Acetabular Bone Deficiency Research Articles

The relationship between depth and diameter of the human acetabulum in the dry hip bone of Maharashtra population

Abstract Background: Anatomy of the hip must be taken into account to perform the various surgical procedures like reconstruction of the acetabulum in patients with significant acetabular bone deficiency. It remains a major challenge in total hip arthroplasty. Appropriate anatomic concepts for surgery to treat femoroacetabular impingement require a precise appreciation of the native acetabular anatomy. Since the acetabulum is not always of the same shape, width or depth, joint congruence is frequent with minor anatomical variations in the shape of the acetabulum. Hence, the present study was undertaken as controversies still exist on the importance of these variations and to prevent problems following surgical procedures such as acetabular reconstruction and femoroacetabular impingement. Method: 81 dry human hip bones of unknown sex were taken for observation from departments of anatomy at Dr SCGMC Nanded and SRTRGMC Ambajogai. All hip bones were adult-type. The exact age and sex of hip bones were not known. Measurements were taken in millimeters using a sliding digital vernier calliper. The mean and standard deviation of the acetabulum in various dimensions were calculated. Parameters of acetabulum depth and diameter were measured. Result: The overall goal of this study was to generate data that would be useful to the orthopaedics for geometric modelling. The study would also help the forensic experts. It would also be valuable for the anthropologists in their racial and population studies. The mean SD value of the depth of acetabulum on the right side is 27.121.02mm and on the left side is 27.021.03. The mean S.D. value of the diameter of the acetabulum on the right side is 47.501.27mm and on the left side is 47.451.33. Conclusion: Morphological study on adult hip bone is useful for anatomists, anthropologists, experts in forensic medicine and orthopaedics for performing surgical procedures in this area.

Impaction bone grafting for contained acetabular defects in total hip arthroplasty

BackgroundAcetabular bone loss is a technical challenge in total hip arthroplasty (THA). This study sought to report the functional and radiological results of acetabular reconstruction using impaction bone grafting (IBG) in patients with acetabular bone deficiency undergoing primary or revision THA.MethodsIn this prospective study, full history taking, preoperative clinical and radiological evaluation, and preoperative planning and templating were performed. The Paprosky classification and the American Academy of Orthopaedic Surgeons classification were used to assess the acetabular deficiencies. Clinical outcomes were assessed utilizing the Harris hip score (HHS) and a 4-question satisfaction questionnaire. Graft incorporation was evaluated in the last follow-up X-rays.ResultsThis study included 50 patients with a mean age of 46.7 ± 15.3 years. The THA was primary in 14 (28%) patients and revision in 36 (72%) patients. The mean HHS improved significantly from 28.8 ± 24.1 preoperatively to 76.6 ± 6.1, with a mean follow-up period of 23 months. Overall, 88% of patients were very satisfied. Complete radiological graft incorporation to host bone was achieved in 35 (70%) patients, and the remaining patients had partial incorporation. Complete graft incorporation was associated more frequently with primary THA, autografts, cementless cups, decreased defect size, and decreased graft layer thickness.ConclusionsIBG for acetabular reconstruction in THA can achieve excellent clinical and radiological outcomes with a low complication rate.Level of evidenceLevel IV.

Long-term follow-up of 96 patients younger than age 25 with 119 primary cemented total hip arthroplasties.

Long-term follow-up of young patients following cemented primary THA is scarce. Therefore, we analyzed the survival of all consecutive primary THAs in patients under 25 years performed at our institute. All primary THAs performed in patients younger than 25 years in our tertiary care institute between 1988 and 2015 were included (n = 119). Cemented fixation was used in all patients. In the case of acetabular bone deficiencies, reconstruction was performed using impaction bone grafting (IBG). We used Kaplan-Meier analysis to determine the survival of the primary THA with endpoints revision for any reason and aseptic loosening. The mean age at the primary THA was 20 years. The most prevalent diagnosis was avascular necrosis (31%). The mean follow-up of the primary THA was 11 years (range 0-32). 2 patients (2 hips) were lost to follow-up. 16 revisions were registered. The survival of any component for endpoint revision for any reason was estimated at 92% (95% confidence interval [CI] 84-96) and 81% (CI 67-90) at 10- and 15-year follow-up, respectively. The survival of any component for endpoint revision for aseptic loosening was 99% (CI 93-100) and 88% (CI 71-95) at 10 and 15 years, respectively. 3 hips were revised due to infection. Favorable long-term outcomes of primary THA in very young patients can be obtained using cemented fixation and IBG.

