Musculoskeletal Injury Associated with Fluoroquinolone Antibiotics

Electrospun Aligned Nanofiber Yarns Constructed Biomimetic M-Type Interface Integrated into Precise Co-Culture System as Muscle-Tendon Junction-on-a-Chip for Drug Development

The incorporation of engineered muscle-tendon junction (MTJ) with organ-on-a-chip technology provides promising in vitro models for the understanding of cell-cell interaction at the interface between muscle and tendon tissues. However, developing engineered MTJ tissue with biomimetic anatomical interface structure remains challenging, and the precise co-culture of engineered interface tissue is further regarded as a remarkable obstacle. Herein, an interwoven waving approach is presented to develop engineered MTJ tissue with a biomimetic "M-type" interface structure, and further integrated into a precise co-culture microfluidic device for functional MTJ-on-a-chip fabrication. These multiscale MTJ scaffolds based on electrospun nanofiber yarns enabled 3D cellular alignment and differentiation, and the "M-type" structure led to cellular organization and interaction at the interface zone. Crucially, a compartmentalized co-culture system is integrated into an MTJ-on-a-chip device for the precise co-culture of muscle and tendon zones using their medium at the same time. Such an MTJ-on-a-chip device is further served for drug-associated MTJ toxic or protective efficacy investigations. These results highlight that these interwoven nanofibrous scaffolds with biomimetic "M-type" interface are beneficial for engineered MTJ tissue development, and MTJ-on-a-chip with precise co-culture system indicated their promising potential as in vitro musculoskeletal models for drug development and biological mechanism studies.

Floating patella: Ipsilateral and simultaneous rupture of the quadriceps and patellar tendons in a young individual (a surgical case report)

INTRODUCTION AND IMPORTANCE

The phenomenon of a floating patella or ipsilateral bifocal rupture of the extensor apparatus is an extremely rare injury, with few cases reported in the literature. The aim of this case study is to report an unprecedented event: the simultaneous trans-tendinous rupture of both quadriceps and patellar tendons in a young adult without predisposing factors, emphasizing the need for awareness in diagnosis and management, and suggesting a new avenue for research in prevention and rehabilitation.

CASE PRESENTATION

We report the case of a 35-year-old patient with no significant medical history, who experienced this injury following a sudden start in a sprint without prior warm-up. The clinical examination revealed a swollen, painful knee with active extension deficit, patellar ascent, and a sub patellar hiatus. Magnetic Resonance Imaging (MRI) confirmed a trans-tendinous rupture of both the patellar and quadriceps tendons.

CLINICAL DISCUSSION

Tendon repair was performed using end-to-end sutures and a figure-8 reinforcement with the semitendinosus tendon, along with gracilis plastie to strengthen the patellar tendon repair. This methodological approach is discussed in the context of its effectiveness and potential implications for future surgical management of similar injuries.

CONCLUSION

After a 12-month follow-up, the patient exhibited highly satisfactory results, resuming both professional and sporting activities. To our knowledge, this is the first published case of a trans-tendinous rupture of the extensor apparatus tendons. This observation serves as a reference in understanding the mechanism and surgical management of such lesions, emphasizing the need for further research and clinical vigilance in similar cases.

Urinary antibiotic exposure and low grip strength risk in community-dwelling elderly Chinese by gender and age

