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Os acromiale

Patient-facing topic on os acromiale — failed fusion of an acromial ossification centre that may cause shoulder pain and contribute to subacromial impingement.

Updated Sep 2026
Una ilustración dibujada a mano que muestra el acromion y el hueso acromial, el cual aparece como un fragmento óseo separado que no se ha fusionado.
Os acromiale: durante el desarrollo esquelético, la porción anterior del acromion no se fusionó con el resto del acromion. Kieran Hirpara 4.0

Esta página se tradujo automáticamente y todavía no la ha revisado un médico. La versión en inglés es la versión oficial.

Qué está sintiendo

La mayoría de las personas con un acromion no fusionado nunca experimentan síntomas relacionados con ello. Se trata de un pequeño fragmento óseo en la parte superior del hombro que no se fusionó con el resto del omóplato durante el crecimiento. Cuando sí genera molestias, el dolor se localiza en la parte frontal y lateral de la parte superior del hombro, justo sobre ese fragmento óseo no fusionado. Esa zona suele ser sensible al tacto.

El dolor tiende a intensificarse al levantar el brazo por encima de la cabeza. Estirarse para alcanzar un estante alto, colgar ropa para secar o pintar el techo pueden desencadenarlo. Los nadadores y atletas que realizan lanzamientos también lo notan durante su actividad deportiva. El dolor se produce porque el fragmento óseo no fusionado se mueve ligeramente al usar el hombro, o porque presiona los tejidos cercanos al levantar el brazo.

Además del dolor, es posible que sienta debilidad en el hombro. Levantar el brazo hacia adelante quizás no sea posible hasta la misma altura que antes. Algunas personas también perciben una sensación de “traba” al mover el hombro.

Un fragmento óseo no fusionado y estable puede volverse doloroso tras un golpe o una caída sobre ese hombro.

Si el reposo, el cambio de actividades o una inyección de esteroides no han aliviado el dolor, vale la pena examinar ese fragmento óseo no fusionado. Una radiografía tomada desde ciertos ángulos puede mostrarlo, aunque es fácil pasarlo por alto en las imágenes estándar. Un escáner también puede revelar hinchazón en la zona, lo cual indica que ese es el origen del dolor.

En la mayoría de los casos, los fragmentos óseos no fusionados no causan síntomas y no requieren ningún tratamiento.

¿Qué está ocurriendo realmente?

La escápula cuenta con una especie de repisa ósea en su parte superior llamada acromion; esta forma un “techo” sobre la articulación del hombro. Durante el crecimiento, esta repisa se forma a partir de tres fragmentos óseos: la base, la parte central y la punta. En la mayoría de las personas, estos fragmentos se unen hasta formar un solo hueso para la edad adulta. Sin embargo, en algunas personas uno de esos fragmentos nunca se fusiona; ese fragmento no fusionado se conoce como os acromiale.

El espacio entre los fragmentos se rellena con tejido fibroso resistente en lugar de hueso; puede imaginarse como una bisagra que nunca se atornilló por completo. Este fragmento puede moverse ligeramente cuando los grandes músculos del hombro tiran de él. Cada vez que levanta el brazo, esos músculos tiran del fragmento suelto, provocando una ligera flexión. Este movimiento, junto con la presión que ejerce sobre el tejido subyacente, es la causa de su dolor.

El “techo” del hombro también influye en lo que se encuentra debajo de él. El manguito rotador, una estructura formada por fibras tendinosas que estabiliza la articulación, discurre bajo dicho techo. Si el fragmento óseo suelto se desplaza o presiona hacia abajo al levantar el brazo, puede reducir el espacio necesario para el tendón; este estrechamiento se denomina pinzamiento. Es la misma razón por la que el brazo puede sentirse débil o “travado” al moverse.

En ocasiones, el fragmento no fusionado permanece inmóvil durante años sin causar ningún problema. No obstante, un golpe o una caída sobre el hombro puede activarlo, haciendo que ese espacio previamente inofensivo de pronto cause dolor.

