MRI of the Achilles tendon-A comprehensive pictorial review. Part one

Assessment of calf muscle constitution in chronic Achilles tendon disease using Dixon-based MRI

OBJECTIVES

To assess calf muscle constitution in chronic Achilles tendon disease (ATD) using two-point Dixon-based MRI (2pt-MRIDIXON).

MATERIALS AND METHODS

This retrospective study analyzed 91 patients (36 females; 57.0 ± 14.4 years) with midportion or insertional chronic ATD who underwent clinical MRI of the Achilles tendon (AT), including 2pt-MRIDIXON for quantitative assessment of calf muscle fat content (MFC). Additionally, two radiologists qualitatively assessed MFC, AT quality, and co-pathologies. 2pt-MRIDIXON-derived fat fractions (FF) were related to patients' demographics and qualitative imaging findings.

RESULTS

The overall mean FF derived from 2pt-MRIDIXON of the triceps surae muscle was 11.2 ± 9.3%. Comparing midportion and insertional ATD, there was no significant difference regarding fatty muscle infiltration assessed with 2pt-MRIDIXON (P ≥ .47) or qualitative grading (P ≥ .059). More severe AT thickening (11 vs.9 mm, P < .001) and complete tears (29 vs. 9%, P = .025) were significantly more common in midportion ATD, while partial tears were significantly more frequent in insertional ATD (55 vs. 31%, P = .027). Soleus muscle edema was more prevalent in midportion than insertional ATD (40 vs. 9%, P = .002). In contrast, insertional ATD more commonly featured bone marrow edema (61 vs. 2%), Haglund's deformity (67 vs. 0%), and retrocalcaneal bursitis (82 vs. 43%) (P ≤ .002). Significant correlations (P ≤ .001) were demonstrated between FF, AT diameter, age (both in midportion and insertional ATD), and body mass index (in midportion ATD only) (ρ range = 0.53-0.61).

CONCLUSION

In chronic ATD, calf MFC was statistically equivalent (approximately 11%), irrespective of the localization of tendon damage. More severe tendon thickening and complete tears were more common in midportion ATD, and, vice versa, partial AT tears were significantly more frequent in insertional ATD.

Outcomes After Extracorporeal Shockwave Therapy for Chronic Noninsertional Achilles Tendinopathy Compared With Chronic Insertional Achilles Tendinopathy: A Retrospective Review

Background

Extracorporeal shockwave therapy (ESWT) is a noninvasive treatment modality that is used in the treatment of chronic Achilles tendinopathy (AT).

Purposes

To (1) retrospectively assess outcomes after ESWT for both noninsertional AT (NAT) and insertional AT (IAT) at >1-year follow-up and (2) identify potential predictors of outcomes.

Study Design

Cohort study; Level of evidence, 3.

Methods

Chart review was conducted to identify patients who underwent ESWT for AT with a minimum of 1-year follow-up. Data collected and assessed included patient demographic characteristics, pathological characteristics including the location of AT (NAT or IAT), presence of a Haglund deformity, and severity of tendon degeneration on magnetic resonance imaging (MRI), in addition to treatment characteristics including number of sessions and intensity of ESWT. The Victorian Institute of Sports Assessment-Achilles (VISA-A) and visual analog scale (VAS) pain scores were obtained before ESWT, 6 months after ESWT, and at final follow-up. Failures were also recorded, which were defined as no improvement in VISA-A or VAS scores or need for surgical intervention. Linear regression was performed to identify potential predictors of inferior subjective clinical outcomes and failures. Survival analysis was conducted using Kaplan-Meier curves.