Emerging studies have shown that environmental contaminants were related to decreased handgrip strength. Nevertheless, no prior research has investigated the relationship of exposure to environmental antibiotics with grip strength. Thus, we explored the relationship between urinary antibiotic burden and grip strength among the elderly in China. This study consisted of 451 men and 539 women from the baseline survey of a cohort study. Commonly used antibiotics for humans and animals were detected in 990 urine samples through a biomonitoring method. Grip strength was measured by an electronic dynamometer. We examined the associations of antibiotic exposure with low grip strength (LGS), grip strength, and grip strength index, respectively. Results suggested that 34.9% of participants developed LGS, and 93.0% of individuals were exposed to 1-10 antibiotics. Among women, oxytetracycline (Quartile 2: odds ratio: 2.97, 95% confidence interval: 1.36-6.50), florfenicol (Quartile 3: 2.60 [1.28-5.27]), fluoroquinolones (Quartile 4: 1.88 [1.07-3.30]), and chloramphenicols (Quartile 3: 2.73 [1.35-5.51]) could enhance LGS risk. Among men, ofloxacin (Quartile 2: 3.32 [1.45-7.59]) increased LGS risk, whereas tetracycline (Quartile 2: 0.31 [0.11-0.88]) was implicated in reduced LGS risk. In participants < 70 years, ofloxacin (Quartile 2: 3.00 [1.40-6.42]) could increase LGS risk. For participants who were 70 years of age or older, veterinary antibiotics (Quartile 3: 1.73 [1.02-2.94]) were linked to a 73% increased risk of LGS. Our findings suggested that antibiotics mainly pertained to LGS, and there were gender and age disparities in associations between antibiotic exposure and muscle strength indicators in the elderly Chinese population.

Transosseous Repair With Nice Knot Augmentation Versus Knotless Suture Anchor Repair With Suture Tape for Quadriceps Tendon Rupture: A Cadaveric Study

Quadriceps tendon rupture is typically repaired using either transosseous tunnels or suture anchors. Recent literature has suggested that suture anchor repair is biomechanically superior to the use of transosseous tunnels. Augmentation of the transosseous technique with Nice knots may result in improved biomechanical properties as compared with a suture anchor construct. To compare biomechanical properties of a novel transosseous quadriceps tendon repair technique with Nice knot augmentation to those of knotless suture anchor repair, an artificial quadriceps tendon rupture was created in 10 matched pairs of cadaveric knees (n=20). Each cadaver was subjected to biomechanical testing to calculate the average ultimate load to failure, repair site gapping after early and late cyclic loading, and stiffness. Transosseous repair augmented with Nice knots as compared with knotless suture anchor repair had greater load to failure (mean±SD, 1489.5±297.6 N vs 717.7±191.4 N, P<.001), decreased gapping after early and late cyclic loading (cycles 1-20: mean±SD, 0.59±0.4 mm vs 2.1±1.2 mm, P=.008; cycles 21-250: mean±SD, 1.2±0.7 mm vs 3.9±1.7 mm, P=.002), and greater construct stiffness (mean±SD, 80.7±15.7 N/mm vs 44.4±13.4 N/mm, P=.001). The transosseous quadriceps tendon repair technique with Nice knot augmentation is biomechanically better than knotless suture anchor repair with regard to ultimate load to failure, gap formation after cyclic loading, and construct stiffness in cadaveric specimens. [Orthopedics. 202x;4x(x):xx-xx.].

Complex ruptures of the quadriceps tendon: a systematic review of surgical procedures and outcomes

Background

Chronic ruptures, ruptures following total knee arthroplasty (TKA), and re-ruptures of the quadriceps tendon (QT) are rare. A systematic review of the current literature was conducted on their treatment and outcome to provide evidence-based indications for their management.

Methods

We searched published articles in English on chronic ruptures of QT, QT ruptures that occurred after TKA, and re-ruptures in PubMed, Scopus, and Google Scholar up to January 2021. Twenty-five articles were included following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Results

Data from 25 articles (97 patients) with a mean age of 57 were retrieved. Patients were classified into three groups depending on the type of rupture: 16 patients suffered chronic QTR, 78 a QTR after a TKA, and 9 patients reported a re-rupture. The most frequent surgical approaches were different for each group: Codivilla’s Y-V technique and end-to-end sutures were the most commonly used in the chronic tears group (62.5%), synthetic MESH was the most frequent choice in QTR after a TKA group (38 patients, 53%), while end-to-end sutures were the first choice in the re-rupture group (4 patients, 44%).

Conclusions

Complex ruptures of the QT can be chronic ruptures, re-ruptures, or ruptures occurring after TKA. The choice of the best surgical technique depends on the macroscopic quality of the tendon stumps rather than the timing of intervention. Evidence-based preventive and therapeutic strategies should be developed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02696-9.

