Longitudinal tears of both peroneal tendons associated with tophaceous gouty infiltration. A case report

Impact of Dual-Energy Computed Tomography (DECT) Postprocessing Protocols on Detection of Monosodium Urate (MSU) Deposits in Foot Tendons of Cadavers

OBJECTIVE

To evaluate two different dual-energy computed tomography (DECT) post-processing protocols for the detection of MSU deposits in foot tendons of cadavers with verification by polarizing light microscopy as the gold standard.

MATERIAL AND METHODS

A total of 40 embalmed cadavers (15 male; 25 female; median age, 82 years; mean, 80 years; range, 52-99; SD ± 10.9) underwent DECT to assess MSU deposits in foot tendons. Two postprocessing DECT protocols with different Hounsfield unit (HU) thresholds, 150/500 (=established) versus 120/500 (=modified). HU were applied to dual source acquisition with 80 kV for tube A and 140 kV for tube B. Six fresh cadavers (4 male; 2 female; median age, 78; mean, 78.5; range 61-95) were examined by DECT. Tendon dissection of 2/6 fresh cadavers with positive DECT 120 and negative DECT 150 studies were used to verify MSU deposits by polarizing light microscopy.

RESULTS

The tibialis anterior tendon was found positive in 57.5%/100% (DECT 150/120), the peroneus tendon in 35%/100%, the achilles tendon in 25%/90%, the flexor halluces longus tendon in 10%/100%, and the tibialis posterior tendon in 12.5%/97.5%. DECT 120 resulted in increased tendon MSU deposit detection, when DECT 150 was negative, with an overall agreement between DECT 150 and DECT 120 of 80% (p = 0.013). Polarizing light microscope confirmed MSU deposits detected only by DECT 120 in the tibialis anterior, the achilles, the flexor halluces longus, and the peroneal tendons.

CONCLUSION

The DECT 120 protocol showed a higher sensitivity when compared to DECT 150.

Asymptomatic Hyperuricemia Is Associated with Achilles Tendon Rupture through Disrupting the Normal Functions of Tendon Stem/Progenitor Cells

Hyperuricemia is a metabolic disorder that is essential to the development of inflammatory gout, with increasing prevalence over recent years. Emerging clinical findings has evidenced remarkable tendon damage in individuals with longstanding asymptomatic hyperuricemia, yet the impact of hyperuricemia on tendon homeostasis and associated repercussions is largely unknown. Here, we investigated whether asymptomatic hyperuricemia was associated with spontaneous ruptures in the Achilles tendon and the pathological effect of hyperuricemia on the tendon stem/progenitor cells (TSPCs). Significantly higher serum uric acid (SUA) levels were found in 648 closed Achilles tendon rupture (ATR) patients comparing to those in 12559 healthy volunteers. In vitro study demonstrated that uric acid (UA) dose dependently reduced rat Achilles TSPC viability, decreased the expressions of tendon collagens, and deformed their structural organization while significantly increased the transcript levels of matrix degradative enzymes and proinflammatory factors. Consistently, marked disruptions in Achilles tendon tissue structural and functional integrity were found in a rat model of hyperuricemia, together with enhanced immune cell infiltration. Transcriptome analysis revealed a significant elevation in genes involved in metabolic stress and tissue degeneration in TSPCs challenged by hyperuricemia. Specifically, reduced activity of the AKT-mTOR pathway with enhanced autophagic signaling was confirmed. Our findings indicate that asymptomatic hyperuricemia may be a predisposition of ATR by impeding the normal functions of TSPCs. This information may provide theoretical and experimental basis for exploring the early prevention and care of ATR.

Peroneus brevis tendon injuries: Report of two cases and review of literature

The incidence of peroneal tendon disorders in the population is unknown and they are usually overlooked. We report two cases of peroneus brevis injuries and a comprehensive literature review was performed. The first case was a 53-year-old man presented with persistent pain on the lateral aspect on the left ankle during the last four years and difficulty to bear weight during the last year. MRI showed longitudinal tear of peroneus brevis tendon and the patient underwent surgical treatment. The second case was a 46-year-old woman with persistent pain on the lateral aspect of the ankle with a history of a road traffic accident two years ago. Although MRI showed a peroneus brevis tendon tear, this was a false positive finding. Surgical treatment revealed no tear and symphysiolysis managed to relieve patient's symptoms. Even though MRI is the most effective diagnostic tool in depicting peroneal tendon injuries, there are false positive findings. In cases when symptoms persist, surgical exploration is indicated.

