The Merete BioBall system in hip revision surgery: A systematic review

Mix and Match Use of Revision Universal Head-Neck Adapters in Hip Arthroplasty: A Complications and Survival Analysis of 306 Cases

BACKGROUND

Outcomes and safety of "mix and match" in total hip arthroplasty (THA) using universal head-neck adapters (UHNA) are a matter of ongoing discussion and concern due to legal affairs. This study aimed at analyzing the "mix and match" use of UHNA and evaluating complication and reoperation rates, possible risk factors, and the implant's survival.

METHODS

A total of 306 patients treated with THA (94.1% revisions) using a UHNA at our institution between 2006 and 2022 were identified and included. Diagnoses, comorbidities, implants, and UHNA specifications were retrospectively recorded. Outcomes, complications, and survival analyses were evaluated, taking into account various possible risk factors.

RESULTS

There were 19.9% of the 306 included cases (58.5% women; median age 74 years; median follow-up 57 months) that had at least 1 complication. There were 43 patients (14.1%) who had to receive ≥1 rerevision surgery. The most common complication was postoperative recurrent dislocation (n = 27, 8.8%). There was one case of a prosthetic stem-neck fracture that was registered. Statistically significant risk factors for postoperative recurrent dislocations and postoperative aseptic loosening were, respectively, dislocation as an indication for UHNA implantation (P < .001) and oversized neck lengths (≥2XL; P = .004). The overall revision-free survival was 92% after 1 year and 82% at ten years. Statistically significant better survival rates were registered in patients ≥60 years old, who had fewer comorbidities (<2), and normal neck lengths (S to XL).

CONCLUSIONS

The results of this study underline the overall safety of UHNA use in THA through "mix and match." Only one case of a stem-neck fracture was identified. The highlighted risk factors for failure must be kept in mind during the decision-making process with patients.

Contribution of the BioballTM head-neck adapter to the restoration of femoral offset in hip revision arthroplasty with retention of a well-fixed cup and stem

PURPOSE

Failure to restore the femoral offset of the native hip is a potential cause of dysfunctional hip arthroplasty. The aim of this study was to report our experience of using a modular head-neck adapter in revision THA, specifically analyzing its usefulness as a tool to correct a slightly diminished femoral offset.

MATERIALS AND METHODS

This was a retrospective single-center study including all hip revisions performed at our institution from January 2017 to March 2022 where the BioBallTM head-neck metal adapter was used. The preoperative and one year follow-up modified Merle d'Aubigné hip score was used to evaluate functional outcomes.

RESULTS

Of a total of 34 cases included for revision, the head-neck adapter system was used specifically in six patients (17.6%) to increase femoral offset, retaining both the acetabular and femoral components. In this subgroup of patients, mean offset decrease after primary THA was 6.6 mm (4.0-9.1), equivalent to a mean 16.3% femoral offset reduction. The median modified Merle d'Aubigné score went from 13.3 preoperatively to 16.2 at one year follow-up.

CONCLUSION

The use of a head-neck adapter is a safe and reliable procedure that may allow the surgeon to easily correct a slightly diminished femoral offset in a dysfunctional THA without the need to revise well-fixed prosthetic components.

A Modular Head-Neck Adapter System and Ceramic Heads in Revision Hip Arthroplasty: A Registry Study on 354 Implants

BACKGROUND

Five- to 10-year outcomes of a modular head-neck adapter system with ceramic heads in revision hip arthroplasty on large populations are still lacking. A registry study about modular adapter system with Delta ceramic head in revisions was designed, aiming to assess (1) the survival rates of the device, (2) the reasons for re-revisions of the device, and (3) a comparison to factory assembled titanium sleeve and Delta head cohort in revision hips.

METHODS

Using a regional arthroplasty registry, we investigated the modular adapter system with a ceramic head in revision hips. Demographics, implant features, and reasons for revision were recorded. Survival rates and reasons for re-revision were assessed. The modular adapter system with the ceramic ball was compared to a factory-assembled ceramic titanium-sleeved head in revisions, acting as a control group. There were 354 revisions included at a mean follow-up of 5 years (range, 0 to 13).