Un último dato relevante: muchas personas presentan simultáneamente un os acromiale y un problema en el manguito rotador. Ambos suelen aparecer juntos; sin embargo, la presencia de uno no implica automáticamente que sea el responsable de su dolor. Por eso su cirujano evalúa el cuadro clínico en su totalidad —incluyendo la localización de la sensibilidad y los resultados de las pruebas de imagen— antes de determinar cuál es la verdadera causa de sus síntomas.

Qué podemos hacer al respecto

El Dr. Kieran Hirpara, cirujano de extremidades superiores en el Mater Private Hospital Rockhampton, comienza con las opciones menos invasivas que se adapten a su condición. Por lo general, los pacientes son derivados a nuestra clínica por su médico de cabecera; si un fisioterapeuta le ha sugerido que nos consulte, igualmente necesitará una derivación de su médico de cabecera para poder acceder al reembolso de Medicare. En su primera visita, tomamos su historia clínica, examinamos su hombro y solicitamos estudios de imagen cuando resultan necesarios. Una radiografía tomada desde ciertos ángulos suele mostrar el fragmento óseo que no se ha fusionado. Un escáner aporta más detalles sobre los tendones y los tejidos que rodean la articulación.

En el caso de un proceso doloroso en el acromion, el tratamiento suele iniciarse sin cirugía. Puede descansar el hombro durante un breve período y modificar la forma en que lo utiliza, manteniendo el brazo por debajo de la altura del hombro siempre que sea posible. La fisioterapia busca aliviar el dolor y fortalecer los músculos que sostienen el hombro. Por lo general, le pedimos que pruebe este tratamiento durante un tiempo razonable antes de considerar cualquier otra opción.

Los analgésicos y los antiinflamatorios, que reducen la inflamación, pueden ayudarle a superar los episodios de dolor. Su médico de cabecera podrá orientarle sobre cuál es el tratamiento más adecuado para usted.

Si estas medidas no le brindan suficiente alivio, entonces vale la pena considerar la cirugía. La operación consiste en unir el fragmento óseo no fusionado al resto del omóplato, de modo que ya no se mueva al levantar el brazo. Para ello, lo mantenemos en su posición mientras cicatriza, utilizando una pequeña placa metálica o una tira de tejido enrollada alrededor del hueso. El objetivo es lograr una unión sólida que permita nuevamente a los músculos actuar sobre una base estable. Analizaremos si esta intervención es adecuada para su hombro; la decisión final la tomará usted junto con nosotros.

Qué esperar

La mayoría de los fragmentos óseos no fusionados nunca causan problemas y no requieren ningún tratamiento. Si el suyo ha permanecido estable durante años, es probable que siga así. Sin embargo, un golpe o una caída sobre el hombro puede activarlo, y el dolor suele desaparecer con reposo y medidas sencillas.

En el caso de un os acromiale doloroso, el tratamiento suele comenzar sin cirugía. El reposo, cambios en las actividades y la fisioterapia suelen ser suficientes para muchas personas. Si estos pasos no le brindan suficiente alivio, una cirugía para unir el fragmento no fusionado al resto del omóplato puede reducir sus síntomas y mejorar la función del hombro. Los resultados de esta operación suelen ser buenos, especialmente cuando el fragmento es grande o se mueve excesivamente.

Conviene saber que, si alguna vez necesita un reemplazo total invertido del hombro (un tipo de prótesis en el que se invierten las posiciones de la esfera y la cavidad), aproximadamente 1 de cada 4 personas experimenta sensibilidad local en el área del os acromiale tras la intervención. En la mayoría de esos casos, el malestar desaparece por sí solo con el tiempo. Además, la presencia de un os acromiale no parece afectar negativamente los resultados de dicha cirugía.

