Morselized Bone Graft Research Articles

A sliding stem in revision total knee arthroplasty provides stability and reduces stress shielding

Background and purpose In the reconstruction of unicondylar femoral bone defects with morselized bone grafts in revision total knee arthroplasty, a stem extension appears to be critical to obtain adequate mechanical stability. Whether stability is still assured by this reconstruction technique in bicondylar defects has not been assessed. The disadvantage of relatively stiff stem extensions is that bone resorption is promoted due to stress shielding. We therefore designed a stem that would permit axial sliding movements of the articulating part relative to the intramedullary stem.Methods This stem was used in the reconstruction with impaction bone grafting (IBG) of 5 synthetic distal femora with a bicondylar defect. A cyclically axial load was applied to the prosthetic condyles to assess the stability of the reconstruction. Radiostereometry was used to determine the migrations of the femoral component with a rigidly connected stem, a sliding stem, and no stem extension.Results We found a stable reconstruction of the bicondylar femoral defects with IBG in the case of a rigidly connected stem. After disconnecting the stem, the femoral component showed substantially more migrations. With a sliding stem, rotational migrations were similar to those of a rigidly connected stem. However, the sliding stem allowed proximal migration of the condylar component, thereby compressing the IBG.Interpretation The presence of a functional stem extension is important for the stability of a bicondylar reconstruction. A sliding stem provides adequate stability, while stress shielding is reduced because compressive contact forces are still transmitted to the distal femoral bone.

Compaction Bone Grafting in Tibial Plateau Fracture Fixation

Displaced tibial plateau fractures are traditionally treated with internal fixation using autologous bone grafting to provide structural support. In comminuted and osteoporotic fractures, there can be insufficient autograft available for this. Fresh-frozen bone allograft is readily available in sufficient quantity to fill all voids, is relatively inexpensive, and avoids donor site morbidity. We describe our technique and the early clinical and radiologic results of compaction morselized bone grafting (CMBG) for displaced tibial plateau fractures using fresh-frozen allograft. This technique has been performed since July 2006 on eight patients. One patient died of an unrelated cause 3 months after surgery and one patient failed to attend follow-up clinic. Clinical and radiologic follow-up was performed on the remaining six patients at an average 15 months (range, 12-19) after surgery. One patient underwent a manipulation under anesthesia at 3 months for knee stiffness. One patient developed a painless valgus deformity and underwent a corrective osteotomy at 15 months. The height of the tibial plateau on radiographs has been maintained to an excellent grade (less than 2 mm depression) in all but one patient. CMBG using fresh-frozen allograft in depressed tibial plateau fractures provides structural support sufficient to maintain the height of the tibial plateau, is associated with few complications in complex patients with large bone loss, and has theoretical advantages of graft incorporation and remodeling.

Long-term results of the ABG-1 hydroxyapatite coated total hip arthroplasty: Analysis of 111 cases with a minimum follow-up of 10 years

