75 Failed Reconstruction with Tenodesis: Chronic
75.1 Patient History Leading to the Specific Problem
A 36-year-old man presented to us complaining of pain and weakness in his left wrist. The patient had a fall on his outstretched hand 6 months prior to the consultation. He is a right-handed taxi driver with no other history of previous trauma. At the time of clinical examination, the patient had pain on the radial side of the wrist. Active range of motion (ROM) was almost symmetric to the contralateral side. Palpation was especially painful at the level of the scapholunate (SL) interval and scaphoid tubercle. Scaphoid shift test (Watson’s maneuver) and other specific test for SL instability were negative.
Radiological examination showed a flexed and pronated scaphoid and an increased SL joint space in the anteroposterior view, as well as an increased SL angle in the lateral view. No degenerative changes were seen. CT and Magnetic Resonance Imaging (MRI) confirmed these findings. Stress dynamic fluoroscopic examination showed a wider SL interval compared to the opposite side, especially in supination and ulnar inclination against resistance (▶Fig. 75.1).
Arthroscopic examination confirmed a complete rupture of SL primary stabilizers and insufficiency of secondary, with an easily reducible malalignment and with no cartilage wear, so a ligament reconstruction following the principles of the “three-ligament tenodesis (3LT) technique” was performed. A slip obtained from flexor carpi radialis (FCR) tendon is passed obliquely through the scaphoid from palmar to dorsal, emerging at the point of insertion of the dorsal SL ligament. The slip is then fitted in a trough created in the dorsum of the lunate, passed through a split made in the dorsal radiotriquetral ligament, and looped around. The scaphoid, lunate, and capitate are reduced and stabilized with two 1.5-mm Kirschner’s wires (K-wires) prior to tensioning and suturing the tendon graft onto itself. One wire is placed across the SL joint and one across the scaphocapitate joint (▶Fig. 75.2). Routine postoperative protocol, with immobilization for 6 weeks with a cast and K-wire removal 8 weeks after surgery, was followed.
75.2 Anatomic Description of the Patient’s Current Status
Eight months after surgery, the patient still had a painful wrist, with limited active ROM (80-degree extension/25-degree flexion) and weakness (10-kg grip strength in the operated side vs. 35-kg contralateral). Although intra- and postoperative carpal alignment was satisfactory, after removal of the K-wires, a progressive flexion deformity of the proximal row developed (▶Fig. 75.3). Functional views and dynamic fluoroscopic evaluation showed that it was a fixed malalignment. No images of arthrosis were seen in X-rays, CT scan, or MRI.
Fig. 75.1 (a, b) Wrist anteroposterior view showing increased scapholunate joint space, and scaphoid flexion and pronation. Increased scapholunate angle and dorsal displacement of the proximal scaphoid in the lateral view. These findings support the diagnosis of a static scapholunate dysfunction.
Fig. 75.2 The “three-ligament tenodesis reconstruction” used for chronic scapholunate instability without ulnar translocation of the lunate.
Fig. 75.3 (a, b) Symptomatic flexion malalignment of the proximal row 6 months after the “three-ligament tenodesis” procedure.
Several reasons may explain a flexion deformity of the lunate. Unrecognized lunotriquetral instability (e.g., as part of a perilunate instability) in which the surgical solution is focused just to solve an SL problem may end with a static palmar intercalated segmental instability deformity. Alternatively, flexion of the whole proximal row is associated with a dysfunction of the radiocarpal extrinsic ligaments, especially the dorsal radiocarpal ligament, as it happens in palmar midcarpal instabilities or in some operated distal radius fractures even with proper fracture reduction.
75.3 Recommended Solution to the Problem
Given that soft-tissue procedures are prone to fail when applied to a fixed carpal deformity, in those cases where some joint surfaces are still preserved and some degree of motion is desired, the treatment of choice is a partial carpal fusion.
Due to the abundant dorsal scar tissue and the fixed deformity, exploration of joint surface status was performed through an open dorsal approach. If possible, arthroscopic evaluation is preferred. The extensor retinaculum was divided again along the third compartment. This allows easy repositioning of extensor pollicis longus in its compartment after any intracapsular procedure is performed. The retinacular septa between the second and fourth compartments are sectioned and the two retinacular flaps so created are retracted. Dorsal fiber-splitting capsulotomy, as described by Berger and Bishop, was performed for the second time, with a wider extension toward the ulnar side in order to expose the triquetrum and triquetrohamate joint.
When exposed, the radiolunate joint was seen to be preserved, whereas chondral lesions were seen in the dorsum of both radioscaphoid and lunocapitate joints. Therefore, scaphoidectomy and midcarpal arthrodesis was performed.
To make scaphoidectomy easier, a small palmar approach can be done to release the scapho-trapezio-trapezoid and scaphocapitate ligaments, and the entry point of the FCR slip in the scaphoid. Reduction of lunate and triquetrum flexion deformity (volar intercalated segment instability) is the next step, in order to achieve a proper postoperative ROM (▶Fig. 75.4). Care has to be taken not to overcorrect the lunocapitate fusion, as too much ulnar translation of the distal row may create radial inclination of the wrist (▶Fig. 75.5). Finally, a midcarpal arthrodesis using three anterograde cannulated screws was performed. As in this case the lunocapitate joint was wide enough, two screws were placed between the lunate and the capitate, and one between the triquetrum and the hamate.
75.5 Postoperative Photographs and Critical Evaluation of Results
Ten years after the partial fusion, the patient is pain free, with mild discomfort when doing heavy work with the operated hand, and still working as a taxi driver. His active ROM is 50/50 degrees. Control X-rays at 10 years show no degenerative changes (▶Fig. 75.6).
75.6 Teaching Points
• The treatment of SL dissociations is stage dependent.
• A normally aligned wrist can be unstable.