Association of estrogen receptor ß polymorphisms with posterior tibial tendon dysfunction.

Posterior tibial tendon (PTT) dysfunction is three times more common in females, and some patients may have a predisposition without a clinically evident cause, suggesting that individual characteristics play an important role in tendinopathy. The present study investigated the association of rs4986938 (+ 1730G > A; AluI RFLP) and rs1256049 (- 1082G > A; RsaI RFLP) single nucleotide polymorphisms (SNPs) of estrogen receptor-beta (ER-ß) gene with PTT dysfunction. A total of 400 participants were recruited. The PTT dysfunction group: these patients underwent surgery, with PTT tendinopathy confirmed by histopathology and magnetic resonance image (MRI). The control group was composed of participants with no clinical or MRI evidence of PTT dysfunction. Each group was composed of 100 postmenopausal women, 50 premenopausal women, and 50 men. Genomic DNA was extracted from saliva samples, and genotypes were obtained by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Concerning the ER-ß SNP rs4986938, there were significant differences in the frequencies of alleles between test and control groups of all the cases, only postmenopausal women and only men (p < 0.0001, p = 0.0016 and p = 0.0001). Considering the PTT dysfunction group and comparing postmenopausal women versus premenopausal women adding men, the analysis showed significant differences in the allelic distribution (p = 0.0450): the allele A in postmenopausal women is a risk factor. The ER-ß SNP rs1256049 did not show differences in the frequencies of alleles and genotypes between groups. The ER-ß SNP rs4986938, but not ER -ß SNPs rs1256049, may contribute to PTT insufficiency in the Brazilian population, with additional risk in postmenopausal women. Addition, in men the genetic factor could be more determinant.

ERα PvuII and XbaI polymorphisms in postmenopausal women with posterior tibial tendon dysfunction: a case control study.

BACKGROUND: Posterior tibial tendon (PTT) insufficiency is considered as the main cause of adult acquired flat foot and is three times more frequent in females. High estrogen levels exert a positive effect on the overall collagen synthesis in tendons. We have previously demonstrated the association between some genetic single-nucleotide polymorphism (SNP) and tendinopathy. In the present study, we investigated the association of PvuII c454-397T>C (NCBI ID: rs2234693) and XbaI c454-351A>G (NCBI ID: rs9340799) SNPs in estrogen receptor alfa (ER-α) gene with PPT dysfunction. METHODS: A total of 92 female subjects with PTT dysfunction, with histopathological examination of the tendon and magnetic resonance image (MRI) evidence of tendinopathy, were compared to 92 asymptomatic females who presented an intact PPT at MRI for PvuII and XbaI SNPs in the ER-α gene. Genomic DNA was extracted from saliva and genotypes were obtained by polymerase chain reaction restriction fragment length polymorphism. RESULTS: The analysis of PvuII SNPs showed no significant differences in the frequency of alleles and genotypes between control and PTT dysfunction groups. The XbaI SNPs in the ER-α gene showed significant differences in the frequency of genotypes between control and test groups (p = 0.01; OR 95% 1.14 (0.55-2.33). CONCLUSIONS: The XbaI SNP in the ERα gene may contribute to tendinopathy, and the A/A genotype could be a risk factor for PTT tendinopathy in this population. The PvuII SNP studied was not associated with PTT tendinopathy.

MMP-8 polymorphism is genetic marker to tendinopathy primary posterior tibial tendon.

Posterior tibial tendon is particularly vulnerable and is responsible for much morbidity in sportspersons. Some patients have a predisposition without a clinically recognized cause, suggesting that individual characteristics, inclusive genetic inheritance, play an important role in tendinopathy. Matrix metalloproteinase (MMP)-8 is a proteinase capable of degrading a large amount of extracellular proteins, and influence degradation and remodeling of collagen. To determine whether the -799 polymorphism in the promoter of MMP-8 gene is associated with tendinopathy in posterior tibial tendon, 50 patients undergoing surgical procedures and anatomopathological diagnosis of degenerative lesions of the posterior tibial tendon and 100 control patients with posterior tibial tendon integrity and without signs of degeneration in magnetic resonance imaging were evaluated for the -799 MMP-8 polymorphism. There was a significant difference in the presence of the different alleles (P = 0.001) and genotype (P = 0.003) between the control group and the test group for the MMP-8 gene. The polymorphism at position -799 of the gene for MMP-8 is associated with tendinopathy primary posterior tibial tendon in the population studied. The results suggest that individuals with the T allele are at greater risk of developing tendinopathy.

Fracture of the talar neck associated with a compression fracture of the calcaneocuboid joint in a 5-year-old child: a case report.

OBJECTIVE: The objectives of this present case study are to report a rare combination of a displaced talar neck fracture with a compression fracture of the calcaneocuboid joint in a 5-year-old child and to describe its radiological features, surgical treatment and clinical outcome. A 5-year-old male boy was injured in a car accident in which his left foot underwent one of the tires. On arrival at the hospital, a displaced talar neck fracture associated both with a cuboid fracture and compression of the articular surface of the cuboid at the calcaneocuboid join was identified. Fractures were fixed surgically. Leg was protected with a below-knee plaster split immobilization and non-weight-bearing for 5 weeks. After that period, the patient initiated a rehabilitation protocol with active and passive motion exercises. DISCUSSION: Fractures and fracture dislocations at the mid-tarsal joint have an important impact on the global foot function because malunion can result in post-traumatic arthritis and three-dimensional deformities of the foot. If a cuboid compression fracture is not reduced properly, it can result in the shortening of the lateral column with the development of an abduction, pronation and flat foot deformity. A talar neck fracture, if unreduced, can result in medial column displacement and rotational dislocation of the talar head, leading to a subluxation in the talonavicular joint with severe restriction of foot function. With early surgical treatment and open reduction and internal fixation, our patient recovered from the accident without having symptoms of pain, avascular necrosis, postoperative foot deformities or neurovascular deficits. CONCLUSIONS: The combination of a displaced talar neck fracture with a compression fracture of the calcaneocuboid joint in children usually requires correct diagnoses and early treatment with anatomic reduction and internal fixation to prevent severe post-traumatic deformities. LEVEL OF EVIDENCE: V.

MMP-3 polymorphism: Genetic marker in pathological processes (Review).

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that are collectively capable of cleaving virtually all extracellular matrix (ECM) substrates and play an important role in diverse physiological and pathological processes. The activity of MMPs is controlled at multiple levels, and the transcriptional regulation of MMPs appears to represent a necessary step in its regulation. MMP-3 is a key member of the MMP family with broad substrate specificity, and is crucial to the connective tissue remodeling process. It is also involved in the turnover of the numerous ECM components. A common functional promoter polymorphism of MMP-3, 5A/6A, affects its activity and has been associated with various diseases. This polymorphism may be used as a genetic marker for certain pathologies to identify individual susceptibility. This review discusses various topics related to MMP-3 in pathological processes, with a focus on the 5A/6A polymorphism.