Intra- and interobserver reliability of quantitative ultrasound measurement of the plantar fascia

Sonographic and clinical effects of manual physical therapy for plantar fasciitis: randomized prospective controlled trial

OBJECTIVE

This study aimed to evaluate the efficacy of manual physiotherapy on clinical outcomes, morphology of plantar fascia (PF), thicknesses of calcaneal fat pad (CFP) and Kager's fat pad (KFP) with ultrasound imaging in plantar fasciitis (PFS) patients. Also, to evaluate the PF thickness, pain and foot functional outcomes among PFS phases.

METHODS

A randomized controlled trial was conducted on 122 subjects divided into three groups: group A (40 patients with PFS) underwent manual physiotherapy, group B (42 patients with PFS) without any intervention and group C (40 healthy subjects) were matched by age, gender and BMI with each patient in group A and B. The following outcomes were evaluated at baseline and one-month of follow-ups: morphology of PF and thicknesses of CFP and KFP, pain, foot functional limitation.

RESULTS

PF thickness was significantly thickened in group A and B compared to group C (P < 0.001). A significant decrease in incidence of PF echogenicity and CFP thickness were found in group A and B compared to group C. Moreover, significant improvement was observed in PF thickness (P < 0.001), PF echogenicity (P < 0.001) and CFP thickness (P = 0.002) in group A at one-month after the treatment. Furthermore, pain intensity and foot functional limitation was significantly improved within group A after receiving the treatment. Significant improvement was noted in PF thickness, pain intensity and foot functional limitation among patients with acute phase.

CONCLUSION

The manual physiotherapy is effective in treatment of PF thickening, hypoechogenicity, pain intensity and activity limitations, particularly in patients associated with acute PFS.

Ultrasound Strain Elastography Reliability in the Assessment of the Plantar Fascia and Its Relationship with the Plantar Thickness in Healthy Adults: An Intra and Interobserver Reliability Study in Novice Evaluators

PURPOSE

This study was aimed at verifying both the intraobserver and interobserver reliability of measuring plantar fascia stiffness for a given image in healthy active adults.

METHODOLOGY

This study is reported following the Guidelines of Reporting Reliability and Agreement Studies. A total of 20 plantar fascia from healthy volunteers were analyzed. The thickness of the plantar fascia was measured vertically from the anterior edge of the inferior calcaneal border to the inferior border of the plantar fascia and the ultrasound elastography measurement was taken at the calcaneal insertion of the plantar fascia with the region of interest one centimeter away from the insertion.

RESULTS

The ultrasound strain elastography measurements: the right intraobserver 1 showed an ICC value of 0.9 and the left intraobserver 1 showed an ICC value of 0.78, while the right intraobserver 2 showed an ICC value of 0.91 and the left intraobserver 2 showed an ICC value of 0.83. Interobserver measurements showed excellent reliability with a right ICC value of 0.8 and a left ICC value of 0.9 for the plantar fascia thickness measurements.

DISCUSSION

The results of this study showed a strong correlation between left and right plantar fascia thickness. The intraobserver reliability was excellent for both plantar fascia ultrasound strain elastography and thickness measurements, with interobserver measurements showing excellent reliability.

The effects of a custom foot orthosis on dynamic plantar pressure in patients with chronic plantar fasciitis: A randomized controlled trial

BACKGROUND

Plantar fasciitis is one of the most common causes of heel pain. The plantar fascia supports the longitudinal arch and absorbs ground reaction forces during the static and dynamic phase(s) of weight-bearing. The purpose of this randomized controlled trial study was to determine the effects of CAD/CAM foot orthoses that were designed based on the dynamic plantar pressure in patients with plantar fasciitis.

METHODS

This study was performed on 34 patients with plantar fasciitis. Outcomes were compared based on plantar fascia thickness; peak pressure, mean pressure, and maximum force; and pain, activity of daily living, quality of life, and sports activity that were evaluated by ultrasound, plantar pressure platform, and the Foot and Ankle Outcome Score, respectively. The patients were randomly assigned into two groups: the experimental group (CAD/CAM orthoses and night splint) and the control group (night splint only). All data were recorded again after 4 weeks.

RESULTS

Pain ( P = 0.002) and plantar fascia thickness ( P = 0.001) decreased significantly after 1 month of intervention. Activity of daily living ( P = 0.044) and quality of life ( P = 0.001) showed a significant increase. There was a trend in increasing peak pressure in all masking regions in both groups. The maximum force remarkably reduced in the experimental group in all regions.

CONCLUSIONS

The results demonstrated that CAD/CAM foot orthoses designed based on dynamic plantar pressure with night splint can reduce the plantar fascia thickness and pain associated with plantar fasciitis and increase the activity of daily living, quality of life, and sports activity.

Effects of customized insoles with medial wedges on lower extremity kinematics and ultrasonographic findings in plantar fasciitis persons

The customized insole is widely recommended as an effective intervention for pain reduction and foot function improvement in plantar fasciitis persons. However, it is unclear whether the additional correction of medial wedges could change the kinematics from the only insole. The objectives of this study were thus to compare customized insoles with and without medial wedges on lower extremity kinematics during gait and to determine the short-term effects of the customized insole with medial wedges on pain intensity, foot function, and ultrasonographic findings in plantar fasciitis persons. A within-subject, randomized, crossover design within motion analysis research laboratory was conducted among 35 persons with plantar fasciitis. Main outcome measures included joint motions of the lower extremity and multi-segment foot, pain intensity, foot function, and ultrasonographic findings. The customized insole with medial wedges produced less knee motion in the transverse plane and hallux motion in all planes during the propulsive phase than that without medial wedges (all p < 0.05). After the 3-month follow-up, the insoles with medial wedges decreased pain intensity and increased foot function. Abnormal ultrasonographic findings also decreased significantly after the 3-month treatment of insoles with medial wedges. Customized insoles with medial wedges seem superior to those without medial wedges on both multi-segment foot motion and knee motion during propulsion. Positive outcomes from this study supported the use of customized insoles with medial wedges as an effective conservative treatment in patients with plantar fasciitis.Trial registration: TCTR20210928006 (28/09/2021).

Foot kinematics in runners with plantar heel pain during running gait

BACKGROUND

Plantar heel pain associated with plantar fascia pathology (PHP) is one of the most common running overuse injuries. Degeneration and changes in the mechanical properties of the plantar fascia associated with PHP can result in changes in foot kinematics during gait.

RESEARCH QUESTION

How do running gait foot kinematics differ between female and male runners with and without PHP?

METHODS

Retrospective study of 13 runners with PHP (7 female, 6 male) and a matched group of 13 uninjured runners (6 female, 7 male). A seven-segment foot model was used to quantify six functional articulations (rearfoot complex, lateral and medial midfoot, lateral and medial forefoot, and first metatarsophalangeal). Functional articulation ROM during early, mid, and propulsion running stance subphases was assessed. Two-way ANOVAs and Friedman's two-way ANOVA for ranks tests were conducted for normally distributed variables and non-normally distributed variables, respectively.

RESULTS

During early stance, PHP runners demonstrated significantly increased lateral midfoot eversion ROM compared to uninjured runners. During the propulsion phase, male runners with PHP demonstrated increased medial midfoot eversion and dorsiflexion ROM and increased medial forefoot plantar flexion compared to uninjured male runners. Also during propulsion, females with PHP went through significantly less medial forefoot plantar flexion ROM compared to uninjured female runners.

