The role of rotational correction in proximal crescentic osteotomy : A retrospective comparative study R. Okuda 1) T. Yasuda 2), T Jotoku 2) H. Shima 2) T. Hida 2) M. Neo 2) 1) Dept. of Orthopaedic Surgery, Shimizu Hospital 2) Dept. of Orthopedic Surgery, Osaka Medical College
< The role of rotational correctionin proximal crescentic osteotomy: A retrospective comparative study> < Ryuzo Okuda> My disclosure is in the Final AOFAS Mobile App. I have no potential conflicts with this presentation.
Introduction Risk factors for postoperative recurrence of hallux valgus can be a round-shaped lateral edge of the first metatarsal head (a positive round sign) (arrowheads) and incomplete reduction of the sesamoids (arrow) after surgery. We newly devised a proximal crescentic osteotomy with rotational correction (PCO-R) in order to reduce these risk factors. The purpose of this study was to assess results of a PCO-R compared with a proximal crescentic osteotomy (PCO) and to clarify the role of rotational correction in PCO.
Patients Symptomatic moderate-to-severe adult female hallux valgus Group A : 105 pts (128 feet) 59 feet treated with a PCO between Jan. 00 and Jun. 07. Group B Age; 52 yr. (23 78 yr.) Duration of Follow-up; 31.3 mo. (12 48 mo.) 69 feet treated with a PCO-R between Jul. 07 and Aug. 11. Age; 57 yr. (20 83yr.) Duration of Follow-up; 29.9 mo. (12 53 mo.)
Surgical Technique A. Proximal Crescentic Osteotomy (PCO) 1. Release of distal soft tissue 2. Excision of the medial eminence 3. Proximal crescentic osteotomy The proximal fragment was moved medially (black arrow) and the distal fragment laterally (white arrow). 4. Plication of the medial part of the capsule B. PCO with Rotational Correction (PCO-R) 1. PCO with supination of the distal fragment (curved arrow)
Methods 1. AOFAS sacle 2. Pre- and postoperative dorsolpantar radiographs Hallux valgus (HV) angle Intermetatarsal (IM) angle Position of the medial sesamoid Grade I, II, III, IV, V, VI, and VII (Hardy method) Shape of the lateral edge of the 1 st metatarsal head Round, angular, and intermediate types (Okuda classification) 3. Recurrence of hallux valgus (HV angle 20 at the final follow-up)
AOFAS Scores and Radiographic Measurments Group A Group B p value AOFAS score Preop. 56.1 (44-72) 56.9 (33-78) 0.57 Postop. 92.5 (67-100) 95.6 (80-100) 0.04 HV angle ( ) Preop. 36.7 (22-56) 35.1 (21-60) 0.31 Posto. 12.3 (0-33) 10.1 (0-26) 0.10 IM angle ( ) Preop. 17.5 (10-24) 17.3 (11-27) 0.77 Postop. 7.8 (2-17) 7.8 (2-16) 0.98 Sesamoid position Preop 6.8 (5-7) 6.6 (4-7) 0.03 Postop. 4.0 (1-7) 3.2 (1-6) <0.01
Distribution of the Shape of the Lateral Edge of the 1 st Metatarsal Head Preop. Postop. Type R Group A 45 (76%) 16 (27%) Group B 51 (74%) 8 (12%) Type I Group A 10 (17%) 10 (17%) Group B 11 (16%) 13 (19%) Type A Group A 4 (7%) 33 (56%) Group B 7 (10%) 48 (69%) Round sign (+) Round sign ( ) Round sign ( )
Round sign and Recurrence of Hallux Valgus Group A Group B p value Round sign (+) Preoperative 76% 74% 0.92 Postoperative 27% 12% 0.04 Recurrence of hallux valgus 11/59 (19%) 3/69 (4%) 0.01 (21-33 ) (21-26 ) Chi- square test
Relation between a round sign and pronation of the 1 st metatarsal In most of normal feet, the round sign is negative (Fig. 1). On the other hand, the round sign is positive in most of hallux valgus feet. From an anatomical point of view, the lateral surface of the metatarsal head appears on the dorsoplantar radiograph when pronation of the 1 st metatarsal increases. The pronation of the 1 st metatarsal with hallux valgus may cause the round-shaped lateral edge of the 1 st metatarsal head (Fig. 2). Med. Fig.1 Neutral Lat. Med. Lat. Fig.2 Pronation
Role of Rotaional Correction of the 1 st metatarsal 1. Correction of pronation of the 1 st metatarsal can lead to lower prevalence of a positive round sign which can be a risk factor for recurrence of hallux valgus. 2. Correction of pronation of the 1 st metatarsal can lead to better reduction of the sesamoids because pronation of the 1 st metatarsal may be possible component of lateral displacement of the sesamoids which can be a risk factor recurrence of hallux valgus (Fig. 3) Facets Sesamoids Med. Neutral Lat. Med. Pronation Lat.