[Peroneal tendon pathologies : From the diagnosis to treatment]

Peronealsehnenpathologien sind selten, jedoch häufig unterdiagnostiziert. Eine Assoziation mit einer chronisch lateralen Sprunggelenkinstabilität sowie mit einer varischen Rückfußachse kann bestehen. Pathologien der Sehnen lassen sich in 3 Kategorien einteilen: Tendinitis und Tenosynovitis, Sehnenrisse und Rupturen sowie Sehnensubluxation und Sehnenluxation. Die Magnetresonanztomographie ist die Standardmethode zur radiologischen Beurteilung. Die Diagnose und Behandlung basieren jedoch in erster Linie auf Anamnese und klinischer Untersuchung. Eine primär konservative Therapie kann versucht werden, ausgenommen bei Peronealsehnenluxationen des professionellen Sportlers. Die chirurgische Therapie sollte gezielt auf die zugrunde liegende Pathologie abgestimmt werden und kann dementsprechend divers von der tendoskopischen Synovektomie bis zur anatomischen Reparatur des superioren peronealen Retinakulums mit Vertiefung der retromalleolären Rinne ausfallen. Die postoperativen Ergebnisse zeigen eine hohe Patientenzufriedenheit und niedrige Reluxationsraten.

[Analysis of the effect of asymptomatic hyperuricemia on the effectiveness after arthroscopic rotator cuff repair]

Objective

To investigate the effect of asymptomatic hyperuricemia on the effectiveness of arthroscopic rotator cuff repair.

Methods

The clinical data of 80 patients who underwent arthroscopic rotator cuff repair and met the selection criteria between March 2018 and December 2019 were retrospectively analyzed. According to the serum uric acid level, the patients were divided into hyperuric acid group (46 cases, the serum uric acid level was more than 417 μmol/L in males and was more than 357 μmol/L in females) and normal group (34 cases, serum uric acid level was lower than the above standard). There was no significant difference in gender, age, side, body mass index, blood glucose level, total cholesterol level, rotator cuff tear size, and preoperative shoulder motion, visual analogue scale (VAS) score, University of California-Los Angeles (UCLA) score, Constant score, American Shoulder and Elbow Surgeons (ASES) score, and other general data between the two groups ( P>0.05). The range of motion of abduction, forward flexion, and external rotation at 90° abduction were recorded and compared between the two groups before operation and at last follow-up; the improvement of shoulder pain was evaluated by VAS score; the improvement of shoulder function was evaluated by UCLA score, Constant score, and ASES score; and the shoulder joint MRI grade was evaluated according to Sugaya evaluation criteria.

Results

All patients were followed up 9-16 months, with an average of 11.9 months; there was no significant difference in the follow-up time between the two groups ( t=0.968, P=0.336). There were 2 cases of retear in the hyperuric acid group (including 1 case of severe tear) and 1 case of light retear in the normal group. The remaining patients in the two groups had no early-related complications. At last follow-up, the range of motion of the shoulder joints (abduction, forward flexion, external rotation at 90° abduction), VAS score, UCLA score, Constant score, and ASES score of the two groups were significantly improved when compared with preoperative ones ( P<0.05); the above indicators in the normal group were significantly better than those in the hyperuric acid group ( P<0.05). The MRI grade of the shoulder joint in the normal group was significantly better than that in the hyperuric acid group ( Z=-2.000, P=0.045).

Conclusion

Compared with patients with normal serum uric acid level, asymptomatic hyperuricemia can lead to worse recovery after arthroscopic rotator cuff repair in patients with rotator cuff tears.

Lesions of the heel fat pad

OBJECTIVE

The heel fat pad (HFP) is a specialized soft tissue structure formed of adipose tissue that overlies the inferior and posterior aspect of the calcaneus and provides the cushioning effect of the heel. Lesions of the HFP are rare and can be a cause of debilitating heel pain that may often pose a challenge to clinicians. This study provides a series of lesions identified within the HFP.

METHODS AND MATERIALS

A retrospective review of heel pad lesions over a 12 year period was conducted at our tertiary orthopaedic oncology centre. All lesions of the heel fat pad were included in the study. Plantar fasciitis was excluded.

RESULTS

There were 17 heel pad lesions identified, of which the majority (n = 15) were benign.

CONCLUSION

We highlight a wide spectrum of pathologies that can occur in the HFP. Although rare, clinicians should be aware of these lesions, to initiate appropriate management.

