The Neglected Midfoot: New Research Guiding Clinical Exam ......Kelly LA, Cresswell AG, Racinais S, Whiteley R, Lichtwark G. Intrinsic foot muscles have the capacity to control deformation

The Neglected Midfoot: New Research Guiding Clinical Exam and Intervention

American Physical Therapy Association Combined Sections Meeting February 17-20, 2016 Anaheim, CA
 Orthopaedic Section
 Foot and Ankle Special Interest Group

Frank DiLiberto PT, PhD, OCS, FAAOMPT Assistant Professor, Department of Physical Therapy
 Rosalind Franklin University of Medicine & Science
 North Chicago, IL 60064 Mary K. Hastings, PT, DPT, MSCI, ATC
 Associate Professor, Program in Physical Therapy and Department of Orthopaedics
 Washington University School of Medicine
 St. Louis MO 63108 Smita Rao PT, PhD Associate Professor, Department of Physical Therapy New York University New York, NY 10010 Christopher G. Neville, PT, PhD Associate Professor, Department of PT Education Upstate Medical University Syracuse, NY 13210 Ruth L. Chimenti, PT, DPT, PhD Postdoctoral Fellow, Department of Biomedical Engineering University of Rochester Rochester, NY 14627 The authors have no affiliations with any organization/ entity with a financial or non-financial interest in the material presented

Course Learning Objectives:

1. Review current evidence on normal midfoot kinematics and kinetics that occur during daily activities

2. Recognize the signs of failure of key muscles and/or ligaments that are needed to support the midfoot

3. Identify the key predictors of a disruption in medial column alignment and foot function

4. Identify the different potential effects of external supports on changing midfoot mechanics

5. Recognize limitations of weight-bearing clinical tests when midfoot function is impaired

Review of Normal Midfoot Function Frank DiLiberto PT, PhD, OCS, FAAOMPT Assistant Professor, Department of Physical Therapy
 Rosalind Franklin University of Medicine & Science How is midfoot function studied? In-vivo Surface Markers Some concern with directly tracking all of the midfoot bones (Nester et al., 2007b) Three (or more) segment modeling

Tibia Rearfoot (calcaneus/talus) Forefoot (metatarsals)

Multi-segment Biomechanics Rearfoot to Tibia Motion and Power Multi-segment Biomechanics

Forefoot to Rearfoot Motion and Power Allows for inference of midfoot biomechanics

We Will Review…..

Kinematics during walking Forefoot with respect to Rearfoot (ROM°)

Kinetics during walking and stair ascent

Midfoot peak power Study Design & Sample

Observational Cohort Study

Kinematic and Kinetic Foot Model Kinematic Model

5 Segments: Tibia, calcaneus, metatarsals (1st, 3rd and 5th) Angular displacement (ROM)

Forefoot with respect to Rearfoot Kinetic Model

3 Segments: Forefoot, Rearfoot, Tibia Midfoot Power

Rate of torque production Results: Sagittal Plane Kinematics
(DF / PF ROM°) Transverse Plane Kinematics
(ADD / ABD ROM°) Midfoot Power Across Activity Review and Summary

Muscle performance at the midfoot contributes power for push off Increases with increases in demand of activity

For normal midfoot function we need….

Extensibility and strength of non-contractile tissues (Jennings et al., 2008; Carvaggi et al., 2010)

Joint capsules, ligaments, tendons

Mobility of joint surfaces (Blackwood et al., 2005; Nester et al., 2007a; Okita et al., 2014)

Tarsal and tarsometatarsal joints

Muscle performance (Nikki et al., 2001; Kelly et al., 2014; Kelly et al., 2015)

Intrinsic and extrinsic muscles What happens when mechanisms behind midfoot function are compromised?

