Paprosky Type IIIA Research Articles

RECONSTRUCTION OF PAPROSKY TYPE III ACETABULAR BONE DEFECTS IN REVISION HIP ARTHROPLASTY USING A COMBINATION OF CAGE AND MORSELIZED ALLOGRAFTS

The management of severe acetabular bone defects poses a complex challenge in revision hip arthroplasty. Although biological fixation materials are currently dominant, cage has played an important role in complex acetabular revision in the past decades, especially when a biological prosthesis is not available. The purpose of this study is to report the long-term clinical and radiographic results of Paprosky type Ⅲ acetabular bone defects revised with cage and morselized allografts.We retrospectively analyzed 45 patients who underwent revision hip arthroplasty with cage and morselized allografts between January 2007 and January 2019. Forty-three patients were followed up. There were 19 Paprosky type IIIA bone defect patients and 24 Paprosky type IIIB bone defect patients and 7 patients of the 24 were also with pelvic discontinuity. Clinical assessment included Harris Hip Score (HHS) and Short Form-12 (SF-12). Radiographic assessment included cage stability, allografts incorporation, and center of rotation.All patients were followed up with a mean follow-up of 10.6 years, HHS and SF-12 improved significantly at last follow-up in comparison to the preoperative. There were 2 re-revisions, one at 5 years after surgery, another at 13.6 years after surgery. Two patients had nonprogressive radiolucency in zone III and the junction of zone II and zone III at the bone implant interface. Allografts of 40 (93%) cases incorporated fully.The combination of cage and morselized allograft is an alternative option for acetabular revision with Paprosky type III bone defects with satisfactory long-term follow-up results.

3D-printed Personalized Porous Acetabular Component to Reconstruct Extensive Acetabular Bone Defects in Primary Hip Arthroplasty.

Management of extensive acetabular bone defects in total hip arthroplasty (THA) remains challenging. This study aims to investigate the feasibility and preliminary outcomes of 3D-printed personalized porous acetabular components for the reconstruction of acetabular defects in primary THA. This retrospective study involved seven patients who received 3D-printed acetabular components in primary THA between July 2018 and March 2021. Preoperatively, acetabular bone defects were evaluated by referencing the Paprosky classification. There were two "Paprosky type IIIA" defects and five "Paprosky type IIIB" defects. The acetabular components were custom-made for each patient to reconstruct the extensive acetabular defects. The hip function was assessed according to the Harris hip score (HHS). Clinical and radiographic outcomes were assessed. The average follow-up period was 40 months, ranging from 26 to 57 months. There were no patients lost to follow-up. The HHS improved from 44 (range: 33-53) before the operation to 88 (range: 79-93) at the final follow-up. Postoperative X-rays showed that the 3D-printed personalized components were properly fitted with the acetabulum. The average center of rotation (COR) discrepancy was 2.3 mm horizontally and 2.1 mm vertically, respectively. Tomosynthesis-Shimadzu metal artifact reduction technology images showed that the implant was in close contact with the host bone. Moreover, no complications were observed during the follow-up period, including loosening, dislocation, or component protrusion. The implantation of 3D-printed personalized acetabular components showed accurate reconstruction, stable mechanical support, and favorable function at short-term follow-up. This may be a viable alternative method for reconstructing extensive acetabular defects in THA.

Highly Porous Acetabular Cup and Augment Constructs in Complex Revision Total Hip Arthroplasty: What Predicts 10-Year Implant Survivorship?

BackgroundPorous tantalum acetabular cup and augment constructs have demonstrated favorable outcomes up to 5 years postsurgery despite severe bone loss during revision total hip arthroplasty (THA). Prior literature lacks long-term studies with substantial case numbers. This study aims to assess long-term clinical and radiographic outcomes 10 years postsurgery in patients undergoing revision THA with porous tantalum acetabular cup-augment constructs and determine factors associated with long-term survivorship. MethodsBetween 2000 and 2012, 157 revision THAs were performed in cases with major acetabular defects (mainly Paprosky type IIIA and IIIB) utilizing porous tantalum cup-augment constructs. Pelvic discontinuity was noted intraoperatively in 17 hips (11%). Postoperative radiographs were evaluated at regular intervals for implant stability and radiolucent lines. There were 49 patients who had complete radiographic follow-up at 10 years or longer postsurgery. ResultsThe 10-year survivorship free of revision of the cup-augment construct for aseptic loosening was 93%, free of any acetabular construct revision was 91%, free of any hip rerevision was 77%, and free of any reoperation was 75%. Pelvic discontinuity was associated with increased risk of reoperation (hazard ratio [HR] = 2.8), any hip rerevision (HR = 3.2), any cup-augment construct revision (HR = 11.8), and aseptic construct revision (HR = 10.0). Of unrevised cases with radiographs at 10 years, 4 hips showed radiographic loosening. Mean Harris hip scores improved from 47 preoperatively to 79 at 10 years. ConclusionsPorous tantalum acetabular cup-augment constructs used in revision THA with severe acetabular bone loss provide excellent implant survivorship at 10 years when the acetabulum is intact. Due to lower survivorship of cup-augment constructs in cases of pelvic discontinuity, additional construct fixation or stabilization methods are recommended, when a discontinuity is present. Level of EvidenceIV