Gouty Achilles Tendinopathy: A Case Report

Tendinopathy in the presence of gouty arthropathy is relatively common, yet the clinical suspicion for gout involvement in acute tendon pain remains low. A 49-year-old man presented with an acute, tender, erythematous mass to the right posterior heel. A computed tomographic scan was obtained, which revealed a septated fluid collection superficial to the Achilles tendon. The patient was taken to the operating room for an incision and drainage with debridement, and the abscess was found to be filled with caseous material. The diagnosis of gout was confirmed with pathology. The calcaneus was submitted to biopsy, and the results were negative for osteomyelitis. The patient was returned to the operating room for repair of the Achilles tendon with flexor hallucis longus tendon transfer. Postoperatively, the patient was nonweightbearing for 6 weeks. Oral colchicine was used perioperatively, and a steroid taper was administered. The patient was started on allopurinol and colchicine for chronic treatment. At 14 months, the patient was walking without pain or recurrence of the mass. Although the relationship between hyperuricemia and tendinopathy is not completely understood, it is apparent that tendon involvement may be a sequela in patients with gout. When a patient presents with acute tendon pain, gout should be considered in the differential diagnosis.

An Untypical Case of Gouty Infiltration of Both Peroneal Tendons and a Longitudinal Lesion of the Peroneus Brevis Tendon Mimicking Synovial Sarcoma

We present a case of a 70-year-old male patient with an untypical gout infiltration of the peroneal tendons mimicking synovial sarcoma. The patient had a negative history of gout at initial presentation in our department. Magnetic resonance imaging of the region revealed a finding highly suspicious for synovial sarcoma of the peroneal tendons. Open biopsy was performed. Histopathological examination of the tissue samples demonstrated the presence of gout with no signs of malignancy. The gout infiltration was excised in a subsequent surgery. Orthopedic surgeons should be aware of the potential manifestation of gout in tendons and bear this in mind in the differential diagnosis of soft tissue tumors.

A Case of a Second Intermetatarsal Space Gouty Tophus with a Presentation Similar to a Morton's Neuroma

Non-infectious soft tissue lesions of the foot and ankle are relatively rare clinically. These include benign and malignant neoplasms, as well as non-neoplastic or pseudotumoral lesions such as ganglionic, synovial and epidermoid cysts, intermetatarsal and adventitious bursitis, inflammatory lesions like gouty tophi and rheumatoid nodules, Morton’s neuroma, and granuloma annulare.

A 48-year-old male with a history of medically treated tophaceous gout presented with left foot neuropathic pain and paresthesia, in the setting of a well-circumscribed soft tissue lesion of the second intermetatarsal space, suspected to be a Morton’s neuroma. Magnetic resonance imaging (MRI) showed a 4.1 x 2.7 x 2.6 cm heterogeneous soft tissue mass containing multiple cystic areas. Excisional biopsy was performed and histologic examination revealed well-circumscribed nodules of amorphous material containing needle-shaped clefts, rimmed by histiocytes, and multinucleated giant cells consistent with a gouty tophus.

This is the first case reported in the literature of an intermetatarsal gouty tophus causing neuropathic pain and paresthesia. While Morton’s neuroma is the most common cause of this presentation, this case illustrates that other pseudotumoral lesions, such as a gouty tophus, may present similarly, and should be considered in the differential diagnosis. While most cases of tophaceous gout can be adequately treated with urate-lowering therapy, surgery may be indicated for tophi that do not resolve with medical treatment based upon symptom severity, compression of nearby structures, and functional impairment.

Electromyography comparison of the effects of various footwear in the activity patterns of the peroneus longus and brevis muscles

BACKGROUND

Peroneus longus and brevis (PLB) disorders are commonly in people with lateral ligamentous instability, ankle pain, lateral hindfoot pain and structures of the proximal compartment of the lower legs and their muscle activity is believed to be influenced by different footwear types. The proposal of this research is to evaluate the effects of five types of footwear with respect to the barefoot condition and analyze the activity patterns of PLB muscles in healthy subjects during the gait cycle.

METHODS

Thirty healthy subjects were recruited in a laboratory in this cross-sectional research design. While walking, electromyography (EMG) activity was measured from PLB via surface electrodes in six experimental conditions: 1) barefoot, 2) minimalist, 3) pronated control, 4) air chamber, 5) ethyl-vinyl-acetate (EVA) and 6) boost. These data were obtained and compared.

RESULTS

The peroneus brevis showed significant reductions in the peak amplitude of the five footwear types (minimalist, pronation control, air chamber, EVA and boost) with respect to the barefoot condition in the propulsion phase of the gait cycle during walking (P = 0.034; P < 0.001; P < 0.001; P < 0.001; P = 0.006) and running (P = 0.004; P < 0.001; P = 0.001; P < 0.001; P = 0.001), respectively. Furthermore, peroneus longus showed significant reductions in the peak amplitude of these five footwear types with respect to the barefoot condition in the propulsion phase of the gait cycle during running (P = 0.005; P = 0.038; P = 0.019; P = 0.025; P = 0.021).

CONCLUSION

The EMG activity patterns of the PLB muscles may depend on the use of different types of sport shoes such as minimalist, pronation control, air chamber, EVA and boost footwear with respect the barefoot condition in different phases of the gait cycle during walking and running.

