HOW TO MANAGE PIN SITE INFECTIONS

1.Why do pin site infections occur?

Pin site infections occur in virtually all patients who have a frame on their arm or leg. We expect patients to suffer from a pin site infection at least once. Some patients, who have a frame for a prolonged period, may have several pin site infections at the same or different pin sites. It is not just common – it’s almost ubiquitous.

When there is a break in the skin, such as around a wire or pin, there is the potential for bacteria to gain a foothold. Usually, this is cellulitis, but sometimes the infection can be deeper and cause osteomyelitis.

There are some factors that may increase the risk of pin site infection. If there is more soft tissue around the wire or pin, then there may be more irritation of the skin. As soft tissues will swell at some point and then the swelling recedes, parts of the pin that were previously on the ‘outside’ may become ‘inside’ due to the swelling.

This means that in the thigh, more frequent infection is expected than in the lower leg.

Where there is more skin movement, there is more irritation of the skin by the wire or pin. This is common around joints.

We believe that pin site hygiene decreases the risk of infection, but studies have not been able to demonstrate this.

We often use dressings soaked in antiseptic to keep a pin site clean from dirt. The dressings are held down by a rubber bung, or plastic tag.

2. How do we recognise pin site infection?

Pin site infection is normally manifested as cellulitis. The skin is red, hot, painful and tender to touch.Usually, it is localised around a wire or pin.

Sometimes, it will be painful enough to stop patients from weight bearing.

There may be oozing or bleeding from around a wire or pin.

Rarely, patients will be systemically unwell.

Flicking or tapping the wire can result in pain.

Sometimes patients experience localised dermatitis around a pin site. This may be due to the antiseptic solution used. This is normally marked by satellite lesions and erythema. This will usually respond to a change in antiseptics. Rex, the Frame Specialist Nurse may be able to help – he has a work mobile available during working hours. He can be contacted on 07776660847

3. How do we manage the pin site infection?

If there is just a mild erythema, and no pain, the pin site can just be observed.

If there is pain and localised cellulitis, then a short course of antibiotics is appropriate. Rest and elevation would also be helpful. We normally use flucloxacillin 1g qds for 5 days if the patient is not penicillin allergic. For those allergic, clarithromycin 500mg bd for 5 days is appropriate if the patient does not have contraindications. Please check the BNF for interactions for individual patients.

If there are several pin sites with confluent cellulitis affecting a wide area, or the patient is systemically unwell, then hospital admission is likely required for intravenous antibiotics and possible surgical treatment. Please contact Rex Turita, the Frame Specialist Nurse during working hours, or send the patient to the emergency department out of hours. He can be contacted on 07776660847

If a patient has had a course of antibiotics, and the infection returns immediately or recurrently, or there is pus weeping from the pin site, then it is likely that the wire or pin needs to be removed. This often settles down the infection, in combination with antibiotics. A new wire may be required to maintain the mechanical stability of the frame.