Revision total hip arthroplasty using a modular fluted, tapered revision femoral component and interlocking screws in Vancouver B3 periprosthetic fractures with insufficient bone at the isthmus.

Revision total hip arthroplasty in patients with Vancouver type B3 fractures with Paprosky type IIIA, IIIB, and IV femoral defects are difficult to treat. One option for Paprovsky type IIIB and IV defects involves modular cementless, tapered, revision femoral components in conjunction with distal interlocking screws. The aim of this study was to analyze the rate of reoperations and complications and union of the fracture, subsidence of the stem, mortality, and the clinical outcomes in these patients. A total of 46 femoral components in patients with Vancouver B3 fractures (23 with Paprosky type IIIA, 19 with type IIIB, and four with type IV defects) in 46 patients were revised with a transfemoral approach using a modular, tapered, cementless revision Revitan curved femoral component with distal cone-in-cone fixation and prospectively followed for a mean of 48.8 months (SD 23.9; 24 to 112). The mean age of the patients was 80.4 years (66 to 100). Additional distal interlocking was also used in 23 fractures in which distal cone-in-cone fixation in the isthmus was < 3 cm. One patient (2.2%) died during the first postoperative year. After six months, 43 patients (93.5%) had osseous, and three had fibrous consolidation of the fracture and the bony flap, 42 (91.3%) had bony ingrowth and four had stable fibrous fixation of the stem. No patient had radiolucency around the interlocking screws and no screw broke. One patient had non-progressive subsidence and two had a dislocation. The mean Harris Hip Score increased from of 57.8 points (SD 7.9) three months postoperatively to 76.1 points (SD 10.7) 24 months postoperatively. The 2° tapered, fluted revision femoral component with distal cone-in-cone-fixation, combined with additional distal interlocking in patients with bony deficiency at the isthmus, led to reproducibly good results in patients with a Vancouver B3 fracture and Paprosky type IIIA, IIIB, and IV defects with regard to union of the fracture, subsidence or loosening of the stem, and clinical outcomes.

The use of an individual acetabular component for acetabular defect: a clinical case

BACKGROUND: The incidence of total hip replacements is increasing every year. Acetabular defects are becoming more frequent, with Paprosky type IIIA and above becoming more common. Recently, customized 3D-printed constructs have been used to remodel severe defects. We wanted to demonstrate the possibility of treating a patient with a severe acetabular defect by performing a one-stage revision endoprosthesis using a customized design.&#x0D; CLINICAL CASES DESCRIPTION: A 69-year-old patient underwent primary total hip replacement of the right hip joint with a Biomet endoprosthesis for coxarthrosis in 2010. In 2011 on the left side with a Zimmer endoprosthesis. In 2013 revision endoprosthesis of the right hip joint due to instability was preformed. In the postoperative period, there were repeated dislocations with subsequent closed repositioning. In 2015, revision endoprosthetic replacement with a Burkh-Schneider antiprotrusion ring was done for recurrent dislocation. In november 2017, she was diagnosed with instability of the right total hip joint, for which she underwent revision hip replacement with a customized acetabular component.&#x0D; HHS score before revision arthroplasty was 18 points, 1 month after surgery 75 points, after 3 months 65, after 6 months 82, after 4 years 74. Quality of life was assessed using the WOMAC scale: 92 points before surgery, 38 points 1 month after surgery, 31 points in 3 months, 15 points in 6 months, and 35 points in 4 years. As of the last visit, the patient moves with a cane, and still has a limp due to scar remodeling and gluteal muscles atrophy.&#x0D; CONCLUSION: In case of severe acetabular defects, the use of individual components allows achieving reliable "implantbone" fixation, which leads to improved functional results. However, in chronic pelvic bone integrity defects, the use of an individual acetabular component does not always achieve reliable stabilization. All existing methods for solving this problem are currently ambiguous and require further improvement.

