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

Calcific tendinopathy is characterized by the deposition of calcium hydroxyapatite crystals in various tendons of the body. Terms like calcium tendinitis, tendinosis, and tendinopathy are used interchangeably. Calcific tendinopathy is a common and well-documented ailment in the literature. Although common, the natural history, etiology, and progression of calcific tendinitis are poorly understood. The treatment options include conservative and interventional measures. However, these measures cannot be applied as a blanket and are often tailored depending on the stage/phase of the disease. Out of the recognized stages of the disease, the resorptive stage causes the utmost symptoms when the calcium is rather soft and unstable. During this stage, the calcium may migrate beyond expected resorption and get deposited in the adjacent tissues contiguous with the calcium focus. The common destinations include bursal migration, intraosseous migration, muscular migration, and other less common migration sites. Such atypical presentations can lead to dilemmas in the diagnosis, prolongation of the diagnostic pathway, unwarranted apprehension, and treatment delay. Radiologists' role in this situation is to correctly recognize the imaging findings of atypical presentations of calcific tendinopathy and prevent unnecessary diagnostic and interventional studies. In this review article, we describe the pathogenic pathway and natural history of calcific tendinopathy from a radiologist's perspective and discuss different migratory patterns of calcium in calcific tendinopathy not only around the shoulder but also in other areas of the body on different imaging modalities. We also show a few examples of mimics and pitfalls on imaging. Finally, we discuss the appropriate management option of this condition.

Gluteus medius calcific tendonitis as a cause of severe anterior hip pain.

Calcific tendinopathy in the gluteus medius is uncommon and sporadically reported. It may be asymptomatic or present with acute or chronic pain. Pain is usually isolated to the lateral hip overlying the gluteal muscles or greater trochanter. We present a rare case of gluteus medius calcific tendonitis as a cause of severe anterior hip pain. Given the atypical local and clinical presentation these can be often misdiagnosed as septic arthritis or fracture which may lead to overtreatment and even unnecessary surgery. This article will detail the clinical presentation, imaging findings, and clinical course following treatment. This will facilitate the clinician in making a timely diagnosis and establishing an effective treatment course.

US-guided percutaneous irrigation of extra-shoulder calcific tendinitis.

OBJECTIVES: To investigate the efficacy and safety of ultrasound-guided percutaneous irrigation of calcific tendinopathy (US-PICT) applied out of the shoulder, comparing its effectiveness to US-PICT of the rotator cuff. METHODS: Patients subjected to US-PICT for extra-shoulder calcific tendinitis (Case Group) were compared to those subjected to US-PICT of the rotator cuff (Control Group). We had pre-procedure Visual Analogue Scale (VAS) pain score, 1- and 3-month VAS of patients of the Case Group, pre-procedure and 3-month VAS of patients of the Control Group. RESULTS: The Case Group consisted of 41 patients (27 women; mean age: 45 ± 9years): 26 gluteus medius, 5 patellar tendon, 3 rectus femoris, 2 gluteus maximus, 2 common extensor tendon, 1 extensor carpi radialis longus, 1 pes anserinus, and 1 peroneus longus. The Control Group included 41 patients (27 women; mean age: 47 ± 11 years). The mean pre-procedure VAS of the Case Group was 8.8 ± 0.7 with a significant (P < .001) drop at 1 month (4.5 ± 0.6) and 3 months (3.6 ± 0.6). The mean pre-procedure VAS of the Control Group was 8 ± 1.4 and dropped to 3.1 ± 1.6 after 3 months (P < .001). Post-treatment VAS at 3 months was not significantly different between two Groups (P = 0.134). Similarly, the decrease of VAS from baseline to 3 months was not significantly different between the two Groups (P = 0.264). CONCLUSIONS: US-PICT is a safe and effective procedure that can be used out of the shoulder. ADVANCES IN KNOWLEDGE: This study demonstrated the safety and effectiveness of US-PICT as a valuable therapeutic option for extra-shoulder calcific tendinitis, with similar clinical outcome to the same procedure performed in the rotator cuff. The technique must be adapted in some deeply located calcifications by means of the use of different needles and by thoroughly planning the access point for the procedure.

Complication of barbotage, acute calcific bursitis treated successfully.

