Closed Central Slip Injury: Advice and Exercises

Patient Information

Hand Therapy / Fracture Clinic

Injury to your extensor tendon

You have injured a tendon on the back of your finger known as the central slip. This tendon plays a key role in straightening the middle joint of your finger, called the proximal interphalangeal (PIP) joint.

There are two main types of central slip injuries:

• Central slip avulsion fracture — This occurs when a small fragment of bone is pulled away from the finger at the time of injury, along with the tendon
• Tendinous rupture — This refers to a direct tear of the tendon itself

Both types of injury typically cause pain, swelling and increasing difficulty straightening the middle joint of the finger. These symptoms may develop over the first few weeks after your injury.

If the injury is not treated, it can lead to a finger deformity known as a Boutonniere deformity. This means you may not be able to fully straighten the middle joint of your finger, while the fingertip joint of your finger bends backwards more than normal. See picture below.

Treatment

Your injury will be managed using a splint. This must be worn on your finger 24 hours a day. The purpose of the splint is to keep your finger in the correct position, so that the injured tendon can heal and form stable scar tissue.

The length of time you will need to wear the splint depends on the type of central slip injury you have sustained. Your therapist will advise you of the timescale of full-time splint use based on your individual injury.

As a guideline, the timescales are outlined below; however, these may alter depending on how your injury is healing. You should be guided by your therapist, with regards to timescales, at all times.

Central slip avulsion fracture - 3 to 6 weeks continuous use of the splint.

Tendinous rupture – 6 to 8 weeks continuous use of the splint.

Splintage

Your therapist will make you a custom-made splint. This splint must be worn at all times to protect the healing tendon.

Examples of the types of splints can be seen below:

If you are changing the tape on your splint, or removing the splint to check your skin, it is important that the middle joint of your finger does not bend. If the middle joint bends, the weak healing tissue may be damaged, and you will need to restart your splint treatment from day one.

Please note – Your injury will not heal if you remove the splint before you are advised to.

Important information

• You must wear your splint(s) at all times
• Keep your splint(s) clean and dry. When having a bath / shower, cover your splint to keep it dry
• Regularly elevate your hand higher than your heart to reduce swelling, if your finger is swollen
• You can do light activities in your splint(s), for example eating, dressing, using phone, typing

Contact the Hand Unit if you are having problems with your splint(s).

Exercises / advice

While you are wearing your splint, it is important to keep the top joint of your finger moving. At regular intervals throughout the day, make sure you fully bend and straighten the top joint of your finger as shown in the picture below: -

Progressing out of your full-time splint

At the end of the full-time splinting period, your therapist will assess your. If you are still unable to fully straighten your finger, you may be advised to wear your splint full-time for a few more weeks. Once your therapist is happy that you can fully straighten your middle joint, you will be given a different type of splint. This will further protect the tendon while it continues to heal and become strong.

Weaning out of your splint

When advised by your therapist, you can gradually reduce the amount of time you wear your full-time splint. You will then be given one of the splints below. You will need to wear this splint during the day and will be advised to wear your original splint at night.

Example of Capener splint

Example of Relative motion extension splint

In your daytime splint, you can bend and straighten your finger, but don’t force your finger. You can use your hand for light use but avoid heavy gripping until 10-12 weeks after your injury.

Milestones

Important information

‘Listen’ to your hand. Do not do activities that cause pain, and do not ‘over-do’ it. The tendon is not fully strong until about 12 weeks after injury.

Hand Unit contact details

Wigan Infirmary Hand Therapy Department
Hours available - 08:00- 16:00
Fracture Clinic
0300 707 2103

Wrightington Hand Therapy Department
Hours available - 08:00- 16:00
0300 707 6305
wwl-tr.therapyadmin@nhs.net

Leigh Health Centre Therapy Department
Hours available - 08:00- 16:00
0300 700 1597
wwl-tr.leighphysio@nhs.net

Boston House Therapy Department
Hours available - 08:00- 16:00
0300 707 1113
wwl-tr.mskphysio-bostonhouse@nhs.net

References

https://fifevirtualhandclinic.co.uk

Acknowledgments

Thank you to NHS Scotland for allowing free access / use of their images.