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Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_16 | Pages 42 - 42
19 Aug 2024
de Graeff JJ Kowalska J van der Pas SL van Leeuwen N Willigenburg NW Neve WC de Vries LMA Schreurs BW Nelissen RGHH van Steenbergen LN Poolman R
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Controversy persists over whether cemented or uncemented fixation is more effective in reducing revision and mortality risks following primary total hip arthroplasty (THA). Despite a shift towards uncemented THA in Europe, Australia, and the US, no consensus exists on superior outcomes. This ambiguity in evidence from randomized controlled trials (RCTs) and observational studies necessitates advanced research methodologies to derive more definitive conclusions.

This study investigates the causal impact of THA fixation type on 2-year and 5-year revision rates, along with 90-day mortality, utilizing a regression discontinuity (RD) design in scenarios where fixation choice is guided by patient age.

Employing data from the Dutch Arthroplasty Register, we conducted a cohort study on primary THAs for osteoarthritis from 2007 to 2019. A “fuzzy” RD design was executed to compute the Local Average Treatment Effect for subjects around the age-based selection threshold for fixation type. The main outcome of interest was the revision rate at 2 years post-operation.

Analysis for the 2-year revision endpoint, covering any cause, included 2,344 females and 1,671 males across 5 hospitals each, with no significant variation in revision rates observed. For the 5-year mark, 1,058 females in 3 hospitals and 214 males in 1 hospital were examined, similarly showing no significant differences. Mortality within 90 days post-operation was also investigated in 5 female and 7 male cohorts, with 2,180 and 2,145 surgeries respectively, yielding no substantial disparities.

In conclusion, the RD analysis revealed no notable differences in revision rates at 2 and 5 years or in early mortality based on the fixation method used in THA. These outcomes suggest that the age-based preference for THA fixation may not influence the revision or mortality risk, underscoring the value of RD design in deriving causal insights from observational data.


Bone & Joint Open
Vol. 5, Issue 4 | Pages 260 - 268
1 Apr 2024
Broekhuis D Meurs WMH Kaptein BL Karunaratne S Carey Smith RL Sommerville S Boyle R Nelissen RGHH

Aims

Custom triflange acetabular components (CTACs) play an important role in reconstructive orthopaedic surgery, particularly in revision total hip arthroplasty (rTHA) and pelvic tumour resection procedures. Accurate CTAC positioning is essential to successful surgical outcomes. While prior studies have explored CTAC positioning in rTHA, research focusing on tumour cases and implant flange positioning precision remains limited. Additionally, the impact of intraoperative navigation on positioning accuracy warrants further investigation. This study assesses CTAC positioning accuracy in tumour resection and rTHA cases, focusing on the differences between preoperative planning and postoperative implant positions.

Methods

A multicentre observational cohort study in Australia between February 2017 and March 2021 included consecutive patients undergoing acetabular reconstruction with CTACs in rTHA (Paprosky 3A/3B defects) or tumour resection (including Enneking P2 peri-acetabular area). Of 103 eligible patients (104 hips), 34 patients (35 hips) were analyzed.


The Bone & Joint Journal
Vol. 106-B, Issue 2 | Pages 136 - 143
1 Feb 2024
van der Lelij TJN Marang-van de Mheen PJ Kaptein BL Koster LA Ljung P Nelissen RGHH Toksvig-Larsen S

Aims

The objective of this study was to compare the two-year migration and clinical outcomes of a new cementless hydroxyapatite (HA)-coated titanium acetabular shell with its previous version, which shared the same geometrical design but a different manufacturing process for applying the titanium surface.

Methods

Overall, 87 patients undergoing total hip arthroplasty (THA) were randomized to either a Trident II HA or Trident HA shell, each cementless with clusterholes and HA-coating. All components were used in combination with a cemented Exeter V40 femoral stem. Implant migration was measured using radiostereometric analysis (RSA), with radiographs taken within two days of surgery (baseline), and at three, 12, and 24 months postoperatively. Proximal acetabular component migration was the primary outcome measure. Clinical scores and patient-reported outcome measures (PROMs) were collected at each follow-up.


The Bone & Joint Journal
Vol. 104-B, Issue 2 | Pages 221 - 226
1 Feb 2022
Edwards NM Varnum C Nelissen RGHH Overgaard S Pedersen AB

Aims

The aim of this study was to examine whether socioeconomic status (SES) is associated with a higher risk of infections following total hip arthroplasty (THA) at 30 and 90 days.

Methods

We obtained individual-based information on SES markers (cohabitation, education, income, and savings) on 103,901 THA patients from Danish health registries between 1 January 1995 and 31 December 2017. The primary outcome measure was any hospital-treated infection (i.e. all infections). The secondary outcomes were further specified to specific hospital-treated infections (pneumonia, urinary tract infection, and periprosthetic joint infection). The primary timepoint was within 90 days. In addition, the outcomes were further evaluated within 30 days. We calculated the cumulative incidence, and used the pseudo-observation method and generalized linear regression to estimate adjusted risk ratios (RRs) with 95% confidence intervals (CIs) for each marker.


