Our weekly NFL report evaluates injuries to players of local (Patriots, Giants and Jets) or national interest with commentary by a sports orthopedic specialist from the Bone & Joint Institute at Hartford Hospital.  Sign up for automatic delivery to your inbox (click here and scroll to “Free email newsletters”).

Player: Carson Palmer, Arizona Cardinals quarterback.

Injury: Broken left arm. Though not yet confirmed, Palmer reportedly suffered an isolated ulna fracture in his left forearm.

How it happened: Palmer was hit by Rams linebacker Alec Ogletree while attempting to pass in the second quarter of the Cardinals’ 33-0 loss Oct. 22 in London.

Forearm fracture.
A forearm fracture of both the ulna and radius bones.

Expected time missed: Eight weeks is a standard guideline for this injury, but some speculate Palmer could return in 4-6 weeks depending on his recovery and how well the Cardinals play while he’s out. Some players miss little time because they can play wearing a cast — Carolina Panthers linebacker Thomas Davis played in Super Bowl 50 two weeks after suffering a similar injury — but that’s not an option for a quarterback.

It’s possible, however, that Palmer could meet the reduced timeline if he played wearing a splint. It’s also possible that if Palmer, 37, does not play the rest of the season, the London game was his last in the NFL.

Dr. Clifford Rios, Bone & Joint Institute orthopedic surgeon and board-certified in sports medicine: “Whether this ends his career depends on the location and complexity of the fracture,” says Dr. Rios. “A simple fracture pattern in the mid-portion of the ulna should heal and rehabilitate fully. A fracture near either end of the ulna can involve the motion and function around the elbow or wrist joint, and greatly affect motion and function here.”

What’s the ulna?: It’s one of the forearm’s two bones. Drop your arms to your side, palms facing outward. The bone closest to your body is the ulna. It’s longer and larger than the forearm’s other bone, the radius. (While maintaining that palms-out position, the radius is closest to your thumb.) The ulna is biggest at the elbow, the radius biggest at the wrist. Together, they give the forearm its rotational flexibility — that’s how you were just able to turn palms up or palms down.

Where’s the fracture?: Forearm fractures can happen near the wrist (distal), in the middle of the bone or near the top (proximal), near the elbow. It’s among the most common injuries in the NFL.

“A non-thrower can sometimes be treated in a cast or functional brace, depending on his position,” says Dr. Rios. “This would never work for a thrower.”

Players eventually return, but perhaps at some long-term cost: A Washington University (St. Louis) study published this year found that the careers of players who underwent surgery for a forearm fracture were shortened by one year and that they played in almost two fewer games a season than the “matched control” segment of the study.

Does that mean broken forearm bones do not heal the same way as, say, a broken collarbone?

“This depends on the forearm bone that is fractured,” says Dr. Rios. “The motion of the radius is more complex and any alteration of the anatomy to this bone can affect forearm function.  The ulna functions more like a hinge at the elbow and is not as involved with forearm rotation.”

In everyday life, arm fractures account for close to half of all broken bones in adults. (For children, collarbones and forearms are 1-2 in bone breaks.) The radius, because it’s weight-bearing, is the forearm bone fractured most often.

“It completely depends on the mechanism of injury, but we generally see radius fractures more often,” says Dr. Rios. “The ulna is more often fractured from a direct blow, whereas radius fractures, especially those closer to the wrist joint, are much more common with falls on an outstretched arm.”

Signs of a broken forearm: Sudden, extreme pain and, in severe cases, bone sticking out at the skin’s surface.

Treatment/Recovery: When a fracture is suspected, immediately put the arm in a sling and try to keep it immobile. If X-rays indicate the bones are not displaced, a cast will be required for 4-8 weeks. If the bones are out of place, they can be manipulated manually or through surgery. In surgery, the bones are pinned or plated together.

“Recovery is probably a little longer for the non-athlete,” says Dr. Rios. “Six to eight weeks is the earliest we could expect to see an athlete with most forearm fractures back on the field.”

If you break one or both of your forearm bones, expect some cryotherapy (cold-pack treatment), followed by 6-8 weeks in a hard cast. After such inactivity, you’ll need muscle-strengthening exercises for your forearm and wrist. Both areas will have at atrophied and lost strength. Your physical therapist will devise a program to strengthen every muscle related to the wrist joint. Wrist pain or stiffness caused by scar tissue could be treated with deep tissue massage.

Next, weight-bearing exercises using resistance bands or other exercises using your own weight, such as pushups, will help restore the forearm’s normal function.

“The biggest risk is too much stress too soon,” says Dr. Rios.  “Stressing a fracture too soon can lead to delayed healing, or complete failure of healing.”

Dr Clifford Rios, a sports medicine surgeon with Orthopedic Associates of Hartford, is Site Director for orthopedic resident education at the Bone & Joint Institute. Click here to find out why the Bone & Joint Institute is the athlete’s choice, with a Motion Lab for performance analysis, the area’s most comprehensive sports rehabilitation facility and 30 fellowship-trained orthopedic surgeons.