Stress shielding: short-term radiological results of the reverse shoulder arthroplasty with an anatomic proximal coated stem in proximal humeral fractures.

PURPOSE: This study aims to determine the stress shielding and other radiological outcomes of patients who underwent an uncemented reverse shoulder arthroplasty (RSA) with an anatomic proximal coated stem for complex proximal humeral fractures (PHF) with 3 or 4 parts at 2 years postoperatively. METHODS: 37 shoulders underwent an uncemented RSA for PHF from November 2015 to February 2019 and were followed up for 2 years. A radiographic assessment of stress shielding, filling ratio, stem stability (radiolucent lines/subsidence/alignment), tuberosity healing and notch was performed. RESULTS: The mean age at the time of surgery was 72 years (range, 61-85). Stress shielding was appreciated in 31 shoulders (83.8%). The most important characteristic of stress shielding is cortical resorption: Grade 3 resorption occurred in 3 shoulders (8.1%) and grade 4 in 23 (62.2%) as per the grading system defined by Inoue et al. (Inoue et al. in J Shoulder Elbow Surg 26:1984-1989, 2017). A high occurrence of bone resorption was observed in Gruen zones 2 (Lateral Stress shielding) and 7 (Medial Stress shielding). The mean distal filling ratio in patients without stress shielding was 78,48(SD 14,9), whereas in patients with stress shielding, it was slightly higher with a mean of 81,68% (SD 4,89). Tuberosity healing was found in 94.6% (35/37) of the shoulders. No patient had any radiolucent line. No notch was observed. CONCLUSION: At short-term follow-up, a high rate of tuberosity healing was achieved (94.6%) even though stress shielding was found in 83.8% (31/37) of the shoulders. Bone resorption was most frequently observed externally at zone 2 (Lateral stress shielding) and internally at zone 7 (Medial stress shielding). A higher filling ratio was associated with an increased occurrence of stress shielding. The uncemented anatomic humeral component did not result in early loosening. LEVEL OF EVIDENCE: IV; Case Series; Treatment study.

Reverse total shoulder arthroplasty with latissimus dorsi and teres major transfer: biomechanical and electromyographical outcomes.

PURPOSE: There is controversy regarding the optimal treatment for patients with rotator cuff arthropathy with external rotation deficit (CLEER group). This study analyzes the biomechanical and electromyographical outcomes of reverse total shoulder arthroplasty (RTSA) with latissimus dorsi and teres major transfer. The primary objective of this study is to compare the biomechanical and electromyographical outcomes between the treated and contralateral shoulder. Secondary objective is to define clinical and functional outcomes, and to report the radiological findings. Our hypothesis is that with this technique patients regain at least 50% of the strength in external rotation of the contralateral shoulder, and that the transferred muscles remain EMG active over time. MATERIALS AND METHODS: All patients who underwent RTSA with latissimus dorsi and teres major transfer in our hospital between 2007 and 2015 were included. From 16 eligible patients, 10 were finally reviewed. Biomechanical assessment of rotation strength was performed postoperatively in both shoulders, and fine needle EMG of latissimus dorsi and teres major muscles was recorded at the same time in both shoulders. Constant test and clinical evaluation (Lag sign and Hornblower test) were obtained preoperative and at final follow up. Radiological (X-ray, US) assessment was also obtained for both shoulders at final follow up. RESULTS: External rotation strength of the operated shoulder was higher than 50% the strength of the contralateral shoulder, and the differences were statistically significant (p < 0.05). No statistically differences were found regarding to internal rotation. The electromyographic assessment found no significant differences (p > 0.05) between the treated and contralateral shoulders. The mean Constant-Murley score significantly increased (30.9 points) after surgery (p < 0.01). Lag sign and Hornblower test were negative in all patients. CONCLUSIONS: Performing RTSA with latissimus dorsi and teres major transfer is an effective procedure improve function and to restore ER strength in patients in CLEER group. The EMG records shows that transposed latissimus dorsi and teres major adapt to their new function and remain functional over time, even in elderly patients.

Telemedicine approach for patient follow-up after total knee and reverse total shoulder arthroplasty: a pilot study.

