Free-Vascularized Medial Femoral Condyle Bone Transfers in the Treatment of Scaphoid Nonunions

Author(s): Jones DB, Moran SL, Bishop AT, Shin AY

Source: Plast Recon Surg 125(4):1176-1184, 2010.

Summary:

Scaphoid nonunions present a difficult challenge.  This retrospective case series involves 12 scaphoid nonunions with carpal collapse treated with vascularized medial femoral condyle cortico-cancellous grafts which all healed on average by 13 weeks.  Lateral interscaphoid angle, scaphoid height to length ratio, scapholunate angle, and radiolunate angles were all significantly improved after grafts were shaped to fit the defect and placed from a volar approach.  Carpal height ratios were unchanged after grafting.  All patients went on to heal and were followed for an average of 37 weeks.  Grip strength and range of motion improved in all patients. Two patients required bone stimulation to complete healing. Graft harvest technique was reviewed as well as donor site morbidity which was minimal.

The authors present their modification of the use of the free vascularized medial femoral condyle bone graft as originally described by Doi et al. for treatment of scaphoid nonunions.  They used the technique only for those nonunions with carpal collapse, instead preferring the more traditional 1,2 intercompartmental supraretinacular artery vascularized bone flap to be used for nonunions without collapse.  The benefit of the medial femoral condyle free flap is that more bone can be harvested with cancellous bone of high density that can be more easily molded and shaped to help correct humpback deformities and correct scaphoid length discrepancies.  It is unclear if this free tissue transfer requiring microsurgery and violation of the knee will achieve widespread support and use.