La cirugía no es adecuada para todos, ni siempre es la mejor opción para los atletas. Algunos hombros con fragmentos no fusionados y problemas en el manguito rotador responden peor a la cirugía que otros; por eso su cirujano evaluará cuidadosamente esta situación junto con usted antes de recomendar cualquier tratamiento.

En resumen: si se deja sin tratar, un fragmento óseo doloroso puede seguir provocando molestias cada vez que levante el brazo por encima de la cabeza. Con un manejo adecuado, la mayoría de las personas logran alivio, ya sea mediante tratamientos no quirúrgicos o mediante cirugía cuando es necesario. Su cirujano le explicará cuál es el mejor camino según su hombro, sus actividades y sus objetivos.

¿Cuándo consultar a un especialista?

Acuda a su médico de cabecera si presenta dolor en la parte frontal y lateral de la parte superior del hombro que no mejora, especialmente si empeora al levantar el brazo por encima de la cabeza. Solicite una evaluación especializada si esa zona es sensible al tacto, si siente debilidad en el hombro o si le resulta más difícil levantar el brazo hacia adelante. Lo mismo aplica si el reposo, el cambio de actividades o una inyección de esteroides no han surtido efecto, o si el dolor comenzó tras un golpe o caída sobre ese hombro. Los nadadores y atletas que lanzan objetos y padecen dolor de hombro que no mejora con fisioterapia también deberían informarse sobre esta afección. En la mayoría de los casos, los fragmentos óseos que no se han fusionado nunca causan problemas; por lo tanto, el diagnóstico no implica que se necesite tratamiento urgente.

En mayor profundidad

Esta sección profundiza más de lo necesario para que usted tome sus propias decisiones de tratamiento. El acromion accesorio merece ser leído con atención, ya que constituye una variante anatómica normal en una proporción significativa de personas; por lo general no provoca ningún problema y, con frecuencia, se le atribuye el dolor en el hombro cuando en realidad no es la causa.

¿Qué es y qué frecuencia tiene?

El acromion, la estructura ósea que forma el techo de la articulación del hombro, se forma a partir de varios centros óseos que normalmente se fusionan a finales de la adolescencia o al inicio de la edad adulta. En algunas personas, uno de esos centros no se fusiona, dejando una unión fibrosa permanente. Eso es lo que se conoce como “os acromiale”, y está presente desde la adolescencia, no se adquiere posteriormente.

La prevalencia varía según la población. Un estudio multicéntrico realizado en 6,842 pacientes determinó que el os acromiale está asociado a lesiones del manguito rotador; además, su prevalencia en la población japonesa estudiada fue menor que en poblaciones no asiáticas, y el tamaño del fragmento tendía a ser más pequeño [1].

Esta asociación con las lesiones del manguito rotador merece ser analizada con detenimiento. Demuestra que ambos fenómenos ocurren juntos con mayor frecuencia de lo que cabría esperar por azar, pero no que el os acromiale cause la rotura del manguito. El mecanismo probable funciona en ambos sentidos: el fragmento no fusionado se mueve ligeramente bajo la acción del músculo deltoides, lo cual podría irritar el tendón subyacente; o bien, la misma mecánica articular que predispone a las lesiones del manguito rotador hace que el fragmento inestable genere síntomas.

La gran incógnita es si realmente es la causa del dolor

Dado que es visible, permanece en el lugar y presenta un aspecto anormal en las imágenes, el hueso acromial suele ser señalado como la causa del dolor en el hombro. Sin embargo, la mayoría de ellos no causan síntomas; de hecho, la mayor parte de las personas que lo tienen ni siquiera lo saben.

Lo que diferencia a los casos sintomáticos es la sensibilidad localizada directamente sobre el fragmento óseo, el dolor que se reproduce al presionarlo y, cuando se realiza una inyección diagnóstica, el alivio que se obtiene al inyectar precisamente en esa zona de unión y no en el espacio subacromial situado debajo. Si no se presentan estos signos, lo más adecuado es considerar este hallazgo como algo incidental.

