Dissectional Orientation: Morphological Variations of Teres Minor Muscle and its Nerve Supply

SUMMARY: The teres minor is one of the rotator cuff muscles that comprise the superior margin of the quadrangular space. Quadrangular space syndrome (QSS) refers to the entrapment or compression of the axillary nerve and the posterior humeral circumflex artery in the quadrangular space, often caused by injuries, dislocation of the shoulder joint, etc. Patients who fail the primary conservative treatments and have persistent symptoms and no pain relief for at least six months would be considered for surgical interventions for QSS. This cadaveric study of 17 cadavers (males: 9 and females: 8) was conducted in the Gross Anatomy Laboratory at the Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University. The cadavers were preserved in a 10 % formaldehyde solution and obtained ethical approval by the ethical commission of the Siriraj Institutional Review Board. The morphology of the teres minor muscle-tendon junction, the bifurcation type of the axillary nerve, and the length and number of the terminal branches of the nerve to the teres minor were documented. Specimens with quadrangular space contents and surrounding muscles that had been destroyed were excluded from the study. The results showed that 47.06 % of the specimens had type A bifurcation, 47.06 % had type B bifurcation, and the remaining 5.88 % had type C bifurcation. It was observed that 58.82 % had nonclassic muscle-tendon morphology, while 41.18 % were classic. The average length of the terminal branches of the nerve to the teres minor in males was 1.13 cm, with the majority having two branches. For females, many showed one terminal branch with an average length of 0.97 cm. Understanding the differences in anatomical variations can allow for a personalized treatment plan prior to quadrangular space syndrome surgical procedures and improve the recovery of postsurgical interventions for patients.

El músculo redondo menor es uno de los músculos del manguito rotador que comprende el margen superior del espacio cuadrangular. El síndrome del espacio cuadrangular (QSS) se refiere al atrapamiento o compresión del nervio axilar y la arteria circunfleja humeral posterior en el espacio cuadrangular, a menudo causado por lesiones, dislocación de la articulación humeral, entre otros. En los pacientes en los que fracasan los tratamientos conservadores primarios y presentan síntomas persistentes y ningún alivio del dolor durante al menos seis meses se considerarían para intervenciones quirúrgicas para QSS. Este estudio cadavérico de 17 cadáveres (hombres: 9 y mujeres: 8) se llevó a cabo en el Laboratorio de Anatomía Macroscópica del Departamento de Anatomía de la Facultad de Medicina del Hospital Siriraj de la Universidad Mahidol. Los cadáveres se conservaron en una solución de formaldehído al 10 % y obtuvieron la aprobación ética de la comisión ética de la Junta de Revisión Institucional de Siriraj. Se documentó la morfología de la unión músculo-tendón del músculo redondo menor, el tipo de bifurcación del nervio axilar y la longitud y el número de las ramas terminales del nervio para el músculo redondo menor. Se excluyeron del estudio los especímenes con contenido de espacios cuadrangulares y músculos circundantes que habían sido destruidos. Los resultados mostraron que el 47,06 % de los especímenes presentó bifurcación tipo A, el 47,06 % una bifurcación tipo B y el 5,88 % restante una bifurcación tipo C. Se observó que el 58,82 % presentaba una morfología músculo-tendinosa no clásica, mientras que el 41,18 % era clásica. La longitud pmedia de los ramos terminales del nervio hasta el músculo redondo menor en los hombres era de 1,13 cm, y la mayoría tenía dos ramos. En el caso de las mujeres, mostraron un ramo terminal con una longitud promedio de 0,97 cm. Comprender las diferencias en las variaciones anatómicas puede permitir un plan de tratamiento personalizado antes de los procedimientos quirúrgicos del síndrome del espacio cuadrangular y mejorar la recupe- ración de las intervenciones posquirúrgicas de los pacientes.