Pre-operative planning and templating with 3-D printed models for complex primary and revision total hip arthroplasty

BackgroundComplex primary and revision THR requires comprehensive understanding of abnormal bony anatomy. Evaluation and classification of acetabular bone defects is essential to manage them appropriately. It is difficult to appreciate complex defects using conventional 2-Dimensional radiological modalities. 3D printed models can provide both visual and tactile reproduction of the bony anatomy, with potential for better pre-operative planning and making these complex surgeries more precise and accurate. Materials and methodsAnatomical 3D models of pelvis and femur were made based on CT scans of 27 patients undergoing complex primary THR/Revision THR by FDM (Fusion Deposition Modeling) technology using Flash Forge–Dreamer 3D printer with ABS (plastic) material. Models were used for pre-operative planning and simulation of surgery. Aims of the study were to study the accuracy of 3D models in predicting the implant sizes, accuracy in evaluation of acetabular bone defects and validating the utility of 3 D models through surgeon feedback. ResultsThe acetabular cup size and placement was accurate in 25 (92.6%) patients. Preoperative acetabular bone defect was accurately estimated in all the patients. There were no neurovascular complications at early and 1-year follow-up in this case series. Model realism and reliability survey response from five surgeons was graded, with average overall usefulness of 3D models of 4.86/5, average model realism was 4.9/5, average usefulness for planning was 4.74/5 and usefulness for teaching was 5/5. Conclusion3D models are accurate and help in assessing acetabular bone deficiencies reliably in complex and revision THR. Anatomical models help in surgical planning and simulation, enabling surgeons in predicting the correct implant sizes and importantly placement of acetabular cup and for management of bone defects. The safe trajectory of acetabular screws can be simulated and determined, thereby avoiding penetration into pelvis and neuro-vascular injuries.

Functional and radiological outcomes of impaction grafts and cemented cup for the treatment of acetabular bone deficiency in total hip arthroplasty

Background and Aim Acetabular bone defects are one of the most difficult problems in both primary and revision total hip replacements. Many techniques have been described to deal with acetabular bone defects in total hip replacement, including the use of cement with or without cages and rings, structural bone grafting, and impaction bone grafts with cementless or cemented cups. The aim of this study was to asses short-term to midterm clinical and radiological outcomes of acetabular reconstruction by impaction bone grafts and cemented cups in both primary and revision cases indicated for total hip arthroplasty (THA) with acetabular bone deficiency. Patients and methods This is a retrospective study that included 26 patients with total hip arthroplasty (THA) who underwent acetabular bone defect reconstructions with grafting and cemented cups between December 2014 and January 2019. The mean age at operation was 45.3 years. Among the procedures, 12 were primary THAs, whereas 14 procedures were revision THAs. The morselized grafts were used in eight cases only, along with combined strut graft and morselized grafts in five cases, acetabular rim mesh and morselized grafts in 12 cases, and Kerboul cross-ring with morselized grafts in one case. All cases were clinically evaluated by Harris hip score in addition to radiological evaluation. Results All the patients except one showed clinical improvement, where the mean postoperative Harris hip score became 84. Radiograph follow-up for all the cases showed graft incorporation without loosening or any significant cup migration, except one case, which was revised owing to loosening around the cup. Conclusion The use of impaction graft and cemented cups is safe and reproductive even in young patients. Moreover, this technique reconstitutes bone and gives a stable platform of bone stock for further revision, especially in young population.

