頚椎前方固定術における移植骨採取法―腸骨内側半層骨採取は術後の採骨部痛を軽減する

Technique for Bone Graft Harvesting from the Anterior Iliac Crest for Anterior Spinal Decompression Surgery : Donor Site Pain is Redeced by Bicortical Split-Thickness Harvesting from the Medial-Superior Aspect of the Ilium

　抄録：頚椎前方固定術における腸骨移植骨採取の合併症につき，全層骨および内側半層骨採取の2群に分けて検討した．症例全体をみると，術後の採骨部痛は全層骨採取法の40.5％，内側半層骨採取法の38.5％に生じ，うち術後2週間を越える痛みは全層骨採取法の16.2％，内側半層骨採取法の7.7％であった．採骨部痛を生じた例のみをみると，全層骨採取法の66.7％で痛みが6日以上継続したのに対し，内側半層骨採取法の80％で痛みが5日以下で止まっていた．以上，内側半層骨採取法は全層骨採取法と比べ，術後の採骨部痛を軽減する効果のあることがわかったが，その理由としては腸骨外側に強固に付着する筋肉を温存できることが考えられた．腸骨が十分な厚みを有しているときは，腸骨内側半層骨採取法においても十分量の移植骨を採取でき，術後の採骨部痛の軽減と併せ，よい方法であると思われる．

　Morbidity due to bone graft harvesting from the anterior iliac crest was retrospectively analyzed in patients who underwent anterior spinal decompression (Smith-Robinson method). Tricortical full-thickness grafts were harvested in 74 cases, and bicortical split-thickness grafts (inner table graft) was taken in 13 cases. The rate of perioperative donor-site pain was 40.5％ in the tricortical full-thickness bone graft group and 38.5％ in the bicortical split-thickness bone graft group. Subacute pain persisting for more than two weeks occurred in 16.2％ and 7.7％, respectively, of the groups. The rates of complications serious enough to interfere with daily activity were 1.4％ and 0％, respectively. Among the patients who complained of postoperative donor-site pain, 66.7％ of those in the tricortical full-thickness graft cases complained of subacute pain that persisted for 6 or more days, compared with 20％ in bicortical split-thickness graft groups. The bicortical split-thickness graft technique (inner table graft) seems to reduce the donor-site pain more effectively than the tricortical full-thickness graft technique. The reason is thought to be that sparing the tight muscle attachment to the lateral cortex results in fewer ambulation problems postoperatively. In addition, preserving the unilateral cortex of the crest reduces pelvic instability and lessens pelvic pain. When the pelvis is sufficiently thick, thie bicortical split-thickness grafting technique can provide ample cortical and cancellous bone with less donor-site pain. Moreover, the graft has two cortices connected at right angles, and the intensity is thought to be relatively well preserved.