Multicup reconstruction technique for the management of severe protrusio acetabular defects

Background In revision hip arthroplasty, managing the large protrusio acetabular defects remains a challenge. The report described a novel technique which employs a trabecular metal revision shell as a super-augment to buttress the superior medial structure. Methods Between January 2015 and December 2018, the multicup reconstruction was performed in 21 patients with severe protrusio acetabular defects. The revision shell, plus two similar porous acetabular components was implanted into the initial shell to create a “multicup” construct. The functional outcomes were evaluated in terms of the Harris Hip Score. Acetabular loosening, restoration of hip center of rotation, and bone ingrowth etc., were radiographically assessed. The survival rate of the implants was also evaluated. Results A followup lasting a mean time of 31 months (range, 18–57 months) revealed that the average Harris Hip Score improved from preoperative 37.0 ± 7.1 to postoperative 76.4 ± 9.0. There were no revisions due to acetabular loosening. The horizontal offset increased by an average of 14 mm, and the vertical offset decreased by an average of 18 mm. Eighteen of the 21 patients (86 %) met at least 3 of 5 criteria associated with bone ingrowth. The survivorship free from re-revision for acetabular loosening after 2 years was 100 %. Conclusions The multicup reconstruction technique was a simplified re-revision procedure for managing the severe protrusio acetabular defects and could achieve a high survival rate. Level of evidence Therapeutic study, Level IVa.

Is there a problem with modular dual mobility acetabular components in revision total hip arthroplasty at mid-term follow-up?

Aims Modular dual mobility (MDM) acetabular components are often used with the aim of reducing the risk of dislocation in revision total hip arthroplasty (THA). There is, however, little information in the literature about its use in this context. The aim of this study, therefore, was to evaluate the outcomes in a cohort of patients in whom MDM components were used at revision THA, with a mean follow-up of more than five years. Methods Using the database of a single academic centre, 126 revision THAs in 117 patients using a single design of an MDM acetabular component were retrospectively reviewed. A total of 94 revision THAs in 88 patients with a mean follow-up of 5.5 years were included in the study. Survivorship was analyzed with the endpoints of dislocation, reoperation for dislocation, acetabular revision for aseptic loosening, and acetabular revision for any reason. The secondary endpoints were surgical complications and the radiological outcome. Results The overall rate of dislocation was 11%, with a six-year survival of 91%. Reoperation for dislocation was performed in seven patients (7%), with a six-year survival of 94%. The dislocations were early (at a mean of 33 days) in six patients, and late (at a mean of 4.3 years) in four patients. There were three intraprosthetic dissociations. An outer head diameter of ≥ 48 mm was associated with a lower risk of dislocation (p = 0.013). Lumbrosacral fusion was associated with increased dislocation (p = 0.004). Four revision THAs (4%) were further revised for aseptic acetabular loosening, and severe bone loss (Paprosky III) at the time of the initial revision was significantly associated with further revision for aseptic acetabular loosening (p = 0.008). Fourteen acetabular components (15%) were re-revised for infection, and a pre-revision diagnosis of reimplantation after periprosthetic joint infection (PJI) was associated with subsequent PJI (p < 0.001). Two THAs had visible metallic changes on the backside of the cobalt chromium liner. Conclusion When using this MDM component in revision THA, at a mean follow-up of 5.5 years, there was a higher rate of dislocation (11%) than previously reported. The size of the outer bearing was related to the risk of dislocation. There was a low rate of aseptic acetabular loosening. Longer follow-up of this MDM component and evaluation of other designs are warranted. Cite this article: Bone Joint J 2021;103-B(7 Supple B):66–72.

