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Bone & Joint Open
Vol. 2, Issue 11 | Pages 1004 - 1016
26 Nov 2021
Wight CM Whyne CM Bogoch ER Zdero R Chapman RM van Citters DW Walsh WR Schemitsch E

Aims

This study investigates head-neck taper corrosion with varying head size in a novel hip simulator instrumented to measure corrosion related electrical activity under torsional loads.

Methods

In all, six 28 mm and six 36 mm titanium stem-cobalt chrome head pairs with polyethylene sockets were tested in a novel instrumented hip simulator. Samples were tested using simulated gait data with incremental increasing loads to determine corrosion onset load and electrochemical activity. Half of each head size group were then cycled with simulated gait and the other half with gait compression only. Damage was measured by area and maximum linear wear depth.


Bone & Joint Research
Vol. 5, Issue 9 | Pages 370 - 378
1 Sep 2016
Munir S Oliver RA Zicat B Walter WL Walter WK Walsh WR

Objectives

This study aimed to characterise and qualitatively grade the severity of the corrosion particles released into the hip joint following taper corrosion.

Methods

The 26 cases examined were CoC/ABG Modular (n = 13) and ASR/SROM (n = 13). Blood serum metal ion levels were collected before and after revision surgery. The haematoxylin and eosin tissue sections were graded on the presence of fibrin exudates, necrosis, inflammatory cells and corrosion products. The corrosion products were identified based on visible observation and graded on abundance. Two independent observers blinded to the clinical patient findings scored all cases. Elemental analysis was performed on corrosion products within tissue sections. X-Ray diffraction was used to identify crystalline structures present in taper debris.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 7 | Pages 901 - 907
1 Jul 2012
Esposito CI Walter WL Roques A Tuke MA Zicat BA Walsh WR Walter WK

We analysed 54 alumina ceramic-on-ceramic bearings from total hip replacements retrieved at one centre after a mean duration of 3.5 years (0.2 to 10.6) in situ. These implants were obtained from 54 patients (16 men and 38 women) with a mean age of 67 years (33 to 88) who underwent revision for a variety of reasons. Posterior edge loading was found in the majority of these retrievals (32 out of 54). Anterosuperior edge loading occurred less often but produced a higher rate of wear. Stripe wear on the femoral heads had a median volumetric wear rate of 0.2 mm3/year (0 to 7.2). The wear volume on the femoral heads corresponded to the width of edge wear on the matching liner. Anteversion of the acetabular component was found to be a more important determinant than inclination for wear in ceramic bearings. Posterior edge loading may be considered to be a normal occurrence in ceramic-on-ceramic bearings, with minimal clinical consequences. Edge loading should be defined as either anterosuperior or posterior, as each edge loading mechanism may result in different clinical implications.


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 4 | Pages 430 - 435
1 Apr 2008
Biant LC Bruce WJM Assini JB Walker PM Walsh WR

This prospective study presents the ten-year (5 to 16) clinical and radiological results of 55 primary total hip replacements (THR) using a cementless modular femoral component (S-ROM). All patients had a significant anatomical abnormality which rendered the primary THR difficult.

The mean Harris hip score was 36 (12 to 72) pre-operatively, 83 (44 to 100) at five years, and 85 (45 to 99) at ten years. The Western Ontario and McMaster Universities osteoarthritis index (WOMAC) and short-form (SF)-12 scores were recorded from the year 2000. The mean SF-12 score at five years after surgery was 45.24 (22.74 to 56.58) for the physical component and 54.14 (29.20 to 66.61) for the mental component. By ten years the SF-12 scores were 42.86 (21.59 to 58.95) and 51.03 (33.78 to 61.40), respectively. The mean WOMAC score at five years post-operatively was 25 (0 to 59), and at ten years was 27 (2 to 70).

No femoral components were radiologically loose, although five had osteolysis in Gruen zone 1, three had osteolysis in zone 7, and two showed osteolysis in both zones 1 and 7. No osteolysis was observed around or distal to the prosthetic sleeve. No femoral components were revised, although three hips underwent an acetabular revision and two required a liner exchange. At a mean of ten years’ follow-up the S-ROM femoral component implanted for an anatomically difficult primary THR has excellent clinical and radiological results.


The Journal of Bone & Joint Surgery British Volume
Vol. 79-B, Issue 3 | Pages 422 - 427
1 May 1997
Wallace AL Walsh WR van Rooijen M Hughes JS Sonnabend DH

In severe forearm injuries, the diagnosis of disruption of the interosseous membrane is frequently delayed and sometimes missed, giving difficulties in the salvage of forearm stability.

We studied the structure and function of the interosseous membrane in 11 cadaver preparations, using mechanical and histological analysis. Seven of the specimens tested in uniaxial tension sustained a mid-substance tear of the central band of the membrane at a mean peak load of 1038 ± 308 N. The axial stiffness was 190 ± 44 N/mm with elongation to failure of 10.34 ± 2.46 mm. These results provide criteria for the evaluation of reconstructive methods.

A preliminary clinical investigation of the use of ultrasound suggests that this may be of value in the screening of patients with complex fractures of the forearm, and for investigating the natural history of tears of the interosseous membrane.