Los subtipos se clasifican habitualmente según el sitio de fusión afectado [2]; esto es relevante desde el punto de vista quirúrgico, pues el tamaño del fragmento móvil determina si puede extirparse o si es necesario fijarlo.

Por qué complica otras cirugías de hombro

La importancia práctica del os acromiale radica menos en sus propios síntomas que en el efecto que tiene sobre las intervenciones quirúrgicas programadas para otras patologías.

El deltoides se inserta en el acromion; por ello, un fragmento no fusionado queda sometido a esa tracción en una zona anatómica móvil. Al extraer hueso de su superficie inferior, como se hace en la acromioplastia, se reduce aún más el grosor de un fragmento ya de por sí inestable, lo que puede transformar una variante asintomática en una condición dolorosa o provocar una no unión. Este es el motivo principal por el cual debe identificarse mediante estudios de imagen preoperatorios: no para tratarlo, sino para evitar desestabilizarlo.

Cuando sí es necesario tratarlo, se debe optar entre extirpar un fragmento pequeño o fijar uno más grande. La fijación en esta zona resulta difícil: el fragmento es delgado, el deltoides ejerce una tracción constante sobre él y las tasas de no unión son considerables. Esta dificultad constituye, en sí misma, una razón para confirmar que el os acromiale es realmente la causa del dolor antes de proceder a cualquier intervención quirúrgica.

Referencias

[1] Kozono N, Nishii A, Ishitani E, Mizuki Y, Kimura T, Yamamoto S, et al. Prevalencia y factores asociados al os acromiale: un estudio multicéntrico. JSES Int. 2025;9(5):1541-5. https://doi.org/10.1016/j.jseint.2025.05.015

[2] Boehm TD, Matzer M, Brazda D, Gohlke FE. Tratamiento quirúrgico del os acromiale asociado a desgarro del manguito rotador. Revisión de 33 pacientes. J Bone Joint Surg Br. 2003;85(4):545-9. https://doi.org/10.1302/0301-620X.85B4.13634


Evidence & references

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview

  • In Thai patients with shoulder problems who required MRI evaluation, the prevalence of os acromiale was 2.13% [1].
  • Os acromiale is associated with rotator cuff injuries [5].
  • A multicenter study determined the prevalence of and factors associated with os acromiale in the Japanese population [6].
  • Surgical treatment is usually not indicated for os acromiale in the professional tennis player [7].
  • The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after surgery, and reverse total shoulder arthroplasty remains a safe and effective treatment option [4].
  • The outcome of reverse total shoulder arthroplasty does not seem to be negatively affected by the presence of an os acromiale [9].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients but resolves spontaneously over time in the majority of patients [3].
  • Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate [13].
  • Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes [2].
  • Surgical options for symptomatic os acromiale include arthroscopic sub-total excision, arthroscopic subacromial decompression of stable fragments, and open reduction and internal fixation of unstable fragments [10].

Anatomy & Pathophysiology

Bony Anatomy

  • The acromion has three ossification centers: the metacromion (base), the mesoacromion (middle), and the preacromion (tip) [28].
  • Failure of fusion of the acromial ossification centers results in os acromiale [28].
  • The unfused segment in os acromiale is most commonly the meso-acromion, a configuration often termed a meso-type os acromiale [14].
  • The scapula is attached to the axial skeleton by the clavicle, specifically via the acromioclavicular (AC) and sternoclavicular (SC) joints [27].
  • The acromion is a flattened bony process that curves forwards from the scapular spine [27].
  • The acromion, coracoacromial ligament, and coracoid process form the coracoacromial arch, a rigid bony-ligamentous structure that imparts stability to the shoulder girdle [25].
  • The rotator cuff, subacromial bursa, and subdeltoid bursa pass underneath the coracoacromial arch [25].

