“Botox” injection: Information leaflet for patients, families and therapists - Adolescent Infraspinatus

Botulinum toxin (also known as Botox) is a purified form of a toxin that affects the nerves (a neurotoxin). It works by blocking signals from the nerve to the muscle that has been injected. The nerve is then unable to tell the muscle to move.

Muscles usually work in pairs or groups where one switches on (prime mover) and the other (antagonist) switches off to allow movement around a joint. Nerve injuries can sometimes lead to problems with muscles and their ability to switch on and off. Sometimes both groups of muscles switch on at the same time (a bit like a tug-ofwar between the muscles). We call this co-contraction. If both sets of muscles are  co-contracting it can limit the amount of movement in a joint. Botox switches off the muscle which is overworking and allows the ‘prime mover’ to do its job.

It is also suggested that Botox may have an effect on the brain’s ability to talk to the muscles. It is thought that Botox is able to help with the mixed messages being sent and received by the brain (similar to turning a computer off in order to reset it).

The aim of Botox is to improve the every day use of the affected arm and to help prevent contractures, deformities and neglected use of the arm.

The injection may take 3 weeks to take full effect. The main thing patients often notice is that the arm feels freer. For example movements such as reaching and bringing the hand to mouth may become easier.

It is best to start the exercises that are outlined in this leaflet as soon as possible following the Botox injection. It is advised that formal physiotherapy starts from 3 weeks after the injection. This may be at the RNOH or at your local Physiotherapy department.

Your Infraspinatus muscle have been injected because you have been limited in the amount you can bring your hand towards your stomach.

It may take up to three weeks for Botox to take full effect and it is important that you try to keep using the arm as you normally would during this time.

You will be given an appointment to see a physiotherapist approximately 3 weeks after the injection.

This can either be at the RNOH or at a hospital which is more local to you if preferred (appointment to be arranged prior to receiving Botox injection).

The following exercises are recommended following the injection. The exercises should be done frequently (at least 5 times a day with approximately 20 repetitions).

You should also continue with any exercises or stretches that you have previously been given by your therapist.

1. Keep your elbow bent to 90 degrees and close to your waist (a). Use your unaffected hand to rotate your arm inwards in order to bring your affected hand/wrist to your stomach (b).
   
2. Stand/sit in front of a table. Keep your elbow close to your waist and forearm out in front of you (a). Rotate your arm inwards to slide your hand along the surface and towards your body (b).
   
3. Stand/sit with your elbow close to your side.  Rotate your arm inwards
   

Everyday activities to encourage hand to midline:

• Doing buttons/zip
• Use both hands to hold cup/bottle when drinking