Biomechanical and Morphological Characterization of PTTD (PTTD)

Biomechanical and Morphological Characterization of the Foot in Patients With Posterior Tibial Tendon Dysfunction.

Posterior tibial tendon dysfunction (PTTD) is a progressive condition of the tendon of the tibialis posterior muscle with symptoms of tendinopathy or even rupture. Functionally, it is associated with the inability to lock the mid foot and thus manifests itself as a main contributor to adult acquired flatfoot deformity.

Concerning treatment, clinical decision making is currently based on a classification integrating various parameters as pain, flexibility of the foot joints, the condition of the posterior tibial tendon assessed through ultrasound imaging and radiographic assessment of arthritic changes. Surprisingly, this classification does not consider any morphologic characteristics (the shape of a bone or joint) or functional, biomechanical characteristics of the foot and ankle, i.e. based on kinematics (e.g. range of motion) and/or kinetics (center of pressure, angular velocity, moment, power absorption and power generation of a joint).

Detailed biomechanical characteristics of the foot and ankle can be reliably collected by instrumented gait analysis wherein a 3D camera system is combined with a force plate and plantar pressure platform. Kinematic studies in the field of PTTD typically considered the foot as a structure consisting of three segments: hind foot, forefoot and hallux. Consequently, the mid foot segment (the Chopart and Lisfranc joints) has been neglected, although it is this segment that is particularly affected in PTTD patients.

The aim of this research is to overcome the limitations of the current classification system and treatment of PTTD patients, by complementing the current standard-of-care clinical assessment with better insight in the pathologic changes that occur in PTTD patients.

Study Overview

• Status: Recruiting
• Conditions: Posterior Tibial Tendon Dysfunction
• Intervention / Treatment: Diagnostic test: Radiography; Diagnostic test: Ultrasound; Diagnostic test: MRI; Diagnostic test: CT-scan; Diagnostic test: Gait analysis

Detailed Description

Posterior tibial tendon dysfunction (PTTD) is a progressive condition of the tendon of the tibialis posterior muscle with symptoms of tendinopathy or even rupture. Functionally, it is associated with the inability to lock the mid foot and thus manifests itself as a main contributor to adult acquired flatfoot deformity. Importantly, this condition is associated with severe pain, inability to walk, collapse of the foot arch and dislocation and destruction of foot joints, causing serious disability with respect to activities of daily living and professional activities.

Concerning treatment, clinical decision making is currently based on a classification integrating various parameters as pain, flexibility of the foot joints, the condition of the posterior tibial tendon assessed through ultrasound imaging and radiographic assessment of arthritic changes. PTTD stage 1 is characterized by tendinopathy and is suggested to be mainly treated conservatively. Stage 2 is characterized by a flexible flat foot deformation, mostly combined with a tear of the posterior tibial tendon. Here, treatment is suggested through osteotomies and soft tissue surgery. Stage 3 encompasses a rigid flat foot deformity associated with a fully dysfunctional posterior tibial tendon and degenerative changes of the hind foot joints. At this stage fusion of the affected joints should be considered. During recent decades, this classification has been extended with additional subgroups as well as a stage 4 which adds onto stage 3 with excessive tibio-talar valgus and is mainly treated by a complementary fusion of the ankle joint.

Surprisingly, this classification does not consider any morphologic characteristics (the shape of a bone or joint) or functional, biomechanical characteristics of the foot and ankle, i.e. based on kinematics (e.g. range of motion) and/or kinetics (center of pressure, angular velocity, moment, power absorption and power generation of a joint).

Detailed biomechanical characteristics of the foot and ankle can be reliably collected by instrumented gait analysis wherein a 3D camera system is combined with a force plate and plantar pressure platform. Kinematic studies in the field of PTTD typically considered the foot as a structure consisting of three segments: hind foot, forefoot and hallux. Consequently, the mid foot segment (the Chopart and Lisfranc joints) has been neglected, although it is this segment that is particularly affected in PTTD patients. While kinematic studies focus on joint motion, kinetic studies focus on the loading and impact associated with motion of the joints.