Robotic-Assisted Total Hip Arthroplasty in Patients Who Have Developmental Hip Dysplasia

Introduction: Total hip arthroplasty (THA) in the setting of developmental dysplasia of the hip (DDH) presents more inherent complexities than routine primary THA for osteoarthritis. These include acetabular bone deficiency, limb length discrepancy (LLD), and abnormal femoral anteversion. Three-dimensional planning and robot-assisted (RA) bone preparation may simplify these complex procedures and make them more reproducible. The purpose of this study was to evaluate radiographic and clinical outcomes in a cohort of patients who had DDH and underwent an RA THA. Materials and Methods: We retrospectively analyzed 26 DDH patients who underwent RA THA by a single surgeon between 2013 and 2019. Their mean age was 54 years (range, 29 to 72 years) and mean follow up was approximately two years. Medical records were reviewed for demographics, clinical scores, Crowe classifications, and complications. There were thirteen Crowe I and seven Crowe II DDH hips, who were routinely managed with primary cementless implants. Two patients who had Crowe III and four patients who had Crowe IV DDH were also identified. All hips were reconstructed with cementless hemispherical acetabular components with or without the use of screws, but no acetabular augments or bulk allografts. Implants allowing control of femoral anteversion were selected in 23.1% of cases, including all six cases with Crowe III or IV dysplasia, and the need for these implants was uniformly identified using preoperative information about femoral version provided by the three-dimensional planning software. No patient was managed with a shortening femoral osteotomy. Postoperative radiographs were examined for LLD, center of rotation (COR), cup position (inclination and anteversion), and component osseous-integration. Results: Mean radiographic LLD was 1.7mm (range, -9 to +14) in patients who had Crowe I DDH, and there was no clinical LLDs greater than 5mm observed. Although patients who had Crowe II and greater DDH had a mean radiographic LLD of -11.6mm (range, -26 to +2.2), again no clinical LLD greater than 5mm was observed other than one patient who had bilateral Crowe II DDH in whom 10mm of clinical lengthening was accepted at the index arthroplasty with the plan to match lengths when her contralateral THA was performed. There were no cases of dislocation or acetabular fixation failure. One patient who had a femoral deformity and an intra-osseous blade plate from a prior femoral osteotomy suffered a failure of femoral osseous-integration, resulting in revision. A 32-point increase in mean modified Harris Hip Score (mHHS) was found (p=0.002), from 48 points preoperatively to 80 points postoperatively. Discussion: RA THA provides an excellent option for the arthroplasty surgeon to both preoperatively localize and characterize the acetabular deficiency, while providing a targeted, optimal, and secure placement of the components intraoperatively. Our results suggest favorable outcomes when compared to previous research on manual THA in DDH. Further studies, including comparative analyses, could discern possible advantages over traditional THA without robotic assistance in DDH. Conclusion: Total hip arthroplasty (THA) in the setting of developmental dysplasia presents more inherent complexities than routine primary THA. Robotic-assisted THA may simplify these complex procedures.

Augmentation for Acetabular Deficiencies in Complex Total Hip Arthroplasty

Introduction:Complex and revision Total Hip Arthroplasty (THA) is a challenging prospect in patients with acetabular bone deficiencies. Augmentation using allograft and trabecular metal (TM) are among some of the options in these situations. This study report the outcomes of 14 cases of complex and revision THA using acetabular augments performed in our institution between 2015 and 2018Materials and Methods:In this retrospective study, data included demographic features, indication for THA, type of augments and clinical outcomes using the Harris hip score were collected for the to determine early results following THA.Results:The mean cohort age was 51.3 years. Gender distribution was equal with 7 male and female patients each. 7 THAs were augmented with allograft and 7 cases with TM augments. The average duration of follow-up was 16.9 months. Most patients (11 of 14) required complex primary THA following prior traumatic hip dislocations and its subsequent complications. The mean post-operative Harris hip score for functionality was 80.84 in our cohort at final follow-up (from an average of 33.8 pre-operatively). At present, there have been no reports of wound complications, infections or dislocations in this early cohort.Discussions:Complex/revision THA using allografts for acetabular augmentation have been used for decades with good and replicable results as shown in our series. TM is relatively new but current literatures show encouraging results. Both options have resulted in good outcomes in our cohort and further long term studies would be necessary before TM augments were to replace the need for allograft.Conclusions:Both allografts and TM acetabular augments showed good early results post-operatively in our cohort. With the improved flexibility of component selection and the lower risk of allograft infection, TM augments is currently our choice of acetabular augmentation and the early results are promising.