Bilateral First-Ray Amputation of the Foot Due to Severe Tophaceous Gout Complicated by Infection and Discharged Sinus A Case Report

BACKGROUND

Gout is a purine metabolism disease. Tophaceous gout may cause joint destruction and other systemic problems and sometimes may be complicated by infection. Infection and sinus with discharge associated with tophaceous gout are serious complications, and treatment is difficult. We present a patient with tophaceous gout complicated by infection and discharging sinus treated by bilateral amputation at the level of the first metatarsus.

METHODS

A 43-year-old man previously diagnosed as having gout, and noncompliant with treatment, presented with tophaceous gout associated with discharging sinus and infection on his left first metatarsophalangeal joint. Because of the discharging sinus associated with the tophaceous deposits, the soft-tissue and bony defects, and the noncompliance of the patient, amputation of the first ray was undertaken, and a local plantar fasciocutaneous flap was used to close the defect. After 8 months, the patient was admitted to the emergency department with similar symptoms in his right foot, and the same surgical procedure was performed.

RESULTS

One year after the second surgery, the patient had no symptoms, there was no local inflammatory reaction over the surgical areas, and laboratory test results were normal.

CONCLUSIONS

Gout disease with small tophi often can be managed conservatively. However, in patients with extensive lesions, risk of superinfection justifies surgical treatment. Results of complicated cases are not without morbidity; therefore, early surgical treatment may prevent extremity loss and further complications. In severe cases, especially with compliance issues, amputation provides acceptable results.

Gout Can Increase the Risk of Receiving Rotator Cuff Tear Repair Surgery

BACKGROUND

Gout commonly involves joint inflammation, and clinical epidemiological studies on involved tendons are scant. Rotator cuff tears are the most common cause of shoulder disability, and surgery is one of the choices often adopted to regain previous function.

PURPOSE

To investigate the risk of receiving rotator cuff repair surgery among patients with gout and to analyze possible risk factors to design an effective prevention strategy.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The authors studied a 7-year longitudinal follow-up of patients from the Taiwan Longitudinal Health Insurance Database 2005 (LHID2005). This included a cohort of patients who received a diagnosis of gout during 2004-2008 (gout cohort) and a cohort matched by propensity scores (control cohort). A 2-stage approach that used the National Health Interview Survey 2005 was used to obtain missing confounding variables from the LHID2005. The crude hazard ratio (HR) and adjusted HR were estimated between the gout and control cohorts.

RESULTS

The gout and control cohorts comprised 32,723 patients with gout and 65,446 people matched at a ratio of 1:2. The incidence of rotator cuff repair was 31 and 18 per 100,000 person-years in the gout and control cohorts, respectively. The crude HR for rotator cuff repair in the gout cohort was 1.73 (95% confidence interval [CI], 1.23-2.44; P < .01) during the 7-year follow-up period. After adjustment for covariates by use of the 2-stage approach, the propensity score calibration-adjusted HR was 1.60 (95% CI, 1.12-2.29; P < .01) in the gout cohort. Further analysis revealed that the adjusted HR was 1.73 (95% CI, 1.20-2.50; P < .001) among patients with gout who did not take hypouricemic medication and 2.70 (95% CI, 1.31-5.59; P < .01) for patients with gout aged 50 years or younger.

CONCLUSION

Patients with gout, particularly those aged 50 years or younger and without hypouricemic medication control, are at a relatively higher risk of receiving rotator cuff repair surgery. Strict control of uric acid levels with hypouricemic medication may effectively reduce the risk of rotator cuff repair.

Limitation of magnetic resonance imaging in diagnosing longitudinal peroneal tendon tears

The purpose of this case study was to highlight a potential limitation of magnetic resonance imaging in diagnosing longitudinal tendon tears and to emphasize the importance of clinical examination for peroneal tendinopathy. We describe a 15-year-old female with lateral ankle pain, who was negative for peroneal tendon tear on magnetic resonance imaging. Owing to high clinical suspicion of peroneal tendon pathology, we opted to take the patient to the operating room and found a 6.5-cm longitudinal tear and a low-lying muscle belly of the peroneus brevis tendon. A low-lying muscle belly of the peroneal tendon has been shown to be associated with increased tendon tears.