Pathophysiology

  • Most diagnoses of os acromiale are made incidentally on axillary view radiographs of the shoulder [14].
  • Primary shoulder pain is usually unrelated to the unfused os acromiale [14].
  • When os acromiale drives symptoms, the two principal causes are motion at the non-union site or an impingement-type syndrome resulting from flexion of the os fragment during deltoid contraction and arm elevation [14].
  • Pain from os acromiale via these mechanisms has been reported in a variety of sports, particularly among throwing athletes and swimmers [14].
  • Previously stable non-unions can become unstable following an episode of blunt trauma to the region, such as direct impact to the shoulder during American football [14].
  • A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site [8].
  • Extrinsic impingement occurs when the space available for the rotator cuff is diminished, with examples including subacromial spurring, acromial fracture, or pathologic os acromiale [37].
  • The synchondrosis of an os acromiale can be injured following trauma, though rarely [15].
  • The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after reverse total shoulder arthroplasty (rTSA) [4].
  • The outcome of reverse total shoulder arthroplasty (RTSA) does not seem to be negatively affected by the presence of an os acromiale [9].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients following reverse total shoulder arthroplasty but resolves spontaneously over time in the majority of patients [3].

Classification

  • Meta–os acromiale is the rarest subtype of os acromiale [18].
  • Meso-type os acromiale is a recognized classification variant for which biomechanical evaluation of internal fixation has been performed [23].

Clinical Presentation

  • Liberson reviewed 1800 shoulder girdles and identified an incidence of os acromiale of 1.4% [16].
  • In Liberson's review of 1800 shoulder girdles, the lesion was bilateral in 62% of patients [16].
  • The unfused segment in os acromiale is most commonly the meso-acromion [14].
  • Any primary shoulder pain is usually unrelated to the unfused os acromiale [14].
  • When os acromiale drives symptoms, one principle cause is motion at the non-union site [14].
  • When os acromiale drives symptoms, another principle cause is an impingement-type syndrome resulting from flexion of the os fragment during deltoid contraction and arm elevation [14].
  • Pain from os acromiale by the mechanism of impingement has been reported in a variety of sports, particularly among throwing athletes and swimmers [14].
  • Previously stable non-unions of os acromiale can become unstable following an episode of blunt trauma to the region [14].
  • Multicenter study findings support that os acromiale is associated with rotator cuff injuries [5].
  • Awareness of os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis [12].
  • Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients following reverse total shoulder arthroplasty [3].
  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients following reverse total shoulder arthroplasty [3].
  • The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after surgery and rTSA remains a safe and effective treatment option [4].
  • The outcome of RTSA does not seem to be negatively affected by the presence of an os acromiale [9].

Investigations

  • Liberson reviewed 1800 shoulder girdles and identified an incidence of os acromiale of 1.4%, with the lesion being bilateral in 62% of patients [16].
  • Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis [12].
  • The synchondrosis of an os acromiale can be injured following trauma, though rarely, and emphasizes the need for appropriate radiographic investigation including axillary views [15].
  • At least two X-ray views should be obtained: an anteroposterior in the plane of the glenoid and an axillary projection with the arm in abduction to show the relationship of the humeral head to the glenoid [33].
  • Magnetic resonance imaging (MRI) is useful to identify labral tears and rotator cuff tears, although the accuracy for these is enhanced by combining the scan with arthrography [33].
  • Ultrasound is a simple and accurate test for identifying rotator cuff tears and calcific tendinitis [33].
  • The purpose of imaging of the shoulder is to help establish the diagnosis, determine the severity of the pathoanatomy, assist in surgical planning, and enable the surgeon to illustrate the condition of the shoulder to the patient [21].
  • Unless a specific research protocol is in place, the temptation to “overimage” should be resisted, obtaining only the scans or reconstructions that are necessary for the care of the patient [21].
  • Standardized plain films are almost always sufficient to garner the information needed, and there is information that can be gathered from properly taken plain films that cannot be obtained from CT scans [21].
  • The first key view is the anteroposterior (AP) in the plane of the scapula taken so that the x-ray beam passes through the glenohumeral joint [21].
  • The second key view is the axillary view taken with the arm in the functional position of elevation in the plane of the scapula and oriented so that both the spinoglenoid notch and the scapular neck are visible [21].
  • The axillary view is referred to as the “truth view” because it demonstrates the glenohumeral relationships in the functional position of elevation [21].
  • CT scans have the disadvantage of being taken with the arm in the adducted position, whereas the axillary truth view is taken with the arm in elevation [21].
  • A robust approach to imaging the shoulder needs to recognize that the shoulder is a three-dimensional structure that cannot be represented by a single planar view [35].
  • Critical relationships—such as the degree of centering of the humeral head—change with the position of the arm [35].
  • Shoulder pathology may be found in a large number of different bones and soft tissues [35].
  • Overlying and superimposed structures as well as metallic implants may complicate imaging the structures of interest [35].
  • Surgeons need to develop a judicious approach that yields the information necessary to treat the patient while avoiding the tendency to "over-image" [35].