Total hip arthroplasty using hydroxyapatite-coated cementless cup for rapidly destructive coxarthrosis: Minimum 10-year follow-up

BackgroundPerforming total hip arthroplasty (THA) as early as possible is recommended for rapidly destructive coxarthrosis (RDC) as it causes pain that becomes progressively more severe. However, acetabular bone loss remains an issue in THA. Special devices, such as a Kerboull-type plate, may be used for acetabular bone defects, but the procedure is highly invasive and often the patients are elderly, further complicating matters. We retrospectively investigated the clinical and radiographic results of THA using conventional hydroxyapatite-coated cementless cup in RDC. MethodsA total of 32 patients (35 hips) with RDC were enrolled in the study with a minimum 10-year follow-up. All THAs were performed using conventional hydroxyapatite-coated cementless cup. All patients were evaluated clinically according to the Harris hip score (HHS). Acetabular bone deficiency was classified according to the American Academy of Orthopaedic Surgeons (AAOS) classification. ResultsEleven hips (31%) were AAOS type III, and none were type IV. Total HHS significantly improved from 36.5 to 79.4 (p < 0.01). Two cups exhibited loosening. The overall implant-associated survival rate after 10 years was 91.4%. ConclusionsClinical results of THA using conventional cementless implants for patients with RDC were acceptable. Thus, THA using conventional cementless implant is an effective and safe surgery for patients with RDC, minimizing surgical stress.

Primary Total Hip Arthroplasty in Severe Dysplastic Hip Osteoarthritis With a Far Proximal Cup Position

BackgroundDevelopmental hip dysplasia is the most common cause of secondary hip osteoarthritis. Due to severe acetabular bone deficiency, cup positioning in total hip arthroplasty (THA) of dysplastic hips remains a surgical challenge. The aim was to analyze the functional outcome of far proximal cup positions in primary THA. MethodsFifty patients (61 hips) with THA for severe dysplastic osteoarthritis and a far proximal cup position were included. Patients were divided according to the heights of the implanted cups with increasing vertical distance from the interteardrop line (group A: 55-65 mm, group B: 65-75 mm, group C: >75 mm). Functional outcome was assessed at latest follow-up (38 ± 16 months) by Lower Extremity Functional Score, Tegner Activity Score, and Harris Hip Score (HHS). Patients answered a Patient Satisfaction Questionnaire. Leg length discrepancy was estimated radiographically. ResultsThe Lower Extremity Functional Score significantly decreased in C (45.3 ± 25) compared to A (66.7 ± 15.3) and B (67.9 ± 9.9). The Tegner Activity Score significantly increased in all subgroups from preoperative to postoperative (2.2 ± 1.3 to 4.1 ± 1.4; P < .05). The mean overall HHS was 89.3 ± 14.7 (A: 89.5 ± 14.3, B: 94.3 ± 6.5, C: 78.3 ± 22.1). The HHS domains of activity of daily life and gait were significantly reduced in C (P < .05). Patients described a high satisfaction level with the surgery. No significant differences were found with regard to preoperative and postoperative leg lengthening (P = .881). Neither dislocations, impingement problems nor neurologic complications were observed. ConclusionPrimary THA without any concomitant surgical interventions with a far proximal cup position offers a safe and effective treatment option in severe dysplastic hip osteoarthritis.

Three-Dimensional Models in Planning of Revision Hip Arthroplasty with Complex Acetabular Defects.

Background:Careful preoperative planning in revision cases with complex acetabular defects is crucial for optimal surgery outcome. However, in many cases, computed tomography (CT) scans cannot give a clear understanding of the pelvic destruction. Three-dimensional (3D) models-based on CT data can help surgeon in planning of complex acetabular reconstruction.Materials and Methods:We used 3D plaster pelvic models in 17 revision cases. There were 5 patients with Paprosky II C acetabular defects, 2 patients with Paprosky IIIA defects, and 10 patients with Paprosky IIIB defects (3 patients among them with pelvic discontinuity). We used 3D printer and digital 3D models based on CT scan data for 3D models printing. In 3 cases with Paprosky IIIB defects, we implanted custom-made acetabular components with the porous coating, also printed on the 3D printer.Results:In 14 cases, we used trabecular metal (TM) augments with TM cups. In 100% of cases, number and type of planned and used augments were same. In 9 (64.3%) cases, size of planned and used cups was same. In other cases, the difference was not >2 mm.Conclusions:Use of 3D plaster models for the revision hip arthroplasty planning with complex acetabular defects has shown high accuracy in the clear understanding of acetabular bone deficiency.

