The anatomy and vascularity of the lunate: considerations applied to Kienböck's disease.

PURPOSE: The purpose of this study was to assess the anatomy and vascularity of the lunate. The genesis of lunatomalacia requires some combination of vascular risk and mechanical predisposition. The findings will be correlated with the major existing theories of the cause of Kienböck's disease. METHODS: We studied 27 cadaver upper limbs using latex injection and the Spalteholz technique. We investigated the blood supply to the lunate. In 24 wrists we evaluated the incidence and distribution of anatomic features, arthrosis, and soft tissue lesions. We correlated the lunate morphology and ligaments disruptions with the arthritic changes. RESULTS: The lunate morphology results as classified by Antuña-Zapico were five type I (20.8%), 18 type II (75%) and one type III (4.2%). The lunate was found to have a separate facet for the hamate in 11 cases (45.8%). The most common size of the facet was found to be 3 mm (range, 3-6 mm). Arthrosis was identified with most frequency in the radius (88.2%) and lunate (94.1%). The triangular fibrocartilage complex was found torn in 58.3%, the lunotriquetral interosseous ligament was torn in 20.8% and the scapholunate interosseous ligament (SLIL) was torn in 54.2% of the wrists. There was a correlation between the presence of arthrosis at the hamate and the presence of a lunate facet (P=0.027) and a correlation between the presence of a tear in the SLIL and arthrosis in the scaphoid (P=0.002). The nutrient vessels entered the lunate through the dorsal and volar poles in all the specimens. The dorsal intercarpal and radiocarpal arches supply blood to the lunate from a plexus of vessels located directly over the lunate's dorsal pole. Vessels entered the dorsal aspect of the lunate through one to three foramina. One to five nutrient vessels were observed entering the volar pole through various ligament insertions, including the ligament of Testut-Kuentz (radio-scapho-lunate (RSL) ligament) and the radiolunate triquetrum ligament (or dorsoradial carpal ligament) and ulnar lunate triquetral ligament. CONCLUSIONS: The lunate had consistent dorsal and palmar arteries entering the bone in all the specimens. The blood supply and foramina number is greater in the volar pole of the lunate than the dorsal pole. The lunate blood supply comes from different ligaments. In the etiopathogeny of Kienböck's disease it is possible that an acute or chronic, traumatic or non-traumatic injury of the vessel bearing ligaments, particularly because of their structure and the location of the RSL ligament, may have an important role in the appearance of lunate necrosis.

Monteggia fractures in adults. Review of 54 cases.

INTRODUCTION: We present a review of Monteggia fractures treated in our hospital between 1992 and 1998. PATIENTS AND METHODS: Fifty four patients with a Monteggia fracture were treated in our hospital with an average follow-up of 24 months (12-48 months). The average age was 41 years (18-81 years). According to the classification of Bado, there were 24 type I, 20 type II, 6 type III and 4 type IV. The etiology was in 27 cases a motor-vehicle and motorcycle accident, five a pedestrian struck by a car, 21 by a causal fall and only one by a direct hit by an iron bar in an assault. In 56% of the patients, the lesions were associated with polytrauma. In all the cases, treatment consisted of open reduction and internal fixation of the ulnar fracture using different methods of osteosynthesis (3.5 mm DCP, 3.5 mm reconstruction plates, 6.5 mm cancellous screw, tension band technique with Kirschner wires, and one-third tubular plates). Initial treatment of the radial head dislocation was attempted by closed reduction and verification under fluoroscopy. Subsequent open reduction and osteosynthesis were performed in 10 cases, and resection of radial head was necessary in three cases as the initial treatment. There were six open fractures with one case developing chronic infection. RESULTS: Results were evaluated according to the criteria of Anderson (union fracture, elbow and wrist flexion/extension). The results were excellent in nine patients (17%), satisfactory in 33 (61%), unsatisfactory in nine (17%) and failure in three (5%). Complications could be attributed to the severity of injury, type of fixation and errors in technique (four non-union, three failure of one-third tubular plates, one distal radioulnar instability) and to some features peculiar to this lesion (five nerve injuries, three redislocations of the radial head and four radioulnar synostosis). We needed to perform 14 reoperations to resolve some of the above mentioned complications.

Dorsolateral biplane closing radial osteotomy in zero variant cases of Kienböck's disease.

Twenty-six patients with Lichtman stages II and III Kienböck's disease had biplane dorsolateral radial closing osteotomy to reduce the radial inclination and dorsal angles on the sagittal plane. The effects of the procedure were studied clinically, radiologically, and by magnetic resonance imaging in a 2- to 6-year follow-up study (average follow-up period, 3.5 years). The signal intensity on T1- and T2-weighted images of the lunate increased after surgery in all patients, suggesting revascularization. The comparative advantages of this technique are discussed with regard to others currently used.

Contralateral median nerve autograft.

Interfascicular nerve autografting is a useful method to repair nerves with gaps, mainly if the removal of a nerve does not imply a defect to the donor area. Final results of peripheral nerve repair definitely depend on the size of the nerve gap, the level of the injury and the time elapsed from the time of injury until the nerve is repaired.