Physiopathology of intratendinous calcific deposition

Management of Achilles and patellar tendinopathy: what we know, what we can do

Tendinopathies are challenging conditions frequent in athletes and in middle-aged overweight patients with no history of increased physical activity. The term “tendinopathy” refers to a clinical condition characterised by pain, swelling, and functional limitations of tendons and nearby structures, the effect of chronic failure of healing response. Tendinopathies give rise to significant morbidity, and, at present, only limited scientifically proven management modalities exist. Achilles and patellar tendons are among the most vulnerable tendons, and among the most frequent lower extremity overuse injuries. Achilles and patellar tendinopathies can be managed primarily conservatively, obtaining good results and clinical outcomes, but, when this approach fails, surgery should be considered. Several surgical procedures have been described for both conditions, and, if performed well, they lead to a relatively high rate of success with few complications. The purpose of this narrative review is to critically examine the recent available scientific literature to provide evidence-based opinions on these two common and troublesome conditions.

Alterations of bone material properties in adult patients with X-linked hypophosphatemia (XLH)

X-linked hypophosphatemia (XLH) caused by PHEX mutations results in elevated serum FGF23 levels, renal phosphate wasting and low 1,25-dihydroxyvitamin D. The glycophosphoprotein osteopontin, a potent inhibitor of mineralization normally degraded by PHEX, accumulates within the bone matrix. Conventional therapy consisting of supplementation with phosphate and vitamin D analogs is burdensome and the effects on bone material poorly characterized. We analyzed transiliac bone biopsies from four adult patients, two of them severely affected due to no diagnosis and no treatment until adulthood. We used light microscopy, qBEI and FTIRI to study histology, histomorphometry, bone mineralization density distribution, properties of the organic matrix and size of hypomineralized periosteocytic lesions. Non-treatment resulted in severe osteomalacia, twice the amount of mineralized trabecular volume, multiple osteon-like perforations, continuity of lamellae from mineralized to unmineralized areas and distinctive patches of woven bone. Periosteocytic lesions were larger than in treated patients. The latter had nearly normal osteoid thicknesses, although surface was still elevated. The median calcium content of the matrix was always within normal range, although the percentage of lowly mineralized bone areas was highly increased in non-treated patients, resulting in a marked heterogeneity in mineralization. Divalent collagen cross-links were evident independently of the mineral content of the matrix. Broad osteoid seams lacked measurable pyridinoline, a mature trivalent cross-link and exhibited considerable acidic lipid content, typically found in matrix vesicles. Based on our results, we propose a model that possibly integrates the relationship between the observed mineralization disturbances, FGF23 secretion and the known osteopontin accumulation in XLH.

Differentiation of retropharyngeal calcific tendinitis and retropharyngeal abscess: a case series and review of the literature

Introduction

Retropharyngeal calcific tendinitis (RCT) is a self-limiting aseptic inflammation of the tendon of the longus colli muscle, which can be clinically and radiologically misdiagnosed as abscess formation. This is a particular challenge for ENT specialists. However, articles about RCT are highly underrepresented in ENT journals and existing articles in ENT journals almost exclusively report overtreatment.

Methods

This study presents five patients, in which the diagnosis of RCT was delayed and of which one patient underwent incision and draining of a suspected retropharyngeal abscess under general anesthesia. In addition, the literature on the reported cases of RCT, between 1990 and 2020 was reviewed. For each case, epidemiological characteristics, complaints on presentation, symptoms, imaging and laboratory finding and treatment were summarized and compared to our own findings.

Results

In all the five patients, the correct diagnosis was delayed. One patient underwent incision and draining of a suspected RA under general anesthesia. All patients received antibiotic treatment. The literature review revealed a total of 116 reported cases of RCT. A total of 99 CT scans and 72 MRI showed soft tissue swelling in 89.6% and calcifications in 91.4% of the cases, 6.9% received invasive treatment.

Conclusion

This article emphasizes the importance of knowledge about RCT and its management to avoid invasive and potentially harmful treatment. The focus in establishing the correct diagnosis of RCT is the identification and correct interpretation of clinical symptoms together with the specific radiological findings.

Electronic supplementary material

The online version of this article (10.1007/s00405-020-06057-w) contains supplementary material, which is available to authorized users.

Role of Biomaterials and Controlled Architecture on Tendon/Ligament Repair and Regeneration

Engineering synthetic scaffolds to repair and regenerate ruptured native tendon and ligament (T/L) tissues is a significant engineering challenge due to the need to satisfy both the unique biological and biomechanical properties of these tissues. Long-term clinical outcomes of synthetic scaffolds relying solely on high uniaxial tensile strength are poor with high rates of implant rupture and synovitis. Ideal biomaterials for T/L repair and regeneration need to possess the appropriate biological and biomechanical properties necessary for the successful repair and regeneration of ruptured tendon and ligament tissues.

Extracorporeal shock wave therapy mechanisms in musculoskeletal regenerative medicine

Extracorporeal shockwave therapy (ESWT) is a popular non-invasive therapeutic modality in the medical field for the treatment of numerous musculoskeletal disorders. This technique first emerged around the 1980s as extracorporeal shockwave lithotripsy and has been studied since then for its application towards orthopedics and traumatology. ESWT works by the emission of acoustic waves (shockwaves) that carry energy and can propagate through tissues. Shockwaves can generate interstitial and extracellular responses, producing many beneficial effects such as: pain relief, vascularization, protein biosynthesis, cell proliferation, neuro and chondroprotection, and destruction of calcium deposits in musculoskeletal structures. The combination of these effects can lead to tissue regeneration and significant alleviation of pain, improving functional outcomes in injured tissue. Considering these facts, ESWT shows great potential as a useful regenerative medicine technique for the treatment of numerous musculoskeletal injuries.

Common Musculoskeletal Disorders in the Elderly: The Star Triad

Musculoskeletal disorders are debilitating conditions that significantly impair the state of health, especially in elderly subjects. A pathological triad of inter-related disorders that are highly prevalent in the elderly consists of the following main “components”: sarcopenia, tendinopathies, and arthritis. The aim of this review is to critically appraise the literature relative to the different disorders of this triad, in order to highlight the pathophysiological common denominator and propose strategies for personalized clinical management of patients presenting with this combination of musculoskeletal disorders. Their pathophysiological common denominator is represented by progressive loss of (focal or generalized) neuromuscular performance with a risk of adverse outcomes such as pain, mobility disorders, increased risk of falls and fractures, and impaired ability or disability to perform activities of daily living. The precise management of these disorders requires not only the use of available tools and recently proposed operational definitions, but also the development of new tools and approaches for prediction, diagnosis, monitoring, and prognosis of the three disorders and their combination.

Crowned dens syndrome: a neurologist's perspective

Crowned dens syndrome is an under-recognized entity that can mimic neurological disease, in particular meningitis or giant-cell arteritis. We present a 48-year-old woman presenting with an inflammatory meningitis-like syndrome with headache and neck stiffness. Lumbar puncture was normal and computed tomography (CT) of the atlantoaxial joint showed abnormal calcifications around the odontoid process, leading to a tentative diagnosis of crowned dens syndrome. In addition, signs of active inflammation in and around the dens were present on cervical MR imaging. Since CDS can mimic meningitis or giant-cell arteritis, neurologists should be aware of this entity. If CDS is suspected, the bone window on the head CT scan can lead to the diagnosis. On the other hand, asymptomatic periodontoid calcifications are common and should not preclude further investigations.

