Dataset Information

Acetabular cup position and risk of dislocation in primary total hip arthroplasty.

ABSTRACT: Background and purpose - Hip dislocation is one of the most common complications following total hip arthroplasty (THA). Several factors that affect dislocation have been identified, including acetabular cup positioning. Optimal values for cup inclination and anteversion are debatable. We performed a systematic review to describe the different methods for measuring cup placement, target zones for cup positioning, and the association between cup positioning and dislocation following primary THA. Methods - A systematic search of literature in the PubMed database was performed (January and February 2016) to identify articles that compared acetabular cup positioning and the risk of dislocation. Surgical approach and methods for measurement of cup angles were also considered. Results - 28 articles were determined to be relevant to our research question. Some articles demonstrated that cup positioning influenced postoperative dislocation whereas others did not. The majority of articles could not identify a statistically significant difference between dislocating and non-dislocating THA with regard to mean angles of cup anteversion and inclination. Most of the articles that assessed cup placement within the Lewinnek safe zone did not show a statistically significant reduction in dislocation rate. Alternative target ranges have been proposed by several authors. Interpretation - The Lewinnek safe zone could not be justified. It is difficult to draw broad conclusions regarding a definitive target zone for cup positioning in THA, due to variability between studies and the likely multifactorial nature of THA dislocation. Future studies comparing cup positioning and dislocation rate should investigate surgical approach separately. Standardized tools for measurement of cup positioning should be implemented to allow comparison between studies.

SUBMITTER: Seagrave KG

PROVIDER: S-EPMC5251254 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Acetabular cup position and risk of dislocation in primary total hip arthroplasty.

Seagrave Kurt G KG Troelsen Anders A Malchau Henrik H Husted Henrik H Gromov Kirill K

Acta orthopaedica 20161123 1

Background and purpose - Hip dislocation is one of the most common complications following total hip arthroplasty (THA). Several factors that affect dislocation have been identified, including acetabular cup positioning. Optimal values for cup inclination and anteversion are debatable. We performed a systematic review to describe the different methods for measuring cup placement, target zones for cup positioning, and the association between cup positioning and dislocation following primary THA. ...[more]

PMID: 27879150

Similar Datasets

Project description:The concept of a dual mobility (DM) cup has been in existence for more than 40 years and was initially popularized in Europe. Only recently has it started to garner attention in the United States. Its design, consisting of a small femoral head articulating within a larger polyethylene (PE) insert, which articulates with an outer shell, has found increasing use in patients that are at risk for post-operative dislocations. This case report describes a case of recurrent total hip arthroplasty (THA) dislocation managed with the implantation of a DM cup with an acute intraprosthetic dislocation of the DM construct.A 52-year-old woman underwent an uneventful left THA through a posterior approach. Within 6 weeks of her surgery, she had four dislocations, managed with closed reductions. She then underwent an open revision of her acetabular component with conversion to a DM construct. 5 weeks after her revision, she had another dislocation treated with closed reduction in the operating room, with the resultant eccentric location of the femoral head in the acetabular component. Computed tomography (CT) confirmed intraprosthetic dislocation with the PE liner lodged in the gluteal tissue. She was taken to the operating room with a plan to revise her acetabular component to another DM construct, but with an increase in the anteversion despite initial anteversion being "appropriate" on CT imaging. Intraoperatively, the PE liner was embedded in gluteal tissue as depicted on the CT. The abductors were intact. There was no impingement in extension and maximal external rotation when trialed with a conventional head/liner construct. A new DM construct was then implanted.Intraprosthetic dislocation is a rare occurrence and unique complication to DM constructs. It is not common in the short-term setting postoperatively to our knowledge, and this case report represents an early report of intraprosthetic dislocation in the literature. Care should be taken during reduction of dislocated DM constructs to avoid intraprosthetic dislocations. Open revisions can be managed with revisions to another DM construct or to a constrained liner construct to maximize stability.

Project description:BackgroundMany risk factors have been described for dislocation following total hip arthroplasty (THA), yet a patient-specific risk assessment tool remains elusive. The purpose of this study was to develop a high-dimensional, patient-specific risk-stratification nomogram that allows dynamic risk modification based on operative decisions.MethodsIn this study, 29,349 THAs, including 21,978 primary and 7371 revision cases, performed between 1998 and 2018 were evaluated. During a mean 6-year follow-up, 1521 THAs were followed by a dislocation. Patients were characterized, through individual-chart review, according to non-modifiable factors (demographics, indication for THA, spine disease, prior spine surgery, and neurologic disease) and modifiable operative decisions (operative approach, femoral head diameter, and type of acetabular liner [standard, elevated, constrained, or dual-mobility]). Multivariable regression models and nomograms were developed with dislocation as a binary outcome at 1 year and 5 years postoperatively.ResultsDislocation risk, based on patient-specific comorbidities and operative decisions, was wide-ranging-from 0.3% to 13% at 1 year and from 0.4% to 19% at 5 years after primary THA, and from 2% to 32% at 1 year and from 3% to 42% at 5 years after revision THA. In the primary-THA group, the direct anterior approach (hazard ratio [HR] = 0.27) and lateral approach (HR = 0.58) decreased the dislocation risk compared with the posterior approach. After adjusting for the approach in that group, the combination of a ≥36-mm-diameter femoral head and an elevated liner yielded the largest decrease in dislocation risk (HR = 0.28), followed by dual-mobility constructs (HR = 0.48). In the patients who underwent revision THA, the adjusted risk of dislocation was most markedly decreased by the use of a dual-mobility construct (HR = 0.40), followed by a ≥36-mm femoral head and an elevated liner (HR = 0.88). The adjusted risk of dislocation after revision THA was decreased by acetabular revision (HR = 0.58), irrespective of whether other components were revised.ConclusionsOur patient-specific dislocation risk calculator, which was strengthened by our use of a robust multivariable model that accounted for comorbidities associated with instability, demonstrated wide-ranging patient-specific risks based on comorbidity profiles. The resultant nomograms can be used as a screening tool to identify patients at high risk for dislocation following THA and to individualize operative decisions for evidence-based risk mitigation.Level of evidencePrognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Dataset Information

Acetabular cup position and risk of dislocation in primary total hip arthroplasty.

Publications

Acetabular cup position and risk of dislocation in primary total hip arthroplasty.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets