Altered tendon characteristics and mechanical properties associated with insertional achilles tendinopathy

Percutaneous ultrasound-guided needle tenotomy for treatment of chronic tendinopathy and fasciopathy: a meta-analysis

OBJECTIVES

To systematically assess the efficacy of percutaneous ultrasound-guided needle tenotomy (PUNT) in the treatment of chronic tendinopathy and fasciopathy.

METHODS

A comprehensive literature search was performed with the following search terms: tendinopathy, tenotomy, needling, Tenex, fasciotomy, ultrasound-guided, and percutaneous. Inclusion criteria consisted of original studies evaluating pain or function improvement after PUNT. Meta-analyses investigating standard mean differences were performed to assess the pain and function improvement.

RESULTS

Thirty-five studies with 1674 participants (1876 tendons) were enrolled in this article. Of which 29 articles were included in meta-analysis and the remaining 9 articles without enough numeric data were included in descriptive analysis. PUNT significantly alleviated pain with the standard mean difference of 2.5 (95% CI: 2.0-3.0; p < 0.05), 2.2 (95% confidence interval (CI): 1.8-2.7; p < 0.05), and 3.6 (95% CI: 2.8-4.5; p < 0.05) points in short-term, intermediate-term, and long-term follow-up intervals, respectively. It was also associated with marked improvement in function with 1.4 (95% CI: 1.1-1.8; p < 0.05), 1.8 (95% CI: 1.3-2.2; p < 0.05), and 2.1 (95% CI: 1.6-2.6; p < 0.05) points, respectively in short-term, intermediate-term, and long-term follow-ups.

CONCLUSION

PUNT improved pain and function at short-term intervals with persistent results on intermediate- and long-term follow-ups. PUNT can be considered an appropriate minimally invasive treatment for chronic tendinopathy with a low rate of complications and failures.

CLINICAL RELEVANCE

Tendinopathy and fasciopathy are two common musculoskeletal complaints that can cause prolonged pain and disability. PUNT as a treatment option could improve pain intensity and function.

KEY POINTS

• The best improvement in pain and function was achieved after the first 3 months following PUNT and was continued to the intermediate- and long-term follow-ups. • No significant difference was found between different tenotomy methods in terms of pain and function improvement. • PUNT is a minimally invasive procedure with promising results and low complication rates for treatments of chronic tendinopathy.

Eccentric Versus Concentric Exercises in Patients With Rheumatoid Arthritis and Rotator Cuff Tendinopathy: A Randomized Comparative Study

OBJECTIVE

To determine the efficacy of concentric vs. eccentric exercise in improving shoulder function, pain, and tendon characteristics for patients with rheumatoid arthritis and rotator cuff tendinopathy.

METHODS

Forty patients with rheumatoid arthritis and rotator cuff tendinopathy were divided into either concentric or eccentric exercise groups, with 20 patients in each group. Patients received 12 sessions at a pace of 3 sessions per week. Shoulder Pain and Disability Index (SPADI), the visual analogue scale (VAS), supraspinatus and subscapularis thickness, echo pixels, and the Disease Activity Score-28-erythrocyte sedimentation rate (DAS-28-ESR) were assessed at baseline and post-treatment.

RESULTS

There was a significant difference between the concentric and eccentric groups regarding SPADI and VAS scores in favor of the eccentric group. However, there was no significant difference between the two groups regarding tendon thickness, echo pixels, or DAS-28-ESR.

CONCLUSION

Eccentric exercises were more effective than concentric exercises in improving shoulder function and pain intensity. However, neither of the two types of exercises was superior in improving tendon characteristics or disease activity.

Musculoskeletal Ultrasound Image-Based Radiomics for the Diagnosis of Achilles Tendinopathy in Skiers

OBJECTIVES

Our study aimed to develop and validate an efficient ultrasound image-based radiomic model for determining the Achilles tendinopathy in skiers.

METHODS

A total of 88 feet of skiers clinically diagnosed with unilateral chronic Achilles tendinopathy and 51 healthy feet were included in our study. According to the time order of enrollment, the data were divided into a training set (n = 89) and a test set (n = 50). The regions of interest (ROIs) were segmented manually, and 833 radiomic features were extracted from red, green, blue color channels and grayscale of ROIs using Pyradiomics, respectively. Three feature selection and three machine learning modeling algorithms were implemented respectively, for determining the optimal radiomics pipeline. Finally, the area under the receiver operating characteristic curve (AUC), consistency analysis, and decision analysis were used to evaluate the diagnostic performance.

RESULTS

By comparing nine radiomics analysis strategies of three color channels and grayscale, the radiomic model under the green channel obtained the best diagnostic performance, using the Random Forest selection and Support Vector Machine modeling, which was selected as the final machine learning model. All the selected radiomic features were significantly associated with the Achilles tendinopathy (P < .05). The radiomic model had a training AUC of 0.98, a test AUC of 0.99, a sensitivity of 0.90, and a specificity of 1, which could bring sufficient clinical net benefits.

CONCLUSIONS

Ultrasound image-based radiomics achieved high diagnostic performance, which could be used as an intelligent auxiliary tool for the diagnosis of Achilles tendinopathy.

In Achilles Tendinopathy the Symptomatic Tendon Differs from the Asymptomatic Tendon While Exercise Therapy Has Little Effect on Asymmetries-An Ancillary Analysis of Data from a Controlled Clinical Trial

BACKGROUND

As inter-limb asymmetries can be associated with higher injury risk, we aimed to investigate their role in Achilles tendinopathy patients.

METHODS

In Achilles tendinopathy patients (n = 41), we assessed inter-limb asymmetries of mechanical, material, and morphological musculoskeletal properties and function and how those were affected by 12 weeks of exercise intervention (high-load protocol, n = 13; Alfredson protocol, n = 11). Moreover, we assessed whether asymmetry reductions correlated with improved Patient-Reported Outcomes (VISA-A score).

RESULTS

At baseline, tendinopathic tendons demonstrated lower tendon force (p = 0.017), lower tendon stress (p < 0.0001), larger tendon cross-sectional area (CSA) (p < 0.001), and increased intratendinous (p = 0.042) and tendon overall (p = 0.021) vascularization. For the high-load group, PRE-to-POST asymmetry comparisons revealed an asymmetry increase for the counter-movement jump (CMJ) (p = 0.034) and PRE-to-POST VISA-A score improvements correlated with CSA asymmetry reductions (p = 0.024). Within the Alfredson group, PRE-to-POST VISA-A score improvements correlated with CMJ asymmetry reductions (p = 0.044) and tendon stiffness asymmetry increases (p = 0.037). POST-to-POST in-between group comparisons revealed lower asymmetry in the high-load group for tendon elongation (p = 0.021) and tendon strain (p = 0.026).

