Tendinopathy in diabetes mellitus patients—Epidemiology,pathogenesis, and management

Chronic tendinopathy is a frequent and disabling musculo‐skeletal problem affecting the athletic and general populations. The affected tendon is presented with local tenderness, swelling, and pain which restrict the activity of the individual. Tendon degeneration reduces the mechanical strength and predisposes it to rupture. The pathogenic mechanisms of chronic tendinopathy are not fully understood and several major non‐mutually exclusive hypotheses including activation of the hypoxia‐apoptosis‐pro‐inflammatory cytokines cascade, neurovascular ingrowth, increased production of neuromediators, and erroneous stem cell differentiation have been proposed. Many intrinsic and extrinsic risk/causative factors can predispose to the development of tendinopathy. Among them, diabetes mellitus is an important risk/causative factor. This review aims to appraise the current literature on the epidemiology and pathology of tendinopathy in diabetic patients. Systematic reviews were done to summarize the literature on (a) the association between diabetes mellitus and tendinopathy/tendon tears, (b) the pathological changes in tendon under diabetic or hyperglycemic conditions, and (c) the effects of diabetes mellitus or hyperglycemia on the outcomes of tendon healing. The potential mechanisms of diabetes mellitus in causing and exacerbating tendinopathy with reference to the major non‐mutually exclusive hypotheses of the pathogenic mechanisms of chronic tendinopathy as reported in the literature are also discussed. Potential strategies for the management of tendinopathy in diabetic patients are presented.     

Imaging the infrapatellar tendon in the elite athlete

Extensor mechanism injuries constitute a major cause of anterior knee pain in the elite athlete. Sonography and magnetic resonance imaging (MRI) are the imaging methods of choice when assessing the infrapatellar tendon. A comprehensive imaging review of infrapatellar tendon normal anatomy, tendinopathy, and partial/full-thickness tendon tears is provided. The value of imaging the infrapatellar tendon in clinical practice, including whether sonography can predict symptoms in asymptomatic athletes, is discussed. Acute avulsion fractures, including periosteal sleeve avulsion, and chronic avulsion injuries, including Sinding-Larsen-Johansson and Osgood-Schlatter syndromes, are shown. Mimics of infrapatellar tendon pathology, including infrapatellar plica injury, patellar tendon-lateral femoral condyle friction syndrome, and Hoffa's syndrome, are illustrated.     

MR imaging of the tendons of the foot and ankle

Hindfoot pain from tendon pathology is common and seen in a wide range of patients from young athletes to older sedentary individuals. Magnetic resonance (MR) is an excellent technique for imaging tendons and for identifying injuries that can be treated with surgery. MR also demonstrates the presence of bone marrow edema, which is a cause of pain and often a marker for adjacent tendon injury. Finally, MR can reveal other etiologies that cause similar hindfoot pain, such as osteochondral injuries and impingement. In this article, we review the normal MR appearance of the ankle tendons and tendon sheath fluid. MR protocols for imaging the various ankle tendon groups are presented. We discuss the MR appearance of tendon pathology, including tendonosis/ tendinopathy, tenosynovitis and peritendonosis, partial and complete tears, subluxation and dislocation, and entrapment. The Achilles, medial, lateral, and anterior tendon groups are discussed separately so as to focus on the MR appearance specific to each region of the ankle.     

Subpectoral biceps tenodesis

The long head of the biceps brachii (LHB) tendon has long been recognized as a source of shoulder pain. Surgeons have debated the merits of tenotomy versus tenodesis, open versus arthroscopic approaches, and various fixation methods. This article reviews the clinical findings associated with LHB pathology, describes the operative technique of subpectoral biceps tenodesis, and reviews the current literature related to treatment of the symptomatic LHB tendon. The miniopen subpectoral approach is technically less demanding than purely arthroscopic techniques, and offers the potential for improved pain relief without cosmetic deformity by removing most of the LHB and its associated tenosynovium. As the literature on the topic continues to grow, subpectoral biceps tenodesis has emerged as an effective treatment for pathology of the LHB.     

Achilles tendinopathy after treatment with fluoroquinolone

Fluoroquinolone antibiotic therapy is a recognized but poorly understood cause for Achilles tendinopathy. We report here a patient who developed bilateral partial Achilles tendon tears as a result of fluoroquinolone therapy. Ultrasound and MRI were both useful in identifying and distinguishing between Achilles tendinosis and tendon rupture. The current published literature on this problem was also reviewed.     