The long-term outcomes of modified Harrington procedure using antegrade pins for periacetabular metastasis and haematological diseases

Aims The aim of this study was to present the long-term surgical outcomes, complications, implant survival, and causes of implant failure in patients treated with the modified Harrington procedure using antegrade large diameter pins. Patients and Methods A cohort of 50 consecutive patients who underwent the modified Harrington procedure for periacetabular metastasis or haematological malignancy between January 1996 and April 2018 were studied. The median follow-up time for all survivors was 3.2 years (interquartile range 0.9 to 7.6 years). Results The five-year overall survival rate was 33% for all the patients. However, implant survival rates were 100% and 46% at five and ten years, respectively. Eight patients survived beyond five years. There was no immediate perioperative mortality or complications. A total of 15 late complications occurred in 11 patients (22%). Five patients (10%) required further surgery to treat complications. The most frequent complication was pin breakage without evidence of acetabular loosening (6%). Two patients (4%) underwent revision for aseptic loosening at 6.5 and 8.9 years after surgery. Ambulatory status and pain level were improved in 83% and 89%, respectively. Conclusion The modified Harrington procedure for acetabular destruction has low complication rates, good functional outcome, and improved pain relief in selected patients Cite this article: Bone Joint J 2019;101-B:1557–1562

Two-centre radiological survivorship of acetabular distraction technique for treatment of chronic pelvic discontinuity

AimsThe aim of this study was to examine the results of the acetabular distraction technique in achieving implantation of a stable construct, obtaining biological fixation, and producing healing of chronic pelvic discontinuity at revision total hip arthroplasty.Patients and MethodsWe identified 32 patients treated between 2006 and 2013 who underwent acetabular revision for a chronic pelvic discontinuity using acetabular distraction, and who were radiographically evaluated at a mean of 62 months (25 to 160). Of these patients, 28 (87.5%) were female. The mean age at the time of revision was 67 years (44 to 86). The patients represented a continuous series drawn from two institutions that adhered to an identical operative technique.ResultsOf the 32 patients, one patient required a revision for aseptic loosening, two patients had evidence of radiographic loosening but were not revised, and three patients had migration of the acetabular component into a more stable configuration. Radiographically, 22 (69%) of the cohort demonstrated healing of the discontinuity. The Kaplan–Meier construct survivorship was 83.3% when using revision for aseptic acetabular loosening as an endpoint. At the time when one patient failed due to aseptic loosening (at 7.4 years), there were a total of seven patients with a follow-up of seven years or longer who were at risk of failure.ConclusionThe acetabular distraction technique demonstrates encouraging radiographic outcomes, with healing of the discontinuity in over two-thirds of our series. This surgical technique permits biological fixation and intraoperative customization of the construct to be implanted based on the pattern of the bone loss identified following component removal. Cite this article: Bone Joint J 2018;100-B:909–14.

SURGICAL TREATMENT OF ISOLATED ASEPTIC ACETABULAR LOOSENING IN PATIENTS WITH STABLE FEMORAL COMPONENT

Background: Aseptic acetabular loosening currently occupies the 1st place in the structure of delayed complications after total hip arthroplasty. The basis of treatment is the replacement of a loosening cup and a pair of friction. The tactics of surgical treatment of the stable correctly oriented femoral component have not been determined, thoroughly which confirms the relevance of the study.Aims: Compare the effectiveness of total hip revision and isolated acetabular revision in patients with aseptic acetabular loosening and stable correctly oriented femoral component.Materials and methods: The study presented the results of surgical treatment performed in 44 patients (45 revisions) with isolated aseptic acetabular loosening and stable correctly oriented femoral component were presented, Patients were divided into two groups depending on the severity of surgery. The first group included 16 patients with a total revision due to irregular cone of the stem. The second group included 28 patients (29 revisions) with an isolated replacement of the unstable cup and a pair of friction.Results: In the 1st group, revision surgery was performed to replace both cup with the friction pair and stable correctly oriented stem which finally results in lower postoperative red blood counts (erythrocytes, hemoglobin, hematocrit), as well as higher intraoperative blood loss volume and longer duration of surgical intervention if compare to the 2nd group where the stable correctly oriented femoral component was not changed. Postoperative results assessed using Harris scales and Oxford Hip Score in the comparison group were at a higher level during the whole period of follow-up. A moderate coorelation between the severity of the revision intervention and its results was detected.Conclusions: Preservation of a stable correctly oriented stem allows to reduce the severity of the revision intervention which improves the results and shortens the period of patient rehabilitation.

