gms | German Medical Science

Objectives/Interrogation: To evaluate the functional and radiographic results of a scaphoid excision and four-corner arthrodesis technique using percutaneous headless compression screws.

Methods: A cohort of 84 patients, mean age 45 (range, 20-66) years, was treated for SLAC 3 and SNAC 3. After scaphoid excision and removal of cartilage and subchondral bone in the midcarpal joint the DISI deformity was corrected. Luno-capitate fixation was achieved with two Herbert screws and triquetro-hamate fixation was done with one or two Herbert screws, always in a proximal to distal direction. Bone graft was never used.

Results: At a mean follow-up of 9 months (ranged from 3 to 24 months), 34 patients were reviewed (30 males and 4 females). Pain at rest and under load improved passing from 7 and 8 to 0 and 3 respectively, flexion-extension decreased from 83° (flexion 41° / extension 42°) to 54° (flexion 24° / extension 30°), grip strength increased from 20 to 21 kg, Mayo Wrist Score increased from 34 to 55. Radiological examination were done every months and CT-scan in some doubt case in which the consolidation was not clear. X-ray images demonstrated the consolidation of the luno-capitate arthrodesis in almost 2 months, the triquetrum-hamate arthrodesis reached the consolidation one month later. Some patients complaints discomfort in the ulnar side for almost 3 months. All patients return at previous work or status in 3 months but one. This case was reoperated for nonunion with the same technique using Herbert screw of bigger dimension and obtained healing in 2 months. No radiological osteochondritic/arthritis changes were observed at follow-up due to the lunate holes created by screws.

Conclusions: These results were comparable to or better than the results of previously published techniques in terms of fusion rates, alleviation of pain, grip strength, range of motion; Mayo wrist score. The technique showed the real advantages of strong compression for arthrodesis healing.