CONCLUSIONS

The tendinopathic limb differs from the asymptomatic limb while therapeutic exercise interventions have little effect on asymmetries. Asymmetry reductions are not necessarily associated with tendon health improvements.

Biomechanics and lower limb function are altered in athletes and runners with achilles tendinopathy compared with healthy controls: A systematic review

Achilles tendinopathy (AT) is a debilitating injury in athletes, especially for those engaged in repetitive stretch-shortening cycle activities. Clinical risk factors are numerous, but it has been suggested that altered biomechanics might be associated with AT. No systematic review has been conducted investigating these biomechanical alterations in specifically athletic populations. Therefore, the aim of this systematic review was to compare the lower-limb biomechanics of athletes with AT to athletically matched asymptomatic controls. Databases were searched for relevant studies investigating biomechanics during gait activities and other motor tasks such as hopping, isolated strength tasks, and reflex responses. Inclusion criteria for studies were an AT diagnosis in at least one group, cross-sectional or prospective data, at least one outcome comparing biomechanical data between an AT and healthy group, and athletic populations. Studies were excluded if patients had Achilles tendon rupture/surgery, participants reported injuries other than AT, and when only within-subject data was available.. Effect sizes (Cohen's d) with 95% confidence intervals were calculated for relevant outcomes. The initial search yielded 4,442 studies. After screening, twenty studies (775 total participants) were synthesised, reporting on a wide range of biomechanical outcomes. Females were under-represented and patients in the AT group were three years older on average. Biomechanical alterations were identified in some studies during running, hopping, jumping, strength tasks and reflex activity. Equally, several biomechanical variables studied were not associated with AT in included studies, indicating a conflicting picture. Kinematics in AT patients appeared to be altered in the lower limb, potentially indicating a pattern of "medial collapse". Muscular activity of the calf and hips was different between groups, whereby AT patients exhibited greater calf electromyographic amplitudes despite lower plantar flexor strength. Overall, dynamic maximal strength of the plantar flexors, and isometric strength of the hips might be reduced in the AT group. This systematic review reports on several biomechanical alterations in athletes with AT. With further research, these factors could potentially form treatment targets for clinicians, although clinical approaches should take other contributing health factors into account. The studies included were of low quality, and currently no solid conclusions can be drawn.

Foundational Principles and Adaptation of the Healthy and Pathological Achilles Tendon in Response to Resistance Exercise: A Narrative Review and Clinical Implications

Therapeutic exercise is widely considered a first line fundamental treatment option for managing tendinopathies. As the Achilles tendon is critical for locomotion, chronic Achilles tendinopathy can have a substantial impact on an individual's ability to work and on their participation in physical activity or sport and overall quality of life. The recalcitrant nature of Achilles tendinopathy coupled with substantial variation in clinician-prescribed therapeutic exercises may contribute to suboptimal outcomes. Further, loading the Achilles tendon with sufficiently high loads to elicit positive tendon adaptation (and therefore promote symptom alleviation) is challenging, and few works have explored tissue loading optimization for individuals with tendinopathy. The mechanism of therapeutic benefit that exercise therapy exerts on Achilles tendinopathy is also a subject of ongoing debate. Resultingly, many factors that may contribute to an optimal therapeutic exercise protocol for Achilles tendinopathy are not well described. The aim of this narrative review is to explore the principles of tendon remodeling under resistance-based exercise in both healthy and pathologic tissues, and to review the biomechanical principles of Achilles tendon loading mechanics which may impact an optimized therapeutic exercise prescription for Achilles tendinopathy.

Impingement in Insertional Achilles Tendinopathy Occurs Across a Larger Range of Ankle Angles and Is Associated With Increased Tendon Thickness

BACKGROUND

Insertional Achilles tendinopathy (IAT) is characterized by tendon degeneration and thickening near the tendon-bone insertion.¹¹ Calcaneal impingement is believed to contribute to the pathogenesis of IAT.⁵ However, it is unclear how increased tendon thickness in individuals with IAT influences impingement. This study aimed to compare Achilles tendon impingement in individuals with and without IAT.

METHODS

Eight healthy adults and 12 adults with clinically diagnosed symptomatic IAT performed a passive flexion exercise during which ankle flexion angle, anterior-posterior (A-P) thickness, and an ultrasonographic image sequence of the Achilles tendon insertion were acquired. The angle of ankle plantarflexion at which the calcaneus first impinges the Achilles tendon, defined as the impingement onset angle, was identified by (1) a anonymized observer (visual inspection method) and (2) a computational image deformation-based approach (curvature method).

RESULTS

Although the 2 methods provided different impingement onset angles, the measurements were strongly correlated (R² = 0.751, P < .05). The impingement onset angle and the thickness of the Achilles tendon insertion were greater in subjects with clinically diagnosed IAT (P = .0048, P = .0047). Furthermore, impingement onset angle proved to have a moderate correlation with anterior-posterior thickness (R² = 0.454, P < .05).

CONCLUSION

Our findings demonstrated that increased tendon thickness in IAT patients is associated with larger impingement onset angles, raising the range of ankle angles over which the tendon is exposed to impingement.

CLINICAL RELEVANCE

Increased susceptibility to impingement may exacerbate or perpetuate the pathology, highlighting the need for clinical strategies to reduce impingement in IAT patients.

Chronic adaptations of the long head of the biceps tendon and groove in professional baseball pitchers

BACKGROUND AND HYPOTHESIS

The long head of the biceps tendon (LHBT) plays a significant shoulder stabilizing role during pitching, with the large forces and repetitions involved in overhead throwing likely contributing to LHBT pathology. Determining whether the LHBT undergoes adaptive changes in baseball pitchers and how these changes relate to bicipital groove morphology can improve our understanding of the biceps function at the glenohumeral joint. Therefore, the purpose of this study was to determine the chronic adaptations of the bicipital groove morphology and the LHBT in professional baseball pitchers, with a secondary purpose of evaluating biceps integrity as it relates to torsional changes of the bicipital groove. We hypothesized that the throwing arm of professional baseball pitchers would exhibit chronic adaptations of the LHBT compared with their nonthrowing arm, and that these adaptations would be related to the bicipital groove morphology.

MATERIALS AND METHODS

Fifty-three professional baseball pitchers were enrolled at the beginning of the 2015 Major League Baseball spring training. Ultrasound was used to bilaterally measure humeral retroversion and to capture images of the bicipital groove and the LHBT. MATLAB software was used to calculate the area of the bicipital groove, and ImageJ software was used to quantify the area, echogenicity, and circularity of the LHBT.

