Background:The validation of widely used scales facilitates the comparison across international patient samples.Objective:The objective was to translate, culturally adapt and validate the Simple Shoulder Test into Argentinian Spanish.Methods:The Simple Shoulder Test was translated from English into Argentinian Spanish by two independent translators, translated back into English and evaluated for accuracy by an expert committee to correct the possible discrepancies. It was then administered to 50 patients with different shoulder conditions.Psycometric properties were analyzed including internal consistency, measured with Cronbach´s Alpha, test-retest reliability at 15 days with the interclass correlation coefficient.Results:The internal consistency, validation, was an Alpha of 0,808, evaluated as good. The test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.835, evaluated as excellent.Conclusion:The Simple Shoulder Test translation and it´s cultural adaptation to Argentinian-Spanish demonstrated adequate internal reliability and validity, ultimately allowing for its use in the comparison with international patient samples.

We describe the functional capability of a cross-linked hydrogel composed of sulfated glycosaminoglycans and a cationic cellulose by conducting trials on experimental animal models using intra-articular implants to treat an articular disease called osteoarthritis. Forty-eight mature New Zealand white rabbits were divided into three experimental groups: A, B, and C. Group A and B underwent unilateral anterior cruciate ligament transection (ACLT) of the right knee. Subsequently, both knees of group A were treated with the injectable formulation under study. Meanwhile, group B was treated with sterile PBS (placebo). The animals of group C were surgically operated in both knees: Commercial hyaluronic acid (HA) was implanted in the left knee, and the formulation under study was implanted in the right knee. After implantation, all specimens underwent several evaluations at 3, 6, and 12 months postoperatively. At 6 months, no significant differences were detected between the right and left knees of the different groups. However, significant differences were observed between both knees at 12 months in group C, with less cartilage damage in the right knees implanted with our hydrogel. Therefore, in vivo studies have demonstrated hydrogel safety, superior permanence, and less cartilage damage for long-term follow up 12 months after implantation for the formulation under study compared with commercial HA.

Introduction:The most recent advances in ACL reconstruction try to reproduce the anatomic femoral and tibial footprints as close as possible. Creating independent tunnels would allow an optimal of the entry point and the femoral tunnel obliquity, and together with an adequate reamer diameter they wouldreproduce with greater certainty the anatomy. Objective: To compare the radiographic parameters of the femoral and tibial tunnel positions in two groups of patients, one operated with a transtibial and other with transportal anatomic techniques. Conclusion:It is possible to create tibial and femoral tunnel in optimal positions but not equal between both groups. Creating independent tunnels allow a more anterior and vertical tibial tunnel allowing a better coverage of the tibial footprint. A transportal femoral tunnel would allow a better inclination angle and a lesser trans-osseous distance, technical details that would allow a better coverage of the femoral footprint.

Objective:Determine the normal value of shoulder muscle strengh, in an adult population divided in six groups between 20 to 86 years, without known shoulder pathology.Materials and Methods:523 individuals, 1046 shoulders, had their muscle strengh evaluated in two different positions, in 90 abduction and 90º fowarf flexion in the scapular plane. Three measurements were performed and the aveage one was recorded. Patiens with known shoulder pathology, reumathoid diseases, cancer were excluded. The patients were divided in six groups according to age, from 20 to 29 (68 patients), 30 to 39 (92 patients), 40 to 49 (109 patients), 50 to 59 (103 patients), 60 to 69 (91 patients) and 70 to 90 (60 patients). The strengh eas measured in pounds.Results:Average mucle strengh was 17,64 at the scapular plane and 16,82 lb at 90ª (p<0,0001)For the right shoulder, the average muscle strengh of the second decade group was 22 lb at scapular plane and 20,73 at 90º. The third decade was 19,93 and 18,50 respectively. The fouth decade values were 20,45 and 19,58, on the fifth decade 17,83 and 17,07. On the sixth decade was 15,57 and 15,23 and for the seventh decade was 11,40 and 11 lb respectively. The values for the left shoulder were for the second decade 21,53 om the scapular plane and 20,53 at 90º. On the third decade were 19,33 and 18,17, on the fourth decade 19,62 and 18,95, on the fifth decade were 16,8 and 16,2 , on the sixth decade 15,57 and 15,23. And for the final group 11,4 and 11 lb. Significant differences were seen between both shoulders ,sex (p<0,0001), position of the arm at time of measure (p0,0001), dominace (p0,001)Conclusion:The objective measurement of the muscle strengh of the shoulder varies significantly with age, sex and position of the arm at time of measure, putting in dout the validity of the contralateral shoulder as a value to compare against.

Background: The re-tear rate after surgical repair of chronic rotator cuff tears remains relatively high, however, little is known about the tendon to bone healing mechanism. More recently, bone marrow aspirate concentrate (BMAC) increases attention as a regenerative therapy for musculoskeletal disorder. The purpose of this study was (1) to create a chronic rotator cuff rabbit model, (2) to evaluate the influence of BMAC on tendon to bone healing in the chronic rotator cuff tear rabbit model. Material and methods: (1) To make a chronic rotator cuff model, 40 adult New Zealand white rabbits, aged 4 to 5 months, with a mean bodyweight of 2.9 kg were enrolled, a chronic tear was created by the supraspinatus tendon transection at the insertion site to the greater tuberosity and wrapping the torn tendon with a 10 mmelong silicone Penrose to inhibit adhesion to the surrounding soft tissue, then it was left alone for 6 weeks. (2) The rabbit model were randomly divided into 5 groups (8 rabbits per group) as follows: Control group (C), Repair + Saline (RS), Repair + PRP (RP), Repair + BMAC (RB) and Repair + PRP + BMAC (RPB). The torn tendon was repaired in an open transosseous manner. BMAC was prepared and administered onto the repair site according to the protocol, 6 weeks after repair the shoulder samples were harvested for the histological and biomechanical test. (3) In vitro study, BMAC was processed to analyze the growth factor level of PDGF-AB, IGF, TGF-ß1 and VEGF. Result: (1) The chronic rotator cuff model was confirmed by the development of fatty infiltration within the muscle after detachment 6 weeks. (2) The mechanical evaluation showed that RB group had a significantly higher stiffness and Young's module compared with the RS group (P ¼ 0 .002, P ¼ 0 .002, respectively). The ultimate load-to-failure was significantly higher in the RPB group compared with the RS and RP groups (P ¼ 0 .001, P ¼ 0 .03, respectively). The histological evaluation revealed that the BMAC treated groups (RB and RBP) showed better collagen fiber continuity and more regularly arranged collagen fibers than the group R and group RP. (3) The growth factor IGF, TGF-ß1 and VEGF was significantly higher in BMAC compared with PRP (P <0 .01). Conclusion: This study showed that BMAC release the greatest concentration of growth factors and play a central role to enhance the mechanical strength of tendon to bone junctions and to improve histological presentation after rotator cuff repair.