Authors of section

Authors

Fiesky Nuñez, Renato Fricker, Matej Kastelec, Terry Axelrod

Executive Editor

Chris Colton

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Collateral ligament reattachment

1. Principles

Avulsion fractures

Avulsion fractures are the result of side-to-side (coronal) forces acting on the finger, putting the collateral ligament under sudden tension. The ligament is usually stronger than the bone, causing the ligament to avulse a fragment of bone at its insertion.
Avulsion fractures result in marked joint instability.
If the fracture is not displaced, nonoperative treatment is usually indicated (buddy taping to the adjacent finger). Displaced fractures, however, must be internally fixed.
In some circumstances, the fracture is severely comminuted with multiple tiny fragments. It may be preferable to excise the fragments and reattach the collateral ligaments directly to the bone.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Animation of the injury mechanism

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Suture anchors or tunneling

Two alternative techniques are available for collateral ligament reattachment: suture anchors, or tunneling.
The advantage of suture anchors is the relative ease of the procedure. It is also a time-saving technique.
Tunneling is the more demanding procedure, but it is significantly less expensive.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

2. Approach

For this procedure a dorsal approach to the MCP joint is normally used.

tension band wiring

3. Excision of the fragments

Excise fragments

All comminuted fragments need to be removed in order to prevent osteoarthritis.
If any fragments remain attached to the ligament, they have to be excised with a fine scalpel.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Visualize the joint

Laterally deviate the phalanx in the opposite direction to gain maximal visualization of the joint (open book). Ensure that all bony fragments have been removed.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

4. Option 1: suture anchor fixation

Drill anchor hole

Keep the phalanx laterally deviated to visualize maximally the area of the fracture at the base of the phalanx.
Make a perforation of the same diameter as the anchor to be used, as close as possible to the subchondral bone.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Insert anchor

Insert the anchor according to the manufacturer’s instructions. Ensure that the whole anchor is completely buried in the bone.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Insert the sutures

Insert the sutures into the free end of the ligament.
Reapproximate the ligament to the phalanx and make a loop in each end of the thread as an anchoring pass. Tie a knot to secure the ligament to the phalanx.
Reattaching the ligament close to the subchondral bone will ensure a smooth surface for ideal mobility.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Pitfall

If the ligament is reattached too far from the joint surface, there is a sharp edge in the joint which may cause cartilage abrasion and eventually result in degenerative joint disease.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

5. Option 2: tunneling

Drill holes

A pair of parallel perforations, using a 1.0 mm drill or a K-wire, can be made as close as possible to the subchondral bone, angled from proximal to distal, and from palmar to dorsal, penetrating the opposite cortex.
A drill sleeve for soft-tissue protection is mandatory.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Insert sutures

4.0 nonresorbable, threaded sutures, with straight needles, are used.
Insert the sutures obliquely through the end of the ligament, make a loop in each end of the thread as an anchoring pass, and thread each needle through a drill hole.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

Reapproximate the ligament

Make a small incision in the opposite side of the finger to retrieve the sutures. Cut off the needles, pull the sutures to approximate the ligament, and tie a knot over the cortical bone.

Avulsion fracture of proximal phalanx MCP joint – Collateral ligament reattachment

6. Aftertreatment

Postoperatively

Immobilize the hand in a safe position for at least 3 weeks.

Aftertreatment after collateral ligament reattachment

Follow-up

See patient 5 days after surgery to check the wound, clean and change the dressing. After 10 days, remove the sutures. Check x-rays.

Functional exercises

The healing process is slower than in bone-to-bone repair and will take 3-4 weeks.

At this stage, remove the splint, and apply buddy strapping.

70_7_Reha_2

Then begin with active motion exercises.

minicondylar plate fixation