This paper presents a modification of previous work by Makino (JRM, 2000) using vascularized pedicled second metacarpal base bone grafts to reconstruct scaphoid non-unions in 7 patients over two years. The patients included 5 traumatic fractures, one transscaphoid perilunate dislocation, and one pathologic fracture. Two of the non-unions were post-operative following unsuccessful Herbert screw fixation. All fractures were at least 5 months old. Three patients had a proximal pole fracture pattern, and 3 exhibited AVN on MRI. The surgical approach used both dorsal and palmar incisions. A DISI deformity was provisionally corrected with K-wire joystick rotation to determine the size and shape of the bone graft. The pedicled graft was based on dissection of the dorsal radial artery from the anatomic snuffbox distally. The second metacarpal artery was identified and traced to the metacarpal base. The grafts had to be tunneled beneath the ECRL/B and EPL tendons to reach the volar incision for insertion into the non-union site. Fixation was achieved with K-wires, removed at an average of 12 weeks. DISI was corrected in all patients at an average follow-up of 12 months. Average range of motion (no statistical analysis is reported) was within an accepted functional flexion/extension arc, although no comparison with preoperative values is provided. Pain with activities persisted in 2/7 patients. All patients returned to their previous employment. There were no reported major complications in the series.
The authors cite the advantages of this technique being primarily related to larger vessel size than the more commonly used dorsal retinacular vessels from the radial artery, and the use of an associated second incision (palmarly) to better correct the collapse deformity of the scaphoid. Although the technique is adequately described and illustrated, the results suffer from a lack of relevant critical evaluation. Patient satisfaction was good or excellent in all but one patient. Interestingly, all patients returned to their previous employment. Grip strength appeared to approach the uninjured side in all patients. However, no comparison is made with preoperative values for range of motion or strength. Although pre- and post-operative radiolunate angles are reported and do appear to improve, no statistical analysis was performed to determine the validity of these measures in this sample population. The additional morbidity associated with the second incision and extensive dissection on the radial side of the wrist associated with tunneling the graft from dorsal to palmar are not addressed. Surely, this may affect the overall result when considering the best option from the other available sources for local vascularized bone grafts in the treatment of scaphoid non-union.
Journal of Reconstructive Microsurgery