What can we do about it? References Nester C, Liu AM, Ward E, Howard D, Cocheba D, Derrick T, et al. In vitro study of foot kinematics using a dynamic walking cadaver model. Journal of Biomechanics 2007;40:1927–1937 Nester C, Jones RK, Liu A, Howard D, Lundberg A, Arndt A, et al. Foot kinematics during walking measured using bone and surface mounted markers. Journal of Biomechanics. 2007;40:3412-23. DiLiberto FE, Tome J, Baumhauer JF, Quinn JR, Houck J, Nawoczenski DA. Multi-joint foot kinetics during walking in people with Diabetes Mellitus and peripheral neuropathy. Journal ofBiomechanics. 2015; 48:3679–3684. Tome J, Nawoczenski DA, Flemister S, Houck J. Comparison of foot kinematics between subjects with posterior tibialis tendon dysfunction and healthy controls. Journal of Orthopaedic and Sports Physical Therapy. 2006;36:635-44. Dixon PC, Bohm H, Doderlein L. Ankle and midfoot kinetics during normal gait: A multi-segment approach. Journal of Biomechanics. 2012;45:1011-6. Jennings MM, Christensen JC. The Effects of Sectioning the Spring Ligament on Rearfoot Stability and Posterior Tibial Tendon Efficiency. The Journal of Foot and Ankle Surgery. 2008;47:219-24. Caravaggi P, Pataky T, Gunther M, Savage R, Crompton R. Dynamics of longitudinal arch support in relation to walking speed: contribution of the plantar aponeurosis. Journal of Anatomy. 2010;217:254-61. Blackwood CB, Yuen TJ, Sangeorzan BJ, Ledoux WR. The Midtarsal Joint Locking Mechanism. Foot & Ankle International. 2005;26:1074-80 Okita N, Meyers SA, Challis JH, Sharkey NA. Midtarsal joint locking: New perspectives on an old paradigm. Journal of Orthopaedic Research. 2014;32:110-5. Niki H, Ching RP, Kiser P, Sangeorzan BJ. The effect of posterior tibial tendon dysfunction on hindfoot kinematics. Foot & Ankle International. 2001;22:292-300. Kelly LA, Cresswell AG, Racinais S, Whiteley R, Lichtwark G. Intrinsic foot muscles have the capacity to control deformation of the longitudinal arch. Journal of the Royal Society Interface. 2014;11:1-9. Kelly LA LG, Cresswell AG. Active regulation of longitudinal arch compression and recoil during walking and running. Journal of the Royal Society Interface. 2015;12.

How Diabetes Mellitus affects multi-segment foot motion and midfoot power

Frank DiLiberto PT, PhD, OCS, FAAOMPT Assistant Professor Department of Physical Therapy Rosalind Franklin University of Medicine & Science Diabetes Mellitus Poor Blood Glucose Control Peripheral Neuropathy Reduced or Variable Activity Elevated Plantar Pressure

Peripheral Neuropathy and Foot Biomechanics

Peripheral neuropathy Decreases tissue extensibility Decreased functional ROM Atrophied and fatty muscles Decreased muscle performance …Deformity

Purpose: In people with Diabetes and Peripheral Neuropathy….

Assess individual metatarsal and forefoot ROM during terminal stance

Assess ankle and midfoot muscle performance Power (Rate of torque production)

Relate midfoot power to plantar pressure

Study Design & Sample

Case (DMPN) – Control (MC) DMPN group without history of ulceration

Kinematic and Kinetic Foot Model Kinematic Model 5 Segments: Tibia, calcaneus, metatarsals (1st, 3rd and 5th) Angular displacement and velocity

Forefoot and metatarsals Kinetic Model 3 Segments: Forefoot, Rearfoot, Tibia Power and Total Power: Rearfoot and Midfoot

Kinetic Measurements

Power Negative = power absorption eccentric muscle activity Positive = power generation concentric muscle activity

Pressure Measurements Forefoot mask (55-80%)

Pressure Time Integral Peak pressure across time

Results – Sagittal Plane Kinematics
 (Total DF / PF ROM°) Transverse Plane Kinematics
(Total Abd / Add ROM°) Rearfoot Power Midfoot Power Negative Total Power Ratio Pressure and Power

Discussion

People with DMPN without deformity or ulceration history

Limited ROM at multiple metatarsals Likely related to tissue extensibility and muscle control

Abnormal power profile at both the RF and MF Likely related to muscle contractility and activation

Abnormal power profile at both the RF and MF Decreased + power Impaired concentric contraction Excessive – power Poor eccentric control Increased – TP Ratio Increased loading on MF passive structures ….Deformity? Increased forefoot pressure ….Tissue Breakdown?