Results

The study included 52 patients with IAT and 34 patients with NAT. The mean follow-up in the NAT cohort was 22.3 ± 10.2 months and the mean follow-up in the IAT cohort was 26.8 ± 15.8 months. Improvements in VISA-A and VAS scores were observed in the NAT cohort at 6-month follow-up and at final follow-up (P < .05). Improvements in VISA-A and VAS scores were recorded in the IAT cohort at 6-month follow-up, which subsequently deteriorated at final follow-up. In the NAT cohort, the failure rate at 6-month follow-up was 11.8%, which increased to 29.4% at final follow-up. In the IAT cohort, the failure rate at 6-month follow-up was 32.7%, which increased to 59.6% at final follow-up. Predictors of inferior subjective clinical outcomes and failures in the NAT cohort included pre-ESWT subjective clinical score, male sex, presence of a cardiovascular risk factor, and more severe MRI grading of tendinopathy. Predictors of inferior subjective clinical outcomes and failures in the IAT cohort included pre-ESWT subjective clinical score and more severe MRI grading of tendinopathy.

Conclusion

Superior subjective clinical outcomes together with a lower failure rate were maintained for >1 year in the NAT cohort compared with the IAT cohort, calling into question the long-term benefit of ESWT for patients with IAT.

Insertional Achilles tendinopathy: A radiographic cross-sectional comparison between symptomatic and asymptomatic heel of 71 patients

Purpose

This retrospective study aimed to investigate whether the standard radiographic indicators for Haglund's syndrome are applicable to insertional Achilles tendinopathy.

Methods

Patients who underwent surgery for insertional Achilles tendinopathy in one heel and experienced no pain in the other heel were enrolled in this study. Preoperative calibrated radiographs of the lateral view of the calcaneus were assessed using (1) calcaneal pitch angle, (2) Fowler-Phillip angle, (3) posterior calcaneal angle, (4) Chauveau-Liet angle, (5) X/Y ratio, (6) Haglund's deformity height, (7) Haglund's deformity peak angle, (8) calcification length, (9) calcification width, (10) parallel pitch test, and (11) presence of free body. The Wilcoxon signed rank test and McNemar's test were used for statistical analyses.

Results

Seventy-one patients (52 males; mean age, 57.2; mean body mass index, 27.1) were included. Mean values for each index in the symptomatic and asymptomatic heels were as follows, respectively: (1) 23.5, 23.0 (p = 0.30); (2) 58.9, 57.8 (p < 0.05); (3) 7.6, 9.2 (p < 0.05); (4) 15.8, 13.9 (p < 0.05); (5) 2.8, 2.8 (p = 0.87); (6) 5.4, 5.0 (p < 0.05); (7) 99.6, 99.0 (p = 0.44); (8) 10.5, 7.6 (p < 0.001); and (9) 5.1, 4.4 (p < 0.05). The sensitivity, specificity, and area under curve of significant indicators were as follows, respectively: (2) 0.78, 0.37, 0.55; (3) 0.45, 0.72, 0.58; (4) 0.63, 0.54, 0.57; (6) 0.45, 0.69, 0.59; (8) 0.48, 0.80, 0.66; and (9) 0.63, 0.54, 0.59. The presence of free body also showed a significant difference between both heels (p < 0.05).

Conclusion

Some radiographic indicators for Haglund's syndrome are applicable to the diagnosis of insertional Achilles tendinopathy. A comparison of the parameters of Haglund's syndrome with those of insertional Achilles tendinopathy may illuminate the etiology and pathology of insertional Achilles tendinopathy and lead to novel treatments.

Assessment of Calcaneal Spongy Bone Magnetic Resonance Characteristics in Women: A Comparison between Measures Obtained at 0.3 T, 1.5 T, and 3.0 T

BACKGROUND

There is a growing interest in bone tissue MRI and an even greater interest in using low-cost MR scanners. However, the characteristics of bone MRI remain to be fully defined, especially at low field strength. This study aimed to characterize the signal-to-noise ratio (SNR), T2, and T2* in spongy bone at 0.3 T, 1.5 T, and 3.0 T. Furthermore, relaxation times were characterized as a function of bone-marrow lipid/water ratio content and trabecular bone density.