Modified Latarjet splitting subscapularis muscle under arthroscopy: an anatomical study based on axillary nerve, glenoid, and subscapularis muscle / 中国修复重建外科杂志

OBJECTIVE@#To testify the spatial relationship between the subscapularis muscle splitting window and the axillary nerve in modified arthroscopic Latarjet procedure, which could provide anatomical basis for the modification of the subscapularis muscle splitting.@*METHODS@#A total of 29 adult cadaveric shoulder specimens were dissected layer by layer, and the axillary nerve was finally confirmed to walk on the front surface of the subscapularis muscle. Keeping the shoulder joint in a neutral position, the Kirschner wire was passed through the subscapularis muscle from back to front at the 4 : 00 position of the right glenoid circle (7 : 00 position of the left glenoid circle), and the anterior exit point (point A, the point of splitting subscapularis muscle during Latarjet procedure) was recorded. The vertical and horizontal distances between point A and the axillary nerve were measured respectively.@*RESULTS@#In the neutral position of the shoulder joint, the distance between the point A and the axillary nerve was 27.37 (19.80, 34.55) mm in the horizontal plane and 16.67 (12.85, 20.35) mm in the vertical plane.@*CONCLUSION@#In the neutral position of the shoulder joint, the possibility of axillary nerve injury will be relatively reduced when radiofrequency is taken from the 4 : 00 position of the right glenoid (7 : 00 position of the left glenoid circle), passing through the subscapularis muscle posteriorly and anteriorly and splitting outward.

Neurotización del nervio circunflejo por vía axilar, estudio cadavérico / Neurotization of the circumflex nerve through an axillary approach, cadaveric study

Objetivo Confirmar factibilidad técnica de la neurotización del nervio axilar por la rama motora de la porción larga del tríceps con el fin de definir la anatomía quirúrgica de los nervios radial y axilar. Materiales y métodos Veinte hombros de cadáver fueron intervenidos para transferencia de la rama del Nervio Radial para la porción larga del tríceps a la rama anterior del Nervio Axilar por abordaje axilar. Se confirmó la escogencia correcta del nervio receptor por abordaje posterior. Resultados Se logró una disección adecuada de la primera rama motora del nervio radial del nervio axilar y de la rama anterior del Nervio Axilar. El origen de la rama motora se encontró en promedio a 3,8mm (+/- 7,3mm) distal al borde superior del tendón del dorsal ancho. El nervio axilar se encontró cefálico al borde superior del dorsal ancho a una distancia promedio de 11,3mm (+/-2,13mm) y distal al redondo menor 3.05mm (+/- 1,3mm), sutura con la primera rama del radial en el 100% de los casos sin tensión y se confirmó la adecuada transferencia en todos los casos. Conclusión La neurotización del nervio axilar con la primera rama del nervio radial se logró con éxito en el 100% por vía axilar. Este abordaje es adecuado, evitando tener que realizar cambios de posición a prono y doble abordaje, y si se requiere procedimientos adicionales de reconstrucción en el mismo tiempo quirúrgico tipo Oberlin y exploraciones supraclaviculares del plexo braquial se pueden realizar sin cambio de posición.

Objective To confirm the technical feasibility of neurotization of the axillary nerve by the motor branch of the long head of the triceps in order to define the surgical anatomy of the radial and axillary nerves. Materials and method Twenty cadaver shoulders were operated on for transfer of the radial nerve branch for the long head of the triceps to the anterior branch of the axillary nerve by axillary approach. The correct choice of the receiving nerve was confirmed by posterior approach. Results An adequate dissection of the first motor branch of the radial nerve of the axillary nerve and of the anterior branch of the Axillary Nerve was achieved, The origin of the motor branch was found on average at 3.8mm (+/−7.3mm) distal to the superior border of the latissimus dorsi tendon. The axillary nerve was found 11.3mm (+/−2.13mm) cephalad to the upper border of the latissimus dorsi and 3.05mm (+/−1.3mm) distal to the teres minor. A tensionless coaptation was obtained in all cases. Conclusion Neurotization of the axillary nerve with the first branch of the radial nerve was successfully achieved through the axillary approach. This approach is adequate, avoiding position change to prone and double approach, and if additional reconstruction procedures are required at the same surgical time, Oberlin type and supraclavicular explorations of the brachial plexus can be performed without changing position.

Contribution Of Axillary Nerve In The Innervation Of Long Head Of Triceps Brachii: A Cadaveric Study

