Advice

The technology

The technology

The Sternal Talon (KLS Martin Group) is a rigid fixation device for closing the sternum, or breastbone. It is made of biocompatible titanium alloy and is available in 2 variations: a single talon, which has a single foot plate to sit on each side of the sternum, and a double talon, which has 2 foot plates on each side. The single and double talons come in a range of widths and depths. Each talon is supplied in 2 parts which are inserted separately and a screw and ratchet mechanism is used to connect them.

After choosing the appropriately sized Sternal Talon devices, the surgeon exposes the rib‑sternum connection and makes cuts in the intercostal spaces. The feet of the talons do not penetrate the bone, but are hooked over each side of the open sternum into the cuts between paired intercostal spaces. Once in place, the screw is loosened to release the ratchet mechanism and the 2 halves of the talon are then pushed together to the desired width for closing the sternum using a reduction clamp. The screw is then tightened to lock the ratchet mechanism and hold the talon rigid. It can be loosened to unlock the 2 parts if removal or realignment is necessary. Care should be taken to ensure there is proper bone alignment.

Between 1 and 5 Sternal Talons are needed to close a sternum, depending on the patient. Any combination of single or double devices may be used, as deemed appropriate by the clinician. The Sternal Talon devices can be left in place indefinitely, barring any complications or reoperations. Sternal plates or wires can be used to further stabilise the sternum if needed.

Sternal Talons are marked with a 'safe zone' to indicate proper positioning; if the arrow on one foot does not fall in the safe zone of its paired foot, a more appropriately sized device should be used. Surgeons using the device should be careful not to injure the intercostal vessels; if this happens, the Sternal Talons should be removed and the vessel repaired.

Sternal Talon's instructions for use describe the procedure for emergency removal. Sternal Talons can be removed for emergency re‑entry in several ways:

  • Turning the screw anticlockwise to the 7 o'clock, open position.

  • Cutting the device at the cut points.

  • Inserting a flat screwdriver (or similar instrument) into the lock mechanism and manually disengaging the ratchet teeth.

The innovation

Unlike standard care, Sternal Talons do not need to be drilled into the bone. This means that insertion has the potential to be faster than standard practice, because the device hooks over the sternum and has a simple locking mechanism. The Sternal Talon may be more stable than standard wire closure, because it spreads the pressure load across the sternum. This may allow patients to return to normal activities sooner without disrupting sternal healing.

Current NHS pathway

Median sternotomy is a surgical procedure which involves cutting vertically along the length of the sternum, and then opening the sternum by sawing vertically using a reciprocating or oscillating saw. NHS HES data 2014–15 shows that there were 76,307 cardiothoracic procedures, many of which needed median sternotomy and subsequent closure post‑procedure. Median sternotomy provides access to the heart, lungs and surrounding structures for other procedures including coronary artery bypass surgery, heart valve replacement and lung volume reduction. After a sternotomy the sternum must be realigned and closed. Sternal closure may also be needed following sternal fractures and sternal reconstruction procedures.

Sternal closure is typically achieved using steel wires to hold the bones in place. The wires are passed through or around each sternal half and then twisted together in front of the sternum, pulling and securing them into position. Different thicknesses of wires and different techniques may be used.

Alternatives to wire closure include metal clips stapled in between each rib, bioabsorbable cords to tie the sternum together (typically used in children) and metal cables or plates that must be screwed directly into the bone.

A repeat sternotomy may be needed in patients who need further cardiothoracic surgery, or in patients who have complications after their original procedure.

Complications of median sternotomy include sternal nonunion (when the sternum fails to fuse back together), malunion (when the sternum fuses in a misaligned state), and sternal dehiscence (when the sternum becomes fully separated). The latter of these is often accompanied by mediastinitis, a serious infection of the deep soft tissues. Wound infection is also possible.

Population, setting and intended user

The Sternal Talon is designed to be used in the tertiary‑care inpatient setting. It is intended to be used only by suitably qualified surgeons who are experienced in carrying out sternal closure procedures.

The device is indicated for use in most patients having cardiothoracic procedures, although some patients' anatomies may preclude its use. It may be most suitable for people at higher risk of complications such as those with chronic obstructive pulmonary disease, obesity, diabetes and failed primary sternal wire closure.

The manufacturer states that the final decision on patient suitability remains with the surgeon. It is the clinician's responsibility to determine and choose the most appropriate size and configuration of devices.

The device is contraindicated in the following circumstances:

  • active or latent infection

  • insufficient quantity or quality of bone

  • sternal anomalies preventing correct fitting

  • severe osteoporosis

  • foreign body sensitivity

  • allergy or suspected sensitivity to the implant materials

  • inflammation in the implant region

  • bone tumours in the implant region

  • patients who are still growing.

Additional relative contraindications are:

  • osteoporosis, osteomalacia or other severe structural bone damage

  • parasternal sternotomy with very low sternal width on 1 side

  • patients with mental or neurological conditions who are unwilling or unable to follow appropriate postoperative care instructions

  • reduced compliance because of drug or alcohol misuse.

Sternal Talon devices should not be bent or modified in any way.

Costs

Device costs

Sternal Talon costs between £479.28 and £586.79 for the single‑talon version and between £636.07 and £689.84 for the double‑talon version, depending on size (excluding VAT).

It should be noted that although Sternal Talon can be used in place of wires, sometimes these wires are used in addition to Sternal Talon for extra stability. Table 1 contains prices based upon the most common configurations of the Sternal Talon device, as used in the studies reported in this briefing. One study (Levin 2010) specified a configuration using 1 single‑talon device and 2 double‑talon devices. This cost is presented with and without additional wires, because both are mentioned in the study. Typically, 3 Sternal Talons are used per sternal closure.

Costs are presented as a range, from using all of the smallest to all of the largest devices respectively. Prices in the table were provided by specialist commentators, and this was the lowest cost to add support wires.

Table 1: Cost of sternal closure using various Sternal Talon configurations

Description

Cost (min/max)

Additional information

3 single Sternal Talons

£1,437.84 to £1,760.37

Included studies present 3 Sternal Talons as the most common configuration (60% to 80% of procedures).

3 double Sternal Talons

£1,908.21 to £2,069.52

2 double Sternal Talons, 1 single Sternal Talon (no wires)

£1,751.42 to £1966.47

Configuration used in Levin (2010) study, without support wires.

2 double Sternal Talons, 1 single Sternal Talon (with 3 wires)

£1,764.08 to £1,979.13 

Configuration used in Levin (2010) study, with 3 wires; the maximum stated in their methodology.

Costs of standard care

Costs for standard wire closure were calculated based on information provided by specialist commentators, who specified which and how many wires were used. Prices were taken from the NHS Supply Chain.

  • Patients weighing less than 80 kg: 1 pack of Ethicon #5 wires W902 (2 wires, £8.48) and 1 pack of Ethicon #5 wires W905 (1 wire, £4.22). Total cost: £13.06.

  • Patients weighing more than 80 kg: 1 pack of Covidien Tyco #7 wires (4 wires, £10.20) and 1 pack of Ethicon #5 W905 (1 wire, £4.22). Total cost: £14.42.

Note that all wires in the above cost example can only be purchased in packs of 12; for example, 12 packs of Ethicon #5 wires cost £101.70 (£8.48 each).

Resource consequences

The device is currently used in 2 NHS centres.

Any sternal closure device which reduces the need for repeat procedures because of complications may reduce long‑term treatment costs.

There are no practical or infrastructure changes associated with implementing Sternal Talon in the current care pathway.