SIGNIFICANCE

Given the function of the plantar fascia to assist foot supination, the differences in runners with PHP, which were consistent with increased pronation or inadequate supination, may be the result of insufficient tension during the stance phase of running gait caused by degeneration of the plantar fascia. Further, the significant medial midfoot and medial forefoot group by sex interactions during propulsion suggest that PHP may affect male and female runners differently. Understanding the effect of PHP on foot function during running may aid in the development of future rehabilitation programs and/or treatment outcome assessments.

Effects of dry needling and stretching exercise versus stretching exercise only on pain intensity, function, and sonographic characteristics of plantar fascia in the subjects with plantar fasciitis: a parallel single-blinded randomized controlled trial

OBJECTIVES

Plantar fasciitis is a common problem in the foot region which has negative considerable impact on foot function.

METHODS

In this parallel blinded randomized controlled trial, a total of thirty-seven subjects with plantar fasciitis (forty feet) were enrolled randomly to either the control group (stretching exercise) or the experimental group (stretching exercise plus dry needling). All interventions lasted six weeks and both groups were followed for two weeks. Primary outcomes were first step pain, pain, and activity daily function subscales of the FAOS questionnaire and secondary outcomes were plantar fascia thickness, and echogenicity.

RESULTS

The mixed model ANOVAs showed significant group × time interactions for all primary outcomes. In both groups, first step pain and both subscales of the FAOS questionnaire were improved compared to baseline measurements. There were considerable differences between the two groups and the experimental group experienced more improvements in primary outcomes compared to the control group. For secondary outcomes, plantar fascia thickness at insertion significantly decreased, and the echogenicity in the two regions significantly increased in the experimental group compared to the control group.

CONCLUSION

These results suggest that the combination of dry needling and stretching exercises can be an effective conservative treatment for plantar fasciitis subjects.

A Pilot Study on the Reliability of Ultrasound-Based Assessment of Patella Diameter and Sulcus Angle

This pilot study aimed to determine the reliability of a newly developed ultrasound-based protocol for the assessment of patella diameter and sulcus angle. The diameter of the patella expressed in mm and the sulcus angle, expressed in degrees were measured in the right knee in 12 healthy participants (eight women and four men) in two separate sessions by two examiners (experienced rater and inexperienced rater) using ultrasonography according to a developed standardized protocol. The reliability was determined on the calculated intraclass correlation coefficient, ICC, expressed as a 95% confidence interval (lower bound, upper bound). For the patella diameter measurement, intra-rater and inter-rater reliability were good to excellent, with the ICC exceeding 0.836-0.998 and 0.859-0.997, respectively. The intra-rater and inter-rater reliability of the sulcus measurement was moderate to excellent, as the ICC amounted to 0.559-0.993 and 0.559-0.990, respectively. The reliability of both measures increased with the experience of the examiner. Therefore, it was determined that the newly developed protocol for an ultrasound-based assessment of patella diameter and sulcus angle is reliable. Further studies validating their clinical use should be carried out.

Variations in the Thickness of the Plantar Fascia After Training Based in Training Race. A Pilot Study

Plantar fascia (PF) is a connective tissue made up of mostly type 1 collagen that is subjected to constant loads. This study evaluated the effect of continuous running on tissue stress in the PF by measuring changes in the thickness of the PF using ultrasound scans. It was a cross-sectional study involving 24 runners from the University of Valencia, recruited as volunteers between December 2018 and February 2019. A variety of data was recorded: (age, body mass index, type of footwear, number of workouts per week, KM run per week, sports injuries in the last year, pre and postrace ultrasound PF measurements). There were significant differences in the 3 postrace measurements of the left foot (<0.001). PF thicknesses were measured before and after running, with a minimal average difference of 0.4 mm in the medial and central fascicles, and 0.3 mm in the lateral fascicle. We observed PF thicknesses above 4mm in asymptomatic patients with no signs of vascularisation, proving that increased PF thickness is not the only criterion for diagnosis of plantar fasciitis.

Surgical or non-surgical treatment of plantar fasciopathy (SOFT): study protocol for a randomized controlled trial

Background

Plantar fasciopathy is the most common reason for complaints of plantar heel pain and one of the most prevalent musculoskeletal conditions with a reported lifetime incidence of 10%. The condition is normally considered self-limiting with persistent symptoms that often last for several months or years. Multiple treatments are available, but no single treatment appears superior to the others. Heavy-slow resistance training and radiofrequency microtenotomy for the treatment of plantar fasciopathy have shown potentially positive effects on short- and long-term outcomes (> 3 months). However, the effect of heavy-slow resistance training compared with a radiofrequency microtenotomy treatment is currently unknown. This trial compares the efficacy of heavy-slow resistance training and radiofrequency microtenotomy treatment with supplemental standardized patient education and heel inserts in improving the Foot Health Status Questionnaire pain score after 6 months in patients with plantar fasciopathy.

Methods

In this randomized superiority trial, we will recruit 70 patients with ultrasound-confirmed plantar fasciopathy and randomly allocate them to one of two groups: (1) heavy-slow resistance training, patient education and a heel insert (n = 35), and (2) radiofrequency microtenotomy treatment, patient education and a heel insert (n = 35). All participants will be followed for 1 year, with the 6-month follow-up considered the primary endpoint. The primary outcome is the Foot Health Status Questionnaire pain domain score. Secondary outcomes include the remaining three domains of the Foot Health Status Questionnaire, a Global Perceived Effect scale, the physical activity level, and Patient Acceptable Symptom State, which is the point at which participants feel no further need for treatment.

Discussion

By comparing the two treatment options, we should be able to answer if radiofrequency microtenotomy compared with heavy-slow resistance training is superior in patients with plantar fasciopathy.

Trial registration

ClinicalTrials.gov NCT03854682. Prospectively registered on February 26, 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06785-w.

Clinical And Plantar Fascial Morphologic Changes After Proximal Medial Gastrocnemius Release Treatment of Recalcitrant Plantar Fasciitis

BACKGROUND

Magnetic resonance imaging (MRI) has been used as a diagnostic and prognostic instrument to evaluate the results of conservative treatment for plantar fasciitis. However, there are scarce data available relative to changes in the plantar fascia after operative treatment. The primary objective of this study is to evaluate the imaging changes in patients with recalcitrant plantar fasciitis treated operatively by means of proximal medial gastrocnemius release.

METHODS

Thirteen patients with recalcitrant plantar fasciitis were studied with MRI preoperatively and 1 year after operative treatment. Quantitative (plantar fascia thickness) and qualitative variables (hyperintensity in the plantar fascia, insertional calcaneus bone edema, a plantar fascia tear, and the presence of perifascial collections) were assessed by 2 musculoskeletal radiologists. Clinical results were also measured with American Orthopaedic Ankle & Society (AOFAS), visual analog scale (VAS) pain, and 36-Item Short Form Health Survey (SF-36) scales.

RESULTS

The mean plantar fascia thickness was 6.59 mm preoperatively and 6.37 mm postoperatively (P = .972). No statistically significant differences were found in any of the qualitative variables on comparing the pre- and postoperative periods. Patients reported clinical improvements in pain VAS, AOFAS measurement, and the physical subdomains of the SF-36 scale.

CONCLUSION

Quantitative and qualitative variables assessed for the plantar fascia on MRI did not show any significant change after medial gastrocnemius release despite clear clinical improvement.

LEVEL OF EVIDENCE

Level II, perspective cohort study.