Medium-term studies of ABG-1 cementless total hip arthroplasty have shown favorable functional results with excellent femoral component fixation but an abnormally high rate of periacetabular component osteolysis, which may require early revision. The periacetabular osteolysis rate increases with time with the ABG-1 implant, leading to a high revision rate. The objective of this study was to test this hypothesis with a minimum follow-up of 10 years and evaluate the progression of periacetabular osteolysis and its consequences on implant fixation. A continuous series of 111 ABG-1 cementless prostheses implanted by a single operator with a theoretical minimum follow-up of 10 years. Seventy-five implants were analyzed with a mean follow-up of 13 years. All the prostheses had been implanted via a posterolateral approach and consisted of a 28 mm cup matching a head in zirconia and an antidislocation rim design high-density polyethylene insert. Twelve cups were revised because of progressive retroacetabular osteolysis. The revisions were performed systematically although there was no pain or gross cup loosening. The revisions included resection of the granuloma, cavity filling with morselized bone grafts, and implantation of new uncemented ABG-2 cups in eight cases or cemented cups associated with a support ring in the four other cases. Thirty-two (48.5%) of the cups still in place at the end of the follow-up evaluation presented moderate and asymptomatic radiographic osteolysis, inciting close subsequent observation. No predictive factor of osteolysis onset was identified (age, body mass index, polyethylene wear, or cup orientation). None of the femoral stems was changed because of osteolysis: the only two femoral revisions resulted from periprosthetic fracture and one case of bipolar loosening. The femoral osteolysis images were small and all limited to zones 7a (18.8% of cases), 1a, and 1b (65.2% of cases). The overall survival rate of the series at 13 years of follow-up was 80.5%; the cup survival rate was 83.2%; the femoral implant, 94.3%; and failure of the femoral stem secondary to aseptic loosening was only 1.3%. This long-term study confirms the high frequency of retroacetabular osteolysis of ABG-1 prostheses surpassing the osteolysis rate of other uncemented cups with a polyethylene insert. The absence of predictive criteria of osteolysis occurrence and the lack of symptoms warrants periodic follow-up of patients with ABG-1 cups and, if necessary, early repair of bone stock loss with grafts combined with acetabular cup revision. This procedure remains simple as long as performed before the onset of massive bone destruction, confirming the proposed revisions in this series were judicious. This study also confirms the excellent long-term fixation of the ABG-1 femoral stems derived from the osteointegration and proximal seal around the hydroxyapatite coating.

Reconstruction of acetabular bone deficiency in total hip arthroplasty

To discuss the characteristics and reconstruction strategies of acetabular bone deficiency in total hip arthroplasty in order to find the optimal resolution for this clinical puzzle. Clinical and radiological materials of 37 patients (37 hips) with acetabular deficiency who underwent primary or revision total hip arthroplasty were analyzed retrospectively from May 1998 to August 2008. According to the common classification system for acetabular bone deficiency-the AAOS classification system, the acetabular bone defect was reconstructed using morselized or structural bone grafting, accessory acetabular hardware (ring, cup or cage) together with cemented or cementless acetabular component respectively. All patients were followed up regularly to assess their hip function improvement by measuring the Harris hip score and to find out the grafting bone healing, absorption and position of the prosthesis by plain radiographic examination. There were 11 primary and 26 revision total hip arthroplasty. There were 9 hips of AAOS-type I defect, 13 of type II and 15 of type III. Morselized bone grafting was used in 24 cases, bulk structural bone grafting in 6 cases and mixed bone grafting in 7 cases. Twenty-one patients used cementless prosthesis and 16 used cemented prosthesis. The average follow-up period was 53.7 months (6.5 to 130.5 months), the average preoperative Harris hip score was 42 +/- 8 with contrast to 87 +/- 5 of post-operation. Statistically significant difference was found according to t-test with P value less than 0.05. Major or complete healing of grafting bone was obtained at the latest follow-up. Acetabular bone defect during primary or revision total hip arthroplasty should be reconstructed according to its characteristics and severity. For relatively simple AAOS type I and type II cases, morselized or bulk structural bone grafting together with cementless prosthesis could achieve favorable initial stability, but for more severe AAOS type III cases, bulk structural bone grafting with accessory reinforcement hardware would be necessary. Though the early and mid-term results of the above strategies are satisfied, the long term outcome still require further study.

Revision With Impacted Bone Allografts and the Kerboull Cross Plate for Massive Bone Defect of the Acetabulum

We retrospectively reviewed 31 hips with massive bone defect because of aseptic loosening of the acetabulum treated with impacted bone allografts with the Kerboull-type acetabular device. Mean age at surgery was 67.9 years, and mean duration of follow-up was 6.3 years. Thickness of the bone graft was evaluated by postoperative radiography. Seven hips showed radiological failure associated with 6 breakages of the device, and 24 hips showed stability on follow-up radiographs. Of the 13 hips showing a bone graft thickness of greater than 20 mm on follow-up radiographs, 7 were classified as failure group. If an acetabular reinforcement device with a bone graft of more than 20 mm thickness is necessary, then a structural allograft should be considered in the weight-bearing area of the support ring in addition to the morselized bone graft.