Treatment

Non-Operative

  • Any primary shoulder pain is usually unrelated to the unfused os [14].
  • Conservative treatment for symptomatic os acromiale can include physical therapy with ice and infiltration of the os acromial joint with Kenacort and Xylocaine 2% [40].

Operative

  • Meta–os acromiale is the rarest subtype of os acromiale, and special consideration must be given to the type of tension-band construct used to achieve adequate compression and fixation [18].
  • Arthroscopic fixation of os acromiale with absorbable screws provides promising clinical, cosmetic, and radiologic results with high patient satisfaction [22].
  • A symptomatic os acromiale in a competitive female fastball pitcher was treated successfully with open reduction and internal fixation [41].
  • For symptomatic os acromiale treated with osteosynthesis, nine screws (2.7- and 3.5-mm) were used in one case, including six anterior angle-stable screws, two posterior cortical screws, and two angle-stable locking screws [40].
  • In cases of congenital or primary pseudarthrosis of os acromiale treated with osteosynthesis, an osteotomy of 1 mm was performed on each side of the osseous non-union including the cranial osteophytes [40].

Complications

  • Postoperative local tenderness at the os acromiale resolves spontaneously over time in the majority of patients [3].
  • Previously stable non-unions of the os acromiale can become unstable following an episode of blunt trauma to the region [14].