RESULTS

The dominant arm LHBT cross-sectional area was significantly smaller than the nondominant arm (9 mm² vs. 10 mm²; P = .011), whereas the dominant arm LHBT echogenicity was significantly higher than the nondominant arm (65 optical density vs. 59 optical density; P = .002). Pitchers with more bicipital groove rotational adaptation (more retroversion) had significantly more LHBT echogenicity adaptation compared with pitchers with less bicipital groove rotational adaptation (12 vs. 2; P = .023).

CONCLUSION

There are significant bilateral differences in the LHBT of professional baseball pitchers. An adaptation in bony rotation was associated with a larger bilateral difference in LHBT echogenicity but was not related to bilateral differences in LHBT area or circularity. Therefore, the bilateral difference in echogenicity is impacted by bony morphology, whereas the bilateral difference in cross-sectional area may be independent of bony morphology in this healthy population.

ICON 2020-International Scientific Tendinopathy Symposium Consensus: A Systematic Review of Outcome Measures Reported in Clinical Trials of Achilles Tendinopathy

BACKGROUND

Nine core domains for tendinopathy have been identified. For Achilles tendinopathy there is large variation in outcome measures used, and how these fit into the core domains has not been investigated.

OBJECTIVE

To identify all available outcome measures outcome measures used to assess the clinical phenotype of Achilles tendinopathy in prospective studies and to map the outcomes measures into predefined health-related core domains.

DESIGN

Systematic review.

DATA SOURCES

Embase, MEDLINE (Ovid), Web of Science, CINAHL, The Cochrane Library, SPORTDiscus and Google Scholar.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Clinical diagnosis of Achilles tendinopathy, sample size ≥ ten participants, age ≥ 16 years, and the study design was a randomized or non-randomized clinical trial, observational cohort, single-arm intervention, or case series.

RESULTS

9376 studies were initially screened and 307 studies were finally included, totaling 13,248 participants. There were 233 (177 core domain) different outcome measures identified across all domains. For each core domain outcome measures were identified, with a range between 8 and 35 unique outcome measures utilized for each domain. The proportion of studies that included outcomes for predefined core domains ranged from 4% for the psychological factors domain to 72% for the disability domain.

CONCLUSION

233 unique outcome measures for Achilles tendinopathy were identified. Most frequently, outcome measures were used within the disability domain. Outcome measures assessing psychological factors were scarcely used. The next step in developing a core outcome set for Achilles tendinopathy is to engage patients, clinicians and researchers to reach consensus on key outcomes measures.

PROSPERO REGISTRATION

CRD42020156763.

Insertional Achilles Tendinopathy: Analysis of 166 Procedures and Return to Activity

The surgical procedure for Insertional Achilles tendinopathy (IAT) varies widely with no consensus as to approach and documenting return to activity (RTA). This study presents outcomes of surgery for IAT by a single surgeon, documenting activity level and return to activity. From January 2001 through January 2018, 166 procedures were reviewed. Surgery included debridement of the Achilles insertion, resection of the superior calcaneus and bursa, and re-attachment with suture anchors. There were 110 males and 56 females. The majority of patients in the entire cohort were runners (n = 54). The average age of the cohort was 50.3 ± 12.1 years (range 20-80). Average follow-up was 114.0 ± 63.5 months (range 6-222 months). Average RTA for males and females were 6.43 months and 7.22 months, (p = .2), respectively. There was no difference in RTA between patients who had calcific tendinosis (n = 84) and noncalcific tendinosis (n = 82). Complications were 2 infections, 2 DVTs, and 17 deep suture reactions with a total complication rate of 12.6%; there were no re-ruptures postoperatively. There was no significant difference in number of complications between absorbable and nonabsorbable suture in the anchors (p = .41). The average RM score was 1.5 ± 0.7. The RM scores were better for males (p = .002), but there were no differences in RTA or complications between sexes. Overall, 95.8% of the procedures resulted in improved outcome and ability to return to activity including sports. This retrospective investigation shows surgical intervention for IAT yields good results with an average return to activity including sports in approximately 7 months.

Effect of knee joint angle on individual hamstrings morphology quantified using free-hand 3D ultrasonography

Exercise responses and injury rates differ between individual hamstrings and this may be linked with their morphology. The aim of this study was to compare muscle length and tendon dimensions between the individual hamstrings at two knee joint angles using free hand three-dimensional ultrasound (3D US). Muscle-tendon length and distal tendon cross-sectional area (CSA), volume, length and echogenicity of biceps femoris long (BFlh) and short (BFsh) head, semimembranosus (SM) and semitendinosus (ST) of 16 individuals were measured using free-hand 3D US at 0° (full extension) and 45° of knee flexion. ST showed the greatest length than all muscles and BFsh the lowest (p < 0.05). No difference was observed between SM and BFlh length (p > 0.05). Of the four muscles, ST tendon was longer, with less volume and CSA but greater echogenicity than the other tendons. In contrast, SM and BFlh showed shorter tendons and lower echogenicity but a greater volume and CSA than ST (p < 0.05). Muscle and tendon lengthened from 45° to 0° knee flexion angle (p < 0.05) but this change was not statistically different between individual hamstrings (p > 0.05). Freehand 3D US indicated that hamstring muscle length and distal tendon dimensions differ between individual hamstrings. All muscles and tendons lengthened as the knee was extended but this change was similar for all individual hamstrings.

The Impact of the Degree of Kinesiophobia on Recovery in Patients With Achilles Tendinopathy

OBJECTIVE

Kinesiophobia has been proposed to influence recovery in individuals with Achilles tendinopathy. However, whether there are differences in outcomes in individuals with different levels of kinesiophobia is unknown. The purpose of this study was to compare the characteristics of patients at baseline and recovery over time in individuals with Achilles tendinopathy and various levels of kinesiophobia.

METHODS

This study was a secondary analysis of a prospective observational cohort study of 59 individuals with Achilles tendinopathy. The participants were divided into 3 groups on the basis of scores on the Tampa Scale for Kinesiophobia (TSK) (those with low TSK scores [≤33; low TSK group], those with medium TSK scores [34-41; medium TSK group], and those with high TSK scores [≥42; high TSK group]). All participants were evaluated with self-reported outcomes, clinical evaluation, tendon morphology, viscoelastic property measurements, and a calf muscle endurance test at baseline, 6 months, and 12 months. No treatment was provided throughout the study period.

