Correlations between weight‐bearing 3D bone architecture and dynamic plantar pressure measurements in the diabetic foot

Abstract

Background Measurements of plantar loading reveal foot-to-floor interaction during activity, but information on bone architecture cannot be derived. Recently, cone-beam computer tomography (CBCT) has given visual access to skeletal structures in weight-bearing. The combination of the two measures has the potential to improve clinical understanding and prevention of diabetic foot ulcers. This study explores the correlations between static 3D bone alignment and dynamic plantar loading. Methods Sixteen patients with diabetes were enrolled (group ALL): 15 type 1 with (N, 7) and without (D, 8) diabetic neuropathy, and 1 with latent autoimmune diabetes. CBCT foot scans were taken in single-leg upright posture. 3D bone models were obtained by image segmentation and aligned in a foot anatomical reference frame. Absolute inclination and relative orientation angles and heights of the bones were calculated. Pressure patterns were also acquired during barefoot level walking at self-selected speed, from which regional peak pressure and absolute and normalised pressure-time integral were worked out at hallux and at first, central and fifth metatarsals (LOAD variables) as averaged over five trials. Correlations with 3D alignments were searched also with arch index, contact time, age, BMI, years of disease and a neuropathy-related variable. Results Lateral and 3D angles showed the highest percentage of significant (p < 0.05) correlations with LOAD. These were weak-to-moderate in the ALL group, moderate-to-strong in N and D. LOAD under the central metatarsals showed moderate-to-strong correlation with plantarflexion of the 2nd and 3rd phalanxes in ALL and N. LOAD at the hallux increased with plantarflexion at the 3rd phalanx in ALL, at 1st phalanx in N and at 5th phalanx in D. Arch index correlated with 1st phalanx plantarflexion in ALL and D; contact time showed strong correlation with 2nd and 3rd metatarsals and with 4th phalanx dorsiflexion in D. Conclusion These preliminary original measures reveal that alteration of plantar dynamic loading patterns can be accounted for peculiar structural changes of foot bones. Load under the central metatarsal heads were correlated more with inclination of the corresponding phalanxes than metatarsals. Further analyses shall detect to which extent variables play a role in the many group-specific correlations.

The Effect of Neuropathy and Diabetes Type on Multisegment Foot Kinematics: A Cohort Study on 70 Participants with Diabetes

“…This is the one of the few studies reporting multisegment foot kinematics on a rather large population with diabetes which were grouped by diabetes type and by the presence of DPN. In a previous effort by the present authors, several correlations were found between foot morphological parameters, such a decreased metatarsal bone distance from the floor and segments inclination, with respect to plantar-load parameters [37]. To the best of our knowledge, the effects of covariates on foot joints ROM were not accounted for in previous studies thus limiting those investigations to the analysis of populations matched by age or BMI.…”

Angular and linear measurements of adult flexible flatfoot via weight-bearing CT scans and 3D bone reconstruction tools

“…1 ), these hardly can be introduced in routine clinical assessments, which necessarily need a quantitative response in a few minutes; rather, qualitative views of the 3D rendering of the feet can be accessible in a few seconds 31 . On the other hand, the present 3D measurements can be exploited easily in large clinical populations in case of retrospective and prospective clinical studies, as well as in complex biomechanical analyses 13 , 47 .…”

“…All these advancements may also be supported by modern visualisation modalities, for example from virtual-reality or 3D printing. The present techniques and measures shall be combined with other medical imaging 23 and biomechanical 13 , 47 , 56 , 64 analyses, for a thorough 3D radiological and functional assessments of the severity of the pathology and of the effects of treatments. Finally, distance map analyses can detect very carefully how the disruption of the skeletal structure affects the joint surface interactions under load 65 .…”

“…The last processing step, i.e. angular and height measures (see also Table 1 ) were divided into absolute inclination (I) of a single bone, or relative orientation (R) between two adjacent bones 39 , 47 . Both were further divided in 3D measures (3), or planar measures in the lateral (L), frontal (F) or transverse (T) anatomical planes, similarly to what defined traditionally in foot radiographs 8 , 9 .…”

Analysis of Clinical Profiles, Deformities, and Plantar Pressure Patterns in Diabetic Foot Syndrome

“…The model could only explain about 34% of the variance in the local peak pressure. However, the inclusion of foot architecture in the model may be of interest, especially now that innovative foot architecture measurements can be extracted from the weight-bearing CT (WBCT) [11].…”