Imaging of plantar fascia and Achilles injuries undertaken at the London 2012 Olympics

Plantar fascia and distal Achilles injuries are common in elite athletes. Acute athletic injuries of the plantar fascia include acute plantar fasciopathy and partial or complete tears. Underlying most acute injuries is a background of underlying chronic plantar fasciopathy. Injuries may affect the central or less commonly lateral portions of the fascia and acute tears are generally proximal. Athletic Achilles injuries may occur at the mid tendon or the distal insertion, and there may be an underlying chronic tendinopathy. Acute or chronic paratendinopathy may occur as a separate entity or combined with Achilles injury. In this article, the spectrum of athletic injuries of the plantar fascia and Achilles is described, illustrated by imaging findings from the London 2012 Olympic games.     

Chondral print on humeral head: an indirect sign of long head biceps tendon instability

Long head biceps (LHB) tendon pathologies are becoming increasingly recognized causes of shoulder pain in the published literature. Instability of LHB presenting as dislocation or subluxation has been recently recognized as a possible cause of disabling pain or discomfort of the shoulder. A clinical diagnosis of LHB instability is very difficult and often confounding because of association with other shoulder pathologies. However, an early diagnosis of LHB instability is important in order to prevent the evolution of lesions of the biceps pulley until an internal anterosuperior impingement of the shoulder (ASI) and subscapular tear occur. The advent of arthroscopy contributed to enhance understandings. The goal of this article is to describe an arthroscopic sign, the chondral print on the humeral head, associated with a LHB instability, that when present can be very useful to help the surgeon to make the diagnosis of unstable LHB tendon.     

Animal models for the study of tendinopathy

Tendinopathy is a common and significant clinical problem characterised by activity-related pain, focal tendon tenderness and intratendinous imaging changes. Recent histopathological studies have indicated the underlying pathology to be one of tendinosis (degeneration) as opposed to tendinitis (inflammation). Relatively little is known about tendinosis and its pathogenesis. Contributing to this is an absence of validated animal models of the pathology. Animal models of tendinosis represent potential efficient and effective means of furthering our understanding of human tendinopathy and its underlying pathology. By selecting an appropriate species and introducing known risk factors for tendinopathy in humans, it is possible to develop tendon changes in animal models that are consistent with the human condition. This paper overviews the role of animal models in tendinopathy research by discussing the benefits and development of animal models of tendinosis, highlighting potential outcome measures that may be used in animal tendon research, and reviewing current animal models of tendinosis. It is hoped that with further development of animal models of tendinosis, new strategies for the prevention and treatment of tendinopathy in humans will be generated.     

Sonographic evaluation of gluteus medius and minimus tendinopathy

Our objective was to describe the sonographic appearance of the gluteus medius and minimus tendons in normal subjects, and to illustrate the spectrum of sonographic findings in gluteus tendinopathies. Sonography was performed in 20 asymptomatic volunteers. Seventy-five consecutive patients (59 women, 16 men; mean age 57.1 years) presented with pain and point tenderness over the greater trochanter. There were 43 right hips and 32 left hips. Ten patients provided a history of a traumatic incident with subsequent symptoms (mean duration 3.2 months). All patients underwent sonography to assess the site and severity of injury, and to discriminate tendinosis from partial and complete tear. Calcific foci, bony change, and fluid in the trochanteric bursae were noted. Twenty-two patients subsequently underwent surgery. Fifty-three (53 of 75) patients showed sonographic evidence of gluteus medius tendinopathy. Twenty-eight patients were thought to have tendinopathy without discrete tear. Sixteen patients had partial tears and 9 full-thickness tears. Gluteus minimus tendinopathy was detected in 10 of 75 patients. Foci of tendinopathy and partial tears were more common in the deep and anterior portions of the gluteus medius tendon attachment. Eight patients had fluid pooling in the trochanteric bursae. Findings were confirmed in 22 patients at surgery. Sonography can identify gluteus medius and minimus tendinopathy and provides information about the severity of the disease. Electronic Publication     

Evaluation of common elbow pathologies: a focus on physical examination

Elbow tendinopathy accounts for the majority of elbow pathology in patients presenting to upper extremity and sports medicine surgeons. With increased participation in overhead sports in an aging population, the incidence of elbow injuries has risen. A comprehensive knowledge of elbow anatomy and biomechanical function of the elbow complex is prerequisite in the assessment of patients with elbow injuries; however, a thorough understanding of alternative and confounding pathologies is essential for accurate diagnosis. Because tendinopathy, tendonitis, and tendon tears have an anatomic basis for their pathology, a targeted history and meticulous physical examination often yields an accurate clinical diagnosis. The importance of physical examination and provocative examination maneuvers must be stressed in a technologically advanced era where clinical diagnosis is too commonly attained solely by advanced imaging modalities. A revived dedication to the physical examination may enhance our ability to correctly diagnose various pathologies about the elbow. Early and accurate clinical diagnosis is the first step in the proper initiation of treatment modalities and improvement in overall patient outcome.     

