Introduction: Tension band wiring is a common technique for olecranon fracture fixation. The most commonly used material for the tension band is stainless steel wire. There are however problems associated with stainless steel wire. Ethibond (Ethicon Ltd, Edinburgh) has previously been cited as a suitable alternative material but not FiberWire. The biomechanical properties of FiberWire (Arthrex Ltd, Sheffield) as a tension band material have not been evaluated. This study aimed to investigate the properties of FiberWire and compare them with stainless steel wire and Ethibond.

Methods: Saw-bone olecranons were osteotomised identically to create an olecranon fracture. Identical tension band constructs were produced using stainless steel wire, Ethibond and FiberWire. The construct was tested by cyclical loading with an ESH dynamic testing machine (Brierley Hill, West Mids). A preload of 5N was applied before cyclical loading at levels up to 200N. The fracture gap was measured with a displacement transducer (Tokyo Sokki Kenkyujo Co, Japan).

Results: At loading up to 100N, the stainless steel wire allowed an average fracture gap of 200 micrometers. 5 gauge Ethibond allowed a larger fracture gap of 350 micrometers (p< 0.05). 2 gauge Fiberwire did not allow a significantly different fracture gap to Ethibond.

Discussion: The fracture gap with suture material was greater than with stainless steel wire, but still less then 0.5mm with loading of 100N. Free body diagram calculations determine that in a 70 kg man, this would correspond to the forces expected in extending the elbow against gravity. This means that these alternative materials are mechanically suitable for use in clinical practice for tension bands. This can avoid some of the complications of stainless steel wire.

Conclusion: 5 gauge Ethibond and 2 gauge FiberWire are biomechanically suitable as alternatives to stainless steel wire in tension band wire fixation of olecranon fractures.

The purpose of this study was to determine and compare the effects of radiofrequency ablation and mechanical shaving on tendon using histological and ultrastructural techniques. A single cut using a scalpel blade was used to create a standardised reproducible lesion in 12 freshly harvested ovine infraspinatus tendons. Each lesion was then subjected to either bipolar radiofrequency ablation or mechanical shaving. Specimens were either fixed in formalin and processed for light microscopy or fixed in glutaraldehyde and processed for transmission electron microscopy. Samples of normal and untreated cut tendon were analysed as suitable controls. The radiofrequency treated samples showed an area of coagulative necrosis with an average diameter of 2mm around the lesion. Conversely, the shaved samples showed viable cells up to the edges of the lesion. These findings were supported by ultrastructural appearances, which showed preservation of tendon architecture in shaved samples and widespread denaturation of the tendon matrix with loss of fibrillar structure in the radiofrequency treated samples. Radio-frequency electrical energy and mechanical shaving are often used for resection of soft tissues during arthroscopic reconstructive procedures. The effects of these techniques on tendon are not yet clearly understood. The results of this study indicate that thermal resection of tendon causes an immediate additional 2mm area of tissue necrosis which is not present after mechanical shaving. These findings may have implications for the success of arthroscopic debridement and tendon repair procedures.

Aim Radio-frequency electrical energy and mechanical shaving are often used for resection of soft tissues during arthroscopic reconstructive procedures. The effects of these techniques on tendon are not yet clearly understood. This study compared the effects of radio-frequency ablation with mechanical shaving on ovine tendon, using histological and ultra-structural techniques.

Methods: A single cut using a scalpel blade was used to create a standardised reproducible lesion in 12 freshly harvested ovine infraspinatus tendons. Each lesion was then subjected to either bipolar radio-frequency ablation or mechanical shaving. Specimens were then processed for light and electron microscopy.

Results: The radio-frequency treated samples showed an area of coagulative necrosis with an average diameter of 2 mm around the lesion. Conversely, the shaved samples showed viable cells up to the edges of the lesion. These findings were supported by ultra-structural appearances, which showed preservation of tendon architecture in shaved samples and widespread denaturation of the tendon matrix with loss of fibrillar structure in the radio-frequency treated samples.

Conclusion: These results indicate that thermal resection of tendon causes an immediate additional 2 mm area of tissue necrosis which is not present after mechanical shaving. These findings may have implications for the success of arthroscopic debridement and tendon repair procedures.