Lesión electromiográfica del nervio axilar en fracturas del extremo proximal del húmero. Estudio prospectivo, observacional, analizando el patrón de fractura / Electromyographic axillary nerve injury in fractures of the proximal humerus: Prospective, observational study, analysing the fracture pattern

Objetivo: Descripción y análisis de la relación entre las fracturas de húmero proximal y la lesión traumática del nervio axilar circunflejo. Material y método: Estudio prospectivo, observacional, de una serie de casos consecutivos de fracturas de extremo proximal de húmero. Se realizó valoración radiográfica, clasificando las fracturas según el sistema AO (Arbeitsgemeinshaft für Osteosynsthesefragen, Asociación de Grupo de Trabajo para el Estudio de la Fijación Interna de las Fracturas), y electromiografía (EMG) para la evaluación de la lesión del nervio axilar. Resultados: De 105 casos consecutivos de fracturas de húmero proximal, 31 pacientes cumplían los criterios de inclusión. Muestra: 86% mujeres y 14% hombres con edad media de 71,8 años (30-96 años). De los pacientes incluidos en el estudio, 58% presentó una EMG normal o leve axonotmesis, 23% presentó neuropatía del nervio axilar sin denervación muscular y 19%, lesión con denervación del nervio axilar. Los pacientes que sufrieron fracturas complejas de húmero proximal (AO11B y AO11C) tuvieron más riesgo de presentar lesiones tipo neuropatía axilar con denervación muscular en la EMG, siendo esta relación estadísticamente significativa (p < 0,001). Conclusiones: Los pacientes que sufren fracturas complejas de húmero proximal (AO11B y AO11C) tienen más riesgo de presentar lesiones tipo neuropatía axilar con denervación muscular en la EMG (p < 0,001).(AU)

Objective: Description and analysis of the relation between the proximal humerus fracture patterns and the traumatic injury of the axillary nerve. Material and method: Prospective, observational study of a consecutive case series that analyzed proximal humerus fractures. Radiographic evaluation was performed, and AO (Arbeitsgemeinshaft für Osteosynsthesefragen) system was used to classify the fractures. Electromyography was used to diagnose the axillary nerve injury. Results: Thirty-one patients on 105 who had a proximal humerus fracture met inclusion criteria. Eighty-six percent of the patients included were women and 14% men. The mean age was 71.8 years (30–96 years). Of the patients included in the study, 58% had normal or mild axonotmesis EMG, 23% had axillary nerve neuropathy without muscle denervation and 19% had injury with axillary nerve denervation. Patients who suffered complex fractures of the proximal humerus (AO11B and AO11C) had a higher risk of presenting axillary neuropathy type lesions with muscle denervation in the EMG, this relationship being statistically significant (p<0.001). Conclusion: Patients who have more risk on presenting axillary nerve neuropathy with muscle denervation in electromyography are those who present complex proximal humerus fractures AO11B and AO11C (p<0.001).(AU)

[Translated article] Electromyographic axillary nerve injury in fractures of the proximal humerus: Prospective, observational study, analysing the fracture pattern / Lesión electromiográfica del nervio axilar en fracturas del extremo proximal del húmero. Estudio prospectivo, observacional, analizando el patrón de fractura

Objetivo: Descripción y análisis de la relación entre las fracturas de húmero proximal y la lesión traumática del nervio axilar circunflejo. Material y método: Estudio prospectivo, observacional, de una serie de casos consecutivos de fracturas de extremo proximal de húmero. Se realizó valoración radiográfica, clasificando las fracturas según el sistema AO (Arbeitsgemeinshaft für Osteosynsthesefragen, Asociación de Grupo de Trabajo para el Estudio de la Fijación Interna de las Fracturas), y electromiografía (EMG) para la evaluación de la lesión del nervio axilar. Resultados: De 105 casos consecutivos de fracturas de húmero proximal, 31 pacientes cumplían los criterios de inclusión. Muestra: 86% mujeres y 14% hombres con edad media de 71,8 años (30-96 años). De los pacientes incluidos en el estudio, 58% presentó una EMG normal o leve axonotmesis, 23% presentó neuropatía del nervio axilar sin denervación muscular y 19%, lesión con denervación del nervio axilar. Los pacientes que sufrieron fracturas complejas de húmero proximal (AO11B y AO11C) tuvieron más riesgo de presentar lesiones tipo neuropatía axilar con denervación muscular en la EMG, siendo esta relación estadísticamente significativa (p < 0,001). Conclusiones: Los pacientes que sufren fracturas complejas de húmero proximal (AO11B y AO11C) tienen más riesgo de presentar lesiones tipo neuropatía axilar con denervación muscular en la EMG (p < 0,001).(AU)