References 1. Eustace S et al. Radiographic features that enable assessment of first metatarsal rotation: the role of pronation in hallux valgus. Skeletal Radiol. 1993;22:153-156. 2. Kitaoka HB et al. Clinical rating systems for the ankle-hindfoot, midfoot, hallux and lesser toes. Foot Ankle Int. 1994;15:349 353. 3. Mann RA et al. Repair of hallux valgus with a distal soft-tissue procedure and proximal metatarsal osteotomy. J Bone Joint Surg Am. 1992;74:124 129. 4. Okuda R et al. The shape of the lateral edge of the first metatarsal head as a risk factor for recurrence of hallux valgus. J Bone Joint Surg Am. 2007;89:2163-2172. 5. Okuda R et al. Postoperative incomplete reduction of the sesamoids as a risk factor for recurrence of hallux valgus. J Bone Joint Surg Am. 2009;91:1637 1645. 6. Shima H et al. Radiographic measurements in patients with hallux valgus before and after proximal crescentic osteotomy. J Bone Joint Surg Am. 2009;91:1369 1376.
背景 外反母趾術後の変形再発の危険因子 1. 円形の第これらの危険因子の原因は 1 中足骨頭外側縁 (round 第 1 中足骨の回内変形の遺残徴候陽性 ) 2. 第母趾種子骨の整復不良 1 中足骨の回外方向への矯正も加えた近位中足骨三日月状骨切り術を考案
目的 従来の近位中足骨三日月状骨切り (PCO) とこれに第 1 中足骨の回外方向への矯正も加えた術式の X 線成績を比較することにより 第 1 中足骨の回旋矯正の意義を明らかにする
対象 従来群回旋矯正群 p 値 年齢 55 歳 57 歳 0.06 術後経過観察期間 31 か月 30 か月 0.47 Follow-up 率 84% 95%
1. 内側関節包切離 内側骨隆起切除 2. 母趾内転筋腱切離 深横中足靭帯切離 3. 背外側関節包切開 4. 近位中足骨ドーム状骨切り 内反の矯正 術式 K 鋼線による内固定 5. 内側関節包縫縮回外方向に矯正
X 線評価 荷重位足背底像外反母趾角 (*:HV 角 ) 第 1- 第 2 中足骨間角 (#: M1-M2 角 ) 種子骨偏位度 (Hardy 分類 ) * #
X 線評価 荷重位足背底像第 1 中足骨頭外側縁の形状 Round 徴候陽性 角型 中間型 円型 Okuda et al JBJS-A, 2007
術 前後の X 線計測 従来群 回旋矯正群 p 値 HV 角 ( ) 術前 36.7 35.1 0.20 術後 12.3 10.1 0.30 M1-M2 角 ( ) 術前 17.5 17.3 0.62 術後 7.7 7.6 0.30 種子骨偏位度術前 6.9 6.6 0.06 術後 3.8 3.2 0.03 Mann-Whitney U test
術 前後の第 1 中足骨頭の形状分布 術前 術後 円型従来群 76% 27% 回旋矯正群 74% 12% 中間型従来群 17% 17% 回旋矯正群 16% 19% 角型従来群 7% 56% 回旋矯正群 10% 69%
術 前後の round 徴候 Round 徴候 (+) 従来群回旋矯正群 p 値 術前 76% 74% 0.92 術後 27% 12% 0.04 χ 2 検定
術後の変形再発 (HV 角 20 ) 従来群回旋矯正群 p 値 変形再発 11/59 (19%) 3/69 (4%) 0.01 (21-33 ) (21-26 ) χ 2 検定
外反母趾と第 1 中足骨回内との関係 A. Cadaveric Study 1. Eustace et al. (Skeletal Radiol, 1993) 2. Dayton et al. (J Foot Ankle Surg, 2014) B. Clinical Study 外反母趾と第 1 中足骨回内には有意な関係 外反母趾手術では回内変形の矯正も考慮 1. Okuda et al (JBJS-Am, 2007) 回内変形を矯正する本術式を考案 2. Mortier et al (Bone Joint Research, 2012)
第 1 中足骨近位三日月状骨切り術従来法 vs 回内矯正法 Round 徴候陽性率従来群 > 回旋矯正群 第 1 中足骨遠位骨片の回内矯正 種子骨偏位度従来群 > 回旋矯正群 は術後の変形再発を減少させる 変形再発率従来群 > 回旋矯正群
第 1 中足骨回内の矯正効果 1. 再発危険因子である Round 徴候を陰性化 回内位 外反母趾 中間位
種子骨の外側偏位を改善 第 1 中足骨回内の矯正効果 2. 再発危険因子の種子骨偏位を改善 中足骨の回内変形により種子骨関節面も回内 種子骨を整復しても正常に比して外側偏位が遺残 外側 中足骨を回外方向に矯正 種子骨関節面の傾斜が正常化
まとめ 1. 外反母趾に対する PCO とこれに第 1 中足骨の回内矯正を加えた骨切り術の X 線成績を比較した 2. 術後 回旋矯正群の方が有意に round 徴候陽性率が低下し 種子骨偏位が改善し 変形再発率も低下した 3. 第 1 中足骨の回内矯正は変形再発を減少させる