Effects of Static and Dynamic Hamstring Stretching on Anaerobic Exercise Performance

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Knotless PEEK and double-loaded biodegradable suture anchors ensure comparable clinical outcomes in the arthroscopic treatment of traumatic anterior shoulder instability: a prospective randomized study

Purpose: To compare the clinical outcome of arthroscopic capsulolabral repair for traumatic anterior shoulder instability with PEEK knotless and knotted biodegradable suture anchors. Methods: Arthroscopic stabilization was performed in 78 patients with recurrent traumatic anterior shoulder instability. They were divided into 2 groups of 39 patients each, according to suture anchors used: knotless PEEK anchors in group 1, and biodegradable anchors in group 2. Exclusion criteria were: instability without dislocation, posterior or multidirectional instability, glenoid bone loss > 20%, off-track lesions, concomitant rotator cuff tears and previous surgery. The primary outcome was the Disabilities of the Arm, Shoulder and Hand (DASH) self-administered questionnaire. Secondary outcomes were: Work-DASH, Sport-DASH, Rowe score, recurrent instability and subsequent surgery. The following independent variables were considered: age, gender, dominance, generalized ligamentous hyperlaxity, duration of symptoms, age at first dislocation, number of dislocations, type of work, type of sport, sports activity level, capsule-labral injury pattern, SLAP lesion and number of anchors. Differences between groups for numerical variables were analyzed by use of the Student’s t-test or Mann–Whitney U-test. Fisher’s exact test was used for analysis of categorical variables. Significance was set at p < 0.05. Results: Seven patients (9%) were lost at follow-up, 5 from group 1 and 2 from group 2. Follow-up ranged from 36 to 60 months (median: 44; IQR: 13). Comparison between groups did not show significant differences for each independent variable considered. No differences could be found either for DASH (n.s.) or Rowe (p = n.s.) scores between the two groups. Overall recurrence rate was 7%. Three re-dislocations were reported in group 1 and two in group 2 (n.s.). Only one patient in each group underwent re-operation. Conclusions: The study showed no significant differences in clinical outcomes after arthroscopic treatment of traumatic anterior shoulder instability using PEEK knotless or biodegradable knotted anchors at mid-term follow-up. Level of evidence: I

Electromechanical coupling of the Kv1.1 voltage-gated K+ channel is fine-tuned by the simplest amino acid residue in the S4-S5 linker

Investigating the Shaker-related K+ channel Kv1.1, the dysfunction of which is responsible for episodic ataxia 1 (EA1), at the functional and molecular level provides valuable understandings on normal channel dynamics, structural correlates underlying voltage-gating, and disease-causing mechanisms. Most studies focused on apparently functional amino acid residues composing voltage-gated K+ channels, neglecting the simplest ones. Glycine at position 311 of Kv1.1 is highly conserved both evolutionarily and within the Kv channel superfamily, is located in a region functionally relevant (the S4-S5 linker), and results in overt disease when mutated (p.G311D). By mutating the G311 residue to aspartate, we show here that the channel voltage-gating, activation, deactivation, inactivation, and window currents are markedly affected. In silico, modeling shows this glycine residue is strategically placed at one end of the linker helix which must be free to both bend and move past other portions of the protein during the channel’s opening and closing. This is befitting of a glycine residue as its small neutral side chain allows for movement unhindered by interaction with any other amino acid. Results presented reveal the crucial importance of a distinct glycine residue, within the S4-S5 linker, in the voltage-dependent electromechanical coupling that control channel gating

Case Report: Remarkable breakthrough: successful treatment of a rare intracranial mesenchymal, FET::CREB fusion-positive tumor treated with patient-tailored multimodal therapy

