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Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_8 | Pages 17 - 17
10 May 2024
Morris H Shah S Murray R
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Introduction

The health sector contributes the equivalent of 4.4% of global net emissions to the climate carbon footprint. It has been suggested that between 20% and 70% of health care waste originates from a hospital's operating room, the second greatest component of this are the textiles used, and up to 90% of waste is sent for costly and unneeded hazardous waste processing.

Waste from common orthopaedic operations was quantified, the carbon footprint calculated, and cost of disposal assessed. A discussion of the circular economy of textiles, from the author of the textile guidance to the Green Surgery Report follows.

Methods

The amount of waste generated from a variety of trauma and elective orthopaedic operations was calculated across a range of hospital sites. The waste was separated primarily into clean and contaminated, paper or plastic. The carbon footprint and the cost of disposal across the hospital sites was subsequently calculated.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_9 | Pages 9 - 9
1 Oct 2022
Rahman T Baxan N Murray R Tavana S Schaer T Smith N Bull J Newell N
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Introduction

Nucleus replacement surgery has the potential to be an early treatment option for chronic lower back pain. The surgery involves removal (nuclectomy) and replacement of the native degenerated nucleus with a material designed to restore the disc's physiological properties. Multiple techniques have been considered to perform a nuclectomy, however the advantages and disadvantages of each are not well understood. The aim of this study was to quantitatively compare three nuclectomy techniques: automated-shaver, rongeurs, and laser.

Methods and results

Fifteen human vertebra-disc-vertebra lumbar specimens were split into three groups. Before and after nuclectomy axial mechanical tests were performed and T2-weighted 9.4T MRIs were acquired for each specimen. Using the automated-shaver and rongeur similar volumes of disc material were removed (2.51±1.10% and 2.76±1.39% of the total disc volume, respectively), whilst considerably less material was removed when using the laser (0.12±0.07%). Using the automated-shaver and rongeur significantly reduced the toe-region stiffness, while the linear region stiffness was significantly reduced only in the rongeur group. From the MRIs, more homogeneous cavities were seen in the center of the disc when using the automated shaver compared to rongeur, whilst laser ablation resulted in small, localized cavities.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_7 | Pages 1 - 1
1 May 2016
Murray R Juszczyk M Frankle M Uhlenbrock A Kelnberger A Heinrich W
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A secure taper connection in shoulder arthroplasty is mandatory to avoid loosening and fretting. This study's objective was to determine the amount of in situ force used by surgeons to seat a humeral head and to determine the disengagement force of the taper connection. The influence of 1) material type, 2) head size, and 3) surgeon on the impaction force and the fixation (pulloff force) of the sample was examined.

Methods

Impaction data was collected from experienced shoulder surgeons (n=5) during a cadaver lab. Testing groups (n=5 each) were: 1) small ceramic, 2) big ceramic, 3)small metal and 4) large metal. Twenty centric, anatomic humeral heads (DJO surgical, Vista, CA, TURONTM, material: CoCrMo or BIOLOX®delta, size: 38×14mm or 54×22mm) were paired with a corresponding humeral neck (TURON™, DJO surgical, type: neutral modular, material: CoCrMo). Each taper was always used with the same humeral head throughout testing.

The impaction force sequence was recorded using an instrumented impactor (Piezo sensor, model 208 C05, PCB PIEZOTRONICSINC, Depew, NY, ±1%). The surgeons impacted all samples into the cadaver using their typical pattern of hammer strikes (Figure 1). The engaged humeral head and taper were removed by hand and then disengaged using an instrumented (U93, HBM, Darmstadt, Germany, load limit: 5kN) hand-held pulloff-device.

Statistics and data analysis were performed in MATLAB (2014b, Mathworks, Natick, MA, α=0.05). Two-tailed, pearson's linear correlation coefficients are reported. Group differences were determined using Kruskal Wallis test. Pair-wise comparisons were performed using a Tukey correction.

Results

Extremely high and variable impaction forces were measured (Table 1, Figure 2). The maximum force was nearly 27 kN; however, that value reduced to ∼18kN when the data from an outlier surgeon was removed. Maximum impaction forces were 12.45±4.36 kN, and the average was 10.47±3.63 kN. The pulloff force ranged from 0.94 kN to 5.54 kN with an average of 2.76±1.19 kN. Higher impaction forces required higher pulloff forces to disengage the taper connection (p<0.001, R>−0.608).

Ceramic humeral heads showed a 24% higher fixation strength (p=0.004) under similar engagement conditions (p=0.18) in comparison to metal components.

Head size does not appear to influence either the magnitude of the impaction force surgeons use (p>0.20) nor the force needed to disengage the taper (p=0.25).

The surgeon performing the insertion had a significant influence on the impaction strike timing (p<0.001), number of strikes (p<0.001), and the impaction forces (p<0.03) and the pulloff force (p<0.001).


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLI | Pages 129 - 129
1 Sep 2012
Horne G Murray R
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Revision total hip replacement may be technically challenging, with component selection being one of the challenges. Modular titanium femoral components have some advantages, and our aim was to assess the medium term outcome of the use of such a component [Revitan or PFM]

We reviewed 323 patients undergoing revision with one of these femoral stems. We applied the Oxford Hip Score, the Charnley Class, and the Devane Patient Activity Level to each patient.

The average follow up time was 6.58 years. The mean Oxford score was 35.74.39.8% of the patients were Charnley Class B. 52.4% of patients had an activity score indicating a moderate level of activity ie they could participate in gardening, swimming and other leisure pursuits.

The overall outcome was good with this prosthesis. The Oxford scores were comparable with the national mean for revision THR on the NZ National Joint Register.