One of the most common causes of chronic shoulder pain that significantly impairs patients' quality of life is rotator cuff calcific tendinitis. The supportive approach of analgesics, anti-inflammatory medications, and physiotherapy is preferred to treat mild symptoms. However, severe intractable symptoms necessitate alternative treatment, and ultrasonography-guided percutaneous barbotage is regarded as an effective treatment technique due to its minimal invasiveness, low cost, and rapid significant pain relief. Post-barbotage complications are reported as acute calcific bursitis along with infection, bleeding, and tendon rupture. In our case, a 41-year-old female presented with a substantial amount of pain shortly after barbotage, which was diagnosed as acute calcific bursitis, a complication of the procedure. Subacromial-subdeltoid steroid injection was used successfully to treat this condition.

Intramuscular migration of calcium deposits into the deltoid muscle: two cases of a rare complication of rotator cuff calcific tendinopathy.

Rotator cuff calcific tendinopathy is a common non-traumatic shoulder pain condition that occurs predominantly in the supraspinatus tendon. Ultrasound-guided percutaneous irrigation of calcific tendinopathy (US-PICT) is a valid treatment in the resorptive phase. A complication of calcific tendinopathy is migration of calcium deposits outside the tendon. The most common site of migration is the subacromialsubdeltoid bursa (SASD). Another, but not frequent, type of migration is the intramuscular migration which mostly affects the supraspinatus, the infraspinatus and the biceps brachii muscles. This paper reports two cases of migration of calcification from the supraspinatus tendon to the deltoid muscle. The aforementioned site of migration has so far never been described in literature. Both patients presented calcification in the resorptive phase and therefore were treated by US-PICT.

Calcific tendinopathy: an unexpected side effect of tyrosine kinase inhibitor?

Musculoskeletal (MSK) pains have been reported during TKI treatment or after its discontinuation in patients with chronic myeloid leukemia (CML). We hypothesized that MSK pains originate from calcific tendinopathy according to preliminary clinical observations. We conducted a retrospective study including CML patients divided into three groups: patients with MSK pain during TKI treatment; asymptomatic patients during TKI treatment; patients with MSK pain after TKI discontinuation. Patients with MSK pain were clinically evaluated, and the presence of calcific deposits was assessed in X-rays of both shoulders and pelvis. Forty-five patients were included; 14 described MSK pain during TKI treatment and 12 after TKI discontinuation. A diagnosis of rotator cuff tendinopathy was retained for 57.7% of patients and of gluteus tendinopathy in 19.2%. The prevalence of calcifications in shoulders and/or hips was 64.3% in symptomatic patients receiving TKIs, 63.2% in asymptomatic patients and 75.0% in patients with MSK pain after TKI treatment.

Calcific tendinopathy of the pronator quadratus muscle: A rare site and cause of ulnar sided wrist pain.

Ulnar -sided wrist pain is a common complaint and can present a diagnostic challenge for a musculoskeletal clinician. Calcific tendinopathy is a well-recognised disorder related to the deposition of calcium hydroxyapatite crystals within tendons. Classically, tendons around the shoulder and the hip joints are the most commonly affected sites. We report a rare site of calcific tendinopathy of the Pronator Quadratus muscle presenting with ulnar-sided wrist pain in a 36-year-old male posing a diagnostic dilemma. This case-report highlights the importance of a thorough clinical evaluation and crucial role of cross-sectional imaging in reaching a diagnosis of calcific tendinopathy of the Pronator Quadratus muscle as unusual cause of ulnar-sided wrist pain. This is the first reported case of calcific tendinopathy in pronator quadratus in the literature we could review.

Efficacy of Ultrasound-Guided Percutaneous Lavage and Biocompatible Electrical Neurostimulation, in Calcific Rotator Cuff Tendinopathy and Shoulder Pain, A Prospective Pilot Study.

