header advert
Results 1 - 7 of 7
Results per page:
Applied filters
General Orthopaedics

Include Proceedings
Dates
Year From

Year To
Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_2 | Pages 97 - 97
1 Feb 2020
Conteduca F Ferretti A Iannotti F
Full Access

Alpha Lipoic Acid (L.A.) is an effective natural antioxidant discovered in the human body in 1951 from L.J. Reed and I.C. Gunslaus from liver.

It is inside broccoli, spinach and red meats, especially liver and spleen.

Actually it is largely used as antioxidant in antiaging products according to the low toxicity level of the product.

The present study take into consideration the possibility to reduce oxidation of medical irradiated UHMWPE GUR 1050, mixing together polyethylene powder and Alpha Lipoic Acid powder.

The study is composed of two parts.

Part 1 Thermostability of alpha lipoic acid during polyethylene fusion Part 2 detection of oxygen level in artificially aged irradiated polyethylene

Solid pieces were made with Gur 1050 powder (Ticona Inc., Bayport, Tex, USA) and mixed with Alpha Lipoic Acid (Talamonti, Italy, Stock 1050919074) 0,1%-­‐0,3%-­‐0,5%-­‐1%-­‐2% and gamma ray irradiated with 30 kGy (Isomedix, Northborough, MA).

An owen (80° Celsius) was used to produce an aging effect for 35 days in the doped and control samples (Conventional not doped polyethylene). This process simulate an aging effect of 10 years into the human body.

Part 1 : THERMAL STABILITY : a Fourier Transfer Infra Red (FTIR) test was made in pieces molded in a cell at 150° and 200°Celsius and pressure of 200 MPa comparing to the UHMWPE powder mixed with alpha lipoic acid. The presence of Alpha Lipoic Acid in the polyethylene was found at any depth in the manufacts.

Part 2 : OXIDATION OF THE SURFACE : After 5 weeks at 80° Celsius in a owen (ASTM standard F-­‐2003-­‐02)A FOURIER TRANSFER INFRA RED TEST (FTIR) was made in the superficial layer and deeper on the undersurface of doped 0,1% and conventional UHMWPE.

The antioxidation limit is defined as the ratio of the area under 1740cm/−­‐1 carbonyl and 1370 cm/−­‐1 Methylene absorbance peaks.

In conventional UHMWPE oxidation is detected on the surface and decreases in the deeper layers down to zero under 1500 Micron.

In the doped UHMWPE, FTIR demonstrate a very low oxidation limit on the surface and at any depth, comparing to conventional UHMWPE.

The examples show that Lipoic Acid is effective as antioxidant in irradiated UHMWPE and it is stable with respect to thermal treatment.

For any figures or tables, please contact authors directly.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_6 | Pages 14 - 14
1 Mar 2017
Speranza A Alonzo R De Santis S Frontini S D'arrigo C Ferretti A
Full Access

Femoral neck fractures are the second cause of hospitalization in elderly patients. Nowadays it is still not clear whether surgical treatment may provide better clinical outcome than conservative treatment in patients affected by mental disorders, such as senile dementia.

The aim of this study was to retrospectively assess mortality and clinical and functional outcome after hemi arthroplasty operation following intracapsular neck fractures in patients with senile dementia.

Between 2008 and 2014, 819 patients were treated at our Orthopaedic Institute for neck fracture of the femur (mean age: 83.8 years old). Eighty-four of these showed clear signs of cognitive impairment at time of admission in the Emergency Department. Mental state of patients was assessed in all cases, as routine, at the Emergency Room with the Short Portable Mental Status Questionnaire (Sh-MMT) and the Mini Mental State Examination (MMSE).

Patients were divided in two groups depending whether they were surgically treated with hemiarthroplasty (Group B, 46 patients; 35 females, 11 males; mean age: 88.5 y.o.) or conservatively treated (Group C, 38 patients; 28 females, 10 males; mean age: 79.5 y.o.).

These two groups were compared with a matched case-control group of patients surgically treated with no mental disorders (Group A, 40 patients; 34 females, 6 males; mean age: 81.5 y.o.)

Incidence of mortality, systemic or local complications and functional clinical outcomes were evaluated with the ADL score and the Barthel index.

Mortality rate was 35% (14 patients) for Group A, 50% (21 patients) for Group B and 95% (22 patients) for Group C. Paired t-test, with significance rate set at 0.05, showed significant higher mortality rate in Group A compared to both Group B (p:0.02) and Group C (p:0.001), and also between Group B and Group C (p:0.01). Three orthopaedic complications were found in Group B (two cases of infection and one dislocation of the prosthesis) while none in Group A (p<0.001). There have been 14 overall general complication in Group A (33%), 16 in group B (38%) and 15 in Group C (65%), with significant higher rate in Group B vs. Group A (p:0.02) and in group C vs. Group B (p: 0.001)

Activity daily living scale and Barthel Index results showed higher results in Group B than Group C both in terms of recovery of walking ability and daily living (hairdressing, wearing clothes, eating).

