A modified closed reduction maneuver restored alignment in an apparently irreducible volar distal radioulnar joint dislocation after computed tomography identified a bony locking mechanism, according to a case report published in Clinical Case Reports.
The report described a 34-year-old male physical education teacher whose left hand was dominant. He presented 20 minutes following a left wrist injury sustained while forcefully closing a door. Physical examination showed the wrist in slight pronation, restricted mobility, mild ulnar-sided swelling, and a dorsal ulnar depression.
Radiographs showed overlap of the distal ulna and radius. Computed tomography (CT) with 3D reconstruction confirmed a volar distal radioulnar joint (DRUJ) dislocation, with the ulnar head impacted against the volar rim of the radius in a pattern the researchers described as resembling a Hill-Sachs lesion. The analogy refers to a bony impaction defect creating a mechanical engagement point that can prevent standard reduction maneuvers.
Initial manual reduction in the examination room was unsuccessful. A second attempt following injection of 5 mL of local lidocaine into the wrist joint and DRUJ also failed. The patient then underwent manual reduction under intravenous anesthesia in the operating room. Two physicians first attempted reduction with traction and pronation, but the dislocation remained unreduced.
The researchers then used a three-physician maneuver informed by CT analysis of the locking mechanism. One physician applied proximal forearm traction, a second applied volar-to-dorsal pressure to the distal ulna, and a third applied distal wrist traction while fully pronating the wrist. The researchers emphasized that extreme pronation appeared to be the key unlocking step that disengaged the impacted ulnar head from the volar radial rim.
The mechanical block resolved immediately. Intraoperative C-arm fluoroscopy showed restored DRUJ congruency, although the fluoroscopic images were not saved. Following reduction, passive pronation and supination were fully restored. Postreduction Ballottement testing was positive, indicating residual DRUJ instability, and the wrist was immobilized in a neutral position with the elbow flexed to 90 degrees. The patient was advised to begin rehabilitation exercises 4 to 6 weeks following immobilization.
At 6 weeks, the patient reported mild discomfort with wrist movement, but pronation, supination, and flexion-extension had returned to normal, and the Ballottement test was negative. The researchers recommended regular radiographic follow-up, but the patient did not return to the outpatient clinic. A later telephone interview indicated that he remained asymptomatic, had full range of motion, and had returned to work without limitations.
The researchers noted that isolated volar DRUJ dislocations may be difficult to diagnose, particularly in emergency settings. They cited prior literature suggesting that up to 50% of cases may initially be misdiagnosed. They also noted that volar dislocations may be less conspicuous on standard imaging than dorsal dislocations, making physical examination findings particularly important.
The case report does not establish efficacy of the maneuver. The findings are limited by the single-patient design, lack of saved fluoroscopic images, absence of acute magnetic resonance imaging to assess soft-tissue injury, and lack of long-term in-person radiographic follow-up. The researchers noted that magnetic resonance imaging may be useful when persistent instability or soft-tissue interposition is suspected.
“In summary, the success of closed reduction for volar DRUJ dislocations hinges on early diagnosis, precise reduction mechanics, and effective immobilization,” wrote lead study author Jianlan Wang, of Central Hospital of Dalian University of Technology in Dalian, China, and colleagues. The researchers noted that the technique may provide “an alternative to open surgery in similar cases where the locking mechanism is identified as a bony impression on the ulnar head.”
The researchers reported no funding and no conflicts of interest.
Source: Clinical Case Reports
