the contact point during weight bearing and ambulation, the mechanical characteristics of the foot determine the energy transfer into the lower extremity, and therefore it helps to define the pattern of weight bearing and the potential for injury to the lower extremities. The presence of sole problems is the important intrinsic factor in overuse injuries. 4-8 However, numerous studies have indicated that there are neutral or even beneficial effects P From the Department of Sports Medicine (Aydog S, Demirel, Tetik), Department of Physical Medicine and Rehabilitation (Hascelik), Department of Sports Medicine and Orthopedics and Traumatology (Doral), Faculty of Medicine, Hacettepe University, and the Department of Physical Medicine and Rehabilitation (Aydog E), SSK Ankara Education Hospital, Ankara, Turkey. Received 29th December 2003. Accepted for publication in final form 10th March 2004. Address correspondence and reprint request to: Dr. Sedat T. Aydog, Department of Sports Medicine, Hacettepe University, D Kati 06100 Sihhiye, Ankara, Turkey. Tel. +90 (312) 3051347. Fax. +90 (312) 3051347. E-mail: taydog@hacettepe.edu.tr ABSTRACT associated with PP. 1,9 Finally, effects of foot types on injuries are controversial, but the detection and correction of these problems may reduce these injuries. Staheli et al 9 found that the medial longitudinal arch has an undulating pattern according to age and arch indices (AI). The AI is approximately one (range: 0.7 -1.35) at first year of age, reducing to a minimum of 0.6 (range: 0.3-0.9) at 12-14 years of age, before increasing to 0.8 (range: 0.3-1.1) at older ages. 9,10 The medial longitudinal arch starts at the weight-bearing surface of the calcaneus and ends at the metatarsal heads. It is supported by passive (bone and ligaments) and active structures (muscles). In a standing position, few intrinsic or extrinsic muscles activity occur, and the arch is maintained primarily by passive Sedat T. Aydog, MD, PhD, Haydar A. Demirel, MD, PhD, Onur Tetik, MD, Ece Aydog, MD, Zafer Hascelik, MD, Mahmut N. Doral, MD, 1100 Objective: The aim of this study was to find out the difference between sole arch indices of adolescent basketball players and an age matched non-athletic group. Methods: This study was carried out in the Sports Education, Health and Research Center, Ankara, Turkey, between November 1998 and December 1998. In junior (16-18 years) categories 48 male basketball players and 45 age matched controls were included in the study. Body mass index and podoscopic sole images of subjects were recorded, and the arch index was calculated for each group. Results: The sole arch index has no difference between basketball players and controls. The right foot arch index of the control group was 59.62 ± 23.26 and 56.74 ± 17.21 in players (p=0.497). The left foot arch index was 54.54 ± 23.72 in control groups and 55.13 ± 17.33 in players (p=0.890). There was a significant negative correlation between sole arch index and training age in basketball players (r=-0.3312 for right sole arch index, p<0.05; r=-0.3056 for left sole arch index, p<0.05). Conclusion: These results have shown that basketball might result in specific adaptation on sole arches of adolescent players. Saudi Med J 2004; Vol. 25 (8): 1100-1102