Long-term results of isolated acetabular revisions with reinforcement rings: a 10- to 15-year follow-up.

The management of severe acetabular bone deficiency and a stable femoral stem can be a challenging problem in revision hip surgery. Replacement of both the acetabular and femoral component in elderly patients can increase perioperative risks without the certainty of a better functional outcome. We report the long-term outcome of reinforcement rings in isolated acetabular revision to determine whether this procedure allows hip function restoration and implant longevity. A retrospective study was conducted to evaluate the long-term results of isolated acetabular revision in thirty patients with a mean age of 70.6 years. 16 patients (16 hips) received an acetabular reinforcement ring, and 14 patients received a reconstruction cage. Acetabular defects were classified as Paprosky Type II in 16 cases and Type III in 14 cases. The mean follow-up was 11.3 years (range 10-15 years). Radiographic signs of loosening were found in 9 cases (30%). 4 cases (13.3%) with severe osteolysis and implant migration underwent further revision surgery. All 30 unrevised femoral stems were considered stable. 1 (3%) early dislocation, was conservatively treated. Clinical assessment showed a significantly improved mean Harris Hip Score from 45.1 points preoperatively to 85.4 at the latest follow-up (p < 0.05). The 15-year survival rate was 86.7%. Our long-term results showed that in selected patients, isolated acetabular revision with rings or antiprotrusio cages represents a reasonable surgical technique for the management of severe acetabular bone loss. However, concerns about the high radiographic loosening rates are possibly related to low bone ingrowth compared to new porous implants.

Gestione dei difetti acetabolari: l’uso di osso omologo

Bone grafts are implanted materials that support or promote bone healing through an osteogenic, osteoconductive and/or osteoinductive mechanism to the local site. Acetabular bone deficiencies encountered during acetabular hip arthroplasty revision vary from cavitary or segmental defects to complete discontinuity. Several techniques exist to manage these defects. In this review we present the current surgical techniques for reconstructing the acetabular socket which includes a cementless acetabular component with morselised bone, structural allograft, reinforcement rings and bone cages. Segmental acetabular defects involving both columns with more than 50% of the graft supporting the cup suggest the application of ilioischial devices. The aim is to bridge areas of bone loss, providing immediate mechanical fixation. Acetabular reconstruction with the use of the antiprotrusion cage and allografts has to be considered as a reliable procedure to manage severe periprosthetic deficiencies with highly successful long-term outcomes in revision arthroplasty.

Revision Total Hip Arthroplasty Using a Cementless Cup Supporter and Iliac Autograft: A Minimum of 15-Year Follow-Up

BackgroundBone deficiency in revision total hip arthroplasty is a surgical challenge. The Murata-Chiba cup supporter (MC support ring) is an acetabular component supporter for a cementless porous-coated cup. The purpose of this study is to examine the clinical and radiographic outcomes of reconstruction of acetabular bone deficiency using iliac autografts supported by an MC support ring in a revision setting with minimum 15-year follow-up. MethodsFifty-nine consecutive revision total hip arthroplasties (57 patients) using the MC support ring were followed for a minimum of 15 years. Nine hips had American Academy of Orthopaedic Surgeons type II deficiency and 24 had type III defects of the acetabulum. Clinical outcomes were evaluated using the Harris hip score. Radiographic evaluation included assessment for loosening and bone graft incorporation. Kaplan-Meier survival analysis was performed. ResultsAt a minimum 15-year follow-up (mean, 17.6 years), 32 patients (33 hips) were alive, 17 patients (18 hips) were deceased, and 8 patients (8 hips) were lost to follow-up. The mean Harris hip score improved from 44.3 to 77.2 at final follow-up. Four hips required reoperation due to deep infection (2 hips) and liner dissociation (2 hips), but no acetabular components were revised for aseptic loosening. Incorporation of the bone graft occurred in all cases. One unrevised patient had radiographic failure. Survivorship at 15 years with re-revision or radiographic failure as the end point was 90.6% (95% confidence interval, 83.0%-98.8%). ConclusionThe reconstruction of acetabular bone deficiency using autografts supported by an MC support ring provided satisfactory clinical and radiological results at 17.6 years postoperatively.

