THE CASE
A 12-year-old girl presented to my office (JH) with bilateral wrist pain. She had fallen on both wrists palmar-flexed and then, while trying to get up, landed on both wrists dorsi-flexed. The patient did not hear any “pops,” but felt immediate pain when her wrists hyperextended. Hand, wrist, and forearm x-rays were negative bilaterally for fractures. She was placed in bilateral thumb spica splints.
At follow-up one week later, the patient reported 6/10 pain in her left wrist and 7/10 pain in her right wrist. The pain increased to 10/10 bilaterally with movement and was not relieved by icing or nonsteroidal anti-inflammatory drugs. On physical exam, there was bilateral swelling of the wrists without ecchymosis or erythema. The patient had limited passive and active range of motion, especially during wrist extension. She also had tenderness to palpation over the anatomical snuff box, extending proximally to the distal radius bilaterally. She had no tenderness over the ulna or metacarpals, no loss of sensation in any area nerves, and she was neurovascularly intact bilaterally.
Based on the mechanism of injury, undetected fracture or full thickness ligament tear were both possible. Because of this, and because magnetic resonance imaging (MRI) entails no radiation exposure, MRI was chosen for additional imaging of both wrists.
THE DIAGNOSIS
The MRI revealed bilateral, nondisplaced, extra-articular fractures extending through the scaphoid waist, with surrounding bone marrow edema. In the right wrist, the patient also had a low-grade partial tear of the membranous portion of the scapholunate interosseous ligament (SLIL) at the scaphoid attachment (FIGURE 1). In the left wrist, she also had a low-grade sprain of the SLIL without tear (FIGURE 2).
DISCUSSION
Carpal fractures account for 6% of all fractures.1 Scaphoid fractures are the most common carpal bone fracture among all age groups, but account for only 0.4% of all pediatric fractures.1-3 They’re commonly missed on x-rays because they are usually nondisplaced and hidden by other structures superimposed on the image.1,2,4 Undetected, scaphoid fractures can cause prolonged interruption to the bone’s architecture, leading to avascular necrosis of the proximal portion of the scaphoid bone.5,6
Bilateral scaphoid fractures are extremely rare and account for less than 1% of all scaphoid fractures.7 Very few of these cases have been published in the literature, and those that have been published have talked about the fractures being secondary to chronic stress fractures and as being treated with internal fixation (regardless of whether the fractures were nondisplaced or if the ligaments were intact).6-9
Our patient was placed in bilateral fiberglass short-arm thumb spica casts. We tried conservative treatment measures first because she had help with her activities of daily living (ADLs). At a follow-up visit 2 weeks later, we switched the casts to long-arm thumb spica casts because of the patient’s ability to pronate and supinate her wrists in the short-arm versions. After one month of wearing the long-arm casts, we placed her back in bilateral short-arm casts for 2 weeks. Eight weeks after the fall, we removed the short-arm casts for reevaluation.