Outcomes following quadriceps tendon repair using transosseous tunnels versus suture anchors: A systematic review

INTRODUCTION

Two major techniques are used to repair complete quadriceps tendon ruptures, transosseous tunnel (TT) and the suture anchor (SA). There are multiple studies comparing the biomechanical outcomes of repairs performed with TT or SA. Our purpose was to compare the clinical outcomes following quadriceps tendon repair using SA and TT fixation techniques.

METHODS

Three major search engines were used with predetermined keyword searches to perform a systematic review of literature. These studies were independently scanned by two reviewers using PRISMA criterion. All included studies had to include at least one of the following outcome measures: range of motion (ROM), Lysholm score, complications, and/or re-ruptures.

RESULTS

Using three major search engines, 1039 articles were identified. After removing duplicates and screening for inclusion, 49 articles were reviewed. Two independent reviewers searched the studies to meet the inclusion criteria, and eight studies were selected. These eight studies included 156 knees in the TT group and 54 knees in the SA group. The TT group had a significantly better ROM after QT repair (132.5° versus 127.0°, p = 0.02). There was no significant difference in Lysholm scores between the TT group (92.6) and SA group (91.0, p = 0.11). There were significantly more complications in SA groups (9.3% versus 1.3%, p = 0.013), but not a significant difference in re-rupture rate between those undergoing SA vs. TT repair (3.7% versus 0%, p = 0.065). The SA group had a significantly higher age at time of surgery (63.62 vs. 54.32) CONCLUSION: The current study suggests that, following quadriceps tendon rupture, there are no significant differences in functional outcome between TT and SA techniques. Those undergoing TT repair attained a statistically significantly greater final ROM but this difference may not be clinically relevant. There was a statistically significantly higher rate of post-operative complications using SA technique.

Fluoroquinolone exposure in utero did not affect articular cartilage of resulting foals

BACKGROUND

Recent studies have shown that fluoroquinolones, specifically, enrofloxacin and its active metabolite (ciprofloxacin), cross the equine placenta without causing gross or histological lesions in the first and third trimester fetuses or resulting foal. However, it is possible that in utero exposure to fluoroquinolones may cause subtle lesions not detectable by standard means; thus, a more in-depth assessment of potential toxicity is warranted.

OBJECTIVES

To use quantitative magnetic resonance imaging (qMRI), biomechanical testing, and chondrocyte gene expression to evaluate the limbs of foals exposed to enrofloxacin during the third trimester of pregnancy.

STUDY DESIGN

In vivo and control terminal experiment.

METHODS

Healthy mares at 280 days gestation were assigned into three groups: untreated (n = 5), recommended therapeutic (7.5 mg/kg enrofloxacin, PO, SID, n = 6) or supratherapeutic (15 mg/kg, PO, SID, n = 6) doses for 14 days. Mares carried and delivered to term and nursed their foals for ~30 days. Two additional healthy foals born from untreated mares were treated post-natally with enrofloxacin (10 mg/kg PO, SID, for 5 days). By 30 days, foal stifles, hocks, elbows, and shoulders were radiographed, foals were subjected to euthanasia, and foal limbs were analysed by quantitative MRI, structural MRI, biomechanical testing and chondrocyte gene expression.

RESULTS

Osteochondral lesions were detected with both radiography and structural MRI in foals from both enrofloxacin-treated and untreated mares. Severe cartilage erosions, synovitis and joint capsular thickening were identified in foals treated with enrofloxacin post-natally. Median cartilage T2 relaxation times differed between joints but did not differ between treatment groups.

MAIN LIMITATIONS

A small sample size was assessed and there was no long-term follow-up.

CONCLUSION

While further research is needed to address long-term foal outcomes, no differences were seen in advanced imaging, biomechanical testing or gene expression by 30 days of age, suggesting that enrofloxacin may be a safe and useful antibiotic for select bacterial infections in pregnant mares.

Administration of enrofloxacin during late pregnancy failed to induce lesions in the resulting newborn foals

BACKGROUND

A recent study demonstrated that enrofloxacin and ciprofloxacin cross the equine placenta without causing gross cartilage or tendon lesions in the 9-month fetus; however, long-term effects of in utero fluoroquinolone exposure remain unknown.