Pathological Mineralization: The Potential of Mineralomics

Pathological mineralization has been reported countless times in the literature and is a well-known phenomenon in the medical field for its connections to a wide range of diseases, including cancer, cardiovascular, and neurodegenerative diseases. The minerals involved in calcification, however, have not been directly studied as extensively as the organic components of each of the pathologies. These have been studied in isolation and, for most of them, physicochemical properties are hitherto not fully known. In a parallel development, materials science methods such as electron microscopy, spectroscopy, thermal analysis, and others have been used in biology mainly for the study of hard tissues and biomaterials and have only recently been incorporated in the study of other biological systems. This review connects a range of soft tissue diseases, including breast cancer, age-related macular degeneration, aortic valve stenosis, kidney stone diseases, and Fahr’s syndrome, all of which have been associated with mineralization processes. Furthermore, it describes how physicochemical material characterization methods have been used to provide new information on such pathologies. Here, we focus on diseases that are associated with calcium-composed minerals to discuss how understanding the properties of these minerals can provide new insights on their origins, considering that different conditions and biological features are required for each type of mineral to be formed. We show that mineralomics, or the study of the properties and roles of minerals, can provide information which will help to improve prevention methods against pathological mineral build-up, which in the cases of most of the diseases mentioned in this review, will ultimately lead to new prevention or treatment methods for the diseases. Importantly, this review aims to highlight that chemical composition alone cannot fully support conclusions drawn on the nature of these minerals.

Heterotopic ossification: radiological and pathological review

Background Heterotopic Ossification (HO) is a common condition referring to ectopic bone formation in soft tissues. It has two major etiologies, acquired (more common) and genetic. The acquired form is closely related to tissue trauma. The exact pathogenesis of this disease remains unclear; however, there is ongoing research in prophylactic and therapeutic treatments that is promising. Conclusions Due to HO potential to cause disability, it is so important to differentiate it from other causes in order to establish the best possible management.

Subcutaneously engineered autologous extracellular matrix scaffolds with aligned microchannels for enhanced tendon regeneration: Aligned microchannel scaffolds for tendon repair

Improved strategies for the treatment of tendon defects are required to successfully restore mechanical function and strength to the damaged tissue. This remains a scientific and clinical challenge, given the tendon's limited innate regenerative capacity. Here, we present an engineering solution that stimulates the host cell's remodeling abilities. We combined precision-designed templates with subcutaneous implantation to generate decellularized autologous extracellular matrix (aECM) scaffolds that had highly aligned microchannels after removal of templates and cellular components. The aECM scaffolds promoted rapid cell infiltration, favorable macrophage responses, collagen-rich extracellular matrix (ECM) synthesis, and physiological tissue remodeling in rat Achilles tendon defects. At three months post-surgery, the mechanical strength of tenocyte-populated 'neo-tendons' was comparable to pre-injury state tendons. Overall, we demonstrated an in vivo bioengineering strategy for improved restoration of tendon tissue, which also offers wider implications for the regeneration of other highly organized tissues.

Calcium hydroxyapatite deposition disease: Imaging features and presentations mimicking other pathologies

OBJECTIVE

Calcium hydroxyapatite depositional disease (HADD) is usually asymptomatic and self-limiting; however, when there is an associated inflammatory process or HADD occurs in an unusual location, it may mimic trauma, infection, or neoplasm. The purpose of this article is to review the imaging features of HADD and how to distinguish it from more worrisome entities that can have similar appearances.

CONCLUSION

An understanding of the presentations of HADD is important to allow early and confident diagnosis. In particular, familiarity with presentations that resemble more ominous pathologies is essential to avoid costly and time-consuming workup or intervention.

Pharmacological Inhibition of Rac1 Activity Prevents Pathological Calcification and Enhances Tendon Regeneration

Tendinopathy is a common disease, which is characterized by pain, swelling, and dysfunction. At the late stage of tendinopathy, pathological changes may occur, such as tendon calcification. Previously, we have shown that in situ tendon stem/progenitor cells (TSPCs) underwent osteogenesis in the inflammatory niche in diseased tendons. In this study, we demonstrate that this process is accompanied by the activation of Ras-related C3 botulinum toxin substrate 1 (Rac1) signaling. A specific inhibitor NSC23766 significantly downregulated catabolic factors and calcification-related genes and rescued the tenogenesis gene expression of TSPCs under the influence of Interleukin (IL)-1β in vitro. For in vivo evaluation, we further developed a drug delivery system to encapsulate Rac1 inhibitor NSC23766. Chitosan/β-glycerophosphate hydrogel encapsulated NSC23766 effectively impeded tendon calcification and enhanced tendon regeneration in rat Achilles tendinosis. Our findings indicated that inhibiting Rac1 signaling could act as an effective intervention for tendon pathological calcification and promote tendon regeneration, thus providing a new therapeutic strategy.

Lateral versus central tendon-splitting approach to insertional Achilles tendinopathy: a retrospective study

INTRODUCTION

This study aimed to compare operative outcomes between the lateral approach (LA) and the central approach (CA) to insertional Achilles tendinopathy (IAT).

METHODS

We retrospectively reviewed patients who underwent surgical treatment for IAT using the LA or CA. Patients' demographic data, postoperative complications and satisfaction rate were reviewed. Clinical outcomes were prospectively assessed preoperatively, at three months postoperatively and at the last visit, including patients' visual analogue scale (VAS) scores for pain, American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale scores and 36-item Short Form Health Survey (SF-36) scores.

RESULTS

There were 39 patients in the LA group and 32 in the CA group. In each group, average VAS and AOFAS Scale scores improved significantly. SF-36 scores improved in most parameters. No significant difference in baseline score; average AOFAS Scale score at each visit; and mean VAS score preoperatively and at last visit; satisfaction rate; and overall complication rate were observed between the groups. The mean VAS score in the LA group at postoperative three months was significantly lower than that in the CA group (2.7 ± 2.5 vs. 4.4 ± 3.0; p = 0.016). There were significantly more cases of delayed wound healing in the LA group than in the CA group (2.6% vs. 15.6%; p = 0.049).

CONCLUSION

Both approaches had comparable outcomes for IAT in terms of functional improvement, pain relief, overall enhancement of patients' health condition and overall postoperative complication rate. The LA provided better short-term pain relief and reduced delayed wound healing compared with the CA.

Treatment of a calcific bursitis of the medial collateral ligament: a rare cause of painful knee

Medial knee pain is common in clinical practice and can be caused by various conditions. In rare cases, it can even be by calcific bursitis of the medial collateral ligament (MCL). Treatment of calcific bursitis and/or calcification of the MCL classically includes observation, local injections, shockwave therapy and surgical resection. We report a case of nontraumatic medial knee pain poorly responsive to conservative treatments. Ultrasound (US) imaging revealed a massive lobed hyperechoic formation with partial acoustic shadow in the MCL context compatible with calcific bursitis, and magnetic resonance imaging (MRI) confirmed the presence of the bursa's calcific deposit surrounded by hyperintense signal compatible with pericalcific edema. We performed a double-needle ultrasound-guided percutaneous lavage (UGPL), which is today a fairly common treatment for many musculoskeletal disorders, such as rotator cuff calcific tendinopathy and elbow extensor tendons pathology, but regarding the knee, it is not part of ordinary care. This report shows the clinical and imaging presentation of calcific bursitis of the MCL and describes in detail the technique to perform the UGPL with a system of two needles, two syringes and a double connection to ensure a correct lavage of the calcium deposit without significant intrabursal pressure increase and consequently without pain during the procedure.

