PMC6451795_01
Injury radiographs. Obtained by urgent care on the day of injury. Radiology read stated no acute osseous abnormalities limited by patient positioning and pain due to decreased thumb range of motion. There is hyperextension present at the thumb MCP joint.
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The provider noted no dislocation or subluxation at the time (Figure 1).
CT scan obtained three weeks after injury. Workup by primary physician included an ultrasound, which was nondiagnostic, and then this CT scan on the same day. Images demonstrated dorsal subluxation of the thumb MCP joint with incarcerated radial sesamoid.
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At three weeks following her injury, a computed tomography (CT) scan obtained by her primary provider demonstrated dorsal subluxation of her right thumb MCP joint with entrapment of the radial sesamoid (Figure 2).
Closed reduction. The patient was referred to the Emergency Department where she was evaluated by orthopaedics and underwent insufflation of the MCP joint and closed reduction. The patient was noted to be unstable with greater than 10  of extension. The patient maintained in this splint for one week until first follow-up appointment.
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Her thumb was splinted in a reduced position at neutral flexion/extension (Figure 3).
MRI obtained three months after reduction. MRI obtained 3 months after reduction demonstrated rupture of the thumb MCP volar plate with intact radial and ulnar collateral ligaments.
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The MRI demonstrated a reduced MCP joint without soft tissue interposition, but it also demonstrated of a volar plate rupture (Figure 4).
Clinical photographs of the right thumb volar plate repair. (a) Image demonstrates retracted flexor tendon with suture tails exiting from suture anchor inserted into the thumb metacarpal. (b) Image demonstrates flexor tendons resting over the repaired volar plate.
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A Mitek micro anchor was used to repair the volar plate and secure it to the subcondylar fossa of the metacarpal (Figure 5).