Relevant aspects of imaging in the diagnosis and management of gout

Gout is an inflammatory arthritis characterized by the deposition of monosodium urate crystals in the synovial membrane, articular cartilage and periarticular tissues leading to inflammation. Men are more commonly affected, mainly after the 5th decade of life. Its incidence has been growing with the population aging. In the majority of the cases, the diagnosis is made by clinical criteria and synovial fluid analysis, in search for monosodium urate crystals. Nonetheless, gout may sometimes have atypical presentations, complicating the diagnosis. In these situations, imaging methods have a fundamental role, aiding in the diagnostic confirmation or excluding other possible differential diagnosis. Conventional radiographs are still the most commonly used method in gout patients' evaluation; nevertheless, this is not a sensitive method, since it detect only late alterations. In the last years, there have been several advances in imaging methods for gout patients. Ultrasound has shown a great accuracy in the diagnosis of gout, identifying monosodium urate deposits in the synovial membrane and articular cartilage, in detecting and characterizing tophi and in identifying tophaceous tendinopathy and enthesopathy. Ultrasound has also been able to show crystal deposition in patients with articular pain in the absence of a classical gout crisis. Computed tomography is an excellent method for detecting bone erosions, being useful in spine involvement. Dual-energy CT is a new method able to provide information about the chemical composition of tissues, with high accuracy in the identification of monosodium urate deposits, even in the early stages of the disease and in cases of difficult characterization. Magnetic resonance imaging is useful in the evaluation of deep tissues not accessible by ultrasound. Besides the diagnosis, with the emergence of new drugs that aim to reduce tophaceous burden, imaging methods have become useful tools in monitoring the treatment of patients with gout.

Surgical Management of Gout in the Foot and Ankle A Systematic Review

BACKGROUND

The surgical management of tophaceous gout has been well documented in the literature, including its effect on foot pain and disability. To date, there have been no systematic reviews assessing the quality of the literature relating to the operative management of tophaceous gout and the outcomes in the foot and ankle.

METHODS

The following electronic databases were searched (1980-2014): Allied and Complementary Medicine, Cumulative Index to Nursing and Allied Health Literature, MEDLINE, Scopus, and the Cochrane Library. The articles identified were published in English and included adult participants (age ≥18 years) with diagnosed gout and surgical intervention to the foot and ankle. The Downs and Black Quality Index was modified to assess the quality of the articles being reviewed.

RESULTS

Six articles were reviewed and were of moderate quality (mean quality score of 71%). Surgical management was conducted on men (88%) with a mean age of 52 years. There was wide variation in the types of surgical procedures performed, with 28% of studies reporting surgery to the first metatarsophalangeal joint. Most studies were retrospective. A wide range of outcome measures were reported: foot pain, function, preoperative and postoperative activity levels, monitoring of uric acid levels, and patient satisfaction after surgery.

CONCLUSIONS

The review demonstrated a limited number of good-quality studies. Several surgical procedures for the foot and ankle in people with chronic tophaceous gout were reported. Future studies should include prospective observational studies using validated and reliable patient-reported outcome measures.

Foot and ankle muscle strength in people with gout: A two-arm cross-sectional study

BACKGROUND

Foot and ankle structures are the most commonly affected in people with gout. However, the effect of gout on foot and ankle muscle strength is not well understood. The primary aim of this study was to determine whether differences exist in foot and ankle muscle strength for plantarflexion, dorsiflexion, inversion and eversion between people with gout and age- and sex-matched controls. The secondary aim was to determine whether foot and ankle muscle strength was correlated with foot pain and disability.

METHODS

Peak isokinetic concentric muscle torque was measured for ankle plantarflexion, dorsiflexion, eversion and inversion in 20 participants with gout and 20 matched controls at two testing velocities (30°/s and 120°/s) using a Biodex dynamometer. Foot pain and disability was measured using the Manchester Foot Pain and Disability Index (MFPDI).

FINDINGS

Participants with gout demonstrated reduced muscle strength at both the 30°/s and 120°/s testing velocities for plantarflexion, inversion and eversion (P<0.05). People with gout also displayed a reduced plantarflexion-to-dorsiflexion strength ratio at both 30°/s and 120°/s (P<0.05). Foot pain and disability was higher in people with gout (P<0.0001) and MFPDI scores were inversely correlated with plantarflexion and inversion muscle strength at the 30°/s testing velocity, and plantarflexion, inversion and eversion muscle strength at the 120°/s testing velocity (all P<0.05).

INTERPRETATION

People with gout have reduced foot and ankle muscle strength and experience greater foot pain and disability compared to controls. Foot and ankle strength reductions are strongly associated with increased foot pain and disability in people with gout.

Rehabilitation after surgical treatment of peroneal tendon tears and ruptures

PURPOSE

The purpose of this study was to provide an overview of the available evidence on rehabilitation programmes after operatively treated patients with peroneal tendon tearsand ruptures.

METHODS

A systematic review was performed, and PubMed and EMBASE were searched for relevant studies. Information regarding the rehabilitation programme after surgical management of peroneal tendon tears and ruptures was extracted from all included studies.

