Ulnar Fractures

Fig. 12.1 Currently, plating is the standard method for dealing with a concomitant ulnar fracture. Unfortunately, I have never seen a happy patient with one of the available ulnar plates—until after its removal!

Fig. 12.2 Swelling, extensor carpi ulnaris tendonitis, and pain are common complications that may necessitate hardware removal 6 months to 1 year after the initial fracture. Secondary operations are not without problems and require more time off work, the nuisance of returning to the operating room, further hand therapy, and an unhappy patient until the plate is taken out.

Fig. 12.3 To overcome the problems associated with conventional plating, I use two different strategies depending on the fracture location:

1. Cannulated screws

2. Low-profile plates and/or double plating

This chapter describes the management of scenarios from triangular fibrocartilage complex tears to shaft fractures.

Fig. 12.4 Pogue et al (1990), in Viegas’s laboratory, demonstrated that it was impossible to have shortening of the radius of more than 2 mm or 20 degrees of dorsiflexion without complete detachment of the TFCC from the fovea or the sigmoid notch. Hence, in principle, all distal radius fractures that are displaced enough to require surgery have an unstable distal radioulnar joint (DRUJ). However, by no means does this imply that all of them need to be operated on for distal radiolunar joint instability, thanks to the integrity of the secondary stabilizers. Primary stabilizers are highlighted in red. DDL, deep dorsal ligament; DPL, deep palmar ligament; ECU, extensor carpi ulnaris; SDL, superficial dorsal ligament; SPL, superficial palmar ligament; UCL, lunocapitate ligament; ULL, ulnolunate ligament; UTL, ulnotriquetral ligament.

Fig. 12.5 The secondary stabilizers (green), the ulnocarpal ligaments, ECU subsheath, and distal oblique bundle, also play a major role when the primary stabilizers are torn, to the point that in my practice the need for TFCC repair is rare in the setting of distal radius fractures.

Fig. 12.6 In my experience, relying only on arthroscopic findings will boost the number of patients who require ulnar-sided surgery. For this reason, as recommended by Jesse Jupiter, I test for instability after fixation of the radius. I only treat those which are unstable in radial deviation, irrespective of the arthroscopic findings. The test is done with the hand in neutral position, with the hand pointing to the ceiling and without traction (see Video 12.1). Typically, the DRUJ is somewhat unstable when the ballottement is done in ulnar deviation and stable in radial deviation. In radial deviation the secondary stabilizers come into play and act as a restraint to ulnar hypermobility.

Fig. 12.7 Some injuries are more prone to instability (red) than are others (green). As in the former injuries, both primary and secondary stabilizers may be torn. Specifically, most TFCC injuries that I see during arthroscopy are inconsequential and I leave them untreated (green). However, the “yellow” paths of injury are often unstable and might require surgical treatment. I always operate on red injuries. I must admit that my practice is biased toward young, active patients, so I am very keen on operating to avoid secondary problems. On the other hand, after age 65 years there is still a lot of life ahead, so most of the “older” patients in my practice deserve the same approach.

Fig. 12.8 I should emphasize again that the most common cause of DRUJ instability is insufficient reduction of the radius, particularly “radial translation” (see Figs. 2.16–2.18). This is so because the secondary stabilizers of the DRUJ become loose. Paying attention to the radius position will correct most cases of intraoperative DRUJ instability.

Fig. 12.9 Depending on the location of the fracture to the ulna and the type of fixation required, I may use any of the following approaches:

• Ulnar styloid approach (red): for ulnar styloid fractures

• Foveal approach (blue): for TFC detachments and fractures of the head

• Ulnar head approach (ECU–EDM) (blue): for neck and head fractures

• Dorsal-ulnar approach (ECU–FCU) (green): for distal shaft

Fig. 12.10 Ulnar styloid approach. A small incision ulnar to the 6R portal will direct the surgeon to the tip of the ulnar styloid, provided the wrist is in supination. Fractures of the base of the ulnar styloid are amenable to this limited approach. Only those that include the fovea are unstable and need to be addressed. A temporary K-wire or a bone hook is needed to keep the styloid reduced.

Fig. 12.11 This fracture of the base of the ulnar styloid that includes the fovea brings into question the stability of the DRUJ.

Fig. 12.12 After distal radius volar plating, the ulnar attachments of the TFCC were examined arthroscopically. With the arthroscope in 3–4 and the probe under the TFC, a positive hook test was demonstrated (i.e., the TFC was lifted with the probe and touched the lunate) (black arrows). The ulna was also somewhat hypermobile in radial deviation. Given that there was a large bony fragment, the patient was amenable to minimally invasive fixation of the styloid, which provides a stable reduction (see Video 12.1).

Fig. 12.13 Through a small incision, the ulnar styloid was reduced and temporarily fixed with two K-wires, one in the axis of the styloid and the other to prevent rotation of the fragment.

Fig. 12.14 For this indication I use self-tapping and self-drilling headless screws, usually 2.0 mm in diameter. Specifically, I am familiar with the Autofix™ brand distributed by Stryker (I underline that I have nothing to disclose). I find continuously threaded screws dangerous in this scenario. US, ulnar styloid.

Fig. 12.15 After fixation of the styloid the joint was again explored. This time the TFC was stable and the hook test was negative (see Video 12.1).