Calcific tendinopathy of the shoulder (CTS) is the most common cause of shoulder pain. Conservative treatment is considered as the first therapeutic choice for CTS. The main objective of this study was to assess the effect of US-guided needling (UGN) compared to UGN plus Biocompatible Electrical Neurostimulation (BEN) in the treatment of the CTS. Pilot, prospective, non-interventional, monocentric, and observational study of patients treated for calcific rotator cuff tendinopathy and shoulder pain. Patients' selection, enrollment and interventions were conducted at the Chiparo Physical Medicine and Rehabilitation outpatient facility. Forty adult patients (aged 40−60 years) with a diagnosis of CTS in the acute and colliquative phase were recruited and enrolled into the study. Participants were assessed for self-perceived pain through the Numerical Rating Scale (NRS), and for functional limitation through the Shoulder Pain and Disability Index score (SPADI) at baseline (T0), after 15 days (T1), and after 40 days (T2). As a possible confounding factor between the two treatments' response, the dimension of the tendon calcification was also assessed by US-examination. Through the study, both groups improved their perceived functional performance of the arm (p-value < 0.001). AT T1, the SPADI score decreased by half in both groups, and the improvement remained stable at T2. A multiplicative effect (Time × Treatment) was demonstrated (p-value < 0.001). An improvement in the NRS score was measured at T1, and it remained stable at T2, a multiplicative effect was also reported (p-value < 0.001). The main results of this pilot study provide evidence that UGN plus BEN increases functional performance and reduces shoulder pain in individuals with CTS. Moreover, the tendon calcification dimension at the baseline and the percentage of drainage of the lesion were associated with a functional performance recovery and pain reduction detected after intervention.

Ultrasound-guided percutaneous irrigation of rotator cuff calcific tendinosis. What radiologist should know.

Rotator cuff calcific tendinopathy is a common condition caused by the presence of calcification into the rotator cuff or in the subacromial-subdeltoid bursa. The pathogenetic mechanism of this pathology is still debated. Calcific tendinitis frequently affects the rotator cuff and may cause shoulder pain and reduction of range of motion. It can be diagnosed with conventional radiography, ultrasound, or magnetic resonance imaging. The first therapeutic option includes conservative management based on rest, physical therapy, and oral non-steroid anti-inflammatory administration. Extracorporeal shock wave therapy is a noninvasive technique that can be useful for the fragmentation of calcific deposits. Imaging-guided percutaneous irrigation is currently considered the gold standard technique for the treatment of calcific tendinitis due to its minimal invasiveness and its success rate of about 80%.

Clinical evaluation and management of calcific tendinopathy: an evidence-based review.

Calcific tendinopathy (CT) is an important musculoskeletal condition most commonly seen in the shoulder girdle, accounting for 10-42% of all shoulder pain. Despite the high prevalence within the shoulder region, CT has been demonstrated in many tendons throughout the axial and appendicular skeleton. Unlike degenerative tendinopathies, CT appears to be a self-limiting condition that affects otherwise-healthy tendon with deposition of calcium hydroxyapatite crystals between healthy tenocytes. In patients with functionally limiting symptoms or pain, the clinical course may be accelerated through a multitude of treatments including physical therapy and pain management, extracorporeal shock wave therapy, ultrasound-guided percutaneous lavage (UGPL), and operative debridement. Currently, the most efficacious and frequently utilized treatment for shoulder CT is UGPL due to its ability to effectively reduce calcium burden and pain while limiting soft-tissue damage. However, more evidence regarding the treatment and course of CT is needed before determining the most appropriate treatment at all potential sites of CT.

Predicting long-term outcomes of ultrasound-guided percutaneous irrigation of calcific tendinopathy with the use of machine learning.

OBJECTIVE: To evaluate the performance of two machine learning models in predicting the long-term complete pain resolution in patients undergoing ultrasound-guided percutaneous irrigation of calcific tendinopathy (US-PICT). MATERIALS AND METHODS: Within a 3-year period, 100 consecutive patients who underwent US-PICT for rotator cuff disease were prospectively enrolled. The location, maximum diameter, and type of each calcification were recorded. The degree of calcium retrieval was graded as complete or incomplete. Shoulder pain was assessed with the visual analogue scale (VAS) at baseline, 1-week, 1-month, and 1-year post-treatment. Measurements related to procedural details, patient, and calcification characteristics were used to construct a machine learning model for the prediction of pain at 1-year post-US-PICT. Two distinct models were built, one including VAS data at 1 week and another additionally including pain data at 1-month post-treatment. Variable importance analysis was performed for the 1-week model. Model performance was evaluated by using receiver operating characteristics (ROC) curves and the respective areas under the curve (AUC). RESULTS: The model exhibited an AUC of 69.2% for the prediction of complete pain resolution at 1 year. The addition of VAS scores at 1 month did not significantly alter the performance of the algorithm. Age and baseline VAS scores were the most important variables for classification performance. CONCLUSION: The presented machine learning model exhibited an AUC of almost 70% in predicting complete pain resolution at 1 year. Pain data at 1 month do not appear to improve the performance of the algorithm.

Does intraoperative ultrasound help the surgeon in arthroscopic excision of rotator cuff tendon calcifications ?