Characterization of a Novel Calcific Achilles Tendinopathy Model in Mice: Contralateral Tendinopathy Induced by Unilateral Tenotomy

Achilles tendinopathy is a significant clinical disease characterized by activity-related pain, focal movement limitation, and intratendinous imaging changes. However, treatment of Achilles tendinopathy has been based mainly on theoretical rationale and clinical experience because of its unclear underlying pathogenesis and mechanism. The purpose of the study was to develop a simple but reproducible overuse-induced animal model of Achilles tendinopathy in mice to better understand the underlying mechanism and prevent calcific Achilles tendinopathy. A total of 80 C57/B6 mice (8 or 9 weeks old) were employed and randomly divided into control and experimental groups. Unilateral Achilles tenotomy was performed on the right hind limbs in the experiment group. 12 weeks after unilateral Achilles tenotomy, the onset of Achilles tendinopathy in the contralateral Achilles tendon was determined by radiological assessment, histologic analysis, electron microscopy observation, and biomechanical test. The onset of calcific Achilles tendinopathy in contralateral Achilles tendon was confirmed after 12 weeks of unilateral tenotomy. The contralateral Achilles tendon in the experimental group was characterized as hypercellularity, neovascularization, and fused collagen fiber disarrangement, compared with the control group. Importantly, intra-tendon endochondral ossification and calcaneus deformity were featured in contralateral Achilles tendon. In addition, poor biomechanical properties in the contralateral Achilles tendon revealed the incidence of Achilles tendinopathy. We hereby introduce a novel, simple, but reproducible spontaneous contralateral calcific Achilles tendinopathy model in mice, which represents overuse conditions during tendinopathy development in humans. It should be a useful tool to further study the underlying pathogenesis of calcific Achilles tendinopathy.

Longus Colli Tendinitis: The Lost Twin of Retropharyngeal Abscess

Longus colli calcific tendinitis is a rare condition which mimics the alarming condition, retropharyngeal abscess. Clinically, the patient presents which acute cervical pain, dysphagia and fever. Since this condition is little known to otorhinolaryngologists, it is usually misdiagnosed as a retropharyngeal abscess which is more common. This is a case report of a 52 year old female who presented with complaints of neck pain and difficulty in swallowing along with fever which were acute in onset. Clinically, the symptoms overlapped with those of a retropharyngeal abscess. The diagnosis was confirmed as longus colli calcific tendinitis. Longus colli calcific tendinitis is a rare entity which can be diagnosed solely based on radiological investigation. The knowledge of this disease is crucial to otorhinolaryngolists as it avoids over treatment, unwarranted chance surgical exposure.

Interleukin‑10 promotes proliferation and migration, and inhibits tendon differentiation via the JAK/Stat3 pathway in tendon‑derived stem cells in vitro

Tendon repair follows a slow course of early inflammatory, proliferative and remodeling phases, which commonly results in the failure and loss of normal biomechanical properties. Previous studies have demonstrated that tendon-derived stem cells (TDSCs) are vital healing cells and that mRNA expression of anti-inflammatory cytokine interleukin (IL)-10 is significantly upregulated at the late inflammatory phase. To explore how IL-10 may impact tendon healing, the present study investigated the in vitro effects of IL-10 on TDSCs isolated from rat Achilles tendons. Cellular activities of TDSCs and the expression levels of tendon cell markers were measured treatment with IL-10 and subsequent performance of wound healing assays, reverse transcription-quantitative polymerase chain reaction and western blot analyses. The results demonstrated that IL-10 treatment markedly increased the proliferative capacity of TDSCs. In addition, IL-10 significantly enhanced cell migration when compared with the control cells. Furthermore, IL-10 treatment significantly activated the JAK/Stat3 signaling pathway and inhibited the protein expression of tendon cell markers, including scleraxis and tenomodulin. Notably, IL-10 treatment also reduced the gene expression levels of type 1 collagen, type 3 collagen, lumican and fibromodulin in TDSCs. These findings indicated that IL-10 enhanced cell proliferation and migration, and inhibited tenogenic differentiation in TDSCs in vitro. Reducing the negative effects whilst enhancing the positive effects of IL-10 may be a potential therapeutic target in tendon repair.

Surgical Correction of Haglund's Triad Using a Central Tendon-Splitting Approach: A Retrospective Outcomes Study

We evaluated the surgical outcomes of Haglund's triad using a central tendon-splitting approach, with Achilles tendon partial detachment and debridement, excision of the retrocalcaneal bursa, resection of Haglund's prominence, and reattachment of the Achilles tendon. The medical records of 22 patients (22 heels) who had undergone surgical correction of Haglund's triad from January 2010 to December 2015 were reviewed retrospectively. The visual analog scale pain score, American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot scale score, and 36-item Short-Form Health Survey physical and mental component scores were prospectively collected preoperatively, 6 months postoperatively, and at the last visit. The scores of a subjective question involving satisfaction were prospectively collected at the last visit. Possible risk factors were also evaluated. We reviewed the data from 12 females and 10 males, with the mean age of 59.2 ± 7.3 years and a mean follow-up duration of 15.1 ± 4.6 months. Significant improvement was found in the mean visual analog scale pain score, average American Orthopaedic Foot and Ankle Society Ankle-Hindfoot scale score, and 36-item Short-Form Health Survey physical component scale score. The overall satisfaction rate was 77.3% (17 of 22). Postoperative complications included 2 cases of delayed wound healing and 1 case of sensation loss over the heel wound. No Achilles tendon rupture or wound infection developed. Gender and body mass index did not affect the surgical outcomes. The surgical technique we used for Haglund's triad provided effective pain relief, function improvement, and overall enhancement of patients' health condition. More research is required to further evaluate the outcomes of our surgical approach to treat Haglund's triad and the possible risk factors.

Clinical and Imaging Features of Longus Colli Calcific Tendinitis: An Analysis of Ten Cases

Background

Longus colli calcific tendinitis (LCCT) exhibits characteristic clinical features; thus, misidentification can be avoided once it is learned. There is a lack of reports on this disease. In this study, we analyzed the imaging and clinical features of LCCT in 10 patients.

Methods

We retrospectively reviewed the radiolographic findings, laboratory data and clinical features of 10 patients diagnosed with LCCT between January 2015 and June 2017. All patients were treated with medical treatment consisting of intravenous methylprednisolone 125 mg twice and oral nonsteroidal anti-inflammatory drug administration.

Results

On clinical findings, all 10 patients complained of severe posterior neck pain and cervical motion limitation. Odynophagia was present in nine patients. The mean time from symptom onset to hospital visit was 2.9 days. The mean time to symptom relief was 4.6 days. Of the 10 patients, three patients were admitted through the emergency room. There were five patients in the medical records who were transferred from another hospital. On the laboratory data, the mean value of C-reactive protein and erythrocyte sedimentation rate were 2.08 mg/dL (reference range, < 0.30 mg/dL) and 36.9 mm/hr (reference range, < 20 mm/hr), respectively. Leukocytosis was found in only two patients and fever was not present all patients. On radiographic findings, calcification was present on computed tomography images of all patients. The calcification was located at the lower part of the C1 arch, except for one case where calcification occurred in the anterolateral aspect of the C4–5 disc space. The mean value of the retropharyngeal space was 7.2 mm.

Conclusions

LCCT, a rare disease, has characteristic radiographic findings and clinical features. Understanding such characteristics of this disease can prevent unnecessary testing and misdiagnosis.