RESULTS

The 5- and 7-year survival rates were 87.9% and 86.9%, respectively. Dislocations (2.8%) and cup aseptic loosening (4.2%) were the 2 most frequent reasons for re-revision. No breakage of the adapter system or the ceramic head occurred. A femoral neck failed (0.3%). No implant features, offset (P = .088) or skirted (P = .870) tapers, impacted on failures. No differences between the 2 cohorts were found regarding survival rates (P = .696) and reasons for re-revision (dislocations, P = .983; cup aseptic loosening, P = .296).

CONCLUSION

The modular head neck adapter system with a ceramic head seems to be a valid option in revisions at 5 and 7 years, without additional risk of implant breakage in this registry.

Revision Hip Arthroplasty Using a Modular Head-Neck Adapter System and a Ceramic Head: 5-Year Clinical and Radiographic Outcomes

INTRODUCTION

A modular head-neck adapter system may help surgeons restore the proximal hip biomechanics in revision hip arthroplasty. However, the clinical and radiographic 5-year outcomes of the system are still scarcely reported. The aim of this study is the assessment of (1) complications and survival rates, (2) clinical and (3) radiological outcomes of the modular head-neck adapter system with a ceramic head in revision hip arthroplasty at 5 years.

METHODS

32 revision hip arthroplasties using a modular head-neck adapter system and a ceramic head were retrospectively recorded. Preoperative demographic and implant features were collected. Clinical and radiographic outcomes, failures and reasons for re-revisions were recorded at the last follow-up.

RESULTS

A mean follow-up of 59.8 ± 26 months was achieved. The survival rate was 90.6% at 5 years. Post-operative complications occurred in nine cases (28.1%): two dislocations (6.2%), one aseptic cup loosening (3.1%) requiring re-revision, one (3.1%) persistent pelvic pseudotumor requiring embolization. No mechanical failures of the adapter or ceramic head occurred. The mean post-operative HHS score was 84.4 points. Thirteen cases (40.6%) showed optimal radiographic cup osseointegration, and 17 hips (53.1%) showed valid stem osseointegration. The mean post-operative femoral offset was 48.84 mm, larger than the contralateral side (p = 0.02). The post-operative lateralization of the hip joint was 38.09 mm, close to the contralateral side (p = 0.4).

CONCLUSIONS

In revisions, the modular head-neck adapter system with ceramic head provided good clinical outcomes and acceptable radiographic reconstruction of hip biomechanics, with a survival rate of 87.9% at 5 years.

Clinical outcome of Bioball universal adapter in revision hip arthroplasty

Background

Removal of a well-fixed uncemented femoral component in revision hip arthroplasty is challenging. A modular head-neck adapter provides an option to optimise the femoral offset and anteversion, avoiding the need for femoral stem revision.

Aim

To present the clinical results following revision arthroplasty with the Bioball head-neck adapter in the elderly American Society of Anaesthesiologists (ASA) Grade II, III & IV patients.

Materials and methods

A retrospective review of our database was performed, and all patients classed as ASA grades II, III, & IV treated with the Bioball Universal Adapter (BUA) for 10 years were included. The indication for revision, stem retention, type of adapter, and head size were identified. Patients were contacted by a research nurse to assess the Forgotten Joint Score (FJS), the Oxford Hip Score (OHS), and any symptoms of instability at a minimum of one year post revision surgery.

Results

Our study included 47 patients. 5 (10.6%) were ASA II, 19 (40.4%) were ASA III and 23 (49%) were ASA IV. The mean age was 74 years. The mean follow up was 52 months ± 28.4 SD. The median FJS was 86 ± 11.6 SD. The median OHS was 43 ± 6.2 SD. One patient (2.1%) developed recurrent dislocation following lumbar spinal fusion. None of the other patients experienced instability. The survival rate for the adapter was 98%.

Conclusion

The BUA gives good clinical outcomes with very low post revision instability. It is a valuable option for the elderly because it avoids the morbidity and risks associated with the removal of a well-fixed femoral stem.

Level of Evidence

Level IV.