Future Research DM vs. DMPN vs. DMPN + ulcer history Evaluate:

Decline of kinetic function MF negative total power

Determine the appropriate time point for clinical intervention….

What structures and mechanisms should we be targeting?

Acknowledgements Jill Quinn RN, PhD Din Chen PhD Jeff Houck PT, PhD Josh Tome, MS Judy Baumhauer MD, MPH Deborah Nawoczenski PT, PhD University of Rochester Medical Center - Strong Health Network

Orthopaedic Foot and Ankle Institute Highland Family Medicine and Diabetes Health Source Rochester Internal Medicine Associates

University of Rochester School of Nursing and Department of Orthopaedics

Funding Source

University of Rochester, School of Nursing Dean’s Fellowship University of Rochester, Department of Orthopaedics, Louis A.

Goldstein Award

Predictors of Midfoot Deformity in People with Diabetes Mellitus

Mary Hastings, PT, DPT, MSCI, ATC

Associate Professor Washington University in St. Louis, MO

Program in Physical Therapy Funding Sources • National Institutes of Health:

• K12 HD055931: Comprehensive Opportunities for Rehabilitation Research and Training

• KL2 TR000450 and UL1 TR000448: Postdoctoral Program • Washington University Program in Physical Therapy, St. Louis,

MO USA

Prevalence of Diabetes

Foot Deformity Cascade

Medial Column Deformity in Diabetes • Thought to be

• Confined to a Charcot event • Driven by bone deterioration • Once treated stable over time

• However • Medial column deformity progressed over time • Indication of progression in uninvolved foot too

Factors that Impact Medial Column Alignment and Function

• Intrinsic Foot Muscle • Plantar fascia • Extrinsic foot muscle/tendon

Participant Characteristics • DMPN (DMPN, n=23)

• Diabetes mellitus • Peripheral neuropathy

• unable to feel 5.07 Semmes-Weinstein monofilament on at least one plantar location

• Spectrum of medial column foot alignment

• Controls (n=12) • No Diabetes or peripheral neuropathy • No medial column foot deformity • Age and weight matched

Purpose • To determine the ability of measures of foot and leg muscle, tendon,

fascial integrity and function to predict • Medial column alignment and Medial column function…

Methods: Medial Column Function • Plantarflexion excursion of the forefoot relative to the hindfoot

• Kinematics of the single-limb heel rise • Segments

• Hindfoot • Forefoot

• 4 sets of 5 reps • Averaged 3 with highest plantarflexor torque

Methods: Intrinsic Foot Muscle • Magnetic Resonance Images

• Intrinsic foot muscle and fat • Total volumes from talonavicular to tarsometatarsal

(Cheuy 2013a, Cheuy 2013b) • MR specifics

• Transverse • 0.36 mm x 0.36 mm x 3.5 mm, no inter-slice gap • T1 weighted • Pulse repetition time=5360 msec • Echo Time=38 msec • Image Matrix 384 x 384

Methods: Plantar Fascia Function Change in Meary’s Angle

• Toe flat to toe extended position-60° (Hastings 2011, Gelber 2014)

Methods: Extrinsic Foot Muscle/Tendon • MRI: Tendon volumes

• Posterior tibialis • Flexor digitorum longus • Ratio: Posterior Tibialis/Flexor digitorum longus • Total: 9 slices proximal to talocrural joint