The Bone & Joint Journal
Vol. 98-B, Issue 10 | Pages 1333 - 1341
1 Oct 2016
van der Voort P Valstar ER Kaptein BL Fiocco M van der Heide HJL Nelissen RGHH

Aims

The widely used and well-proven Palacos R (a.k.a. Refobacin Palacos R) bone cement is no longer commercially available and was superseded by Refobacin bone cement R and Palacos R + G in 2005. However, the performance of these newly introduced bone cements have not been tested in a phased evidence-based manner, including roentgen stereophotogrammetric analysis (RSA).

Patients and Methods

In this blinded, randomised, clinical RSA study, the migration of the Stanmore femoral component was compared between Refobacin bone cement R and Palacos R + G in 62 consecutive total hip arthroplasties. The primary outcome measure was femoral component migration measured using RSA and secondary outcomes were Harris hip score (HHS), Hip disability and Osteoarthritis Outcome Score (HOOS), EuroQol 5D (EQ-5D) and Short Form 36 (SF-36).


The Bone & Joint Journal
Vol. 95-B, Issue 12 | Pages 1626 - 1631
1 Dec 2013
van der Weegen W Brakel K Horn RJ Hoekstra HJ Sijbesma T Pilot P Nelissen RGHH

The aim of this study was to establish the natural course of unrevised asymptomatic pseudotumours after metal-on-metal (MoM) hip resurfacing during a six- to 12-month follow-up period. We used repeated metal artefact reduction sequence (MARS)-magnetic resonance imaging (MRI), serum metal ion analysis and clinical examination to study 14 unrevised hips (mean patient age 52.7 years, 46 to 68, 5 female, 7 male) with a pseudotumour and 23 hips (mean patient age 52.8 years, 38 to 69, 7 female, 16 male) without a pseudotumour. The mean post-operative time to the first MARS-MRI scan was 4.3 years (2.2 to 8.3), and mean time between the first and second MARS-MRI scan was eight months (6 to 12). At the second MRI scan, the grade of severity of the pseudotumour had not changed in 35 hips. One new pseudotumour (Anderson C2 score, moderate) was observed, and one pseudotumour was downgraded from C2 (moderate) to C1 (mild). In general, the characteristics of the pseudotumours hardly changed.

Repeated MARS-MRI scans within one year in patients with asymptomatic pseudotumours after MoM hip resurfacing showed little or no variation. In 23 patients without pseudotumour, one new asymptomatic pseudotumour was detected.

This is the first longitudinal study on the natural history of pseudotumours using MARS-MRI scans in hip resurfacing, and mirrors recent results for 28 mm diameter MoM total hip replacement.

Cite this article: Bone Joint J 2013;95-B:1626–31.


Bone & Joint Research
Vol. 1, Issue 10 | Pages 258 - 262
1 Oct 2012
Keurentjes JC Fiocco M Schreurs BW Pijls BG Nouta KA Nelissen RGHH

Objectives

The Kaplan-Meier estimation is widely used in orthopedics to calculate the probability of revision surgery. Using data from a long-term follow-up study, we aimed to assess the amount of bias introduced by the Kaplan-Meier estimator in a competing risk setting.

Methods

We describe both the Kaplan-Meier estimator and the competing risk model, and explain why the competing risk model is a more appropriate approach to estimate the probability of revision surgery when patients die in a hip revision surgery cohort. In our study, a total of 62 acetabular revisions were performed. After a mean of 25 years, no patients were lost to follow-up, 13 patients had undergone revision surgery and 33 patients died of causes unrelated to their hip.


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 4 | Pages 460 - 466
1 Apr 2006
Keizer SB Kock NB Dijkstra PDS Taminiau AHM Nelissen RGHH

This retrospective study describes the long-term results of core decompression and placement of a non-vascularised bone graft in the management of avascular necrosis of the femoral head. We treated 80 hips in 65 patients, 18 by a cortical tibial autograft and 62 by a fibular allograft. The mean age of the patients was 36 years (sd 13.2). A total of 78 hips were available for evaluation of which pre-operatively six were Ficat-Arlet stage 0, three stage I, 31 stage IIA, 16 stage IIB, 13 stage III and nine stage IV.

A total of 34 hips (44%) were revised at a mean of four years (sd 3.8). Survivorship analysis using a clinical end-point showed a survival rate of 59% five years after surgery. We found a significant difference (p = 0.002) in survivorship, when using a clinical and radiological end-point, between the two grafts, in favour of the tibial autograft. We considered this difference to be the result of the better quality and increased volume of tibial bone compared with that from the trochanteric region used with the fibular allograft.

This is a relatively simple, extra-articular and reproducible procedure. In our view core decompression, removal of the necrotic tissue and packing of the cancellous grafts into the core track are vital parts of the procedure.