Acetabular Revision with Impacted Morselized Cancellous Bone Graft and a Cemented Cup in Patients with Rheumatoid Arthritis

We previously reported our results at a minimum of three years after thirty-five revisions of total hip arthroplasty acetabular components in twenty-eight patients with rheumatoid arthritis. The revisions were performed with use of impacted morselized bone graft and a cemented cup. This update report presents the results at eight to nineteen years after the surgery, which, to our knowledge, is the longest follow-up available in the literature. No patient was lost to follow-up. Since our previous report, there were two additional cup failures due to aseptic loosening, at ten and sixteen years postoperatively. Kaplan-Meier analysis showed the probability of survival of the acetabular component at twelve years to be 80% (95% confidence interval, 65% to 95%) with removal of the cup for any reason as the end point and 85% (95% confidence interval, 71% to 99%) with aseptic loosening as the end point. Cup revisions performed with cement and use of impaction bone-grafting in patients with rheumatoid arthritis led to acceptable long-term prosthetic survival rates. This technique is attractive from a biological standpoint because of the possibility of maintaining acetabular bone stock.

Conversion of failed ankle arthroplasty to an arthrodesis

Arthrodesis of the ankle joint after a failed ankle prosthesis is most often demanding because of bone loss. The bone loss is also responsible for limb length discrepancy. Intramedullary nail fixation has been described to be successful for arthrodesis of the arthritic ankle joint. We report the use of the nail technique in combination with a morsellized bone graft in and around a cage to convert failed ankle prosthesis with bone loss into an arthrodesis. The advantages which were strived for include developing a more practical operative method with lower morbidity (no autograft), early mobilization and weight-bearing provided by the stability of the internal fixation and restoration of limb length.

The stability of impacted morsellized bone grafts in a metal cage under dynamic loaded conditions: an in vitro reconstruction of a segmental diaphyseal bone defect

Reconstructions of segmental diaphyseal bone defects with massive allografts are related to complications like nonunion and fractures. A reconstruction of these defects with a cage filled with an impacted morsellized bone graft could be an alternative. The bone graft in these cages should ideally be loaded to prevent resorption. Loading of morsellized bone grafts however can cause instability. The goal of this study was to assess the stability of an impacted morsellized bone graft in a cage under dynamic loaded conditions in an in vitro reconstruction of a segmental diaphyseal bone defect. The second goal was to assess the influence of cage type, washing of the graft and bone-cage fit. Two different cage types were filled with impacted morsellized bone graft. The grafts were used washed and unwashed and in variable bone-cage fit conditions. We recorded the bone graft deformation in the cage under dynamic loaded conditions. Stability appeared to be not very sensitive to the cage type and whether the bone chips were washed or not. However, quality of the fit of the cage with the bone segment was an important parameter and should be optimized during surgery. Morsellized impacted bone graft in a cage is stable in dynamic loaded conditions in an in vitro reconstruction of a segmental diaphyseal bone defect. We believe that this method of reconstruction is a promising alternative for the reconstruction of large diaphyseal bone defects and should be tested relative to its biological merits in animal experiments.

Is an Impacted Morselized Graft in a Cage an Alternative for Reconstructing Segmental Diaphyseal Defects?

Large diaphyseal bone defects often are reconstructed with large structural allografts but these are prone to major complications. We therefore asked whether impacted morselized bone graft could be an alternative for a massive structural graft in reconstructing large diaphyseal bone defects. Defects in the femora of goats were reconstructed using a cage filled with firmly impacted morselized allograft or with a structural cortical autograft (n = 6 in both groups). All reconstructions were stabilized with an intramedullary nail. The goats were allowed full weightbearing. In all reconstructions, the grafts united radiographically. Mechanical torsion strength of the femur with the cage and structural cortical graft reconstructions were 66.6% and 60.3%, respectively, as compared with the contralateral femurs after 6 months. Histologically, the impacted morselized graft was replaced completely by new viable bone. In the structural graft group, a mixture of new and necrotic bone was present. Incorporation of the impacted graft into new viable bone suggests this type of reconstruction may be safer than reconstruction with a structural graft in which creeping substitution results in a mixture of viable and necrotic bone that can fracture. The data suggest that a cage filled with a loaded morselized graft could be an alternative for the massive cortical graft in reconstruction of large diaphyseal defects in an animal model.