Isolation, culture and biological characteristics of multipotent porcine tendon-derived stem cells

Tendon-derived stem cells (TDSCs), a postulated multi-potential stem cell population, play significant role in the postnatal replenishment of tendon injuries. However, the majority of experimental materials were obtained from horse, rat, human and rabbit, but rarely from pig. In this research, 1‑day‑old pig was chosen as experimental sample source to isolate and culture TDSCs in vitro. Specific markers of TDSCs were then characterized by immunofluorescence and reverse transcription polymerase chain reaction (RT‑PCR) assays. The results showed that TDSCs could be expanded for 11 passages in vitro. The expression of specific markers, such as collagen Ⅰ, collagen Ⅲ, α‑smooth muscle actin (α‑SMA), CD105 and CD90 were observed by immunofluorescence and RT‑PCR. TDSCs were induced to differentiate into adipocytes, osteoblasts and chondrocytes, respectively. These results suggest that TDSCs isolated from porcine tendon exhibit the characteristics of multipotent stem cells. TDSCs, therefore, may be potential candidates for cellular transplantation therapy and tissue engineering in tendon injuries.

Acute Calcific Tendonitis of the Longus Colli

BACKGROUND

Acute calcific tendonitis of the longus colli (ACTLC) is an aseptic inflammatory response to deposition of calcium in the longus colli muscle tendons. Although reports in the literature are scarce, ACTLC likely represents an underreported disease process that routinely goes misdiagnosed. We report a case of ACTLC and provide a brief review of the literature.

CASE REPORT

A 45-year-old otherwise healthy female presented with a 3-day history of progressive neck pain, decreased neck mobility, and odynophagia. She exhibited tenderness over the right posterolateral neck with limited neck flexion and rotation. Flexible fiber-optic laryngoscopy revealed moderate posterior pharyngeal wall edema extending from the palatal-pharyngeal sphincter down to the level of the epiglottis. A computed tomography (CT) scan of the neck with contrast revealed an amorphous calcification in the longus colli muscle and a prevertebral fluid collection without rim enhancement. A diagnosis of ACTLC was presumed. The patient was successfully managed with nonsteroidal antiinflammatory drugs, corticosteroids, and antibiotics and reported complete resolution of symptoms on follow-up.

CONCLUSION

The clinical presentation and laboratory findings of ACTLC are nonspecific; however, a CT scan revealing a calcific deposition in the retropharyngeal space confirms the diagnosis. Spontaneous resolution during the course of several weeks warrants conservative treatment with analgesia and antiinflammatory medications. Awareness of ACTLC must be increased to avoid diagnostic errors and prevent unnecessary medical interventions.

Arthroscopic treatment of symptomatic calcific periarthritis on the medial side of the knee after posterior cruciate ligament reconstruction: Case report and literature review

Calcific periarthritis in the distal femur is a rare condition. Forty two year old Asian male visited to the outpatient clinic of orthopedic department with acute excruciating knee pain. The arthroscopic posterior cruciate ligament (PCL) reconstruction was performed 20 years ago with the bonepatellar tendon-bone (BPTB) autograft combined with Trevira (polyethylene terephthalate) artificial ligament. Severe tenderness was noted incidentally over the medial epicondyle area of the distal femur which the cancellous screw was inserted for PCL reconstruction, without any preceding trauma history or medial joint line tenderness due to degenerative change. The poorly defined calcific deposition was found in plain radiograph. The arthroscopic debridement of the calcification and screw removal from the distal femur was performed due to resist to conservative treatment with analgesics. After operation, the symptoms were resolved completely. The arthroscopic debridement of calcific periarthritis should be considered in specific cases, such as refractory cases with conservative management during 4–6 weeks. We present the arthroscopic treatment of the symptomatic calcific periarthritis on distal femur after PCL reconstruction can be effective.

Examination of concomitant glenohumeral pathologies in patients treated arthroscopically for calcific tendinitis of the shoulder and implications for routine diagnostic joint exploration

BACKGROUND

Glenohumeral exploration is routinely performed during arthroscopic removal of rotator cuff calcifications in patients with calcific tendinitis of the shoulder (CTS). However, evidence on the prevalence of intraarticular co-pathologies is lacking and the benefit of glenohumeral exploration remains elusive. The aim of the present study was to assess and quantify intraoperative pathologies during arthroscopic removal of rotator cuff calcifications in order to determine whether standardized diagnostic glenohumeral exploration appears justified in CTS patients.

METHODS

One hundred forty five patients undergoing arthroscopic removal of calcific depots (CD) that failed conservative treatment were included in a retrospective cohort study. Radiographic parameters including number/localization of calcifications and acromial types, intraoperative arthroscopic findings such as configuration of glenohumeral ligaments, articular cartilage injuries, and characteristics of calcifications and sonographic parameters (characteristics/localization of calcification) were recorded.

RESULTS

One hundred forty five patients were analyzed. All CDs were removed by elimination with a blunt hook probe via "squeeze-and-stir-technique" assessed postoperatively via conventional X-rays. Neither subacromial decompression nor refixation of the rotator cuff were performed in any patient. Prevalence of glenohumeral co-pathologies, such as partial tears of the proximal biceps tendon (2.1%), superior labral tears from anterior to posterior (SLAP) lesions (1.4%), and/or partial rotator cuff tears (0.7%) was low. Most frequently, glenohumeral articular cartilage was either entirely intact (ICRS grade 0 (humeral head/glenoid): 46%/48%) or showed very mild degenerative changes (ICRS grade 1: 30%/26%). Two patients (1.3%) required intraarticular surgical treatment due to a SLAP lesion type III (n = 1) and an intraarticular rupture of CD (n = 1).

CONCLUSIONS

Routine diagnostic glenohumeral exploration does not appear beneficial in arthroscopic treatment of CTS due to the low prevalence of intraarticular pathologies which most frequently do not require surgical treatment. Exploration of the glenohumeral joint in arthroscopic removal of CD should only be performed in case of founded suspicion of relevant concomitant intraarticular pathologies.

Acute calcific tendinitis of the longus colli muscle masquerading as a retropharyngeal abscess: A case report and review of the literature

•

The longus colli muscle is situated on the anterior surface of C1-C2 disk space.

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Calcific tendinitis of the longus colli muscle is a reactive self-limiting inflammatory response to the subacute deposition of calcium hydroxyapatite crystals on the tendon of the muscle.

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The clinical presentation is usually mistaken with other serious conditions, such as a retropharyngeal abscess, disk herniation, neck tumor or trauma.

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The importance of recognizing this pathology lies in preventing its misdiagnosis and mismanagement.

•

This condition is usually managed conservatively with nonsteroidal anti-inflammatory drugs (NSAIDs).

Introduction

Acute calcific longus colli tendinitis, also known as retropharyngeal or acute calcific prevertebral tendinitis, is a reactive self-limiting inflammatory response to acute or subacute deposition of amorphous calcium hydroxyapatite crystals in the tendons of the longus colli muscle, anterior to the C1–C2 disk space.

Case presentation

A 53-year-old man presented with a complaint of neck pain and odynophagia over a few days. Blood test findings showed mild leukocytosis and elevated C-reactive protein level. Computed tomography findings showed mild edematous prevertebral thickening involving the retropharyngeal space, predominantly on the left side, with no appreciable surrounding peripheral enhancement. A small amount of linear calcification/ossification involving the superior fibers of the left longus colli muscle, anterior to the C1 arch were also noted.

Discussion

The patient’s presentation could be easily misdiagnosed as a retropharyngeal abscess. However, the presence of subtle findings on CT would lead to the correct diagnosis. The management of this condition is mainly with nonsteroidal anti-inflammatory drugs.

Conclusion

This study presents the characteristic radiological features of retropharyngeal calcific tendinitis. These features are subtle and could be missed. Once an accurate diagnosis is made, treatment with nonsteroidal anti-inflammatory drugs is indicated. The purpose of this case report is to highlight this rare condition’s diagnosis and management.