PURPOSE: Arthroscopic excision of rotator cuff tendon calcifications is a common procedure in cases where medical treatment has failed. The objective of this study was to evaluate how intraoperative ultrasound contributes to improving the interventional procedure. Our hypothesis was that through the use of ultrasonography the frequency of postoperative residual calcium deposits could be reduced without increasing operating time. METHODS: In a non-randomized single-operator comparative study, 56 patients who underwent arthroscopic excision of calcification were retrospectively included: group 1 (n = 20) without ultrasound guidance and group 2 (n = 36) with guidance. Operating time was measured and localization failures noted. Radiological follow-up was carried out with x-ray images at conventional angles and ultrasound at 1.5, 3 and 6 months postoperatively. Clinical follow-up was based on the Constant score (CS) at 6 months. RESULTS: The mean operating time was 18 min in group 1 (9-33 ± 8.1) and 22 min in group 2 (10-48 ± 7.7) (p = 0.03). The rate of failure to identify calcifications was 8% and 2% in groups 1 and 2, respectively (p = 0.22). At 6 months, four calcifications were still visible on radiography in group 1 vs 1 in group 2 (20% vs 2.7%, p = 0.03). The mean CS increased from 35 to 81 points in group 1 (p < 0.001) and from 34 to 82 points in group 2 (p < 0.001). CONCLUSION: Despite an increase in operating time, intraoperative ultrasound improves the process of excising rotator cuff intratendinous calcifications, prevents localization failures and enables a more complete extraction.

Miositis del subescapular. Una evolución infrecuente en la tendinopatía calcificada. Estudio de un caso / Subscapularis myositis: An uncommon complication in calcific tendinopathy. A case study

RESUMEN La tendinopatía calcificada del hombro se caracteriza por el depósito de cristales de hidroxiapatita en uno o varios tendones del hombro. Dentro de los procesos que ocurren en esta entidad está la fase de reabsorción, en la que los depósitos podrían migrar hacia estructuras adyacentes. Una muy rara complicación es la migración hacia la unión miotendinosa del tendón correspondiente, la cual provoca una importante reacción inflamatoria muscular que puede objetivarse en pruebas complementarias específicas. Presentamos un caso clínico de una tendinopatía calcificante del subescapular, con pos terior migración hacia la unión miotendinosa causando una miositis del mismo.

ABSTRACT Calcific tendinopathy of the shoulder is characterised by the deposit of hydroxy apatite crys tals in one or more tendons of the shoulder. Within the processes that occur within this disorder, there is the resorption phase, in which the deposits could migrate towards adjacent structures. A very rare complication is the migration towards the myotendinous junction of the corresponding tendon, which causes a significant muscular inflammatory reaction that can be seen in specific complementary tests. A clinical case is presented of a subscapular calcific tendinopathy, with subsequent migra tion to the myotendinous junction, causing myositis of the same.

Extensive Ossification of the Achilles Tendon with and without Acute Fracture: A Scoping Review.

Extensive Ossification of the Achilles Tendon (EOAT) is an uncommon condition characterized by the presence of heterotopic ossification within the substance of the Achilles Tendon and is distinct from other tendinopathies associated with tendon mineralization. The purpose of this scoping review of the literature on EOAT is to describe the pathogenesis, patient population, presentation, management, and outcomes of this rare condition. Fifty-four articles were included in the scoping review after screening and selection. According to the literature, EOAT often presents with pain and swelling around the Achilles Tendon and is frequently associated with acute trauma. EOAT is more common in men, and although the exact mechanisms of the pathology are not fully understood, EOAT may demonstrate specific molecular signaling patterns. The lack of knowledge regarding the molecular mechanism may be a significant hindrance to the management of the condition. Even though a standard treatment regimen for EOAT does not exist, conservative management for six months in patients without complications is recommended. Those who have an acute fracture of the ossification should be managed more aggressively and will often require surgical repair with autograft, although there is no standardized procedure at this time. Clinicians should be aware of the typical presentation, risk factors, and management options of patients with EOAT. Additionally, they should be cautious when selecting treatment strategies and conduct a thorough evaluation of long-term outcomes with various treatment modalities, which this review provides. Most important, this review highlights the need for further research to determine the best course of clinical treatment of EOAT injuries, in order to establish a standard treatment regimen.

New bone-like tissue formation in calcific tendinopathy: A case report.