Posterior Lumbar Interbody Fusion Using a Unilateral Single Cage and a Local Morselized Bone Graft in the Degenerative Lumbar Spine

BackgroundWe retrospectively evaluated the clinical and radiological outcomes of posterior lumbar interbody fusion (PLIF) with using a unilateral single cage and a local morselized bone graft.MethodsFifty three patients who underwent PLIF with a unilateral single cage filled with local morselized bone graft were enrolled in this study. The average follow-up duration was 31.1 months. The clinical outcomes were evaluated with using the visual analogue scale (VAS) at the pre-operative period, at 1 year post-operation and at the last follow-up, the Oswestry Disability Index, the Prolo scale and the Kim & Kim criteria at the last follow-up; the radiological outcomes were evaluated according to the change of bone bridging, the radiolucency, the instablity and the disc height.ResultsFor the clinical evaluation, the VAS pain index, the Oswestry Disability Index, the Prolo scale and the Kim & Kim criteria showed excellent outcomes. For the the radiological evaluation, 52 cases showed complete bone union at the last follow-up. Regarding the complications, only 1 patient had cage breakage during follow-up.ConclusionsPLIF using a unilateral single cage filled with a local morselized bone graft has the advantages of a shorter operation time, less blood loss and a shorter hospital stay, as compared with the PLIF using bilateral cages, for treating degenerative lumbar spine disease. This technique also provides excellent outcomes according to the clinical and radiological evaluation.

Constitutive Models for Constrained Compression of Unimpacted and Impacted Human Morselized Bone Grafts

Morselized corticocancellous bone (MCB) is widely used in revision surgery with and without impaction. In the current study material parameters for the nonlinear viscoelastic and plastic responses of impacted and unimpacted human MCBs were determined during constrained compression. These models may be useful in finite element analyses of surgical constructs involving impacted and unimpacted MCBs. MCB is impacted layer by layer in the femoral canal during revision surgery. The influence of different layers on the mechanical properties was therefore also examined by comparing the relaxation strength and elastic and plastic strains for bone pellets impacted in one and two layers during constrained compression of human MCB. The relaxation strength was found to increase significantly by 14% for two layer pellets compared to one layer pellets, and the plastic strains decreased significantly by 15%, while the elastic strains were similar.

Instrumented Posterior Lumbar Interbody Fusion in Adult Spondylolisthesis

It is unclear whether using artificial cages increases fusion rates compared with use of bone chips alone in posterior lumbar interbody fusion for patients with lumbar spondylolisthesis. We hypothesized artificial cages for posterior lumbar interbody fusion would provide better clinical and radiographic outcomes than bone chips alone. We assumed solid fusion would provide good clinical outcomes. We clinically and radiographically followed 34 patients with spondylolisthesis having posterior lumbar interbody fusion with mixed autogenous and allogeneic bone chips alone and 42 patients having posterior lumbar interbody fusion with implantation of artificial cages packed with morselized bone graft. Patients with the artificial cage had better functional improvement in the Oswestry disability index than those with bone chips alone, whereas pain score, patient satisfaction, and fusion rate were similar in the two groups. Postoperative disc height ratio, slip ratio, and segmental lordosis all decreased at final followup in the patients with bone chips alone but remained unchanged in the artificial cage group. The functional outcome correlated with radiographic fusion status. We conclude artificial cages provide better functional outcomes and radiographic improvement than bone chips alone in posterior lumbar interbody fusion for lumbar spondylolisthesis, although both techniques achieved comparable fusion rates. Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Treatment of thoracolumbar vertebrate fracture by transpedicular morselized bone grafting in vertebrae for spinal fusion and pedicle screw fixation