RESULTS

There were 16 participants (8 women) in the low TSK group (age = 51.9 [SD = 15.3] years, body mass index [BMI] = 24.3 [22.3-25.4]), 28 participants (13 women) in the medium TSK group (age = 52.7 [SD = 15.2] years, BMI = 26.4 [22.5-30.8]), and 15 participants (8 women) in the high TSK group (age = 61.1 [SD = 11.1] years, BMI = 28.1 [25.2-33.6]). Among the groups at baseline, the high TSK group had significantly greater BMI and symptom severity and lower quality of life. All groups showed significant improvement over time for all outcomes except tendon viscoelastic properties and tendon thickening when there was an adjustment for baseline BMI. The high and medium TSK groups saw decreases in kinesiophobia at 6 months, but there was no change for the low TSK group.

CONCLUSION

Despite the high TSK group having the highest BMI and the worse symptom severity and quality of life at baseline, members of this group showed improvements in all of the outcome domains similar to those of the other groups over 12 months.

IMPACT

Evaluating the degree of kinesiophobia in individuals with Achilles tendinopathy might be of benefit for understanding how they are affected by the injury. However, the degree of kinesiophobia at baseline does not seem to affect recovery; this finding could be due to the patients receiving education about the injury and expectations of recovery.

The Diagnostic Significance of Ultrasonographic Measurement of the Achilles Tendon Thickness for the Insertional Achilles Tendinopathy in Patients with Heel Pain

No consensus exists concerning the diagnostic role or cutoff value of the Achilles tendon thickness on ultrasonography (US) for the diagnosis of insertional Achilles tendinopathy. This study sought to assess the diagnostic utility of US measurement of the thickness and echogenicity of the Achilles tendon for the insertional Achilles tendinopathy in patients with heel pain, and to compare the results with those of the plantar fascia for the plantar fasciitis. We conducted US examinations in consecutive patients who presented with unilateral or bilateral heel pain at the foot clinic of a single tertiary hospital from February 2016 to December 2020. Each US evaluation assessed the thickness and echogenicity&nbsp;of the insertion area of the Achilles tendon and plantar fascia. We retrospectively compared these parameters between patients with insertional Achilles tendinopathy or plantar fasciitis and normal controls and analyzed the diagnostic utility of these parameters. Based on clinical diagnosis, 44 feet were diagnosed with insertional Achilles tendinopathy, 109 feet were diagnosed with plantar fasciitis, and 32 feet were classified as normal. There was a significant difference in the thickness of the plantar fascia between the plantar fasciitis and normal control groups (p = 0.032). There was also a significant difference in the echogenicity of the plantar fascia between the plantar fasciitis and normal groups (p < 0.001). However, there was no significant difference in the thickness of the insertional area of the Achilles tendon between the insertional Achilles tendinopathy and normal groups (p = 0.132). There was a significant difference in the echogenicity of the insertional area of the Achilles tendon between the insertional Achilles tendinopathy and normal groups (p < 0.001). US measurement of the thickness of the insertional area of the Achilles tendon might not reflect the clinical status of insertional Achilles tendinopathy, unlike that of plantar fasciitis.

The correlations between dimensions of the normal tendon and tendinopathy changed Achilles tendon in routine magnetic resonance imaging

This comparative study aimed to investigate how tendinopathy-related lesions change correlations in the dimensions of the Achilles tendon. Our experimental group included 74 patients. The mean age was 52.9 ± 10.4 years. The control group included 81 patients with a mean age was 35.2 ± 13.6 years, p < .001. The most significant difference in correlation was the thickness of the tendon and the midportion's width, which was more significant in the tendinopathy (r = .49 vs. r = .01, p < .001). The correlation was positive between width and length of the insertion but negative in normal tendons (r = .21 vs. r = − .23, p < .001). The correlation was between the midportions width in tendinopathy and the tendon's length but negative in the normal tendon (r = .16 vs. r = − .23, p < .001). The average thickness of the midportion in tendinopathy was 11.2 ± 3.3 mm, and 4.9 ± 0.5 mm in the control group, p < .001. The average width of the midportion and insertion was more extensive in the experimental group, 17.2 ± 3.1 mm vs. 14.7 ± 1.8 mm for the midportion and 31.0 ± 3.9 mm vs. 25.7 ± 3.0 mm for insertion, respectively, p < .001. The tendon's average length was longer in tendinopathy (83.5 ± 19.3 mm vs. 61.5 ± 14.4 mm, p < .001). The dimensions correlations in normal Achilles tendon and tendinopathic tendon differ significantly.

Quantitative Analysis of Patellar Tendon After Total Knee Arthroplasty Using Echo Intensity: A Nonrandomized Controlled Trial of Alpine Skiing

BACKGROUND

Despite the knee extensor weakness, less attention has been paid to the evaluation of patellar tendon after total knee arthroplasty (TKA). We previously observed patellar tendon hypertrophy after TKA. The purpose of this study is to reanalyze these ultrasound data to detect whether brightness mode ultrasound imaging reflects pathological changes of the patellar tendon after TKA.

METHODS

Twenty-eight participants with post unilateral TKA were assigned to an intervention group or control group. The intervention group underwent a 12-week skiing program. Patellar tendon mechanical properties were obtained by combining isometric dynamometry, ultrasound imaging, and electromyography in operated knee and nonoperated knee. Luminosity ratio (LR) was measured using echo intensity in a relaxed and maximally loaded phase.

RESULTS

Baseline comparisons revealed significant effects of the surgical side (P < .001) and loading phase (P = .017), but no interaction between leg and phase (P < .149). LR of the operated knee was significantly lower than LR of the nonoperated knee in relaxed (P < .001) and maximally loaded phases (P = .003). In addition, there was a significant correlation between LR of maximum phase and isometric knee extension torque (r² = 0.156, P = .038). However, LR was not related to patellar tendon stiffness, Young's modulus, or strain. There was a significant time effect in knee extension torque, but no time effects on LR and tendon force.

CONCLUSION

Patellar tendon LR is decreased along with degenerative change after TKA. Ultrasound imaging provides a promising metric to acquire in vivo patellar tendon pathological assessment after TKA.