Outcome of revision surgery in recurrent dislocation of primary total hip arthroplasty

BACKGROUND

The cause of recurrent dislocation following primary total hip arthroplasty (THA) is multifactorial. A re-dislocation rate of up-to 34% following revision is reported. The aim of this study was to determine the re-dislocation rates following revision for recurrent THR dislocation.

METHODOLOGY

Patients who underwent revision for recurrent dislocation between January 2008 and January 2015 were identified. We identified the date and type of primary implant, overall number and reasons for dislocation, revision implant details and complication data.

RESULTS

Over an 8-year period, 24 patients underwent revision. The median age was 77 (68-85) years, median time to first dislocation was 78 (23-160) months and median number of dislocations was 3 (2-4) with a mean follow-up of 18 months. Socket Mal-Orientation (10) and Abductor deficiency (5) were the main causes of recurrent dislocation. 21 patients (88%) underwent revision of both components, 1 patient underwent isolated cup revision and 2 patients had revision of acetabular component with insertion of a BioBall. There were no dislocations within 90 days of revision surgery. 4 patients had late dislocations (3 recurrent, 1 isolated). There was no significant increase risk of dislocation after revision surgery in the neck of femur group (p = 0.467).

CONCLUSIONS

We report favourable outcomes for revision of both components for recurrent dislocation with no dislocations within 90 days. The overall late dislocation rate was 16.7%, however, these patients have settled following closed reduction. Due to its multifactorial aetiology, both component revision can be considered in this patient population.

"Off-label" Usage of an Oxidized Zirconium Femoral Head in Revision of a Total Hip Arthroplasty with Mechanically Assisted Crevice Corrosion and a Legacy Taper

We present a case of a 72-year-old male with a history of a late 1980s metal-on-polyethylene total hip arthroplasty who presented with unilateral leg vascular compromise, joint pain, and stiffness and subsequently underwent revision for adverse local tissue reaction secondary to mechanically assisted crevice corrosion. His stable and extensively porous coated femoral implant had a legacy taper with no currently manufactured option for a non–Co-alloy femoral head. After shared decision-making with the patient, we opted to use an oxidized zirconium femoral head from another manufacturer with a similar taper during his revision surgery and documented that his vascular compromise resolved and his serum Co was undetectable 3 years after the revision.

Pushing Ceramic-on-Ceramic in the most extreme wear conditions: A hip simulator study

BACKGROUND

Hip revision surgery for fractured ceramic components may represent the worst-case wear scenario due to the high risks of recurrent dislocations, instability, and third body wear. The ideal bearing choice for the new prosthetic articulation is still subject of debate, while alumina matrix composite (AMC) articulations offer theoretical superior performances; the present work was designed to test the wear behaviour of ceramic on ceramic articulations (liner and head) in a worst-case scenario by adding ceramic third-body particles to the test lubricant with combined walking and subluxation cycles in a hip joint simulator. Therefore, we performed an in vitro study aiming to assess how does AMC articulation perform with 1) third-body particles added to the test environment and 2) under subluxation stresses.

HYPOTHESIS

We hypothesised that AMC articulations offer superior performances in such worst conditions.

MATERIALS AND METHODS

A hip simulator test was designed to analyse how AMC articulation performs with third-body particles added to the test environment and under subluxation stresses. Two different load patterns including level walking and subluxation of the ceramic liner were applied. The test fluid lubricant was contaminated by adding coarse ceramic particles during the first 2 million cycles and fine ceramic particles from 2 to 4 million cycles. Group 1 consisted of an alumina matrix composite articulation (liner and head); group 2 consisted of an alumina liner and an alumina matrix composite head. A control group consisting of an alumina ceramic liner articulated against an alumina matrix composite head was provided and only axially loaded. The liners of groups 1 and 2 were tested at an in vivo angle of 45° in the medial lateral plane (inclinationangle), which corresponds to an angle L=30° relative to the ISO standard fixated position used for in vitro testing. All mass measurements were performed using a high precision balance (Sartorius BP211D). During each examination, images on dedicated location of the bearing surfaces were taken using a digital microscope.

