Occult Intertrochanteric Extension in Isolated Greater Trochanteric Fracture on Plain Radiographs
WY Wong, PY Chu, WCS Chan, TW Yeung, MK Yuen
Hong Kong J Radiol 2016;19:28-34
DOI: 10.12809/hkjr1615331
Objectives: To review the prevalence of occult intertrochanteric extension and fracture pattern in patients with isolated greater trochanteric (GT) fracture on plain radiographs.
Methods: Between January 2010 and December 2013, patients with trochanteric hip fracture at a regional hospital in Hong Kong were retrospectively reviewed. Those with isolated GT fracture on plain radiographs were included. The demographic details, premorbid condition, computed tomography (CT) findings, fracture pattern, surgical intervention, outcome, and follow-up radiographs were analysed.
Results: Of 928 patients with trochanteric fracture, 58 (6.3%) showed isolated GT fracture on plain radiographs. CT was performed in 51 (87.9%) patients: 10 (17.2%) had intertrochanteric extension, and 7 of them were offered operative fixation. Dynamic hip screw was inserted in five, and surgery was avoided in two who were considered having a high anaesthetic risk. For the fracture pattern of greater trochanter on CT, 29 (56.9%) showed more than one facet involvement. Most involved the superoposterior facet (39/51, 76.5%), followed by anterior facet (25/51, 49.0%), lateral facet (15/51, 29.4%), and posterior facet (12/51, 23.5%). In the intertrochanteric extension group, there was a higher proportion of anterior facet involvement (Fisher’s exact test, p = 0.038; odds ratio = 5.65 [95% confidence interval, 1.06-30.0]) and lower proportion of superoposterior facet involvement (p = 0.042; odds ratio = 0.21 [95% confidence interval, 0.047-0.91]). There was no statistically significant difference in the posterior and lateral facet involvement, or the age and gender in both groups.
Conclusion: In patients with isolated GT fracture on plain radiographs, 17% showed intertrochanteric extension on CT scans. Prompt and meticulous search for intertrochanteric extension is mandatory, particularly when CT scan reveals anterior facet involvement.
中文摘要
X光檢顯示孤立大轉子骨折並隱匿性股骨粗隆間擴展
王慧瑜、朱炳容、陳煥章、楊芷蕙、袁銘強
目的：從孤立大轉子骨折患者的X光片上探討隱匿性股骨粗隆間擴展的發生率和骨折形態。
方法：回顧2010年1月至2013年12月期間於香港一所分區醫院的股骨髖部骨折患者的病歷紀錄。孤立大轉子骨折患者列入研究範圍。分析以下資料：人口學數據、病前狀態、CT發現、骨折型態、手術干預、手術結果和隨訪過程中的X光片。
結果：共928例轉子骨折，其中58例（6.3%）的X光片上顯示有孤立大轉子骨折。51例（87.9%）接受CT檢的患者中，10例（17.2%）有股骨粗隆間擴展，當中提供固定手術7例：5例進行動力髖螺釘內固定術，另2例因麻醉高風險而未接受手術。至於CT影像所見的大轉子骨折形態，29例（56.9%）牽涉多於一個小面；大多數牽涉上後小面（39/51，76.5%），其次為前小面（25/51，49.0%）、側小面（15/51，29.4%）和後小面（12/51，23.5%）。有股骨粗隆間擴展的患者中，牽涉前小面的較多（Fisher精確檢驗，p=0.038；比值比=5.65（95%置信區間：1.06-30.0）），牽涉上後小面的則較少（Fisher精確檢驗，p=0.042；比值比=0.21（95%置信區間：0.047-0.91））。兩組之間牽涉後小面和側小面，以及年齡和性別方面均無統計學顯著差異。
結論：X光片上發現有孤立大轉子骨折的患者中，CT顯示17%有股骨粗隆間擴展。當CT掃描顯示牽涉前小面時，需仔細檢查是否有股骨粗隆間擴展。