Efficacy of triamcinolone acetate and methylprednisolone acetonide for intrabursal injection after ultrasound-guided percutaneous treatment in painful shoulder calcific tendonitis: a randomized controlled trial

Background Ultrasound-guided percutaneous irrigation of calcific tendinopathy (US-PICT) with intrabursal steroid injection is an elective treatment for painful rotator cuff calcific tendinopathy. Purpose To compare the efficacy of post-US-PICT intrabursal 40 mg injection of triamcinolone acetonide (TA) versus methylprednisolone acetate (MA). Material and Methods Forty patients (22 women; mean age 48.7 ± 7.2 years) with painful shoulder calcific tendinopathy, treated with TA or MA injected intrabursally after US-PICT, were included in this randomized controlled trial. At baseline and after 1, 7, 15, 30, 45, and 180 days, patients underwent US and clinical examination, using Constant (CS) and VAS (VS) scores. Complications and analgesic use were also recorded. Results Compared to baseline, at the 45-day follow-up, TA and MA group showed a similar improvement (Δ) in CS (42 ± 10 versus 36 ± 9 points) and VS (-4.4 ± 1.3 versus -3.6 ± 1.3 points). At the 180-day follow-up, the improvement was higher in TA versus MA (ΔCS: 53 ± 7 versus 44 ± 7 points; ΔVS: -4.9 ± 1.1 versus -3.9 ± 1 points). Multivariate analysis showed a mean CS higher ( P = 0.02) in TA versus MA group, while VS was similar. TA had a 5 × higher ( P = 0.007) chance of reaching complete remission (CS = 100 points) than MA group. A progressive decrease in analgesic use, concomitant to a significant and similar reduction of bursitis and calcifications, was observed in both groups. No major complications occurred. Conclusion Two-needle US-PICT with intrabursal steroid injection is safe and effective. The chance of reaching better scores and, even more important for a clinical perspective, of functional recovery, is higher in patients treated with TA than MA.

Ultrasound Characteristics of the Achilles Tendon in Tophaceous Gout: A Comparison with Age- and Sex-matched Controls

OBJECTIVE

To investigate the frequency and distribution of characteristics of the Achilles tendon (AT) in people with tophaceous gout using musculoskeletal ultrasound (US).

METHODS

Twenty-four participants with tophaceous gout and 24 age- and sex-matched controls without gout or other arthritis were recruited. All participants underwent a greyscale and power Doppler US examination. The AT was divided into 3 anatomical zones (insertion, pre-insertional, and proximal to the mid-section). The following US characteristics were assessed: tophus, tendon echogenicity, tendon vascularity, tendon morphology, entheseal characteristics, bursal morphology, and calcaneal bone profile.

RESULTS

The majority of the participants with tophaceous gout were middle-aged men (n = 22, 92%) predominately of European ethnicity (n = 14, 58%). Tophus deposition was observed in 73% (n = 35) of tendons in those with gout and in none of the controls (p < 0.01). Intratendinous hyperechoic spots (p < 0.01) and intratendinous power Doppler signal (p < 0.01) were more frequent in participants with gout compared to controls. High prevalence of entheseal calcifications, calcaneal bone cortex irregularities, and calcaneal enthesophytes were observed in both gout participants and controls, without differences between groups. Intratendinous structural damage was rare. Hyperechoic spots were significantly more common at the insertion compared to the zone proximal to the mid-section (p < 0.01), but between-zone differences were not observed for other features.

CONCLUSION

US features of urate deposition, tophus, and vascularization are present throughout the AT in patients with tophaceous gout. Despite crystal deposition, intratendinous structural changes are infrequent. Many characteristics observed in the AT in people with tophaceous gout, particularly at the calcaneal enthesis, are not disease-specific.

Value of ultrasonography in the diagnosis of gout in patients presenting with acute arthritis

OBJECTIVE

To evaluate the value of ultrasonographic features of crystal deposition for diagnosing gout in patients presenting with acute arthritis.

MATERIALS AND METHODS

Ultrasound scanning of the most inflamed joint was performed on 89 consecutively enrolled patients with acute arthritis. Two radiologists independently reviewed the ultrasound images, and a consensus was achieved with a third radiologist when the interpretations of four key ultrasound features of gout differed. Arthrocentesis and crystal analysis using compensated polarized light microscopy of aspirates are considered the gold standards for gout diagnosis.

RESULTS

Fifty-three (60%) patients had gout, whereas the remaining 36 (40%) had non-gout arthritis. The mean serum uric acid level was 7.1 mg/dl in patients with gout and 4.7 mg/dl in patients with non-gout arthritis. Three US features differed significantly (p < 0.001) between patients with gout and non-gout arthritis: the double contour sign (42 vs. 8%, respectively), intra-articular aggregates (58 vs. 8%), and tophi (40 vs. 0%). No statistically significant differences in detecting intra-tendinous aggregates (32 vs. 17%, p = 0.14) were observed. The sensitivity and specificity of the double contour sign were 42 and 92%, respectively; those of the intra-articular aggregates were 58 and 92%; and those of tophi were 40 and 100%. The positive predictive values for these three features ranged from 88 to 100%, whereas the negative predictive values ranged from 52 to 60%.

CONCLUSIONS

When the prevalence is high, these three ultrasound features may be a useful adjunct in the diagnosis of acute gout, particularly when specialized microscopic techniques are not available.

Statin-induced calcific Achilles tendinopathy in rats: comparison of biomechanical and histopathological effects of simvastatin, atorvastatin and rosuvastatin

PURPOSE

Accumulating clinical evidence indicates the risk of tendinopathy and spontaneous and/or simultaneous tendon ruptures associated with statin use. This experimental study was designed to evaluate and compare the biomechanical and histopathological effects of the three most commonly prescribed statins (simvastatin, atorvastatin and rosuvastatin) on the Achilles tendon in rats.

METHODS

Statins were administered by gavage to rats at daily doses of 20 and 40 mg/kg for 3 weeks. One week later, the Achilles tendons were dissected and their biomechanical properties, including ultimate tensile force, yield force and elastic modulus, were determined. The samples were stained with haematoxylin-eosin and examined under a light microscope. The biomechanical properties of the tibia were tested by three-point bending test. Bone mineral density (BMD) and the lengths of tibias were measured by computed tomography.

RESULTS

All the statins caused deterioration of the biomechanical parameters of the Achilles tendon. Histopathological analysis demonstrated foci of dystrophic calcification only in the statin-treated groups. However, the number and the total area of calcific deposits were similar between the statin groups. The biomechanical parameters of tibias were improved in all the statin groups. BMD in the statin-treated groups was not significantly different from the control group.

CONCLUSION

All the statins tested are associated with calcific tendinopathy risk of which full awareness is required during everyday medical practice. However, statin-associated improvement of bone biomechanical properties is a favourable feature which may add to their beneficial effects in atherosclerotic cardiovascular disease, especially in the elderly.

Effect of Bone Marrow Aspirate Concentrate-Platelet-Rich Plasma on Tendon-Derived Stem Cells and Rotator Cuff Tendon Tear

Bone marrow aspirate concentrates (BMACs) and platelet-rich plasma (PRP) are good sources to control the differentiation of tendon-derived stem cells (TDSCs), but there has been no study about the effect of the BMAC-PRP complex on TDSCs and tendinopathy. The aim of this study was to investigate the effect of BMAC-PRP on the TDSCs and to find the therapeutic effect of BMAC-PRP on the rotator cuff tendon tear. The chondrogenic and osteogenic potential of TDSCs decreased, but the adipogenic potential of TDSCs revealed no significant difference when they were cocultured with BMAC-PRP. Cell proliferation was significantly greater in TDSCs cocultured with BMAC-PRP than in TDSCs. The degree of wound closure (percentage) was different between TDSCs and TDSCs with BMAC-PRP. There was no significant difference in expression of collagen type I and type III in immunocytochemical staining in the presence of BMAC-PRP. Initial visual analog scale (VAS) score was 5.8 ± 1.9, which changed to 5.0 ± 2.3 at 3 weeks and 2.8 ± 2.3 at 3 months after the BMAC-PRP injection (p < 0.01). The American Shoulder Elbow Surgeon score changed from 39.4 ± 13.0 at baseline to 52.9 ± 22.9 at 3 weeks and 71.8 ± 19.7 at 3 months after the injection (p < 0.01). The initial torn area of the rotator cuff tendon was 30.2 ± 24.5 mm2, and this area was reduced to 22.5 ± 18.9 mm2 at 3 months, but the change was not significant (p > 0.05). The data indicate that BMAC-PRP enhances the proliferation and migration of TDSCs and prevents the aberrant chondrogenic and osteogenic differentiation of TDSCs, which might provide a mechanistic basis for the therapeutic benefits of BMAC-PRP for rotator cuff tendon tear.

