Os acetabuli-a new arthroscopic treatment option for the acetabular rim fracture

Current concepts in the diagnosis and management of Os Acetabuli

PURPOSE

The aim of this review is to appraise the current evidence on the epidemiology, pathophysiology, diagnosis and management of os acetabuli.

METHODS

A scoping review was conducted according to the Joanna Briggs Institute guidelines. A systematic search was performed on Medline (PubMed), Embase and Cochrane Library. Inclusion criteria comprised observational and interventional studies and review articles published in the English language that focused on patients with os acetabuli according to the PRISMA extension of scoping reviews checklist using the terms 'Os Acetabuli' or 'os acetabula' or 'acetabular ossicles'. A narrative synthesis of results was undertaken, and the included articles were divided into (i) definition, (ii) aetiology, (iii) diagnosis and imaging and (iv) management of os acetabuli.

RESULTS

107 articles were screened, with 22 meeting the eligibility criteria. A total of 8836 patients were considered, of which 604 had os acetabuli. The mean age was 32.8 years. The prevalence of os acetabuli ranged from 3.4 to 7.7%, with a higher prevalence in males compared to females. True os acetabuli was defined as an unfused secondary ossification centre along the acetabular rim. The aetiology of os acetabuli is thought to be secondary to acetabular dysplasia and/or femoroacetabular impingement. Standard of care for management of symptomatic os acetabuli is considered to be arthroscopic excision unless the excision results in acetabular undercoverage and/or instability, in which case, fixation is recommended.

CONCLUSIONS

Successful management of os acetabuli depends on understanding the pathology and treating the underlying cause rather than treating the os acetabuli in isolation. Future work needs to focus on establishing clear diagnostic criteria, consensus on definition and an evidence-based treatment algorithm.

Acetabular Rim Disorders: Epidemiology, Etiology, Management, and Outcomes

» Anatomic disorders of the acetabular rim are a common, correctable source of hip pain in younger patients.» Some common conditions of involving abnormal acetabular rim morphology include developmental dysplasia of the hip, pincer-type femoroacetabular impingement, acetabular protrusion, and acetabular retroversion.» Treatment option for these conditions were historically limited to open osteotomy and osteoplasty procedures; however, there is increasing use of arthroscopic intervention for these patients.» Arthroscopic intervention has demonstrated short-term success in a variety of focal acetabular rim disorders; however, further research is needed to determine the long-term outcomes of these procedures and their utility in more global pathology.

Arthroscopic Suture Fixation of Os Acetabuli With Absorbable Suture Anchors-A Double-Pulley Technique

Os acetabuli is a bone fragment with unknown origin and isolated at the acetabular rim that may be associated with cam-type femoroacetabular impingement. If this bone fragment is too large and threatens the stability of the hip joint after resection, fixation would be recommended. However, conventional rigid fixation with metal screws has some disadvantages. We describe an arthroscopic suture fixation of the Os acetabulum with absorbable anchors penetrating the bone fragment and secured by tying knots in a double-pulley fashion simultaneously. This technique provides a new feasible solution for the fixation of Os acetabuli, avoiding any metal implants and potential damage to the joint.