Besides documenting specific biomechanical characteristics of the different stages of PTTD, it is essential to explore the relation of these biomechanical characteristics with the bone morphology of the involved osseous structures.

The aim of this research is to overcome the limitations of the current classification system and treatment of PTTD patients, by complementing the current standard-of-care clinical assessment with better insight in the pathologic changes that occur in PTTD patients. This will be done by simultaneously acquiring kinematic, kinetic and morphologic characteristics in PTTD patients, with a special interest in the possible connection between these morphological and the biomechanics changes. Through these insights, we will be able to better classify these patients, using the developed biomechanical classification, as a first step towards an optimized, patient-tailored treatment plan which converts these individual pathological characteristics back to normal, giving the patients back their mobility and a live without pain, i.e. gaining back their quality of life.

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Sander Wuite; Phone Number: +32 16 33 83 29; Email: sander.wuite@uzleuven.be
• Study Contact Backup: Name: Kevin Deschamps; Phone Number: +32 16 33 88 27; Email: kevin.deschamps@uzleuven.be

Study Locations

• Belgium
  • Vlaams-Brabant
    • Leuven, Vlaams-Brabant, Belgium, 3000
      • Recruiting
      • UZ Leuven
      • Contact: Sander Wuite; Phone Number: +32 16 33 83 29; Email: sander.wuite@uzleuven.be
      • Contact: Kevin Deschamps; Phone Number: +32 16 33 88 27; Email: kevin.deschamps@uzleuven.be

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion criteria:

• Patient groups:

  • Posterior tibial tendon dysfunction (all clinical stages)
  • Age 18-675 year
  • ICF obtained

• Control group:

  • No pain complaints
  • No pes plano valgus, PTTD or pes cavo varus or other foot and ankle pathology
  • Age 18-75 year
  • ICF obtained

Exclusion criteria patient and control groups:

