Objective To establish a way to measure the injury severity of articular surface due to posterior malleolus fracture and investigate its clinical significance based on three-dimensional reconstruction technique.Methods Between May 2009 and March 2014,138 cases of peri-ankle injury combined with posterior malleolus fracture were treated.Lateral radiographs were reviewed to measure the ratio of posterior fragment area to distal tibial plafond area using the common method.Three-dimensional CT images were examined to measure ratio of the area of injury using the three-dimensional measuring method.Statistical comparison was made using the t-test and intraclass correlation coefficient (ICC).Results Measurement failed on 33 lateral radiographs and 13 three-dimensional CT images.Six cases cannot be measured by both imaging technology,so results of 98 cases were compared.Ratio of posterior fragment area to tibial plafond area was (16.2 ± 7.2) ％ measured by radiographs and was (29.6 ±10.1) ％ by three-dimensional CT scans (P ＜ 0.05).Three-dimensional CT measurements showed higher intra and inter-observer agreement (ICC of 0.973 to 0.942) than that in radiographic measurements (ICC of 0.875 to 0.860).Conclusion Three-dimension CT assessment of the extent of injury to articular surface because of posterior malleolus fracture is reliable and reproducible,but radiographic assessment may underestimate the injury and influence the choice of surgical indications.

Objective To provide references for anatomical reduction and correct implantation in treatment of distal fibular fracture by analyzing morphological characteristics of distal fibula on three-dimensional (3D) modes.Methods 16-row spiral CT scans of 126 normal ankle structures from May 2009 to June 2014 were collected.Surface shaded display technique was used to reconstruct 3-D images of bones around the ankle.The distal fibula was extracted using 3D segmentation technique.The parameters of distal fibula were measured by selecting points,lines and surfaces on the 3D models.Results The morphological characteristics of distal fibula were complicated.Significant differences were observed between males and females in most parameters (P ＜ 0.05),but not in the length between the plane of the most lateral point of the tibial anterior node and the most distal point of the fibula,the length between the midpoint of lateral border of the fibula and its opposite cortex on the plane of the most proximal border of the fibular fossa or the mean angle of posterior crest of the fibula (P ＞ 0.05).The intra and interclass correlation coefficients (ICC) were excellent.Conclusions When a lateral plate is used for internal fixation of distal fibula,the plate should be placed as proximally as possible.When a posterior-lateral plate is used,the screws to be inserted on the plane proximal to the initial point of anterior node of the tibia can be fixed bi-cortically.When a posterior plate is used,pre-contour of the plate before insertion is required.

Objective To discuss the curative effect of computer assisted pre-operation plan (CAPP) in treating the geriatric intertrochanteric femoral fracture.Methods The data of intertrochanteric fractures treated with PFNA-Ⅱ between March 2012 and June 2015 were retrospectively analyzed.They were divided into two groups by preoperative design.One group was the CAPP group consisting of 53 patients with a mean age of 75.3 years (range,60-92 years).According to the Evans Classification,there were 12 Evans type Ⅰb,9 Evans type Ⅰc,15 Evans type Ⅰd and 17 Evans type Ⅱ fractures.The other group was the non-CAPP group consisting of 74 patients with a mean age of 76.6 years (range,62-95 years).There were 18 Evans type Ⅰb,15 Evans type Ⅰc,20 Evans type Ⅰd and 21 Evans type Ⅱ fractures.Operation time,intraoperative blood loss,times of fluoroscopy during operation and days of hospital stay were compared.The hip joint function was evaluated by Harris score at the final follow-up.Results The CAPP meanly cost 24.7 min.The consistency of the surgery and CAPP was up to 100％.In the CAPP group,the average operation time was 46.8±6.5 min;the average times of fluoroscopy during operation were 12.0±2.3 times;and the average blood loss was 154.4±27.6 ml.In the non-CAPP group,the average operation time was 57.8±10.3 min;the average times of fluoroscopy during operation was 20.9±3.2;and the average blood loss was 235.0±65.8 ml.All above data in the CAPP group were significantly lower than those in the non-CAPP group.The mean days of hospital stay were 13.9±1.3 days in the CAPP group and 14.3±1.4 days in non-CAPP group.The days of hospital stay had no significant difference between the two groups.Forty-five patients with an average follow-up period of 18.3 months were reviewed in the CAPP group.Fifty patients were followed up with an average period of 19.2 months in the non-CAPP group.At the final follow-up,the average Harris score was 88.6±2.8 points (range,84-96 points) in the CAPP group and 87.5±3.2 points (range,80-95 points) in the non-CAPP group.Conclusion CAPP system is convenient and efficient.It can facilitate the treatment of intertrochanteric fracture effectively.