Local hyperalgesia, normal endogenous modulation with pain report beyond its origin: a pilot study prompting further exploration into plantar fasciopathy

Background and aims Persistent tendinopathies were previously considered solely as peripheral conditions affecting the local tendinous tissue until quantitative sensory testing identified involvement of altered pain processing. In similar fashion, pain in patients with persistent plantar fasciopathy may also involve more than local tissue. The aim of this pilot study was to investigate potential differences in conditioned pain modulation and pressure and thermal pain thresholds, between individuals with PF and healthy pain-free controls, as a precursor to a larger-scale study. Methods We assessed 16 individuals with plantar fasciopathy and 11 pain-free controls. Plantar fasciopathy diagnosis was: palpation pain of the medial calcaneal tubercle or the proximal plantar fascia, duration ≥3 months, pain intensity ≥2/10, and ultrasound-measured plantar fascia thickness ≥4 mm. Quantitative sensory tests were performed locally at the plantar heel and remotely on the ipsilateral elbow. Assessments included pain thresholds for pressure, heat and cold, and conditioned pain modulation measured as change in local resting pressure pain threshold with cold water hand immersion. Participants rated pain intensity at pain threshold. Additionally, the area and distribution of plantar fasciopathy pain was drawn on a digital body chart of the lower limbs. Descriptive analyses were performed and between-group differences/effects expressed as standardised mean differences (d). Results There was no conditioned pain modulation difference between participants with plantar fasciopathy and controls (d = 0.1). Largest effects were on local pressure pain threshold and reported pain intensity on pressure pain threshold (d > 1.8) followed by pain intensity for heat and cold pain thresholds (d = 0.3-1.5). According to the digital body chart, pain area extended beyond the plantar heel. Conclusions The unlikelihood of a difference in conditioned pain modulation yet a pain area extending beyond the plantar heel provide a basis for exploring altered pain processing in a larger-scale study. Implications This was the first study to investigate the presence of altered pain processing in individuals with plantar fasciopathy using a conditioned pain modulation paradigm and thermal pain thresholds. We found no indication of an altered pain processing based on these measures, however, patients rated pain higher on thresholds compared to controls which may be important to clinical practice and warrants further exploration in the future.

Reliability in ultrasound measurements of plantar aponeurosis thickness

PURPOSE

Given the increasing research interest in ultrasound plantar aponeurosis (PA) thickness measurements, this study aimed to analyze the inter and intra-rater reliability of independent sonograms and to identify the error related to the image analysis procedure.

METHODS

Twenty-one healthy men participated in this study. Imaging of PA consisted of two independent sonograms per subject. Two raters (R1 and R2) evaluated each sonogram twice using standardized steps. Precision of the image analysis procedure was analyzed using the Bland and Altman plot and Intraclass Correlation Coefficient (ICC). Agreement estimates and ICC were used to assess absolute and relative inter and intra-rater reliability.

RESULTS

Reliability of PA thickness was found to depend strongly on the number of images acquired per subject. Intra-rater agreement for single measurements were 0.696 (R1) and 0.495 (R2), whereas average measurements yielded values of 0.821 (R1) and 0.662 (R2), respectively. Precision within a sonogram varied from ICC values of 0.873 to 0.960 (intra-rater) and 0.670 to 0.822 (inter-rater).

CONCLUSION

Most part of the error in PA thickness measurements seems to be related to the sonogram acquisition process and not to the visual inspection of the image. To minimize error, average values of a minimum of two images per subject should be used. The moderate agreement between raters found in this study ratifies the need of all measurements being made by the same rater or group of raters. If a single rater evaluates all subjects, performing multiple measurements over one image does not seem to affect ICC as much as acquiring multiple images.

Stretching and relaxing the plantar fascia may change plantar fascia thickness but not pressure pain thresholds: a cross-sectional study of patients with plantar fasciopathy

Background

Despite the established relevance of ultrasonography and assessment of pressure pain thresholds in patients with plantar fasciopathy, patient and probe positioning has been mostly ignored and are not necessarily reported in research. The primary aim of this study was to compare plantar fascia thickness in stretched and relaxed positions in patients with plantar fasciopathy. The secondary aim was to compare plantar heel pressure pain thresholds in these positions.

Methods

In this cross-sectional study, we measured the plantar fascia thickness with ultrasonography, and localised pressure pain thresholds using pressure algometry of 20 patients with plantar fasciopathy. These were assessed bilaterally, with the plantar fascia in both a stretched and relaxed position. In the stretched position, toes were maximally dorsiflexed, while in the relaxed position participants’ feet were hanging freely over the end of the table.

Results

The plantar fascia of the most symptomatic foot was significantly thicker when stretched compared with the relaxed position (sagittal: mean difference 0.2 mm, 95%CI: 0.1–0.4, P = 0.013; frontal: mean difference − 0.27, 95%CI: − 0.49 to − 0.06, P = 0.014). The plantar fascia was significantly thinner in the frontal plane compared with the sagittal plane in both positions (stretched: mean difference − 0.2 mm, 95%CI: − 0.42 to − 0.03, P = 0.025; relaxed: mean difference − 0.3 mm, 95%CI:-0.49 to − 0.08, P = 0.008). There was no difference between pressure pain thresholds in stretched or relaxed positions in either foot (P > 0.4).

Conclusions

The plantar fascia was significantly thicker in a stretched compared with a relaxed position and in the sagittal compared with the frontal plane, but differences were smaller than the standard deviation. Pressure pain thresholds were not different between the positions. These results highlight the importance of how ultrasonography is performed and reported in research to allow for replication.

Trial registration

The study was pre-registered September 25th, 2017 on ClinicalTrials.gov (NCT03291665).

Ultrasonography Comparison of the Plantar Fascia and Tibialis Anterior in People With and Without Lateral Ankle Sprain: A Case-Control Study

OBJECTIVE

The purpose of the present study was to evaluate the thickness of the plantar fascia (PF) at the insertion of the calcaneus and the midfoot and forefoot fascial locations, in addition to the thickness of the tibialis anterior, by ultrasound imaging in individuals with and without lateral ankle sprain (LAS).

METHODS

A sample of 44 participants was recruited and divided in 2 groups: 22 feet with a prior diagnosis of grade 1 or 2 LAS (case group) and 22 feet without this condition (healthy group). The thickness and cross-sectional area were evaluated by ultrasound imaging in both groups.

RESULTS

Ultrasound measurements of the PF at the calcaneus, midfoot, and forefoot showed statistically significant differences (P < .05), with a decrease in thickness in the LAS group relative to the healthy group. For the thickness and cross-sectional area of the tibialis anterior, no significant differences (P < .05) were observed between groups.

CONCLUSION

The thickness of the PF at the calcaneus, midfoot, and forefoot is reduced in individuals with LAS relative to the healthy group.

Foot exercise plus education versus wait and see for the treatment of plantar heel pain (FEET trial): a protocol for a feasibility study

Background

Plantar heel pain (PHP) is present in a wide range of individuals and creates significant burden to quality of life and participation in physical activity. The high recurrence rates and persistence of PHP suggests current management options may not address all potentially modifiable factors associated with the condition. Reports of intrinsic foot muscle (IFM) atrophy in individuals with PHP, together with biomechanical evidence of their important contribution to optimal foot function, suggests that an intervention focused on IFM training may be beneficial in managing PHP. We will test the feasibility of a prospective, assessor-blinded, parallel-group, randomised clinical trial that compares foot exercise plus education to brief advice in individuals with PHP.

