Imaging of calcific tendinopathy: natural history, migration patterns, pitfalls, and management: a review

Extracorporeal Shockwave Therapy for Tendinopathies Around the Hip and Pelvis: A Systematic Review

Background: Tendinopathies affecting the hip and pelvis include proximal hamstring tendinopathy (PHT), gluteal tendinopathy (greater trochanteric pain syndrome [GTPS]), and calcific tendinopathy (CT). Extracorporeal shockwave therapy (ESWT) is a noninvasive treatment described for the management of lower-extremity tendinopathies. Purpose: We sought to synthesize the evidence on ESWT used in the treatment of hip/pelvis tendinopathies, including protocols, outcomes, and safety. Methods: A comprehensive search of PubMed/Medline, EMBASE, and Cochrane Library databases was performed on November 1, 2024, for studies reporting ESWT data for hip/pelvis tendinopathies. Study design, population, and ESWT-related data (protocols, outcomes, and safety) were extracted. Results: Eighteen studies were included; 9 reported on GTPS, 7 on CT, and 5 on PHT. Most ESWT protocols (72% [n = 13]) implemented 3 to 4 weekly sessions and delivered 2000 to 3000 pulses/session (83% [n = 15]). Eleven studies used radial ESWT and 7 used focused ESWT. ESWT significantly improved pain and functional outcomes for GTPS, CT, and PHT in 17 level-I to level-V studies; only 1 level-V study showed no improvement. Six studies showed superior outcomes post-ESWT vs conservative treatment (PHT/GTPS), sham ESWT (GTPS), ultrasound therapy (GTPS/CT), or corticosteroid injection (GTPS). One study showed comparable outcomes between ESWT and eccentric exercise (GTPS). Two studies reported no outcome differences between radial ESWT and "minimal-dose" ESWT (GTPS) or combined ESWT (PHT). All studies assessing pain showed improvement from 0.5 to 27 months post-ESWT. Six of 18 studies reported adverse events, including increased pain and skin irritation (overall rate: 12% [n = 65/557]). Conclusions: The results of this systematic review suggest that ESWT may be safe and effective for hip/pelvis tendinopathies. Future research using validated outcome measures and ESWT parameters will aid in treatment optimization.

Uncommon Presentation of Hip Pain Due to Calcific Tendonitis in the Rectus Femoris

Introduction

Calcific tendonitis is characterized by calcium hydroxyapatite crystal deposition in tendons, leading to inflammation and pain. While predominantly observed in the rotator cuff tendons of the shoulder, its occurrence in the rectus femoris tendon of the hip is exceedingly rare and poses a diagnostic challenge.

Case Report

A 38-year-old female housewife presented with a 1-month history of left hip pain, which was dull, aching, and exacerbated by movements such as standing and walking. High-resolution computed tomography imaging showed calcification at the insertion of the left rectus femoris muscle. A magnetic resonance imaging confirmed the diagnosis, revealing no significant abnormalities in the hip joints or surrounding structures. The patient was diagnosed with calcific tendonitis at the insertion of the left rectus femoris muscle and was managed conservatively with rest, Non-steroidal anti-inflammatory drugs, and physical therapy. Follow-up visits were scheduled to monitor her progress and response to treatment.

Conclusion

This case underscores the importance of thorough clinical and imaging evaluations in diagnosing calcific tendonitis in atypical locations. Conservative treatment proved effective, highlighting the need for tailored management strategies. Future research should focus on elucidating the pathogenesis and optimizing treatment for calcific tendonitis in uncommon sites.

Understanding the effects of mineralization and structure on the mechanical properties of tendon-bone insertion using mesoscale computational modeling

Tendon-bone fibrocartilaginous insertion, or enthesis, is a specialized interfacial region that connects tendon and bone, effectively transferring forces while minimizing stress concentrations. Previous studies have shown that insertion features gradient mineralization and branching fiber structure, which are believed to play critical roles in its excellent function. However, the specific structure-function relationship, particularly the effects of mineralization and structure at the mesoscale fiber level on the properties and function of insertion, remains poorly understood. In this study, we develop mesoscale computational models of the distinct fiber organization at tendon-bone insertions, capturing the branching network from tendon to interface fibers and the different mineralization scales. We specifically analyze three key descriptors: the mineralization scale of interface fibers, the mean, and relative standard deviation of the local branching angles of interface fibers. Tensile test simulations on insertion models with varying mineralization scales of interface fibers and structures are performed to mimic the primary loading condition applied to the insertion. We measure and analyze five representative mechanical properties: Young's modulus, strength, toughness, resilience, and failure strain. Our results reveal that mechanical properties are significantly influenced by the three key descriptors, with tradeoffs observed between mutually exclusive properties. For instance, strength and resilience plateau beyond a certain mineralization scale, while failure strain and Young's modulus exhibit monotonic decreasing and increasing trends, respectively. Consequently, there exists an optimal mineralization scale for toughness due to these tradeoffs. By analyzing the mesoscale deformation and failure mechanisms from simulation trajectories, we identify three fracture regimes closely related to the trends in mechanical properties, supporting the observed tradeoffs. Additionally, we examine in detail the effects of the mean and relative standard deviation of local branching angles on mechanical properties and deformation mechanisms. Overall, our study enhances the fundamental understanding of the composition-structure-function relationships at the tendon-bone insertion, complementing recent experimental studies. The mechanical insights from our work have the potential to guide the future biomimetic design of fibrillar adhesives and interfaces for joining soft and hard materials.

Exploring Metabolic Mechanisms in Calcific Tendinopathy and Shoulder Arthrofibrosis: Insights and Therapeutic Implications

Rotator cuff calcific tendinopathy and arthrofibrosis of the shoulder (adhesive capsulitis) are debilitating musculoskeletal disorders that significantly impact joint function and impair quality of life. Despite its high prevalence and common clinical presentation, the metabolic mechanisms underlying these conditions characterized by pain, and reduced mobility, remain poorly understood. This review aims to elucidate the role of metabolic processes implicated in the pathogenesis of calcific tendinopathy and shoulder arthrofibrosis. We will be focusing on the mechanistic role of how these processes contribute to disease progression and can direct potential therapeutic targets. Calcific tendinopathy is marked by aberrant calcium deposition within tendons, influenced by disrupted calcium and phosphate homeostasis, and altered cellular responses. Key molecular pathways, including bone morphogenetic proteins (BMPs), Wnt signaling, and transforming growth factor-beta (TGF-β), play crucial roles in the pathophysiology of calcification, calcium imbalance, and muscle fibrosis. In contrast, shoulder arthrofibrosis involves excessive collagen deposition and fibrosis within the shoulder joint capsule, driven by metabolic dysregulation and inflammation. The TGF-β signaling pathway and inflammatory cytokines, such as interleukin-6 (IL-6), are central to the fibrotic response. A comparative analysis reveals both shared and distinct metabolic pathways between these conditions, highlighting the interplay between inflammation, cellular metabolism, extracellular matrix remodeling, calcific deposition, and calcium migration to the glenohumeral joints, resulting in adhesive capsulitis, thereby providing insights into their pathophysiology. This review discusses current therapeutic approaches and their limitations, advocating for the development of targeted therapies that address specific metabolic dysregulations. Future therapeutic strategies focus on developing targeted interventions that address the underlying metabolic dysregulation, aiming to improve patient outcomes and advance clinical management. This review offers a comprehensive overview of the metabolic mechanisms involved in calcific tendinopathy and shoulder arthrofibrosis, providing a foundation for future research and therapeutic development.

Can Secondary Adhesive Capsulitis Complicate Calcific Tendinitis of the Rotator Cuff? An Ultrasound Imaging Analysis

BACKGROUND

Adhesive capsulitis (AC) of the glenohumeral joint is a recognized cause of pain associated with both active and passive restricted ranges of movement. AC can be subdivided into primary and secondary forms. Trauma, surgery, immobilization, and diabetes mellitus are the leading well-recognized causes of secondary AC. Calcific tendinitis/tendinitis (CT) of the rotator cuff is considered a possible trigger for AC, as reported in a few previous articles. However, there are no original investigations that assess the frequency and characteristics of this association. The aim of our research was to evaluate the presence of AC in a cohort of patients with a known CT condition of the rotator cuff by an ultrasound (US) examination.

MATERIALS AND METHODS

We prospectively enrolled all the patients admitted at our single institution (October 2022-June 2023) for the preoperative US evaluation of a known CT condition. In these patients, we searched for parameters related to secondary AC. An axillary pouch (AP) thickness equal to or greater than 4 mm (or greater than 60% of the contralateral AP) was considered diagnostic of AC. Moreover, rotator interval (RI) thickness and the presence of effusion within the long-head biceps tendon (LHBT) sheath was also assessed in all patients.

RESULTS

A total of 78 patients (54F, 24M-mean age = 50.0 and range = 31-71 y.o.) were enrolled in the study. In 26 of those patients (26/78-33.3%), US signs of AC were detected. Notably, the mean AP thickness in patients with AC and CT was 3.96 ± 1.37 mm (Group 1) and 2.08 ± 0.40 mm in patients with CT only (Group 2). RI thickness was significantly greater in patients with superimposed AC: 2.54 ± 0.38 mm in Group 1 and 1.81 ± 0.41 mm in Group 2 (p < 0.00001). Moreover, effusion within the LHBT was significantly more frequently detected in patients with AC: 84.61% in Group 1 versus 15.79% in Group 2-p < 0.00001.

CONCLUSION

US signs of AC are found in one-third of patients with CT of the rotator cuff, demonstrating that AC represents a frequent complication that should be routinely evaluated during US investigation to provide more personalized treatment strategies.