PURPOSE: The study aimed to demonstrate the reduction in postoperative follow-up visit time for patients receiving total knee arthroplasty (TKA) or reverse total shoulder arthroplasty (RTSA) by implementing a novel asynchronous telemedicine system compared to face-to-face visits. The range of motion interobserver agreement and patient satisfaction were evaluated in the telemedicine group. METHODS: A randomized controlled trial was conducted with a total of 28 patients with a mean age of 71 years (range 13.3). Patients were distributed into two study groups, TKA (n = 14) and RTSA (n = 14), and each group was randomly allocated into a face-to-face or virtual follow-up visit group. For the virtual group, software was designed including patient-specific model items (X-ray, range of motion and functional scores) for each arthroplasty. Functional assessment was conducted using the International Knee Documentation Committee (IKDC) score for TKA and American Shoulder and Elbow score (ASES) and Simple Shoulder Test (SST) for RTSA. The range of motion interobserver concordance was conducted in the virtual follow-up groups via an intraclass correlation coefficient. Finally, a satisfaction survey was performed in the virtual follow-up groups. Mann-Whitney U test was used for statistical analysis. RESULTS: Mean time differences between face-to-face and virtual follow-ups were 502.5 s (95% CI 387.8-617.1; p < 0.002) in the RTSA group and 710 s (95% CI 597.91-822; p < 0. 002) in the TKA group. The range of motion interobserver concordance in the virtual group was 0.974 for TKA and 0.804 for RTSA. Finally, virtual follow-up satisfaction using the telematic method was 8.9 out of 10. CONCLUSION: The results of this study showed that a virtual follow-up using asynchronous telemedicine systems could reduce visit times, allow a correct articular range of motion evaluation and maintain satisfaction perception for patients. Asynchronous telemedicine could be an efficient method to conduct postoperative follow-up after knee and shoulder arthroplasty.

Estandarización de aspectos preanalíticos para el estudio de biomarcadores de la enfermedad de Alzheimer en el líquido cefalorraquídeo / Standardization of preanalytical factors to study biomarkers of Alzheimer's disease in cerebrospinal fluid

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[Role of biomarkers in the early diagnosis of Alzheimer's disease]. / Papel de los biomarcadores en el diagnóstico precoz de la enfermedad de Alzheimer.

Alheimer's disease is the most frequent cause of cognitive decline and behavioral abnormalities in adults. Diagnosis is currently made in the advanced phases. An an early diagnosis in the prodromal phase (or earlier if possible) is required for the prevention of this disease, its early management and the development of potential therapies that could alter its natural course. The syndromic concept of mild cognitive impairment (the presence of detectable and quantifiable deterioration in one of the cognitive domains but without affecting -or without substantially affecting- autonomic performance of instrumental function) and its variants has aided understanding of the predementia stages of Alheimer's disease, even though its etiology may involve multiple factors. The use of biomarkers such as determination of the proteins involved in the disease in cerebrospinal fluid (Aß42-amyloid, total and phosphorylated tau) and measurement of the hippocampus and entorhinal cortex with magnetic resonance imaging and positron emission tomography (both glucose and amyloid measurements), alone or combined, could allow early and etiologic diagnosis. Patients with Alzheimer's disease show reduced Aß42-amyloid levels and increased total and phosphorylated tau levels in cerebrospinal fluid.

Papel de los biomarcadores en el diagnóstico precoz de la enfermedad de Alzheimer / Role of biomarkers in the early diagnosis of Alzheimer’s disease