RESULTS

In total, 49 studies were included. No studies were found with the primary purpose to report on rehabilitation of surgically treated peroneal tendon tears or ruptures. The median duration of the total immobilization period after primary repair was 6.0 weeks (range 0-12), 7.0 weeks (range 3.0-13) after tenodesis, 6.3 weeks (range 3.0-13) after grafting, and 8.0 weeks (range 6.0-11) after end-to-end suturing. Forty one percent of the studies that reported on the start of range of motion exercises initiated range of motion within 4 weeks after surgery. No difference was found in duration of immobilization or start of range of motion between different types of surgical treatment options.

CONCLUSION

Appropriate directed rehabilitation appears to be an important factor in the clinical success of surgically treated peroneal tendon tears and ruptures. There seems to be a trend towards shorter immobilization time and early range of motion, although there is no consensus in the literature on best practice recommendations for optimizing rehabilitation after surgical repair of peroneal tendon tears or ruptures. It is important to adjust the rehabilitation protocol to every specific patient for an optimal rehabilitation.

LEVEL OF EVIDENCE

Systematic Review, Level IV.

Endoscopic Resection of Avulsed Fragment of Tibial Tuberosity and Endoscopic-Assisted Repair of Patellar Tendon

An avulsion fracture of part of the tibial tuberosity can occur as a result of a tophaceous tuberosity or Osgood-Schlatter disease. We describe an endoscopic technique of debridement, bone fragment resection, and tendon repair. This technique has the potential advantage of fewer wound complications. It is performed through proximal and distal portals on the sides of the patellar tendon. The working space is deep to the tendon. After debridement of the tendon and resection of the bone fragment, the tendon gap is assessed. Endoscopic-assisted side-by-side repair is performed to close the gap if the gap is less than 30% of the width of the tendon. If the gap is more than 30% of the width of the tendon, the proximal stump of the avulsed tendon can be retrieved through the proximal portal. Krackow suture with stay stitches is applied to the proximal stump. The stump is put back and sutured to the tibial insertion through a bone tunnel or suture anchor. This is augmented by side-by-side suturing of the avulsed tendon with the adjacent normal tendon.

Endoscopic Resection of Gouty Tophus of the Patellar Tendon

Tophaceous deposition of tendon can result in spontaneous patellar tendon rupture. Surgical therapy may be needed to control symptoms and prevent tendon rupture. Open debridement of the lesion requires a lengthy incision over the lesion; this may result in symptomatic scar adhesion of the patellar tendon or an unhealed wound with persistent tophaceous discharge. Moreover, the other part of the patellar tendon cannot be examined through the incision. We describe a technique for endoscopic resection of a gouty tophus of the patellar tendon. It has the advantage of small incisions away from the lesion and tendon and minimizes wound problems. The whole patellar tendon can be examined endoscopically.

The radiographic and MRI features of gout referred as suspected soft tissue sarcoma: a review of the literature and findings from 27 cases

Gout has been termed the "great mimicker", for its ability to resemble other pathological conditions. Whilst the typical imaging features of gout are well described, there is a relative paucity of literature describing more challenging cases of gout, where a malignant tumour has been considered in the differential diagnosis. The aim of this article is to provide an overview of the radiographic and MRI features of 27 cases of gout that were initially referred to our centre as suspected soft tissue sarcoma, alongside a review of the literature.

Multiple tendon ruptures of unknown etiology

Tendon ruptures are common findings in foot and ankle practice. The etiology of tendon ruptures tends to be multifactorial-usually due to a combination of trauma, effects of systemic diseases, adverse effects of medications, and obesity. We present an unusual case of right Achilles tendinitis, left Achilles tendon rupture, bilateral peroneus longus tendon rupture, and left peroneus brevis tendon rupture of unknown etiology. This case report highlights the need for research for other possible, lesser known etiologies of tendon pathology.

LEVEL OF EVIDENCE

Therapeutic, Level IV, Case Study.

Intratendinous gouty tophus mimics patellar tendonitis in an athlete

We describe the imaging and pathologic features of a case of intratendinous patellar gouty tophus incidentally discovered in a patient with knee pain. The possibility of intratendinous gouty tophus must be kept in mind by sports physicians, especially in the management of patellar tendinopathy in athletes. It may be associated with other injuries, such as enthesopathies or partial tendon tears.

Tendon involvement in the feet of patients with gout: a dual-energy CT study

OBJECTIVES

To examine the frequency and patterns of monosodium urate (MSU) crystal deposition in tendons and ligaments in patients with gout using dual-energy CT (DECT).

METHODS

Ninety-two patients with tophaceous gout had DECT scanning of both feet. Two readers scored the DECT scans for MSU crystal deposition at 20 tendon/ligament sites and 42 bone sites (total 1840 tendon/ligament sites and 3864 bone sites).

