Hand CASE 12

CASE                               12                               

A 24-year-old, law student injured her left index finger during a volleyball game and developed immediate pain and deformity. By her description, this deformity occurred at the level of the PIP joint. Courtside, one of her colleagues immediately pulled on the finger, and she presents to your office 3 days later. Clinically, she has a swollen finger, but there is no obvious deformity. Radiographs are shown in Figure 4–10A and B.

 

 

Figure 4–10 A–B

 

The most likely diagnosis is which of the following?

1. Condylar fracture of the proximal phalanx

2. Fracture dislocation of the PIP joint

3. Shaft fracture of the proximal phalanx

4. Bony avulsion of the flexor digitorum superficialis

 

Discussion

The correct answer is (A). Radiographs show a unicondylar fracture of the proximal phalanx, in this case involving the ulnar condyle. The condyle is displaced, and there appears to be an articular stepoff. The patient’s description of the injury and deformity are consistent with what could have occurred at the time of the injury, and the displacement at the time of injury may have been more significant than that being noted on the radiographs at this time.

The most appropriate form of treatment at this time would be which of the following?

1. Closed reduction and buddy taping to the middle finger

2. Closed reduction and placement of the index finger in a volar splint allowing the patient DIP motion

3. Closed reduction and percutaneous pin fixation of the proximal phalanx

4. Open reduction and internal fixation of the proximal phalanx

5. Either C or D

 

Discussion

The correct answer is (E). This is an unstable injury as evidenced by the patient’s description of the deformity at the time of injury and by the radiographs seen in the office. The fracture is displaced and is an intra-articular fracture. There is an articular stepoff. Furthermore, it is an oblique fracture. All of these features indicate that this is an unstable injury, and treatment by closed means is unlikely to be successful. In fractures that are completely nondisplaced, closed nonoperative

treatment remains an option. However, in this instance where there is articular stepoff and displacement has occurred, it is vital to restore the length of the fragment, and more critically restore articular congruity especially in this young person. Closed reduction and percutaneous fixation as shown in the postoperative radiographs can be effective if perfect reduction of the joint is achieved (Fig. 4–10C to E). Failure to achieve perfect joint reduction by closed means necessitates an open reduction and treatment with either pins or screws.

 

 

 

Figure 4–10 C–E

 

Should open reduction and internal fixation of this joint be performed, which of the following are likely complications?

1. Dysvascularity of the displaced condyle

2. Stiffness of the proximal interphalangeal joint

3. Stiffness of the DIP

4. Both A and B

5. All of the above

 

Discussion

The correct answer is (C). Irrespective of which treatment is utilized in this instance, it is almost always safe to allow the patient gentle range of motion of the DIP joint. Therefore, stiffness of the DIP joint is usually not a concern in these injuries. However, during open reduction internal fixation of this injury it is vital to maintain the attachment of the collateral ligament to the fractured proximal phalanx condyle. The vascularity of the head of the proximal phalanx is achieved through this attachment of the collateral complex. Therefore, any injudicious handling of this soft tissue attachment of the proximal phalangeal fragment, in an attempt to restore perfect radiographic anatomy, will inevitably lead to dysvascularity of this fragment and avascular necrosis with passage of time. Despite judicious handling of this fragment, it is not uncommon for the patient with this injury after open reduction internal fixation to develop stiffness of the PIP joint. Therefore, every attempt is made to achieve radiographic perfection without disturbing the soft tissue envelope by using percutaneous pinning techniques to achieve radiographic anatomical perfection, especially at the joint.

 

Objectives: Did you learn...?

 

 

Describe the radiographic features of condylar fracture of the proximal phalanx? Treat these fractures?

 

Pinpoint complications of open reduction and internal fixation of these fractures?