La enfermedad de Alzheimer (EA) es la causa más frecuente de deterioro cognitivo y conductual en adultos. Actualmente, el diagnóstico se realiza en las fases avanzadas de la enfermedad. La posible prevención de la enfermedad, su abordaje temprano y la aparición de posibles terapias que puedan variar la evolución natural de la EA hace preciso el diagnóstico precoz en fase prodrómica (o antes si es posible) de la enfermedad. El concepto sindrómico de deterioro cognitivo leve (existencia de un deterioro detectable y cuantificable en alguno de los dominios cognitivos pero que no afecta —o no lo hace sustancial— a la ejecución autónoma de funciones instrumentales) con sus variantes ayudó a la visualización más patente de fases predemenciales de la EA aunque su origen pueda ser plurietiológico. El uso de biomarcadores como la determinación de proteínas implicadas en la enfermedad en líquido cefalorraquídeo (LCR) —beta-amiloide 42, tau total y tau fosforilada—, las mediciones del hipocampo y el córtex entorrinal por resonancia magnética y la tomografía por emisión de positrones (tanto de glucosa como de amiloide), solos o en combinación, pueden hacer posible efectuar diagnósticos más tempranos y etiológicos. Los pacientes con EA presentan una concentración disminuida de beta-amiloide 42 y un incremento de los niveles de tau total y tau fosforilada en el LCR (AU)

Alheimer’s disease is the most frequent cause of cognitive decline and behavioral abnormalities in adults. Diagnosis is currently made in the advanced phases. An an early diagnosis in the prodromal phase (or earlier if possible) is required for the prevention of this disease, its early management and the development of potential therapies that could alter its natural course. The syndromic concept of mild cognitive impairment (the presence of detectable and quantifiable deterioration in one of the cognitive domains but without affecting —or without substantially affecting— autonomic performance of instrumental function) and its variants has aided understanding of the predementia stages of Alheimer’s disease, even though its etiology may involve multiple factors. The use of biomarkers such as determination of the proteins involved in the disease in cerebrospinal fluid (Aβ42-amyloid, total and phosphorylated tau) and measurement of the hippocampus and entorhinal cortex with magnetic resonance imaging and positron emission tomography (both glucose and amyloid measurements), alone or combined, could allow early and etiologic diagnosis. Patients with Alzheimer’s disease show reduced Aβ42-amyloid levels and increased total and phosphorylated tau levels in cerebrospinal fluid (AU)

Updated classification system for proximal humeral fractures.

Proximal humeral fractures can restrict daily activities and, therefore, deserve efficient diagnoses that minimize complications and sequels. For good diagnosis and treatment, patient characteristics, variability in the forms of the fractures presented, and the technical difficulties in achieving fair results with surgical treatment should all be taken into account. Current classification systems for these fractures are based on anatomical and pathological principles, and not on systematic image reading. These fractures can appear in many different forms, with many characteristics that must be identified. However, many current classification systems lack good reliability, both inter-observer and intra-observer for different image types. A new approach to image reading, following a well-designed set and sequence of variables to check, is needed. We previously reported such an image reading system. In the present study, we report a classification system based on this image reading system. Here we define 21 fracture characteristics and apply them along with classical Codman approaches to classify fractures. We base this novel classification system for classifying proximal humeral fractures on a review of scientific literature and improvements to our image reading protocol. Patient status, fracture characteristics and surgeon circumstances have been important issues in developing this system.

Proposed protocol for reading images of humeral head fractures.

UNLABELLED: Fractures of the proximal humerus can be treated effectively but require proper characterization. None of the existing classifications intended to facilitate characterization have been satisfactory. We studied proximal humerus fractures using radiographs alone and radiographs plus computed tomography scans to ascertain which imaging studies were most useful to characterize these fractures. We designed an assessment protocol consisting of 17 parameters divided in four groups: cephalodiaphyseal relationship (six parameters), cephalotuberosity relationship (six parameters), humeral head (two parameters), and fracture fragment description (three parameters). The computed tomography scans were assessed using 11 parameters (the same parameters used for assessing radiographs except for the six cephalodiaphyseal parameters). Four observers analyzed the parameters in 30 selected fractures with biplanar radiographic projections (30 patients) and computed tomography scans (22 patients) on two occasions. We found good interobserver reliability and intraobserver reliability with radiographs alone for the cephalodiaphyseal parameters. The best interobserver reliabilities with radiographs plus computed tomography scans were with the number of fragments, displacement of the lesser tuberosity, and extraarticular or articular fractures. Computed tomography allows better assessment of some parameters in characterizing proximal humeral fractures. The use of a structured protocol in reading images seems useful and allows better reliability than reported for other approaches. LEVEL OF EVIDENCE: Diagnostic study, Level III (study of nonconsecutive patients without consistently applied reference "gold" standard). See the Guidelines for Authors for a complete description of levels of evidence.