• MR specifics • Transverse • 0.36 mm x 0.36 mm x 3.5 mm, no inter-slice gap • T1 weighted • Pulse repetition time=5050 msec, Echo Time=38 msec • Image Matrix 256 x 256

Methods: Extrinsic Foot Muscle/Tendon • Plantarflexor Torque

• Biodex • 60°/sec • Warm up

• 3 trials • Average 2 highest trials

Data Analysis: • Group Differences

• Chi-square • T-test

• Correlations • Predictor variables for model

• Multiple Regression • Predicting

• Foot alignment-Meary’s • Foot function-Forefoot relative to hindfoot plantarflexion excursion

Results: Demographics • Participants

• Around 60 yo, more male than female, and obese class II

Results: Variables to be Predicted • Meary’s Angle

• Large range of angles • Forefoot on hindfoot plantarflexion excursion

• DMPN group has limited ability to plantarflex the forefoot on the hindfoot

Results: Intrinsic Foot Volumes • DMPN have decreased muscle volume and increased fat

compared to controls

Results: Tendon and Fascial Volumes • No difference in tendon or plantar fascia volume between

those with DMPN and controls

Results: Plantarflexor Torque (Nm) • DMPN have reduced plantarflexor torque

Alignment Predictors in DMPN • Meary’s Predictors

• Ratio Posterior tibialis/Flexor digitorum longus Tendon Volume (18%) • Intrinsic muscle volume (16%) • Total variance explained=44%

Function Predictors in DMPN • Forefoot on hindfoot excursion predictors

• Plantarflexor Peak Torque (24%) • Intrinsic Fat Volume (19%) • Total variance explained=44%

• Plantar fascia function • correlation with function (r=.34) • Not a significant predictor

Conclusions • DMPN

• Leg and foot muscle/tendon function deterioration • Muscle and tendon deterioration associated with

• Deformity • Function

Limitations…leading to future research • Small sample size for a big question • Cross sectional study for a longitudinal/progressive question • Incomplete model: bone shape, ligament integrity • Can neuropathic muscle be strengthened?

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Midfoot Arthritis:
 Impairments to Intervention Smita Rao, PT, PhD Associate Professor Department of Physical Therapy New York University Background

• Arthritis: One of the leading causes of disability (MWWR, 2006) • Midfoot Arthritis: High potential for chronic secondary disability

Incidence and Prevalence • Athletic population • Minor twisting injuries • Motor vehicle trauma • Chronic overload – high heels Operative Management

• Surgical management - challenging • Complications following surgery

• Non-union, broken screws and wound problems • May necessitate further surgery involving revision, arthrodesis,

hardware removal .

Non-operative Management • Primary aim of Treatment

- Provide pain relief • Steel shanked shoes

• Poor compliance • Custom-molded three- quarter insert (3Q)

• Most common recommendation • Patients continue to report pain Alternative

Purpose • Assess impairments contributing to symptoms

• Segmental foot motion • Regional loading

• Assess the effect of 4 week intervention using the FL on symptoms

• Segmental foot motion • Regional loading

Subjects

• Clinical: • Pain on dorsum, localized to TMT region • Aggravated by walking • Stair descent

• Radiographic: • Joint space reduction • Osteophytes • ‘Dorsal bossing’

Functional Outcomes

• Foot Function Index – Revised (FFI-R) • Pain • Stiffness • Disability • Activity Limitation • Psychosocial Issues (Budiman-Mak, E et al, 2006)

• Psychometric properties • Reliability, Convergent validity, Criterion validity • Responsiveness (SooHoo et al. 2006, Budiman-Mak, E et al, 2006)

Results: Foot Function Index – Revised (Rao et al. J Biomech 2009)

Kinematics: Data Acquisition • 5 segment kinematic foot model. • Sensors placed over respective segments • Secured with skin tape • Anatomically based local co-ordinate systems for each segment • Reference trial: Subtalar Neutral (Tome et al. 2004, Houck et al. 2008) Kinematics: Results New Insights:
 Group x Activity Interaction • 1st metatarsal plantarflexion ROM (p = 0.02) • Calcaneal eversion ROM (p < 0.01) • At baseline, patients with MFA show a stiffening strategy. • Instability, evident only in high demand activities. Plantar Loading: Data acquisition

• Data Acquisition • Barefoot • EMEDTM

• Data Analysis • 6 “masks” • Heel, Medial and Lateral Midfoot, Medial and Lateral Forefoot, Great

Toe • Dependent Variables: Average Pressure - mean of the highest pressures

sustained within each mask and expressed in kilopascals (kPa).