OBJECTIVES

To assess effects of fetal exposure to enrofloxacin on the resulting foal's cartilage and tendon strength.

STUDY DESIGN AND METHODS

Healthy mares at 280 days' gestation were allocated into four groups: untreated (n = 5), therapeutic treatment (7.5 mg/kg enrofloxacin, PO × 14 days, n = 6), supratherapeutic treatment (15 mg/kg, PO × 14 days, n = 6) and no mare treatment with treatment of the foals post-partum (n = 2). Mares were allowed to carry pregnancy to term, and foals were maintained on pasture for 5 weeks. After that foals were euthanized, and their articular cartilage and extensor and flexor tendons were examined macroscopically and histologically for lesions. Tendon strength was tested by loading until failure.

RESULTS

Administration of enrofloxacin at recommended doses in late gestation did not result in cartilaginous lesions or clinical lameness in any foal by 5 weeks old. Tensile strength was greater in hind tendons than front tendons, but no difference was found between foals born from treated and control mares. Expectedly, osteochondral changes were present both in foals born from enrofloxacin-treated mares and in negative control foals with no apparent association with fluoroquinolone treatment during pregnancy.

MAIN LIMITATIONS

Only one time point in gestation was evaluated, and mares treated in the study were healthy at time of treatment. Additionally, it is possible that the assessments performed herein were not sensitive enough to detect subtle or functional changes in the articular cartilage. Further studies are needed to determine if enrofloxacin administration during late pregnancy potentiates osteochondral alterations in the first year of life.

CONCLUSIONS

While this study did not assess other stages of gestation or long-term foal outcomes, short-term administration of enrofloxacin to late gestation mares did not result in macroscopic or microscopic lesions in the resulting foals by 5 weeks of age.

Tendon Injury and Fluoroquinolone Use: A Systematic Review

BACKGROUND

Fluoroquinolone antibiotics are commonly used to treat infections and are prescribed by general practitioners, medical specialists and surgeons. Tendon injury has been associated with the use of these medications but the risk associated with newer fluoroquinolones has not been established.

OBJECTIVES

The aim of this systematic review was to evaluate the evidence from observational studies to determine the strength of the association between fluoroquinolone use and tendinopathy, and to identify risk factors for this complication.

METHODS

We searched MEDLINE, EMBASE and the Cochrane Collaboration from inception through May 2013 to identify observational studies focused on tendon injury and fluoroquinolones. Studies with original data were selected for inclusion following the PRISMA guidelines. Of the 560 abstracts screened, 16 relevant studies were independently rated by three authors (WW, AS, DC) using the Newcastle-Ottawa Quality Assessment Scale, and assigned a quality score out of 9. High-quality studies (i.e. scored 4.5 or higher) are summarized in detail in this article. Data were independently extracted by two authors (WW, AS).

RESULTS

Overall, 16 studies were included in our study. Eight were deemed to be of high quality and five specifically evaluated Achilles tendon rupture. In addition, three studies examined Achilles tendinitis, and three included tendon disorders (including any tendon rupture) as an outcome. Results from these studies suggest that individuals exposed to fluoroquinolones are at increased risk for Achilles tendon rupture, particularly within the first month following exposure to the drug (odds ratios ranged from 1.1 to 7.1). One study showed an increased risk of tendon rupture in those over 60 years of age. Five studies stated that individuals taking fluoroquinolones and oral corticosteroids are at increased risk for tendon injury compared with those taking fluoroquinolones alone. Four studies examined the differential effect of a limited number of fluoroquinolones. Ofloxacin had the highest risk of tendon injury in three of the studies.

LIMITATIONS

Included studies are observational in nature and rely on self-report, which may lead to misclassification or underestimation of tendon injury.

CONCLUSIONS

Observational studies showed an increased risk of tendon injury, including tendon rupture and tendinitis, with exposure to fluoroquinolone antibiotic therapy. Although this complication appears to be rare, concomitant corticosteroids increase the risk for tendon injury, which varies depending on the fluoroquinolone used.