Background: Traditionally the axillary nerve innervates the Deltoid and the Teres minor(TM) muscle. Axillarynerve injuries are common in shoulder dislocation, fracture surgical neck of humerus, brachial plexus injuriesand neuropathies. Traumatic injuries of axillary nerve have also shown weakness of Long head of triceps and insurgical practice, the nerve to long head of triceps is utilized for nerve transfer to neurotise the deltoid muscle inpatients with axillary nerve injuries. Hence the aim of the study was to find out the prevalence of contribution ofaxillary nerve to the innervation of Long head of triceps brachii (LHT).Materials and Methods: Nine embalmed adult human cadavers (bilaterally) and twelve disarticulated upperextremities were dissected. Total of thirty upper extremities were dissected. The axillary nerve was observedemerging from the quadrangular space. Anterior and posterior branches of axillary nerve were noted. Themuscular branches to deltoid, TM and LHT were traced to their point of innervation. The focus was on the branchof axillary nerve supplying the LHT. The branching configuration was classified into three types. Type I- posteriorbranch of axillary nerve supplying the LHT, Type II- Branch to TM supplying the LHT and Type III- A branch from thebifurcation of anterior & posterior branch of axillary nerve supplying LHT.Results: The present study showed that axillary nerve innervated the LHT in 8 out of 30 limbs (26.66%). Amongstthese, in 4 limbs(50%) posterior branch of axillary nerve supplied the LHT(type I ), in 3 limbs(37.5%) branch to TMsupplied the LHT(type II) and in 1 limb(12.5%) a branch from the bifurcation of axillary nerve into anterior andposterior branch supplied the LHT( type III). It was also observed that in 2 (6.66%) specimens, axillary nerve wasthe only supply to LHT and in 6 (20%) specimens both axillary nerve & radial nerve supplied the LHT and in theremaining 22 (73.3%) specimens, only the radial nerve supplied the LHT.Conclusion: Awareness of the variation of axillary nerve supplying the LHT is important for surgeons,orthopaedicians and anaesthetists for surgical treatment of traumatic nerve injuries.

Eficacia del tratamiento quirúrgico mediante neurotización radial en pacientes con lesión traumática aislada de nervio axilar / Efficacy of surgical treatment by radial nerve transfer in patients with traumatic isolated axillary nerve injury

Resumen: Objetivo: Determinar la eficacia del tratamiento quirúrgico mediante neurotización radial en pacientes con diagnóstico de lesión traumática aislada de nervio axilar. Material y métodos: Se presenta una serie de siete casos, seis hombres y una mujer, con promedio de edad de 51.6 años, con diagnóstico de lesión traumática aislada de nervio axilar tratados quirúrgicamente entre Enero 2013 y Diciembre 2016. Todos los pacientes fueron tratados mediante transferencia nerviosa de rama motora radial de la cabeza medial del tríceps, entre el sexto y decimoséptimo mes después del traumatismo, con un seguimiento mínimo de 12 meses. Se evaluó la eficacia del tratamiento mediante la Medical Research Council (MRC) y el cuestionario DASH. Resultados: En el análisis bivariado encontramos diferencias estadísticamente significativas con respecto al grado de mejoría de fuerza de rotación externa y de abducción medido por MRC preoperatoria y postoperatoria (p < 0.05). Los resultados también demostraron una significancia estadística en el rango de movimiento de abducción postoperatorio de hombro (p = 0.01). El cuestionario DASH demostró un porcentaje promedio de discapacidad de 20.29% después de 12 meses de seguimiento. Conclusión: La neurotización radial en pacientes con diagnóstico de lesión traumática aislada de nervio axilar proporciona un excelente grado de mejoría de fuerza de rotación externa y abducción, además de mejorar significativamente el rango de abducción del hombro; también se demostró, mediante cuestionario DASH, que el porcentaje de discapacidad es bajo.

Abstract: Purpose: To determine the efficacy of surgical treatment by radial nerve transfer in patients with a diagnosis of isolated axillary nerve traumatic injury. Material and methods: We present a series of seven cases, six men and one woman, with a mean age of 51.6 years, with a diagnosis of isolated traumatic axillary nerve injury between January 2013 and December 2016. All patients were treated by radial motor branch nerve transfer of the medial triceps head between the sixth and seventeenth months after trauma, with a minimum follow-up of 12 months. The efficacy of the treatment was evaluated by the Medical Research Council (MRC) and the DASH questionnaire. Results: In the bivariate analysis we found statistically significant differences regarding the degree of external rotation and abduction strength measured by preoperative and postoperative MRC (p < 0.05). The results also demonstrated a statistical significance in the range of postoperative shoulder abduction movement (p = 0.01). The DASH questionnaire showed an average percentage of disability of 20.29% after 12 months of follow-up. Conclusion: Radial nerve transfer in patients diagnosed with axillary nerve traumatic injury provides an excellent degree of improvement in external rotation and abduction strength, in addition to significantly improving the shoulder abduction range, it was also demonstrated by DASH questionnaire that the percentage disability is low.

