title: Anatomy and biomechanical properties of the plantar aponeurosis: a cadaveric study.
abstract: OBJECTIVE
  To explore the anatomy of the plantar aponeurosis (PA) and its biomechanical effects on the first metatarsophalangeal (MTP) joint and foot arch.
  
  
  METHODS
  Anatomic parameters (length, width and thickness of each central PA bundle and the main body of the central part) were measured in 8 cadaveric specimens. The ratios of the length and width of each bundle to the length and width of the central part were used to describe these bundles. Six cadaveric specimens were used to measure the range of motion of the first MTP joint before and after releasing the first bundle of the PA. Another 6 specimens were used to evaluate simulated static weight-bearing. Changes in foot arch height and plantar pressure were measured before and after dividing the first bundle.
  
  
  RESULTS
  The average width and thickness of the origin of the central part at the calcaneal tubercle were 15.45 mm and 2.79 mm respectively. The ratio of the length of each bundle to the length of the central part was (from medial to lateral) 0.29, 0.30, 0.28, 0.25, and 0.27, respectively. Similarly, the ratio of the widths was 0.26, 0.25, 0.23, 0.19 and 0.17. The thickness of each bundle at the bifurcation of the PA into bundles was (from medial to lateral) 1.26 mm, 1.04 mm, 0.91 mm, 0.84 mm and 0.72 mm. The average dorsiflexion of the first MTP joint increased 10.16° after the first bundle was divided. Marked acute changes in the foot arch height and the plantar pressure were not observed after division.
  
  
  CONCLUSIONS
  The first PA bundle was not the longest, widest, or the thickest bundle. Releasing the first bundle increased the range of motion of the first MTP joint, but did not acutely change foot arch height or plantar pressure during static load testing.
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Da-wei
authors.initials: DW
authors.lastname: Chen
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Ashwin
authors.initials: A
authors.lastname: Aubeeluck
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Yun-feng
authors.initials: YF
authors.lastname: Yang
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Yi-gang
authors.initials: YG
authors.lastname: Huang
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Jia-qian
authors.initials: JQ
authors.lastname: Zhou
authors.affiliation: Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, China.
authors.forename: Guang-rong
authors.initials: GR
authors.lastname: Yu
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D002111:Calcaneus / Q000033:anatomy & histology / Q000502:physiology; D005528:Foot / Q000033:anatomy & histology* / Q000502:physiology*; D006801:Humans; D008683:Metatarsophalangeal Joint / Q000033:anatomy & histology / Q000502:physiology; D008875:Middle Aged; D016059:Range of Motion, Articular; D016474:Weight-Bearing