Methods

Twenty participants with PHP will be randomly allocated to one of two groups for a 12-week intervention period: (i) foot exercise plus education, or (ii) brief advice. The foot exercise plus education group will attend eight sessions with a physiotherapist and receive detailed education on self-management strategies as well as a progressive exercise program for the IFMs. The brief advice group will attend one session with a physiotherapist and receive brief information about self-management strategies and reassurance. Outcome measures will be obtained at baseline and the primary end-point of 12 weeks. Primary outcomes will be the feasibility of conducting a full-scale randomised clinical trial (RCT), and the credibility and acceptability of the foot exercise plus education intervention. Secondary outcomes will explore treatment effects, which will consist of pain, physical function, physical activity level, pain self-efficacy, perceived treatment effect, magnetic resonance and ultrasound image measurement of IFM morphology, ultrasound imaging measurement of plantar fascia thickness, IFM motor performance, foot posture, foot mobility, ankle dorsiflexion range of motion, toe flexor and plantar flexor strength/endurance.

Discussion

To reduce the burden of PHP on individuals and society, there is a need to establish effective treatments that are feasible and accepted by patients and health professionals. This trial will be the first to evaluate the feasibility of conducting a full-scale RCT, as well as the credibility, acceptability, and treatment effects, of education and foot exercise for PHP. The findings of this study will inform the development of a full-scale RCT.

Trial registration

The trial protocol was prospectively registered with the Australia and New Zealand Clinical Trial Registry (ACTRN12619000987167) on 11th July 2019.

Ultrasound-Guided Injection of High Molecular Weight Hyaluronic Acid versus Corticosteroid in Management of Plantar Fasciitis: A 24-Week Randomized Clinical Trial

BACKGROUND AND AIMS

Plantar fasciitis (PF) is the leading cause of heel pain in adults. This study was designed to evaluate the effect of hyaluronic acid (HA) injection in reducing the symptoms of PF, compared with corticosteroid (CS) injection as a conventional treatment.

METHODS

In this triple-blind, randomized, clinical trial, 75 patients who had the symptoms of PF for at least 3 months were randomly divided into two groups of 38 and 37 individuals. Then, each patient received either a single injection of high molecular weight (>2000 kDa) HA (1 mL HA 20 mg + 1 mL lidocaine 2%) or CS (1 mL methylprednisolone 40 mg + 1 mL lidocaine 2%) under the ultrasonography (US) guidance. Visual analog scale (VAS), foot ankle ability index (FAAI), pressure pain threshold (PPT), functional foot index (FFI), and plantar fascia thickness (PFT) were measured using US at baseline, 6 weeks and 24 weeks after the injection. Eventually, at the end of the treatment period, the patients' satisfaction was measured. Intention to treat analysis was used to assess the results.

RESULTS

After 24 weeks of follow-up, results from 60 subjects were fully obtained; however, results of 73 patients included into intention to treat analysis in the sixth-week follow-up. In both groups, VAS, PFT and FFI decreased, while FAAI and PPT increased significantly (P <0.001). At the baseline and at the 24th-week, no significant difference between the two groups was observed in any of the variables. However, a comparison between the baseline and the sixth-week results shows a prominent decrease in PPT and PFT in the CS group compared to the HA group (P = 0.004 and P = 0.011). Finally, there were no statistical differences between the two groups in treatment satisfaction (P = 0.618).

CONCLUSION

Both CS and HA were effective modalities for PF and can improve pain and function with no superiority in 24th-week follow-ups, although CS seems to have a faster trend of improvement in the short term.

Topographical Pressure Pain Sensitivity Maps of the Feet Reveal Bilateral Pain Sensitivity in Patients With Unilateral Plantar Heel Pain

BACKGROUND

Plantar heel pain is one of the most common foot pain conditions treated by health care providers.

OBJECTIVES

To investigate differences in topographical pressure pain sensitivity maps of the feet between patients with unilateral plantar heel pain and healthy individuals, and to determine the relationship between topographical pressure maps, pain intensity, disability, and fascia thickness.

METHODS

Thirty-five patients with unilateral plantar heel pain and 35 matched healthy controls participated in this cross-sectional, case-control study. Pressure pain thresholds (PPTs) were assessed over 7 plantar locations on each foot. Topographical pressure pain sensitivity maps of the plantar region were generated using the averaged PPT of each assessed point. Pain and related disability were assessed with a numeric pain-rating scale (0-10) and the Foot and Ankle Ability Measure, respectively. Plantar fascia thickness was measured via ultrasound. All outcomes were obtained by an assessor blinded to the participants' condition.

RESULTS

Topographical pressure sensitivity maps revealed lower bilateral PPTs in patients with plantar heel pain compared to healthy controls, and a higher PPT on the calcaneus bone (P<.01). Women had lower PPTs than men in all areas (P<.001). Individuals with plantar heel pain also had thicker fascia, but only on the affected side, compared to healthy controls. Higher pressure pain sensitivity in the foot was associated with higher pain intensity at first step in the morning and thicker fascia at the calcaneus bone.

CONCLUSION

People with unilateral plantar heel pain had generalized bilateral pressure pain sensitivity in the plantar region of the foot. Greater pain intensity and fascia thickness were associated with higher pressure pain sensitivity in people with plantar heel pain.

LEVEL OF EVIDENCE

Case-control study, level 4. J Orthop Sports Phys Ther 2019;49(9):640-646. Epub 26 Mar 2019. doi:10.2519/jospt.2019.8813.

Heavy-slow resistance training in addition to an ultrasound-guided corticosteroid injection for individuals with plantar fasciopathy: a feasibility study

INTRODUCTION

Plantar fasciopathy, characterised by plantar heel pain, affects one in ten in a lifetime. Heavy-slow resistance training (HSR) is an emerging treatment, but it often takes considerable time before the effect starts to manifest. Combining HSR with a corticosteroid injection (known for its short-term pain relief) could potentially improve outcomes in both short and long term. As this combination is yet to be investigated, we aimed to evaluate the feasibility of combining HSR with a corticosteroid injection for individuals with plantar fasciopathy before investigating the efficacy in a clinical trial.

MATERIALS AND METHODS

We recruited 20 participants with plantar fasciopathy for this prospectively registered feasibility study (ClinicalTrials.gov: NCT03535896). Participants received an ultrasound-guided injection and performed heel raises on a step every second day for 8 weeks. To assess participant acceptability of the combined interventions and exercise compliance, we used a 7-point Likert scale dichotomised to "unacceptable" (categories 1-2) or "acceptable" (categories 3-7) and training diaries. Greater than or equal to 10/20 had to rate the combination "acceptable", ≥ 15/20 had to perform ≥ 20 training sessions, and ≥ 15/20 had to start exercising ≤ 7 days after injection to confirm feasibility.

RESULTS

Eighteen out of 20 rated the combination acceptable. Five training diaries could not be retrieved. Ten out of 15 participants performed ≥ 20 training sessions, and 15/15 started exercising ≤ 7 days after injection.

CONCLUSIONS

Based on participant acceptability and time to exercise start, combining HSR with corticosteroid injection is feasible and the efficacy should be investigated in a future trial. Due to loss of 5/20 training diaries, firm conclusions regarding exercise compliance could not be drawn.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03535896.