Variations Of Origin And Distance Of Axillary Nerve: A Descriptive Study

Background–Axillary nerve, one of the terminal branches of posterior cord of brachial plexus is more prone for inju-ries. Lack of proper anatomical knowledge and variations of axillary nerve leads to risk of nerve injuries. The present study describes the origin of axillary nerve, its distance of origin from tip of coracoids process. Method: Thirty brachi-al plexuses from fifteen formalin fixed human cadavers of both the sexes were studied by dissection method. Origin and branching pattern of axillary nerve and its distance of origin from the anteromedial aspect of tip of coracoid pro-cess & posterolateral aspect of acromion process was recorded. Results:Out of the 30 specimens studied, axillary nerve was originating from the posterior cord of brachial plexus in 90% of specimens, remaining 10% specimens showed a common trunk of origin of axillary nerve from posterior cord of brachial plexus. The mean distance of origin of axillary nerve from the anteromedial aspect of tip of coracoid process and posterolateral aspect of acromion process is 3.98cm & 6.30cm respectively. The axillary nerve terminated into anterior and posterior branch within quadrangular space in 29 specimens. In one specimen articular branch for shoulder joint was not directly arising from axillary nerve instead it is arising from anterior branch of axillary nerve. Conclusion: In studied population Axil-lary nerves display variations in the origin and distance of origin. Knowledge of this variation in axillary nerve is very important to clinicians, anaesthetists and orthopaedic surgeons during surgical exploration of neck, axilla and upper arm, shoulder dislocation, infraclavicular brachial plexus block and fracture of surgical neck of humerus.

Anatomical Variations Of The Axillary Nerve: A Cadaveric Study

Background: Axillary nerve is one of the most common nerves which is prone to iatrogenic injuries (6% of all thebrachial plexus injuries). Knowledge of the anatomical variations of the axillary nerve in respect to its originfrom the posterior cord of brachial plexus, its site of division into anterior and posterior branch and its mode ofsupply to the deltoid muscle is highly important for anatomists, orthopedic surgeons, radiologists and anesthetistsfor proper exploration of the axillary region.Material and Methods: The study was carried out in the Department of Anatomy, Institute of PostgraduateMedical Education and Research, Kolkata, West Bengal. The sample size was 50 upper limbs of 25 formalinhardened human cadavers of both sexes.Results: Out of 50 samples, in 16% cases the Axillary nerve took origin as a common trunk. Regarding the site ofdivision of the axillary nerve into anterior and posterior branches it was found to be above the quadrangularspace in 12% cases and within the quadrangular space in 88% cases. . Regarding the mode of supply of thedeltoid muscle it was seen that the anterior part of the deltoid was supplied by the anterior division of theaxillary nerve in 100% cases; middle part of the deltoid solely by anterior division of the axillary nerve in 60%cases and in remaining 40% cases both from anterior and posterior branch i.e. dual supply (fig-3); the posteriorpart of the deltoid was seen to be supplied by the posterior branch in 100% cases.Conclusion: The knowledge of variations of axillary nerve is very important for anatomists, aneasthesists,orthopaedic surgeons and general physicians during surgical interventions of the axilla and intra-muscularinjections to the deltoid muscle.

Axillary nerve neurotization by a triceps motor branch: comparison between axillary and posterior arm approaches / Neurotização do nervo axilar por um ramo do tríceps: comparação entre acesso axilar e posterior

ABSTRACT Objectives: This study is aimed at comparing the functional outcome of axillary nerve neurotization by a triceps motor branch through the axillary approach and posterior arm approach. Methods: The study included 27 patients with post-traumatic brachial plexus injury treated with axillary nerve neurotization by a triceps motor branch for functional recovery of shoulder abduction and external rotation. The patients were retrospectively evaluated and two groups were identified, one with 13 patients undergoing axillary nerve neurotization by an axillary approach and the second with 14 patients using the posterior arm approach. Patients underwent assessment of muscle strength using the scale recommended by the British Medical Research Council, preoperatively and 18 months postoperatively, with useful function recovery considered as grade M3 or greater. Results: In the axillary approach group, 76.9% of patients achieved useful abduction function recovery and 69.2% achieved useful external rotation function recovery. In the group with posterior arm approach, 71.4% of patients achieved useful abduction function recovery and 50% achieved useful external rotation function recovery. The difference between the two groups was not statistically significant (p = 1.000 for the British Medical Research Council abduction scale and p = 0.440 for external rotation). Conclusion: According to the British Medical Research Council grading, axillary nerve neurotization with a triceps motor branch using axillary approach or posterior arm approach shows no statistical differences.

