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Bone & Joint Research
Vol. 7, Issue 6 | Pages 388 - 396
1 Jun 2018
Langton DJ Sidaginamale RP Joyce TJ Bowsher JG Holland JP Deehan D Nargol AVF Natu S

Objectives

We have encountered patients who developed large joint fluid collections with massive elevations in chromium (Cr) and cobalt (Co) concentrations following metal-on-metal (MoM) hip arthroplasties. In some cases, retrieval analysis determined that these ion concentrations could not be explained simply by the wear rates of the components. We hypothesized that these effects may be associated with aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL).

Patients and Methods

We examined the influence of the ALVAL grade on synovial fluid Co and Cr concentrations following adjustment for patient and device variables, including volumetric wear rates. Initially restricting the analysis to include only patients with one MoM hip resurfacing device, we performed multiple regression analyses of prospectively collected data. We then repeated the same statistical approach using results from a larger cohort with different MoM designs, including total hip arthroplasties.


The Bone & Joint Journal
Vol. 99-B, Issue 10 | Pages 1304 - 1312
1 Oct 2017
Langton DJ Sidaginamale RP Joyce TJ Meek RD Bowsher JG Deehan D Nargol AVF Holland JP

Aims

We sought to determine whether cobalt-chromium alloy (CoCr) femoral stem tapers (trunnions) wear more than titanium (Ti) alloy stem tapers (trunnions) when used in a large diameter (LD) metal-on-metal (MoM) hip arthroplasty system.

Patients and Methods

We performed explant analysis using validated methodology to determine the volumetric material loss at the taper surfaces of explanted LD CoCr MoM hip arthroplasties used with either a Ti alloy (n = 28) or CoCr femoral stem (n = 21). Only 12/14 taper constructs with a rough male taper surface and a nominal included angle close to 5.666° were included. Multiple regression modelling was undertaken using taper angle, taper roughness, bearing diameter (horizontal lever arm) as independent variables. Material loss was mapped using a coordinate measuring machine, profilometry and scanning electron microscopy.


The Bone & Joint Journal
Vol. 98-B, Issue 7 | Pages 925 - 933
1 Jul 2016
Sidaginamale RP Joyce TJ Bowsher JG Lord JK Avery PJ Natu S Nargol AVF Langton DJ

Aims

We wished to investigate the influence of metal debris exposure on the subsequent immune response and resulting soft-tissue injury following metal-on-metal (MoM) hip arthroplasty. Some reports have suggested that debris generated from the head-neck taper junction is more destructive than equivalent doses from metal bearing surfaces.

Patients and Methods

We investigated the influence of the source and volume of metal debris on chromium (Cr) and cobalt (Co) concentrations in corresponding blood and hip synovial fluid samples and the observed agglomerated particle sizes in excised tissues using multiple regression analysis of prospectively collected data. A total of 199 explanted MoM hips (177 patients; 132 hips female) were analysed to determine rates of volumetric wear at the bearing surfaces and taper junctions.


Bone & Joint Research
Vol. 3, Issue 3 | Pages 60 - 68
1 Mar 2014
Langton DJ Sidaginamale RP Holland JP Deehan D Joyce TJ Nargol AVF Meek RD Lord JK

Objectives

Wear debris released from bearing surfaces has been shown to provoke negative immune responses in the recipient. Excessive wear has been linked to early failure of prostheses. Analysis using coordinate measuring machines (CMMs) can provide estimates of total volumetric material loss of explanted prostheses and can help to understand device failure. The accuracy of volumetric testing has been debated, with some investigators stating that only protocols involving hundreds of thousands of measurement points are sufficient. We looked to examine this assumption and to apply the findings to the clinical arena.

Methods

We examined the effects on the calculated material loss from a ceramic femoral head when different CMM scanning parameters were used. Calculated wear volumes were compared with gold standard gravimetric tests in a blinded study.


Bone & Joint Research
Vol. 2, Issue 5 | Pages 84 - 95
1 May 2013
Sidaginamale RP Joyce TJ Lord JK Jefferson R Blain PG Nargol AVF Langton DJ

Objectives

The aims of this piece of work were to: 1) record the background concentrations of blood chromium (Cr) and cobalt (Co) concentrations in a large group of subjects; 2) to compare blood/serum Cr and Co concentrations with retrieved metal-on-metal (MoM) hip resurfacings; 3) to examine the distribution of Co and Cr in the serum and whole blood of patients with MoM hip arthroplasties; and 4) to further understand the partitioning of metal ions between the serum and whole blood fractions.

Methods

A total of 3042 blood samples donated to the local transfusion centre were analysed to record Co and Cr concentrations. Also, 91 hip resurfacing devices from patients who had given pre-revision blood/serum samples for metal ion analysis underwent volumetric wear assessment using a coordinate measuring machine. Linear regression analysis was carried out and receiver operating characteristic curves were constructed to assess the reliability of metal ions to identify abnormally wearing implants. The relationship between serum and whole blood concentrations of Cr and Co in 1048 patients was analysed using Bland-Altman charts. This relationship was further investigated in an in vitro study during which human blood was spiked with trivalent and hexavalent Cr, the serum then separated and the fractions analysed.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXVI | Pages 23 - 23
1 Jun 2012
Sidaginamale RP Gunaratne M Fadero P Kotrba M
Full Access

Purpose

To evaluate the complications following percutaneous balloon kyphoplasty and assess the advantage of introducing eggshell technique.

Methods and Results

We performed 138 Balloon kyphoplasty procedures in 85 patients during august 2007 to march 2010. Data was collected and analyzed in all these cases. Gender distribution was 60 females and 25 males. Age distribution was 33 to 85 years, with an average age of 67.4 years. Indications of surgery were vertebral fractures due to osteoporosis in 81% of the procedures, trauma in 13% and malignancy in 6%. The most common vertebral levels of the kyphoplasty were at T12 in 32 procedures (23%) and L1 in 28 procedures (20%). Eggshell technique was introduced in 2009 where technical problems were encountered during cementing process.

All patients had reduced pain levels, which was assessed by visual analog score. The average length of hospital stay was 2.5 days. Complications were 9 (6.5%) cement leaks (all within one cm from the vertebral body) in procedures performed before the introduction of eggshell technique and no cement leak following the introduction of eggshell technique, 5 (3.6%) fresh fractures, 2 (1.4%) intra-operative fractures and 1 (0.73%) rupture of balloon. There were no complications of cord compression, motor deficit, infection, allergy to cement or pulmonary embolism noted. 30-day mortality rate was zero.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXVI | Pages 80 - 80
1 Jun 2012
Gunaratne M Sidaginamale RP Kotrba M
Full Access

Purpose

To elucidate the efficacy of carrying out additional vertebral biopsy procedure during percutaneous balloon kyphoplasty as a tool in determining malignant etiology.

Methods and Results

We performed 138 percutaneous balloon kyphoplasty procedures in 85 patients during august 2007 to march 2010. Gender distribution was 25 males and 60 females. Age distribution was 33 to 85 years, with an average age of 67.4 years.

The senior surgeon attempted vertebral biopsy during percutaneous balloon kyphoplasty procedure only when there was a clinical/operative suspicion of malignancy. We did not routinely biopsy all vertebrae, as this would mean additional procedure adding to the cost and operating time.

In 42 procedures vertebral biopsy was attempted, of which 5 samples were reported as insufficient specimen. 37 biopsies (88%) were successfully analyzed. 3 biopsies (8.1%) were positive for malignancy. There were no complications encountered in the cases where additional biopsy procedure was carried out.