Spontaneous rupture of the Achilles tendon - a sign of hyperlipoproteinaemia (HLP) type II

An Unusual Case of Xanthoma of Bilateral Achilles Tendon with Gouty Infiltration: A Rare Case Report

Achilles tendon xanthoma is a benign and rare disease with a high incidence in patients having familial hypercholesterolemia. Patients present with or without pain and thickened tendons. Gout is seen in patients with hyperuricemia. Coexistence of xanthoma and gout is extremely rare. We searched the PubMed literature with ‘Xanthoma’ and ‘Gout’ as keywords and could find only one case report. Imaging modalities such as radiography and ultrasonography, play a vital role in diagnosing this condition early, hence helping the patient to commence the use of potentially lifesaving lipid-lowering therapeutic agents. Magnetic resonance imaging is helpful in delineating the morphological changes, exact measurements, and eventually in treatment planning. It helps to rule out early involvement of other tendons by the same pathology. We present a case of a 25-year-old male patient who presented to our institute with bilateral large symmetrical swelling in the posterior aspects of ankles for 4 years, with normal serum and blood parameters. Bilaterality, enormous size and normal blood and serum parameters make this case unique.

The impact of cholesterol deposits on the fibrillar architecture of the Achilles tendon in a rabbit model of hypercholesterolemia

Background

Increased tendon pain and tendon damage is a significant complication related to hyperlipidemia. Unlike the well-established pathogenesis associated with increased serum concentrations of total cholesterol, triglycerides, and low-density lipoprotein in atherosclerotic cardiovascular disease, the role of hyperlipidemia in promoting tendon damage remains controversial and requires mechanistic clarity.

Methods

In this study, we analyzed the consequences of hypercholesterolemia on the integrity of the collagen-based architecture of the Achilles tendon. The Achilles tendons from rabbits fed with normal-cholesterol (nCH) and high-cholesterol (hCH) diets were analyzed. We studied the morphology of tendons, distribution of lipids within their collagen-rich milieu, the relative amounts of fibrillar collagen I and collagen III, and selected biomechanical parameters of the tendons at the macroscale and the nanoscale.

Results

Histological assays of hCH tendons and tenosynovium demonstrated hypercellular areas with increased numbers of macrophages infiltrating the tendon structure as compared to the nCH tendons. While Oil Red staining revealed lipid-rich deposits in the hCH tendons, hybridization of tendon tissue with the collagen hybridizing peptide (CHP) demonstrated damage to the collagen fibers. Fourier-transform infrared (FTIR) spectra showed the presence of distinct peaks consistent with the presence of cholesterol ester. Additionally, the hCH tendons displayed regions of poor collagen content that overlapped with lipid-rich regions. The hCH tendons had a substantial fourfold increase in the collage III to collagen I ratio as compared to the nCH tendons. Tendons from the hCH rabbits showed poor biomechanical characteristics in comparison with control. The biomechanical changes were evident at the macrolevel and the nanolevel of tendon structure.

Conclusions

Our findings support the hypothesis that hypercholesterolemia coincides with the weakening of the tendons. It is likely that the intimate contact between collagen fibrils and cholesterol deposits contributes to the weakening of the fibrillar structure of the tendons.

Ultrasonography of the Achilles Tendon in Hypercholesterolemia

The ultrasonographic (US) appearance of Achilles tendon was examined in 34 patients with hypercholesterolemia (10 with familial (FH), and 24 with secondary hypercholesterolemia (SH)), and in 22 patients with normal tendons. US findings were compared with clinical, laboratory, and radiologic results. In patients with FH, typical xanthomas in the form of hyperechoic tendinal tumors were found in only 15% while various forms of inhomogeneity of tendon structure without xanthoma formation were found in 75%. The high rate of tendon inhomogeneity may be due to the concomitant occurrence of both xanthomas and degeneration of tendon fibers. Physical examination revealed abnormalities in 60% of these patients. At CT of the tendons, abnormalities were found in 65% of the FH patients and in 40%, abnormalities were shown by plain radiography. In SH, the results did not differ significantly from normal controls. In our opinion US should be used to prove or rule out Achilles tendon abnormalities in patients with FH for prophylaxis and treatment of tendinitis and tendon rupture.

Lipids, adiposity and tendinopathy: is there a mechanistic link? Critical review

Being overweight or obese is associated with an elevated risk of tendon pathology. However, for sportspeople the epidemiological data linking weight or adiposity on one hand, and risk of tendon pathology on the other, are less consistent. Indeed, the mechanistic links between diet, adiposity and tendon pathology remain largely unexamined. Recent studies have begun to examine the effects of dietary interventions on outcomes such as tendon biomechanics or pain. Oxidised low-density lipoprotein has been shown to (A) accumulate in the tendon tissues of mice that eat a fatty diet and (B) induce a pathological phenotype in human tendon cells. This paper addresses the current debate: is excessive body mass index (causing increased load and strain on tendon tissue) per se the underlying mechanism? Or do local or systemic influences of fat on tendons predispose to tendon pathology? This narrative review argues that excessive blood lipids may be an important avenue for clinical investigations.

Bilateral spontaneous and simultaneous rupture of the Achilles tendons secondary to exercises for limb ischemia: A case report

Exercise is proven to be safe and effective treatment and is prescribed routinely for the conservative management of intermittent claudication. Before advising about the exercises, the assessment of these patients rarely includes risk factors for the Achilles tendon rupture. We present a case report of bilateral simultaneous and spontaneous rupture of the Achilles tendons secondary to the exercises prescribed for intermittent claudication in a patient with significant risk factors for Achilles rupture.