Assessment the reliability of ultrasonography in the imaging of the plantar fascia: a comparative study

BACKGROUND

Imaging methods for the plantar fascia have included radiography, ultrasound and magnetic resonance imaging (MRI), all of which have provided valuable information. This study assessed the reliability of ultrasonography examinations of the plantar fascia using a comparative study.

METHODS

Fifty healthy adult volunteers (25 males and 25 females, mean age 31.6 ± 3.5 years) were included in this study. Images of the plantar fascia from 100 ft were acquired with ultrasonography, CT and MRI. Ultrasound was used to measure the thickness of the plantar fascia. Imaging data from CT and MRI in a DICOM format were transformed into the Materialise Mimics Innovation Suite 16.0 software for digital analysis. SPSS software (SPSS, USA) was used for statistical analysis. The reliability was established by a t-test. Moreover, 42 patients with unilateral plantar fasciitis were examined by ultrasonography.

RESULTS

There were no significant differences between the three imaging modalities for patients of the same sex (P > 0.05). There were no statistically significant differences between the left and right sides for patients of the same sex (P > 0.05), but the difference between males and females was statistically significant (P < 0.01). There were no significant differences between US, CT and MRI in the normal group, but there were significant differences in the plantar fasciitis group evaluated with ultrasound. The plantar fascii of normal male subjects are significantly thicker than those of the normal female.

CONCLUSION

Ultrasonography can be a relatively simple and reliable method for the measurement of plantar fascia thickness.

Self-dosed and pre-determined progressive heavy-slow resistance training have similar effects in people with plantar fasciopathy: a randomised trial

QUESTION

For people with plantar fasciopathy, is a 12-week self-dosed heavy-slow resistance training program more beneficial than a 12-week pre-determined heavy-slow resistance training program?

DESIGN

A randomised trial with concealed allocation, partial blinding, and intention-to-treat analysis.

PARTICIPANTS

Seventy people with plantar fasciopathy confirmed on ultrasonography.

INTERVENTION

Both groups performed a repeated heel raise exercise in standing for 12 weeks. Participants in the experimental group were self-dosed (ie, they performed as many sets as possible with as heavy a load as possible, but no heavier than 8 repetition maximum). The exercise regimen for the control group was pre-determined (ie, it followed a standardised progressive protocol).

OUTCOME MEASURES

The primary outcome was the Foot Health Status Questionnaire pain domain. Secondary outcomes included: a 7-point Likert scale of Global Rating of Change dichotomised to 'improved' or 'not improved'; Patient Acceptable Symptom State defined as when participants felt no further need for treatment; and number of training sessions performed.

RESULTS

There was no significant between-group difference in the improvement of Foot Health Status Questionnaire pain after 12 weeks (adjusted MD -6.9 points, 95% CI -15.5 to 1.7). According to the Global Rating of Change, 24 of 33 in the experimental group and 20 of 32 in the control group were improved (RR = 1.16, 95% CI 0.83 to 1.64). Only four participants achieved Patient Acceptable Symptom State: three of 35 in the experimental group and one of 35 in the control group. No significant between-group difference was found in the number of training sessions that were performed (MD -2 sessions, 95% CI -8 to 3).

CONCLUSION

Self-dosed and pre-determined heavy-slow resistance exercise programs are associated with similar effects on plantar fasciopathy pain and other outcomes over 12 weeks. Advising people with plantar fasciopathy to self-dose their slow-heavy resistance training regimen did not substantially increase the achieved dose compared with a pre-determined regimen. These regimens are not sufficient to achieve acceptable symptom state in the majority of people with plantar fasciopathy.

REGISTRATION

ClinicalTrials.govNCT03304353.

Ultrasonographic assessment of patellar tendon thickness at 16 clinically relevant measurement sites - A study of intra- and interrater reliability

OBJECTIVES

To determine intra- and interrater reliability of ultrasonographic imaging (USI) measurements of patellar tendon (PT) thickness using 16 measurement sites covering the entire tendon.

DESIGN

Reliability study.

SETTING

Physiotherapy outpatient clinic.

PARTICIPANTS

Twenty healthy and physically active volunteers (9 women). Mean age: 24 years (SD ± 2.73). Mean body mass: 75.8 kg (SD ± 11.8).

MAIN OUTCOME MEASURES

Intraclass correlation coefficient (ICC) and 95% limits of agreement (LOA) in cm and in percentage relative to the mean PT thickness.

RESULTS

Intrarater reliability ranged from 0.59 to 0.87 and 0.59 to 0.93 for examiners I and II, respectively. Interrater reliability ranged from 0.37 to 0.89. Measurement precision for examiner I ranged from 0.05 to 0.09 cm (17.5%-26.7%) while ranging from 0.04 to 0.13 cm (13.3%-38.7%) for examiner II. Interrater measurement precision ranged from 0.07 to 0.15 cm (19.1%-42.5%).

CONCLUSION

In an attempt to replicate daily clinical USI practice, this was the first study extensively assessing reliability throughout the full range of the patellar tendon - revealing a considerable variation in intra- and interrater reliability as well as measurement precision throughout the 16 individual PT sites. In a clinical context, the low interrater reliability and precision found at the proximal tendon insertion site may have implications for USI of the symptomatic PT, as this is the site mainly associated with underlying pathologic changes. Further reliability studies are needed to clarify the region-specific reliability of the full length PT.

Ultrasonography Features of the Plantar Fascia Complex in Patients with Chronic Non-Insertional Achilles Tendinopathy: A Case-Control Study

Purpose: The goal of the present study was to assess, by ultrasound imaging (USI), the thickness of the plantar fascia (PF) at the insertion of the calcaneus, mid and forefoot fascial locations, and the calcaneal fat pad (CFP) in patients with Achilles tendinopathy (AT). Methods: An observational case-control study. A total sample of 143 individuals from 18 to 55 years was evaluated by USI in the study. The sample was divided into two groups: A group composed of the chronic non-insertional AT (n = 71) and B group comprised by healthy subjects (n = 72). The PF thicknesses at insertion on the calcaneus, midfoot, rearfoot and CFP were evaluated by USI. Results: the CFP and PF at the calcaneus thickness showed statistically significant differences (P < 0.01) with a decrease for the tendinopathy group with respect to the control group. For the PF midfoot and forefoot thickness, no significant differences (P > 0.05) were observed between groups. Conclusion: The thickness of the PF at the insertion and the CPF is reduced in patients with AT measured by USI.

Effect of Gender, Toe Extension Position, and Plantar Fasciitis on Plantar Fascia Thickness

BACKGROUND:

Ultrasound is a widely used diagnostic tool for patients with plantar fasciitis. However, the lack of standardization during the measurement for plantar fascia thickness has made it challenging to understand the etiology of plantar fasciitis, as well as identify risk factors, such as gender. The purpose of this study was to investigate gender differences regarding plantar fascia thickness while controlling for metatarsophalangeal (MTP) joint position in the healthy and those with unilateral plantar fasciitis.

METHODS:

Forty participants (20 with unilateral plantar fasciitis and 20 controls) with plantar fascia thickness (mean age, 44.8 ± 12.2 years) participated in this study. The majority were females (n = 26, 65%). Plantar fascia thickness was measured via ultrasound 3 times at 3 different MTP joint positions: (1) at rest, (2) at 30 degrees of extension, and (3) at maximal extension.