To enhance the fusion of graft bone in thoracolumbar vertebrae and minimize the postoperative loss of correction, short-segment pedicle screw fixation was reinforced with posterior morselized bone grafting in vertebrae for spinal fusion in patients with thoracolumbar vertebrate fractures. Seventy patients with thoracolumbar vertebrate fractures were treated by short-segment pedicle screw fixation and were randomly divided into two groups. Fractures in group A (n=20) were reinforced with posterior morselized bone grafting in vertebrae for spinal fusion, while patients group B (n=50) did not receive the morselized bone grafting for bone fusion. The two groups were compared in terms of kyphotic deformity, anterior vertebral height, instrument failure and neurological functions after the treatment. Frankel grading system was used for the evaluation of neurological evaluation and Denis scoring scale was employed for pain assessment. The results showed that the kyphosis correction was achieved in both group A and group B (group A: 6.4 degree; group B: 5.4 degree)/ At the end of follow-up, kyphosis correction was maintained in group A but lost in group B (P=0.0001). Postoperatively, greater anterior height was achieved in group A than in group B (P<0.01). During follow-up study, anterior vertebral height was maintained only in Group A (P<0.001). Both group A and group B showed good Denis pain scores (P1 and P2) but group A outdid group B in terms of control of severe and constant pain (P4 and P5). By Frankel criteria, the changes in neurological functions in group A was better than those of group B (P<0.001). It is concluded that reinforcement of short-segment pedicle fixation with morselized bone grafting for the treatment of patients with thoracolumbar vertebrae fracture could achieve and maintain kyphosis correction, and it may also increase and maintain anterior vertebral height. Morselized bone grafting in vertebrae offers immediate spinal stability in patients with thoracolumbar vertebrate fractures, decreases the instrument failure and provides better postoperative pain control than without the morselized bone grafting.

One-Stage Revision of Infected Total Hip Arthroplasty with Bone Graft

There are many different opinions in the literature regarding the best procedure for revision of infected hip arthroplasty and hence in achieving long-term stabilization of a new implant. Thirty-two patients with 32 loose and infected total hip arthroplasties underwent revision with a bone graft in a 1-stage procedure. The bone graft was used in the acetabulum and femur in 25 patients, in the acetabulum alone in 4 patients and in the femur alone in 3 patients. A metal mesh was necessary in 15 patients to contain the morselized bone graft. At the time of surgical revision, 9 patients had a draining sinus, 6 had a closed sinus, and 17 had never had sinuses in the surgical wound. Antibiotic therapy was administered intravenously and orally for 6 months. Mean follow-up was 103 months (range, 63-183 months), and infection recurred in 2 (6.2%) cases. Further studies are necessary, and continuation of this method is justified.

Local treatment of cancellous bone grafts with BMP-7 and zoledronate increases both bone formation and bone density. A bone chamber study in rats

Open Access This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the source is credited. DOI 10.3109/17453674.2011.566138 Background and purpose The remodeling of morselized bone grafts in revision surgery can be enhanced by an anabolic substance such as a bone morphogenetic protein (BMP). On the other hand, BMPs boost catabolism and might cause a premature resorption, both of the graft and of the new-formed bone. Bisphosphonates inactivate osteoclasts and can be used to control the resorption. We studied a combination of both drugs as a local admix to a cancellous allograft. Methods Cancellous bone allografts were harvested and freeze-dried. Either saline, BMP-7, the bisphosphonate zoledronate, or a combination of BMP-7 and zoledronate were added in solution. The grafts were placed in bone conduction chambers and implanted in the proximal tibia of 34 rats. The grafts were harvested after 6 weeks and evaluated by histomorphometry. Results Bone volume/total volume (BV/TV) was 50% in the grafts treated with the combination of BMP-7 and zoledronate and 16% in the saline controls (p < 0.001). In the zoledronate group BV/TV was 56%, and in the BMP group it was 14%. The ingrowth distance of new bone into the graft was 3.5 mm for the combination of BMP-7 and zoledronate and 2.6 mm in the saline control (p = 0.002). The net amount of retained remodeled bone was more than 4 times higher when BMP-7 and zoledronate were combined than in the controls. Interpretation An anabolic drug like BMP-7 can be combined with an anti-catabolic bisphosphonate as local bone graft adjunct, and the combination increases the amount of remaining bone after remodeling is complete.