Bridging Massive Acetabular Defects With the Triflange Cup: 10- to 28-Year Results

BackgroundMassive acetabular bone loss, encountered complex primary or revision total hip arthroplasty, remains a reconstructive challenge. The custom triflange cup reliably achieves both early fixation and longer-term stability. This study presents the 10-year minimum three-surgeon follow-up of acetabular defects managed with a custom triflange component. MethodsAll patients who underwent a custom triflange acetabular component implantation from January 1992 to December 2009 were identified. Demographics, implant data, outcomes, and reoperations were collected and analyzed. Bone defects in all cases were Paprosky type IIIA, IIIB, or IV. A total of 233 patients (241 hips) underwent implantation of a custom triflange during the study period. There were 81 patients (83 hips) who died prior to minimum follow-up and 84 patients (88 hips) had minimum follow-up of 10 years (mean 15.2; range, 10 to 28), or failure prior to 10 years. ResultsComplications requiring additional surgery occurred in 43 hips (49%). There were 10 revisions for failure (11.4%); four were due to recurrent infection, three for aseptic loosening, and one for recurrent infection with all revised to a new triflange. There was one patient who was resected to a Girdlestone for infection and one patient was revised for infection to a bipolar hemiprosthesis due to a healed discontinuity. ConclusionTo our knowledge, this study represents the largest cohort and longest follow-up in the current literature and demonstrates excellent survivorship and clinical results at an average of 15 years follow-up. The component was retained in 89% of cases.

Revision Total Hip Arthroplasty Utilizing an Acetabular Reinforcement Ring with a Metal Augment: A Minimum Eight-Year Follow-Up Study.

Background and Objectives: An acetabular reinforcement ring (ARR) with a structural allograft is conventionally used to treat large acetabular bone defects or discontinuity during revision hip arthroplasty. However, ARR is prone to failure due to bone resorption and lack of incorporation. Here, we investigated the surgical outcomes of the patients who underwent revision total hip arthroplasty (THA) using ARR combined with a metal augment (MA). Materials and Methods: We retrospectively reviewed data from 10 consecutive patients who had a minimum 8-year follow-up after revision hip arthroplasty using ARR with MA in Paprosky type III acetabular defect. We collected patient demographics, surgical details, clinical scores (including Harris Hip Score (HHS)), postoperative complications, and 8-year survival rates. Results: Six male and four female patients were included. The mean age was 64.3 years, and the mean follow-up duration was 104.3 months (96.0-112.0 months). Trauma-related diagnosis was the most common reason for index surgery. Three patients underwent all component revision, and seven underwent cup revision. Six were confirmed as Paprosky type IIIA and four as type IIIB. The mean HHS at the final follow-up was 81.5 (72-91). One patient was diagnosed with prosthetic joint infection at the 3-month follow-up; therefore, the minimum 8-year survival rate with our technique was 90.0% (95% confidence interval, 90.3-118.5%). Conclusions: The satisfactory mid- to long-term results of revision THA suggest that ARR combined with tantalum MA is a viable revision option for treating severe acetabular defects with pelvic discontinuity.

Translated article] Trabecular titanium implants in complex acetabular revision surgery

IntroductionAcetabular revision surgery is a surgical challenge, especially when complex bone defects appear. This makes primary fixation and osseointegration of the implants difficult, which conditions the appearance of complications. Trabecular titanium implants attempt to solve these problems. ObjectivesTo evaluate our clinical-radiological results, the survival of the implants and the appearance of mid-term complications in acetabular revision surgery in a series of 37 acetabular replacements with Paprosky type IIIA and IIIB bone defects in which a trabecular titanium Cup-Cage revision implant was used. Material and methodWe conducted an observational, descriptive and retrospective study of 37 cases with complex acetabular defects (20 type IIIA and 17 type IIIB, five of them with pelvic discontinuity) in which the acetabular component was replaced by trabecular titanium cups between 2011 and 2019. We analysed clinical results (pain and functionality) and radiological parameters (restoration of the hip rotation centre and the mobilisation of the implants), as well as the appearance of complications. ResultsThe mean follow-up was 61 months. We obtained a median improvement of 8 points on the Merlé D’Aubigné-Postel functionality scale and 6 points on the VAS scale of pain perceived by the patient. We recorded two cases of acetabular loosening, one case of dislocation and three surgical wound infections without affecting the implant. ConclusionsThe use of trabecular titanium Cup-Cage implants could be a valid option in acetabular revision surgery with complex acetabular defects, presenting good clinical and radiological results and in terms of complications and survival of the implants, mainly due to their good primary fixation and subsequent osseointegration.