RESUMO Objetivos: Comparar o resultado funcional da neurotização do nervo axilar por um ramo motor do tríceps através do acesso axilar e do acesso posterior. Métodos: Foram incluídos no estudo 27 pacientes com lesão pós-traumática de plexo braquial submetidos à neurotização do nervo axilar por um ramo motor do tríceps para recuperação funcional do ombro de 2010 a 2014. Os pacientes foram avaliados e dois grupos foram identificados, um com 13 pacientes submetidos a neurotização do nervo axilar por um acesso axilar e o segundo com 14 pacientes nos quais foi usada a via de acesso posterior. Os pacientes foram submetidos a avaliação da força muscular com a escala preconizada pelo British Medical Research Council (BMRC) no pré-operatório e com 18 meses de pós-operatório, foi considerada força motora efetiva graduação M3 ou maior. Resultados: No grupo que fez o acesso axilar, 76,9% dos pacientes obtiveram força motora efetiva de abdução e 69,2% de rotação externa. Já no grupo com acesso posterior, 71,4% dos pacientes conseguiram força motora efetiva de abdução e 50% de rotação externa. A diferença entre os dois grupos não foi estatisticamente significante (p = 1,000 para escala BMRC de abdução e p = 0,440 para rotação externa). Conclusão: Na avaliação da graduação de força na escala BRMC, o uso do acesso axilar para neurotização de um ramo motor do tríceps para o nervo axilar não apresenta diferenças estatísticas em relação ao uso do acesso posterior.

Risk of Axillary Nerve Injury in Standard Anterolateral Approach of Shoulder: Cadaveric Study

@#Introduction:The anterolateral acromion approach of the shoulder is popular for minimally invasive plate osteosynthesis (MIPO) technique. However, there are literatures describing the specific risks of injury of the axillary nerve using this approach. Nevertheless, most of the studies were done with Caucasian cadavers. So, the purpose of this study was to evaluate the risk of iatrogenic axillary nerve injury from using the anterolateral shoulder approach and further investigate the location of the axillary nerve, associated with its location and arm length in the Asian population that have shorter arm length compared to the Caucasian population. Materials and Methods:Seventy-nine shoulders in fourtytwo embalmed cadavers were evaluated. The bony landmarks were drawn, and a vertical straight incision was made 5cm from tip of the acromion (anterolateral approach), to the bone. The iatrogenic nerve injury status and the distance between the anterolateral edge of the acromion to the axillary nerve was measured and recorded. Results: In ten of the seventy-nine shoulders, the axillary nerve were iatrogenically injured. The average anterior distance was 6.4cm and the average arm length was 30.2cm. The anterior distance and arm length ratio was 0.2. Conclusion: Our results demonstrated that the recommended safe zone at 5cm from tip of acromion was not suitable with Asian population due to shorter arm length, compared to Caucasian population. The location of axillary nerve could be predicted by 20% of the total arm-length.

Re-definition of position and calculation of safe area for axillary nerve in deltoid muscle with its clinical relevance: a cadaveric study / 대한해부학회지

Several authors have made efforts to define the position of the axillary nerve within deltoid muscle and to calculate the so called safe area for this nerve but it still remains a matter of debate. The primary aim of the study was to investigate the acromio-axillary (AA) distance and its correlation with upper arm length. The secondary aim was to re-define the safe area for axillary nerve within deltoid muscle. Sixty shoulders of thirty adult human cadavers were dissected using standard methods. The distance from the anterior and posterior edge of acromion to the upper border of the course of the axillary nerve was measured and recorded as anterior and posterior AA distance respectively. Correlation analysis was done between the upper arm length and AA distance for each limb. The ratios between anterior and posterior AA distance and upper arm length were calculated and mentioned as anterior index and posterior index, respectively. The mean of anterior and posterior AA distance was 5.22 cm and 4.17 cm, respectively. The mean of upper arm length was 29.30 cm. The means of anterior index and posterior indices were 0.18 and 0.14, respectively. There was a significant correlation between upper arm length and both the anterior and posterior AA distance. The axillary nerve was found to lie at variable distance from the acromion. The minimum AA distance was found to be 3.50 cm. So this should be considered as the maximum permissible length of the deltoid split. Upper arm length has strong correlation with both anterior and posterior AA distances. The ideal safe area for the axillary nerve was found to be a quadrangular area above it and the size of which depends on the length of the upper arm.

