The effect of intra-articular levobupivacaine on shoulder cartilage at different doses - experimental study / O efeito de levobupivacaína intra-articular na cartilagem do ombro em doses diferentes-estudo experimental

Abstract Background and objectives: In this study it was aimed to examine the histological and morphometric effects on cartilage structure of intra-articular application of levobupivacaine to the shoulder joint. Methods: In twenty New Zealand adult male rabbits, 35 shoulders were used for the study and prepared in 5 groups of 7. These groups were defined as Groups L1, L2, L3 and L4 which were right shoulders administered with 0.25% and 0.5% levobupivacaine, Group C which were left shoulders as the control group and Groups S1 and S2 which were left shoulders administered with 0.9% saline. On the 2nd and 15th days the animals were killed, the glenohumeral joints were evaluated macroscopically then cartilage samples were taken. These samples were evaluated with Mankin score, and histomorphometrically by measuring the thickness of the cartilage between the superficial cartilage layer and the tidemark and the thickness of calcified cartilage between the tidemark and the subchondral bone. Results: Macroscopically, on the 15th day the joint fluid was seen to have reduced in all the groups. After microscopic evaluation, the highest Mankin score (mean: 3.14 ± 2.1/14) was in the L4 group (15th day 0.5% levobupivacaine) and was found to be statistically significant (p < 0.05). No statistically significant difference was determined between the other groups. Conclusions: Histologically, as the highest Mankin score was in the L4 group, this indicates that in a single intra-articular injection of levobupivacaine a low concentration should be selected. Level of evidence: Level 5, animal study.

Resumo Justificativa e objetivo: Neste estudo o objetivo foi examinar os efeitos histológicos e morfométricos sobre a estrutura da cartilagem da aplicação intra-articular de levobupivacaína em articulação do ombro. Métodos: Trinta e cinco ombros de 20 coelhos New Zealand, machos e adultos, foram usados para o estudo e divididos em cinco grupos de sete. Os grupos foram definidos como L1, L2, L3 e L4, consistiram em ombros direitos nos quais levobupivacaína a 0,25% e 0,5% foi administrada; o Grupo C, que consistiu em ombros esquerdos, foi o grupo controle; os grupos S1 e S2, que consistiram em ombros esquerdos, receberam solução salina a 0,9%. Os animais foram sacrificados no segundo e no 15º dia; as articulações glenoumerais foram avaliadas macroscopicamente e, em seguida, amostras de cartilagem foram coletadas. As amostras foram avaliadas com o escore de Mankin e histomorfometricamente. Mediu-se a espessura da cartilagem entre a camada superficial e a "linha de maré" (tidemark) e a espessura da cartilagem calcificada entre a tidemark e o osso subcondral. Resultados: Macroscopicamente, observou-se no 15º dia que o líquido articular havia reduzido em todos os grupos. Após a avaliação microscópica, o maior escore de Mankin (média: 3,14 ± 2,1/14) foi observado no grupo L4 (15º dia levobupivacaína a 0,5%), considerado estatisticamente significativo (p < 0,05). Nenhuma diferença estatisticamente significativa foi determinada entre os outros grupos. Conclusões: Histologicamente, como o maior escore de Mankin foi observado no Grupo L4, isso indica que em uma única injeção intra-articular de levobupivacaína uma concentração baixa deve ser selecionada. Nível de evidência: Nível 5, estudo em animais.

[The effect of intra-articular levobupivacaine on shoulder cartilage at different doses-experimental study]. / O efeito de levobupivacaína intra­articular na cartilagem do ombro em doses diferentes­estudo experimental.

BACKGROUND AND OBJECTIVES: In this study it was aimed to examine the histological and morphometric effects on cartilage structure of intra-articular application of levobupivacaine to the shoulder joint. METHODS: In twenty New Zealand adult male rabbits, 35 shoulders were used for the study and prepared in 5 groups of 7. These groups were defined as Groups L1, L2, L3 and L4 which were right shoulders administered with 0.25% and 0.5% levobupivacaine, Group C which were left shoulders as the control group and Groups S1 and S2 which were left shoulders administered with 0.9% saline. On the 2nd and 15th days the animals were killed, the glenohumeral joints were evaluated macroscopically then cartilage samples were taken. These samples were evaluated with Mankin score, and histomorphometrically by measuring the thickness of the cartilage between the superficial cartilage layer and the tidemark and the thickness of calcified cartilage between the tidemark and the subchondral bone. RESULTS: Macroscopically, on the 15th day the joint fluid was seen to have reduced in all the groups. After microscopic evaluation, the highest Mankin score (mean: 3.14±2.1/14) was in the L4 group (15th day 0.5% levobupivacaine) and was found to be statistically significant (p<0.05). No statistically significant difference was determined between the other groups. CONCLUSIONS: Histologically, as the highest Mankin score was in the L4 group, this indicates that in a single intra-articular injection of levobupivacaine a low concentration should be selected. LEVEL OF EVIDENCE: Level 5, animal study.