RESULTS:

When comparing gender differences, the males in the plantar fasciitis group had a significantly thicker plantar fascia than the females ( P = .048, η² = 2.35). However, no significant differences were observed between healthy males and females. The males with unilateral plantar fasciitis also had significantly thicker asymptomatic plantar fasciae collectively compared with controls ( P < .05), whereas females with unilateral plantar fasciitis had a similar but not significant change.

CONCLUSION:

It appears that healthy males and females have similar plantar fascia thickness. However, as plantar fasciitis develops, males tend to develop thicker plantar fasciae than their female counterparts, which could have future treatment implications.

LEVEL OF EVIDENCE:

Level III, case-control comparative study.

Effect of toe dorsiflexion on the regional distribution of plantar fascia shear wave velocity

BACKGROUND

The plantar fascia is exposed to repetitive tensile stress induced by cyclic loads associated with daily activities, such as walking and running. Due to overuse or abnormal foot alignment, insertional and distal (i.e., mid-substance) regions within the plantar fascia may exhibit microtears, which leads to plantar fasciopathy. Ultrasound shear wave elastography is an imaging technique to measure shear wave velocity propagating through biological tissues, considered herein as an index of tensile stress. This study aimed to quantify the effect of toe dorsiflexion on the regional distribution of plantar fascia shear wave velocity.

METHODS

Shear wave velocity of the plantar fascia was measured in the insertional and distal regions using ultrasound shear wave elastography in sixteen healthy participants (7 males and 9 females). The measurements were performed while the toes were maintained in neutral or dorsiflexed positions.

FINDINGS

When considering the insertional region, there was no significant difference in shear wave velocity between neutral toe position [mean (SEM): 5.4 (0.6) m/s] and dorsiflexed toe position [5.5 (0.5) m/s] (P = 0.88; effect size = 0.05). When considering the distal region, there was a significant difference in shear wave velocity between the neutral position [7.8 (0.4) m/s] and dorsiflexed position [9.9 (0.3) m/s] (P = 0.002; effect size = 0.88). The difference in shear wave velocity between the insertional and distal regions showed a large effect size for either neutral (P = 0.010; effect size = 0.75) or dorsiflexed toe position (P = 0.003; effect size = 0.86).

INTERPRETATION

In contrast to clinical beliefs, these findings suggest that toe dorsiflexion induces non-homogeneous changes in tensile stress within the plantar fascia.

Ultrasonographic evaluation of the ankle after unilateral traumatic lower limb amputations

BACKGROUND

Unilateral lower limb amputation can alter the tissue morphology leading to increase future risk of degenerative secondary disorders.

METHODS

Thirty-four consecutive male patients with unilateral lower limb amputations of different levels and 34 well matched male controls were included. To explore whether the ankles of traumatic lower limb amputees were undergoing morphological changes, three different tissue types i.e. talar cartilage, plantar fascia and Achilles tendon thicknesses in the intact limb of the lower limb amputee and healthy controls were measured by using ultrasound.

RESULTS

Plantar fascia was found to be thicker (p=0.013) and talar cartilage was thinner (p<0.001) on the intact sides of the patients than those of the controls. Achilles tendon thickness was found to be similar. In patients group, plantar fascia thickness was positively correlated with age (r=0.601, p<0.001), BMI (r=0.454, p=0.007) and durations of amputation (r=0.443, p=0.009) and prosthetic use (r=0.429, p=0.011). Achilles tendon thickness was positively correlated with durations of amputation (r=0.338, p=0.05) and prosthetic use (r=0.468, p=0.005). In controls group, talar cartilage thickness was negatively correlated with age (r=-0.640, p<0.001) and BMI (r=-0.401, p=0.019).

CONCLUSIONS

The talar cartilage seemed to be thinner and the plantar fascia to be thicker on the intact sides of the unilateral limb amputees.

Fascia thickness, aging and flexibility: is there an association?

The morphology of the connective tissue may play an important role in locomotor mechanics. Recent research has revealed an association between increased fascia thickness and reduced joint flexibility in patients with chronic pain. The present study aimed to examine the relationship of both factors in healthy individuals, additionally testing the hypothesis that older subjects display a higher fascia thickness. Young (n = 18, 22 ± 1 years) and old (n = 17, 69 ± 4 years) healthy females were recruited for a quasi-experimental, cross-sectional trial. All participants underwent standardized ultrasound-based thickness measurements of the deep fasciae of the trunk and lower limb. Flexibility was assessed using sit and reach testing (hamstring extensibility) and the Schober test (lumbar flexion and extension). Systematic between-group differences of fascia thickness and variable associations (i.e. fascia thickness and flexibility) were detected using non-parametric data analyses. Young adults exhibited higher fascia thickness of the anterior and posterior lower leg, anterior thigh and abdominal wall (+12.3-25.8%, P < 0.05). Conversely, older participants showed higher thickness in the lumbar spine (+40.0-76.7%, P < 0.05). Correlations of both body mass and fascia thickness (τ = 0.45-0.75, P < 0.05), as well as flexibility and fascia thickness (τ = 0.38-0.42, P < 0.05) were found. Age-related changes in fascia thickness may be a contributing factor of restrictions in joint range of motion. Further study delineating the cause-effect triangle of body mass index, flexibility and fascia thickness is necessary.

The effect of isometric exercise on pain in individuals with plantar fasciopathy: A randomized crossover trial

Isometric exercise is commonly recommended for immediate pain relief in individuals suffering from lower limb tendinopathies, despite the limited evidence supporting its analgesic effect. Due to the similarities between plantar fasciopathy and tendinopathies, the aim of this trial was to investigate the acute effect of isometric exercise on pain, compared to isotonic exercise, or walking, in individuals with plantar fasciopathy. We recruited 20 individuals with plantar fasciopathy for this prospectively-registered, participant-blinded, randomized, superiority crossover trial (ClinicalTrials.gov: NCT03264729). Participants attended three exercise sessions (isometric, isotonic, or walking) in a randomized order, within a 2-week period. Both isometric and isotonic exercises were performed standing with the forefoot on a step bench, while walking was performed barefoot. The primary outcome was pain (measured on a 0-100-mm VAS) during a pain-aggravating activity. Secondary outcomes included pressure pain threshold (PPT) under the heel, and plantar fascia thickness (PFT). All outcomes were measured before and after each exercise session. There were no significant differences between the three exercises on pain (P = 0.753), PPTs (P = 0.837), or PFT (P = 0.718). Further, there was no change in pain from before to after any of the exercises (isometric exercise 2.7 mm [95% CI: -12.2; 6.8], isotonic exercise -3.4 mm [95% CI: -5.0; 11.8], or walking 1.6 mm [95% CI: -16.1; 12.9]). Contrary to expectations, isometric exercise was no better than isotonic exercise or walking at reducing pain in individuals with plantar fasciopathy. None of the exercises induced any systematic analgesic effect.

Metatarsophalangeal joint extension changes ultrasound measurements for plantar fascia thickness

Background

Ultrasound is an inexpensive method for quantifying plantar fascia thickness, especially in those with plantar fasciitis. Ultrasound has also been used to assess the effectiveness of various treatments for plantar fasciitis by comparing plantar fascia thickness before and after an intervention period. While a plantar fascia thickness over 4 mm via ultrasound has been proposed to be consistent with plantar fasciitis, some researchers believe the 4 mm plantar fascia thickness level to be a dubious guideline for diagnosing plantar fasciitis due to the lack of standardization of the measurement process for plantar fascia thickness. In particular, no universal guidelines exist on the positioning of the metatarsophalangeal (MTP) joints during the procedure and the literature also has inconsistent protocols. The purpose of this study is to investigate and compare the influence of MTP joint extension on plantar fascia thickness in healthy participants and those with unilateral plantar fasciitis.