• Being younger than 18 years
• Inability to walk without mobility aids
• Inability to walk < 100 meter
• Difference in leg length > 3cm
• Subjects with BMI>30 kg/m², due to less accurate gait analysis by absence of anatomical landmarks
• Subjects unable to perform a gait analysis
• Any medical condition possibly affecting normal gait.
• Pregnancy: at the start or during the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: PTTD patients (PTTD I, II and III); 75 patients with PTTD (25 patients in Stage I, 25 patients in Stage II, 25 patients in Stage III)	Diagnostic test: Radiography; X-rays of the ankle; anterior-posterior, lateral, Mortise view and hindfoot alignment view. Standard weight bearing x-rays of the foot; anterior-posterior, lateral and oblique view.; Diagnostic test: Ultrasound; Ultrasound of the posterior tibial tendon to see if there is an irritation, elongation or rupture.; Diagnostic test: MRI; MRI when ultrasound is not conclusive to identify an irritation, elongation or rupture of the posterior tibial tendon.; Diagnostic test: CT-scan; CT-scan to identify arthritis of the tibial-talar, subtalar and/or Chopart joints.; Diagnostic test: Gait analysis; This lab is equipped with a 10-meter walkway surrounded by a passive optoelectronic motion analysis system consisting of 10 cameras to track the motion of markers. In the middle of the walkway, a force plate is integrated, with a pressure plate placed on top.
Experimental: Healthy control group; 25 healthy volunteers	Diagnostic test: Radiography; X-rays of the ankle; anterior-posterior, lateral, Mortise view and hindfoot alignment view. Standard weight bearing x-rays of the foot; anterior-posterior, lateral and oblique view.; Diagnostic test: CT-scan; CT-scan to identify arthritis of the tibial-talar, subtalar and/or Chopart joints.; Diagnostic test: Gait analysis; This lab is equipped with a 10-meter walkway surrounded by a passive optoelectronic motion analysis system consisting of 10 cameras to track the motion of markers. In the middle of the walkway, a force plate is integrated, with a pressure plate placed on top.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Kinematic characteristics during Gait analysis	Range of Motion (ROM) of PTTD patient of each stage will be obtained and compared between the patient groups (PTTD 1-2-3) and a control group.	1 year
Center of pressure during Gait analysis	The center of pressure (kinetic characteristic) of PTTD patients of each stage will be obtained and compared between the patient groups (PTTD 1-2-3) and a control group. This information can be reliably collected by instrumented gait analysis wherein a 3D camera system is combined with a force plate and plantar pressure platform.	1 year
Angular velocity during Gait analysis	The angular velocity (kinetic characteristic) of PTTD patients of each stage will be obtained and compared between the patient groups (PTTD 1-2-3) and a control group. This information can be reliably collected by instrumented gait analysis wherein a 3D camera system is combined with a force plate and plantar pressure platform.	1 year
Moment during Gait analysis	The moment (kinetic characteristic) of PTTD patients of each stage will be obtained and compared between the patient groups (PTTD 1-2-3) and a control group. This information can be reliably collected by instrumented gait analysis wherein a 3D camera system is combined with a force plate and plantar pressure platform.	1 year
Power absorption during Gait analysis	The power absorption (kinetic characteristic) of PTTD patients of each stage will be obtained and compared between the patient groups (PTTD 1-2-3) and a control group. This information can be reliably collected by instrumented gait analysis wherein a 3D camera system is combined with a force plate and plantar pressure platform.	1 year
Power generation during Gait analysis	The power generation (kinetic characteristic) of PTTD patients of each stage will be obtained and compared between the patient groups (PTTD 1-2-3) and a control group. This information can be reliably collected by instrumented gait analysis wherein a 3D camera system is combined with a force plate and plantar pressure platform.	1 year
Bone morphology	Morphological characteristics of PTTD patients of each stage will be obtained by CT-scan and statistical shape modeling and compared between the study groups and a control group.	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
American Orthopaedic Foot & Ankle Society (AOFAS) score	Patients Reported Outcome Measures. It combines five patient-reported items concerning pain and function with four physician-determined items concerning function and alignment, on a 0 to 100-point scale with healthy ankles receiving 100 points.	1 year
European Foot and Ankle Society (EFAS) score	Patients Reported Outcome Measures consisting of six questions on pain and function. A total of 24 points can be achieved on a 5-point scale (0-4), whereby a high score means a good result.	1 year
36-item Short Form Health Survey (SF36)	Patients Reported Outcome Measures that measures health-related quality of life and health care needs. The instrument includes scales for physical functioning, social functioning, role limitations due to physical or emotional problems, mental health, energy, pain and general health perception. A high score corresponds to better health status.	1 year
Visual Analogue Scale (VAS) pain	Patients Reported Outcome Measures to quantify the pain of a patient. The VAS pain score runs from 10 to 0, where 10 is "Worst possible pain" and 0 is "No pain".	1 year
Visual Analogue Scale (VAS) satisfaction	Patients Reported Outcome Measures to quantify the satisfaction of a patient. The VAS satisfaction score runs from 10 to 0, where 10 is "Very satisfied" and 0 is "unsatisfied".	1 year

Collaborators and Investigators

• Sponsor: Universitaire Ziekenhuizen KU Leuven
• Investigators: Principal Investigator: Sander Wuite, Universitaire Ziekenhuizen KU Leuven

Study record dates

Study Major Dates

• Study Start (Actual): August 22, 2022
• Primary Completion (Estimated): August 1, 2028
• Study Completion (Estimated): August 1, 2028

Study Registration Dates

• First Submitted: December 8, 2023
• First Submitted That Met QC Criteria: February 12, 2024
• First Posted (Actual): February 15, 2024

Study Record Updates

• Last Update Posted (Actual): April 15, 2025
• Last Update Submitted That Met QC Criteria: April 10, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Foot Diseases; Posterior Tibial Tendon Dysfunction
• Other Study ID Numbers: S66277

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No