Objective To investigate the three-dimensional morphological characteristics of tibial plateau based on CT image post-processing technique and analyze its significance in preoperative planning of tibial plateau fractures.Methods Multi-slice spiral CT data of 98 humans (56 males and 42 females) with normal tibial plateau and 30 patients (15 males and 15 females) with tibial plateau fractures were extracted.Morphological measurements of the tibial plateau were achieved by means of a three-dimensional measurement method based on points,lines and surfaces.Differences in threedimensional parameters between genders in normal tibial plateau and differences between normal tibial plateau and tibial plateau fractures were analyzed.Results Differences of males and females were significant in width of tibial plateau [(73.2 ± 3.7) mm,(65.5 ± 3.7) mm],anteroposterior dimension of medial tibial plateau [(39.8 ± 3.5) mm,(34.8 ± 2.6) mm] and anteroposterior dimension of lateral tibial plateau [(34.0 ± 3.3) mm,(29.8 ± 3 5) mm] (P ＜ 0.05),but not in varus inclination of tibial plateau [(3.19 ± 1.98) °,(3.16 ± 1.89) °],medial plateau posterior slope [(7.31 ± 3.04) °,(8.16 ± 2.46)°] and lateral plateau posterior slope [(5.23 ±2.35)°,(5.60 ±2.55)°] (P ＞0.05).Above parameters in three-dimensional morphological measurements of tibibial plateau fractures varied compared to the normal reference value (P ＜ 0.05).Intraclass correlation coefficient (ICC) for intra-observe and inter-observer agreement in normal tibial plateau measurement was excellent.Conclusions Present research provides a series of scientific and objective data for preoperative planning of tibial plateau fractures.Measurements of tibial plateau can assist the evaluation of reduction of tibial plateau fractures.

Objective: To explore the advantages of endoscopy combined with contrast fistulography in the clinical diagnosis and treatment of chronic wound with sinus tract adjacent to body cavity. Methods: Thirty-two patients (14 males and 18 females, aged 17 to 87 years) of chronic wounds with sinus tracts adjacent to body cavity, who underwent endoscopy combined with contrast fistulography (CT or magnetic resonance imaging) for the diagnosis and treatment in the Outpatient Department of Wound Healing Center of our hospital from October 2017 to March 2019, were enrolled in the study. Their diagnosis and treatment results were retrospectively analyzed. The following data were calculated. (1) The incidence rates of sinus wound involving body cavity or fistula. (2) The detection rates of sinus wound involving body cavity detected by routine examination and by endoscopy combined with contrast fistulography. (3) The detection rate of pathological features at deep part of wound by routine examination and by endoscopy combined with contrast fistulography. (4) The proportion of patients who benefited from routine examination and from endoscopy combined with contrast fistulography. Data were processed with paired chi-square test and Fisher′s exact probability test. Results: (1) The incidence rate of sinus wound involving body cavity was 43.75% (14/32); the incidence rate of fistula was 0. (2) The detection rate of sinus wound involving body cavity detected by endoscopy combined with contrast fistulography was 43.75% (14/32), which was obviously higher than that by routine examination [12.50% (4/32), χ²=32.0, P<0.01]. (3) The detection rate of pathological features at deep part of wound by endoscopy combined with contrast fistulography was 37.50% (12/32), which was obviously higher than that by routine examination (0, P<0.01). (4) The proportion of patients who benefited from endoscopy combined with contrast fistulography was 71.43% (20/28), which was obviously higher than that from routine examination [12.50% (4/32), χ²=21.6, P<0.01]. Conclusions Compared with routine examination, endoscopy combined with contrast fistulography is more accurate in detecting chronic wound with sinus tract adjacent to body cavity. The diagnosis and treatment of chronic wound with sinus tract adjacent to the body cavity can benefit from this joint examination.