A high-glucose diet affects Achilles tendon healing in rats

Chronic and acute tendinopathies are difficult to treat and tendon healing is generally a very slow and incomplete process and our general understanding of tendon biology and regeneration lags behind that of muscle or bone. Although still largely unexplored, several studies suggest a positive effect of nutritional interventions on tendon health and repair. With this study, we aim to reveal effects of a high-glucose diet on tendon neoformation in a non-diabetic rat model of Achilles tenotomy. After surgery animals received either a high-glucose diet or a control diet for 2 and 4 weeks, respectively. Compared to the control group, tendon repair tissue thickness and stiffness were increased in the high-glucose group after 2 weeks and gait pattern was altered after 1 and 2 weeks. Cell proliferation was up to 3-fold higher and the expression of the chondrogenic marker genes Sox9, Col2a1, Acan and Comp was significantly increased 2 and 4 weeks post-surgery. Further, a moderate increase in cartilage-like areas within the repair tissue was evident after 4 weeks of a high-glucose diet regimen. In summary, we propose that a high-glucose diet significantly affects tendon healing after injury in non-diabetic rats, potentially driving chondrogenic degeneration.

Plantar fascia enthesopathy is highly prevalent in diabetic patients without peripheral neuropathy and correlates with retinopathy and impaired kidney function

BACKGROUND

Aim of this study was to evaluate the prevalence of plantar fascia (PF) enthesopathy in Type 2 diabetes mellitus (T2DM) patients without distal peripheral neuropathy (DPN).

METHODS

We recruited 50 T2DM patients without DPN and 50 healthy controls. DPN was excluded using the Michigan Neuropathy Screening Instrument (MNSI). All patients underwent a bilateral sonographicevaluation of the enthesealportion of the PF.

RESULTS

PF thickness was significantly higher in T2DM patients (p<0.0001). T2DM patients presented a higher prevalence of entheseal thickening (p = 0.002), enthesophyte (p = 0.02) and cortical irregularity (p = 0.02). The overall sum of abnormalities was higher in T2DM patients (p<0.0001), as was the percentage of bilateral involvement (p = 0.005). In a logistic regression analysis, retinopathy predicted entheseal thickening (OR 3.5, p = 0.05) and enthesophytes (OR 5.13, p = 0.001); reduced eGFR predicted enthesophytes (OR 2.93, p = 0.04); body mass index (BMI) predicted cortical irregularity (OR 0.87, p = 0.05); mean glucose predicted enthesophyte (OR 1.01, p = 0.03); LDL cholesterol predicted cortical irregularity (OR 0.98, p = 0.02).

CONCLUSIONS

Our data suggest that T2DM is associated with PF enthesopathyindependently of DPN.

Ultrasound-Guided Percutaneous Treatment for Calcific Tendinitis of the Rotator Cuff

Calcific tendinitis is a common pathology of the rotator cuff. More prevalent in women of middle age, calcific tendinitis is often extremely painful and can cause a significant decrease in patient quality of life. The following case study demonstrates the important role of sonography in diagnosis and treatment of calcific tendinitis.

The tenocyte phenotype of human primary tendon cells in vitro is reduced by glucocorticoids

Background

The use of corticosteroids (e.g., dexamethasone) as treatment for tendinopathy has recently been questioned as higher risks for ruptures have been observed clinically. In vitro studies have reported that dexamethasone exposed tendon cells, tenocytes, show reduced cell viability and collagen production. Little is known about the effect of dexamethasone on the characteristics of tenocytes. Furthermore, there are uncertainties about the existence of apoptosis and if the reduction of collagen affects all collagen subtypes.

Methods

We evaluated these aspects by exposing primary tendon cells to dexamethasone (Dex) in concentrations ranging from 1 to 1000 nM. Gene expression of the specific tenocyte markers scleraxis (Scx) and tenomodulin (Tnmd) and markers for other mesenchymal lineages, such as bone (Alpl, Ocn), cartilage (Acan, Sox9) and fat (Cebpα, Pparg) was measured via qPCR. Cell viability and proliferation was calculated using a MTS Assay. Cell death was measured by LDH assay and cleaved caspase-3 using Western Blot. Gene expression of collagen subtypes Col1, Col3 and Col14 was analyzed using qPCR.

Results

Stimulation with Dex decreased cell viability and LDH levels. Dex also induced a significant reduction of Scx gene expression and a marked loss of fibroblast like cell shape. The mRNA for all examined collagen subtypes was found to be down-regulated. Among non-tendinous genes only Pparg was significantly increased, whereas Acan, Alpl and Sox9 were reduced.

Conclusions

These results indicate a Dex induced phenotype drift of the tenocytes by reducing scleraxis expression. Reduction of several collagen subtypes, but not cell death, seems to be a feature of Dex induced tissue degeneration.

Return to Sports After Arthroscopic Treatment of Rotator Cuff Calcifications in Athletes

BACKGROUND

Arthroscopic treatment of calcific deposits of rotator cuff tears has been described with successful results in the general population. However, despite the high frequency of this condition, there is no information in the literature regarding arthroscopic treatment of rotator cuff calcifications in athletes.

PURPOSE

To analyze the time to return to sport, clinical outcomes, and complications of complete arthroscopic removal of intratendinous calcific deposits and repair of the tendon lesion without acromioplasty in athletes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This study retrospectively evaluated 24 consecutive patients with a mean age of 36.2 years. The mean follow-up was 59 months (range, 24-108 months). Patients completed a questionnaire focused on the time to return to sport and treatment course. Pre- and postoperative functional assessment was performed using the Constant score and University of California Los Angeles (UCLA) score. Pain was assessed by visual analog scale (VAS). Radiographs and magnetic resonance imaging (MRI) were performed to evaluate the recurrence of calcifications and the indemnity of the supraspinatus tendon repair.

RESULTS

Of the 24 patients, 23 (95.8%) were able to return to sports; 91.3% returned to the same level. The mean time to return to play was 5.3 months (range, 3-9 months): 26% of patients (6/23) returned to sports in less than 4 months, 61% (14/24) returned between 4 and 6 months, and 13% (3/24) returned after the sixth month. The mean Constant score increased from 26.9 preoperatively to 89.7 postoperatively (P < .001), and the UCLA score increased from 17.3 preoperatively to 33.2 postoperatively (P < .001). Significant improvement was obtained for pain (mean VAS, 8.4 [before surgery] vs 0.6 [after]; P < .001). The overall majority (91.6%) of patients were satisfied with their result. MRI examination at last follow-up (79% of patients) showed no tendon tears.

CONCLUSION

In athletes with calcifying tendinitis of the supraspinatus tendon with failed nonoperative treatment, complete arthroscopic removal of calcific deposits and tendon repair without acromioplasty results in significant pain relief and improvement in functional outcomes. Most patients return to the same level of proficiency regardless of the type of sport and the level of competition before injury, with 91.6% of patients satisfied with their results.

