Does cup-cage reconstruction with oversized cups provide initial stability in THA for osteoporotic acetabular fractures?

dc.contributor.authorSolomon, L.B.
dc.contributor.authorStuder, P.
dc.contributor.authorAbrahams, J.M.
dc.contributor.authorCallary, S.A.
dc.contributor.authorMoran, C.R.
dc.contributor.authorStamenkov, R.B.
dc.contributor.authorHowie, D.W.
dc.contributor.conferenceSymposium of the International Hip Society (20 Nov 2014 - 21 Nov 2014 : Rio de Janeiro, Brazil)
dc.date.issued2015
dc.description.abstractBackground The incidence of acetabular fractures in osteoporotic patients is increasing. Immediate total hip arthroplasty (THA) has potential advantages, but achieving acetabular component stability is challenging and, at early followup, reported revision rates for loosening are high. Questions/purposes This study measured acetabular component stability and the initial surface contact achieved between the acetabular component and unfractured region of the pelvis after THA using an oversized acetabular component and cup-cage reconstruction. Methods Between November 2011 and November 2013, we treated 40 acute acetabular fractures in patients older than 70 years of age. Of these, 12 (30%) underwent immediate THA using an oversized acetabular component with screws inserted only into the ilium and a cup-cage construct. Postoperatively all patients were mobilized without weightbearing restrictions. Indications for immediate THA after acetabular fractures were displaced articular comminution deemed unreducible. Eleven of the 12 were prospectively studied to evaluate the initial stability of the reconstructions using radiostereometric analysis. One of the patients died of a pulmonary embolism after surgery, and the remaining 10 (median age, 81 years; range, 72–86 years) were studied. Of these, five were analyzed at 1 year and five were analyzed at 2 years. Acetabular component migration was defined as acceptable if less than the limits for primary THA that predict later loosening (1.76 mm of proximal migration and 2.53 of sagittal rotation). The contact surface between the acetabular component and ilium in direct continuity with the sacroiliac joint, and the ischium and pubis in direct continuity with the symphysis pubis, was measured on postoperative CT scans. Results At 1 year the median proximal migration was 0.83 mm (range, 0.09–5.13 mm) and sagittal rotation was 1.3° (range, 0.1°–7.4°). Three of the 10 components had migration above the suggested limits for primary THA at 1 year postoperatively. The contact surface achieved at surgery between the acetabular component and pelvis ranged from 11 to 17 cm2 (15%–27% of each component). Conclusions The majority of acetabular components in this cohort were stable despite the small contact surface achieved between the component and pelvic bone. Three of 10 migrated in excess of the limits that predict later loosening in primary THA but it remains to be seen whether these limits apply to this selected group of frail osteoporotic patients. We continue to use this technique routinely to treat patients with the same indications, but since the analysis of these data we have added screw fixation of the acetabular component to the ischial tuberosity and the superior pubic ramus. Level of Evidence Level IV, therapeutic study.
dc.description.statementofresponsibilityLucian B. Solomon, Patrick Studer, John M. Abrahams, Stuart A. Callary, Caroline R. Moran, Roumen B. Stamenkov, Donald W. Howie
dc.identifier.citationClinical Orthopaedics and Related Research, 2015, vol.473, iss.12, pp.3811-3819
dc.identifier.doi10.1007/s11999-015-4460-1
dc.identifier.issn0009-921X
dc.identifier.issn1528-1132
dc.identifier.orcidSolomon, L.B. [0000-0001-6254-2372]
dc.identifier.orcidCallary, S.A. [0000-0002-2892-5238]
dc.identifier.orcidHowie, D.W. [0000-0003-1702-3279]
dc.identifier.urihttp://hdl.handle.net/2440/131168
dc.language.isoen
dc.publisherLIPPINCOTT WILLIAMS & WILKINS
dc.rights© The Association of Bone and Joint Surgeons® 2015
dc.source.urihttps://www.ncbi.nlm.nih.gov/pubmed/26194560
dc.subjectAcetabulum
dc.subjectHumans
dc.subjectJoint Instability
dc.subjectHip Fractures
dc.subjectProsthesis Failure
dc.subjectRadiography
dc.subjectTreatment Outcome
dc.subjectArthroplasty, Replacement, Hip
dc.subjectRisk Factors
dc.subjectProspective Studies
dc.subjectProsthesis Design
dc.subjectHip Prosthesis
dc.subjectBone Density
dc.subjectTime Factors
dc.subjectAged
dc.subjectAged, 80 and over
dc.subjectFemale
dc.subjectMale
dc.subjectOsteoporotic Fractures
dc.subjectBiomechanical Phenomena
dc.titleDoes cup-cage reconstruction with oversized cups provide initial stability in THA for osteoporotic acetabular fractures?
dc.typeConference paper
pubs.publication-statusPublished

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