MIPPO and ORIF for the treatment of elderly proximal humerus fractures of type Neer II:a case control study / 中国骨伤

<p><b>OBJECTIVE</b>To compare the clinical efficacy of minimally invasive percutaneous plate osteosynthesis(MIPPO)and open reduction and internal fixation (ORIF) in treating senile NEER IIproximal humerus fractures.</p><p><b>METHODS</b>From March 2014 to March 2016, 46 elderly patients with Neer II proximal humerus fractures were retrospectively reviewed. Among them, 20 patients in MIPPO group included 9 males and 11 females with an average age of (70.4±4.4) years old; while 26 patients in ORIF group included 11 males and 15 females with an average age of (70.9±4.0) years old. The length of hospital stay, times of fluoroscopy, beginning time of function rehabilitation, healing time of fracture, Constant Murley score of the shoulder joint at 3, 6, 12 months after operation and complications were observed and compared.</p><p><b>RESULTS</b>All patients were followed up for 12 to 24 months with an average of 16.8±3.7. The healing time of fracture, beginning time of function rehabilitation in MIPPO group were(13.0±0.8) weeks, (3.0±0.9) days respectively and shorter than those in ORIF group which were (13.8±1.4) weeks and(6.8±1.3) days. The times of fluoroscopy in MIPPO group was 19.2±3.7 and more than that in ORIF group which was 12.1±3.4. At 3 and 6 months after operation, Constant Murley score in MIPPO group were 81.3±3.9, 86.6±5.4 and more than that in ORIF group which were 69.5±6.6, 80.5±6.7. There were no differences between two groups in the length of hospital stay, Constant Murley score at 12 months after operation and grading at the final follow-up. There was one fracture redisplacement in each group. And 1 case of axillary nerve injury in MIPPO group, 2 cases of delayed union in ORIF group. No incision infection, screw loosening or plate break was found.</p><p><b>CONCLUSIONS</b>MIPPO and ORIF are both effective in treating Neer II proximal humeral fractures. MIPPO technique has the advantages of faster recovery, earlier rehabilitative exercise and better shoulder function. The disadvantages are more exposure to radiationd and the possibility of axillary nerve injure.</p>

Inervación de la cabeza larga del músculo tríceps braquial / Innervation of the long head of triceps brachii muscle

Clásicamente, la inervación del músculo tríceps braquial se atribuye al nervio radial. Sin embargo, reportes clínicos han observado parálisis de la cabeza larga del músculo tríceps braquial posterior a lesiones del nervio axilar, ocurridas luego de una luxación de la articulación glenohumeral, poniendo en duda la inervación de la cabeza larga del músculo tríceps braquial. El objetivo del presente estudio es verificar la inervación de la cabeza larga del músculo tríceps braquial por parte del nervio axilar. Se disecaron 12 regiones posteriores de hombro y brazo, previamente fijadas en solución fijadora conservadora, identificando ramos de inervación del nervio axilar hacia la cabeza larga del músculo tríceps braquial, luego se obtuvieron muestras para estudio histológico con Hematoxilina-Eosina. Fue posible identificar en todos los casos ramos del nervio axilar, penetrando en la mitad superior de la cabeza larga del músculo tríceps braquial. El estudio histológico mostró una imagen compatible con tejido nervioso en todas las muestras analizadas. Estos resultados contrastan con las descripciones realizadas en textos clásicos respecto a la inervación del músculo tríceps braquial, el cual podría presentar una doble inervación proveniente de los nervios radial y axilar, o una inervación diferente para cada cabeza. Los hallazgos presentados aportan información a la hora de analizar las lesiones del nervio axilar post luxaciones de hombro, al realizar procedimientos quirúrgicos en esta región o en la planificación de la rehabilitación de estos pacientes.

Primarily, innervation of the triceps brachii muscle has been attributed to the axillary nerve. However, clinical reports have observed paralysis from the long head of the triceps brachii muscle following axillary nerve lesions which occurred after dislocation of the glenohumeral joint. This has raised questions about the innervation of the long head of triceps brachii muscle. The objective of this study was to verify the innervation of the long head of the triceps brachii muscle by the axillary nerve. Twelve previously fixed posterior areas of shoulder and arm were dissected and branches of innervation of the axillary nerve towards the long head of triceps brachii muscle were identified. Subsequently, samples were taken for histological hematoxylin-eosin study. In all cases, we observed branches of the axillary nerve penetrating the upper half of the long head of the triceps brachii muscle. The histological study showed an image compatible with nerve tissue in each sample analyzed. The results contrast with the description in classic texts regarding innervation of the triceps brachii muscle, which could present with double innervation from the radial and axillary nerves, or a separate innervation for each head. These results provide information for axillary nerve lesion analysis following shoulder dislocation, at the time of performing surgical procedures in the area, or when planning rehabilitation for these patients.

Radial Medial Head Triceps Branch Transfer to Axillary Nerve by Axillary Approach / Acesso ao nervo axilar por via axilar anterior

Objective To describe axillary approach for axillary nerve transfer with radial nerve branch in brachial plexus lesions. Methods Six patients aged 24 to 54 (mean 30) years with traumatic superior trunk brachial plexus injury underwent axillary approach between October 2011 and April 2012. On physical examination prior to surgery, they could not perform shoulder abduction, external rotation, or elbow flexion. Surgical approach was made through axillary pathway without any muscular section. The transfer was done with the radial branch to the medial head of triceps. In addition to transfer to axillary nerve, each patient had spinal accessory nerve transferred to suprascapular nerve and ulnar nerve fascicle transferred to musculocutaneous nerve. Conclusion The axillary approach allows easy access to axillary nerve and, therefore, is a feasible pathway to transferences involving this nerve.(AU)

Objetivo Apresentar via axilar por transferência de nervo axilar com ramo de nervo radial em lesões do plexus braquial. Métodos Seis pacientes com idade entre 24 e 54 anos (média de 30) com lesão braquial traumática do plexus no tronco superior submetidos a via axilar entre outubro de 2011 e abril de 2012. Em exame físico pré-cirúrgico, não foram capazes de executar abdução do ombro, rotação externa, ou flexão do cotovelo. Abordagem cirúrgica foi realizada por passagem axilar sem qualquer seção muscular. A transferência ocorreu como ramo radial do tríceps medial da cabeça. Somada à transferência ao nervo axilar, cada paciente teve nervo acessório espinhal transferido para o nervo supraescapular, e o fascículo do nervo ulnar transferido para o nervo musculocutâneo. Conclusão A via axilar facilita acesso ao nervo axilar e, por isso, é um caminho factível para transferências envolvendo este nervo.(AU)

Compressive Partial Neuropathy of Axillary Nerve Resulting from Antero-Inferior Paralabral Cyst in an Adolescent Overhead Athlete / 대한스포츠의학회지

Paralabral cysts of the shoulder are rare, and there are few reports available that describe anteroinferior paralabral cysts arising from a detached antero-inferior glenoid labral tear without shoulder instability. We report an antero-inferior labral tear without shoulder instability in adolescent overhead athlete associated with paralabral cyst that leads to axillary nerve neurapraxia. Although nonoperative management of such labral lesions may provide symptoms of relief, it may not be enough for the athlete to return to the game. However, surgical treatment in this case provides successful recovery and rapid return to playing baseball play without having to worry about the progression of muscle denervation.

Variation in Branching Pattern of Axillary Nerve.

In our present case the axillary nerve on both sideswas arising from posterior cord. About 2.5cm fromits origin at the lateral border of subscapularis, it gave 2 branches i.e anterior and posterior branch. The axillary nerve branched before entering the quadrangular space. Knowledge of the precise relationship of the branches of the axillary nerve, its relationship to the shoulder capsule and its common variations within deltoid muscle is necessary for performing surgical procedures over shoulder and reduce the incidence of iatrogenic nerve damage.

Complications and Outcomes of Minimally Invasive Percutaneous Plating for Proximal Humeral Fractures

