HV Patients Show Greater Pronation of the First Metatarsal than Normals

Category: Basic Sciences/Biologics, Bunion, Midfoot/Forefoot Introduction/Purpose: The progression of the hallux valgus (HV) deformity demonstrates dorsiflexion and abduction; concomitant pronation has not received adequate documentation and the extent of pronation in the pathology is unknown even t...

Full description

Bibliographic Details
Main Authors: Bradley Campbell MS, Stephen Conti MD
Format: Article
Language:English
Published: SAGE Publishing 2017-09-01
Series:Foot & Ankle Orthopaedics
Online Access:https://doi.org/10.1177/2473011417S000030
_version_ 1818129444868456448
author Bradley Campbell MS
Stephen Conti MD
author_facet Bradley Campbell MS
Stephen Conti MD
author_sort Bradley Campbell MS
collection DOAJ
description Category: Basic Sciences/Biologics, Bunion, Midfoot/Forefoot Introduction/Purpose: The progression of the hallux valgus (HV) deformity demonstrates dorsiflexion and abduction; concomitant pronation has not received adequate documentation and the extent of pronation in the pathology is unknown even though correction of the deformity may need to address all three angles. To overcome the inability of standard radiographs to capture pronation, we have developed a means to assess the three dimensional deformity using CT scans. Our goal was to document the extent of pronation/supination both of the first phalanx with respect to the first metatarsal and of the first metatarsal with respect to the second metatarsal. Furthermore, we wanted to regress pronation against the intermetatarsal (IMA) angle of hallux valgus patients. Methods: Three-dimensional models were reconstructed from loaded and unloaded CT files of patients (10 HV, 10 normal). The orientations of specific bones, in anatomic directions, were determined by selecting landmarks on the surface of the phalanx and of the first and second metatarsals. The resulting calculations output a set of angles to determine the pronation/supination of the first metatarsal relative to the second and of the first phalanx relative to the first metatarsal. A regression analysis was conducted to extrapolate any relationship between adduction and pronation (known intermetatarsal and pronation). Results: The average pronation of the first metatarsal relative to the second metatarsal was 19.8 ± 7.1 and 28.3 ± 10.8 in the normal and HV groups respectively (p < 0.05). The influence of weightbearing demonstrated pronation angle differences that were greater in the normal group than in the HV group for both the IM pronation and the HV pronation (p < 0.05) (Figure 1). The differences in HV angles and IM angles between normal and HV patients were 22° and 7° respectively. The regression analysis of the pronation and intermetatarsal angle was not found to be significant, with a weak correlation (r2 = 0.26). Conclusion: The pronation of the first metatarsal relative to the second metatarsal between normal and HV patients is significantly different. While the first metatarsal had measurable pronation in patients with hallux valgus but that value was not predicted by the IMA. The findings of this study indicate pronation should be considered in any surgical technique that seeks to restore native configurations.
first_indexed 2024-12-11T07:49:15Z
format Article
id doaj.art-9b21c414b7c84295abddc54b42df56fc
institution Directory Open Access Journal
issn 2473-0114
language English
last_indexed 2024-12-11T07:49:15Z
publishDate 2017-09-01
publisher SAGE Publishing
record_format Article
series Foot & Ankle Orthopaedics
spelling doaj.art-9b21c414b7c84295abddc54b42df56fc2022-12-22T01:15:23ZengSAGE PublishingFoot & Ankle Orthopaedics2473-01142017-09-01210.1177/2473011417S000030HV Patients Show Greater Pronation of the First Metatarsal than NormalsBradley Campbell MSStephen Conti MDCategory: Basic Sciences/Biologics, Bunion, Midfoot/Forefoot Introduction/Purpose: The progression of the hallux valgus (HV) deformity demonstrates dorsiflexion and abduction; concomitant pronation has not received adequate documentation and the extent of pronation in the pathology is unknown even though correction of the deformity may need to address all three angles. To overcome the inability of standard radiographs to capture pronation, we have developed a means to assess the three dimensional deformity using CT scans. Our goal was to document the extent of pronation/supination both of the first phalanx with respect to the first metatarsal and of the first metatarsal with respect to the second metatarsal. Furthermore, we wanted to regress pronation against the intermetatarsal (IMA) angle of hallux valgus patients. Methods: Three-dimensional models were reconstructed from loaded and unloaded CT files of patients (10 HV, 10 normal). The orientations of specific bones, in anatomic directions, were determined by selecting landmarks on the surface of the phalanx and of the first and second metatarsals. The resulting calculations output a set of angles to determine the pronation/supination of the first metatarsal relative to the second and of the first phalanx relative to the first metatarsal. A regression analysis was conducted to extrapolate any relationship between adduction and pronation (known intermetatarsal and pronation). Results: The average pronation of the first metatarsal relative to the second metatarsal was 19.8 ± 7.1 and 28.3 ± 10.8 in the normal and HV groups respectively (p < 0.05). The influence of weightbearing demonstrated pronation angle differences that were greater in the normal group than in the HV group for both the IM pronation and the HV pronation (p < 0.05) (Figure 1). The differences in HV angles and IM angles between normal and HV patients were 22° and 7° respectively. The regression analysis of the pronation and intermetatarsal angle was not found to be significant, with a weak correlation (r2 = 0.26). Conclusion: The pronation of the first metatarsal relative to the second metatarsal between normal and HV patients is significantly different. While the first metatarsal had measurable pronation in patients with hallux valgus but that value was not predicted by the IMA. The findings of this study indicate pronation should be considered in any surgical technique that seeks to restore native configurations.https://doi.org/10.1177/2473011417S000030
spellingShingle Bradley Campbell MS
Stephen Conti MD
HV Patients Show Greater Pronation of the First Metatarsal than Normals
Foot & Ankle Orthopaedics
title HV Patients Show Greater Pronation of the First Metatarsal than Normals
title_full HV Patients Show Greater Pronation of the First Metatarsal than Normals
title_fullStr HV Patients Show Greater Pronation of the First Metatarsal than Normals
title_full_unstemmed HV Patients Show Greater Pronation of the First Metatarsal than Normals
title_short HV Patients Show Greater Pronation of the First Metatarsal than Normals
title_sort hv patients show greater pronation of the first metatarsal than normals
url https://doi.org/10.1177/2473011417S000030
work_keys_str_mv AT bradleycampbellms hvpatientsshowgreaterpronationofthefirstmetatarsalthannormals
AT stephencontimd hvpatientsshowgreaterpronationofthefirstmetatarsalthannormals