Litrenta Jody, Tornetta Paul, Ricci William, Sanders Roy W, OʼToole Robert V, Nascone Jason W, Faber Henry, Wilson Darren
Boston University Medical Center, Washington University St. Louis, MO, Florida Orthopaedic Institute Tampa, FL, R Adams Cowley Shock Trauma Center, Department of Orthopaedics, University of Maryland School of Medicine Baltimore.
J Orthop Trauma. 2017 Mar;31(3):127-130. doi: 10.1097/BOT.0000000000000753.
To determine (1) the reliability of the standard and modified Radiographic Union Scale for Tibia fractures (RUST) score in a sheep osteotomy model, and (2) the standard and modified RUST scores that represent biomechanical union.
The tibia cortices in a sheep osteotomy model treated by intramedullary nails were radiographically evaluated using standard and modified RUST scores. Scores that correlated with biomechanical union, based on the torsional stiffness of the contralateral tibia, were determined.
Two groups of sheep had transverse midshaft osteotomies treated with 10-mm nails after reaming to 11.5 mm. Weight-bearing was allowed as tolerated. Anteroposterior and lateral radiographs were taken at standard intervals from 4 to 12 weeks. The tibial cortices at each time interval were evaluated in a random order by 5 senior orthopaedic trauma surgeons. Each tibia was scored using the standard and modified RUST methods and was assessed for union.
The intraclass correlation coefficient (ICC) was determined for standard and modified RUST scores at each time interval and for the assessment of union. The percentages of fractures that were defined as united by the surgeons were tabulated by RUST and modified RUST scores. The torsional stiffness of each tibia was tested at 12 weeks and expressed as a percentage of the contralateral side. We considered biomechanical union to be ≥90% of the torsional stiffness of the normal side.
The modified RUST score demonstrated consistently higher ICCs than the standard RUST. All reviewers considered a standard RUST of 10 and a modified RUST of 14 to represent radiographic union. The standard RUST was 10.4 (range: 8.6-12) and modified RUST was 14.2 (range: 12.2-16) for tibiae that were biomechanically united.
The modified RUST score has a slightly higher ICC than the standard RUST. A standard RUST of 10 and a modified RUST of 14 provide an excellent definition of union based on surgeons' opinion and biomechanical testing for a transverse fracture.
(1) 确定标准和改良的胫骨骨折影像学愈合评分量表（RUST）评分在绵羊截骨模型中的可靠性，以及 (2) 代表生物力学愈合的标准和改良RUST评分。
采用标准和改良RUST评分对髓内钉治疗的绵羊截骨模型的胫骨皮质进行影像学评估。根据对侧胫骨的扭转刚度，确定与生物力学愈合相关的评分。
两组绵羊行中段横行截骨，扩髓至11.5 mm后用10 mm的髓内钉治疗。允许根据耐受情况负重。在4至12周的标准间隔时间拍摄前后位和侧位X线片。5名资深骨科创伤外科医生以随机顺序对每个时间间隔的胫骨皮质进行评估。每根胫骨均采用标准和改良RUST方法评分，并评估其愈合情况。
确定每个时间间隔的标准和改良RUST评分以及愈合评估的组内相关系数（ICC）。按RUST和改良RUST评分列出外科医生定义为愈合的骨折百分比。在12周时测试每根胫骨的扭转刚度，并表示为对侧的百分比。我们认为生物力学愈合为正常侧扭转刚度的≥90%。
改良RUST评分的ICC始终高于标准RUST评分。所有评估者均认为标准RUST评分为10分、改良RUST评分为14分代表影像学愈合。生物力学愈合的胫骨，标准RUST评分为10.4（范围：8.6 - 12），改良RUST评分为,14.2（范围：12.2 - 16）。
改良RUST评分的ICC略高于标准RUST评分。基于外科医生的意见和横行骨折的生物力学测试，标准RUST评分为10分、改良RUST评分为14分可很好地定义骨折愈合。
