header advert
Results 1 - 4 of 4
Results per page:
Applied filters
Research

Include Proceedings
Dates
Year From

Year To
Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 270 - 270
1 Jul 2014
Elliott W Kaimrajh D Sawardeker P Milne E Ouellette A Latta L
Full Access

Summary

The significance of matching radius of curvature of the radial head implant and the capitellum in implant selection is evaluated. A mismatch of radius of curvature could lead to point loading, reducing contact area, creating large contact stresses, resulting in arthritis, pain, and other complications.

Introduction

Radial head (RH) implant size is chosen by reconstruction outside of the radiocapitellar joint capsule measuring the RH diameter and length, which is replicated for implant selection. RH radius of curvature (RC) is rarely part of the decision although important in determining contact area.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 232 - 232
1 Jul 2014
Ouellette E Elliott W Latta L Milne E Kaimrajh D Lowe J Makowski A Herndon E Kam C Sawardeker P
Full Access

Summary

For injuries to the lower leg or forearm, supplemental support from soft tissue compression (STC) with a splint or brace-like system and combined with external fixation could be done effectively and quickly with a minimal of facilities in the field.

Introduction

Soft tissue compression (STC) in functional braces has been shown to provide rigidity and stability for most closed fractures, selected open fractures and can supplement some other forms of fracture fixation. However, soft tissue injuries are compromised in war injuries. This study was designed to evaluate if STC can provide adequate rigidity and stability either with, or without other forms of fixation techniques of simple fractures or bone defects after standardised soft tissue defects. The load was applied either axially or in bending as the bending configuration is more like conditions when positioned on a stretcher in the field.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 272 - 272
1 Jul 2014
Elliott W Sawardeker P Kam C Ouellette A Latta L
Full Access

Summary

Increased lateral ulnotrochlear joint space due to improper sizing in radial head arthroplasty may result in medial collateral ligament laxity, leading to increased osteophytes and arthritis.

Introduction

Radial head (RH) arthroplasty is a common response to comminuted RH fractures. Typical complications include improper sizing, leading to changes in joint kinematics. Evidence of these changes should be visible through fluoroscopic images of affected joints. The two examined changes in this study are the ulnar deviation from distal radial translation (DRT), and the widening of the lateral ulnotrochlear joint space (LUT).


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 271 - 271
1 Jul 2014
Elliott W Sawardeker P Kaimrajh D Kam C Milne E Ouellette A Latta L
Full Access

Summary

Consistent load distributions with over-sizing of radial head implants show minimal variance in interosseus ligament (IOL) and triangular-fibrocartilage complex (TFCC) tension, both of which are essential in distribution of load at the elbow.

Introduction:Changes in loading distribution at the elbow have not been studied with radial head (RH) arthroplasty. Difficulty arises concerning distribution variability between loading methods and magnitudes, and with implant oversizing.

Method

RC joint capsule were exposed using the Kocher approach in seven fresh-frozen cadaver Humeri. Specimens were loaded axially in an MTS machine with humeri at 90° and wrist neutral. The arms were cycled in load control between 13N–130N until steady-state was reached for each trial. After loading in neutral, the arms were rotated to 60° supination (60S) and 60° pronation (60P), the test repeated. The radial head was excised and Co-Cr implant inserted. Sizings 0mm, +2mm, +4mm were simulated using 2mm plastic spacers on the stem. A Tekscan pressure map transducer at RC recorded loading. The recorded Tekscan loads were organised according to sizing (native, 0mm, +2mm, +4mm) for each specimen. The max/min load values were recorded and the difference, ΔL was calculated. The Max and ΔL values from each sizing were percentage paired with the respective native value. The ΔL values were used to discern load distribution. A linear regression was done using the RC loading plotted against the applied load to visualise the change of load distribution with changing applied loads. Data was analyzed using one-way analysis of variance.