Currently, the pathogenesis of nontraumatic heterotopic ossification (HO), e.g., bone-like tissue in calcific tendinopathy remains unclear. Here, we report a 75-year-old, right-handed Japanese woman who had been on hemodialysis for 3 years and was admitted to our hospital to evaluate pain and swelling of the right forearm. She worked as a cook, and her main job over the 3 most recent years had been the frequent and continuous shredding of cabbage. A radiograph showed the highly radiopaque material on the dorsal aspect of the right wrist and in the right shoulder. The biopsy of this radiopaque material revealed HO with marrow, as well as calcified material. Histomorphometric analysis of the HO identified a severe type of osteitis fibrosa with a fibrous tissue volume to total volume of 19.8% (>0.5% required for diagnosis) and an osteoid volume to bone volume of 20.0% (>15% required for diagnosis). We found more woven bone-like tissue than lamellar bone-like tissue. However, the intact parathyroid hormone level was 3-times the normal upper limit with 203 pg/mL, but histomorphometric analysis of the right iliac crest revealed normal bone structure. These findings indicate that the frequent and continuous shredding action with the right hand contributed to the nontraumatic HO localized on the dorsal aspect of the right wrist.

Sonographic evaluation of the association between calcific tendinopathy and rotator cuff tear: a case-controlled comparison.

OBJECTIVES: To compare the incidence of rotator cuff (RC) tears on shoulder ultrasounds of patients with RC calcific tendinopathy (CaT) to that of a control group without CaT. METHOD: In this retrospective case-control study, 50 shoulder ultrasounds of patients with CaT were compared independently by 2 musculoskeletal radiologists to 50 patients from a control group without CaT to catalog the number and type of RC tears. RC tears in the CaT group were further characterized based on location, into tears in the specific tendon(s) containing calcium versus all tendon tears. RESULTS: RC tears were diagnosed in 38% (19/50) of the control group (16 full-thickness) as compared to 22% (11/50) with CaT (6 full-thickness). The fewer full-thickness tears in the CaT group (12%, 6 of 50) compared to that in the control group (32%, 16 of 50) was statistically significant (P = 0.016, odds ratio 0.29). Only 7 of the 11 tears in the CaT group were in a calcium-containing tendon (3 full-thickness). The fewer calcium-containing tendon tears compared to tears in the control group was also statistically significant (P = 0.006, odds ratio 0.27). Furthermore, the fewer full-thickness calcium-containing tendon tears (6%, 3/50) compared to full-thickness tears in the control group (32%, 16/50) were yet more statistically significant (P = 0.001, odds ratio 0.14). CONCLUSIONS: In patients with shoulder pain and CaT, we observed a decreased number of RC tears and especially calcium-containing tendon tears, as compared to similar demographic patients with shoulder pain but without CaT. Key Points • Patients with rotator cuff calcific tendinopathy have few rotator cuff tears, especially full-thickness tears, compared to a control group without calcific tendinopathy. • The tendons containing the calcium hydroxyapatite deposition were the least likely to have a rotator cuff tear. • Future studies could evaluate if calcium hydroxyapatite deposition provides a protective mechanism against rotator cuff tears. • Musculoskeletal ultrasound is more sensitive than MRI in the evaluation of rotator cuff calcific tendinopathy.

US-guided percutaneous irrigation of calcific tendinopathy of the rotator cuff in patients with or without previous external shockwave therapy.

OBJECTIVES: To compare the outcome of US-guided percutaneous irrigation of calcific tendinopathy (US-PICT) of the rotator cuff in patients with or without previous external shockwave therapy (ESWT). METHODS: We analyzed all patients treated with US-PICT from March 1, 2016, to October 1, 2019, with shoulder pain refractory to conservative management for rotator cuff calcific tendinopathy, diagnosed with ultrasound. Each patient was examined using the Constant-Murley Score (CMS) questionnaire (score 0-100) before and after treatment. We tested CMS differences using the Mann-Whitney U (Wilcoxon rank-sum) test in the two groups. US-PICT was performed placing two or multiple 14G needles, according to the calcification size, inserted under US guidance to create a circuit of irrigation in the calcified tendon. NaCl solution at 38 °C was then injected from the entry needle in a variable amount to hydrate and fragment the calcification, finally allowing for its expulsion through the exit needle. All patients also received an intrabursal steroid injection. RESULTS: From 2016 to 2019, 72 US-PICT treatments were performed on 70 patients (females = 46; males = 26) with a mean age of 49.7 years (SD = 8.7. Thirty-three (47%) underwent previous ESWT, while thirty-seven (53%) had no previous treatments. No treatment-related complications were observed. Follow-up was averagely 14.4 months (median = 11.6, SD = 11.9, range 1-45); 37 patients had a follow-up shorter than 12 months (1-11.6); 35 patients were visited after more than 1 year (12.2-45.6, Table W). Before treatment, the mean CMS was 35 (SD = 21); after treatment, it reached 75.4, with an average CMS improvement of 40.3 points (SD = 23.7, p < 0.001). The comparison of improvement between the ESWT and non-ESWT group yielded no significant difference (p = 0.3). CONCLUSIONS: US-PICT of the rotator cuff is an effective procedure to reduce shoulder pain and increase mobility in patients with calcific tendinopathy, both in short- and long-term time intervals. Previous unsuccessful ESWT does not affect the outcome of US-PICT.