BackgroundIntracranial mesenchymal tumors are a rare type of neoplasm (0.3% of all soft tissue tumors) characterized by a fusion of a FET family gene (usually EWSR1, rarely FUS) to CREB family genes (CREB1, ATF1, and CREM) with a slow-growing and favorable prognosis. Mesenchymal tumors are most frequently localized in the subcutaneous tissue (typically in the limbs and hands) of young adults and have rarely been diagnosed in the central nervous system. Surgery is the gold standard treatment; adjuvant radiation therapy and chemotherapy with sarcoma-based regimens have been used in rare cases when complete surgical excision was not recommended. In terms of prognosis, these tumors show a tendency for local relapse. The longest patient outcomes reported in the literature are five years.Case descriptionThis case describes a 27-year-old woman with unconventional extracranial metastatic sites of myxoid intracranial mesenchymal tumor FET::CREB fusion-positive and high expression of PD-1 (40%) and PD-L1 (30%). Based on clinical, molecular, and histological characteristics, she underwent various local and systemic therapies, including surgery, proton beam therapy, the use of immune checkpoint inhibitors, and chemotherapy. These treatments led to a complete remission of the disease after eight years from tumor diagnosis.ConclusionsOur case sheds light on the importance of precision medicine and tailored therapy to explore new treatment opportunities for rare or unknown tumor entities

Surgical treatment of aseptic non-union in long bones: review of 193 cases

The surgical treatment of aseptic nonunion often represents a more challenging situation for the orthopaedic surgeon than treatment of the primary fracture. In fact, it may be necessary not only to "rivitalize" the nonunion area, but also to exchange the bone fixation devices and to place some refill material in the bone gap. Several surgical techniques and different kinds of bone gap refills have been reported in the literature for the treatment of long bone nonunion. We present the results of 193 cases of long bone nonunion that have been treated in a period of 11 years (1992–2003) by a mostly open approach to the nonunion site with or without autologous bone graft interposition. The site (27 humerus, 44 forearm, 48 femur, 74 tibia) and the type of nonunion (179 atrophic, 19 hypertrophic) were considered in the surgical planning as were the mechanic and biological problems. New osteosynthesis was performed in 139 cases: with plate and screws in 82 cases, with intramedullary nails in 31 cases, with external fixators in 15 cases and with other devices in 11 cases (e.g. interfragmentary screws, k-wires). Cancellous or corticocancellous bone graft, always autologous from the iliac crest or from the anterior tibial tuberosity, was used in 183 cases (94.8%). Healing of the nonunion was successful in 179 cases (92.7%) in a mean time of 5.8 months. 14 patients (7.2%), all atrophic nonunion, healed with further surgery in a mean time of 19.2 months. Best results were obtained by the use of the intramedullary nail (31 cases): 99% healed in 5.2 months for the lower limb and 100% healed in 7.4 months for the upper limb. Good results have been achieved by plate (82 cases): 89.5% healed in 4.5 months for the lower limb and 94.1% in 6 months for the upper one. The worst results were observed with external fixation (15 cases). However, this device was used in the most complex situations, when severe soft tissue sufference was present. In this group, the mean healing time was 7.1 months (69.2% of cases) in the lower limb and 8 months (50%) in the upper one. Bone graft alone (54 cases) led to healing in 34 of 35 cases (97%) in the lower limb in 6 months and in 17 of 19 cases (89.4%) in 6.4 months in the upper limb

Surgical treatment of fifth metacarpal neck fractures: antegrade intramedullary nailing versus transverse percutaneous pinning

BACKGROUND: To compare clinical and radiographic outcomes of antegrade intramedullary pinning (AIMN) and transverse percutaneous pinning (TPP) for the treatment of fifth metacarpal neck fractures.METHODS: A retrospective study was performed on patients surgically treated for a fifth metacarpal neck fracture be-tween 2009 and 2019. Sixty-three patients were included, divided into two groups according to the type of fixation: 33 pa-tients underwent surgery using antegrade intramedullary technique and 30 with transverse pinning. Clinical outcome was evaluated with DASH score, VAS, and active ROM. Volar angulation and shortening were determined on radiographs using DC-30 and SH-Stip methods, respectively. Healing time, return to work and complications were also assessed.RESULTS: Antegrade intramedullary pinning group showed significantly better outcome than transverse pinning in terms of DASH score, VAS score, return to work and fracture angulation. CONCLUSIONS: Antegrade intramedullary nailing provided better clinical and radiological outcomes than TPP. We found that AIMN technique resulted in better hand function, less residual pain and faster return to work. It also ensured a better fracture angulation correction

