Acetabular Fixation Research Articles

Primary Cementless Acetabular Fixation at a Minimum of Twenty Years of Follow-up

The purpose of the present study was to analyze the longer-term results for a previously reported cohort of patients with cementless acetabular fixation and to compare the results with those for historical controls with cement fixation and a comparable follow-up period. One hundred and twenty consecutive nonselected total hip arthroplasties were performed in 108 patients with use of a cementless acetabular component. This series was evaluated at a minimum of twenty years of follow-up and was compared with 330 consecutive hip arthroplasties that had been performed by the same surgeon with use of cemented acetabular components and had been followed for a comparable period of time. Thirty-nine patients (forty-two hips) in the cementless fixation group were living at twenty years of follow-up. In the group of 120 hips with cementless acetabular fixation, twenty-two hips (18.3%) were revised during the follow-up period, but only one hip (0.8%) was revised because of loosening of the acetabular component, with no additional cup loosening since the previous report at thirteen to fifteen years of follow-up. In the group with cemented acetabular fixation with comparable follow-up, thirty-two hips (10%) were revised overall and eighteen hips (6%) were revised because of acetabular loosening. An additional twenty-five hips (8%) had acetabular cups that were loose on radiographs but had not undergone revision. At a minimum of twenty years of follow-up, cementless acetabular components provided superior long-term fixation compared with cemented components but the overall rates of acetabular revision for mechanical reasons were comparable.

Minimum ten-year follow-up of acetabular fracture fixation from the Irish tertiary referral centre

BackgroundSuccessful outcome from acetabular fracture fixation is multi-factorial. Long-term results are not frequently reported. Pooling such data from high output centres will help progress acetabular fixation. This paper presents the first ten-year data from the Irish tertiary referral centre. AimTo audit the radiographic and clinical outcome of all patients who had acetabular fracture fixation in the unit a minimum of ten years previously. MethodsPatients were identified from the unit database. Each patient was contacted and invited to attend the hospital for clinical and radiographic review. Clinical review consisted of examination and three separate scoring systems using both subjective and objective parameters. Radiographic review consisted of a standard AP pelvis and Judet views. ResultsForty-four patients were identified. Follow up of 68% was achieved. Total hip arthroplasty rate was 13.8%. Twenty percent of the remaining native hips had radiographic evidence of established arthritis. Sixty-three percent of functional outcome scores were classified as ‘good’ or ‘excellent’. Radiographic and functional data did not strongly correlate. The strongest correlating factor with poor functional outcome was concurrent injuries, particularly sciatic nerve injury. ConclusionsThese data support the role of operative intervention for acetabular fractures in a tertiary referral centre and allow better counselling of patients on prognosis.

Cementless Acetabular Fixation in Patients 50 Years and Younger at 10 to 18 Years of Follow-Up

The purpose of the study was to evaluate the 10- to 18-year follow-up of cementless acetabular fixation in patients 50 years and younger. We retrospectively reviewed a consecutive group of 118 patients (144 hips) in whom primary total hip arthroplasty had been performed by 2 surgeons using a cementless acetabular component. Two (1.4%) cementless acetabular components were revised because of aseptic loosening. Twenty-four hips (16.7%) were revised for any mechanical failure of the acetabular component mostly related to acetabular liner wear and osteolysis. The average linear wear rate was 0.19 mm per year, which was higher than our previous reports with cemented acetabular fixation. The fiber mesh ingrowth surface of the cementless acetabular component in this study was superior to cemented acetabular components in terms of fixation. However, the high rates of wear and osteolysis have led to poor overall acetabular component construct survivorship.

Revision total hip arthroplasty using a reconstruction cage device and a cemented dual mobility cup

