FIXATION METHODS IN LATARJET: BIOMECHANICAL COMPARISON OF SCREW TYPES AND PLATE FIXATION.

Objective: Latarjet procedure is often preferred in recurrent shoulder dislocations accompanied by glenoid bone loss. It is observed that the superiority of bone graft fixation methods is still controversial. The aim of this study is to biomechanically compare the bone graft fixation methods in the Latarjet procedure. Methods: 15 third-generation scapula bone models were divided into 3 groups. Graft was fixated in the first group with fully-threaded cortical screws of 3.5mm diameter, in the second group two 16 mm partially-threaded cannulated screws of 4.5mm diameter, and in the third group via a mini plate and screw. The hemispherical humeral head was placed on the tip of the cyclic charge device, and thus, the charge applied to the coracoid graft was homogeneous. Results: No statistically significant difference was found between paired comparisons (p>0.05). The forces in 5 mm displacement in total vary between 502-857N. Total stiffness measurements ranged between 105 and 625; the mean value was 258.13±53.54 with no statistically significant difference by groups (p = 0.958). Conclusion: This biomechanical study showed that there is no difference between three coracoid fixation options in terms of fixation strength. Unlike previous assumptions, plate fixation is not biomechanically superior to screw fixation. Surgeons should consider their personal preferences and experience in choosing fixation methods.

Objetivo: O procedimento Latarjet é normalmente preferencial em deslocamentos recorrentes do ombro acompanhados por perda óssea da glenóide. Observa-se que a superioridade dos métodos de fixação dos enxertos ósseos ainda é controversa. O objetivo deste estudo é comparar biomecanicamente os métodos de fixação de enxerto ósseo no procedimento Latarjet. Métodos: 15 modelos de escápulas de terceira geração foram divididos em 3 grupos. O enxerto foi fixado no primeiro grupo com parafusos corticais totalmente rosqueados com 3,5 mm de diâmetro, no segundo grupo com dois parafusos canulados parcialmente rosqueados de 16 mm de diâmetro de 4,5 mm e no terceiro grupo através de miniplaca e parafuso. A cabeça hemisférica umeral foi colocada na ponta do dispositivo de carga cíclica e, desta forma, a carga aplicada ao enxerto coracoide foi homogênea. Resultados: Nenhuma diferença estatisticamente significativa foi encontrada entre as comparações pareadas (p>0,05). As forças em 5 mm de deslocamento no total variam entre 502-857N. As medidas de rigidez total variaram entre 105 e 625 e o valor médio foi 258,13±53,54, sem diferença estatisticamente significativa por grupos (p = 0,958). Conclusão: Este estudo biomecânico mostrou que não há diferença entre três opções de fixação de coracoides em termos de resistência à fixação. Ao contrário de suposições anteriores, a fixação de placas não é biomecanicamente superior à fixação de parafusos. Os cirurgiões devem considerar suas preferências pessoais e sua experiência na escolha de métodos de fixação.

Fluid preloading before beach chair positioning for arthroscopic shoulder procedures: a randomized controlled trial

Abstract Background and objectives The Beach Chair Position (BCP) has many advantages such as less neurovascular injury and better intra-articular visualization, but it has also negative consequences, including hemodynamic instability. Although maintaining normal Mean Arterial Pressure (MAP) is important, fluid management is also a crucial concept for hemodynamic stability. The main objective of this study is whether preloading before positioning would be effective for less hemodynamic instability. Methods This randomized, controlled study was conducted in a single center in the Istanbul University, Istanbul Faculty of Medicine. Forty-nine patients undergoing elective arthroscopic surgery in the BCP were recruited. In the study group, crystalloid fluid at 10 mL.kg-1 of ideal body weight was administered intravenously 30 min before the BCP for preloading. The primary outcome measures were differences of hemodynamic variables as MAP, Stroke Volume (SV), Heart Rate (HR), and Cardiac Output (CO). The secondary outcome measures were Postoperative Nausea and Vomiting (PONV) rates in postoperative first day, surgical satisfaction scale, total ephedrine dose used during surgery, and total amount of fluid. Results The MAP, CO, and SV measurements of the study group were higher than those of the control group in the 5th minute after the BCP (respectively, p= 0.001, p= 0.016, p= 0.01). The total amount of crystalloid and surgical satisfaction scales were higher in the study group (respectively, p= 0.016, p= 0.001). Total amount of colloid and ephedrine dose used in the intraoperative period, and PONV rates were lower in the study group (p= 0.003, p= 0.018, p= 0.019, respectively). Conclusion Consequently, preloading can be favorable approach to preserve hemodynamic stability.

Fluid preloading before beach chair positioning for arthroscopic shoulder procedures: a randomized controlled trial.

BACKGROUND AND OBJECTIVES: The Beach Chair Position (BCP) has many advantages such as less neurovascular injury and better intra-articular visualization, but it has also negative consequences, including hemodynamic instability. Although maintaining normal Mean Arterial Pressure (MAP) is important, fluid management is also a crucial concept for hemodynamic stability. The main objective of this study is whether preloading before positioning would be effective for less hemodynamic instability. METHODS: This randomized, controlled study was conducted in a single center in the Istanbul University, Istanbul Faculty of Medicine. Forty-nine patients undergoing elective arthroscopic surgery in the BCP were recruited. In the study group, crystalloid fluid at 10...mL.kg-1 of ideal body weight was administered intravenously 30...min before the BCP for preloading. The primary outcome measures were differences of hemodynamic variables as MAP, Stroke Volume (SV), Heart Rate (HR), and Cardiac Output (CO). The secondary outcome measures were Postoperative Nausea and Vomiting (PONV) rates in postoperative first day, surgical satisfaction scale, total ephedrine dose used during surgery, and total amount of fluid. RESULTS: The MAP, CO, and SV measurements of the study group were higher than those of the control group in the 5th minute after the BCP (respectively, p...=...0.001, p...=...0.016, p...=...0.01). The total amount of crystalloid and surgical satisfaction scales were higher in the study group (respectively, p...=...0.016, p...=...0.001). Total amount of colloid and ephedrine dose used in the intraoperative period, and PONV rates were lower in the study group (p...=...0.003, p...=...0.018, p...=...0.019, respectively). CONCLUSION: Consequently, preloading can be favorable approach to preserve hemodynamic stability.