For any figures or tables, please contact authors directly (see Info & Metrics tab above).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_1 | Pages 15 - 15
1 Jan 2016
Carcangiu A D'arrigo C Bonifazi AM De Sanctis S Alonzo R Setini A Ferretti A
Full Access

Background

Limb length discrepancy after total hip replacement is one of the possible complications of suboptimal positioning of the implant and cause of patients dissatisfaction.

Computer assisted navigation become affirmed in last years for total hip replacement surgery and it is also used for the evaluation of the intra-operative limb length discrepancy.

The purpose of this study is to verify the reliability of a navigation system with a dedicated software in intraoperative evaluation of limb lengthening and offset as compared with manual technique.

Methods

Forty patients who underwent a Total Hip Arthroplasty in our institution were entrolled in this study. Twenty patients were evaluated with pre operative manual planning (group A) and treated with hand positioning of femoral stem. Twenty Patient were evaluated with preoperative manual planning and treated with Computer assisted navigation of Stem (group B).

Mean operating time and blood loss were analyzed. Radiological and clinical follow up was made at 1, 3, 6 and 12 months postoperative to assess any mismatch of implant, complications and clinical results that was measured with Harris Hip Score.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_28 | Pages 17 - 17
1 Aug 2013
Ferretti A Iorio R Mazza D Caperna L Bolle G Argento G Conteduca F
Full Access

Introduction

The aim of this study is to investigate the accuracy and reliability of a Magnetic Resonance Imaging (MRI) based Patient Match Technology (PMT) system (VISIONAIRE, Smith & Nephew, Inc, Memphis, Tenn) by intraoperative use of VectorVision knee navigation software from BrainLAB (Redwood City, California, USA).

Methods

Between February 2011 and May 2011, 15 patients with primary gonarthrosis were selected for unilateral Total Knee Arthroplasty (TKA). The first three patients were excluded from this study, as they were considered as a warm up to set up the procedure. Therefore 12 patients entered the study. Preoperatively all patient underwent a full-length weight-bearing radiograph in antero-posterior (AP) and a MRI according to the protocol suggested and approved by the manufacturer. All patients were operated with cemented posterior stabilised prosthesis cruciate ligament sacrificing (Journey BCS, Smith & Nephew, Inc, Memphis, Tennessee, USA) by the same surgeon using the VISIONAIRE patient matched cutting jigs. During surgery, once the guides were placed and fixed, the orientation was checked by the navigator. The following parameters were evaluated: size of the implant, alignment in coronal and sagittal plane. An unsatisfactory result was considered an error ≥ 2° in both plane for each component as a possible error of 4° could result in aggregate.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_28 | Pages 15 - 15
1 Aug 2013
Ferretti A Conteduca F Mazza D Maestri B Bolle G Argento G Redler A Iorio R
Full Access

Introduction

In total knee arthroplasty extramedullary tibial guides could not to be as accurate as requested in obtaining proper alignment perpendicular to the mechanical axis. The aim of this study was to determine the accuracy of an accelerometer-based system (KneeAlign 2; OrthAlign Inc, Aliso Viejo, California) as evaluated by post-op X-rays analysis.

Methods

Between March 2012 and May 2012 thirty consecutive patients with primary gonarthrosis were selected for unilateral total knee arthroplasty (TKA) using a handheld surgical navigation system to perform the tibial resection.

Navigation procedure: The entire system is provisionally secured to the tibia using a spring placed around the leg and is fixed to the proximal aspect of the tibia using 2-headed pins. Before fixing the system proximally, an aiming arm is used to align the top of the device with the anterior cruciate ligament footprint and the medial one third of the tibial tubercle. Distally, a footplate connected to the tibial jig is used to keep the EM jig a set distance off of the tibial surface. A gyrometer within the navigation unit is then able to calculate the posterior slope of the tibial jig. Subsequent anatomical landmarkings of both the lateral and medial malleoli are identified using the distal aspect of the EM jig to establish the tibia's mechanical axis. Similarly, the gyrometer within the navigation unit is able to calculate the varus or valgus alignment of the tibial jig relative to the tibia's established mechanical axis. Once anatomical registration has been performed, the tibial cutting block is placed at the proximal aspect of the device, and real-time feedback is provided by the navigation unit to the surgeon, who is then able to set the cutting block's varus/valgus and posterior slope alignment before performing the tibial resection.