Sex and gender disparity in pathology, disability, referral pattern, and wait time for surgery in workers with shoulder injury

BACKGROUND

The role of sex as an important biological determinant of vulnerability to sustaining injury and gender as a social determinate of access to resources, referral for medical care and perceived disability remains conflicted in injured workers. The purpose of this study was to examine sex and gender disparity following a compensable work-related shoulder injury.

METHODS

This study involved cross-sectional analyses of data of two independent samples of workers with shoulder injury. Measures of disability and pain were the Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and Numerical Pain Rating Scale (NPRS) for patients seen at an Early Shoulder Physician Assessment (ESPA) program and the American Shoulder and Elbow Surgeons (ASES) assessment form and Visual Analogue Scale (VAS) for the sample who underwent surgery.

RESULTS

The files of 1000 (443 females, 557 men) consecutive patients seen at an ESPA program and 150 (44 females, and 106 men) consecutive patients who underwent rotator cuff surgery (repair or decompression) were reviewed. Significant gender disparity was observed in the referral pattern of injured workers seen at the ESPA program who were referred for surgical consultation (22 vs. 78 % for females and males respectively, p < 0.0001). The independent rotator cuff surgical group had a similar gender discrepancy (29 % vs. 71 %, p < 0.0001). The timeframe from injury to surgery was longer in women in the surgical group (p = 0.01). As well, women waited longer from the date of consent to date of surgery (p = 0.04). Women had higher incidence of repetitive injuries (p = 0.01) with men reporting higher incidence of falls (p = 0.01). Women seen at the ESPA program were more disabled than men (p = 0.02). Women in both samples had a higher rate of medication consumption than men (p = 0.01 to <0.0001). Men seen at the ESPA program had a higher prevalence of full thickness rotator cuff tears (p < 0.0001) and labral pathology (p = 0.01). However, these pathologies did not explain gender disparity in the subsample of ESPA who were referred for surgical consultation or those who had surgery.

CONCLUSIONS

Sex and gender disparity exists in workers with shoulder injuries and is evident in the mechanism of injury, perceived disability, medication consumption, referral pattern, and wait time for surgery.

Assessment of enthesitis in patients with psoriatic arthritis using clinical examination and ultrasound

BACKGROUND

Enthesitis is a major feature of psoriatic arthritis. However, clinical assessment of enthesitis is known to lack accuracy and have poor interobserver reliability.

OBJECTIVE

To determine effect of training on clinical assessment of enthesitis and to compare ultrasonography with clinical examination for the detection of entheseal abnormalities.

METHODS

20 rheumatologists performed repeated assessment of enthesitis in patients with established psoriatic arthritis before and after a 2-hour training session in standardised enthesitis count according to Leeds Enthesitis Index (LEI) and Spondyloarthritis Research Consortium of Canada Enthesitis Index (SPARCC). Moreover, 20 patients underwent clinical and ultrasonographic examination of entheses to evaluate consensus-based elementary lesions of enthesitis.

RESULTS

Training significantly increased Intra-class Correlation Coefficient for LEI from 0.18 to 0.82 and for SPARCC from 0.38 to 0.67. Ultrasound examination showed high associations between hypoechogenicity and increased thickness of the entheses and clinical examination. There was no correlation between erosions and enthesophytes found by ultrasound and clinical assessments.

CONCLUSION

Training in standardised enthesitis scoring systems significantly improved clinical assessments of enthesitis and should be performed before use in daily clinical practice. Ultrasound revealed more advanced stages of enthesitis, such as enthesophytes and erosions, which were not detected with clinical examination.

Case report - calcification of the medial collateral ligament of the knee with simultaneous calcifying tendinitis of the rotator cuff

BACKGROUND

Calcification of the medial collateral ligament (MCL) of the knee is a very rare disease. We report on a case of a patient with a calcifying lesion within the MCL and simultaneous calcifying tendinitis of the rotator cuff in both shoulders.

CASE PRESENTATION

Calcification of the MCL was diagnosed both via x-ray and magnetic resonance imaging (MRI) and was successfully treated surgically. Calcifying tendinitis of the rotator cuff was successfully treated applying conservative methods.

CONCLUSION

This is the first case report of a patient suffering from both a calcifying lesion within the medial collateral ligament and calcifying tendinitis of the rotator cuff in both shoulders. Clinical symptoms, radio-morphological characteristics and macroscopic features were very similar and therefore it can be postulated that the underlying pathophysiology is the same in both diseases. Our experience suggests that magnetic resonance imaging and x-ray are invaluable tools for the diagnosis of this inflammatory calcifying disease of the ligament, and that surgical repair provides a good outcome if conservative treatment fails. It seems that calcification of the MCL is more likely to require surgery than calcifying tendinitis of the rotator cuff. However, the exact reason for this remains unclear to date.

Shoulder Conditions: Diagnosis and Treatment Guideline

The following guideline covers a wide array of shoulder conditions seen in the workers' compensation, as well as the nonworkers' compensation, population. The guideline is intended to help establish work relatedness and aid in making the diagnosis of shoulder injuries and degenerative conditions. It also provides a nonoperative and operative guideline for the treatment of several shoulder conditions, not limited to rotator cuff tears, subacromial impingement syndrome, acromioclavicular arthritis and dislocations, as well as glenohumeral arthritis.

Outcomes after quadriceps tendon repair in patients over 80 years of age

BACKGROUND

Quadriceps tendon (QT) ruptures are uncommon and mostly occur in those who are 50-60 years of age. Timely surgical repair can result in a good functional outcome, however, little is known about the outcome in the older patient.

METHODS

A retrospective review of all QT ruptures between 2009 and 2014 was conducted. Patients over the age of 80 were included. Those with penetrating trauma or partial ruptures were excluded. A chart review was undertaken to gather demographic and operative details. The patients were contacted by phone or by mail to have Lysholm and Rougraff scores completed.

RESULTS

Of the 32 QT ruptures identified, 6 (19%) patients were eligible for inclusion in our study. They were predominantly (83%) males with a mean age of 81.38 years. The mean follow up was 54 months. The mean Lysholm score at last follow up was 84.8/100, which falls within the range of a good outcome. The mean Rougraff score was 21.3/25, which is an excellent outcome. All patients felt they were close to their premorbid level of mobility.

CONCLUSION

Good outcomes can be expected with QT repair in older patients, resulting in restoration of the pre-injury level of mobility. Level of evidence: Level V case series.

Treatment of Calcified Insertional Achilles Tendinopathy by the Posterior Midline Approach

The present study investigated the clinical outcomes of the posterior midline approach in the treatment of 34 patients with significantly calcified insertional Achilles tendinopathy. The posterior midline approach was applied for the surgical treatment of 34 patients with chronic significantly calcified insertional Achilles tendinopathy after failed conservative treatment. Gastrocnemius recession was performed simultaneously for patients with gastrocnemius contracture. The Fowler-Philip angle and parallel pitch lines were measured before surgery, and the visual analog scale, Tegner score, and Victorian Institute of Sport tendon study group score were recorded before and after surgery. The mean follow-up period was 45.2 ± 17.7 (range 24 to 84) months. After surgery, the visual analog scale score had decreased notably, and the Tegner score and Victorian Institute of Sport tendon study group score had increased significantly. The posterior midline approach can achieve satisfactory outcomes in the treatment of significantly calcified insertional Achilles tendinopathy, and gastrocnemius recession (Strayer procedure) should be performed for patients with gastrocnemius contracture to improve the surgical outcome.