Implantes de titanio trabecular en cirugía de revisión acetabular compleja

IntroductionAcetabular revision surgery is a surgical challenge, especially when complex bone defects appear. This makes primary fixation and osseointegration of the implants difficult, which conditions the appearance of complications. Trabecular titanium implants attempt to solve these problems. ObjectivesTo evaluate our clinical-radiological results, the survival of the implants and the appearance of mid-term complications in acetabular revision surgery in a series of 37 acetabular replacements with Paprosky type IIIA and IIIB bone defects in which a trabecular titanium Cup-Cage revision implant was used. Material and methodWe conducted an observational, descriptive and retrospective study of 37 cases with complex acetabular defects (20 type IIIA and 17 type IIIB, five of them with pelvic discontinuity) in which the acetabular component was replaced by trabecular titanium cups between 2011 and 2019. We analyzed clinical results (pain and functionality) and radiological parameters (restoration of the hip rotation centre and the mobilization of the implants), as well as the appearance of complications. ResultsThe mean follow-up was 61 months. We obtained a median improvement of 8 points on the Merlé D’Aubigné-Postel functionality scale and 6 points on the VAS scale of pain perceived by the patient. We recorded two cases of acetabular loosening, one case of dislocation and three surgical wound infections without affecting the implant. ConclusionsThe use of trabecular titanium Cup-Cage implants could be a valid option in acetabular revision surgery with complex acetabular defects, presenting good clinical and radiological results and in terms of complications and survival of the implants, mainly due to their good primary fixation and subsequent osseointegration.

Long-term results of combined porous tantalum augments and titanium-coated cups for Paprosky type III bone defects in acetabular revision.

The use of porous tantalum augments and titanium-coated cups in primary total hip arthroplasty (THA) with acetabular defects has shown satisfactory outcomes in our centre. The aim of this study was to report the long-term radiological and clinical outcomes of using this combination for Paprosky type III acetabular bone defects in acetabular revision. Between January 2007 and January 2015, 45 patients with Paprosky type III acetabular defects underwent acetabular revision using a combination of porous tantalum augments and titanium-coated cups. Among these, 41 patients (41 hips) had complete follow-up. Thirty-one patients had a Paprosky type IIIA defect, and ten patients had a Paprosky type IIIB defect. No patients had pelvic discontinuity. There were 20 males and 21 females with an average age of 63.2years (range 35-80) at the time of revision surgery. The mean follow-up was 122.8months (range 69-165). The Harris Hip Score (HHS) improved significantly from 32.1 points (range 17-58) pre-operatively to 85.3 points (63-98) at the last follow-up. The Short Form-12 (SF-12) and Hip Dysfunction and Osteoarthritis Outcome Score (HOOS) improved significantly for each item at the last follow-up. Two patients had a high hip centre post-operatively. One patient had recurrent dislocation but did not require re-revision. No further revision of the acetabular components was required, and all hips remained stable at the last follow-up with bony ingrowth of the acetabular components according to the criteria of Moore et al. CONCLUSION: The combination of tantalum augments and conventional titanium-coated cups achieved satisfactory long-term radiographic and clinical outcomes for Paprosky type III acetabular bone defects without pelvic discontinuity.

Impaction bone grafting in hip re-revision surgery.

Bone stock restoration of acetabular bone defects using impaction bone grafting (IBG) in total hip arthroplasty may facilitate future re-revision in the event of failure of the reconstruction. We hypothesized that the acetabular bone defect during re-revision surgery after IBG was smaller than during the previous revision surgery. The clinical and radiological results of re-revisions with repeated use of IBG were also analyzed. In a series of 382 acetabular revisions using IBG and a cemented component, 45 hips (45 patients) that had failed due to aseptic loosening were re-revised between 1992 and 2016. Acetabular bone defects graded according to Paprosky during the first and the re-revision surgery were compared. Clinical and radiological findings were analyzed over time. Survival analysis was performed using a competing risk analysis. Intraoperative bone defect during the initial revision included 19 Paprosky type IIIA and 29 Paprosky type IIIB hips; at re-revision, seven hips were Paprosky type II, 27 type IIIA and 11 were type IIIB (p = 0.020). The mean preoperative Harris Hip Score was 45.4 (SD 6.4), becoming 80.7 (SD 12.7) at the final follow-up. In all, 12 hips showed radiological migration of the acetabular component, and three required further revision surgery. The nine-year cumulative failure incidence (nine patients at risk) of the acetabular component for further revision surgery was 9.6% (95% confidence interval (CI) 2.9 to 21.0) for any cause, and 7.5% (95% CI 1.9 to 18.5) for aseptic loosening. Hips with a greater hip height had a higher risk for radiological migration (odds ratio 1.09, 95% CI 1.02 to 1.17; p = 0.008). Bone stock restoration can be obtained using IBG in revision hip surgery. This technique is also useful in re-revision surgery; however, a better surgical technique including a closer distance to hip rotation centre could decrease the risk of radiological migration of the acetabular component. A longer follow-up is required to assess potential fixation deterioration. Cite this article: Bone Joint J2021;103-B(3):492-499.

