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Guyon’s canal release
Guyon’s canal release is a surgical procedure that relieves pressure on the ulnar nerve as it passes through a narrow tunnel at the wrist, treating numbness, tingling, or weakness in the ring and little fingers. By dividing the ligament that forms the roof of the canal, the procedure decompresses the nerve and allows symptoms to improve over time.
At a glance
Anaesthetic
General anaesthetic
Where
The Avenue Hospital
Day case or overnight
Day case - home the same day
First post operative review
One week after surgery
Driving
Plan not to drive for two weeks after surgery
Post Operative Hand Therapy
Routinely recommended
Splinting
Not recommended
Pain relief
Usually paracetamol and/or ibuprofen
Return to repetitive & heavy loading
Light activities within one week; heavier wrist loading usually avoided for 2-4 weeks
Release of the ulnar nerve at the wrist (Guyon's canal)
Guyon’s canal release is surgery to relieve compression of the ulnar nerve as it passes through a narrow tunnel at the wrist called Guyon’s canal, causing numbness in the ring and little fingers and, if severe, weakness of the hand’s small muscles. Compression at this site can occur from a ganglion, thickened surrounding tissue, or repetitive pressure on the base of the palm.
Who is this procedure for?
- People with numbness or tingling in the ring and little fingers due to confirmed compression at the wrist rather than the elbow
- People with weakness of the hand's small muscles attributable to ulnar nerve compression at this level
- People whose imaging identifies a specific cause of compression, such as a ganglion, within Guyon's canal - and those where there is no clear cause
- People whose symptoms have not settled with activity modification
What does the surgery involve?
Surgery involves an incision at the base of the palm over Guyon’s canal, carefully identifying and releasing the tissue compressing the ulnar nerve and its accompanying artery as they pass through this tunnel. If a specific cause is identified, such as a ganglion, this is removed at the same time.
Alternatives to surgery
Surgical release is one option for ulnar nerve compression at the wrist. Depending on your situation, the alternatives may include:
- Non-surgical management: activity modification and avoiding pressure on the base of the palm, appropriate for mild symptoms without an identifiable structural cause
- Treatment of the underlying cause: where compression is due to a ganglion or other mass, addressing this directly is central to treatment
What happens if left untreated: untreated, ongoing nerve compression can lead to progressive numbness and weakness of the hand’s small muscles, which may not fully recover if compression is severe or prolonged.
Dr Tomlinson will discuss which options suit your specific situation at your consultation.
Frequently Asked Questions
Where will my surgery be done?
At The Avenue Hospital.
How much time will I need to have away from work?
This depends on what your job involves. Desk-based work may be possible within a few days. Manual work or activities that load the base of the palm may need to be modified for a couple of weeks. Dr Tomlinson will give you advice tailored to your job at your consultation.
When will I be able to drive again?
Multiple things affect this: which hand was treated, whether you’re wearing a bandage, whether you can grip the wheel and respond safely in an emergency, whether you are driving for personal or commercial purposes, the nature of the vehicle you are driving, and your pain levels and medications. You also need to be safely in control of the vehicle for insurance purposes – you should be able to grip the steering wheel strongly with both hands and be able to take evasive action in an emergency before you get behind the wheel. As a guide: plan not to drive for two weeks after the procedure.
When can I do a full day of administrative or desk work?
Often from 2 weeks after surgery, particularly with some temporary adjustments (see below). Keeping your hand elevated and taking regular breaks helps reduce swelling and discomfort in the early days. If you need to drive to work or carry or lift objects as part of your administrative work then alternate or half days may be a prudent measure when first returning to work.
What workplace modifications might help?
Depending on your job, helpful temporary modifications can include:
– Half days or alternate days to begin with
– No heavy lifting
– Lighter duties or being off tools
– More frequent breaks
– Using a headset instead of holding a phone
– Voice-to-text or dictation instead of typing
– Keeping the hand elevated at your workstation
– Avoiding repetitive gripping
– Help with carrying or moving items
– Moving temporarily to reception or phone duties if your role is normally manual
– Protecting the wound if your work exposes your hands to water or contamination (e.g. food handling, healthcare, wet trades)
We’re happy to provide a letter for your employer outlining recommended modifications.
