Background The foot is one of the most complex components of musculoskeletal system, and also one of the less addressed in literature. However, its importance in daily activities (gait, posture, etc) has led to a growing concern in understanding the functional mechanisms and joint kinetics of the foot. Foot involvement, whether articular or enthesopatic, is well known in axial spondyloarthritis (aSpa) and peripheral spondyloartrhritis (pSpa). However, data on literature are scarce, and the true impact in patients is unknown.
Objectives To determine the prevalence of functional impairment of the foot and tibiotarsal joint in a cohort of patients with aSpa and pSpa and its relation with disease duration, activity and function indexes.
Methods Cross sectional study. Analyzed variables: gender, age and disease duration. Every patient answered the FAOS (Foot and Ankle Outcome Score) questionnaire, which assesses pain, functional aspects of the foot and tibiotarsal joint and its impact on quality of life and daily activities. In patients with aSpa, BASDAI and BASFI were obtained, as well as DAS28 in patients with pSpa. Control group: healthy individuals, adjusted by gender and age to patients. Statistical analysis with SPSS® version 18.0
Results Eighty patients were enrolled (38 with aSpa and 42 with pSpa), 50 males and 30 females; mean age was 47.3±14.24 years old and mean disease duration was 8.96±10.02 years. Mean DAS28 was 2.49±1.08, mean BASFI was 3.67±2.55 and mean BASDAI was 4.35±2.32. Mean FAOS was 85.5±11.1 on aSpa (mild symptoms) and 77.6±16.1 on pSpa (mild to moderate symptoms).
Compared to control group, pSpa patients had lower FAOS values (p<0.03); this difference wasn't statistically significant with aSpa patients.
Although lower FAOS values were found in females and older patients, this difference wasn't statistically significant.
A statistically significant negative correlation was found between FAOS values and disease duration in pSpa patients (p<0.03).
A statistically significant negative correlation was also found between disease activity and FAOS values (p<0.04 in aSpa and p<0.02, in pSpa); BASFI values also correlated negatively with FAOS (p<0.04).
Conclusions In our cohort, most of patients assumed the presence of mild to moderate functional impairment, especially those with pSpa, as expected. Foot involvement seems to relate directly with disease activity, in both aSpa and pSpa, and with disease duration in pSpa.
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Sawacha Z et al. Biomechanical assessment of balance and posture in subjects with ankylosing spondylitis; J Neuroengineering Rehabil. 2012;9:63
Disclosure of Interest None declared