Modular tapered conical revision stem in hip revision surgery: mid- term results

BackgroundThe aim of this paper is to evaluate the clinical and radiological outcomes of a fluted tapered modular distal-fixation stem at medium to long-term follow-up. The hypothesis of this investigation was to verify if the use of this implant design may have provided potential advantages in femoral revisions and post-traumatic instances where the restoration of the anatomy was the prime concern.MethodsWe retrospectively reviewed 62 cases of femoral revision surgeries, performed in Paprosky type IIIA and IIIB bone defects between January 2001 and December 2011 with a mean follow-up of 8.5 ± 1.5 years (range 5.1–15.9 years) where a modular fluted stem was used. The clinical assessment was performed with the Harris Hip Score (HHS), and the radiographic evaluation was carried in order to assess the stability of the femoral component. Intra-operative and postoperative complications were recorded, and the rates of complications and revisions for any cause were determined.ResultsMean HHS improved 35.4 points from the preoperative assessment. Radiographic evaluation showed a stable stem anchorage in 90.3% of the cases at the last follow-up. Five (8%) implants required additional surgery. Neither breakage of the stem nor loosening of the taper junction were recorded. Kaplan-Meier survivorship was 89.4% (CI: 88.8–90%) for any complication and 92.3% (CI: 91.8–92.7%) according to revision for any causes at 81 months follow-up.ConclusionsOur findings suggest that this stem design is a reliable option in cases of complex femoral bone defects, as well as in cases with high functional deficiencies, with promising survivorship.

Cup-on-cup technique: a reliable management solution for severe acetabular bone loss in revision total hip replacement.

The management of acetabular bone loss is a challenging problem in revision total hip arthroplasty (rTHA). The goals of treatment are a stable acetabular fixation, implant stability, and restoration of hip centre of rotation.This study aims to report clinical, radiological outcomes and complications at short-term to mid-term follow-up of the cup-on-cup technique in the management of severe acetabular bone loss in rTHA. We retrospectively reviewed the records of patient receiving rTHA performed with double porous tantalum cup technique in a single Joint Replacement Unit from 2014 to 2017. Objective and subjective clinical scores (Harris Hip Score, Oxford Hip Score, and visual analogue scale), radiological parameters (centre of rotation, leg-length discrepancy, heterotopic ossification, osseointegration, loosening and radiolucencies) and complications were recorded. We analysed the implant survival rate and periprosthetic joint infection rate. We included 9 patients (9 hips) with a mean follow-up of 35.3 ± 10.8 months. Functional scores showed a statistically significant improvement at the final follow-up (p < 0.01). All patients rated their surgery as satisfactory. The cup-on-cup construct demonstrated radiological osseointegration with the centre of rotation restoration and leg length discrepancy improvement. In 1 patient, periprosthetic joint infection was diagnosed and treated with suppressive antibiotic therapy. No patients underwent acetabular components revision surgery for any reason. Cup-on-cup technique is a valid and safe solution for reconstruction of selected Paprosky type IIIA and IIIB bone defects with satisfactory clinical and radiographic results at short-term and mid-term follow-up.