Morselized bone grafting in revision arthroplasty of the knee: A retrospective analysis of 34 reconstructions after 2–9 years

Background and purpose Loosening of a total knee replacement may lead to loss of bone, requiring biological reconstruction at revision arthroplasty. Good results have been reported from revision arthroplasty of the hip using impaction bone grafting. We report our results of revision total knee arthroplasty using the same technique.Patients and methods We retrospectively analyzed 30 patients (involving 34 knees) with a mean age of 63 (34–81) years who, between 1994 and 2002, underwent revision arthroplasty of the knee using hinge or rotational knee prostheses (Link) and impaction bone grafting. The average follow-up was 4 (2–9) years and included a questionnaire, a clinical examination, and standardized radiographs.Results 25 patients were satisfied with their results. 10 patients reported no impairment in their activities of daily living attributed to their operation and did not need any walking support. In 5 patients, there were no clear radiographic signs of incorporation of the graft but that did not compromise the outcome. 5 other patients had complications due to aseptic loosening of their prostheses with radiographic failure of the graft, leading to a periprosthetic fracture in 2 cases.Interpretation Our results with impaction bone grafting in knee revision arthroplasty appear to be similar to those obtained by the same technique in revision hip surgery.

Adjuvant therapies of bone graft around non-cemented experimental orthopedic implants stereological methods and experiments in dogs

Revision arthroplasty is a challenging aspect of the otherwise quite successful area of joint replacement surgery. The instable interaction between implant and host bone has often initiated a destructive process of inflammation and osteolysis, rendering the revision site sclerotic and with insufficient bone stock. One way of dealing with this is to build up a bed of tightly packed morselized bone graft to support the revision implant in a procedure often referred to as impaction grafting. Fresh frozen morselized femoral head allograft is the gold standard material for impaction grafting of the large defects usually involved in revision arthroplasty. The clinical outcome does not match that of primary arthroplasties. Implant subsidence is greater, implant survival shorter, and the bone graft is often not incorporated into living bone. The studies constituting this thesis have investigated ways of improving early implant fixation and bone graft incorporation. All studies used the same experimental canine model of early fixation and osseointegration of uncemented implant components inserted into a bed of impacted bone graft. Study I compared bone grafted implants where the morselized allograft was used alone or had been added rhBMP-2, the bisphosphonate pamidronate or a combination of the two. The main object was to see wether the previously observed growth factor related accelerated allograft resorption could be counteracted by the addition of an anti-catabolic drug. The study also compared HA-coated and non-coated porous Ti implants. The untreated control implants had better mechanical fixation than all other treatment groups. RhBMP-2 raised the total metabolic turnover of bone within the allograft with a net negative result on implant fixation. Pamidronate virtually blocked bone metabolism, also when combined with rhBMP-2. The HA-coated implants had more than twice as good mechanical fixation and improved osseointegration compared to the corresponding Ti implants. Study II investigated the addition of a bovine bone matrix lyophilisate (Colloss) to the allograft in three different doses. The main object was to see, whether the addition of a biological delivery device of low-dose osteogenic growth factors could provide a sufficient signal to increase the bioactivity of the bone graft without also yielding mechanical instability through increased allograft resorption. Allograft resorption increased with increased signal dose, but not to the extent that it affected implant fixation negatively at the observational time point. Mechanical implant fixation was doubled, and implant osseointegration and graft incorporation were improved. Study III compared a beta-TCP ceramic bone graft substitute (Ossaplast) with and without an osteogenic signal (Colloss E) to morselized allograft with and without the same signal. The object was to investigate, whether the addition of an osteogenic stimulus to a bio ceramic could replace biological allograft bone. The addition of an osteogenic signal improved early osseointegration of implants grafted with beta-TCP granules and increased their mechanical implant fixation to a level comparable to the allografted implants. All studies I-III confirmed that the topical addition of an osteogenic signal could increase implant osseointegration and the formation of new bone within a grafted defect. Another striking observation was the near-complete absence of fibrous tissue in the treated groups. The osseointegration of ceramic bone grafts improves when both the osteoconductive as well as the osteogenic components of bone are substituted. The effect on implant fixation of devices and pharmaceuticals that influence bone metabolism can be difficult to predict, as shown in study I. There seems to be a therapeutic window for these substances. This must be further explored prior to clinical use, as the adverse effects of overdosing bone anabolic and anti-catabolic substances can be detrimental.

