Radiographic Signs of Osseointegration in Porous-coated Acetabular Components

107

Background Reconstruction of large acetabular defects remains a substantial challenge in hip arthroplasty. There remains a paucity of data on the long-term results of acetabular trabecular metal augments. Questions/purposes The purpose of this study was to assess the survivorship, clinical outcomes, restoration of center of rotation of the hip, and radiological signs of component fixation of trabecular metal augments in the context of reconstruction of acetabular defects. Methods Between 2002 and 2005, we performed 56 revision (n = 53) and primary (n = 3) THAs using trabecular metal augments in combination with a trabecular metal acetabular component. Of the 56 patients, 16 (29%) died during followup. Of the 40 surviving patients, 37 (93%) had complete radiological followup, 23 (58%) had complete outcome questionnaire followup, and 17 (42%) provided partial questionnaire responses in the clinic or over the telephone. Median followup was 110 months (range, 88-128 months). During that period, we used these implants when preoperative templating indicated that an augment would be required to achieve acetabular implant stability with restoration of the hip center of rotation. We also chose during surgery to use an augment when we could not achieve a stable acetabular trial component without one. The combination of trabecular metal augments and trabecular metal shells was used in 18% (53 of 292) of our acetabular revisions during that time. Survivorship, functional outcome (WOMAC and Oxford hip score), health status (SF-12), and osseointegration according to the criteria of Moore and presence of radiolucencies were determined.

Section: Discussionmentioning

confidence: 75%

Section: Methodsmentioning

confidence: 99%

Continued Good Results With Modular Trabecular Metal Augments for Acetabular Defects in Hip Arthroplasty at 7 to 11 Years

Whitehouse

Masri

Duncan

et al. 2015

107

“…Radiographs were also evaluated for any periacetabular loosening judged by radiolucent lines around the border of the acetabulum or any migration defined as medial displacement with respect to the ilioischial line compared with previous radiographs. We further used the five criteria established by Moore et al [14] for osseointegration. Cups demonstrating at least one, two, or three of five criteria were considered to be osseointegrated.…”

Section: Methodsmentioning

confidence: 99%

Does a Titanium-coated Polyethylene Press-fit Cup Give Reliable Midterm Results?

Hooper

Sargeant

Frampton

et al. 2015

Background Uncemented acetabular components have demonstrated low revision rates and high patient satisfaction but with concerns regarding increased costs compared with monoblock cups. Some newer lower-cost uncemented monoblock options have become available in the last decade, but limited data are available on their performance. Questions/purposes (1) Does an uncemented, titaniumbacked all-polyethylene acetabular cup provide reliable fixation? (2) What is the frequency and what are the causes for revision with this cup?Methods Between 2004 and 2008, we elected to use an uncemented, titanium-backed all-polyethylene acetabular cup in older patients with limited physical demands. We performed 615 hip replacements in 550 patients with greater than 5 years of clinical and radiographic followup. When patients who were dead (80 hips in 75 patients), lost to followup (98 hips in 93 patients), or revised (three hips in three patients) were excluded, there were 434 hips in 379 patients for comparison of the postoperative and 5-year radiographs. Two observers not involved in the index surgical procedures (NH, HS) assessed radiographs for signs of migration or loosening. Some degree of early movement sometimes is seen before cup stabilization; however, to be conservative, we defined cups with greater than 3°of change of position (even if they subsequently stabilized) as potentially at risk and report them separately. Revision surgery, time from the index procedure, and the reason for revision were recorded from the New Zealand Joint Registry. Results By 5 years there was a median change in inclination of 2°(range, 0°-13°; 95% confidence interval [CI], 2.0-2.4; p \ 0.001) and 2°of anteversion (range, 0°-11°; 95% CI, 2.0-2.4; p \ 0.001). Although at last followup all cups appeared to have stabilized with no radiolucent lines or medial migration, 22% of the cups (94 of 434) had moved more than 3°and so were deemed to be potentially at risk. There were 11 revision procedures (of 429 hips; 2.5%) of which six were for recurrent dislocation, four for femoral fracture, and one for femoral loosening to give an overall all-cause revision rate for all components of 0.25 per 100 component years (95% CI, 0.13-0.43). No revisions were performed for acetabular loosening. Conclusions The short-to medium-term results of this allpolyethylene monoblock cup demonstrated a low frequency of revision. However, 94 cups were identified as potentially

“…Subsequently based on the type of bone deficiency, we divided the hips into two groups: minor including Paprosky 1, 2A and 2B, and major including Paprosky 2C, 3A and 3B. We (SMJ and BB) used the three acetabular zones of DeLee-Charnley model and the Anderson Orthopaedic Research Institute radiographic criteria to assess radiographic bone ingrowth [5,17]. We conducted a power analysis.…”

Section: Methodsmentioning

confidence: 99%

Do Tantalum and Titanium Cups Show Similar Results in Revision Hip Arthroplasty?

Jafari

Bender

Coyle

et al. 2010

Porous surfaces are intended to enhance osteointegration of cementless implants. Tantalum has been introduced in an effort to enhance osseointegration potential of uncemented components. We therefore compared the clinical outcome of acetabular components with two different porous surfaces. We retrospectively reviewed 283 patients (295 hips) who underwent cementless revision hip arthroplasty with either an HA-coated titanium cup (207 patients, 214 hips) or porous tantalum cup (79 patients, 81 hips). The minimum followup was 24 months in both groups (titanium: average 51.8 months, range, 24-98 months; tantalum: average, 35.4 months, range, 24-63 months). The titanium and tantalum groups had a mechanical failure rate (clinical plus radiographic) of 8% and 6%, respectively. In hips with minor bone deficiency (type 1, 2A, 2B using the classification of Paprosky et al.), 6% of titanium cups and 4% of tantalum cups failed. In hips with major bone deficiency (type 2C, 3), 24% of titanium cups and 12% of tantalum cups developed failure. In the major bone deficiency group, the tantalum cups had fewer numbers of lucent zones around the cup. Eighty-two percent of titanium cups that failed did so at 6 months postoperatively or later, whereas 80% of tantalum cups that failed did so in less than 6 months. Radiographically in the major group, tantalum cups yielded better fixation.