Imaging of calcific tendinopathy around the shoulder: usual and unusual presentations and common pitfalls.

Rotator cuff calcific tendinopathy (RCCT) is a very common condition, characterized by calcium deposition over fibrocartilaginous metaplasia of tenocytes, mainly occurring in the supraspinatus tendon. RCCT has a typical imaging presentation: in most cases, calcific deposits appear as a dense opacity around the humeral head on conventional radiography, as hyperechoic foci with or without acoustic shadow at ultrasound and as a signal void at magnetic resonance imaging. However, radiologists have to keep in mind the possible unusual presentations of RCCT and the key imaging features to correctly differentiate RCCT from other RC conditions, such as calcific enthesopathy or RC tears. Other presentations of RCCT to be considered are intrabursal, intraosseous, and intramuscular migration of calcific deposits that may mimic infectious processes or malignancies. While intrabursal and intraosseous migration are quite common, intramuscular migration is an unusual evolution of RCCT. It is important also to know atypical regions affected by calcific tendinopathy as biceps brachii, pectoralis major, and deltoid tendons. Unusual presentations of RCCT may lead to diagnostic challenge and mistakes. The aim of this review is to illustrate the usual and unusual imaging findings of RCCT that radiologists should know to reach the correct diagnosis and to exclude other entities with the purpose of preventing further unnecessary imaging examinations or interventional procedures.

Identification of Differentially Expressed Genes Associated with Extracellular Matrix Degradation and Inflammatory Regulation in Calcific Tendinopathy Using RNA Sequencing.

Calcific tendinopathy (CT), developed due to calcium hydroxyapatite deposition in the rotator cuff tendon, mostly affects women in their 40 s and 50 s and causes severe shoulder pain. However, the molecular basis of its pathogenesis and appropriate treatment methods are largely unknown. In this study, we identified 202 differentially expressed genes (DEGs) between calcific and adjacent normal tendon tissues of rotator cuff using RNA sequencing-based transcriptome analysis. The DEGs were highly enriched in extracellular matrix (ECM) degradation and inflammation-related processes. Further, matrix metalloproteinase 9 (MMP9) and matrix metalloproteinase 13 (MMP13), two of the enzymes associated with ECM degradation, were found to be highly upregulated 25.85- and 19.40-fold, respectively, in the calcific tendon tissues compared to the adjacent normal tendon tissues. Histopathological analyses indicated collagen degradation and macrophage infiltration at the sites of calcific deposit in the rotator cuff tendon. Our study acts as a foundation that may help in better understanding of the pathogenesis associated with CT, and thus in better management of the disease.

Post-surgical Achilles calcific tendinopathy treated with ultrasound-guided percutaneous irrigation.

Calcific tendinopathy typically affects the shoulder rotator cuff tendons. Its management includes shock wave therapy and US-guided percutaneous irrigation, with surgery being less and less used. Extra-shoulder calcific tendinopathy is relatively infrequent and typically affects the hip. While the diagnostic techniques and the treatment options for shoulder calcific tendinopathy have been extensively described, there are only anecdotic reports on the other sites. In this paper, we have reported an unusual case of non-insertional Achilles calcific tendinopathy which occurred many years after Achilles surgical repair. This condition, which presented similar appearance to that of the rotator cuff calcific tendinopathy, is totally different from the well-known and more common insertional calcific Achilles tendinopathy in terms of pathophysiological, imaging, and clinical findings. Further, we have shown that US-guided percutaneous irrigation might be a safe, technically feasible, mini-invasive, and effective treatment also for Achilles calcific tendinopathy.