Practicability of a locking plate for difficult pathologies of the scaphoid.

Abstract

Headless compressions screws are the most implanted devices for scaphoid fractures and nonunions. For cases when screw osteosynthesis is not possible, a special locking plate for scaphoid reconstruction has been developed. The purpose of this study was to evaluate the safety and practicability of this device for difficult scaphoid pathologies. Between March 2010 and December 2014, 20 patients (age range 16-59years) were treated with scaphoid locking plate osteosynthesis. In 17 cases it was due to scaphoid nonunion or delayed union and in three cases to treat a complex multi-fragmentary fracture of the scaphoid. Most of the initial fractures were located either in the proximal third (n = 9) or the middle third (n = 8) of the scaphoid. Mean follow-up was 14.6 ± 8.9months (range 2-30months). All three scaphoid fractures (100%) showed bony healing in the CT scan after 2.7 ± 0.6months. 15 of 17 (88.2%) patients with scaphoid nonunion demonstrated bony healing in the latest CT scan at an average of 6.2 ± 8.1months (range 2-11months) after scaphoid reconstruction. Range of motion (extension/flexion) was 104° ± 18.4° (range 80°-150°) and about one third less than the unaffected side. The average grip strength averaged 38.2kg on the operated side and 44.1kg on the unaffected side after surgery. 13 plates (65%) had to be removed due to impaction of the plate or protrusion of the screws. This new locking device for scaphoid reconstruction seems to be a safe, useful and reliable tool in the treatment of difficult nonunions or multi-fragmentary scaphoid fractures. The practicability is convincing and satisfying fusion rates can be accomplished. However, most patients require hardware removal. We recommend using this plate as a rescue option when a stable osteosynthesis is necessary for the healing process and screw fixation has already failed or is not possible.