The main causes of total hip arthroplasty (THA) revisions are loosening and instability. Dual mobility cups were introduced to prevent instability, but their behavior during revisions with acetabular reconstruction has not been assessed. Use of a dual mobility cup cemented in a acetabular reconstruction cage device limits the risk of instability and does not hinder the acetabular fixation during THA revisions. The objective of this study was to test this hypothesis on a retrospective series of 96 revisions. At a mean follow-up of 41 months (range, 1-101 months), we analyzed a continuous series of 96 revisions using a reconstruction device (70 Kerboull™ cross-plates, six Burch-Schneider™ antiprotrusio cages, 20 custom-fit Novae ARM™ cages associated in all cases with a Novae Stick dual mobility cup cemented into the cage). Fifteen patients died at a mean follow-up of 22 months (range, 1-66 months) and four patients were lost to follow-up at a mean follow-up of 16 months (range, 9-27 months). These were acetabular revisons involving major bone loss, with 62 stage III and 26 stage IV cases on the SOFCOT classification. Eighty-seven patients (87.5%) underwent structural bone allografting. The mean Merle d'Aubigné score increased from 9.6 ± 3.06 (range, 2-16) preoperatively to 15.5 ± 2.32 (range, 7-18) at the follow-up. Ten dislocations (10.4%) occurred, five of which were delayed over three months after the index procedure (5.2%), but there were no intraprosthetic dislocations. At the follow-up, the X-rays showed eight hardware failures, including one cross-plate fracture, one hook fracture, and one flange fracture. Analysis of the radiological position of the cup showed a mean lowering of 15.6mm and a 9.4mm lateralization compared to the preoperative position. One revision for aseptic loosening and another for septic loosening were performed. Taking all-cause acetabular component exchange as a criterion, the survival rate at 8 years was 95.6% (95% CI, 93.3-97.7%) and 99.3% (95% CI, 98.9-99.6%) if the endpoint was aseptic acetabular exchange. This study confirms the advantage of dual mobility cups during acetabular reconstruction cemented in antiprotrusio cages as a way to limit, without eliminating, the risk of dislocation. Therefore cemented fixation of dual mobility cups in cages appears to be a reliable short-term option.

Reply to the comments of Li et al. to the article: Posterior wall reconstruction using iliac crest strut graft in severely comminuted posterior acetabular wall fracture

We read your letter regarding our recently published article “Posterior wall reconstruction using iliac crest strut graft in severely comminuted posterior acetabular wall fracture” [1]. Posterior wall fractures are the most common acetabular fracture. Most posterior wall fractures are either comminuted or impacted. The soft tissues are frequently detached from the fragments at the time of injury or during the surgery. Primary osteosynthesis of such comminuted and/or impacted fractures involves elevation of the impacted fragments, reduction of the articular surface and filling the void with bone graft/bone graft substitute. The fragments are then buttressed with lag screws and reconstruction plate to support the elevated and comminuted fragments. However, gross comminution and displacement of the fragments along the margin and articular part of acetabulum (osteochondral fragments) makes the fixation difficult by this technique. The orientation of the fragments is also distorted and makes the surgeon frustrated to think of primary osteosynthesis. The main determinants of outcome after posterior acetabular wall fracture fixation are joint congruency and stability. Inability to maintain the congruency and stability will lead to arthritis sooner or later. It is difficult to achieve and maintain articular congruency and stability in severely comminuted wall fracture. In our report, we have described iliac crest strut graft fixation in severely comminuted posterior acetabular wall fracture. By this technique, the comminuted small fragments are excised, the joint is washed and the defect in the posterior wall is reconstructed with appropriately-matched iliac crest strut graft which is buttressed by lag screws and a reconstruction plate. This single piece of bone graft can better withstand axial force compared to multifragmentary posterior wall, even after buttressing with reconstruction plate. This is essential as the graft or bone fragments have to withstand axial loading immediately after surgery during the rehabilitation programme. Again, anatomical reduction of this single bone graft would be easier compared to multiple bone fragments.

Total Hip Arthroplasty With Shortening Osteotomy in Congenital Major Hip Dislocation Sequelae

We retrospectively evaluated the postoperative results of total hip arthroplasty (THA) in patients presenting with Crowe group IV dislocated hips. Overall, results were compared with regard to the type of osteotomy performed (Z or oblique) to define the correct indications for surgical technique and choice of prosthetic implant. Thirty-three subtrochanteric shortening and derotational osteotomies in primary THA were performed in 26 patients secondary to congenital hip dislocation. A Z osteotomy was performed in 14 cases and an oblique osteotomy in 19. The surgical approach was direct lateral, and surgery was aimed at restoring the anatomic hip center. Femoral and acetabular fixation was uncemented. The most used stem was the S-ROM (DePuy, Leeds, United Kingdom), and the couplings used were ceramic-ceramic (7 cases), ceramic-polyethylene (3 cases), metal-polyethylene (15 cases), and metal-metal (3 cases). Mean follow-up was 88±45 months. According to the Merle D'Aubigné score, the overall clinical results were good in 23 cases, satisfactory in 6, and fair in 4. Union of the osteotomy occurred in 97% of cases, and the mean time required for osteotomy union was 6±2 months without significant differences between Z and oblique osteotomies. At last follow-up, there was loosening of 1 cup and 1 stem, and revision was necessary. Twelve percent of patients experienced postoperative dislocation and 9% developed neuropraxia of the femoral nerve. The clinical and radiological results were similar in both groups, with a high rate of pain relief, an improvement in limb-length discrepancy, and reduced limping, leading to a smaller or no insole. Currently, the more complex Z osteotomy has been abandoned, because a modular stem prosthesis with metaphyseal sleeve allows the oblique osteotomy to be used with an easier and shorter surgical procedure.