Plantar Loading: Results New Insights: 
 Cluster Analysis – Adequacy Index 
 and Bivariate Scatter plot • K-means clustering identified two subgroups:

• Cluster 1 (higher medial midfoot average pressure (n=20)) • Cluster 2 (lower medial midfoot average (n=10))

Conclusions: • Independently or in combination, these patterns of loading and motion may

contribute to articular stress and thus provoke symptoms. Mechanisms underlying Pain Relief Results – Baseline to 4 weeks

Significant symptomatic improvement after 4 week intervention with the FL (Rao et al, APMR 2009) Kinematic results: FL compared to Shoe In Shoe Plantar Loading Changes Decreased midfoot loading with FL, compared to 3Q. No difference between FL and shoe. (Rao S. et al., J Orthop Sports Phys Ther 2009) Mechanisms underlying Symptomatic Relief • Accompanied by decreased 1st MTP ROM (compared to shoe), decreased

medial midfoot loading, (compared to 3Q) (Rao S, et al. Arch Phys Med Rehab, 2010)

Limitations and Caveats • Larger sample sizes, longer term follow-up and clinical trial design indicated

• Homogenous sample = interesting, in and of itself, but may not be

generalizeable to men (different BMI range) and activity demands.

Current Interests: • Cumulative Stress in Individuals with Foot Pain

(Rao et al Arthritis Care and Research (accepted)) • Pain mechanisms in Individuals with Foot Pain

• Widespread mechanical hyperalgesia • Efficacy of soft tissue mobilization

• Reduction of hyperalgesia • Restoration of plantar load distribution and muscle activation during walking

Acknowledgements

Rheumatology Research Foundation AOFAS Research Grant Arthritis Foundation Chapter Grant and Post-doctoral Fellowship Deborah A Nawoczenski, PT, PhD Judith F Baumhauer, MD, MPH Jeff Houck, PT, PhD Josh Tome, MS Howard Hillstrom, PhD Kenneth Mroczek, MD

Loss of dynamic midfoot support from Tibialis Posterior Tendon Dysfunction: Biomechanical effects and treatment options

Christopher Neville, PT, PhD Associate Professor Upstate Medical University Physical Therapy Education Syracuse, NY 13210 [email protected] Midfoot Support…

Tibialis Posterior Tendinopathy Role of Tibialis Posterior Spring Ligament and Sagittal Plane Collapse

• Correction of flatfoot deformity unloads soft tissue structures (spring ligament)

Flatfoot Deformity Walking Flatfoot Deformity during Heel rise Tibialis Posterior Tendinopathy Clinical Strength Measure Lower Arch EMG: • Self-Adhesive (Ag/AgCl) electrodes were placed on the skin overlying the

belly of the PL • Indwelling fine-wire electrode were placed into the TP muscle under

ultrasound guidance • Stimulation (Grass - square pulse stimulator) with intensities to produce a

strong contraction

Purpose

To determine the effect of a longer foot plate design and ankle articulation on foot kinematics and ankle power in subjects with stage II PTTD.

