Education · hand

Thumb UCL injury Info

Reviewed by Dr Kieran Hirpara, Specialist Orthopaedic Surgeon Last reviewed

What you're feeling

You may notice pain on the inner side of your thumb, right at the main knuckle. This is where the ulnar collateral ligament sits. This ligament helps keep your thumb stable when you grip or pinch. When it tears, that stability is lost. You might feel a sense of looseness or weakness in your thumb. Simple tasks like holding a coffee cup or turning a key can become difficult.

The pain often flares up after you use your hand. Activities that involve pinching or gripping tend to make it worse. You might feel a sharp ache immediately after an injury, such as a fall on an outstretched hand. Over time, the pain can become a dull throb. It may hurt more at night, especially if you sleep on your side and put pressure on your hand. Waking up with a stiff or painful thumb is common.

Daily movements can feel awkward. You might struggle to reach behind your back to fasten a bra. Tucking in a shirt or buttoning a coat can be painful. Your thumb may feel like it is giving way when you try to lift something heavy. This happens because the ligament is no longer holding the joint tightly in place. Without treatment, this instability can worsen. The joint may become progressively less stable.

Sometimes, you might see a small piece of bone near the injury site on an X-ray. This is called a fleck sign. If this bone fragment is displaced, it can get caught in the joint. This specific issue often requires surgical repair to restore proper function. Your surgeon will assess your thumb through a physical exam and X-rays to check for this. They will also look for other underlying issues, such as a benign bone growth, which can sometimes mimic these symptoms.

While some injuries heal with rest and splinting, others need more intervention. The decision to operate depends on your specific injury and lifestyle. If surgery is needed, modern techniques can help restore stability. Many patients report significant improvements in pain and function within three to twelve months after repair. Whether you choose non-surgical care or surgery, the goal is to get your thumb back to normal use.

What's actually happening

Your thumb has a small ligament on the inner side called the ulnar collateral ligament. Think of this ligament as a strong rope that holds your thumb joint steady. When you injure it, this rope tears in stages. This tearing causes your thumb joint to become loose and unstable. You might feel like your thumb is giving way when you try to grip things.

The shape of your bone end does not cause this tear. However, if a small bone chip breaks off during the injury, it can get stuck in the joint. This blockage prevents the ligament from healing on its own. It often requires surgical repair to fix.

Your other finger muscles help stabilize this joint. When these muscles are weak or tired, they place more stress on the injured ligament. This extra stress can make the injury worse or slow your recovery. Rest is essential to let these muscles recover and reduce strain on the ligament.

We offer different ways to repair this tear. We can use your own tissue or a synthetic tape to reinforce the ligament. Both methods aim to restore normal movement and stability. We do not over-tighten the joint. This allows you to move your thumb naturally after healing.

Surgery is not always the first step. The need for an operation depends on your specific injury and your goals. If you are an athlete, we balance quick recovery with long-term joint health. Many patients see significant improvement in pain and function within three to twelve months after repair.

What we can do about it

How Dr Kieran Hirpara, an upper-limb surgeon at Mater Private Hospital Rockhampton, approaches this in our clinic, your treatment plan depends on whether your injury is new or long-standing. We start with self-management and physiotherapy. You can try changing your activities to avoid painful movements. Our physiotherapists focus on strengthening the muscles around your thumb joint. This helps stabilize the joint and reduce pain. We usually recommend giving this approach enough time to work before considering other options.

If pain persists, we discuss medical management. This may include pain medication or anti-inflammatory drugs to help you manage discomfort. In some cases, we consider injections. Cortisone injections can reduce inflammation and pain for a limited time. Hyaluronic acid injections aim to lubricate the joint. Platelet-rich plasma (PRP) injections use your own blood components to support healing. The effect of these treatments varies, and we discuss the likely duration of relief with you.

Surgery is considered when conservative care has not provided enough improvement, or if your injury is structural and acute. For example, if an X-ray shows a displaced bone fragment, it may indicate a Stener lesion that requires surgical repair. In these cases, surgery may be recommended straight away. Our goal is to restore stability to your thumb joint. We view this as a shared decision, based on your specific needs and the severity of your injury.

What to expect

Your thumb’s ulnar collateral ligament (UCL) is a key stabilizer on the inner side of the joint. If this ligament tears, the joint can become unstable. This instability often worsens over time if the injury is not addressed. Without proper care, the joint may remain loose and painful, affecting your grip and daily tasks.

If you choose surgery, your surgeon will repair or reconstruct the ligament. Many patients see significant improvements in pain and function within three months after the procedure. These benefits continue to grow, with many reporting better outcomes at one year. For athletes, returning to play is possible. Studies show that players who had this surgery played a similar number of games per season and had similar career lengths as those who did not.

Recovery involves protecting the joint while it heals. You may wear a thumb spica cast or brace to keep the ligament safe. This protection allows for an earlier return to activity, though it can place extra stress on nearby joints. Your team will balance early movement with long-term stability. Some techniques use non-biological materials or tendon grafts to rebuild the ligament. These methods offer comparable short-term results, potentially allowing for a faster start to rehabilitation.

If you manage the injury without surgery, outcomes vary. Some people find relief with rest and bracing, while others continue to experience weakness or pain. The decision to operate depends on your specific injury, your activity level, and your personal goals. Your surgeon will discuss which path offers the best chance for a stable, functional thumb.

It is important to have realistic expectations. No repair or reconstruction can fully restore the ligament to its pre-injury strength. However, with proper care, most people regain enough function for daily life and sports. Your commitment to rehabilitation plays a major role in your final result.

When to see someone

See your GP if you have persistent pain, weakness, or instability in your thumb after an injury. Ask for a specialist review if your thumb locks or gives way. Seek care if symptoms interfere with sleep or work. Sudden worsening of pain also warrants a check-up. Your surgeon will assess you with a history, clinical examination, and radiographs. This helps identify issues like a displaced bone fragment or underlying conditions. Early assessment ensures you get the right treatment for your thumb ulnar collateral ligament injury.