Clinical report. Atypical acetabular bone loss in chronic septic total hip arthroplasty loosening

Abstract Background: When a periprosthetic infection is diagnosed, the surgical treatment is usually performed as soon as possible to avoid further bone damage or life threatening complications. There is no report on the radiographic change in patients with untreated infected total hip arthroplasty (THA) for several years. Objective: Report radiographic change in patients with untreated infected THA. Method: Two patients presented with chronic septic loosening of cemented acetabular fixation after total hip replacement at King Chulalongkorn Memorial Hospital. Both patients had mild hip pain and had been lost for follow-up until the bone destruction became very severe. Serial radiographs after the surgeries were evaluated. The Paprosky’s acetabular bone loss classification was used to classify the radiographic findings. Results: Based on the Paprosky’s classification for acetabular bone loss, there were two similar atypical radiographic findings found in both patients. These included pelvic discontinuity from extensive medial acetabular bone loss beyond the Kohler’s line, and minimal superior and inferior acetabular bone loss. Conclusion: These atypical radiographic findings were rarely observed in septic acetabular loosening patients, as infection usually causes patients to present earlier. Following the septic acetabular loosening of THA, surgical procedure should be performed before massive bone damage was demonstrated.

Atypical acetabular bone loss in chronic septic total hip arthroplasty loosening

Background: When a periprosthetic infection is diagnosed, the surgical treatment is usually performed as soon as possible to avoid further bone damage or life threatening complications. There is no report on the radiographic change in patients with untreated infected total hip arthroplasty (THA) for several years. Objective: Report radiographic change in patients with untreated infected THA. Method: Two patients presented with chronic septic loosening of cemented acetabular fixation after total hip replacement at King Chulalongkorn Memorial Hospital. Both patients had mild hip pain and had been lost for follow-up until the bone destruction became very severe. Serial radiographs after the surgeries were evaluated. The Paprosky’s acetabular bone loss classification was used to classify the radiographic findings. Results: Based on the Paprosky’s classification for acetabular bone loss, there were two similar atypical radiographic findings found in both patients. These included pelvic discontinuity from extensive medial acetabular bone loss beyond the Kohler’s line, and minimal superior and inferior acetabular bone loss. Conclusion: These atypical radiographic findings were rarely observed in septic acetabular loosening patients, as infection usually causes patients to present earlier. Following the septic acetabular loosening of THA, surgical procedure should be performed before massive bone damage was demonstrated. Keywords: Acetabular loosening, atypical, cemented fixation, radiographic finding, septic, total hip replacement

A shape-memory alloy internal fixator for treatment of acetabular fractures involving weight-bearing area

Objective To assess the mid-term results of acetabular three-dimensional memory fixation system (ATMFS) used to reconstruct weight-bearing area of the acetabulum. Methods From August 2003 to February 2009, totally 28 consecutive cases of unilateral severe fracture of the weight-bearing area of the posterior acetabular wall were treated with open reduction and ATMFS in our department. They were 19 males and 9 females, with a mean age of 39. 2 years (range, 18 to 70 years). Four fractures were old and 24 fresh. According to the Letournel & Judet classification system, there were 17 posterior wall fractures, 5 posterior column fractures, 5 transverse fractures, and one T-shaped fracture. According to the Zhang Chun-cai's classification system, the 28 cases all belonged to middle column-wall fracture, of which 19 were type Am1, 6 type Am2 and 3 type Am3. A modified hip posterolateral approach was adopted for all the patients. Results The 28 patients were followed up from 6 to 30 months (average, 8. 5 months). None of the patients lost reduction after surgery, and there was no case of implant failure. By Matta's criteria, 25 cases achieved anatomical reduction (89. 3% ) and 3 satisfactory reduction (10. 7% ) . All the patients achieved bony union in an average time of 12. 7 weeks after operation (from 11. 1 to 15. 0 weeks) . At the final follow-up, according to D' Aubigne & Postal's criteria, 92. 9% of the patients were rated as excellent or good.Conclusions ATMFS, as a wise biomechanical method to treat fractures involving weight-bearing area of the acetabulum, ensures stability of the hip joint, consistent compressive stress which promotes fracture union,and convenience of local grafting and reconstruction. It is an effective internal fixator for treatment of acetabular fractures involving weight-bearing area. Key words: Acetabulum; Fractures; Internal fixator