Methods:

Sample Kinematic Model Ankle Kinetics

Analysis:

• Repeated Measures ANOVA Model

• Condition (5 levels) • Off-the-shelf • Custom standard • Custom articulated • Custom extended • Shoe Only

• Phase (4 levels) • LR, MS, TS, PS

• Model repeated for each DV (MLA, FF Abd/ Add, HF Ev/Inv, Ankle Power)

Results…

Frontal Plane Hindfoot Motion

Ankle Power

Discussion…. Summary Kinematics • Custom Devices are achieving control of flatfoot deformity with:

• hindfoot inversion • ankle articulation design – may facilitate muscle control

• forefoot plantarflexion (raising MLA) • forefoot adduction (standard design and extended design with

extended showing promise of greater control) • Does correction of flatfoot kinematics relate to improved function? Summary Kinetics • Articulated Ankle Design

• Preserves Push-off power at the end of stance • Solid Ankle Design

• Limits ankle power with no greater control of kinematics

Impact of midfoot motion on clinical tests: Single limb heel rise & Lunge test

Ruth Chimenti, DPT, PhD Postdoctoral Fellow University of Iowa Department of Physical Therapy & Rehabilitation Science Why the midfoot?

• Clinical tests of rearfoot strength (e.g. single limb heel rise) and flexibility (e.g. lunge test)

• Impact of midfoot… – How can “rearfoot clinical tests” be used to assess midfoot

function?

– How could the midfoot mask and/or exacerbate clinical findings at the rearfoot?

– How would midfoot pathology alter your treatment strategy? Current use of Heel Rise Test

Assess plantar flexor strength and endurance

Part of diagnostic criteria for establishing stage of posterior tibial tendon dysfunction (PTTD) (Johnson & Strom, 1989; Gluck, Heckman, Parekh, 2010)

Purpose

Examine kinematics of a unilateral heel rise between: • Stage II PTTD • Older Controls • Younger Controls

Hypotheses

• People with PTTD compared to controls (young and old) will demonstrate:

↓ Heel rise height ↓ Ankle plantar flexion ↓ 1st Metatarsal plantar flexion ↓ Rearfoot inversion

Participants Laboratory Performance Measures Normalized Heel Height

Change in vertical position of calcaneal marker as a % of truncated foot length

Forefoot

1st Met PF with relation to the Calcaneus Rearfoot

Calcaneal PF with relation to the tibia Calcaneal INV with relation to the tibia Heel Rise Height

• Significant differences in heel rise height between all groups Forefoot and Rearfoot ROM Clinical Implications for Rearfoot

• Single limb heel rise performance (height, forefoot & rearfoot excursions) is affected by age and PTTD

Heel Rise Height

• PTTD = 7.7 ± 1.9 cm • Old = 10.5 ± 1.6 cm • Young = 12.0 ± 1.6 cm

Clinical Implications for Midfoot

• Successful performance of the single limb heel rise depends on forefoot and rearfoot excursion

• Restore medial column and rearfoot plantar flexion during functional tasks, e.g. walking and stair climbing

• Patients with PTTD have the potential to raise the medial longitudinal arch under lower load

• 50% achieved 1st metatarsal PF during bilateral heel rise (Houck, Neville, Tome, Flemister, 2009)

• 30% achieved 1st metatarsal PF during unilateral heel rise Lunge test in patients with insertional achilles tendinopathy Current use of the Lunge test

• Limited ankle dorsiflexion commonly targeted in rehabilitation

• Advantages of the lunge test: – Weight-bearing test indicative of function – Time efficient – Minimal equipment – Reliable (Bennell et al, 1998; Chisholm et al, 2012;

Jones, 2005; Munteanu et al, 2009)

• Limitations of the lunge test: – Assumes foot is a rigid structure

• Calcaneal plantar flexion (Chizewski & Chiu, 2012) • Lowering of medial longitudinal arch (Jung et al, 2009)

– May be less valid for persons with foot pathology

• Insertional achilles tendinopathy (IAT) – 5% of general population has had achilles tendinopathy (Kujala,

Sarna, & Kaprio, 2005)

– 1/3 cases at insertion (Karjalainen et al, 1999)

• Lunge used for – Assessment of DF (lunge test) – Intervention (weight-bearing calf stretch)

