The Sprained Thumb: A 6-Step Guide for Patients
Whether skiing or not, it’s quite common to seriously injure your thumb from a fall or twisting injury. If severe, a ‘skier’s thumb’ often requires surgery and is best repaired shortly after the injury.
Today’s article will bring you up to speed on understanding thumb sprains so you’re equipped to make decisions in the best interest of your health (deeper dive article available here).
1. What is a skier’s thumb?
While there are many names for the injury (skier’s thumb, gamekeeper’s thumb), this is a common injury that results from a tear of the thumb ulnar collateral ligament (UCL).
When functioning normally, the thumb UCL gives stability to your thumb when you pinch. When torn, the thumb becomes unstable with pinch. The thumb simply gives away with any force (see Figure 1).
Figure 1: Notice the torn UCL ligament compared to the intact ligament on the other side of the joint
While the name may make it sound benign, these injuries can be serious. If the tear is complete, it typically requires surgery.
Thumb UCL injuries occur with any forced ‘abduction’ injury, whether from a fall, a ski pole, or a sports contact injury. Abduction is pulling the thumb away from the index finger. Adduction is the movement of the thumb toward the index finger.
As an example, this is a common injury in football quarterbacks. If the hand is struck while throwing the ball (video linked here), the thumb can be forced into abduction, resulting in a thumb UCL tear.
2. What are the symptoms of Skier’s thumb?
The symptoms of a Skier’s thumb include pain, swelling, bruising, or a sense of instability when pinching. These symptoms are felt primarily on the inside of the thumb (near the webspace).
Because the thumb ulnar collateral ligament gives support to our thumb for pinch, a tear of this ligament will lead to painful instability with use of the thumb. It cannot be understated how critical this ligament is to the normal functioning of our hand.
3. How do I know if I have a Skier’s thumb?
The diagnosis of a Skier’s thumb can be a little tricky. It certainly is one that benefits from visiting a hand specialist who can detect subtle differences in the ‘tension’ of your thumb ligaments.
But. There are some telltale signs that make a thumb UCL injury more likely. Refer back to Figure 1 to help you locate the anatomy. If you are tender when you push directly on the inside of your thumb at the injured joint, it is likely you sprained or tore the UCL.
Beyond that, a hand specialist can gently grasp your thumb and carefully move it from side to side. I typically will compare how the tension of your injured ligament feels with your uninjured side.
In a completely torn UCL, as I move your thumb to the side, I will be unable to detect any firm endpoint to the tension of your ligament. Instead, the bones just keep sliding (yikes).
If there is any doubt, or if we are considering non-operative treatment for a partial tear, an MRI seals the diagnosis. MRI shows us the torn ligament and how much it has retracted.
In these cases where the examination is unclear, it is important to obtain an MRI quickly so the decision can be made for timely surgery if needed. The sooner the surgery is performed, the better the outcome.
4. What is the treatment for Skier’s thumb?
Skier’s thumb treatment is 100% predicated on the extent of your tear.
Partial tears of the thumb UCL that are identified and treated immediately can be immobilized in a cast (no surgery needed). Typically, you can expect about 4-6 weeks in a cast, followed by a transition period with a brace.
I restrict heavy thumb activity in such patients for 3 months after the start of casting. Even with perfect non-surgical treatment, most of these patients note a lingering soreness in the thumb for 6-9 months after the injury.
It’s a slow recovery.
If the tear is complete, the majority of hand surgeons would recommend repair of the ligament. Because this ligament is so crucial to the ability to pinch, a surgical repair is the most reliable path to healing
The success of thumb UCL repair is best when completed within about 3 weeks following the injury. Beyond that, the chances of a successful repair will decrease with time.
When too much time has passed for a successful repair (after 6-12 weeks), the surgical option is a ligament reconstruction. This is a more invasive procedure that utilizes a tendon taken from elsewhere in your body to act as a replacement thumb ulnar collateral ligament.
A reconstruction surgery is generally successful but not to the same level as an immediate repair.
The bottom line? Do not delay in seeking care following a significant thumb injury.
5. What is the surgery for Skier’s thumb?
The surgery to repair a skier’s thumb involves re-attaching the ulnar collateral ligament to the bony surface from which it tore. Conceptually, this is actually pretty simple.
This ligament can rupture in different ways, but it most commonly pulls off the bone ‘distally’ (at the end nearer to your thumbnail rather than nearer to your wrist). Figure 1 actually shows the opposite - sorry about that! In this figure, it has pulled off the bone proximally, closer to your wrist. Sometimes, it will even tear in the middle or pull off a small piece of bone that we term an ‘avulsion fracture.’ Don’t worry too much about the details.
When the ligament pulls off the bone, we fix it with a small device known as a suture anchor. This anchor is a plastic or metal screw through which sutures are threaded. This screw is placed into your bone, and the exposed suture threads are woven through your ligament. The final knot will compress the ligament down to the bone so it can heal over the ensuing 6-8 weeks.
Depending on the severity of the surrounding damage, I will often secure the repair with a second suture anchor and a suture bridge between the two to protect the ligament from external stresses while it heals.
This technique is known as the ‘Internal Brace’ (Arthrex animation - I have no affiliation). This also allows me to accelerate your rehab, rather than needing to protect a single repair point more carefully.
6. What is the recovery timeline after surgery for Skier’s thumb?
Remember that ‘recovery’ is a subjective term and for some can mean the moment of no longer needing a splint all the way to returning to high-level sports.
Below is my outline of standard healing following surgery, specifically for when I use the Internal Brace technique mentioned above:
Surgery - 2 weeks: Wear a post-operative splint full-time, with no thumb use or motion.
Begin 2 weeks: Removable splint made by hand therapy, begin to work on gentle thumb range of motion exercises. No physical use of the thumb.
Begin 6 weeks: Initiate light pinching activities with therapy, and continue to work on range of motion. Wean out of brace for light activities.
Begin 8 weeks: Progress strengthening of thumb with therapy and continue to use the brace less and less.
3-4 months: Return to heavy activities and/or impact sports. Most patients feel 90% of their former selves by this point. Occasional aches and pains, or a bad day here or there are still expected.
9 months - 1 year: “Full” recovery, where you may have to stop and think about which thumb you had injured.
Wrapping it up
While there is far more to know about the ins and outs of thumb UCL injuries and their treatment, this article should give you the essentials of understanding this condition.
If you’d like even more detailed information, you can find it here. I wish you fast healing and a speedy return to optimal hand function!