Adult native knee extensor mechanism ruptures

Extensor mechanism rupture is a serious event requiring prompt diagnosis and treatment. Patella fractures are reportedly six times more frequent than soft tissue injuries such as quadriceps or patella tendon ruptures. Classically quadriceps and patella tendon ruptures are seen more in males, with those over 40 predominantly suffering from quadriceps tendon ruptures, often associated with an underlying condition, whereas patella tendon ruptures are mostly associated with sport injuries and are commonly seen in the under 40s. Almost all types of extensor mechanism ruptures benefit from early management which typically involves surgery. Diagnosis can be deemed easy to make by demonstrating inability to actively extend the knee, this however can be easily overlooked and missed in a busy emergency department leading to a late diagnosis and necessitating more complex surgery. Earlier surgical intervention and rehabilitation tend to produce improved outcomes.

Pitfalls in Sinus Surgery: An Overview of Complications

There is a potential for significant complications from the medical and surgical treatment of rhinosinusitis because of the intimate relationship between the paranasal sinuses and surrounding vital structures. Familiarity with the complex anatomic relationships between the skull base and other critical structures and knowledge of pharmacologic properties of commonly used medical therapies are essential for preventing serious and harmful seqsuelae. The authors hope that this review represents a valuable addition to the otolaryngologist-in-training's therapeutic armamentarium, and also serves as a reminder of the potential pitfalls for the experienced sinus surgeon.

Medicolegal Implications of Common Rhinologic Medications

As otolaryngologists, we prescribe many medications to our patients. The objective of this article is to review the potential side effects and medicolegal risks of the common medications used to treat chronic rhinosinusitis. The authors evaluate some of the common side effects as well as the published literature on the lawsuits associated with those medications. Finally, the authors review the informed consent discussion and opportunities to improve patient care and decrease the risk of litigation.

Oral fluoroquinolones and risk of glaucoma

OBJECTIVE

To evaluate the risk of developing glaucoma in patients taking systemic fluoroquinolones.

METHODS

A case-control study was carried out among a cohort of subjects who had visited an ophthalmologist in the Province of British Columbia, Canada from 2000 to 2007. Cases were identified as those newly diagnosed with glaucoma (ICD-9 360). For each case, 5 controls were selected and matched to the cases by age and calendar time. Crude and adjusted rate ratios (RRs) for current, recent, past, and distant use of fluoroquinolones were calculated.

RESULTS

From the cohort of 989,591 subjects, 178,264 subjects were diagnosed with glaucoma and 891,320 were corresponding controls. The 2 groups had same average age of 65 and comparable systemic comorbidities including hypertension, coronary artery disease, and diabetes. There was no statistically significant association between the use of systemic fluoroquinolones and the development of glaucoma for current use [RR=1.01 (95% confidence interval (CI), 0.95-1.07)], recent use [RR=1.00 (95% CI, 0.92-1.08)], or past use [RR=0.94 (95% CI, 0.90-1.00)]. Distant use of systemic fluoroquinolones had a small statistically significant increased risk of developing glaucoma [RR=1.12 (95% CI, 1.09-1.14)].

CONCLUSIONS

There was no detected increased association of the development of glaucoma with current, recent, or past use of systemic fluoroquinolone but a minimal statistically significant increased risk was associated with distant use. Future studies should further examine a potential delayed response with fluoroquinolones and glaucoma.

Rupture Following Biceps-to-Triceps Tendon Transfer in Adolescents and Young Adults With Spinal Cord Injury:: An Analysis of Potential Causes

BACKGROUND

Tendon transfer surgery can restore elbow extension in approximately 70% of persons with tetraplegia and often results in antigravity elbow extension strength. However, we have noted an almost 15% rupture/attenuation rate.

OBJECTIVE

This investigation was conducted to analyze potential causes in adolescents/young adults with spinal cord injury (SCI) who experienced tendon rupture or attenuation after biceps-to-triceps transfer.