Objective: Description and analysis of the relation between the proximal humerus fracture patterns and the traumatic injury of the axillary nerve. Material and method: Prospective, observational study of a consecutive case series that analyzed proximal humerus fractures. Radiographic evaluation was performed, and AO (Arbeitsgemeinshaft für Osteosynsthesefragen) system was used to classify the fractures. Electromyography was used to diagnose the axillary nerve injury. Results: Thirty-one patients on 105 who had a proximal humerus fracture met inclusion criteria. Eighty-six percent of the patients included were women and 14% men. The mean age was 71.8 years (30–96 years). Of the patients included in the study, 58% had normal or mild axonotmesis EMG, 23% had axillary nerve neuropathy without muscle denervation and 19% had injury with axillary nerve denervation. Patients who suffered complex fractures of the proximal humerus (AO11B and AO11C) had a higher risk of presenting axillary neuropathy type lesions with muscle denervation in the EMG, this relationship being statistically significant (p<0.001). Conclusion: Patients who have more risk on presenting axillary nerve neuropathy with muscle denervation in electromyography are those who present complex proximal humerus fractures AO11B and AO11C (p<0.001).(AU)

Electromyographic axillary nerve injury in fractures of the proximal humerus: Prospective, observational study, analysing the fracture pattern. / Lesión electromiográfica del nervio axilar en fracturas del extremo proximal del húmero. Estudio prospectivo, observacional, analizando el patrón de fractura.

OBJECTIVE: Description and analysis of the relation between the proximal humerus fracture patterns and the traumatic injury of the axillary nerve. MATERIAL AND METHOD: Prospective, observational study of a consecutive case series that analyzed proximal humerus fractures. Radiographic evaluation was performed, and AO (Arbeitsgemeinshaft für Osteosynsthesefragen) system was used to classify the fractures. Electromyography was used to diagnose the axillary nerve injury. RESULTS: Thirty-one patients on 105 who had a proximal humerus fracture met inclusion criteria. Eighty-six percent of the patients included were women and 14% men. The mean age was 71.8 years (30-96 years). Of the patients included in the study, 58% had normal or mild axonotmesis EMG, 23% had axillary nerve neuropathy without muscle denervation and 19% had injury with axillary nerve denervation. Patients who suffered complex fractures of the proximal humerus (AO11B and AO11C) had a higher risk of presenting axillary neuropathy type lesions with muscle denervation in the EMG, this relationship being statistically significant (p<0.001). CONCLUSION: Patients who have more risk on presenting axillary nerve neuropathy with muscle denervation in electromyography are those who present complex proximal humerus fractures AO11B and AO11C (p<0.001).

[Translated article] Electromyographic axillary nerve injury in fractures of the proximal humerus: Prospective, observational study, analysing the fracture pattern.

OBJECTIVE: Description and analysis of the relation between the proximal humerus fracture patterns and the traumatic injury of the axillary nerve. MATERIAL AND METHOD: Prospective, observational study of a consecutive case series that analysed proximal humerus fractures. Radiographic evaluation was performed, and AO (Arbeitsgemeinshaft für Osteosynsthesefragen) system was used to classify the fractures. Electromyography was used to diagnose the axillary nerve injury. RESULTS: Thirty-one patients on 105 who had a proximal humerus fracture met inclusion criteria. Eighty-six percent of the patients included were women and 14% men. The mean age was 71.8 years (30-96 years). Of the patients included in the study, 58% had normal or mild axonotmesis EMG, 23% had axillary nerve neuropathy without muscle denervation and 19% had injury with axillary nerve denervation. Patients who suffered complex fractures of the proximal humerus (AO11B and AO11C) had a higher risk of presenting axillary neuropathy type lesions with muscle denervation in the EMG, this relationship being statistically significant (p<0.001). CONCLUSION: Patients who have more risk on presenting axillary nerve neuropathy with muscle denervation in electromyography are those who present complex proximal humerus fractures AO11B and AO11C (p<0.001).