Surgical approaches to the carpus

Osteolysis After Augmented Scapholunate Ligament Reconstruction: A Report of 3 Cases

CASE

Augmented scapholunate ligament reconstruction using polyether ether ketone anchors and ultra-high molecular weight polyethylene synthetic tape has the theoretical advantage of improved stability, avoidance of K-wire fixation, and the potential for earlier mobilization. We present 3 cases of scaphoid and lunate osteolysis/fragmentation, operative and histologic findings at reoperation, and the sequelae of this technique.

CONCLUSION

If planning to use suture anchors and synthetic tapes in small carpal bones, we recommend advising patients about the risk of osteolysis and monitoring closely patients who complain of pain with motion after surgery.

Is the Dorsal Fiber-Splitting Approach to the Wrist Safe? A Kinematic Analysis and Introduction of the "Window" Approach

PURPOSE

To compare the kinematic effects of the dorsal fiber-splitting approach for scapholunate ligament repair to a dorsal "window" approach that spares all ligaments.

METHODS

We randomized 24 fresh-frozen paired cadaveric forearms to either the dorsal fiber-splitting capsulotomy approach (FSC) or the dorsal window approach (window) following scapholunate interosseous ligament (SLIL) division. Loaded fluoroscopic radiographs were obtained after each of the 4 testing conditions following cyclic loading (200 cycles; 71 N): (1) intact SLIL, (2) SLIL-division, (3) surgical approach, and (4) closure. FSC specimens were randomly allocated to 2 subgroups for closure with either a suture anchor (n = 6) or a simple running suture closure (n = 6). Radiographic parameter measurements included the scapholunate gap, radiolunate angle, scapholunate angle, and dorsal scaphoid translation.

RESULTS

Following the FSC, there were significant alterations in all radiographic parameters when compared with the intact and SLIL-division conditions. The window approach did not result in significant changes in any radiographic parameter. When compared to the window approach, all radiographic parameters of the FSC approach were significantly altered. Following closure with suture anchors in the FSC group, radiographic parameters improved, whereas with standard closure they failed to do so. Despite anchor closure, dorsal scaphoid translation, radiolunate angle, and scapholunate angle all remained elevated compared with scapholunate-divided wrists.

CONCLUSIONS

The FSC produced significant changes in carpal posture under load, including scapholunate diastasis, dorsal intercalated segment instability, and dorsal scaphoid translation in SLIL-deficient wrists. The window approach preserved the critical dorsal ligament stabilizers and did not produce changes in carpal posture.

CLINICAL RELEVANCE

The FSC may create iatrogenic changes in carpal posture that cannot be fully corrected with standard or anchor closure. The window approach does not alter carpal posture and should be considered when performing surgical procedures on the scaphoid or lunate.

An Extensile Approach to the Radial Aspect of the Carpus: "The Link Incision"

The structures on the radial side of the wrist and thumb base can be approached by a longitudinal incision on the radial side of the wrist. However, longer longitudinal scars can be cosmetically unacceptable and can result in a scar contracture. It is preferable to curve longer incisions along the Langer's skin lines to achieve better scar characteristics. Curving the incision also enables an extensile approach and provides easy access to the thumb base, radial carpus, and radial wrist joint. We describe our approach as a "Link" between the most common approaches that surgeons are familiar with; the dorsoulnar approach to the thumb metacarpophalangeal joint for ulnar collateral ligament repair and the flexor carpi radialis approach for distal radial fracture fixation. The zone between these two incisions is not as frequently approached. Our incision connects these two well established incisions and we have described a step by step approach to this unfamiliar area. This "Link zone" overlies the thumb trapeziometacarpal joint, scaphotrapeziotrapezoid joint, and the radial styloid. It contains superficial branches of the radial nerve, first extensor compartment tendons, and the deep branch of radial artery in the anatomic snuff box. The "Link incision" is an extensile approach in both the proximal and distal directions.