METHODS

Medical charts of young adults with SCI who underwent biceps-to-triceps transfer and experienced tendon rupture or attenuation were reviewed. Data collected by retrospective chart review included general demographics, surgical procedure(s), use and duration of antibiotic treatment, time from tendon transfer surgery to rupture/attenuation, and method of diagnosis.

RESULTS

Twelve subjects with tetraplegia (mean age, 19 years) who underwent biceps-to-triceps reconstruction with subsequent tendon rupture or attenuation were evaluated. Mean age at time of tendon transfer was 18 years (range, 14-21 years). A fluoroquinolone was prescribed for 42% (n=5) of subjects. Tendon rupture was noted in 67% (n=8), and attenuation was noted in 33% (n=4). Average length of time from surgery to tendon rupture/attenuation was 5.7 months (range, 3-10 months).

CONCLUSION

Potential contributing causes of tendon rupture/attenuation after transfer include surgical technique, rehabilitation, co-contraction of the transfer, poor patient compliance, and medications. In this cohort, 5 subjects were prescribed fluoroquinolones that have a US Food and Drug Administration black box concerning tendon ruptures. Currently, all candidates for upper extremity tendon transfer reconstruction are counseled on the effects of fluoroquinolones and the potential risk for tendon rupture.

Acute and old ruptures of the extensor apparatus of the knee in adults (excluding knee replacement)

Rupture of the extensor apparatus of the knee in adults is infrequent and dominated by patellar fracture, which in our experience is six times as frequent as quadriceps or patellar tendon tear. Patellar fracture poses few diagnostic problems and treatment is now well codified. Tension-band osteosynthesis is generally used, involving two longitudinal K-wires and wire in a figure-of-eight pattern looped over the anterior patella; sometimes, for more complex fractures, cerclage wiring is added to the tension band. Non-union is rare and generally well tolerated. Quadriceps tendon tear mainly affects patients over 40 years of age, in a context of systemic disease. Diagnosis is easily suggested by inability to actively extend the knee, but is unfortunately still often overlooked in emergency. In most cases, early surgical management is needed to reinsert the tendon at the proximal pole of the patella by bone suture. For chronic lesions, it is often necessary to lengthen the quadriceps tendon by V-Y plasty or the Codivilla technique. Patellar tendon tear, on the other hand, typically occurs in patients under 40 years of age, often involved in sports. Diagnosis is again clinically straightforward, but again may be missed in emergency, especially in case of incomplete tear. Surgery is mandatory in all cases. The procedure depends on the type of lesion: either end-to-end suture or transosseous reinsertion. In most cases repair is protected by tendon augmentation. Old lesions often require tendon graft or a tendon-bone-tendon-bone graft taken from the opposite side.

Impact of age, sex, obesity, and steroid use on quinolone-associated tendon disorders

BACKGROUND

Quinolone antibiotics are associated with increased risk of tendinopathy. Identifying at-risk individuals has important clinical implications. We examined whether age, sex, glucocorticoid use, obesity, diabetes, and renal failure/dialysis predispose individuals to the adverse effects of quinolones.

METHODS

Among 6.4 million patients in The Health Improvement Network (THIN) database, 28,907 cases of Achilles tendonitis and 7685 cases of tendon rupture were identified in a case-crossover study. For each participant, we ascertained whether there was a prescription of a quinolone and comparison antibiotic within 30 days before the diagnosis of tendon disorder (case period) and a prescription of the same medications within 30 days 1 year before disease diagnosis (control period).

RESULTS

Use of quinolones was strongly associated with an increased risk of Achilles tendonitis (odds ratio [OR], 4.3; 95% confidence interval [CI], 3.2-5.7) and tendon rupture (OR, 2.0; 95% CI, 1.2-3.3). No association was found between the use of other antibiotics and either outcome. The association with Achilles tendonitis was stronger among participants who were aged more than 60 years (OR, 8.3 vs 1.6), who were nonobese (OR, 7.7 vs 2.4), and who used oral glucocorticoids (OR, 9.1 vs 3.2). The association was nonsignificantly stronger in women (OR, 5.0 vs 3.6), diabetic persons (OR, 7.0 vs 4.1), and those in renal failure or receiving dialysis (OR, 20.0 vs 3.9). The effect for tendon rupture was stronger in women, with borderline significance in glucocorticoid users and nonobese persons.