Tensile mechanical changes in the Achilles tendon due to Insertional Achilles tendinopathy

Insertional Achilles tendinopathy (IAT) is a painful condition that is challenging to treat non-operatively. Although previous studies have characterized the gross histological features, in vivo strain patterns and transverse compressive mechanical properties of tissue affected by IAT, it is not known how IAT impacts the tensile mechanical properties of the Achilles tendon insertion along the axial/longitudinal direction (i.e., along the predominant direction of loading). To address this knowledge gap, the objectives of this study were to 1) apply ex vivo mechanical testing, nonlinear elastic analysis and quasilinear viscoelastic (QLV) analysis to compare the axial tensile mechanical properties of the Achilles tendon insertion in individuals with and without IAT; and 2) use biochemical analysis and second harmonic generation (SHG) imaging to assess structural and compositional changes induced by IAT in order to help explain IAT-associated tensile mechanical changes. Tissue from the Achilles tendon insertion was acquired from healthy donors and from patients undergoing debridement surgery for IAT. Tissue specimens were mechanically tested using a uniaxial tensile (stress relaxation) test applied in the axial direction. A subset of the donor specimens was used for SHG imaging and biochemical analysis. Linear and non-linear elastic analyses of the stress relaxation tests showed no significant tensile mechanical changes in IAT specimens compared to healthy controls. However, SHG analysis showed that fibrillar collagen was significantly more disorganized in IAT tissue as compared with healthy controls, and biochemical analysis showed that sulfated glycosaminoglycan (sGAG) content and water content were higher in IAT specimens. Collectively, these findings suggest that conservative interventions for IAT should target restoration of ultrastructural organization, reduced GAG content, and reduced resistance to transverse compressive strain.

Quantitative Ultrasound Imaging Differences in Multifidus and Thoracolumbar Fasciae between Athletes with and without Chronic Lumbopelvic Pain: A Case-Control Study

New trends in ultrasound imaging are focused on exploration of morphology and muscle quality. The main goal of the study was to evaluate the first-order descriptor and echostructure of lumbar multifidus at the L4 vertebral level in athletes with and without chronic lumbopelvic pain (CLPP). A case-control study was performed in 15 semiprofessional athletes with CLPP and 15 without (healthy athletes). Lumbar multifidus echointensity and echovariation were measured for muscle quality assessment. Echostructure was used to evaluate lumbar multifidus cross-sectional area (CSA) at resting and during muscle contraction, respective differences during both phases (CSA^Dif.), activation patterns, and thoracolumbar fasciae morphology and thickness. Significant differences with a large effect size were observed in quantitative data from CLPP and healthy athletes for left lumbar multifidus CSA^Dif. and thoracolumbar fasciae morphology. Categorical data showed statistically significant differences with a small-to-moderate effect size for lumbar multifidus activation pattern and thoracolumbar fasciae morphology. Athletes with CLPP showed a reduced CSA difference between lumbar multifidus contraction and at resting and higher disorganization of thoracolumbar fasciae morphology compared to healthy athletes. These findings suggest the importance of dynamic exploration of the lumbar region and connective tissue in sports performance and injury prevention.

Mechanical and Material Tendon Properties in Patients With Proximal Patellar Tendinopathy

Introduction

The effect of chronic patellar tendinopathy on tissue function and integrity is currently unclear and underinvestigated. The aim of this cohort comparison was to examine morphological, material, and mechanical properties of the patellar tendon and to extend earlier findings by measuring the ability to store and return elastic energy in symptomatic tendons.

Methods

Seventeen patients with chronic (>3 months, VISA-P < 80), inferior pole patellar tendinopathy (24 ± 4 years; male = 12, female = 5) were carefully matched to controls (25 ± 3 years) for training status, pattern, and history of loading of the patellar tendon. Individual knee extension force, patellar tendon stiffness, stress, strain, Young’s modulus, hysteresis, and energy storage capacity, were obtained with combined dynamometry, ultrasonography, magnetic resonance imaging, and electromyography.

Results

Anthropometric parameters did not differ between groups. VISA-P scores ranged from 28 to 78 points, and symptoms had lasted from 10 to 120 months before testing. Tendon proximal cross-sectional area was 61% larger in the patellar tendinopathy group than in the control group. There were no differences between groups in maximal voluntary isometric knee extension torque (p = 0.216; d < −0.31) nor in tensile tendon force produced during isometric ramp contractions (p = 0.185; d < −0.34). Similarly, tendon strain (p = 0.634; d < 0.12), hysteresis (p = 0.461; d < 0.18), and strain energy storage (p = 0.656; d < 0.36) did not differ between groups. However, patellar tendon stiffness (−19%; p = 0.007; d < −0.74), stress (−27%; p< 0.002; d < −0.90) and Young’s modulus (−32%; p = 0.001; d < −0.94) were significantly lower in tendinopathic patients compared to healthy controls.

Discussion

In this study, we observed lower stiffness in affected tendons. However, despite the substantial structural and histological changes occurring with tendinopathy, the tendon capacity to store and dissipate energy did not differ significantly.

Tendon morphological changes after a prolonged ski race can be detected by ultrasound echo intensity

BACKGROUND

Ultrasound imaging techniques have been used to assess the characteristics of skeletal muscles and tendons. Such techniques (gray scale analysis) allow qualitative evaluation and have been used recently to assess the internal structure of muscles and tendons by computer-aided gray scale analysis. We hypothesized that changes in the internal structure of the Achilles and patellar tendons after a ski mountaineering race competition could be detected with ultrasound.

METHODS

Twenty athletes were recruited during the 19th Millet Tour du Rutor extreme, a three-day ski mountaineering competition. Ultrasound measurements of the Achilles and patellar tendons were carried out before the first race and immediately after each of the three competition days. Tendon thickness, cross-sectional area (CSA), and ultrasound gray scale analysis were calculated.

RESULTS

Significant differences (p < 0.05) were observed between the pre- and post-race measurements for the Achilles tendon thickness and CSA, while no significant differences were noted for the patellar tendon thickness and CSA. However, gray scale analysis of both the Achilles and patellar tendons showed significantly higher post-race values, than the pre-race values (p < 0.05).

CONCLUSIONS

Achilles and patellar tendons of healthy athletes are highly responsive to an acute increase in mechanical load. Those changes can be detected from classical (thickness and CSA) and innovative (gray scale) ultrasound-based parameters.

TRIAL REGISTRATION

This study was approved by the Azienda USL Valle d'Aosta Ethics Committee (protocol no. 23/03/2018.0026243.I).

Local Anesthetic Injection Resolves Movement Pain, Motor Dysfunction, and Pain Catastrophizing in Individuals With Chronic Achilles Tendinopathy: A Nonrandomized Clinical Trial

OBJECTIVES

Peripherally directed treatments (targeted exercise, surgery) can reduce, but not fully eliminate, pain for up to 40% of patients with Achilles tendinopathy. The objectives of the present study were (1) to identify indicators of altered central processing in participants with Achilles tendinopathy compared to controls, and (2) to determine which indicators of altered central processing would persist after a local anesthetic injection in patients with Achilles tendinopathy.