Postoperatively, standing anteroposterior hip-to-ankle radiographs and lateral knee-to-ankle radiographs were performed to determine the varus/valgus alignment and the posterior slope of the tibial components relative to the mechanical axis in both the coronal and sagittal planes. The difference between the intraoperative reading of the tibial varus/valgus alignment and posterior slope provided by the system was compared to the radiographic measurements obtained postoperatively for each respective case. Differences were analysed via standard t test. The critical level of significance was set at P <0.05.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 151 - 151
1 Mar 2013
Conteduca F D'Angelo F Conteduca J Iorio R Ferretti A
Full Access

Alpha Lipoic Acid (L.A.) is an effective natural antioxidant discovered in the human body in 1951 from L.J. Reed and I.C. Gunslaus from liver. It is inside broccoli, spinach and red meats, especially liver and spleen. Actually it is largely used as antioxidant in antiaging products according to the low toxicity level of the product.

The present study take into consideration the possibility to reduce oxidation of medical irradiated UHMWPE GUR 1050, mixing together polyethylene powder and Alpha Lipoic Acid powder.

The study is composed of two parts.

Part 1 Thermostability of alpha lipoic acid during polyethylene fusion

Part 2 detection of oxygen level in artificially aged irradiated polyethylene

Solid pieces were made with Gur 1050 powder (Ticona Inc., Bayport, Tex, USA) and mixed with Alpha Lipoic Acid (Talamonti, Italy, Stock 1050919074) 0, 1% and gamma ray irradiated with 30 kGy (Isomedix, Northborough, MA).

An oven (80° Celsius) was used to produce an aging effect for 35 days in the doped and control samples (Conventional not doped polyethylene). This process simulate an aging effect of 10 years into the human body.

THERMAL STABILITY: a Fourier Transfer Infra Red (FTIR) test was made in pieces molded in a cell at 150° and 200°Celsius and pressure of 200 MPa comparing to the UHMWPE powder mixed with alpha lipoic acid. The presence of Alpha Lipoic Acid in the polyethylene was found at any depth in the manufacts.

figure 1: A Pure Lipoic Acid. B Lipoic Acid + UHMWPE melted 150° C. Lipoic Acid + UHMWPE melted 200° C° (A And B spectra subtracted UHMWPE)

OXIDATION: After 5 weeks at 80° Celsius in a oven (ASTM standard F-2003-02)A FOURIER TRANSFER INFRA RED TEST (FTIR) was made in the superficial layer and deeper on the undersurface of doped 0.1% and conventional UHMWPE.

The antioxidation limit is defined as the ratio of the area under 1740 cm/−1 carbonyl and 1370 cm/−1 Methylene absorbance peaks.

In conventional UHMWPE oxidation is detected on the surface and decreases in the deeper layers down to zero under 1500 Micron Fig 2.

figure 2 Pure polyethylene: A Surface, B 1500 Micron, C 3000 Micron

In the doped UHMWPE, FTIR demonstrate a very low oxidation limit on the surface and at any depth, comparing to conventional UHMWPE Fig 3.

figure 3 Doped UHMWPE A surface, B 700 micron deept, C 1700 micron deept

The examples show that Lipoic Acid is effective as antioxidant in irradiated UHMWPE and it is stable with respect to thermal treatment.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXV | Pages 222 - 222
1 Jun 2012
Speranza A Maestri B Monaco E D'arrigo C Ferretti A
Full Access

Manual postoperative CT calculation of anteversion and inclination of the acetabular cup can be inaccurate and depends on the observer's experience. The aim of this study is to describe and present a validation of a new CT-image-based dedicate software (EGIT) for calculation of the acetabular component placement.

The software principle is based on a three-dimensional reconstruction of a patient's bones from anatomical data collected postoperatively on the patient's CT scan.

15 Patient to be operated for THR were enrolled in this study. All patients were evaluated with post operative CT-scan. Measurement of Cup positioning were performed with two different methods: a manual method, performed by an expert radiologist, and a software CT image based method. Statistical analysis was performed with Intraclass Correlation Coefficent to asses interobserver and intraobserver reliability. A paired T-test was used to detect differences between manual and software methods.

The Intraclass Correlation Coefficient was excellent for both the intraobserver and interobserver reliability. As expected the ICC is higher in the interobserver case.

A mean cup anteversion of 14.2 (S.D. ±6.9), mean inclination of 44.2 (S.D.± 5.8) are detected with EGIT by the expert surgeon; Mean Cup anteversion of 13.6 (S.D. ± 5.11), mean inclination of 43.3 (S.D.± 5.1) are detected with manual method by expert radiologist. No statistical difference have been found (P> 0.05).

The EGIT software seems to be an easy, accurate and reproducible method to calculate acetabular cup positioning using standard post-operative CT scan in THA.