Structural Allograft Supporting a Trabecular Metal Cup Provides Durable Results in Complex Revision Arthroplasty

BackgroundRevision total hip arthroplasty (THA) is challenging specially in the presence of severe acetabular bone deficiency. We report the use of a highly porous revision shell augmented by structural allograft to provide structural support and coverage to the acetabular component. MethodsWe identified 56 patients (58 hips) undergoing revision THA, where a trabecular metal revision cup was supported by structural allograft. Mean follow-up was 5.4 years (range 2-12 years). Preoperatively acetabular bone defects were classified as Paprosky 2A in 6 hips (10%), 2B in 12 hips (21%), 2C in 12 hips (21%), 3A in 11 hips (19%), and 3B in 17 hips (29%). Structural allograft configuration was classified as type 1 (flying buttress) in 13 hips, type 2 (dome support) in 23 hips, and type 3 (footings) in 17 hips, with 5 hips having combined configurations. ResultsAll hips showed evidence of union between the allograft and host bone at latest follow-up, 14 hips had partial resorption of the allograft that did not affect cup stability. Three acetabular components demonstrated failure of ingrowth. Survivorship-free from radiographic acetabular loosening as end point was 94% at 5 years. The 5-year survivorship with revision for any reason as end point was 90%. ConclusionTrabecular metal shells combined with structural bone allograft in revision THA demonstrate excellent midterm survival, with 94% of acetabular components obtaining stable union onto host bone at 5 years. Allograft restored bone stock with minimal resorption, and when it occurred did not alter the survivorship of the acetabular component.

Short-term outcomes of using cup-cage for revision hip arthroplasty in severe acetabular bone deficiency

Objective To investigate the short-term outcomes after revision hip arthroplasty for severe acetabular bone deficiency by cup-cage. Methods We retrospectively analyzed 16 patients (16 hips) with Paprosky type ⅢB acetabular bone deficiency, who received cup-cage from October 2013 to May 2016. There were 6 males and 10 females, with an average age of 62.6 years (range 40-84 years). All but one patient were with pelvic discontinuity. The reason for revision was aseptic loosening for 14 patients and periprosthetic joint infection for 2. Eleven patients underwent surgery via Trabecular Metal Acetabular Revision System (cup+cage), 2 via Trabecular Metal cup and AR cage, and 3 via R3 cup and AR cage. During the follow-up, Harris hip score was recorded to evaluate the clinical efficacy, and X-rays were performed to identify the signs of loosening and changes in rotation center position. Results The mean follow-up was 18.7 months (range 6-36 months). The height of rotation center was decreased from 42.00±12.18 mm preoperatively to 22.75±8.44 mm postoperatively, whereas the horizontal distance of the rotation center was 26.81±7.61 mm preoperatively and 32.50±6.51 mm postoperatively (t=8.249, P<0.001; t=-4.786, P<0.001). The height of the rotation center was slightly higher than that of the contralateral side postoperatively (t=-3.478, P=0.003), whereas the difference in the horizontal distance of the rotation center between the two groups was not statistically significant (t=1.235, P=0.236). The Harris hip score was improved from 45.63±11.68 preoperatively to 75.78±9.12 postoperatively (t=-12.157, P<0.001). During the follow-up, one dislocation occurred at 5 days postoperatively and closed reduction was conducted under anesthesia. There was no blood vessel injury, nerve injury, wound complication and periprosthetic joint infection. No recurrence of infection occurred in 2 patients who received revision hip arthroplasty for periprosthetic joint infection. Conclusion Revision hip arthroplasty for PaproskyⅢB acetabular bone deficiency by cup-cage can achieve good primary stability and reconstruct the rotation center, especially for patient with pelvic discontinuity. Key words: Arthroplasty, replacement, hip; Reoperation; Acetabulum