Biomechanical Study of Acetabular Tridimensional Memoryalloy Fixation System

We developed the acetabular tridimensional memoryalloy fixation system (ATMFS), which is made of NiTi shape memory alloy, according to the specific mechanical properties of biological memory material, NiTi shape memory alloy and measured distribution of contact area and pressure between the acetabulum and the femoral head of cadaveric pelvis. Seven formalin-preserved cadaveric pelves were used for this investigation. Pressure-sensitive film was used to measure contact area and pressure within the anterior, superior, and posterior regions of the acetabulum. The pelves were loaded under the following four conditions: (1) intact; (2) following a creation posterior wall fracture defect; (3) following reduction and standard internal fixation with reconstruction plate; and (4) following reduction and internal fixation with a new shape memory alloy device named ATMFS. A posterior wall fracture was created along an arc of 40° to 90° about the acetabulur rim. Creation of a posterior wall defect resulted in increased load in the superior acetabulum (1485 N) as compared to the intact condition (748 N, P = 0.009). Following reduction and internal fixation, the load distributed to the superior acetabulum (1545 N) was not statistically different from the defect condition. Following the fixation with ATMFS, the load seen at the superior region of the actabulum (964 N) was familiar with fixation with reconstruction plate and was not different from intact state (P = 0.45). These data indicate that the use of ATMFS as a fracture internal fixation device resulted a partial restoration of joint loading parameters toward the intact state. ATMFS fixation may result in a clinical benefit.

Componente acetabular no cementado en coxartrosis por fractura de cotilo

Objective To evaluate the outcomes of cementless acetabular component for post-traumatic arthritis after acetabular fracture. Material and method A prospective study of twenty-four patients with a mean age of 56 years (range: 28-77) and a follow-up 8.4 years (range: 5-15) treated with cementless total hip arthroplasty. The time from fracture to total hip arthroplasty was 3 years (range: 5 months-14 years). The fracture had been treated conservatively in 15 cases and with internal fixation in 9 cases. A clinical assessment was made using with Harris hip score, along with radiology with special interest in the socket. Results Harris hip score increased from 35 points (range: 22-52) to 77 (range: 45-94). Unstable acetabular fixation was seen in 3 cases, 2 with osteolysis that required revision and 1 with a complete radiolucent line. The stem required revision in 1 case. There was 1 case of deep infection and 1 post-traumatic late dislocation. Survival for any cause at 12 years was 78.4%. Discussion and conclusions There are few studies on this topic, and all with a small number of cases. Acetabular failure rate is higher than routine total hip arthroplasty for non-traumatic osteoarthritis. Cementless total hip arthroplasty is a suitable treatment for post-traumatic arthritis after acetabular fracture.

Early Postoperative Acetabular Discontinuity After Total Hip Arthroplasty

Periprosthetic acetabular fracture is a rare complication after total hip arthroplasty (THA). However, we have treated 2 patients with acute postoperative acetabular discontinuity that occurred 2 and 3 weeks after primary THA. Both fractures were in elderly osteoporotic female patients with minimal trauma and may have developed from unrecognized intraoperative fractures. Pelvic stability was restored with acetabular revision using medial morselized bone grafting and a cemented reconstruction cage. This report demonstrates that early postoperative periprosthetic acetabular discontinuity after THA is a risk in elderly patients with severe osteoporosis and that salvage of acetabular fixation can be achieved with cemented cage reconstruction and medial morselized bone grafting.

Migration of a Broken Drill Bit After Acetabular Fracture Fixation. A Case Report

Breakage of the drill bit is common in orthopaedic procedures, but migration of the broken drill bit is rarely reported. We report a case of migration of a broken drill bit five years after acetabular fracture fixation. The drill bit migrated to the subcutaneous layer of the anterior aspect of the right hip following total hip replacement. We highlight this case as it could be encountered in any orthopaedic procedure, and we support the recommendation to record such incidences in the medical notes and to inform the patient.

