Fig. 10.1 Intrinsic and extrinsic ligamentous injuries may coexist with a distal radial fracture, and the latter may have particularly devastating consequences. This is illustrated in the fracture shown here, which was treated at a time when the current thinking was that multiple fragmentation was a contraindication for arthroscopic surgery. As a further excuse, I should say that this case predated the introduction of the dry arthroscopic technique. The marginal fragments were too distal to be fixed by the latest fashion “Ti” plate and two additional screws (arrowheads) for the marginal lunate fragment were inserted. Despite a beautiful reduction, 4 months later the unhappy patient demonstrated ulnar translocation of the carpus. Understanding the pathophysiology of the injury may help to prevent this development.
Fig. 10.2 When the fracture occurs secondary to compressive and radial deviating forces, die punch and shearing fractures of the radius are expected. Similarly intrinsic ligamentous injuries may occur, whereas extrinsic ligaments tend to shorten and are rarely damaged. Conversely, in traction injuries, avulsion fractures of the radius occur. The traumatic forces may cause intrinsic or extrinsic ligament rupture or carpal fractures. These are potentially devastating injuries.
Fig. 10.3 Not only can these forces result in multiple injury types (a,b), but they can also cause major derangement of the DRUJ (c), which is discussed in this chapter.
Fig. 10.4 It is important to underscore that major damage to the RSC, LRL, and DRT ligaments will unavoidably cause ulnar carpal translocation. Several researchers have shown that unrecognized ulnar translocation is not salvageable past 8 weeks.
Fig. 10.5 The group lead by Min Jon Park have demonstrated that arthroscopic reduction and pinning without suturing the intrinsic ligaments can hold in the long term provided the bones are in anatomical position. In other words, if the carpus is held in reduction, the ligaments will heal and formal repair is unnecessary. Mark Henry presented a similar experience in my previous book on “Arthroscopic Management of Distal Radius Fractures.”
Keep in mind all the ligaments that can be injured concomitantly to the distal radius fracture represented in the illustrations. DRC, dorsal radiotriquetral; ECU, extensor carpi ulnaris; PRU, proximal and distal radioulnar; SC, scapho-capitate; SRL, short radiolunate; TC, triquetrum capitate; TH, triquetrohamate; UC, ulnocapitate; UL, ulnolunate; UT, ulnotriquetral.
Fig. 10.6 Be aware that about 25% of ligamentous injuries are missed on the initial radiographs! The wide girth of the wrist should alarm the clinician.
Fig. 10.7 These injuries present in young patients with high-energy trauma. The management with or without styloid injury is the same, although the prognosis is better for the former (Dumontier et al 2001). This is because the RSC and LRL ligaments remain attached to the styloid fragment, and with appropriate reduction there is no risk of ulnar carpal translocation.
Fig. 10.8 Reduction of the perilunate injury either occurs spontaneously by traction or is achieved easily by inserting a mosquito through the RMC portal and pushing on the lunate facet radially (see Video 10.1).
Fig. 10.9 After a preliminary arthroscopy the hand is placed on the table and an incision 1.5 cm slightly distal to the radial styloid (pointed by scissors) is performed. Blunt dissection with scissors, spreading the blades parallel to the neurovascular structures, avoids damage to the cephalic vein and the radial nerve on the path to the scaphoid.
Fig. 10.10 Always use a soft tissue protector for inserting the 1.25-mm K-wires. Dry arthroscopy prevents soft tissue infiltration and preserves the bony landmarks, but inserting the wires in the right spot is still not easy. I have found that inserting the K-wire just distal to the radial styloid and aiming for the ulnar styloid usually results in hitting the right spot in the lunate.
Fig. 10.11 This technique is demonstrated in an unrelated computed tomography (CT). Notice that the K-wire skips distal to the radial styloid and when aimed at the tip of the ulnar styloid will hit the scaphoid and lunate proximal to the midcarpal joint.
Fig. 10.12 Correct angulation of the first K-wire. This then provides a guide for the second K-wire, which can be angled more or less dorsally to catch a different part of the lunate. Insertion of two K-wires obviates the need to block the midcarpal joint at the end of the operation.
Fig. 10.13 Several fluoroscopic checks are needed until the K-wires are in the right place. If one K-wire is misplaced it is best to leave it in place until the next K-wire is inserted to prevent it from following the same path.
Fig. 10.14 Similarly, on the ulnar side, a single K-wire is inserted into the triquetrum (Tq). This is more easily achieved than the S-L wires. The K-wire is inserted with the hand in pronation, piercing the skin just dorsal to the pisiform and directed to the 3–4 portal. The orientation can also be checked by putting the wire over the skin and marking the intended direction with the aid of the fluoroscope.
Fig. 10.15 Once the surgeon is satisfied with the K-wire position, the hand is placed in traction. The joint is again irrigated and adjustments are made before the reduction proper proceeds.
Fig. 10.16 A Freer or similar instrument is used to direct the scaphoid into proper alignment. There are now three important technical considerations:
1. With the scope in the joint, reduce the traction of the hand to half or less (4–6 kg).
2. Push the scaphoid tubercle with the left hand to extend the scaphoid and compress the triquetrum, thereby closing the S-L space.
3. At the same time, push and reduce the proximal pole of the scaphoid with the Freer (or similar instrument from the RMC portal).
Fig. 10.17 I used to use a 1.6-mm K-wire introduced into the lunate as a joystick to reduce the lunate into volar flexion. I have noticed, however, that this dorsiflexion of the lunate is artificially caused by the scope. In an attempt to better visualize the reduction, the surgeon introduces the scope close to the S-L gap, on top of the dorsal aspect of the lunate. This causes the lunate to dorsiflex and prevents reduction. In this figure, the surgeon is pushing both the scaphoid tubercle and the triquetrum with one hand. At the same time the index finger supports the lunate K-wire in flexion (arrow) by pushing the K-wire in the lunate distally.