Utilidad de la memantina en la enfermedad de Alzheimer / Memantine´s utility in Alzheimer´s disease

La enfermedad de Alzheimer (EA) es la forma más frecuente de demencia en los países occidentales. Los beneficios que se observan con los tratamientos actualmente aprobados son fundamentalmente sintomáticos sin evidencia clara de neuroprotección. Los antagonistas del receptor del N-metil-D-aspartato (NMDA) presentan potencial terapéutico para el tratamiento de varias enfermedades del sistema nervioso central, incluyendo la neuroprotección de enfermedades neurodegenerativas crónicas y el tratamiento sintomático de otras enfermedades neurológicas. La memantina, un antagonista del NMDA, ha sido recientemente aprobada para el tratamiento de la EA avanzada. Por su mecanismo de acción la memantina se considera un fármaco neuroprotector, cuya utilidad se demostró en estudios preclínicos. Asimismo, la memantina es un tratamiento sintomático útil en la EA y la demencia vascular. En esta revisión se analizan ambos aspectos de la memantina, al igual que los mecanismos básicos implicados en la cognición y en la neurodegeneración glutamatérgica.

[Renal involvement in the human immunodeficiency virus infection]. / Alteración renal en la infección por el virus de la inmunodeficiencia humana.

BACKGROUND AND OBJECTIVE: Although renal pathologies are becoming an emergent problem in the population infected by the human immunodeficiency virus (HIV), there is very scarce information about the natural course of this problem. The objective of the present study is to describe renal lesions in an autopsy series of HIV-infected patients never treated with antiretroviral therapies. PATIENTS AND METHOD: Autopsy information has been retrospectively retrieved from 61 HIV-infected subjects (mean age, 36,9 [8,4] years; 58,6% drug abusers, 84% males) died in our hospital between 1984 and 1997. None of the patients received antiretroviral therapy. All autopsy and clinical reports were considered, as well as basic analytical parameters about renal function. Renal autopsy samples were specifically reviewed. RESULTS: At the time of the last admission, 9.8% of patients had renal insufficiency, who made up 44.3% of patients having renal insufficiency anytime. Infections were the main cause of death (76%). The majority of patients (93.4%) showed histopathological renal abnormalities, which were highly heterogeneous. Renal lesions were mainly located on the tubules (96.7%) and the interstitium (60.7%). Moreover, glomeruli were affected in 55.7% of patients. Most frequent histopathological diagnosis was acute tubular necrosis (16.4%) and septic nephritic abscesses (16.4%), followed by tubulointerstitial nephritis (9%). HIV-associated nephropathy was present in two patients (3.3%). There were no significant differences when considering the existent of renal failure. CONCLUSIONS: Renal histological abnormalities are frequent in the natural evolution of HIV infection. There is an important heterogeneity of lesions, mainly involving tubules, interstitium and mesangium. The cause of renal lesions is predominantly septic, according to the chief systemic process. It does not exist any relationship between renal analytical parameters and the presence of renal damage.

Reversible posterior leukoencephalopathy secondary to indinavir-induced hypertensive crisis: a case report.

Reversible posterior leukoencephalopathy syndrome (RPLS) is an uncommon entity related to multiple and different pathologies, the most common being hypertensive crisis. It is believed to be secondary to the breakdown on the blood-brain barrier. At the beginning, it is undistinguishable from other leukoencephalopathies. However, the disappearance of brain lesions after removal of the potential cause, establish the differential diagnosis with other leukoencephalopathies. We present the case of an HIV-infected patient with a RPLS related to a hypertensive crisis short after the initiation of indinavir-containing highly active antiretroviral therapy. Once blood pressure was controlled and indinavir replaced by nelfinavir, white matter lesions at magnetic resonance imaging disappeared. The clinical and radiologic evolution excludes other diagnosis as progressive multifocal leukoencephalopathy and points indinavir as a potential hypertension-inducing agent in HIV-infected predisposed subjects.