DESIGN

Mechanistic clinical trial.

METHODS

Forty-six adults (23 with chronic Achilles tendinopathy, 23 matched controls) repeated (1) a movement-evoked pain rating, (2) motor performance assessment, (3) pain psychology questionnaires, and (4) quantitative sensory testing. Participants with Achilles tendinopathy received a local anesthetic injection before repeat testing and controls did not. Mixed-effects analyses of variance examined the effects of group, time, and group by time.

RESULTS

The Achilles tendinopathy group had movement-evoked pain, motor dysfunction, and higher pain psychological factors (pain catastrophizing, kinesiophobia) compared to controls (P<.05). The Achilles tendinopathy group did not have indicators of nociplastic pain with quantitative sensory testing (P>.05). In those with Achilles tendinopathy, local anesthetic injection eliminated pain and normalized the observed deficits in heel-raise performance and pain catastrophizing (group-by-time effect, P<.01), but not in kinesiophobia (P = .45). Injection did not affect measures of nociplastic pain (P>.05).

CONCLUSION

People with Achilles tendinopathy had elevated pain psychological factors and motor dysfunction but no signs of nociplastic pain with quantitative sensory testing. Removal of nociceptive input normalized movement-evoked pain and some indicators of altered central processing (motor dysfunction, pain catastrophizing), but not kinesiophobia. J Orthop Sports Phys Ther 2020;50(6):334-343. Epub 29 Apr 2020. doi:10.2519/jospt.2020.9242.

Ultrasound imaging evaluation of structural and textural features in asymptomatic achilles tendons in pre-professional dancers: A cross-sectional study

OBJECTIVE

To evaluate performance descriptors, sociodemographics variables and tendon echogenicity of asymptomatic Achilles tendons and to compare the echotexture from different classification subgroups.

DESIGN

A prospective, randomized cross-sectional study was carried out.

SETTING

laboratory of university.

PARTICIPANTS

Forty-two Achilles tendons (AT) were recruited from pre-professional dancers. Based on the echogenicity pattern, the sample was divided into two groups (n = 21, Heterogeneous group; n = 21, Homogeneous group).

MAIN OUTOCOME MEASURES

Ultrasound images and ImageJ measurements were performed to evaluate thickness (AT-TH), echointensity (EI) and echovariation (EV), in addition to a balance and endurance test were measured as performance parameter.

RESULTS

EI (p = 0.001) and EV (p = 0.001) reported statistically significant differences between groups. AT-TH, endurance test, balance test, years of dance, training hours per week and average pointe hours per week did not showed differences between groups. A multivariate prediction model between groups and the echotexture variables (EI (R² = 0.569; EV (R² = 0.341)) were determined.

CONCLUSION

Asymptomatic AT of heterogeneous group showed a lower EI and a higher EV compared to homogeneous group. Tendon echogenicity did not interact with performance variables.

Reliability of a two-probe ultrasound imaging procedure to measure strain in the Achilles tendon

Background

Alteration in the strain properties of the Achilles tendon may lead to adaptations such as pathological stiffening. Stiff tendons have reduced adaptive ability, which may increase the risk for developing tendinopathy. Strain can be measured using musculoskeletal ultrasound imaging. A two-probe ultrasound procedure may reduce the measurement error associated with a one-probe procedure. However, the reliability of the two-probe procedure has not been established. This study aimed to determine the within-session intra- and inter-rater reliability and between-session reliability of a two-probe ultrasound procedure to measure Achilles tendon strain.

Methods

Participants were 29 healthy individuals (19 females, 10 males; mean age 33.6 years). Achilles tendon images were acquired with a two-probe ultrasound procedure as the ankle moved through a standardised range of motion (20° plantarflexion to 10° dorsiflexion). Both probes were positioned longitudinally, one over the musculotendinous junction and the second over the calcaneal insertion of the Achilles tendon. Repeat measurements were taken for all participants at the initial study visit, and for 10 participants in a second measurement session 4 weeks later. Strain measures were calculated from pre-captured images using Motion Analysis 2014v1 software by two independent raters. Within-session intra- and inter-rater reliability and between-session intra-rater reliability were calculated using intraclass correlation coefficients (ICC) with 95% confidence intervals. The standard error of measurement was also calculated.

Results

The two-probe procedure to measure Achilles tendon strain showed excellent within-session intra-rater (ICC = 0.84, p < 0.001) and inter-rater reliability (ICC = 0.88, p = 0.003), but poor between-session intra-rater reliability (ICC = 0.18, p = 0.397).

Conclusion

The two-probe procedure to measure Achilles tendon strain is reliable for repeated measurements on the same day. However, measurement error increased when strain was measured on different days, which may be attributable to a combination of examiner error and participant factors. Measurement of Achilles tendon strain offers an additional tool for evaluating the tendon's mechanical characteristics. The ability to reliably quantify strain may allow clinicians to identify those at risk for Achilles tendinopathy and formulate more effective management plans.

Altered Strength Profile in Achilles Tendinopathy: A Systematic Review and Meta-Analysis

BACKGROUND

Persistent strength deficits secondary to Achilles tendinopathy (AT) have been postulated to account for difficulty engaging in tendon-loading movements, such as running and jumping, and may contribute to the increased risk of recurrence. To date, little consensus exists on the presence of strength deficits in AT. Consequently, researchers are uncertain about the appropriate methods of assessment that may inform rehabilitation in clinical practice.

OBJECTIVE

To evaluate and synthesize the literature investigating plantar-flexion (PF) strength in individuals with AT.

STUDY SELECTION

Two independent reviewers searched 9 electronic databases using an agreed-upon set of key words.

DATA EXTRACTION

Data were extracted from studies comparing strength measures (maximal, reactive, and explosive strength) between individuals with AT and healthy control participants or between the injured and uninjured sides of people with AT. The Critical Appraisal Skills Programme Case-Control Study Checklist was used to assess the risk of bias for the included studies.

DATA SYNTHESIS

A total of 19 studies were eligible. Pooled meta-analyses for isokinetic dynamometry demonstrated reductions in maximal strength (concentric PF peak torque [PT] slow [Hedges g = 0.52, 44% deficit], concentric PF PT fast [Hedges g = 0.61, 38% deficit], and eccentric PF PT slow [Hedges g = 0.26, 18% deficit]). Reactive strength, particularly during hopping, was also reduced (Hedges g range = 0.32-2.61, 16%-35% deficit). For explosive strength, reductions in the rate of force development (Hedges g range = 0.31-1.73, 10%-21% deficit) were observed, whereas the findings for ground reaction force varied but were not consistently altered.