RESULTS

MSU crystal deposition was observed by both readers in 199/1840 (10.8%) tendon/ligament sites and in 399/3864 (10.3%) bone sites (p=0.60). The Achilles tendon was the most commonly involved tendon/ligament site (39.1% of all Achilles tendons), followed by the peroneal tendons (18.1%). Tibialis anterior and the extensor tendons were involved less commonly (7.6-10.3%), and the other flexor tendons, plantar fascia and deltoid ligaments were rarely involved (<5%) (p<0.0001 between sites). Involvement of the enthesis alone was more common in the Achilles tendon (OR (95% CI) 74.5 (4.4 to 1264), p<0.0001), as was any involvement of the enthesis (OR (95% CI) 6.8 (3.6 to 13.0), p<0.0001).

CONCLUSIONS

Tendons are commonly affected by MSU crystal deposition in patients with tophaceous gout. The patterns of MSU crystal deposition suggest that biomechanical strain or other local factors may contribute to deposition of MSU crystals.

Longitudinal tears of peroneus longus and brevis tendons: a gouty infiltration

The natural history of recurrent uric acid deposition includes joint destruction, as well as tendon weakening and rupture. Simultaneous rupture of the peroneus longus and brevis tendons secondary to tophaceous gout is very rare. In the present report, we describe the case of a 37-year-old man who had a history of recurrent ankle pain and 4 previous episodes of acute gout localized to his ipsilateral first metatarsophalangeal joint. The physical examination revealed the ankle pain to actually be localized to the peroneal tendons immediately distal to the fibular malleolar groove. Magnetic resonance imaging showed longitudinal tears in the peroneus longus and brevis. Surgical exploration and repair of the ruptured tendons revealed the presence of monosodium urate deposition within the substance of the tendons at the rupture sites. The tendons were debrided and repaired using longus to brevis tenodesis. The postoperative course was unremarkable and entailed referral to a rheumatologist for metabolic management. After more than a 1-year period of follow-up, the patient was ambulating without difficulties wearing regular shoe gear.

Ultrasound features of tophi in chronic tophaceous gout

OBJECTIVE

To describe the different and lesser-known ultrasound features of tophi in chronic tophaceous gout.

METHODS

Ultrasound images of 138 affected areas were analyzed from 31 patients with gout, using high-quality broadband linear transducers (frequency range of 8-14 MHz). Tophi were classified relative to echogenicity, echotexture, contours, number and the presence or absence of hypoechoic halo. The duration of illness was correlated with the presence of calcifications in tophi.

RESULTS

Hyperechoic tophi were seen in 133 areas (96.3%); these were most frequently hyperechoic and heterogeneous (37.6%) or hyperechoic and heterogeneous with calcification (32.6%). Contours were found to be poorly defined in 115 (83.3%) areas. Multiple grouped tophi were seen in 85 areas (61.6%) and 50 areas (36.2%) had individual tophi. In 77 examined areas (55.8%), there was a hypoechoic halo around the tophi. There was no correlation between illness duration and presence of calcifications on tophi.

CONCLUSIONS

Tophi are generally hyperechoic, heterogeneous, with poorly defined contours, multiple grouped and surrounded by an anechoic halo. Individual tophus and the absence of association between illness duration and the presence of calcification are newly described features. This study of tophaceous gout by ultrasound may contribute to the diagnostic elucidation of patients with clinically atypical gout and show its diverse characteristic forms of presentation.

Sonographic description and classification of tendinous involvement in relation to tophi in chronic tophaceous gout

Objective

To describe and classify the varied ultrasound features of tendinous involvement in relation to tophi in chronic tophaceous gout so that they are better recognised.

Methods

Ultrasound images of 138 affected areas from 31 patients with chronic tophaceous gout were analysed using high-quality broadband linear transducers. The relationship between tendon and tophi was classified, and the inter-observer agreement regarding classification was analysed.

Results

Tophi envelopment in the tendon was the most frequent characteristic (45%) followed by no relationship between tophi and tendon (41%), tophi at the insertion site of the tendon (7%), extrinsic compression (6%) and tophi within the tendon (1%). The inter-observer concordance on classification of the relationship between tophi and tendon was measured using McNemar’s test with P < 0.001 (χ² = 30.0, degree of freedom = 9) and kappa test = 0.627 (P < 0.001), indicating substantial inter-observer concordance.

Conclusion

Tophi generally envelope the tendon or there is no relationship between them. Tophi can also be found at the insertion site of the tendon, cause extrinsic compression or be located inside the tendon. There is substantial inter-observer agreement for ultrasound classification of tendon involvement by tophi. This study contributes to diagnostic elucidation and shows the diverse characteristic forms of tendon involvement by tophi.