Tantalum Augments Combined with Antiprotrusio Cages for Massive Acetabular Defects in Revision Arthroplasty

BackgroundTantalum components have gained popularity for the management of Paprosky type IIIA and IIIB defects during revision total hip arthroplasty. Although the use of antiprotrusio cages solely shows suboptimal results, there are certain defects that still require their use. We hypothesized that combining tantalum augments and an antiprotrusio cage would (1) improve radiographic stability, (2) enhance survivorship, (3) decrease complications, and (4) improve clinical outcomes. MethodsWe retrospectively reviewed 20 patients with Paprosky type IIIA or IIIB defects who underwent revision of the acetabular component with a highly porous tantalum augment and an antiprotrusio cage combination. Preoperative and postoperative radiographs, survivorship free from aseptic component revision, and the Harris Hip Score, Western Ontario and McMaster Universities Osteoarthritis Index, and Short Form-36 scores were analyzed. The mean follow-up was 2.8 years. ResultsAt the most recent follow-up, no antiprotrusio cages had migrated and all tantalum augments had radiographic evidence of osseointegration. In addition, only 2 components were revised for aseptic etiologies and only 1 was loose. Both were revised secondary to failures of the inferior flange of the antiprotrusio cage. All clinical outcome scores significantly improved postoperatively. Finally, the risk of major postoperative complications was noted to be 10%. ConclusionsIn summary, a tantalum augment combined with an antiprotrusio cage in Paprosky IIIA and IIIB defects with divergent anatomy not amenable to a hemispherical socket provides a reliable technique to restore the anatomic hip center and prevent superior migration and provides a bony ingrowth surface. Longer term follow-up is required before the technique is widely adapted. Level of EvidenceLevel IV, therapeutic studies.

Minimum 8-year follow-up of revision THA with severe femoral bone defects using extensively porous-coated stems and cortical strut allografts

BackgroundRevision total hip arthroplasty (THA) with severe femoral bone defects remains a major challenge. The purpose of this study is to report the minimum 8-year clinical and radiographic results of revision THA with severe femoral bone defects treated with extensively porous-coated stems and cortical strut allografts.MethodsWe retrospectively identified 44 patients diagnosed with Paprosky type III and IV femoral bone defects between January 2006 and July 2011. The exclusion criteria were patients not eligible for surgery, revised with extensively porous-coated stems alone, lost to follow-up and deceased. A total of 31 patients treated with extensively porous-coated stems and cortical strut allografts were finally included in this study. The degree of femoral bone defects was categorized as Paprosky type IIIA in 19 patients, type IIIB in 9 patients and type IV in 3 patients. The mean duration of follow-up was 11.0 ± 1.5 (range, 8.1–13.5) years.ResultsThe mean Harris Hip Score improved significantly from 43.4 ± 10.5 points to 85.2 ± 6.6 points (P < 0.001). Similarly, WOMAC and SF-12 scores also significantly improved. Twenty-eight stems achieved stable bone ingrowth, two stems showed stable fibrous ingrowth, and one stem was radiologically unstable. Complete union and bridging between cortical strut allografts and host bone was achieved in all 31 patients. The femoral width was augmented with cortical strut allografts after revision surgery (an increase of 10.5 ± 0.5 mm) and showed a slight decrease of 2.5 ± 4.8 mm after the 10-year follow-up. Using re-revision for any reason as an endpoint, the Kaplan-Meier cumulative survival rate of the stem was 96.2% (95% confidence interval, 75.7–99.5%) at 10 years.ConclusionOur data demonstrate that the use of extensively porous-coated stems combined with cortical strut allografts in revision THA with Paprosky type III and IV femoral bone defects can provide satisfactory clinical and radiographic outcomes with a minimum follow-up of 8 years.

Stemmed acetabular cup as a salvage implant for revision total hip arthroplasty with Paprosky type IIIA and IIIB acetabular bone loss

IntroductionCertain cases of repeated acetabular loosening with severe bone loss are hardly amenable to reconstruction using a Kerboull-type plate with allograft. This limitation is more likely when the severe bone loss occurs in older adults with significant comorbidities that may require a faster procedure. In these indications, a stemmed acetabular cup may be an alternative, although the outcomes have not been well defined, especially for a version where the peg is coated with porous material and additional screws can be added. This led us to conduct a retrospective study to determine: (1) whether a stemmed cup anchored in the iliac isthmus is a viable alternative in these situations, (2) the complication rate and (3) the revision rate for any reason. HypothesisA stemmed cup anchored in the iliac isthmus is a viable alternative in cases of repeated revision with severe acetabular bone loss. Materials and methodsWe performed a retrospective single-center study. Sixteen Integra™ cups were implanted in 14 patients (mean age 72.8±10.4 years, minimum–maximum: 58–95) who had aseptic acetabular loosening combined with severe acetabular bone loss graded as Paprosky IIIA in 7 hips and IIIB in 9 hips. The patients had undergone a mean of 2.7±1.8 (minimum–maximum: 1–6) procedures (i.e. primary and/or revision arthroplasty) before this cup was implanted. The cup's survivorship at the time of review and the complication rate were determined. ResultsAt a mean follow-up of 48.8±23.4 months (minimum–maximum: 7–85), two patients had died and two were lost to follow-up. Six hips experienced one or more complications (37.5%): three infections (18.8%), two mechanical failures (12.5%) and one dislocation (6.7%). The cup had to be removed in three patients (18.8%). These complications required reoperation, thus the cumulative incidence of revision for any reason at 5 years was 31% (95% CI: 11–55%). ConclusionDespite the high complication and revision rates, we believe the stemmed acetabular cup is a viable alternative in salvage reconstruction procedures. Level of evidenceIV, Retrospective case study.

