Giancarlo Stanton injury: Explaining the hamate bone fracture

The Miami Marlins suffered a rough blow when Giancarlo Stanton suffered a hamate bone fracture in his left hand. The expectation is that he will be out four to six weeks undergoing surgical repair of the injury and subsequent rehab and recovery. Marlins backup infielder Jeff Baker knows a little about the injury, as he has suffered it in the past as well. Baker believes the recovery could be even faster.

"I've seen guys coming back anywhere from 2 1/2 weeks to six weeks," Baker said. "I had surgery. The biggest thing is you have the wound heal. After that, it's a pain tolerance thing, and you're good to go."

"You have to have it removed," Baker said. "They take it out. There is no strengthening, no therapy. I don't say this lightly, but if you're going to break something in your hand, the hamate is going to be the way to go."

As a physician who does take care of patients who break bones on a regular basis, I figured I could discuss the injury a little bit and see what we can glean from it.

The Injury

The hamate bone is one of the hand's eight carpal bones at the base of the organ. It is a rare fracture when it comes to hand / wrist injuries, occurring in about two to six percent of all carpal fractures. For most people, the injury occurs due to a fall on an outstretched hand or direct blow to the palm. However, for athletes, that direct blow can occur with force transfer and grip on a swing of a club-like object, like a baseball bat or a tennis racket. The most commonly injured part o the hamate bone is the hook of the hamate.

You can see in the above X-ray where the hamate bone is. It is located at the base of the fifth metacarpal, which is the little finger. The injury results in pain in that area at the base of the little finger, and you can see how gripping a bat may cause such an injury.

As you hook the fingers around the bat and grip tightly, you can see how a swinging motion and possibly even contact with the bat can cause some force transfer that hits right on the bone. This is especially obvious at the hook of the hamate, where part of the flexor retinaculum (the cartilage sheath that covers the carpal tunnel on the palm side of the hand) attaches.

The injury presents as pain on that part of the hand, localized to the area of the bone. It can also have decreased grip strength and pain on grip, as Stanton showed during his subsequent plate appearances. Nerve injury to the ulnar nerve can also occur in fractures of the hook of the hamate, and those injuries are more urgently managed. Any injury that causes blood flow problems to the fingers immediately goes for operative management.

Management

It does not sound like Stanton's injury is severe in terms of nerve or blood supply problems. However, management of any fracture of the hamate bone generally follows some principals. All of these suspected injuries get X-rays to determine possibility of fracture. Commonly a fracture can be seen in a simple AP (front to back) view on X-ray.

If not, a "carpal tunnel" view with the hand and fingers outstretched is a possible way to evaluate fracture, especially of the hook of the hamate, which can be hard to see on a front to back view. If there are symptoms of an injury but no findings on X-ray, a CT scan can be done to confirm an injury.

Pain control and immobilization is achieved via splinting, which is a temporary form of casting with a hardened plaster segment on a certain part of the body wrapped by Ace bandages. The splint, usually put on the side of the little finger, usually keeps the hand still so that no further injury to the bone is made by movement.

In the past, these injuries could have been managed conservatively with casting and immobilization, but it has been found that this causes lack of rejoining of the bones. Now, the standard of care is to do surgical intervention. As mentioned by Baker, the usual method is to excise or remove the hook of the hamate. Removal of the hook removes the attachments of a few ligaments and muscles, so there is a concern for decreased grip strength in the future, but the alternative of open reduction and internal fixation of the bones shows no difference in grip strength.

After that, the patient undergoes physical therapy for recovery. It includes allowing time for wound healing and slowly rebuilding strength. Timing for recovery is different for individuals and depends on what level of activity is needed afterwards. Excision of the hook allows for immediate beginning of therapy, with a likely progression to full activities within six to eight weeks. Other surgical options involve casting for two weeks followed by physical therapy, making hook removal the best option for an athlete like Stanton.