The clinical application of custom 3D-printed acetabular filling technology in complicated hip arthroplasty

Objective To observe and summarize the clinical efficacy and surgical experience of 3D printing technology in hip arthroplasty for severe acetabular bone deficiency. Methods 3D printing was applied to 11 complicated hip surgeries for Paprosky Ⅳ acetabular bone deficiency. The imaging data of the patients were captured and utilized to build CAD models. These data were converted and input to 3D printer to print the model of defected acetabular bone. Meanwhile, defected acetabulum was repaired with active titanium filling through hip arthroplasty, to reconstruct the rotation center of the hips and implant hip joint prosthesis. Imaging data and Harris hip score were monitored after the surgeries. Results The Harris hip scores of the 11 patients were 46.6±10.7 before surgeries, and imaging data indicated severe acetabular bone deficiency. After surgeries, imaging data presented that the acetabular bone deficiency was repaired by printed filling. Moreover, rotation center was reconstructed successfully. The Harris hip score became 85.2±4.5 at 6th month after the surgeries, which showed satisfactory clinical efficacy. Conclusion 3D-printing technology implemented in hip surgeries for Paprosky Ⅳ acetabular bone deficiency can be successfully utilized to mock surgery, print acetabular filling and improve the efficacy and success rate of the surgery. Key words: 3D-printing technology; Hip arthroplasty; Acetabular bone deficiency

Application of jumbo cup in acetabular revisions for patients with massive acetabular bone deficiency

Objective To investigate the effects of the jumbo cup in acetabular revision for patients with massive acetabular bone deficiency. Methods We retrospectively studies 48 patients (49 hips) who underwent jumbo cup revisions between 2006 and 2015 (19 men and 29 women; average age: 62±12 years). The acetabular bone defects were classified according to Paprosky classification (Paprosky II 27 hips, Paprosky IIIA 18 hips, Paprosky IIIB 4 hips). Radiological assessments were conduced to evaluate the acetabular prosthesis loosening, dislocation and infection. The reasons for revisions were mechanical loosening in 41 cases, and infections in another 8 cases with cement spacer putted by last surgery. Results The operation duration and blood loss was 110 min (85-160 min) and 315 ml (270-455 ml) respectively. After an average follow-up of 6.8 years (1-11 years), Harris hip score was increased from 47.6 ± 7.1 preoperatively to 82.4 ± 6.2 postoperatively. Osseointegration occurred in the acetabular components at 6 months postoperatively. Radiograph analysis showed satisfied position of acetabular cup without complications such as damages of vessels or nerves. The successful rate of jumbo cup revisions was 89.8%±4.4%. However, two in Paprosky IIIA failures for periprosthetic infection occurred and two in Paprosky IIIA, one in Paprosky IIIA and the other in Paprosky IIIB for acetabular component loosening. One patient in Paprosky IIIB had weight-bearing pain and relieve slightly after conservative treatment. The radiologic study showed that there was no relationship between failure rate and acetabular abduction angle (r=0.06, P= 0.53), rotation center migration in vertical direction (r=0.11, P=0.14) and horizontal direction (r=0.04, P=0.89). Conclusion The mid-term results show that using jumbo cup in revising acetabular failure with massive bone deficiency are optimal, which can be achieved by simplified operation procedures, reduction in the need of bone graft and promotion in acetabulum osseointegration. However, higher failure rate may occur in Paprosky IIIB patients. Key words: Arthroplasty, replacement, hip; Reoperation; Acetabulum; Osteolysis; Prosthesis failure