Methods

The plantar fascia thickness of forty participants (20 with unilateral plantar fasciitis and 20 control) was measured via ultrasound three times at three different MTP joint positions: 1) at rest, 2) 30° of extension from the plantar surface, and 3) maximal extension possible.

Results

The plantar fascia became significantly thinner as MTP joint extension increased in both the plantar fasciitis group (p < 0.001) and the control group (p < 0.001). In the plantar fasciitis group, the involved plantar fascia was 1.2 to 1.3 mm thicker (p < 0.001) than the uninvolved side depending on the MTP joint position. In the control group, the difference in plantar fascia thickness between the two sides was less than 0.1 mm (p < 0.92) at any MTP joint position.

Conclusions

MTP joint position can influence the ultrasound measurement of plantar fascia thickness. It is recommended that plantar fascia thickness measurements be performed with the toes at rest. If MTP joints must be extended, then the toes should be extended maximally and then noted to ensure subsequent ultrasound procedures are repeated. Standardizing the position of the MTP joints is not only important for attaining the most accurate thickness measurement of the plantar fascia, but is also important to researchers who use plantar fascia thickness to determine the effectiveness of various plantar fasciitis interventions.

Long-Term Prognosis of Plantar Fasciitis: A 5- to 15-Year Follow-up Study of 174 Patients With Ultrasound Examination

Background:

Plantar fasciitis (PF) affects 7% to 10% of the population. The long-term prognosis is unknown.

Purpose:

Our study had 4 aims: (1) to assess the long-term prognosis of PF, (2) to evaluate whether baseline characteristics (sex, body mass index, age, smoking status, physical work, exercise-induced symptoms, bilateral heel pain, fascia thickness, and presence of a heel spur) could predict long-term outcomes, (3) to assess the long-term ultrasound (US) development in the fascia, and (4) to assess whether US-guided corticosteroid injections induce atrophy of the heel fat pad.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

From 2001 to 2011 (baseline), 269 patients were diagnosed with PF based on symptoms and US. At follow-up (2016), all patients were invited to an interview regarding their medical history and for clinical and US re-examinations. Kaplan-Meier survival estimates were used to estimate the long-term prognosis, and a multiple Cox regression analysis was used for the prediction model.

Results:

In all, 174 patients (91 women, 83 men) participated in the study. All were interviewed, and 137 underwent a US examination. The mean follow-up was 9.7 years from the onset of symptoms and 8.9 years from baseline. At follow-up, 54% of patients were asymptomatic (mean duration of symptoms, 725 days), and 46% still had symptoms. The risk of having PF was 80.5% after 1 year, 50.0% after 5 years, 45.6% after 10 years, and 44.0% after 15 years from the onset of symptoms. The risk was significantly greater for women (P < .01) and patients with bilateral pain (P < .01). Fascia thickness decreased significantly in both the asymptomatic and symptomatic groups (P < .01) from 6.9 mm and 6.7 mm, respectively, to 4.3 mm in both groups. Fascia thickness (P = .49) and presence of a heel spur (P = .88) at baseline had no impact on prognosis. At follow-up, fascia thickness and echogenicity had normalized in only 24% of the asymptomatic group. The mean fat pad thickness was 9.0 mm in patients who had received a US-guided corticosteroid injection and 9.4 mm in those who had not been given an injection (P = .66).

Conclusion:

The risk of having PF in this study was 45.6% at a mean 10 years after the onset of symptoms. The asymptomatic patients had PF for a mean 725 days. The prognosis was significantly worse for women and patients with bilateral pain. Fascia thickness decreased over time regardless of symptoms and had no impact on prognosis, and neither did the presence of a heel spur. Only 24% of asymptomatic patients had a normal fascia on US at long-term follow-up. A US-guided corticosteroid injection did not cause atrophy of the heel fat pad. Our observational study did not allow us to determine the efficacy of different treatment strategies.

Ultrasound measures of tendon thickness: Intra-rater, Inter-rater and Inter-machine reliability

BACKGROUND

Ultrasound imaging is often used by physiotherapists and other healthcare professionals but the reliability of image acquisition with different ultrasound machines is unknown. The objective was to compare the intra-rater, inter-rater and intermachine reliability of thickness measurements of the plantar fascia (PF), Achilles tendon (AT), patellar tendon (PT) and elbow common extensor tendon (ECET) with musculoskeletal ultrasound imaging (MSUS).

METHODS

Tendon thickness was measured in four anatomical structures (14 participants, 28 images per tendon) by two sonographers and with two different ultrasound machines. Intraclass Correlation Coefficients (ICCs) and Bland-Altman plots were calculated. The standard error of measurement (SEM) and minimum detectable difference (MDD) were calculated.

RESULTS

Inter-rater reliability was excellent for AT (ICC=0.98; 95% CI= 0.96-0.99) and very good for PT (ICC=0.85; 95% CI = 0.67-0.93) and ECET (ICC=0.81; 95% CI= 0.72-0.94). Reliability for PF was moderate, with an ICC of 0.63 (CI 95%= 0.20-0.83). Bland-Altman plot for inter-machine reliability showed a mean difference of 1 m for PF measurements and a mean difference of 4 m and 20 m for AT and PT. The relative SEMs were below 7% and the MDCs were below 0.7 mm.

CONCLUSION

The MSUS reliability in measuring thickness of the four tendons is confirmed by the homogeneous readings intra sonographers, between operators and between different machines. Level of evidence: Tendon thickness can be measured reliably on different ultrasound devices, which is an important step forward in the use of this technique in daily clinical practice and research.

LEVEL OF EVIDENCE

III.

Sonographic measurements of the achilles tendon, plantar fascia, and heel fat pad are reliable: A test-retest intra- and intertester study

PURPOSE

To determine intra- and interobserver reliability and precision of sonographic (US) scanning in measuring thickness of the Achilles tendon, plantar fascia, and heel fat pad in patients with heel pain.

METHODS

Seventeen consecutive patients referred with heel pain were included. Two evaluators blinded to the diagnosis performed independently US scanning of both feet without any dialogue with the patient. The examiner left the room, and the next examiner entered. All patients had two US scans performed by each examiner. Two months later, the US images were randomly presented to the evaluators for measurements. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC), 95% limits of agreement (LOA), and typical error (TE). LOA was calculated as a percentage of the mean thickness of each structure to obtain a unitless parameter.

RESULTS

We found excellent intratester reliability (ICC 0.78-0.98) and good intertester reliability using one measurement (ICC 0.72-0.91) and excellent (ICC 0.85-0.95) when using average of two measurements. The intratester agreements were good with LOA: 9.5-23.4% and TE: 3.4-8.4%. The intertester agreements were acceptable using one measurement with LOA: 16.1-36.4%, and better using two measurements with LOA: 14.4-33.2%.

CONCLUSIONS

US is a reliable technique of measurement in the daily clinic, and one single measurement is sufficient. In research, we recommend that the same observer performs the US measurements, if one single scanning is preferred; if more researchers are involved, the average measurement of two US scans is recommended. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:480-486, 2016.