Key Evidence

  • [L3] In Thai patients with shoulder problems who required MRI evaluation, the prevalence of os acromiale was 2.13%. [1] (10.1177/23259671221078806)
  • [L4] Operative management of a symptomatic os acromiale that has failed initial nonoperative treatment leads to decreased symptoms and improvement in clinical outcomes. [2] (10.1016/j.jse.2019.05.047)
  • [L3] Postoperative local tenderness at the os acromiale can be expected in 1 out of 4 patients but resolves spontaneously over time in the majority of patients. [3] (10.1177/2325967120965131)
  • [L4] The presence of os acromiale does not appear to have a negative impact on the clinical outcomes after surgery and rTSA remains a safe and effective treatment option. [4] (10.1016/j.xrrt.2025.01.002)
  • [L3] The study supports previous findings that os acromiale is associated with rotator cuff injuries. [5] (10.1016/j.jseint.2025.05.015)
  • [L3] This multicenter study aimed to determine the prevalence of and factors associated with os acromiale in the Japanese population. [6] (10.1016/j.jse.2025.01.008)
  • [L4] Surgical treatment is usually not indicated for os acromiale in the professional tennis player. [7] (10.1177/2325967118773723)
  • [L4] A tear of the rotator cuff may often be associated with os acromiale, likely due to impingement from abnormal motion at the fibrous union site. [8] (10.2106/00004623-198466080-00029)
  • [L4] The outcome of RTSA does not seem to be negatively affected by the presence of an os acromiale. [9] (10.1016/j.jse.2017.02.012)
  • [L5] Surgical options for symptomatic os acromiale include arthroscopic sub-total excision, arthroscopic subacromial decompression of stable fragments, and open reduction and internal fixation of unstable fragments. [10] (10.5435/jaaos-d-17-00011)
  • [L4] Awareness of the os acromiale in the young athlete, appropriate clinical examination, and image studies are crucial to confirm diagnosis. [12] (10.1016/j.jseint.2020.02.008)
  • [L4] Ipsilateral os acromiale may be a relative contraindication to the clavicle hook plate. [13] (10.1186/s12891-021-04841-1)
  • [L4] [14] (10.1302/2058-5241.4.180100)
  • [L4] This case highlights that the synchondrosis of an os acromiale can be injured following trauma, though rarely, and emphasizes the need for appropriate radiographic investigation including axillary views and a flexible surgical approach. [15] (10.1016/j.jse.2008.02.012)
  • [L4] Meta–os acromiale is the rarest subtype of os acromiale, and special consideration must be given to the type of tension-band construct used to achieve adequate compression and fixation. [18] (10.1177/03635465211028238)
  • [L4] This new arthroscopic technique of fixation of os acromiale with absorbable screws provides promising clinical, cosmetic, and radiologic results with high patient satisfaction. [22] (10.1016/j.jse.2011.12.011)
  • [L5] Surgical repair of a simulated, unstable meso-type os acromiale by a combination of cannulated screws inserted in the A-P direction with a tension band leads to significantly improved repair strength at time zero compared with cannulated screws alone. [23] (10.1016/j.jse.2014.09.040)
  • [L4] [40] (10.1186/s40634-017-0111-7)
  • [L4] A symptomatic os acromiale in a competitive female fastball pitcher was treated successfully with open reduction and internal fixation. [41] (10.1177/0363546506288305)

References

[1] Prevalence of Os Acromiale in Thai Patients With Shoulder Problems: A Magnetic Resonance Imaging Study. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/23259671221078806

[2] Os acromiale: systematic review of surgical outcomes. Journal of Shoulder and Elbow Surgery. 2020. DOI: 10.1016/j.jse.2019.05.047

[3] Os Acromiale in Reverse Total Shoulder Arthroplasty: A Cohort Study. Orthopaedic Journal of Sports Medicine. 2020. DOI: 10.1177/2325967120965131

[4] Clinical implications of reverse total shoulder arthroplasty with an os acromiale: a systematic review. JSES Reviews, Reports, and Techniques. 2025. DOI: 10.1016/j.xrrt.2025.01.002

[5] Prevalence and factors associated with os acromiale: a multicenter study. JSES International. 2025. DOI: 10.1016/j.jseint.2025.05.015

[6] The prevalence and associated factors of os acromiale: a multicenter study. Journal of Shoulder and Elbow Surgery. 2025. DOI: 10.1016/j.jse.2025.01.008

[7] Os Acromiale in Professional Tennis Players. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967118773723

[8] Rotator cuff tears associated with os acromiale.. The Journal of Bone & Joint Surgery. 1984. DOI: 10.2106/00004623-198466080-00029

[9] Reverse shoulder arthroplasty in patients with os acromiale. Journal of Shoulder and Elbow Surgery. 2017. DOI: 10.1016/j.jse.2017.02.012

[10] Symptomatic, Unstable Os Acromiale. Journal of the American Academy of Orthopaedic Surgeons. 2018. DOI: 10.5435/jaaos-d-17-00011

[12] The unstable os acromiale: a cause of pain in the young athlete. JSES International. 2020. DOI: 10.1016/j.jseint.2020.02.008

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[14] Os acromiale: a review of its incidence, pathophysiology, and clinical management. EFORT Open Reviews. 2019. DOI: 10.1302/2058-5241.4.180100

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