Pathogenesis, detection and treatment of Achilles tendon xanthomas

Tendon xanthomatosis often accompanies familial hypercholesterolaemia, but it can also occur in other pathologic states. Achilles tendons are the most common sites of tendon xanthomas. Low-density lipoprotein (LDL) derived from the circulation accumulates into tendons. The next steps leading to the formation of Achilles tendon xanthomas (ATX) are the transformation of LDL into oxidized LDL (oxLDL) and the active uptake of oxLDL by macrophages within the tendons. Although physical examination may reveal Achilles tendon xanthomas (ATX), there are several imaging methods for their detection. It is worth mentioning that ultrasonography is the method of choice in everyday clinical practice. Although several treatments for Achilles tendon xanthomas (ATX) have been proposed (LDL apheresis, statins, etc.), they target mostly in the treatment of the basic metabolic disorder of lipid metabolism, which is the main cause of these lesions. In this review we describe the formation, detection, differential diagnosis and treatment of ATX as well as the relationship between tendon xanthomas and atheroma.

Achilles tendon injuries in athletes

Two-thirds of Achilles tendon injuries in competitive athletes are paratenonitis and one-fifth are insertional complaints (bursitis and insertion tendinitis). The remaining afflictions consist of pain syndromes of the myotendineal junction and tendinopathies. The majority of Achilles tendon injuries from sport occur in males, mainly because of their higher rates of participation in sport, but also with tendinopathies a gender difference is probably indicated. Athletes in running sports have a high incidence of Achilles tendon overuse injuries. About 75% of total and the majority of partial tendon ruptures are related to sports activities usually involving abrupt repetitive jumping and sprinting movements. Mechanical factors and a sedentary lifestyle play a role in the pathology of these injuries. Achilles tendon overuse injuries occur at a higher rate in older athletes than most other typical overuse injuries. Recreational athletes with a complete Achilles tendon rupture are about 15 years younger than those with other spontaneous tendon ruptures. Following surgery, about 70 to 90% of athletes have a successful comeback after Achilles tendon injury. Surgery is required in about 25% of athletes with Achilles tendon overuse injuries and the frequency of surgery increases with patient age and duration of symptoms as well as occurrence of tendinopathic changes. However, about 20% of injured athletes require a re-operation for Achilles tendon overuse injuries, and about 3 to 5% are compelled to abandon their sports career because of these injuries. Myotendineal junction pain should be treated conservatively. Partial Achilles tendon ruptures are primarily treated conservatively, although the best treatment method of chronic partial rupture seems to be surgery. Complete Achilles tendon ruptures of athletes are treated surgically, because this increases the likelihood of athletes reaching preinjury activity levels and minimises the risk of re-ruptures. Marked forefoot varus is found in athletes with Achilles tendon overuse injuries, reflecting the predisposing role of ankle joint overpronation. Athletes with the major stress in lower extremities have often a limited range of motion in the passive dorsiflexion of the ankle joint and total subtalar joint mobility, which seems to be predisposing factor for these injuries. Various predisposing transient factors are found in about one-third of athletes with Achilles tendon overuse injuries; of these, traumatic factors (mostly minor injuries) predominate. The typical histological features of chronically inflamed paratendineal tissue of the Achilles tendon are profound proliferation of loose, immature connective tissue and marked obliterative and degenerative alterations in the blood vessels. These changes cause continuing leakage of plasma proteins, which may have an important role in the pathophysiology of these injuries. The chronically inflamed paratendineal tissues of the Achilles tendon do not seem to have enough capacity to form mature connective tissue.

Ultrasonography of achilles tendons in primary hypercholesterolemia. Comparison with computed tomography

Tendon xanthoma are a hallmark of familial hypercholesterolemia and are among its earliest clinical manifestations. Achilles tendon size, advanced to a generally accepted marker, is virtually specific for the disease and easily accessible for measurement. Hypercholesterolemic patients with coronary heart disease have been reported to have larger diameters of the Achilles tendons than patients without coronary problems. Furthermore, Achilles tendon xanthomas have been shown to regress with treatment of the lipid disorder. Mainly radiological procedures were applied in the past to evaluate the diameters of the Achilles tendon but their use is limited by radiation protection. We have used real-time ultrasonography to evaluate the Achilles tendons of 38 patients with primary hypercholesterolemia and 32 normocholesterolemic controls. The anterior posterior diameter in the patients was 13.4 +/- 5.9 mm (range 6-20 mm) and 5.7 +/- 0.7 mm (range 5-8 mm) in the control group. In 8 patients with newly diagnosed and previously untreated hypercholesterolemia the thickness correlated highly with their age. The Achilles tendons in about half of the patients (n = 21) showed a homogeneous thickening, whereas the others revealed an inhomogeneous thickening indicating the presence of circumscribed xanthoma. Upon comparison of the ultrasonographic procedure with an established method (computed tomography) in 18 patients and 8 normal volunteers a highly significant correlation (r = 0.96) proved the validity of the sonography. We show that real time ultrasonography is a valid procedure to assess Achilles tendon diameters in patients with primary hypercholesterolemia. It can be applied frequently and may be useful to follow xanthoma regression during lipid lowering treatment.

Bilateral rupture of the Achilles tendon in patients on steroid therapy

Three patients are presented who sustained bilateral rupture of the Achilles tendon while on systemic steroid therapy for chest disease; a fourth patient with polymyalgia rheumatica on steroids is also presented. This is further evidence that tendon rupture can be a direct complication of steroid treatment. The English-language literature on bilateral Achilles tendon rupture is reviewed.