Crowe Type I and II Ddh Managed by Large Diameter Metal-on-Metal Total Hip Arthroplasty

Large bearing metal-on-metal (MOM) total hip arthroplasty (THA) may offer advantages relating to stability and range of motion in patients with Crowe Type I and II developmental dysplasia of the hip (DDH). The purpose of this study was to provide an analysis of the clinical and radiological results of MOM THA in this context and compare the results with a cohort of patients treated with metal-on-polyethylene (MOP) bearing surfaces. 75 hips in 65 patients were treated with cementless MOM THA using large femoral heads (36-56 mm). The mean age of the patients was 47.4 years (29 to 59) and 54 were female. A group of 47 hips (41 patients) treated with conventional THA (screwed cup-polyethylene insert-28 mm head) was used for comparison. The study group was followed up for a mean of 62.1 months (32 to 76). No difference was found between the two groups in relation to improvement in Harris hip score (HHS) (43.1 to 90.3 points in the study group, 42.6 to 89.5 points in the control group, p>0.05). Although the preoperative range of motion in all planes were similar in both groups, the large head group demonstrated greater motion in all planes postoperatively, which was significant (all p=0.001). Additionally, there was a significant difference between groups in relation to the necessity for acetabular structural graft (8% and 31.9%, respectively; p=0.001). No major complications or adverse reactions to metal debris (ARMD) were observed in the study group. The results of large head MOM THA in young and active patients with DDH are similar to conventional THA at early follow-up, but the former offers the advantages of secure acetabular fixation without screws, greater range of motion, and lower risk of dislocation.

Posterior trochanteric osteotomy provides adequate exposure for treatment of acetabular fractures

Objective To explore whether posterior trochanteric osteotomy can provide adequate exposure to facilitate surgery for acetabular fractures.Methods From January 2000 to January 2008, 32 cases of acetabular fracture involving the acetabular dome underwent posterior trochanteric osteotomy for a better exposure to facilitate internal fixation with acetabular tridimensional memory fixation system(ATMFS).Of the 32 cases, 28 were followed up.They were 16 men and 12 women, with a mean age of 39.9 years (16 to 73) .There were 19 fresh fractures and 9 old ones.Results Twenty-eight cases were followed up for an average of 48.9( 19 to 95) months .According to Matta criteria, anatomical reduction was achieved in 17 cases, satisfactory reduction in 10 cases, and unsatisfactory reduction in one old fracture.All the fractures got direct bony union with no displacement or deep infection.All the osteotomy fragments healed within 14 weeks without any nonunion, proximal migration, loosening or breakage of hardware or deep infection.Superficial infection occurred in one patient but healed after regular dressing.Two patients had to sustain removal of the implants from greater trochanter because of irritation.According to the Medical Research Council (MRC) grading system, the strength of the abductors was of Grade 4 in 3 patients, of Grade 3 in one patient and normal in the rest.By the modified d'Aubigne & Postel scoring system, the excellent to good rate was 89.3%.Conclusion Posterior trochanteric osteotomy can provide an adequate exposure of the acetabular dome without such complications as nonunion, proximal replacement or weakness of the abductors which often occur after the conventional oblique osteotomy. Key words: Acetabulum; Fractures; Osteotomy; Fracture fixation, internal

Cementless acetabular component in coxarthrosis due to a acetabular fracture

Objective To evaluate the outcomes of cementless acetabular component for post-traumatic arthritis after acetabular fracture. Material and method A prospective study of twenty-four patients with a mean age of 56 years (range: 28–77) and a follow-up 8.4 years (range: 5–15) treated with cementless total hip arthroplasty. The time from fracture to total hip arthroplasty was 3 years (range: 5 months-14 years). The fracture had been treated conservatively in 15 cases and with internal fixation in 9 cases. A clinical assessment was made using with Harris hip score, along with radiology with special interest in the socket. Results Harris hip score increased from 35 points (range: 22–52) to 77 (range: 45–94). Unstable acetabular fixation was seen in 3 cases, 2 with osteolysis that required revision and 1 with a complete radiolucent line. The stem required revision in 1 case. There was 1 case of deep infection and 1 post-traumatic late dislocation. Survival for any cause at 12 years was 78.4%. Discussion and conclusions There are few studies on this topic, and all with a small number of cases. Acetabular failure rate is higher than routine total hip arthroplasty for non-traumatic osteoarthritis. Cementless total hip arthroplasty is a suitable treatment for post-traumatic arthritis after acetabular fracture.

