Costal osteo-chondral autograft in hand and wrist surgery

Abstract

Previous studies have described osteo-chondral costal vascularized autograft with a pedicled myo-osteous serratus anterior, a transverse rectus abdominis myocutaneous flap combined with vascularized costal cartilages and a case of vascularized osteochondral costal graft to replace the proximal pole of the scaphoid, partially successful. This study evaluates the feasibility of vascularized osteo-chondral costal autografts in the treatment of hand and wrist degenerative and post traumatic arthritis+ and describe the different types of possible grafts adapted to this specific indication. Sacrifice of the a rib cartilage to access the internal mammary vessels for breast reconstruction has become frequent and safe, with very few thoracic complications. This piece of cartilage resected and thrown away could be kept to reconstruct other deficient part of the body, with minimal complications. This study is based on thorax CT scans with intravenous contrast injection, wrist and hand CT scans, anatomic cadavers’ dissections data and information obtained in the literature. Random patients were included from the imaging software database of public hospitals of Marseille, we selected ten (five women and five men) normal thoracic injected CT- scans and ten normal hand and wrist CT-scans (five women and five men). Precise measures of ribs and carpal bones size and vessels’ (internal mammary arteries) position and size were taken on these scans. We then did dissections to put into practice the alternatives deducted from CT scans studies. The morbidity of previous costal vascularized autografts is important, and the vascularization not very reliable (based on anastomoses, secondary vessels). A myo-osteous flap implies a large and bulky tissue, which is difficult to manage in hand and wrist surgeries. Degenerative and post-traumatic arthritis of hand and wrist joints are still difficult to treat with generally bad outcomes, in certain situations other vascularized grafts (femoral condyle graft, iliac crest graft) are proposed. This work points out different possible safe sites of osteo-chondral costal vascularized autograft's harvest. These possible grafts have strong vascularization's reliability, large vessels’ caliber, long pedicle, and very low donor site morbidity. The third or fourth rib either cartilage only or osteo-chondral graft can be harvested on the internal mammary vessels (with direct branches to the periosteum). Another ideal location, even more for women (scar in the inframammary fold), is the sixth rib, more prone to cartilaginous harvest only, based on the musculo-phrenic artery.