• Unknown – Contributions of forefoot vs rearfoot – Effect of rearfoot pathology

Purposes

• Compare single-segment (representing a clinical lunge test measure) versus multi-segment contributions to lunge test dorsiflexion

• Determine if differences are present in patients with chronic insertional achilles tendinopathy

Participants Methods Results Discussion

– Lunge test represents: • Rearfoot DF (Single-segment model ~5°>than calcaneal DF) • Rearfoot eversion Consider medial rearfoot posting • 1st metatarsal DF

– IAT group had limited DF compared to controls • Impairment detected by single-segment and multi-segment

models

• Midfoot motion strongly correlated with single-segment DF in IAT

– For examination and interventions support arch/medial side of foot

Why the midfoot?

Midfoot function is needed for rearfoot function Weakness with single limb heel rise may be exaggerated Limited ankle dorsiflexion with lunge test may be masked

Single limb heel rise and lunge position can load (strengthen or stretch) the plantar flexors

But may also be overload the midfoot and passive support structures

Acknowledgements • University of Rochester Medical Center

– Jeff Houck, PT, PhD – Debbie Nawoczenski, PT, PhD – A. Samuel Flemister, MD – Sproull Fellowship

• Faculty and students at Ithaca College – Josh Tome, MS – Annmarie Forenza, DPT – Elizabeth Previte, DPT – Cody Hillin, MS, MD – Amy Smith, PT – Caitlin Pautz, PT

• Funding from Foundation for Physical Therapy

References Bennell KL, Talbot RC, Wajswelner H, Techovanich W, Kelly DH, Hall AJ. Intra-rater and inter-rater reliability of a weight-bearing lunge measure of ankle dorsiflexion. Australian journal of physiotherapy. 1998;44:175-80. Chisholm MD, Birmingham TB, Brown J, Macdermid J, Chesworth BM. Reliability and validity of a weight-bearing measure of ankle dorsiflexion range of motion. Physiother Can. 2012;64:347-55. Chizewski MG, Chiu LZ. Contribution of calcaneal and leg segment rotations to ankle joint dorsiflexion in a weight-bearing task. Gait Posture. 2012;36:85-9. Gluck GS, Heckman DS, Parekh SG. Tendon Disorders of the Foot and Ankle, Part 3: The Posterior Tibial Tendon. Am J Sports Med. 2010; 38:2133-2144. Houck J, Neville C, Tome J, Flemister A. Foot kinematics during a bilateral heel rise test in participants with stage II posterior tibial tendon dysfunction. J Orthop Sports Phys Ther. 2009; 39(8): 593-603. Johnson KA, Strom DE. Tibialis posterior tendon dysfunction. Clin Orthop Relat Res. 1989; 239:196-166. Karjalainen, P.T., et al., MR imaging of overuse injuries of the Achilles tendon. AJR.American journal of roentgenology, 2000. 175(1): p. 251-260. Kujala, U.M., S. Sarna, and J. Kaprio, Cumulative incidence of achilles tendon rupture and tendinopathy in male former elite athletes. Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine, 2005. 15(3): p. 133-135. Kulig K, Popovich JM, Noceti-Dewit LM, Reischl SF, Kim D. Women with posterior tibial tendon dysfunction have diminished ankle and hip muscle performance. J Orthop Sports Phys Ther;. 2011; 41(9):687-694). Munteanu SE, Strawhorn AB, Landorf KB, Bird AR, Murley GS. A weightbearing technique for the measurement of ankle joint dorsiflexion with the knee extended is reliable. Journal of science and medicine in sport / Sports Medicine Australia. 2009;12:54-9.

Clinical Implications

Examination

Deformity assessment: • Clinical measures of alignment

• Navicular height • medial longitudinal arch angle …well correlated with radiographic measures

Foot and calf muscle function • Single limb heel rise

Ankle and midfoot range of motion • Lunge test

Interventions for active structures Intrinsic muscles Extrinsic muscles

Interventions for passive structures

Orthotics Bracing

Panel discussion

Challenges/ Opportunities