SURGICAL TECHNIQUE
Either a 1-cm to 2-cm transverse incision distal to Lister’s tubercle or a longitudinal incision just ulnar was utilized. The extensor pollicis longus was identified and retracted. A longitudinal or an L-shaped capsulotomy was made to identify the proximal pole of the scaphoid. With the wrist flexed, a guide wire was inserted down the central axis of the scaphoid and confirmed by fluoroscopy. The measurement was made off the guidewire and 4 to 6 mm was subtracted. The scaphoid was then drilled, and the variable pitch compression screw (Acutrak Headless Compression Screw, Acumed) was inserted. Compression and position of the screw were confirmed by fluoroscopy before closure.
RESULTS
A total of 23 patients (19 males, 4 females) with acute scaphoid fractures who were treated conservatively with casting for at least 12 weeks and ultrasound stimulation, and progressed to delayed unions or nonunions were identified in this study. The ages of the patients ranged from 19 to 50 years. Of the 23 patients, 6 were smokers. The majority of patients sustained fractures in the scaphoid waist (18 patients) (Figure 1). Two patients had distal third fractures, and 3 had proximal third fractures.
The average time from the sustained injury to the surgical intervention was 8.2 months (range, 3.1-27.6 months). There were no patients with delayed diagnoses. Three fractures were identified as delayed unions with failure of union and pain after 3 months of conservative treatment, whereas the other 20 were identified as nonunions with at least 6 months of failed conservative treatment.
Of the 23 patients, 21 were found to have centrally placed variable compression screws based on Trumble and colleagues’8 criteria. Of the 23 patients, 19 had a complete follow-up course with radiographs at 6 months after surgery. All of these 19 patients had evidence of radiographic union defined as bridging trabeculation with near or complete obliteration of the fracture line on PA, lateral, and scaphoid radiographic views (Figure 2). Of the 6 smokers, 5 progressed to radiographic union and 1 patient had <6 months of postoperative return visits and could not be contacted. At the final clinic visit, all of the 19 patients denied wrist pain on direct palpation over the scaphoid tubercle, and no complications were reported. There were no repeat or revision surgical interventions.
Four patients had limited follow-up with <6 months of postoperative return visits. Their final set of radiographs did not demonstrate complete bridging trabeculation. One patient who moved away from the area was lost to follow-up but was contacted. The patient stated that he had a pain-free wrist with no further surgical interventions on his scaphoid. The other 3 patients could not be contacted.
DISCUSSION
The management of scaphoid nonunions and delayed unions has dramatically evolved over the past 20 years.1,3-8 Historically, semi-rigid stabilization using Kirschner wires and casting afforded a 77% union rate in these cases.9 More recently, several authors have reported that stabilization without bone grafting can predictably unite scaphoid nonunions. Treating patients with uncomplicated scaphoid nonunions and delayed unions by internal fixation alone may be all that is required to achieve union.
The definitions of a scaphoid nonunion and delayed union are complex. The exact time when a scaphoid fracture heals varies between patients.2,5,10 However, the majority of hand surgeons believe that failure to see clear signs of healing (in waist fractures) after 3 months from the injury would suggest a failure to heal and a “delayed” union, whereas failure after 6 months from the injury and without clear signs of healing indicate a nonunion.5,6,10,11 Any resorption at the fracture site suggests that the fracture will not heal by continued immobilization alone and will require surgery.10
Continue to: Hand surgeons have several surgical options...