Noninsertional Achilles tendinopathy: Pathology and management

Many patients present to their physician's office with the chief complaint of pain at the Achilles tendon. This review discusses the pathology, diagnosis, and treatment of Achilles tendinopathy. Achilles tendinopathy is generally caused by chronic stress to the tendon, leading to a defective arrangement of collagen fibers in the Achilles tendon. This then results in pain and limited function. Ultrasound imaging can help identify the abnormal portion of the tendon. Various treatments are available for Achilles tendinopathy, the most current of which are discussed in this article. Appropriate treatment can potentially lead to a full recovery.     

Diagnosis of tears in rotator-cuff-injuries

Pathology of the rotator cuff is the cause of most common problems at the shoulder joint. Acute injuries are not as frequent as chronic cuff disease, but often they aggravate inflammatory or degenerative tendon alterations, even if they are of minor severity. Traumatic rotator cuff tears predominantly affect the supraspinatus tendon or the rotator interval. The subscapularis tendon is involved in anterior dislocations of the glenohumeral joint or in direct trauma. Plain film radiography still remains the base of all further imaging studies. If only full-thickness tears must be ruled out, double-contrast arthrography and ultrasound are acceptable imaging modalities. However, the former has a drawback in being invasive and does not detect partial tears at the bursal site of the cuff or rotator cuff tendinopathy, whereas the latter heavily depends on the experience of the radiologist and is restricted to the rotator cuff. Nowadays the most comprehensive imaging method is magnetic resonance (MR) imaging. MR imaging enables the detection or exclusion of complete rotator cuff tears with a reasonable accuracy and is also suitable to diagnose further pathologies of the shoulder joint. MR arthrography is valuable in the detection of subtle anatomic details and further improves the differentiation of rotator cuff diseases. Although in comparison MR imaging is still the most expensive imaging method, its high negative predictive value for the diagnosis of complete rotator cuff tears and its reliability evaluating different shoulder joint pathologies make it the preferred imaging modality.     

“Tenomalacia”: a new sonographic sign of tendinopathy?

The purpose of this study was to assess tendon compressibility with sonography in extensor tendinopathy and in asymptomatic extensor tendons of the elbow. Sonography of both elbows was performed in eight patients with a clinical diagnosis of unilateral lateral epicondylitis. Tendons were assessed for compressibility by measuring their thickness before and after compression with the transducer. The same manoeuvre was performed while tendon vascularity was assessed with colour Doppler. All eight cases showed increased compressibility of the common extensor tendon on the painful side compared to the asymptomatic side, as well as increased vascularity with compressible vessels on colour Doppler. Other signs of tendinopathy were hypoechogenicity (n = 8), loss of fibrillar pattern (n = 8), intratendinous calcifications (n = 1), partial tears (n = 3), and enthesophytes (n = 5). Increased tendon compressibility indicative of tendon softening or “tenomalacia” is a new sonographic sign of common extensor tendinopathy. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Value of CT bursography in the evaluation of rotator cuff tears

PURPOSE: To describe the technique and assess the value of subacromial CT bursography in patients with partial surface tear of the rotator cuff tendon. MATERIALS AND METHODS: 15 patients with shoulder pain suggestive of tendinopathy or tear of the rotator cuff were evaluated with subacromial CT bursography. RESULTS: Subacromial CT bursography was normal in 4 patients. Partial surface tear was detected in 7 patients [irregularities (n=2), defect (n=2), superficial tear (n=3)]. Full thickness tear was detected in 4 patients. CONCLUSION: The authors described the technique for subacromial CT bursography to visualize partial surface tears of the rotator cuff tendon. This simple and reliable technique could be an alternative to MR imaging, especially when MR evaluation is not possible.     

Detection and measurement of rotator cuff tears with sonography: analysis of diagnostic errors

OBJECTIVE: The purpose of this study was to analyze the causes of errors in the detection and measurement of rotator cuff tears in our patient population. SUBJECTS AND METHODS: Seventy-one consecutive patients with shoulder pain who were prospectively studied with sonography had subsequent arthroscopy that showed a full-thickness or partial-thickness tear or intact cuff. For sonography and arthroscopy, the length or degree of retraction and width of a tear, when present, was recorded. When there were discrepant findings, representative images were jointly evaluated by the radiologist and orthopedic surgeon to determine the cause of the error. RESULTS: Fifteen detection errors were found, including five misses (three < 5-mm subscapularis and two small partial-thickness tears), four errors inherent with the test (distinguishing large bursal side or extensive partial-thickness from full-thickness tears and tendinopathy from partial-thickness tears), three errors of an unknown cause, two due to misinterpretation, and one error inherent with the patient. Seventeen measurement errors occurred with full-thickness tears, 15 of those in patients with large or massive tears. Bursal thickening (n = 4), non-visualization of the torn tendon end (n = 2), nonretracted tear (n = 2), and complex tear (n = 1) contributed to the errors. Eight measurement errors occurred with partial-thickness tears. Difficulty distinguishing tendinopathy from partial-thickness tears (n = 3) and complex tears (n = 3) accounted for six errors. CONCLUSION: Although infrequent, detection errors were due to limitations inherent with the test or misses. Limitations inherent with the patient and misinterpretation of the findings were rare. Most measurement errors occurred in patients with large or massive cuff tears.     