CONCLUSIONS

Individuals with AT demonstrated strength deficits compared with the uninjured side or with asymptomatic control participants. Deficits were reported across the strength spectrum for maximal, reactive, and explosive strength. Clinicians and researchers may need to adapt their assessment of Achilles tendon function, which may ultimately help to optimize rehabilitation outcomes.

Relationship between the architecture and function of ankle plantar flexors with Achilles tendon morphology in ballet dancers

Achilles tendinopathy is the most frequent foot overuse injury in ballet dancers and knowledge of clinically modifiable factors related to tendon structure in a population at risk, such as ballet dancers, would be important for the development of preventive programs. Therefore, the present study aimed to assess relationships of gastrocnemius muscle architecture and ankle plantar flexors function with Achilles tendon morphology in ballet dancers. Fifty-four measures from 27 ballet dancers were collected. Tendon morphology (thickness, echogenicity, hypoechoic areas and neovascularisation) and muscle architecture (thickness, pennation angle and fascicle length) were evaluated using ultrasonography; ankle plantar flexors torque was evaluated using hand-held dynamometry, flexibility was evaluated in maximal weight-bearing ankle dorsiflexion position using inclinometer, and endurance was evaluated using the heel rise test. Ankle plantar flexors torque and medial gastrocnemius muscle architecture (thickness, pennation angle and fascicle length) are associated with Achilles tendon thickness in ballet dancers (r² = 0.24, p = 0.008). Ankle plantar flexors torque and medial gastrocnemius muscle fascicle length are also associated with the echogenicity of the Achilles tendon (r² = 0.13, p = 0.03). These findings call attention to the potential importance of ankle plantar flexors muscle force in healthy ballet dancers for the prevention of alterations in Achilles tendon structure.

Plantarflexor strength and endurance deficits associated with mid-portion Achilles tendinopathy: The role of soleus

OBJECTIVES

Determine how the strength and endurance of the plantar flexors are affected by Achilles tendinopathy and whether one muscle is more affected than another.

DESIGN

Case control study.

SETTING

University Laboratory.

PARTICIPANTS

39 Runners with mid-portion Achilles tendinopathy and 38 healthy runners participated in this study.

MAIN OUTCOME MEASURES

Isokinetic dynamometry was completed bilaterally in two knee positions on all subjects to assess the torque and endurance capacity of the plantar flexors.

RESULTS

Subjects with Achilles tendinopathy were statistically weaker (by 26.1Nm Concentric 90°/sec, 14,8Nm Concentric 225°/sec and 55.5Nm Eccentric 90°/sec for knee extended testing and 17.3Nm, 10.1Nm and 52.3Nm for the flexed knee respectively) than healthy controls at all isokinetic test speeds and contraction modes irrespective of knee position (p value = <0.001). The endurance capacity of the plantar flexors was significantly reduced (Total work done 613.5Nm less) in subjects with Achilles tendinopathy when compared to the healthy controls (p value = <0.001).

CONCLUSIONS

Achilles tendinopathy is associated with large deficits in plantar flexor torque and endurance. The deficits are bilateral in nature and appear to be explained by a greater loss of the soleus force generating capacity rather than the gastrocnemius.

Test-retest reliability of echo intensity parameters in healthy Achilles tendons using a semi-automatic tracing procedure

OBJECTIVE

To evaluate the test-retest reliability of the ultrasound echo intensity parameters on healthy Achilles tendon using a semi-automatic tracing procedure.

MATERIALS AND METHODS

Eighteen healthy volunteers participated. B-mode images were acquired in the transverse plane (mid-tendon; insertion) and used to analyze tendon echogenicity. Grayscale distribution of the pixels within the selected ROIs was represented as a histogram. Descriptive statistics of the grayscale distribution (mean, variance, skewness, kurtosis, and entropy) and parameters from the co-occurrence matrix (contrast, energy, and homogeneity) were calculated.

RESULTS

Reliability of echo intensity parameters of the mid-Achilles tendon ranged from high to very high with an ICC_2.k of 0.94 for echogenicity, 0.87 for variance, 0.80 for skewness, 0.72 for kurtosis, 0.89 for entropy, 0.90 for contrast, 0.91 for energy, and 0.93 for homogeneity, while for tendon insertion they ranged from moderate to high with an ICC_2.k of 0.74 for echogenicity, 0.88 for variance, 0.75 for skewness, 0.55 for kurtosis, 0.87 for entropy, 0.70 for contrast, 0.77 for energy, and 0.56 for homogeneity.

CONCLUSION

Ultrasound echo intensity is a reliable technique to characterize the internal structure of the Achilles tendon.

Insertional achilles tendinopathy associated with altered transverse compressive and axial tensile strain during ankle dorsiflexion

The purposes of this case-control study (N = 20) were to examine the effects of insertional Achilles tendinopathy (IAT) and tendon region on tendon strain in patients with IAT compared to a control group without tendinopathy. An ultrasound transducer was positioned over the Achilles tendon insertion during dorsiflexion tasks, which included standing and partial squat. A non-rigid image registration-based algorithm was used to estimate transverse compressive and axial tensile strains of the tendon from radiofrequency ultrasound images, which was segmented into two regions (superficial tendon and deep). For transverse compressive strain, two-way mixed effects ANOVAs demonstrated that there were interaction effects between group and tendon region for both dorsiflexion tasks (Heel lowering, p = 0.004; Partial squat, p = 0.008). For axial tensile strain, the IAT group demonstrated a main effect of lower tensile strain than the control group (Standing, p = 0.001; Partial squat, p = 0.033). There was also a main effect of greater tensile strain in the superficial region of the tendon compared to the deep during standing (p = 0.002), but not during partial squat (p = 0.603). Reduced transverse compressive and axial tensile strains in the IAT group indicate altered mechanical properties specific to the region of IAT pathology. Additionally, patterns of compressive strain are consistent with the theory of calcaneal impingement contributing to IAT pathology. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:910-915, 2017.

Achilles tendon morphology, plantar flexors torque and passive ankle stiffness in spastic hemiparetic stroke survivors

BACKGROUND

The present study compared the Achilles tendon morphological characteristics, plantar flexor toque and passive ankle stiffness between hemiparetic spastic stroke survivors and healthy subjects.

METHODS

The Achilles tendon length was measured at the affected and contralateral limbs of twelve hemiparetic stroke survivors with ankle spasticity and twelve healthy subjects. The ankle was held at three different angles (20° plantar flexion, 0° and maximum dorsiflexion) while an ultrasound system was used to capture images from the Achilles tendon. Active and passive plantar flexor torque production was measured using an isokinetic dynamometer.

