Intra-articular Malunions: Complex Cases

Intra-articular Malunions: Complex Cases 19

Fig. 19.1 This 54-year-old man was seen 7 weeks after being treated for a radiocarpal and distal radioulnar joint dislocation sustained in a horse fall. The radial styloid fracture was treated with a percutaneous cannulated screw (closed), but a Henry volar approach had been used to place several bone anchors (most resorbable) to reattach the volar ligaments. A generous dorsal ulnar approach to reattach the triangular fibrocartilage was also performed.

He also sustained an ipsilateral elbow dislocation, which was treated open along with another external fixator. He was told he would need a wrist fusion in 3 months because a part of the joint had “disappeared” due to the severity of the impact. A Sauve-Kapandji procedure was also scheduled to improve the lack of pronation and supination.

On examination his wrist motion was blocked by the external fixator, and he had no pronation or supination, in part because his elbow had an external fixator removed 1 week before.

Fig. 19.2 Several major errors when dealing with this injury are worth discussing:

• Fragments never “disappear” in closed injuries; they are there, usually somewhere enmeshed in the metaphysis.

• A volar approach to reattach the volar ligaments is superfluous when there is a sizable styloid fragment present. As we have discussed several times, there is no tendency toward ulnar translocation when there is a sufficiently large radial styloid fragment, because it will contain the origins of the radioscaphocapitate (RSC) and long radiolunate (LRL) ligaments (see Chapters 10 and 18).

• The need for a bone anchor to stabilize the distal radioulnar joint may be debatable, but the location of the anchor is not: It is the fovea. The triangular fibrocartilage must be lax if the anchor is in the center of the head (as it was).

In my experience, major mistakes are not isolated. A bad result can be anticipated if the reconstructive surgeon satisfies the search at the most evident wrong spot, disregarding other potential areas of conflict, that later may become the main sources of pain and dissatisfaction. The wary reconstructive surgeon should question everything from previous surgery; studying is not always a strong point of surgeons who practice “haphazard” surgery. Furthermore, most surgical reports issued by such surgeons are useless, inaccurate, or overtly biased. Therefore, in principle, I do not pay any attention to the information reported. SRL, short radiolunate.

Fig. 19.3 Conversely, I find that the original radiographs, albeit imperfect, provide very useful information. In this case a radiocarpal dislocation and a sizable radial styloid fragment were evident in the radiographs. Despite the poor-quality images that could be obtained from the CT of the elbow (no wrist scan had been performed) the “disappeared” fragment can be found sunken in the metaphysis (arrow).

Fig. 19.4 In the preoperative CT sagittal images, important information was gleaned: The free osteochondral fragment (arrows) could be seen sunk into the metaphysis. Furthermore, a malunion of the radial styloid fragment could also be glimpsed by the excessive dorsal angulation in S2.

Fig. 19.5 In the coronal slices the malunion of the radial styloid fragment (about half of the scaphoid facet) could also be demonstrated. Note the different angulation between the radius in C2 and C3 (marked with dots) attesting to the concomitant dorsal collapse of the styloid fragment (yellow arrows). The sunken “disappeared” fragment is also evident in C4 (red arrows).