Surgical treatment of volar plate avulsion fractures of the proximal interphalangeal joint with suture anchors

BACKGROUND: To compare clinical and radiographic outcome of early and delayed surgical treatment of traumatic avulsion of the volar plate at the base of P2 of the fingers of the hand by bony fragment excision and reinsertion of the volar plate with suture anchor.METHODS: We retrospectively analyzed 26 cases of volar plate avulsion injuries of PIP joint surgically treated: 10 pa-tients underwent surgery immediately after trauma (early surgery group), and 16 beyond 30 days (delayed surgery group). Clinical outcome was evaluated using Quick-DASH Score, VAS, range of motion expressed as loss of motion (LOM) and strength measured with the tip-pinch test. Radiographic evaluation was performed to assess maintenance of reduction and complications such as signs of late osteoarthritis or intra-articular calcifications.RESULTS: LOM was significantly more severe in the delayed surgery group, both preoperatively and at follow-up. No significant differences were found between groups for Quick-DASH Score, VAS, stability, strength and late complica-tions and maintenance of reduction.CONCLUSIONS: Excision of the bony fragment from the base of P2 and use of a suture anchor for the bony reattach-ment of the volar plate demonstrated good clinical and radiographic results, with no risk of postoperative instability. Acute treatment reduced the risk of joint stiffness and provided better ROM of PIP joint than delayed surgery. Timing did not affect subjective outcome, strength, and occurrence of late sequelae

Electromechanical coupling of the Kv1.1 voltage-gated K(+)channel is fine-tuned by the simplest amino acid residue in the S4-S5 linker

Investigating theShaker-related K(+)channel Kv1.1, the dysfunction of which is responsible for episodic ataxia 1 (EA1), at the functional and molecular level provides valuable understandings on normal channel dynamics, structural correlates underlying voltage-gating, and disease-causing mechanisms. Most studies focused on apparently functional amino acid residues composing voltage-gated K(+)channels, neglecting the simplest ones. Glycine at position 311 of Kv1.1 is highly conserved both evolutionarily and within the Kv channel superfamily, is located in a region functionally relevant (the S4-S5 linker), and results in overt disease when mutated (p.G311D). By mutating the G311 residue to aspartate, we show here that the channel voltage-gating, activation, deactivation, inactivation, and window currents are markedly affected. In silico, modeling shows this glycine residue is strategically placed at one end of the linker helix which must be free to both bend and move past other portions of the protein during the channel's opening and closing. This is befitting of a glycine residue as its small neutral side chain allows for movement unhindered by interaction with any other amino acid. Results presented reveal the crucial importance of a distinct glycine residue, within the S4-S5 linker, in the voltage-dependent electromechanical coupling that control channel gating

Identification of a new de novo mutation underlying regressive episodic ataxia type I

Episodic ataxia type 1 (EA1), a Shaker-like K+channelopathy, is a consequence of genetic anomalies in the KCNA1 gene that lead to dysfunctions in the voltage-gated K+channel Kv1. 1. Generally, KCNA1 mutations are inherited in an autosomal dominant manner. Here we report the clinical phenotype of an EA1 patient characterized by ataxia attacks that decrease in frequency with age, and eventually leading to therapy discontinuation. A new de novo mutation (c.932G&gt;A) that changed a highly conserved glycine residue into an aspartate (p. G311D) was identified by using targeted next-generation sequencing. The conserved glycine is located in the S4-S5 linker, a crucial domain controlling Kv1.1 channel gating. In silico analyses predicted the mutation deleterious. Heterologous expression of the mutant (Kv1.1-G311D) channels resulted in remarkably decreased amplitudes of measured current, confirming the identified variant is pathogenic. Collectively, these findings corroborate the notion that EA1 also results from de novo variants and point out that regardless of the mutation-induced deleterious loss of Kv1.1 channel function the ataxia phenotype may improve spontaneously