Ultrasonographic examination of plantar fasciitis: a comparison of patient positions during examination

BACKGROUND

Musculoskeletal ultrasound is a non-invasive and low-cost modality for real-time visualisation of the plantar fascia. Ultrasound examination for plantar fasciitis is generally performed with the patient in a prone position, although the rational for using a prone position has not been validated. The aim of the study was to investigate if ultrasound examination in a supine position, which is more comfortable than the prone position, is valid.

METHODS

We conducted a prospective study of 30 participants with plantar fasciitis, 8 men (27 %) and 22 women (73 %), with a mean age of 53.9 ± 12.6 (range, 32 to 77) years, and an equal distribution of left and right feet. The plantar heel was divided into three portions for ultrasound examination: medial, central and lateral. Two measurements of plantar fascia thickness were obtained for each portion, with participants in 2 positions (supine and prone) and for 2 ankle postures (neutral and 15° of plantarflexion). Mean measurements of plantar fascia thickness were compared between the two positions (Wilcoxon signed rank tests for non-normally distributed data and paired t-tests for normally distributed data). Participants were asked to report their preferred position for examination, supine or prone.

RESULTS

The measured thickness was comparable for both supine and prone positions, for both ankle postures, neutral and 15° of plantarflexion (p > 0.05). A specific self-reported preferred position was not identified.

CONCLUSIONS

Ultrasound examination of plantar fasciitis can be performed in the supine position without any significant difference in measurement compared to examination in the conventional prone position.

TRIAL REGISTRATION

The Catholic Medical Center Office of Human Research Protection Program (CMC-OHRP)/Institutional Review Board approved the current study (Approval No. KC12DISI0338), and all participants provided their written informed consent for participation and publication.

Reliability of Various Measurement Stations for Determining Plantar Fascia Thickness and Echogenicity

This study aimed to determine the relative and absolute reliability of ultrasound (US) measurements of the thickness and echogenicity of the plantar fascia (PF) at different measurement stations along its length using a standardized protocol. Twelve healthy subjects (24 feet) were enrolled. The PF was imaged in the longitudinal plane. Subjects were assessed twice to evaluate the intra-rater reliability. A quantitative evaluation of the thickness and echogenicity of the plantar fascia was performed using Image J, a digital image analysis and viewer software. A sonography evaluation of the thickness and echogenicity of the PF showed a high relative reliability with an Intra class correlation coefficient of ≥0.88 at all measurement stations. However, the measurement stations for both the PF thickness and echogenicity which showed the highest intraclass correlation coefficient (ICCs) did not have the highest absolute reliability. Compared to other measurement stations, measuring the PF thickness at 3 cm distal and the echogenicity at a region of interest 1 cm to 2 cm distal from its insertion at the medial calcaneal tubercle showed the highest absolute reliability with the least systematic bias and random error. Also, the reliability was higher using a mean of three measurements compared to one measurement. To reduce discrepancies in the interpretation of the thickness and echogenicity measurements of the PF, the absolute reliability of the different measurement stations should be considered in clinical practice and research rather than the relative reliability with the ICC.

Navicular bone position determined by positional MRI: a reproducibility study

OBJECTIVE

To examine intraobserver, interobserver and between-day reproducibility of positional MRI for evaluation of navicular bone height (NVH) and medial navicular position (MNP).

MATERIALS AND METHODS

Positional MRI (pMRI) of the foot was performed on ten healthy participants (0.25 T G-scanner). Scanning was performed in supine and standing position, respectively. Two radiologists evaluated the images in a blinded manner. Reliability and agreement were assessed by calculation of intraclass correlation coefficient (ICC) and 95 % limits of agreement as a percentage of the mean (LOA%).

RESULTS

Intraobserver and interobserver reliability was "substantial" in both supine and standing position (ICC 0.86-0.98) and showed good agreement (LOA% 4.9-14.7 %). Between-day reliability of navicular height and medial navicular position in standing position remained substantial (ICC 0.85-0.92) with adequate agreement (LOA% 8.3-19.8 %). In supine position between-day reliability was "moderate" for NVH (ICC 0.72) and "slight" for MNP (ICC 0.39). Agreement remained adequate between-days for MNP in supine position (LOA% 17.7 %), but it was less than adequate for NVH in supine position (LOA% 24.2 %).

CONCLUSION

Navicular height and medial navicular position can be measured by pMRI in a very reproducible manner within and between observers. Increased measurement variation is observed between-days in supine position, which may be due to small positional differences or other unknown biomechanical factors.

Plantar fascia softening in plantar fasciitis with normal B-mode sonography

OBJECTIVE

To investigate plantar fascia elasticity in patients with typical clinical manifestations of plantar fasciitis but normal plantar fascia morphology on B-mode sonography.

MATERIALS AND METHODS

Twenty patients with plantar fasciitis (10 unilateral and 10 bilateral) and 30 healthy volunteers, all with normal plantar fascia morphology on B-mode sonography, were included in the study. Plantar fascia elasticity was evaluated by sonoelastographic examination. All sonoelastograms were quantitatively analyzed, and less red pixel intensity was representative of softer tissue. Pixel intensity was compared among unilateral plantar fasciitis patients, bilateral plantar fasciitis patients, and healthy volunteers by one-way ANOVA. A post hoc Scheffé's test was used to identify where the differences occurred.

RESULTS

Compared to healthy participants (red pixel intensity: 146.9 ± 9.1), there was significantly less red pixel intensity in the asymptomatic sides of unilateral plantar fasciitis (140.4 ± 7.3, p = 0.01), symptomatic sides of unilateral plantar fasciitis (127.1 ± 7.4, p < 0.001), and both sides of bilateral plantar fasciitis (129.4 ± 7.5, p < 0.001). There were no significant differences in plantar fascia thickness or green or blue pixel intensity among these groups.

CONCLUSION

Sonoelastography revealed that the plantar fascia is softer in patients with typical clinical manifestations of plantar fasciitis, even if they exhibit no abnormalities on B-mode sonography.

Reliability of ultrasound for measurement of selected foot structures

BACKGROUND

Understanding the relationship between the lower leg muscles, foot structures and function is essential to explain how disease or injury may relate to changes in foot function and clinical pathology. The aim of this study was to investigate the inter-operator reliability of an ultrasound protocol to quantify features of: rear, mid and forefoot sections of the plantar fascia (PF); flexor hallucis brevis (FHB); flexor digitorum brevis (FDB); abductor hallucis (AbH); flexor digitorum longus (FDL); flexor hallucis longus (FHL); tibialis anterior (TA); and peroneus longus and brevis (PER).

METHODS

A sample of 6 females and 4 males (mean age 29.1 ± 7.2 years, mean BMI 25.5 ± 4.8) was recruited from a university student and staff population. Scans were obtained using a portable Venue 40 musculoskeletal ultrasound system (GE Healthcare UK) with a 5-13 MHz wideband linear array probe with a 12.7 mm × 47.1mm footprint by two operators in the same scanning session.

RESULTS

Intraclass Correlation Coefficients (ICC) values for muscle thickness (ICC range 0.90-0.97), plantar fascia thickness (ICC range 0.94-0.98) and cross sectional muscle measurements (ICC range 0.91-0.98) revealed excellent inter-operator reliability. The limits of agreement, relative to structure size, ranged from 9.0% to 17.5% for muscle thickness, 11.0-18.0% for plantar fascia, and 11.0-26.0% for cross sectional area measurements.

CONCLUSIONS

The ultrasound protocol implemented in this work has been shown to be reliable. It therefore offers the opportunity to quantify the structures concerned and better understand their contributions to foot function.