Clinical results of arthroscopic suture for meniscal tear in middle aged adults

To study the characteristics and clinical effect of total hip arthroplasty(THA) for osteoarthritis and (or) avascular necrosis of femoral head after failure of internal fixation of acetabular fracture. From February 2009 to October 2014, 31 patients (31 hips) with hip traumatic osteoarthritis and (or) femoral head avascular necrosis after failure of internal fixation of acetabular fracture were treated with THA including 26 males and 5 females, who injured when the average age of(41±12) years. THA were performed, and the duration ranged from 3 to 132 months with a mean of(20.6±26.9) months secondary to traumatic osteoarthritis and(or) femoral head avascular necrosis. All THA were performed with posterior-lateral approach. The postoperative complications were observed. VAS and Harris hip scores were compared pre-operation and post-operation. Twenty-seven cases were followed up, and the duration ranged from 12 to 80 months with a mean of (43.2±11.7) months. One patient had infection around prosthesis. Aseptic loosening occurred in 1 patient, dislocation of prosthesis in 1 patient. No sciatic nerve injury occurred. Hip function and gaits were obviously improved. To the last follow-up, VAS score was decreased from 7.6±1.2 pre-operatively to 1.2±0.9 post-operatively, while the Harris score was improved from 45.5±13.6 pre-operatively to 88.5±7.8 post-operatively, both differences were statistically significant(P<0.01). The post-operative ROM of hip was significantly improved compared to pre-operative ROM(P<0.05), in addition to extension motion. X-ray showed all the acetabular cups were stable, one femur stem subsided 3 mm. Heterotopic ossification occurred in 2 cases. Correct dealing with of internal fixation implants, looking out potential infection and reasonable reconstruction of acetabular bone deficiency were the key to the success of THA for osteoarthritis and(or) avascular necrosis of femoral head after failure of internal fixation of acetabular fracture.

Midterm outcome of total hip arthroplasty for rapidly destructive coxarthrosis.

To compare the midterm outcome in 12 women who underwent total hip arthroplasty (THA) for rapidly destructive coxarthrosis (RDC) and in 12 controls who underwent THA for osteoarthritis. Records of 12 women aged 50 to 80 (mean, 72.3) years who underwent THA for RDC after a mean of 9 (range, 4-11) months since symptom onset were reviewed. They were compared with 12 age-and sex-matched controls who underwent THA for primary or secondary osteoarthritis. Acetabular bone deficiency of the 12 RDC patients was classified as type I (n=7), type II (n=4), or type III (n=1). Type I was treated with cementless THA, and types II and III were treated with THA with a cemented acetabular component. The femoral component was cementless. Pre- and post-operative Harris Hip Score was assessed. Radiographs of the hip were evaluated for implant migration, osteolysis, and periprosthetic radiolucency in the acetabulum and proximal femur. The 12 women who underwent THA for RDC and the 12 controls who underwent THA for osteoarthritis were comparable in terms of pre-, intra-, and post-operative parameters. After a mean follow-up of 9.3 years, the mean Harris Hip Score improved from 38.3 to 81.1 in RDC patients and from 43.6 to 84.2 in controls (p=0.13). One RDC patient had dislocation but did not require revision surgery. One RDC patient developed a radiolucent line <2 mm in zones 1 and 7 of the femoral component, but no migration occurred. No patient had progression of bony destruction, loosening, osteolysis, migration, or radiolucency of the acetabular component. Despite the rapid destruction of the acetabulum and femoral head in RDC patients, cemented or cementless THA achieved a good midterm outcome comparable to that for patients with primary or secondary osteoarthritis.

A cemented cup with acetabular impaction bone grafting is more cost-effective than an uncemented cup in patients under 50 years.

Acetabular deficiencies in young patients can be restored in several ways during total hip arthroplasty. Currently, cementless cups are most frequently used. Impaction bone grafting of acetabular defects is a more biological approach, but is it cost-effective in young patients on the long term? We designed a decision model for a cost-utility analysis of a cemented cup with acetabular impaction bone grafting versus an uncemented cup, in terms of cost per quality-adjusted life year (QALY) for the young adult with acetabular bone deficiency, in need for a primary total hip arthroplasty. Outcome probabilities and effectiveness were derived from the Radboud University Nijmegen Medical Centre and the Norwegian Hip Register. Multiple sensitivity analyses were used to assess the contribution of the included variables in the model's outcome. Cemented cups with impaction bone grafting were more cost-effective compared to the uncemented option in terms of costs per QALY. A scenario suggesting equal primary survival rates of both cemented and uncemented cups still showed an effect gain of the cemented cup with impaction bone grafting, but at higher costs. Based on this model, the first choice of treatment of the acetabular bone deficient osteoarthritic hip in a young patient is reconstruction with impaction bone grafting and a cemented cup.