Management of fractures and non-unions of proximal scaphoid pole using theHerbert mini screw

32 patients, aged 16 to 49 years, were treated by osteosynthesis using the Herbert mini screw. The indications were five fractures (type B3, Herbert c lassification), two delayed unions (type C) and 25 nonunions (type Di to D3 , Filan and Herbert classification). Six patients received no bone grafts, 19 received cancellous bone graft from the radius. An interpositional iliac crest bone graft was used in four, and a vascularized bone graft from the distal radius in three cases respectively. The average postoperative immobi lisation in a forearm splint was nine weeks. 26 patients could be recruited for clinical follow-up at an average of 14,5 months. The radiological resu lts were assessed in 30 cases (94%). Bony consolidation was achieved in 26 cases (100% of the fractures, 84% of the nonunions). In three cases a loosening of the screw, and in three furth er cases a dislocation into the radiocarpal joint were observed. A humpback deformity was present in four cases. Three patients showed a persisting no nunion, one patient a fibrous union. Early degenerative changes of the radi ocarpal joint were observed in six cases. The clinical follow up examination showed an average grip strength of 91% ( JAMAR II), 94% for the three finger, and 95% for the pinch grip compared to the contralateral side. The mean postoperative pain score on the visual an alog scale was one for resting conditions, eleven for motion and 33 under s tress. The range of motion was 79% of the opposite side for extension/flexi on and 83% for radial/ulnar deviation. The average DASH-score reached 15 po ints. The Herbert mini screw has proven to be a reliable implant for reconstructi on of proximal pole fractures and nonunions of the scaphoid.