Xanthomatous Infiltration of the Rotator Cuff and Long Head of Biceps with Rotator Cuff Tear in a Patient with Mixed Hyperlipidemia: A Case Report with MRI Imaging

Xanthomatous infiltration may rarely affect the rotator cuff muscles and long head of the biceps tendon. It is the deposition of cholesterol within the rotator cuff muscles and long head of the biceps tendon resulting from hyperlipidemia, specifically high triglyceride and total cholesterol levels. As more commonly seen with xanthomatous infiltration and tear of the Achilles tendon, there may also be an association with rotator cuff tendon deposition and tear. MRI images of xanthomatous infiltration with rotator cuff tear in a 77 year old man with hyperlipidemia are detailed in the following case report.

Rheumatic diseases presenting as sports-related injuries

Most individuals seeking consultation at sports medicine clinics are young, healthy athletes with injuries related to a specific activity. However, these athletes may have other systemic pathologies, such as rheumatic diseases, that may initially mimic sports-related injuries. As rheumatic diseases often affect the musculoskeletal system, they may masquerade as traumatic or mechanical conditions. A systematic review of the literature found numerous case reports of athletes who presented with apparent mechanical low back pain, sciatica pain, hip pain, meniscal tear, ankle sprain, rotator cuff syndrome and stress fractures and who, on further investigation, were found to have manifestations of rheumatic diseases. Common systemic, inflammatory causes of these musculoskeletal complaints include ankylosing spondylitis (AS), gout, chondrocalcinosis, psoriatic enthesopathy and early rheumatoid arthritis (RA). Low back pain is often mechanical among athletes, but cases have been described where spondyloarthritis, especially AS, has been diagnosed. Neck pain, another common mechanical symptom in athletes, can be an atypical presentation of AS or early RA. Hip or groin pain is frequently related to injuries in the hip joint and its surrounding structures. However, differential diagnosis should be made with AS, RA, gout, psudeogout, and less often with haemochromatosis and synovial chondochromatosis. In athletes presenting with peripheral arthropathy, it is mandatory to investigate autoimmune arthritis (AS, RA, juvenile idiopathic arthritis and systemic lupus erythematosus), crystal-induced arthritis, Lyme disease and pigmented villonodular synovitis. Musculoskeletal soft tissue disorders (bursitis, tendinopathies, enthesitis and carpal tunnel syndrome) are a frequent cause of pain and disability in both competitive and recreational athletes, and are related to acute injuries or overuse. However, these disorders may occasionally be a manifestation of RA, spondyloarthritis, gout and pseudogout. Effective management of athletes presenting with musculoskeletal complaints requires a structured history, physical examination, and definitive diagnosis to distinguish soft tissue problems from joint problems and an inflammatory syndrome from a non-inflammatory syndrome. Clues to a systemic inflammatory aetiology may include constitutional symptoms, morning stiffness, elevated acute-phase reactants and progressive symptoms despite modification of physical activity. The mechanism of injury or lack thereof is also a clue to any underlying disease. In these circumstances, more complete workup is reasonable, including radiographs, magnetic resonance imaging and laboratory testing for autoantibodies.

Intra-tendinous gout in a repaired flexor digitorum profundus

A patient presented with decreased flexion and triggering following a zone IIc flexor digitorum profundus repair 7 years previously. Chalky-white deposits, confirmed histologically as gout, were present at the repair site.

Operative treatment for peroneal tendon disorders

Peroneal tendon disorders are rare, are frequently missed, and can be a source of lateral ankle pain. Magnetic resonance imaging is the standard method of radiographic evaluation of peroneal tendon disorders; however, diagnosis and treatment are based primarily on the history and physical examination. Peroneal tenosynovitis typically responds to conservative therapy, and operative treatment is reserved for refractory cases. Operative treatment is frequently required for peroneal tendon subluxation and consists of anatomic repair or reconstruction of the superior peroneal retinaculum with or without deepening of the retromalleolar groove. Operative treatment of peroneal tendon tears is based on the amount of remaining viable tendon. Primary repair and tubularization is indicated for tears involving <50% of the tendon, and tenodesis is indicated for tears involving >50% of the tendon.

Metabolic diseases: gout

Gout is a disease of antiquity but is increasing once again in prevalence despite availability of reasonably effective treatments. This may be related to a combination of factors, including diet, obesity, and diuretic use. Allergic reactions, noncompliance, drug interactions, and sometimes inefficacy all limit the effective use of current hypouricemic agents. There are new treatments for gout on the horizon, including febuxostat, a nonpurine inhibitor of xanthine oxidase with a potentially better combination of efficacy and side effects than allopurinol. Diagnostic progress is being made in that ultrasound may offer a noninvasive means of diagnosing tophaceous deposits in and around joints. The increasing prevalence of gout means that dermatologists will see more cutaneous manifestations of gout, including tophi, draining sinus tracts, panniculitis, and dystrophic calcifications.