The effect of intra-articular levobupivacaine on shoulder cartilage at different doses-experimental study.

BACKGROUND AND OBJECTIVES: In this study it was aimed to examine the histological and morphometric effects on cartilage structure of intra-articular application of levobupivacaine to the shoulder joint. METHODS: In twenty New Zealand adult male rabbits, 35 shoulders were used for the study and prepared in 5 groups of 7. These groups were defined as Groups L1, L2, L3 and L4 which were right shoulders administered with 0.25% and 0.5% levobupivacaine, Group C which were left shoulders as the control group and Groups S1 and S2 which were left shoulders administered with 0.9% saline. On the 2nd and 15th days the animals were killed, the glenohumeral joints were evaluated macroscopically then cartilage samples were taken. These samples were evaluated with Mankin score, and histomorphometrically by measuring the thickness of the cartilage between the superficial cartilage layer and the tidemark and the thickness of calcified cartilage between the tidemark and the subchondral bone. RESULTS: Macroscopically, on the 15th day the joint fluid was seen to have reduced in all the groups. After microscopic evaluation, the highest Mankin score (mean: 3.14±2.1/14) was in the L4 group (15th day 0.5% levobupivacaine) and was found to be statistically significant (p<0.05). No statistically significant difference was determined between the other groups. CONCLUSIONS: Histologically, as the highest Mankin score was in the L4 group, this indicates that in a single intra-articular injection of levobupivacaine a low concentration should be selected. LEVEL OF EVIDENCE: Level 5, animal study.

Can we gain an advantage by combining distal median, radial and ulnar nerve blocks with supraclavicular block? A randomized controlled study.

PURPOSE: The aim of this study was to compare the combined ultrasound-guided supraclavicular brachial plexus block (SCB) and distal median, radial, and ulnar nerve blocks, with the supraclavicular block alone. METHOD: Sixty-two patients undergoing upper extremity surgery were randomized to supraclavicular only (Group S, n = 31) or supraclavicular + distal (Group SD, n = 31) group. Patients in Group S received 32 mL of 1.5 % lidocaine + epinephrine 5 µg/mL, while those in Group SD received 20 mL of 1.5 % lidocaine + epinephrine 5 µg/mL followed by distal median, radial, and ulnar nerve blocks using equal volumes of 2 % lidocaine + 0.5 % levobupivacaine (4 mL/nerve). Sensory and motor blocks of the ulnar, median, radial and musculocutaneous nerves were assessed every 5 min starting at the 10th minute. The imaging, needling and performance times were recorded. Also, the onset and anesthesia-related times, need for analgesic and first analgesic times, were noted. RESULTS: In Group SD, the anesthesia onset [15 (10-25) vs. 20 (15-30) min, p < 0.001] and anesthesia related times [16.6 (10.7-28.2) vs. 22 (15.9-33.7) min, p < 0.001] were significantly shorter than those of Group S. Additionally, the analgesic requirement was lower in Group SD (56.7 vs. 88.5 %, p = 0.009), while among the patients who required analgesic, the first analgesic time was longer in Group SD in comparison to Group S [625 (347-1764) vs. 315 (233-746) min p < 0.001]. CONCLUSIONS: The addition of distal median, radial, and ulnar nerve blocks to SCB shortens anesthesia-related time and anesthesia onset time when compared with a SCB alone.

Ultrasound anatomy of the brachial plexus nerves in the neurovascular bundle at the axilla in patients undergoing upper-extremity block anesthesia.

PURPOSE: Familiarity with the localization of the nerves in the neurovascular bundle that constitutes the axillary segment of the brachial plexus (BP) is important when applying ultrasound (US)-guided block anesthesia. Therefore in this study we aimed to delineate the anatomy of the median, radial, and ulnar nerves of the BP at the axilla with US and electrical stimulation. MATERIALS AND METHODS: The study included 60 patients who were scheduled to undergo upper-arm surgery with axillary block anesthesia. Prior to anesthesia, ulnar, radial, and median nerves were localized with US using a 12-h quadrant identification system that placed the axillary artery (AA) in the middle. The nerves were then functionally tested using a neurostimulator. RESULTS: The radial nerve was mainly located in the 4-6 o'clock arc (posterior and posteromedial to AA) in 50 (83 %) of patients. Ulnar nerve was mainly at the 12-3 o'clock arc (anteromedial to AA) in 51 (85 %) of patients. Ulnar nerve showed a second peak at 9-10 o'clock quadrant (anterolateral to AA) in 11 % (7) of patients. Median nerve location was most common in the 12 and 9 o'clock arc (anterior and anterolateral to AA) in 53 (88 %) of the patients. CONCLUSIONS: Ultrasound is a useful tool for depicting BP anatomy in the axillary fossa prior to block anesthesia. Median, ulnar, and radial nerves form a highly consistent triangular pattern around the axillary artery that is easily recognizable with US.