BACKGROUND: The minimally invasive plate osteosynthesis (MIPO) technique using periarticular locking plates may be a good option for the repair of displaced proximal humeral fractures. However, axillary nerve complications related to this technique may be underestimated. The purpose of this study is to evaluate the outcomes of the minimally invasive plating, focusing on the complications. METHODS: The records of 21 consecutive patients treated for proximal humerus fractures using the MIPO technique with locking plates were retrospectively reviewed. These patients were treated between March 2009 and March 2011 with a minimum one-year follow-up. The clinical function, complications, and radiological bony union were evaluated. RESULTS: All of the patients, with one exception, showed at least 90 degrees of flexion and abduction at the shoulder joint six months postoperatively. The average Constant scores at three months, six months, and one year follow-ups were 74.0 (range, 62 to 90), 79.4 (range, 64 to 91), and 82.7 (range, 66 to 92), respectively. All of the patients achieved bony union within the average of 3.2 months (range, 2 to 6 months). There was one case of delayed union, one case of intra-articular screw penetration, and one case of axillary nerve paresis (incomplete injury), which did not completely recover during the one year of follow-up. CONCLUSIONS: The MIPO technique using periarticular locking plates is a useful option for the treatment of selected cases of displaced proximal humeral fractures. However, nerve complications such as axillary nerve paresis should be considered along with implant-related complications when choosing patients for minimally invasive plating.

A unique unreported anomalous muscle of scapular region and its clinical implications - A case report.

Back ground: It is a well documented fact that the lower border of spine of scapula gives origin to deltoid muscle only. We report a case of anomalous muscle arising from the medial aspect of lower border of spine of scapula in the left upper extremity of a 59 year old male cadaver. The anomalous muscle is innervated by axillary nerve which also gave a motor twig to the long head of triceps brachii. This variation was unilateral. The morphological, embryological and clinical significance of the anomalous muscle is discussed.

Isolated Injury of the Axillary Nerve Branch to Teres Minor Muscle Following After Traumatic Posterior Instability of Shoulder

We describe a case of a 23-year-old man who presented with posterior instability of the right shoulder following trauma. Focal neuropathy of the axillary nerve branch to the teres minor muscle was diagnosed electrophysiologically. A shoulder magnetic resonance image revealed fatty atrophy of the teres minor muscle with sparing of the deltoid, supraspinatus, infraspinatus, and subscapularis muscles. To our knowledge, this is the first case of selective injury of the branch of the axillary nerve to the teres minor muscle to be described in Korea.

Axillary Nerve Injury after Swimming with Butterfly Stroke: A case report

Most of axillary nerve injury develops after dislocation of glenohumeral joint, proximal humeral fracture and direct blow to the deltoid muscle. Some cases in volleyball players and athletes playing contact sports like hockey, football have been reported. But axillary nerve injury after swimming with butterfly stroke has not been reported previously. We experienced a 34 year old female who had weakness in abduction and sensory impairment in lateral aspect of right arm after butterfly stroke. She was transferred from local clinic to our Rehabilitation Department because symptoms were not improved despite conservative treatment. We diagnosed her as axillary nerve injury by typical clinical manifestations and electrodiagnostic study. Additionally, we detected type II superior laburum anterior posterior lesion combined with axillary nerve injury in shoulder magnetic resonance image. We should consider possibility of axillary nerve injury in a patient with shoulder pain and weakness after swimming like butterfly stroke.

Microanatomy and histological study of the fascicular group to deltoid muscle in axillary nerve at the level of quadrilateral zone / 中华创伤骨科杂志

Objective To observe and study the distribution and histological feature of the fascicular groups to deltoid muscle in axillary nerve at the level of quadrilateral zone. Methods 12 adult human cadavers (24 upper limbs)embalmed by formalin were used,, and microsurgical longitudinal contradissection of the axillary nerves by tracing their terminal branches were processed. At the level of quadrilateral zone,distrabution of the fscicular groups to deltoid muscle in the never trunk were recorded and their diameters were measured;Another 6 upper extremities (3 right and 3 left) of fresh-frozen human cadavers were obtained.Axillary nerves and their fascicular groups were exposured, and the segments at the level of qusdrilateral zone gotten, then histological cross section was done, acetycholinesterase (ACHE) stained with the method of Karnovsky Roots and myelin stained with the method of Loyezs. Defferent never fibres were distinguished under microscope and the fiber number was counted with IAS . Results At the level of quadrilateral zone,fasciculars were divided into two groups.The fascicular group of anterior branch to deltoid muscle was in the lateral of the nerve trunk . Its cross sectional area was (2.449?1.327)mm2 ,occupied 55.4%?9.3%of the axillary nerve trunk ;Its most fibers were motor fibers;The number of fibers is (2112?631), occupied 45.6 %?1.1%of all fibers of axillary nerve . Conclusions In the treatment of root avulsion of brachial plexus injury, selective suture donor nerve with the lateral fascicular group should be processed to repair the function of shoulder abduction,fibers loss would be reduced and rate of functional restoration improved .