FINDINGS

There was no significant difference in tendon length and Achilles tendon complacency between stroke survivors [affected limb: 20.8 (1.59) cm at 0° and 0.11 (0.09) cm/N; contralateral limb: 20.8 (1.7) cm at 0° and 0.12 (0.08) cm/N] and healthy subjects [20 (2.78) cm at 0° and 0.15 (0.1) cm/N]. The contralateral limb was stronger than the affected limb, while healthy participants presented larger active torque in relation to stroke survivors. There was no significant difference in passive ankle stiffness between the affected [0.43 (0.08) N/°] and the contralateral limb [0.40 (0.11) N/°], but affected limb was significantly stiffer than the healthy subjects [0.32 (0.07) N/°].

INTERPRETATION

The larger passive torque and ankle joint stiffness from stroke survivors with similar Achilles tendon length compared to healthy subjects seem to be unrelated to tendon extensibility.

Patients With Insertional Achilles Tendinopathy Exhibit Differences in Ankle Biomechanics as Opposed to Strength and Range of Motion

Study Design Controlled laboratory study; cross-sectional. Background Little is known about ankle range of motion (ROM) and strength among patients with insertional Achilles tendinopathy (IAT) and whether limited ankle ROM and plantar flexor weakness impact IAT symptom severity. Objectives The purposes of the study were (1) to examine whether participants with IAT exhibit limited non-weight-bearing dorsiflexion ROM, reduced plantar flexor strength, and/or altered ankle biomechanics during stair ascent; and (2) to determine which impairments are associated with symptom severity. Methods Participants included 20 patients with unilateral IAT (mean ± SD age, 59 ± 8 years; 55% female) and 20 individuals without tendinopathy (age, 58.2 ± 8.5 years; 55% female). A dynamometer was used to measure non-weight-bearing ROM and isometric plantar flexor strength. Three-dimensional motion analysis was used to quantify ankle biomechanics during stair ascent. End-range dorsiflexion was quantified as the percentage of non-weight-bearing dorsiflexion used during stair ascent. Group differences were compared using 2-way and 1-way analyses of variance. Pearson correlations were used to test for associations among dependent variables and symptom severity. Results Groups differed in ankle biomechanics, but not non-weight-bearing ROM or strength. During stair ascent, the IAT group used greater end-range dorsiflexion (P = .03), less plantar flexion (P = .02), and lower peak ankle plantar flexor power (P = .01) than the control group. Higher end-range dorsiflexion and lower ankle power during stair ascent were associated with greater symptom severity (P<.05). Conclusion Patients with IAT do not experience restrictions in non-weight-bearing dorsiflexion ROM or isometric plantar flexor strength. However, altered ankle biomechanics during stair ascent were linked with greater symptom severity and likely contribute to decreased function. J Orthop Sports Phys Ther 2016;46(12):1051-1060. Epub 29 Oct 2016. doi:10.2519/jospt.2016.6462.

Forefoot and rearfoot contributions to the lunge position in individuals with and without insertional Achilles tendinopathy

BACKGROUND

Clinicians use the lunge position to assess and treat restricted ankle dorsiflexion. However, the individual forefoot and rearfoot contributions to dorsiflexion and the potential for abnormal compensations are unclear. The purposes of this case-control study were to 1) compare single- (representing a clinical lunge position measure) versus multi-segment contributions to dorsiflexion, and 2) determine if differences are present in patients with tendinopathy.

METHODS

32 individuals (16 with insertional Achilles tendinopathy and 16 age- and gender-matched controls) participated. Using three-dimensional motion analysis, the single-segment model was defined as tibial inclination relative to the whole foot. The multi-segment model consisted of rearfoot (tibia relative to calcaneus) and forefoot (1st metatarsal relative to calcaneus) motion. Two-way (kinematic model and group) analyses of variance were used to assess differences in knee bent and straight positions. Associations between models were tested with Pearson correlations.

FINDINGS

Single-segment modeling resulted in ankle DF values 5° greater than multi-segment modeling that isolated rearfoot dorsiflexion for knee bent and straight positions (P<0.01). Compared to controls, the tendinopathy group had 10° less dorsiflexion with the knee bent (P<0.01). For the tendinopathy group, greater dorsiflexion was strongly associated with greater rearfoot (r=0.95, P<0.01) and forefoot (r=0.81, P<0.01) dorsiflexion. For controls, dorsiflexion was strongly associated with rearfoot (r=0.87, P<0.01) but not forefoot dorsiflexion (r=0.23, P=0.39).

INTERPRETATION

Clinically used single-segment models of ankle dorsiflexion overestimate rearfoot dorsiflexion. Participants with insertional Achilles tendinopathy may compensate for restricted and/or painful ankle dorsiflexion by increased lowering of the medial longitudinal arch (forefoot dorsiflexion) with the lunge position.

Utility of Ultrasound for Imaging Osteophytes in Patients With Insertional Achilles Tendinopathy

OBJECTIVES

To examine (1) the validity of ultrasound imaging to measure osteophytes and (2) the association between osteophytes and insertional Achilles tendinopathy (IAT).

DESIGN

Case-control study.

SETTING

Academic medical center.

PARTICIPANTS

Persons with chronic unilateral IAT (n=20; mean age, 58.7±8.3y; 10 [50%] women) and age- and sex-matched controls (n=20; mean age, 57.4±9.8y; 10 [50%] women) participated in this case-control study (N=40).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Symptom severity was assessed using the Foot and Ankle Ability Measure, the Victorian Institute of Sport Assessment-Achilles questionnaire, and the numerical rating scale. Length of osteophytes was measured bilaterally in both groups using ultrasound imaging, as well as on the symptomatic side of the IAT group using radiography. The intraclass correlation coefficient was used to examine the agreement between ultrasound and radiograph measures. McNemar, Wilcoxon signed-rank, and Fisher exact tests were used to compare the frequency and length of osteophytes between sides and groups. Pearson correlation was used to examine the association between osteophyte length and symptom severity.

RESULTS

There was good agreement (intraclass correlation coefficient, ≥.75) between ultrasound and radiograph osteophyte measures. There were no statistically significant differences (P>.05) in the frequency of osteophytes between sides or groups. Osteophytes were larger on the symptomatic side of the IAT group than on the asymptomatic side (P=.01) and on the left side of controls (P=.03). There was no association between osteophyte length and symptom severity.

CONCLUSIONS

Ultrasound imaging is a valid measure of osteophyte length, which is associated with IAT. Although a larger osteophyte indicates tendinopathy, it does not indicate more severe IAT symptoms.