Computer-assisted navigation in Birmingham hip resurfacing: A case report

Component malpositioning during Birmingham hip resurfacing increases the risk for component wear, metallosis, component loosening, and the likelihood of dislocation and revision surgery. Computer-assisted navigation can increase the accuracy to which components are placed, and the utilization of this technology in Birmingham hip resurfacing is increasing. The present report summarizes the accuracy of acetabular component positioning in a Birmingham hip resurfacing case utilizing navigation. Intraoperative C-arm fluoroscopy following the use of the navigation tool confirmed excellent seating, positioning, and stability of the acetabular component. In addition, post-operative antero-posterior radiographs confirmed device accuracy and revealed a stable joint with no evidence of acetabular loosening or femoral fracture. Computer-assisted navigation may therefore be an effective tool to improve the accuracy of component positioning during Birmingham hip resurfacing.

L5 Radiculopathy Secondary to Migration of a Revision Stemmed Acetabular Cup

Introduction Stemmed acetabular components are used in patients undergoing revision total hip arthroplasty in cases with major acetabular defects or pelvic discontinuity. Conflicting results relating to the survival of the component, and complication rates are reported in the literature. We present a case of L5 radiculopathy secondary to proximal migration of this device. Case description A 79-year-old man was admitted to our department in 2012 with increasing pain and paresthesias, initially diagnosed as left L5 radiculopathy. In 2002, he had undergone revision surgery due to aseptic loosening of the acetabular component with a stemmed acetabular cup. Radiological findings were severe osteolysis around the acetabular cup with proximal migration. MRI showed osteolysis involving the left L5/S1 facet joint and evidence of soft tissue in the left foramina encasing the L5 radicular nerve. Nerve conduction and electromyography studies revealed chronic L5 radiculopathy. Discussions This case report illustrates the importance of considering acetabular loosening in a patient presenting with radicular symptoms. If a stemmed acetabular cup is chosen for an acetabular reconstruction, careful surgical technique should be employed in order to achieve durable fixation. If the patient has pelvic discontinuity, other options of reconstruction have showed better outcomes in the literature.

High Proximal Migration in Cemented Acetabular Revisions Operated with Bone Impaction Grafting; 47 Revision Cups Followed with RSA for 17 Years

Background Bone impaction grafting is a biologically and mechanically appealing option in acetabular revision surgery, allowing restitution of the bone stock and restoration of the biomechanics. We analysed differences in proximal migration of the revision acetabular components when bone impaction grafting is used together with a cemented or an uncemented cup. Patients and Methods 43 patients (47 hips), revised due to acetabular loosening and judged to have less than 50% host bone-implant contact were included. The hips were randomised to either an uncemented (n = 20) or a cemented (n = 27) revision cup. Radiostereometry and radiography was performed postoperatively, at 3 and 6 months, 1, 2, 3, 5, 7, 10 and 13 and 17 years postoperatively. Clinical follow-up was performed at 1, 2 and 5 years postoperatively and thereafter at the same interval as in the radiographic follow-up. Results here were no differences in the base line demographic data between the 2 groups. At the last follow-up (17 years) 14 hips (10 cemented, 4 uncemented) had been re-revised due to loosening. 3 additional cups (1 uncemented and 2 cemented) were radiographically loose. There was a higher early proximal migration in the cemented cups. Discussion Cups operated on with cement showed a higher early migration measured with RSA and also a higher number of late revisions. The reason for this is not known, but factors such as inclusion of cases with severe bone defects, use of smaller bone chips and issues related to the impaction technique might have had various degrees of influence.