Occult distal radial fractures

Predictive Power of Distal Radial Metaphyseal Tenderness for Diagnosing Occult Fracture

PURPOSE

To correlate the physical examination finding of distal radial metaphyseal tenderness with plain radiographic and magnetic resonance imaging after acute wrist injury to diagnose occult distal radius fractures. We hypothesized that persistent distal radial metaphyseal tenderness 2 weeks after acute injuries is predictive of an occult fracture.

METHODS

Twenty-nine adult patients presented, after acute trauma, with distal radial metaphyseal tenderness and initial plain radiographs and/or fluoroscopic images that did not show a distal radius fracture. Patients were reevaluated clinically and radiographically at approximately 2 weeks after initial presentation. Patients with persistent distal radial tenderness and negative radiographs underwent magnetic resonance imaging to definitively diagnose an occult distal radius fracture. We calculated the sensitivity and positive predictive value for persistent distal radial metaphyseal tenderness using a 95% confidence interval and standard formulas. Both radiographs and magnetic resonance imaging were used as our endpoint diagnosis for a distal radius fracture.

RESULTS

We diagnosed 28 occult distal radius fractures, 8 by follow-up radiograph and 20 by magnetic resonance imaging. The positive predictive value for patients who completed the protocol was 96%. One patient who did not have an occult distal radius fracture had a fracture of the ulnar styloid.

CONCLUSIONS

Tenderness of the distal radial metaphysis after wrist injury is strongly suggestive of a distal radius fracture despite both normal plain radiographs and fluoroscopic images.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

Functional limitation immediately after cast immobilization and closed reduction of distal radius fractures: preliminary report

The majority of research on distal radius fractures consists of retrospective, descriptive studies of patients with unstable fractures requiring fixation. The purpose of this investigation was to report on impairments in flexibility, grip strength, and motor control and on the presence of swelling and atrophy immediately after cast immobilization of closed reductions of simple distal radius fractures. Sixteen adult subjects from Kaiser Permanente Medical Center, San Francisco, entered the study, and 13 completed it. At the initial evaluation, upper extremity ranges of motion, grip strength, forearm circumferences, two-point discrimination, and motor reaction times were measured on the uninvolved side. The same measurements were taken on the affected side within 48 hours after cast removal. All but one subject worked throughout the casting period. There were significant postcasting impairments in forearm rotation (40% deficit in pronation and supination); wrist flexion, extension, and radial and ulnar deviation (50% reduction in all motions); grip strength (-32 kg, or approximately 24% of the strength of the unaffected side); and forearm circumference (-1.1 cm) and wrist circumference (+1.5 cm). Patients complained of awkwardness of the involved hand. These measured impairments immediately after immobilization of simple radius fractures were greater than the reported impairments in patients after reduction of radius fractures with fixation 6 to 27 months after injury. To prevent long-term disability and recover flexibility, strength, and function, patients with simple distal radius fractures should be referred to a hand, occupational, or physical therapist for evaluation, education, and treatment after immobilization. Longitudinal studies are needed to quantify long-term functional recovery with regard to the type of fracture and the degree of impairment measured immediately after casting.