METHODS

Thirty-two women in total underwent an MR-imaging investigation of the calcaneus at 0.3 T, 1.5 T, and 3.0 T. MR-spectroscopy was performed at 3.0 T to assess the fat/water ratio. SNR, T2, and T2* were quantified in distinct calcaneal regions (ST, TC, and CC). ANOVA and Pearson correlation statistics were used.

RESULTS

SNR increase depends on the magnetic field strength, acquisition sequence, and calcaneal location. T2* was different at 3.0 T and 1.5 T in ST, TC, and CC. Relaxation times decrease as much as the magnetic field strength increases. The significant linear correlation between relaxation times and fat/water found in healthy young is lost in osteoporotic subjects.

CONCLUSION

The results have implications for the possible use of relaxation vs. lipid/water marrow content for bone quality assessment and the development of quantitative MRI diagnostics at low field strength.

An in-depth study on the magnetic resonance imaging characteristics of tendon rupture in sports injuries and its correlation with patients' clinical symptoms

Muscle injuries, such as Achilles and quadriceps tendon ruptures, pose a significant challenge in elite sports, accounting for more than 30% of all sports-related injuries. Our primary goal is to investigate the MR imaging characteristics of tendon rupture in sports injuries and their relationship with patients' clinical symptoms. In our retrospective study at Zhejiang University of Traditional Chinese Medicine's Second Affiliated Hospital (Zhejiang Xinhua Hospital), we compared the clinical presentation and MRI results of 106 patients with isolated AT and QT ruptures. In the AT, the enthesis was identified as a common site of bony avulsions (30.2%). In contrast, insertional ruptures were more common in the gastrocnemius heads (69.8% and 66.0%). The low frequency of mid-substance tears (13.2% to 20.8%) demonstrated the central tendon region's inherent tensile strength. The ruptured musculotendinous junctions affected the soleus (20.8%). In QT, bony avulsions play a minor role (5.1% to 11.3%). The patella was the primary site of tears (42.2% - 45.3%), with the Vastus intermedius favoring proximal tears (58.5%). Our examination of AT and QT ruptures across sub-components sheds light on their distinct patterns and the implications for clinical practice in terms of precise diagnosis, personalized treatment, and, ultimately, better patient outcomes for these debilitating injuries.

Is a Preoperative MRI Scan Necessary for Acute Achilles Tendon Rupture?

BACKGROUND

Different treatment methods have been developed for acute Achilles tendon rupture (ATR), including conservative treatment, minimally invasive or transdermal surgery, and open surgery, and there is no consensus about which method is superior. It is important to clarify the presence of Achilles tendon (AT) degeneration, the rupture site, and the rupture shape before surgery to determine whether minimally invasive or open surgery should be selected, thereby reducing the re-rupture rate following acute ATR. The aim of this study was to investigate the diagnostic value of MRI in identifying the presence of AT degeneration, the rupture site, and the rupture shape for acute closed ATR.

METHODS

From January 2016 to December 2019, patients with acute closed ATR who had undergone repair surgery were retrospectively enrolled. All patients received MRI examination, and the distance between the insertion site and broken end and the rupture shape (types I, II, and III) were independently determined by two observers. Then, the stump of the AT was exposed during the operation. The rupture site and rupture shape were recorded and compared and analyzed with the MRI results. Consistency analyses (using Cohen's kappa coefficient or intraclass correlation coefficient-ICC) and calculation of diagnostic performance indexes were, respectively, conducted to evaluate the diagnostic value of the MRI.

RESULTS

This study included 47 consecutive patients with acute ATR, with an average age of 38.4 years. Among them, 40 were male, and seven were female. The intraoperative exploration demonstrated a total of 34 (72.3%), 10 (21.3%), and three (6.4%) patients with type I, II, and III ruptures, respectively. The average distance between the insertion site and the proximal broken end measured intraoperatively was 4.07 ± 1.57 cm. High or excellent consistencies were found for ATR classifications (kappa: 0.739-0.770, p < 0.001) and rupture sites (ICC: 0.962-0.979, p < 0.001) between two observers and between observers 1 and 2 and intraoperative findings. Tendinopathy was identified in 22 patients by MRI and confirmed during surgery.