Short- and mid-term effectiveness of impaction bone allograft with acetabular components in treatment of severe acetabular defects

To investigate the short- and mid-term effectiveness of revision hip arthroplasty by using impaction bone allograft and acetabular components in treatment of severe acetabular defects. A clinical data of 42 patients (44 hips) with severe acetabular defects between February 2011 and May 2018 were retrospectively analyzed. All patients underwent revision hip arthroplasty by using impaction bone allograft and acetabular components. Cemented cup (24 cases, 24 hips) and non-cemented cup (18 cases, 20 hips) were used in the revision surgery. There were 17 males and 25 females with an average age of 62.8 years (range, 22-84 years). The interval between the first total hip arthroplasty and revision was 2.5-12.0 years (mean, 8.3 years). The patients were accepted revision surgery for prosthesis aseptic loosening in 32 hips (31 cases) and the periprosthetic infection in 12 hips (11 cases). Twenty-nine hips (28 cases) were Paprosky type ⅢA and 15 hips (14 cases) were type ⅢB. The preoperative Harris score was 22.25±10.31 and the height of hip rotation center was (3.67±0.63) cm and the length difference of lower limbs was (3.41±0.64) cm. The operation time was 130-245 minutes (mean, 186 minutes) and the intraoperative blood loss was 600-2 400 mL (mean, 840 mL). The postoperative drainage volume was 250-1 450 mL (mean, 556 mL). Superficial infection of the incision occurred in 1 case, and the incisions healed by first intention in the other patients. All patients were followed up 6-87 months, with an average of 48.6 months. At last follow-up, the Harris score was 85.85±9.31, which was significantly different from the preoperative score ( t=18.563, P=0.000). Imaging examination revealed that the allogeneic bone gradually fused with the host bone, and no obvious bone resorption was observed. At last follow-up, the height of the hip rotation center was (1.01±0.21) cm, which was significantly different from the preoperative level ( t=17.549, P=0.000); the length difference of lower limbs was (0.62±0.51) cm, which was significantly different from the preoperative level ( t=14.211, P=0.000). The Harris score in the cemented group and non-cemented group increased significantly at last follow-up. The height of the hip rotation center decreased, and the hip rotation centers of both groups were within the Ranawat triangle zone. The length difference of the lower limbs also decreased, and the differences in all indexes were significant between pre- and post-operation ( P<0.05). There was significant difference in the height of the hip rotation center between groups ( t=2.095, P=0.042), but there was no significant difference in the Harris score and the length difference of lower limbs between groups ( P>0.05). For severe acetabular defect (Paprosky type Ⅲ), the hip can be reconstructed with the impaction bone allograft and cemented or non-cemented components in revision hip arthroplsty. The short- and mid-term effectiveness are satisfactory.

Reconstruction for pelvic discontinuity and massive acetabular defects

ObjectiveThe acetabular reconstruction with massive acetabular defects and pelvic discontinuity is a complex surgery with important difficulties for the orthopaedic surgeon. The objective of this study is to show the short and midterm results of the acetabular revision with the Cup-Cage construct in a consecutive series of cases. Material and methodsRetrospectively we reviewed 22 consecutive patients with massive acetabular defects (8 Paprosky IIIa and 9 IIIB); 5 pelvic discontinuities; 2 pelvic fractures during the implantation of primary arthroplasty, and one pelvic pseudoarthrosis. All were reoperated with a trabecular metal acetabular component and a Cup-Cage. We did clinical and radiological follow-up to detect mechanical failures and loosening of the implant. ResultsWith a middle follow-up of 45.06 months (12–73 months) we did not see any radiographic failure of the implant (component migration, osteolysis neither rupture of the implant or screws). The complications (13.63%) included one recurrent luxation, one infection and one recurrent subluxation. The Merle d’Aubigné-Postel score improved from 6.91 to 14.36 and the punctuation in the range of motion from 2.91 to 4.36 on average of the values preoperatively and postoperatively respectively and improvement in Harris Hip Score 30 (16–55) to 72 (40–90) in the latest follow up. ConclusionThe acetabular reconstruction with the Cup-Cage system is a valid alternative for the reconstruction of massive acetabular defects (Paprosky type IIIA and IIIB) and pelvic discontinuities offering good results at short and midterm follow-up.

