Clinical results and complications following surgical management of symptomatic os acromiale: a systematic review

Arthroscopic Fixation of Symptomatic Meso-Type Os Acromiale: Technical Note

Symptomatic Os acromiale can cause pain, impingement, and reduced range of movement. Disruption of the syndesmosis can result in significant pain and functional impairment; this may occur after trauma. Symptomatic Os acromiale is treated by either excision or fixation. Fixation via open technique is the mainstay of surgical intervention; however, recently, arthroscopic methods were used. In this technical note, we discuss the modification for all arthroscopic Os acromiale fixation; the fixation screws are introduced in anteroposterior fashion, employing the advances in orthopaedic fixation devices. Arthroscopic fixation is not widely adopted, possibly due to availability of implants and perceived difficult learning curve. We report this technique and demonstrate reproducibility with excellent results.

Os acromiale: prevalence and associated patient-related factors-a population-based study of three thousand and fifty participants

Purpose

The presence of os acromiale is of clinical relevance before performing shoulder surgery but ethnic differences and little information regarding associated factors seem to be present. Population-based studies to clarify these topics are essential so the purpose of this study was to assess the prevalence, anatomy, and associations of os acromiale in a general adult population.

Methods

Both shoulders of 3050 participants from the population-based Study of Health in Pomerania (SHIP) were assessed on magnetic resonance imaging (MRI). Associations with the os acromiale were calculated for sex, age, body height, body weight, and heavy mechanical oscillations on the upper extremity.

Results

In total, 1.9% (58/3050) had an os acromiale, while 21 were unilateral left, 23 were unilateral right, and 14 were bilateral. Sixty-eight meso-acromions, three pre-acromions, and one meta-acromion were detected. Os acromiale were more frequent in men (right side: p = 0.037, left side: p = 0.005). Overall, no differences in sides (p = 0.808), to participants’ age (right: p = 0.993, left: p = 0.499), body height (right side: p = 0.241, left side: p = 0.154), and the exposure to heavy mechanical oscillations on the upper extremity (right: p = 0.054, left: p = 0.117) were detected.

Conclusion

Our results support the genetic theory for the aetiology of the os acromiale due to the lower prevalence of the os acromiale in north-eastern Germany compared to the worldwide prevalence (1.9 to 7%) and the lacking association to lifestyle, age, gender, or sides. Additionally, it is important to be aware of possible os acromiale before surgery.

Arthroscopic "Wallow" Procedure for Resection of Symptomatic Os Acromiale Pseudoarthrosis

Os acromiale is a relatively common anatomic variant that can occasionally be associated with shoulder pain. Several surgical options to address a symptomatic os acromiale that has failed nonoperative treatment have been described. Published techniques, however, are often very invasive, technically challenging, and carry the risk of potential complications that can be difficult to manage. The technique presented here describes a relatively simple arthroscopic alternative, coined by the authors as the "Wallow technique" due to the fact that the arthroscopic shaver is used to rotate within and resect the os site, that results in complete resection of the os acromiale pseudoarthrosis and avoids the need for an open approach or the use of implants.

Reverse shoulder arthroplasty with os acromiale

Function and strength of the deltoid muscle are important in reverse shoulder arthroplasty (RSA). Moreover, location and shape of the acromion, clavicle, and scapular spine, which are origins of the deltoid muscle, are also important. The frequency of os acromiale is 5% to 15%; however, it is rare in the Asian population, affecting approximately 0.7% of Koreans. RSA has rarely been reported in patients with os acromiale. We present a case series of two patients with cuff tear and arthropathy combined with os acromiale who underwent RSA. From 2016 to 2018, two patients with os acromiale who presented with pain and limited range of motion (ROM) underwent RSA with cuff tear arthropathy using the subscapularis-sparing deltopectoral approach. Their ROM, visual analog scale (VAS), and satisfaction were evaluated before and after surgery. In both patients, VAS decreased, ROM increased, and postoperative satisfaction increased. There were no specific complications due to os acromiale. The VAS, ROM, and satisfaction of patients improved after surgery compared with values before surgery. However, careful attention must be given during surgery to ensure optimal repair and recovery.