CONCLUSIONS

MRI scanning of acute closed ATR can help determine whether there is degeneration of the AT, as well as the location and shape of the rupture, which can guide the selection of the optimal operation method for orthopedic surgeons. Therefore, it is necessary to take preoperative MRI scans for patients with acute Achilles tendon ruptures.

Ultrasonography-guided Intervention in the Achilles Tendon and Plantar Fascia

Tendinopathy is very common in the foot and ankle. Achilles tendinopathy is a painful overuse injury that often occurs in athletes, especially those who participate in running and jumping sports. Plantar fasciitis is the most frequent cause of plantar pain in the adult heel. Initial treatment of these conditions is conservative. However, in some cases symptoms only improve slowly, and many cases are intractable. When conservative management fails, ultrasonography guided injections are indicated. We discuss the main interventions performed in the foot and ankle for Achilles tendinopathy, retrocalcaneal bursitis, and plantar fasciitis. We describe the different agents that can be used and the various ultrasonography-guided procedures that offer technical and practical information to improve daily clinical practice.

Presurgical Perspectives and Post-treatment Evaluation of Achilles Tendon Injuries

The Achilles is a commonly injured tendon, prone to degeneration and tear. Achilles tendon treatment ranges from conservative management to injections, tenotomy, open versus percutaneous tendon repair, graft reconstruction, and flexor hallucis longus transfer. Interpreting postoperative imaging of the Achilles tendon is a difficult task for many providers. This article clarifies these issues by presenting the imaging findings following standard treatments and depicts expected appearance versus recurrent tear and other complications.

Minimally invasive excision and reconstruction of Achilles tendon xanthoma using free autologous semitendinosus tendon transfer: a surgical technique

BACKGROUND

Tendon xanthomatosis is often associated with familial hypercholesterolemia, but it can also occur in other medical conditions. The Achilles tendon is the most common site of tendon xanthomas. Reconstruction of large defects after the xanthoma excision, can be challenging.

METHODS

We propose a novel technique for Achilles tendon reconstruction with the use of an ipsilateral autologous semitendinosus tendon graft. The technique consists of six steps.

RESULTS

This procedure has a low rate of complications and provides results that are at least comparable with those reported with other surgical approaches.

Validation of a novel magnetic resonance imaging classification and recommended treatment for lateral elbow tendinopathy

BACKGROUND

Lateral epicondylitis is one of the most common upper extremity problems presented to orthopedic surgeons. Despite a rapid and accurate arrival at a diagnosis by clinical examination, there exists no consensus classification for this condition, which hampers clinical approaches for treatment of the disease based on its severity. Thus, the aim of this study was to propose and valiadate a new magnetic resonance imaging (MRI) classification of lateral epicondylitis, staging by tendinosis, the degree of thickness tears of the common extensor tendon (CET) and bone bruise lesion.

METHOD

MRI assessment of the elbow of 75 patients (57 women and 18 men; mean age:51.4 years (range,34-73) from Jan 2014 to Jan 2021 who were diagnosed with lateral epicondylitis were included in the study. MR images were reviewed retrospectively by two independent upper extremities orthopedists and one musculoskeletal radiologist. Inter- and intra-observer reliabilities for the classification were calculated using kappa statistics for the analysis of interrater agreement. Correlation between the stage of the disease and the duration of symptom before MRI was calculated using Kruskal-wallis test.

RESULTS

Various degrees of CET lesions were demonstrated in this population (Stage I-17, IIA-7, IIB-22 and III-29). Intra-observer agreements of MRI staging were substantial to satisfactory. Inter-observer agreements were moderate to substantial. There was no significant correlation between the disease stage and the patient age or the duration of symptom before MRI.

CONCLUSION

Our MRI classification has emerged as one of the most reliable methods to define stages of chronic lateral epicondylitis. At the end, we have suggeted a clearer direction for understanding the disease pathology as well as an appropriate management protocol for each stage of the disease in line with the recent body of literature.