Ye Xuan, Huang Dawei, Perriman Diana M, Smith Paul N
Department of Orthopedic Surgery, Australian Capital Territory Health, The Canberra Hospital, Canberra, Australian Capital Territory, Australia.
Prince of Wales Clinical School, The University of New South Wales, Sydney, New South Wales, Australia.
ANZ J Surg. 2019 Apr;89(4):320-324. doi: 10.1111/ans.14978. Epub 2019 Feb 12.
Tibial-plateau fractures with depressed osteochondral fragments have a high incidence of articular subsidence post reduction. Locking plates aim to prevent this via 'raft' screws below the subchondral bone. However, differences in plate design and patient anatomy result in variability of screw position in relation to the fragments they are designed to support. We evaluate the effect of screw placement and articular subsidence with this fracture pattern.
A retrospective cohort study of operatively treated tibial-plateau fractures with free osteochondral fragments was performed to determine if screw placement was correlated with articular subsidence. Primary outcome was the relationship between screw to joint distance and articular subsidence. Secondary outcomes were whether bicortical fixation, presence of bone graft, fracture characteristics and patient age was correlated with articular subsidence.
Sixty-eight of 309 tibial-plateau fractures had depressed osteochondral fragments (22%). The average thickness of these fragments was 10.2 mm. Fractures with raft screws placed closer to the joint than the thickness of the osteochondral fragment were less likely to subside (1.8 versus 3.4 mm; P = 0.02). The proportion of fractures with no radiographic subsidence was also greater in this cohort versus fractures with distal screw placement (33% versus 8%; P = 0.02). Articular comminution (P = 0.04) and female patients aged over 65 years (P = 0.03) were associated with increased articular subsidence.
Fractures fixed with screws closer to the joint than the thickness of the osteochondral fragment were correlated with less articular subsidence. The 'screw-joint distance' may help guide screw placement intra-operatively.
伴有凹陷性骨软骨碎片的胫骨平台骨折复位后关节下沉发生率较高。锁定钢板旨在通过软骨下骨下方的“筏”式螺钉来防止这种情况。然而，钢板设计和患者解剖结构的差异导致螺钉相对于其设计支撑的碎片的位置存在变异性。我们评估了这种骨折类型中螺钉置入与关节下沉的影响。
对接受手术治疗的伴有游离骨软骨碎片的胫骨平台骨折进行回顾性队列研究，以确定螺钉置入是否与关节下沉相关。主要结局是螺钉与关节距离和关节下沉之间的关系。次要结局是双皮质固定、植骨的存在、骨折特征和患者年龄是否与关节下沉相关。
309例胫骨平台骨折中有68例伴有凹陷性骨软骨碎片（22%）。这些碎片的平均厚度为10.2毫米。与骨软骨碎片厚度相比，筏式螺钉放置得更靠近关节的骨折下沉的可能性较小（1.8毫米对3.4毫米；P = 0.02）。与远端螺钉置入的骨折相比，该队列中无影像学下沉的骨折比例也更高（33%对8%；P = 0.02）。关节粉碎（P = 0.04）和65岁以上女性患者（P = 0.03）与关节下沉增加有关。
用比骨软骨碎片厚度更靠近关节的螺钉固定的骨折与较少的关节下沉相关。“螺钉-关节距离”可能有助于术中指导螺钉置入。