CONCLUSION

Quinolone-associated tendinopathy is more pronounced among elderly persons, nonobese persons, and individuals with concurrent use of glucocorticoids.

Detection of fluoroquinolone-induced tendon disorders using a hospital database in Japan

PURPOSE

Tendinitis and tendon rupture are well-known side effects of fluoroquinolones (FQs) in Western countries. In Japan, some case reports have been reported; however, the incidence of FQ-induced tendon disorders has not been investigated. The aims of this study were to measure the occurrence of tendon disorders associated with FQs in Japanese patients and to compare the observed risk with that of previous reports. Moreover, the observed risk in FQ-prescribed patients was compared with that in cephalosporin-prescribed patients.

METHODS

The Hamamatsu University Hospital database was examined to determine the risk of tendon disorders that occurred in all inpatients and outpatients between the first day of prescription of an oral FQ or cephalosporins to the calculated end date plus 30 days. The risk of tendon disorders, the risk ratio, and their 95% confidence intervals (CIs) were evaluated.

RESULTS

From April 1996 to December 2009, FQs were prescribed to 17 147 patients, 14 of whom had tendon disorders (risk: 0.082%, 95%CI: 0.049-0.137). The risk of a tendon disorder in FQ-prescribed patients was significantly higher than that in cephalosporin-prescribed patients (five tendon disorders in 38 517 patients, risk: 0.013%, 95%CI: 0.006-0.030, and p < 0.001). The risk ratio of a tendon disorder in FQ-prescribed patients in relation to cephalosporin-prescribed patients was 6.29 (95%CI: 2.27-17.46). A large discrepancy in the risk of tendon disorders was not observed between our findings and previous reports.

CONCLUSION

A hospital database search revealed that the risk of tendon disorders in Japanese patients administered with FQs was higher than in those administered with cephalosporins.

Musculoskeletal complications of fluoroquinolones: guidelines and precautions for usage in the athletic population

Fluoroquinolone antibiotics are associated with a wide spectrum of musculoskeletal complications that involve not only tendon but also cartilage, bone, and muscle. Insights into the pathoetiology of fluoroquinolone toxicity on musculoskeletal tissues have been evolving over recent years. Although the pathoetiology is certainly multifactorial, alterations in cell signaling proteins and direct toxic effects on musculoskeletal tissues have been strongly implicated. Increasing age and concomitant systemic corticosteroid use appear to significantly increase the risk of adverse events. The purpose of this article is to review the musculoskeletal complications associated with use of fluoroquinolone antibiotics by adults; identify risk factors associated with fluoroquinolone toxicity; explore the possible pathoetiology of fluoroquinolone toxicity on tendon, cartilage, bone, and muscle; and offer recommendations regarding evaluation and treatment of fluoroquinolone-associated musculoskeletal complications. In addition, this review will provide recommendations regarding fluoroquinolone use in athletes and return to play after fluoroquinolone exposure.

Non-crystalline and crystalline rheumatic disorders in chronic kidney disease

Rheumatic syndromes are cause for morbidity in patients with end-stage renal disease. Recent advances in understanding the role of tissue remodeling have provided insight into the pathogenic mechanisms responsible for some of these manifestations. Here, we survey recent and clinically relevant advances in translational research that impact our understanding of rheumatic syndromes seen in patients with significant renal disease. The management of acute and chronic crystalline arthropathies in chronic kidney disease and hemodialysis patients is discussed.

Pathogenesis of tendon rupture secondary to fluoroquinolone therapy

Tendon rupture related to trauma and corticosteroid injection, in and about tendon insertion sites, is well documented in the literature. Rupture of tendon after fluoroquinolone therapy has been identified in the recent past. Both short- and long-term courses of antibiotic treatment with fluoroquinolone may precipitate alteration in tendon matrix leading to tendinopathy with subsequent rupture. The pathogenesis of tendon rupture secondary to fluoroquinolone therapy is presented.