Large Acetabular Defects Can be Managed with Cementless Revision Components

Optimal techniques for acetabular revision in the setting of major pelvic osteolysis have not been established. Bilobed components, structural grafts, and reinforcement cages have demonstrated 10-24% midterm failure rates. While cementless hemispherical components have been utilized to treat large acetabular defects, most reports have not focused specifically on patients with extensive deficiencies. We report midterm clinical scores, component revisions, and complications following focal bone grafting and cementless acetabular revision in cases with major periacetabular osteolysis. We identified 30 patients (32 hips) who underwent cementless acetabular revision to treat massive acetabular bone loss at an average followup of 53 months. We excluded three patients lost to followup and two patients who died prior to minimum 24 month followup. Harris Hip Scores were assessed before and after surgery. Postoperative radiographs were evaluated for graft incorporation and component migration. Component revision and component migration are reported as failures. Mean Harris Hip Score improved from 52.5 (range, 17.7-90.7) to 87.3 (range, 25.3-100) points. Three hips (9%) were revised for aseptic loosening. Three components (10.7%) demonstrated radiographic migration, but were not revised. Complete graft incorporation was seen in 17 cases (68%). There were five major complications (14%). Cementless acetabular fixation and bone grafting result in clinical scores and survivorship comparable to other options at midterm followup, with potential for biological fixation. Level IV, clinical research study. See the Guidelines for Authors for a complete description of levels of evidence.

In Vivo Polyethylene Wear of Bilateral Total Hip Replacements - Cemented versus Uncemented Modular Sockets

We assessed polyethylene wear and osteolysis in 15 patients (30 hips) undergoing staged bilateral total hip arthroplasties, who had a cemented arthroplasty on one side and a hybrid arthroplasty on the other. All factors apart from mode of acetabular component fixation were matched. Wear was measured radiographically using Livermore's technique. The mean clinical and radiological follow-up was 11.2 years for the cemented and 10.7 years for the hybrid arthroplasties. Mean annual linear wear rate was 0.09mm/year in the cemented sockets and 0.14mm/year in the uncemented sockets. This difference was statistically significant (p=0.03), confirming previous reports that the rate of polyethylene wear is increased in uncemented sockets. No periacetabular osteolysis was noted. Femoral osteolysis in zone 7 occurred in 3 hybrid arthroplasties. It appears not all patients are equally affected. These results are further discussed.

The Results of a Press-Fit-Only Technique for Acetabular Fixation in Hip Dysplasia

The purpose of the present study was to evaluate the 6- to 11-year follow-up results of hemispherical porous-coated cups implanted into dysplastic hips using press-fit technique without screws focusing on the amount of host bone coverage. There were 87 patients who underwent 98 primary total hip arthroplasties. Bony coverage was measured as the angle between the vertical line and the line drawn from the cup center to the lateral edge of the acetabulum, which was named the cup center-edge angle (cup-CE angle). All 98 cups were judged to be bone ingrown. The minimum cup-CE angle was 8.4° (mean, 26.3°). Bone-cup contact of more than 8.4° of the cup-CE angle was large enough for press-fit cups to resist superior directed loads during this follow-up period.

Does An Enhanced Surface Finish Improve Acetabular Fixation in Revision Total Hip Arthroplasty?

High-porosity “cancellous metal” coatings have been introduced to increase the fixation and biologic incorporation of acetabular cups. The strength of initial fixation provided by a cancellous metal cups vs conventional alternatives in the deficient revision acetabulum was investigated. Cancellous, plasma-sprayed, and beaded cups (n = 9) were implanted under controlled conditions into a validated model of the revision acetabulum. The greatest differences were seen in resistance to catastrophic (spin-out) failure that, for the cancellous shell, averaged 1076 ± 265 N, which was 25% greater than the plasma-sprayed implant (859 ± 214 N, P = .04) and 218% greater than the beaded implant (338 ± 123 N, P < .01). The cancellous coating also provided greater resistance to ultimate failure. These results suggest that these new cancellous metal coatings may represent a promising alternative for fixation in revision total hip arthroplasty.