Stress-shielding as a cause of insertional tendinopathy: the operative technique of limited adductor tenotomy supports this theory

The aetiology of tendinopathy is poorly understood. A new hypothesis proposed argues that tendinopathy may not be purely a tensile injury, rather that altered mechanics such as compression or stress-shielding may be important. Both tendon compression and a decrease in tendon load (stress-shielding) will induce change in a tendon similar to that seen in an insertional tendinopathy. Stress-shielding as a cause of tendinopathy is supported by the clinical success of operative release of adductor longus. This surgery releases the superficial section of the normal adductor longus tendon at a point distal to the insertion. This may have the effect of transferring stress from the superficial section of the tendon to the stress-shielded deeper portion, and the induction of normal loads in both the deeper and superficial portions of the tendon may assist in tendon recovery. This interesting hypothesis and clinical intervention require further investigation     

Progression of long head of the biceps brachii tendon abnormality on magnetic resonance imaging after rotator cuff repair

ObjectivesTo correlate the deterioration of preserved long head of biceps tendon (LHB) after rotator cuff repair with preoperative and postoperative MRI factors.MethodsTotal of 209 shoulder joints (F:M = 145:64; mean age 57.4 years) which underwent rotator cuff repair and at least two postoperative MRI scans over 10 months after surgery were included. LHB integrity was graded with a five point severity scale. LHB deterioration was defined by increased composite score of integrity and extent score between the preoperative and second postoperative MRI. For preoperative and postoperative MRI factors, size and location of superior cuff -supraspinatus and infraspinatus- and subscapularis tears, fatty degeneration of rotator cuff, preoperative LHB status, subluxation of LHB, superior labral tear, acromion type, repaired rotator cuff status, postoperative capsulitis and acromioplasty state were assessed. Logistic regression was used to evaluate the association between LHB deterioration and aforementioned factors. Same analysis was conducted for 62 shoulder joints with a long-term follow-up MRI.ResultsOf the 209 shoulders, 49.3% (n = 103) showed LHB deterioration on short-term follow-up MRI. In long-term follow-up subgroup, 32 LHBs were further deteriorated. In multivariate analysis, fatty degeneration of superior cuff showed significant association with LHB deterioration in both short-term (p = .04, p = .007) and long-term subgroups (p = .004, p = .005) among preoperative and postoperative factors, respectively.ConclusionsDegree of fatty degeneration in superior cuff is associated with LHB deterioration on postoperative MRI.Advances in knowledgeOur results support that tenotomy or tenodesis of LHB should be considered during rotator cuff repair, especially in patients with advanced fatty degeneration of rotator cuff.     

Moderate value of non-contrast magnetic resonance imaging after non-dislocating shoulder trauma

Purpose

The purpose of the present study was to determine the value of shoulder magnetic resonance imaging (MRI) obtained in the community setting interpreted by musculoskeletal radiologists in patients with shoulder pain initiated by a single non-dislocating shoulder trauma.

Methods

In 56 of 61 consecutive patients who underwent shoulder arthroscopy due to pain after a single non-dislocating shoulder trauma, the data sets of non-contrast MRI were complete. These were retrospectively interpreted by three radiologists specialized on musculoskeletal MRI who were blinded for patients’ history and who did not have access to the reports of arthroscopy. Standard evaluation forms were used to assess the MRIs for superior labrum anterior and posterior (SLAP) lesions, anterior or posterior labrum lesions, lesions of the long head of biceps tendon (LHB) and for partial tears of the supraspinatus tendon and the upper quarter of the subscapularis tendon. Quality of the MRI was assessed by each radiologist on a four-point scale.

Results

The pooled sensitivity for the three radiologists for the detection of SLAP lesions was 45.0 %, for anterior or posterior labrum tears 77.8 and 66.7 %, for lesions of the LHB 63.2 % and for partial tears of the supraspinatus or subscapularis tendon tears 84.8 and 33.3 %. Corresponding inter-rater reliabilities were poor (SLAP lesions) to substantial (anterior labrum tears). Quality of MRI only influenced the accuracy for the detection of posterior labrum tears.

Conclusion

A non-contrast shoulder MRI obtained in the community setting after non-dislocating shoulder trauma has a moderate sensitivity for most intraarticular pathologies when interpreted by musculoskeletal radiologists. Accuracy is dependent on the observer and not on the assessed quality.

Level of evidence

Case series, Level IV.