RESULTS

Mean cumulative wear of 0.09mg per million cycles between 2 and 4 million cycles was detected in group 2, and this value was significantly lower (p=0.016) in comparison with the average value in group 1 (0.21mg per million cycle). This result can be explained in light of a possible transformation phase of zirconia in AMC liners, probably due to excessive stress during subluxation cycles. However, wear levels observed are close to the gravimetric measurement detection limit of the Sartorious Balance (about 0.1-0.2mg); therefore, wear can be considered negligible in all groups.

CONCLUSION

Our results confirm that AMC couplings perform very well even in the worst-case wear scenario. Since AMC articulations revealed 25% lower cumulative wear respect to AMC on cross linked polyethylene in same simulator setup, AMC articulations should be considered the bearing of choice in revision surgery in light of the high risk of recurrent dislocations, instability, and third body wear.

LEVEL OF EVIDENCE

III, prospective case-control study, in vitro.

No radiological and biological sign of trunnionosis with Large Diameter Head Ceramic Bearing Total Hip Arthroplasty after 5 years

BACKGROUND

Trunnionosis of large diameter (LDH) metal-on-metal total hip arthroplasty (THA) was linked to high systemic chromium (Cr) and cobalt (Co) ion levels and local adverse reactions to metal debris (ARMD). The safety of CoC LDH THA is not yet available at mid-term. Measuring whole blood Ti level of ceramic on ceramic (CoC) LDH THA with a titanium (Ti) stem is an indirect way to assess the performance of its head-neck taper modular junction. Therefore, we wanted to determine: (1) if the whole blood Ti ion levels in patients with LDH CoC THA after a minimum of 5 years of implantation is within the expected values for similar well performing Ti THA, (2) if Ti level scientifically increases over time, which would suggest the presence of a progressive modular head/neck junction wear process, (3) if clinical or radiographical manifestations of implant dysfunction are present?

HYPOTHESIS

Ti blood levels of LDH CoC THA will indirectly reflect the expected levels due to passive corrosion of the implants and will be stable over time.

PATIENTS AND METHODS

We report the whole blood Ti, Cr, and Co levels at 5years minimum for 57 patients with unilateral primary LDH CoC THA with head sizes ranging from 36 to 48mm using Ti stem and acetabular component. To compare Ti ion levels modification over time, in 25 patients were a previous measurement (1-3years) was available, we compared it to their last follow-up results (>5 years). Mean Ti level in well performing Ti THAs is recognized to be around 2.0 ug/L. Although, there are no universally accepted Ti levels associated with problematic implant, we used safety threshold of 10 ug/L. Clinical and radiological outcomes were recorded at last follow-up.

RESULTS

At 79 months mean follow-up, all mean Ti levels were 1.9μg/L (min 1.2, max 4.4) and all subject had values below the safety threshold of 10ug/L. In the subgroup of 25 cases with a previous measurement, there was a decrease in mean Ti levels between 20 months and 78 months follow-up (2.2μg/L (1.6-3.9) versus 2.0μg/L (1.4-2.8), p=0.007). No statistically significant relation was observed between Ti level at last FU and bearing diameter (rho=0.046, p=0.0734) or the presence or absence of a Ti adaptor sleeve (p=0.454): 1.94ug/L (min 1.20, max 2.80) versus 1.90ug/L (min 1.20, max 4.40). At last follow up, no patients presented osteolysis signs on radiographs, clinical signs of ARMD or were reoperated. Most patients had excellent clinical with 98% of them reporting minor (29%) or no functional limitation (69%) and 44% perceive their THA as a natural hip joint. However, 3/57patients (5%) temporarily experienced hip squeaking and 18/57 (31%) reported clicking sound.

CONCLUSION

With the tested LDH CoC THA, Ti levels were low and related the uneventful and unavoidable passive corrosion of implant surfaces. Mid-term measurement of Ti in subjects with LDH CoC did not reveal any indirect signs of trunnionosis, which should already be observable by this time.

LEVEL OF EVIDENCE

IV, retrospective study.