Short-term effectiveness of acetabular reconstruction with three-dimensional printed trabecular metal pads in hip revision

To investigate the short-term effectiveness of three-dimensional (3D) printed trabecular metal pads for Paprosky type Ⅲ acetabular defect in hip revision. Between August 2014 and December 2015, the 3D printed trabecular metal pads were used to repair Paprosky type Ⅲ acetabular defects and reconstruct the annular structure of the acetabulums in 5 cases of primary hip revision. There were 3 males and 2 females, aged from 50 to 72 years, with an average age of 66 years. The time from initial replacement to revision was 10 to 18 years, with an average of 14.4 years. The types of prostheses in primary replacement were non-cemented in 3 cases and cemented in 2 cases. The types of acetabular bone defects were Paprosky type ⅢA in 3 cases and Paprosky type ⅢB in 2 cases. The preoperative Harris score was 34.23±11.67. The height of rotation center of affected hip was (38.17±8.87) mm and the horizontal position was (35.62±9.12) mm. The operation time was 120-180 minutes, with an average of 142 minutes. The intraoperative bleeding volume was 800-1 700 mL, with an average of 1 100 mL. Five patients were followed up 18-24 months (mean, 21 months). At last follow-up, the Harris score was 79.82±8.70, which was significantly higher than that before operation (t=16.991, P=0.000). At 1 week after operation, the abduction angle of acetabular cup was 38-42° (mean, 39.4 °) and the anteversion angle was 13-18 ° (mean, 14.6°). The height and horizontal position of rotation center of affected hip were (22.08±8.33) mm and (29.03±6.28) mm, respectively, showing significant differences when compared with those before operation (P<0.05); there was no significant difference when compared with those of healthy hip [(28.62±7.73), (27.29±4.22) mm] (P>0.05). During the follow-up, there was no complication such as prosthesis loosening, dislocation, or periprosthetic fracture. In hip revision, 3D printed trabecular metal pads can repair Paprosky type Ⅲ acetabular defect, reconstruct the structure of acetabulum, provide a stable supporting structure for the acetabular cup, reconstruct the relatively normal rotation center of the hip joint, avoid iatrogenic bone loss, and achieve satisfactory functional recovery of the hip. The long-term effectiveness needs further follow-up.

Mid-term results after revision total hip arthroplasty with custom-made acetabular implants in patients with Paprosky III acetabular bone loss.

Severe acetabular bone loss, both with or without pelvic discontinuity, remains a challenge in revision total hip arthroplasty (RTHA). The goal of our study was to evaluate the mid-term results for consecutive patients with Paprosky III acetabular bone loss with or without pelvic discontinuity who needed RTHA with custom-made acetabular implants and to compare the results to those of other studies. Sixty-eight (68) patients with severe acetabular bone loss (Paprosky Type IIIa and IIIb), who required RTHA, were included in our study. All prostheses were constructed on the basis of thin-layer computed tomography (CT) scans of the pelvis. The visual analogue scale (VAS), Harrison hip score (HHS), and clinical and radiographic follow-up assessments were used to evaluate the outcome. The average follow-up time was 43months (range 1-120months). Implant survival at last follow-up was 75% (51 of 68). Kaplan-Meier survival analysis, with explantation as the endpoint, revealed survival rates of 82.7% (3years) and 77% (5years). Patients with revision of the acetabular component only had a significant higher survival rate (p 0.012). Overall revision rate was 36.7%. Reinfection rate was 34.4%. Complications included 15 (22%) periprosthetic joint infections (PJI), 7 dislocations (10.2%), and 2 aseptic loosenings (2.9%). Mean VAS at last follow-up was 1.45 compared to 3.2 preoperatively, while mean HHS improved from 21.1 points preoperatively to 61 at last follow-up. The change in both scores was thus significant (p < 0.001). Defect reconstruction with custom-made modular acetabular implants can be a good, nevertheless expensive, treatment option with clinically and radiologically satisfying results in comparison to recent studies in the literature. Nevertheless, high postoperative complication rates, especially in terms of PJI, remain a challenge.