Tendon mineralization is progressive and associated with deterioration of tendon biomechanical properties, and requires BMP-Smad signaling in the mouse Achilles tendon injury model

Ectopic tendon mineralization can develop following tendon rupture or trauma surgery. The pathogenesis of ectopic tendon mineralization and its clinical impact have not been fully elucidated yet. In this study, we utilized a mouse Achilles tendon injury model to determine whether ectopic tendon mineralization alters the biomechanical properties of the tendon and whether BMP signaling is involved in this condition. A complete transverse incision was made at the midpoint of the right Achilles tendon in 8-week-old CD1 mice and the gap was left open. Ectopic cartilaginous mass formation was found in the injured tendon by 4weeks post-surgery and ectopic mineralization was detected at 8 to 10weeks post-surgery. Ectopic mineralization grew over time and volume of the mineralized materials of 25-weeks samples was about 2.5 fold bigger than that of 10-weeks samples, indicating that injury-induced ectopic tendon mineralization is progressive. In vitro mechanical testing showed that max force, max stress and mid-substance modulus in the 25-weeks samples were significantly lower than the 10-weeks samples. We observed substantial increases in expression of bone morphogenetic protein family genes in injured tendons 1week post-surgery. Immunohistochemical analysis showed that phosphorylation of both Smad1 and Smad3 was highly increased in injured tendons as early as 1week post-injury and remained high in ectopic chondrogenic lesions 4-weeks post-injury. Treatment with the BMP receptor kinase inhibitor (LDN193189) significantly inhibited injury-induced tendon mineralization. These findings indicate that injury-induced ectopic tendon mineralization is progressive, involves BMP signaling and associated with deterioration of tendon biomechanical properties.

Influence of Thyroid Hormones on Tendon Homeostasis

Tendinopathies have a multifactorial etiology driven by extrinsic and intrinsic factors. Recent studies have elucidated the importance of thyroid hormones in the alteration of tendons homeostasis and in the failure of tendon healing after injury. The effects of thyroid hormones are mediated by receptors (TR)-α and -β that seem to be ubiquitous. In particular, T3 and T4 play an antiapoptotic role on tenocytes, causing an increase in vital tenocytes isolated from tendons in vitro and a reduction of apoptotic ones; they are also able to influence extra cellular matrix proteins secretion in vitro from tenocytes, enhancing collagen production. From a clinical point of view, disorders of thyroid function have been investigated only for rotator cuff calcific tendinopathy and tears. In this complex scenario, further research is needed to clarify the role of thyroid hormones on the onset of tendinopathies.

Rehabilitation of Tendon Problems in Patients with Diabetes Mellitus

Exercise is crucial in the management of diabetes mellitus and its associated complications. However, individuals with diabetes have a heightened risk of musculoskeletal problems, including tendon pathologies. Diabetes has a significant impact on the function of tendons due to the accumulation of advanced glycation end-products in the load-bearing collagen. In addition, tendon vascularity and healing may be reduced due to diabetes-induced changes in the peripheral vascular system, and impaired synthesis of collagen and glycosaminoglycan. The current chapter presents an evidence-based discussion of considerations for the rehabilitation of tendon problems in people with diabetes. The following conditions are discussed in detail - calcific tendinopathy, tenosynovitis, tendon rupture, and non-calcifying tendinopathy. Common diabetes-related findings are presented, along with their potential impact on tendinopathy management and suggested modifications to standard tendinopathy treatment protocols. A holistic approach should be used to optimize musculotendinous function, including a comprehensive exercise prescription addressing strength, flexibility, and aerobic fitness.

Role of the ERK1/2 Signaling Pathway in Osteogenesis of Rat Tendon-Derived Stem Cells in Normoxic and Hypoxic Cultures

BACKGROUND

Ectopic ossification and increased vascularization are two common phenomena in the chronic tendinopathic tendon. The increased vascularization usually leads to an elevated local oxygen tension which is one of micro-environments that can influence differentiate status of stem cells.

OBJECTIVE

This study aimed to investigate the osteogenesis capacity of rat tendon-derived stem cells TDSCs (rTDSCs) in normoxic and hypoxic cultures, and to study the role of ERK1/2 signaling pathway in this process.

METHODS

rTDSCs were subjected to osteogenesis inductive culture in hypoxic (3% O2) and normoxic (20% O2) conditions. The inhibitor U0126 was added along with culture medium to determine the role of ERK1/2 signaling pathway. Cell viability, cell proliferation, alizarin red staining, alkaline phosphatase (AKP) activity, gene expression (ALP, osteocalcin, collagen I and RUNX2) and protein expression (p-ERK1/2 and RUNX2) of osteogenic-cultured rTSDCs were analyzed in this study.

RESULTS

Hypoxic and normoxic culture had no effects on cell viability of rTDSCs, whereas the proliferation potential of rTDSCs was significantly increased in hypoxic culture. The osteogenesis capacity of rTDSCs in normoxic culture was significantly promoted compared with hypoxic culture, which was reflected by an increased alizarin red staining intensity, an elevated ALP activity, and the up-regulated gene (ALP, osteocalcin, collagen I and RUNX2) or protein (RUNX2) expression of osteogenic makers. However, the osteogenesis capacity of rTDSCs in both hypoxic and normoxic cultures was attenuated by the inhibitor U0126.

CONCLUSION

Normoxic culture promotes osteogenic differentiation of rTDSCs compared with the hypoxic culture, and the ERK1/2 signaling pathway is involved in this process.

Intramuscular migration of calcium hydroxyapatite crystal deposits involving the rotator cuff tendons of the shoulder: report of 11 patients

OBJECTIVE

The intent of the study is to describe an unusual pattern of intramuscular migration of calcific deposits related to hydroxyapatite deposition disease (HADD) involving the rotator cuff, to illustrate the characteristic imaging features of this phenomenon, and to discuss the clinical significance of such migration.

MATERIALS AND METHODS

A series of cases of intramuscular accumulation of calcium hydroxyapatite crystals collected over a 7-year period at multiple hospitals within the same academic institution were retrospectively reviewed.

RESULTS

The patient group was composed of seven men and four women, ranging in age from 51 to 79 years, with a mean age of 63 years. All subjects presented with acute shoulder pain. The majority of subjects reported the spontaneous onset of the symptoms (64%), while others reported weight lifting (27%) and a fall on the arm (9%) as the mechanisms of injury. The right shoulder was affected in 73% of the subjects. The supraspinatus was the most commonly affected muscle (82%), followed by the infraspinatus muscle (36%).

CONCLUSIONS

Knowledge of the imaging features of intramuscular migration of hydroxyapatite deposits is important in order to avoid the erroneous diagnosis of other causes of muscle edema and inflammation such as myotendinous injury, myositis, subacute denervation, and neoplasm.

Enzymatic Dissolution of Biocomposite Solids Consisting of Phosphopeptides to Form Supramolecular Hydrogels

Enzyme-catalyzed dephosphorylation is essential for biomineralization and bone metabolism. Here we report the exploration of using enzymatic reaction to transform biocomposites of phosphopeptides and calcium (or strontium) ions to supramolecular hydrogels as a mimic of enzymatic dissolution of biominerals. (31) P NMR shows that strong affinity between the phosphopeptides and alkaline metal ions (e.g., Ca(2+) or Sr(2+) ) induces the formation of biocomposites as precipitates. Electron microscopy reveals that the enzymatic reaction regulates the morphological transition from particles to nanofibers. Rheology confirms the formation of a rigid hydrogel. As the first example of enzyme-instructed dissolution of a solid to form supramolecular nanofibers/hydrogels, this work provides an approach to generate soft materials with desired properties, expands the application of supramolecular hydrogelators, and offers insights to control the demineralization of calcified soft tissues.