Catastrophic failure of femoral stem modular junction when combined with metal-on-metal bearing in comparison to ceramic-on-ceramic: A retrospective cohort study

BACKGROUND

Metal ion release from total hip arthroplasty's (THA) metal-on-metal (MoM) bearing surfaces or head-neck modular junction (trunnionosis) has been identified as a major cause of adverse reaction to metal debris (ARMD). No study has compared the effects of these bearing couples when combined with modular neck femoral stems (MNFS) (i.e. did a modular CoCr have a higher effect than large MoM bearings on whole blood ion concentrations and ARMD). Therefore we did a retrospective comparative analysis of prospectively collected data aiming to: (1) assess the difference in metal ion release between a group of MoM and CoC bearings implanted with a non-cemented MNFS; (2) compare the ARMD and the related revision rates between the two bearing types; (3) compare the patients' HOOS and Harris Hip scores.

HYPOTHESIS

Metal ion levels and complications rate will be higher in MoM group.

METHODS

Thirty hips received the same short MNFS with modular CoCr. Seventeen had CoC bearing (16=36mm) and 13 large diameter head (LDH) MoM bearing (mean=50mm, 44-54mm) Both groups had whole blood Cobalt (Co) and Chromium (Cr) concentrations measurements at last follow up or before revision surgery (if any) and were compared to 41 control individuals without implants. ARMD, revision rates and other complications were censed. Functional outcome differences between operative groups were assessed with HOOS and Harris Hip scores.

RESULTS

Mean whole blood Co and Cr were 1.9μg/L (0.1-10.6 min-max) and 1.2μg/L (0.2-4.6 min-max) in the CoC group and 12.7μg/L (2.5-40.7 min-max) and 8.2μg/L (2.8-40.6 min-max) for MoM group. Controls presented whole blood Co and Cr levels of 0.2μg/L (0.04-0.2 min-max) and 0.6μg/L (0.1-0.7 min-max) respectively. CoC had significantly higher whole blood metal ion concentrations than controls, while MoM had significantly higher concentrations than both (p<0.001). MoM had a 9/13 (69%) revision rate due to ARMD (with stem-neck junction corrosion and wear were present in all cases) while the CoC had none. Functional scores at last follow up did not statistically differ between groups (Harris: CoC=94.1±8.4 vs MoM 91.8±14.8 (p=0.22) and CoC HOOS 90.2±10.7 vs 75.6±21.7 (p=0.08)).

CONCLUSION

In our study, MNFS with CoCr modular neck released metal ion systemically, as shown in CoC THAs, but when combined with MoM LDH bearings, that elevation was significantly higher. In MNFS MoM, these high metal ion levels translated into a dramatic ARMD related revision rate where stem-neck junction corrosion and wear were present in all cases. More research is required to understand the effects of MoM bearing on neck-stem junctions, and its mechanisms of corrosion.

LEVEL OF EVIDENCE

III; retrospective comparative study.

Retrospective multi-centre study on head adapters in partial revision hip arthroplasty

BACKGROUND

Instability and dislocation after total hip arthroplasty (THA) is a common reason for revision surgery. THA head-neck adapters promise the reconstruction of optimal femoral offset and leg length in revision THA (rTHA) while retaining stable implants. The aim of this retrospective multi-centre study is to report on the results achieved with the use of head adapters in partial rTHA, to avoid the instability of the implant.

METHODS

55 cases of partial rTHA performed between February 2015 and April 2017 in 3 different hospitals using the Bioball Head Adapter (BHA) (Bioball Merete, Medical GmbH, Berlin, Germany) were retrospectively recorded. All patients were evaluated from a radiological point of view at an average follow-up of 3.5 years. Failure was defined as re-revision surgery for any cause as well as a subjective feeling of instability of the joint.

RESULTS

One failure was registered in an extreme case and radiological findings show no suggestive signs of radiolucencies or loosening and therefore all implants have been considered stable.

CONCLUSIONS

Despite some limitations of this retrospective study and according to the relevant literature, our data confirms that BHA is a safe system that allows the flexibility to restore femoral offset and version, to adjust leg length, to minimise instability, to avoid unnecessary removal of otherwise well-fixed components thus improving tribology and reducing the risk of taper junction issues without major complications in partial rTHA.