Orthopedic Surgery for Gamekeeper's Thumb Treatment & Management

Nonsurgical treatment can be considered in partial tears of the ulnar collateral ligament, which usually involve an isolated rupture of the proper collateral portion of the ligament. This injury may be treated by immobilizing the thumb in a spica-type cast for 4 weeks, as seen in the images below. The cast should be well molded around the MCP joint, and the interphalangeal (IP) joint can be left free. With appropriate closed treatment, good to excellent results can be expected in 90% of such injuries.^[14]

Nonsurgical treatment can also be considered in patients who either refuse surgery or are too infirm to tolerate a surgical procedure. In these patients, a functional brace or well-molded spica splint can be applied, but full recovery and complete healing of the UCL cannot be expected if the tear is complete. Some reports in the literature support the use of functional bracing and early range-of-motion exercises in these patients, as well as in those with Stener lesions or complete tears.^{[15, 14]} Such reports suggest that patients recover equally well with a functional brace and daily ROM therapy regardless of the completeness of the UCL tears. However, poor UCL healing in the presence of a Stener lesion is also repeatedly confirmed in the literature.^{[13, 14]}

Medications that decrease acute swelling and allow better follow-up examination should be administered in the acute phase. Nonsteroidal anti-inflammatory drugs (NSAIDs), which decrease pain and swelling, are the drugs of choice.

Complete ulnar collateral ligament tears require surgical intervention. Some reports in the literature suggest that immobilization with a special brace designed to resist the ulnar and radial deviation of the thumb may be as beneficial as surgery in patients with these injuries.^[14] However, confirmations of these suggestions are limited.

Determine whether the ulnar collateral ligament tear is partial or complete before surgical repair. Also, determine whether the UCL tear is chronic or acute, because the procedure may be different if the UCL tear is chronic.

Radiographs should be available for assessing the presence of a fracture or subluxation of the MCP joint. If the fracture fragment is large and/or displaced or if it represents more than 10% of the articular surface, fixation is required. Small displaced avulsion fractures may be excised.

Make an incision over the ulnar border of the metacarpophalangeal joint of the thumb. Incise the adductor aponeurosis longitudinally, and retract it distally. Then expose the dorsal capsule, and assess the proper and accessory collateral ligaments. During the surgical dissection, take care to identify and protect the sensory branch of the radial nerve; it is commonly seen within the surgical field. Even with careful dissection and retraction, postoperative radial nerve neurapraxia can still occur.

If the joint is subluxed and if the soft-tissue repair seems insufficient to hold the reduced joint, a small-gauge Kirschner wire (ie, K-wire) can be inserted to maintain the MCP joint in position. The UCL can then be repaired. In a fresh injury, the torn ends of the UCL can be directly repaired. If this approach is not possible, other techniques include attachment of the ligament to the periosteum, its reattachment to the bone by using a pull-out wire, or its fixation via the periosteum and bone flap. After the UCL is repaired, reattach the adductor aponeurosis. If a small piece of avulsed bone is present, remove it; a large bone fragment should be reduced and preserved.

For chronic UCL tears older than 6 weeks, consider repairs using the capsuloligamentous structures on the ulnar border of the MCP joint. If no degenerative changes are present at the MCP joint, consider ligament reconstruction. A free tendon, usually the palmaris longus, can be woven through the metacarpal neck and the base of the proximal phalanx. If arthritis is present or if the patient is a manual laborer, consider an arthrodesis of the MCP joint. Arthrodesis does not lead to significant impairment if the motion of the IP and carpometacarpal (CMC) joints is maintained.

Postoperatively, place the patient's thumb in a spica splint, and begin carefully monitored ROM exercises of the IP and MCP joints. Alternatively, total cast immobilization for 4 weeks can be used; at 4 weeks after surgery, a removable thumb spica cast can be fabricated, and light activities of daily living (ADLs) can be initiated. The brace should be removed only for performing exercises and for hygiene. At 3 months after surgery, the patient's full activities can be resumed.

After 4 weeks, the thumb spica splint and any pins that were placed may be removed. A hand-based splint that immobilizes the MCP joint is then applied for 2 weeks. The splint is removed for therapy during this 2-week period, and active motion of the MCP joint is begun. Unrestricted usage is begun at 3 months.

Chronic instability is a complication of UCL rupture. The common cause is the patient's failure to seek medical attention for diagnosis and treatment in a timely fashion. The longer a complete UCL rupture exists, the more likely it is to progress to chronic instability, even after its repair. Success in repairing the tissues after 6 weeks has been limited. The dorsal capsule, as well as the extensor pollicis brevis and extensor pollicis longus muscles, becomes attenuated, adding to the dorsal instability of the MCP joint. The thumb then tends to become displaced volarly and to rotate into a supinated position.

Chronic instability of the MCP joint can occur despite a good repair, especially if motion and return to play are resumed prematurely. This instability is difficult to treat and can lead to arthritic changes in the MCP joint, as well as a weak pinch grasp in the long term.

Stiffness of the MCP and IP joints is a common complication. This stiffness is usually not a functional problem, and it tends to improve with time.

Neuropraxia of the radial sensory nerve may occur, even if care is taken to isolate and protect the nerve during surgical repair. The neuropraxia usually resolves spontaneously.

Early diagnosis is the most important factor that determines the functional outcome in cases of gamekeeper's thumb. In thumbs with partial ligament injuries, nonsurgical treatment by means of immobilization yields a stable, painless thumb with nearly normal motion in most cases. In more than 90% of complete ruptures that are surgically treated within 3 weeks of the injury, a good to excellent result can be expected. Repair within 1 week of the injury is optimal.

Pain and stiffness can be expected to be mild or absent, and pinch and grip strength will be nearly normal. The rate of return to former activities, including recreational sports, is reported to be as high as 96%.

The failure to diagnose this injury and the patient's failure to seek medical treatment are the most common reasons for a poor outcome.

In complete tears, the failure rate of treatment with bracing and early motion is 50%. If a patient is unable to tolerate or refuses surgery, the use of a brace or thumb spica splint is the treatment of choice. However, full stability of the thumb is unlikely.

The prognosis for all repairs and reconstructions that are undertaken longer than 6 weeks after a complete UCL rupture is poor.

The future management of gamekeeper's thumb injuries is targeted at preventing the injury and improving the outcome of reconstruction in chronic complete UCL ruptures.

Ski gloves are being designed to help prevent UCL tears that are caused by a fall onto a hand holding a ski pole. As yet, these gloves are not commercially available, and they have not been proven to be beneficial.

Multiple procedures have been attempted in efforts to improve the outcome for chronic UCL ruptures. As yet, no procedure has been as effective as direct repair of the acutely ruptured UCL. Arthrodesis of the MCP joint is still the standard salvage procedure in chronic gamekeeper's thumb injuries.