Author Heng, Marabelle Li-Wen
Title Mobility and posterior tibial tendon dysfunction (PTTD) in persons with flat foot: a case control study
Institute Thesis (M.Sc.) National Institute of Education, Nanyang Technological University
Year 2015
Supervisor Kong, Veni Pui Wah

Posterior tibial tendon dysfunction (PTTD) is a progressive and debilitating condition. Flat foot is a known associated factor of PTTD but there are still many questions about the biomechanical etiology of PTTD. Hypermobility in the first ray and first metatarsophalangeal joint (MPJ) is thought to be a causative factor in various foot pathologies including PTTD, however the association is not well established. To date, clinical assessment of hypermobility is still done by subjective estimation because commercially clinical instrumentation to measure mobility is not available. This study aimed to (i) investigate whether hypermobility is associated with development of PTTD in flat footed persons, (ii) report a novel technique of quantifying the stiffness of foot joints and (iii) examine relationship between subjective clinical assessment methods and objective stiffness measurements. Sixteen flat footed subjects exhibiting PTTD symptoms were compared with sixteen asymptomatic flat-footed controls matched for age, sex and body mass index. The results of this study showed that there were no significant differences between median joint stiffness scores of the PTTD group and control group [first ray stiffness PTTD Group: 0.64 (0.57) N/mm; first ray stiffness Control Group: 0.63 (1.05) N/mm; p = .72; first MPJ stiffness PTTD Group: 11.6 (13.3) Nmm/o; first MPJ stiffness Control Group: 11.0 (6.23) Nmm/o; p = .96]. The manual clinical assessment findings also showed similar joint mobility between the two groups. In conclusion, the results of this study suggest that foot joint mobility is not associated with PTTD.