Primary Total Hip Arthroplasty in Protrusio Acetabuli Using Impacted Morsellized Bone Grafting and Cementless Cups: A Medium-Term Radiographic Review

Thirty primary total hip arthroplasties were performed for protrusio acetabuli in 23 patients (mean age, 46 years) using impacted autologous bone grafting and a cementless porous-coated hemispheric cup without the use of metal cages or rings. At 2 to 10 years' follow-up (mean, 4.2 years), there was satisfactory radiographic evidence of consolidation of the graft in all cases. All acetabular components were considered to be stable with no instance of graft resorption. Clinical results were considered as excellent in 14 hips, good in 13 hips, fair in 2 hips, and poor in 1 hip. For younger patients with protrusio acetabuli, use of an uncemented porous-coated hemispheric cup with peripheral press-fit fixation and restoration of bone stock with impacted autologous bone grafting reflect a technically straightforward procedure that appears to give satisfactory medium-term results.

Reprise des descellements acétabulaires aseptiques par cupule non cimentée, vissée et allogreffe morcelée impactée

Purpose of the study Impaction grafting can be used in cementless fixation with morsellized bone, bone graft, and hemispherical cup. The first goal of impaction grafting in revision of total hip arthroplasty is to transform segmental defects into cavitary defects and obtain a full compaction of the graft in order to restore the bone stock. The second goal is to achieve primary stability of the cup. The third goal is to restore the hip center of rotation with a cup anatomically located in the acetabulum. The aim of our study was to evaluate the results of a surgical technique with impacted morsellized bone graft and a cementless press-fit cup for the revision with defect type III according to the AAOS classification. Material and methods We performed a retrospective study including 34 hip reconstructions during revision of acetabular aseptic loosening with type III AAOS acetabular defects. All the revisions were performed in the same center by two senior surgeons. Mean age at surgery was 58 years. There were 23 women and 11 men. All reconstructions were performed with a cementless cup and a morsellized impacted bone graft. The analysis of the acetabular defects was done preoperatively according to the AAOS classification. We analyzed postoperatively and at follow-up: position and stability of the acetabular cup, restoration of the hip center and graft integration. Results Mean follow-up was 6.6 years (range 3-13 years). Complications included three dislocations, two trochaanteric nonunions. Two acetabular components were revised for septic loosening. According to the Kaplan-Meier survival curves, with endpoint criteria defined as acetabular cup removal, survival was 91.3% at 10 years (95CI: 86.3-96.3). The preoperative Harris hip score was 53 points (range 26-86) and at last follow-up 94 (47-100). Concerning the subjective clinical outcome, 96% of patients were satisfied or very satisfied at last follow-up. 100% of cups were considered stable at follow-up and bone integration was good in 100%. The center of rotation was located in anatomic position mediolaterally in 66% and in the craniopodal plane in 44%. Discussion Restoration of bone stock is one of the main goals during hip reconstruction after aseptic loosening. Clinical experience in our series has shown the reliability of the impacted morsellized bone graft allowing relocation of the center of rotation and good cup stability. Biological fixation of the cup and graft integration seems good at mid-term follow-up. The cup that we used in our series combined the advantages of a press-fit cup and those of a reinforcement ring. The combination of this type of cup with morsellized bone graft seems to be a reliable solution for restoring bone stock, relocating the hip center, and stabilizing the cup in revision total hip arthroplasty with type III acetabular defect according to the AAOS classification.

Morsellized Allograft and Acetabular Reconstruction Cage: Follow-up of 2 to 9 years

We report the outcome of 32 patients who underwent total hip replacement (THR) augmented with morsellized fresh frozen femoral head allografts and acetabular reconstruction cages. Nine patients underwent primary THR and 23 patients underwent revision THR. Follow-up ranged from two to 9 years. Two most common indications for the procedures as reported in literature were rheumatoid arthritis and aseptic loosening of the hip. All but one patient achieved good outcome with radiographs showing full incorporation of bone grafts and no evidence of loosening of the implants. Morsellized bone grafting used with acetabular reinforcement devices is valuable for addressing severe acetabular deficiencies.