I take a GLP-1 medication (such as Ozempic, Wegovy, Mounjaro or Trulicity) — how does this affect my procedure?
GLP-1 medications, used for diabetes or weight management, slow the emptying of the stomach. This can increase the risk of stomach contents being present during sedation or a general anaesthetic. In line with current ANZCA guidance you’ll be asked to follow a clear-fluid-only diet for 24 hours before your procedure, followed by the standard 6-hour fast. Please tell us and your anaesthetist that you take this medication — your anaesthetist will give you specific instructions.
How long will I need to wear a splint?
Splinting is not routinely required. A bandage dressing protects the wound while it heals over the first week or two.
Will I need to see a hand therapist afterwards? May I see one if I'd like?
Hand therapy is routinely recommended.
What pain medication will I need afterwards?
Usually simple pain relief – paracetamol and ibuprofen – is all that’s needed. Some procedures are more uncomfortable and you may need stronger pain relief. We can always prescribe stronger painkillers if you need them.
Risks & complications
General risks of hand surgery
- Bleeding and bruising; rarely, a collection of blood (haematoma) that may need draining
- Infection, which may require antibiotics or, rarely, further surgery
- Pain — usually temporary, occasionally persistent
- Swelling – common, and usually settles over weeks to months
- Scarring – scars are permanent and occasionally become thickened, raised or sensitive
- Allergic reaction to the local anaesthetic, antiseptic, dressings, tape or suture material
- Delayed or problematic wound healing
- Stiffness or reduced movement in the fingers, hand or wrist
- Injury to nerves, causing numbness, altered sensation or, rarely, a painful neuroma
- Injury to blood vessels (arteries)
- Injury to tendons
- Injury to bone (fracture)
- Failure to fully relieve your symptoms, or symptoms returning over time (recurrence)
- Complex regional pain syndrome (CRPS) – an uncommon but significant condition causing ongoing pain, stiffness and swelling
- Cold intolerance – the hand becoming more sensitive to cold, usually improving with time
- The need for further surgery
- Blood clots in the leg or lung (DVT/PE) – uncommon in hand surgery, with a slightly higher risk after a general anaesthetic or prolonged immobilisation
Specific risks of this surgery
- Injury to the deep motor branch of the ulnar nerve as it winds around the hook of the hamate bone with temporary or permanent effects on nerve and therefore muscle function
- Injury to the ulnar artery, which runs alongside the nerve in this area
- Recurrent symptoms
- Numbness or weakness in the ring and little finger if the nerve does not fully recover
Anaesthetic
If you are having sedation or a general anaesthetic for this procedure, your anaesthetist will discuss the specific risks of anaesthesia with you separately.
Recovery & rehabilitation
First 48 hours
Keep your hand elevated for 48 hours to reduce bleeding and post-operative swelling. Local anaesthetic lasts 6–24 hours (occasionally 1–3 days); your hand will have numb areas during this time.
First week
Keep the dressing dry and intact until your post-operative review. You may use your hand for light activities, but listen to your hand and avoid anything that causes pain, such as lifting or gripping. Scar sensitivity and discomfort with lifting and gripping are expected in the first few weeks. Listen to your hand and do not perform activities that cause discomfort. You should find that your hand function is better each day.
Second week
The wound is settling. Numbness and tingling may take some time to improve as the nerve recovers, and this is discussed with you before surgery.
6 weeks
Full grip strength may take several months to return, and deep-pressure tenderness over the wound can persist for some months.. The scar will feel tight and firm. Massage assists with improving scar mobility and minimising scar firmness.
3 months
The scar firmness will start to resolve after 3 months, and will take up to 12 months to settle.
Long term
Nerve recovery after decompression can be gradual and, for longstanding or severe compression, may be incomplete.
Want to know more about Guyon’s Canal Release?
Contact us to schedule an appointment with Dr Tomlinson.
Fees and costs
You will receive a written financial quotation after your consultation, once your operation and any third-party requirements are confirmed. See our Fees and informed financial consent page for how our fees work, what your quotation includes, and the resources available to you.