Comparison between pathology and computer for quantitative determination of femoral head necrosis / 中国骨伤

OBJECTIVE@#To compare computer measurement semi automatic quantitative detection software system with ultra thin layer pathological section to confirm the avascular necrosis percentage of the femoral head, and provide reference for clinical treatment options.@*METHODS@#From June 2012 to December 2013, the X-ray and MRI of 24 patients(24 hips on unilateral) were reviewed, who had avascular necrosis of the femoral head at late stage (stage III and IV) according to the ARCO international staging system, and performed by total hip arthroplasty. There were 15 males and 9 females, with an average age of (65.1±8.8) years old ranging 33 to 74 years old. Based on imaging system combined with computer aided technology(CAD) system and postoperative ultrathin slice, the volume of the area of femoral head necrosis were calculated. Then combining with the total volume of the femoral head was calculated by X-ray, the percentage of each femoral head necrosis area was calculated as a percentage of the whole ball head in both methods.@*RESULTS@#For 24 hips, the normal femoral head volume was (39.58±3.29) cm³ on average of X-ray film, the necrotic volume was (20.00±3.04) cm³ on average of MRI by the calculation of computer. The necrotic volume occupying in the volume of the normal femoral head was (42.92±6.09)% on average ranged. The necrotic lesion size was larger than 40% in 16 hips, 30% to 40% in 8 hips, 1 ess than 30% in 0 hip. Under the pathological section, the necrosis volume was (19.89±3.17) cm³, the necrotic volume occupying in the volume of the normal femoral head was (40.33±6.36)%. The necrotic lesion size was larger than 40% in 12 hips, 30% to 40% in 11 hips, 1 ess than 30% in 1 hip. In computer and general measurement, the two entire femoral head volume difference was (0.113±0.466) cm³, there was no significant difference using these measurements(=-1.186, =0.248). After the linear correlation statistics analysis, there was a positive correlation relationship in necrotic volume between computer software and pathology measurement(γ=0.980, =0.000).@*CONCLUSIONS@#The severity of the necrotic femoral head is closely related to the percentage of necrotic area. When the ratio of necrotic lesions and the whole femoral head is greater than 30%, the patients' clinical symptoms tend to aggravate, the probability of total hip arthroplasty increased significantly. It have great significances in femoral head necrosis installment, judge the prognosis, guide the selection of treatment and monitoring curative effect.

Treatment of flexion-distraction thoracolumbar fractures by postural reduction with instrumental reduction / 中国骨伤

<p><b>OBJECTIVE</b>To study the curative effect of postural reduction with instrumental reduction in treatment of flexion-distraction thoracolumbar fractures.</p><p><b>METHODS</b>A retrospective study was performed on 43 patients with single thoracolumbar flexion-distraction fractures admitted from August 2009 to August 2011, included 28 males and 15 females with an average age of 44 years old (34 to 56 years old). All patients were treated with postural reduction with instrumental reduction. The kyphosis (Cobb angle) recovery of injured vertebral height and complication were analyzed. The visual analogue scale(VAS) and com-plications were followed up and recorded.</p><p><b>RESULTS</b>There was no difference in recovery of injured vertebral posterior height among preoperative, 1 week and 1 year after operation (P > 0.05). There were significantly difference in kyphosis (Cobb angle) and recovery of injured vertebral anterior height between preoperative and postoperative at 1 week (P < 0.05). There was no difference in kyphosis (Cobb angle) and recovery of injured vertebral anterior height between 1 week and 1 year after operation (P > 0.05). VAS significantly improved from preoperative (7.2 +/- 1.2) to (0.8 +/- 0.7) at 1 year after operation (t = 18.47, P < 0.001).</p><p><b>CONCLUSION</b>Postural reduction with instrumental reduction is effective for thoracolumbar flexion-distraction fractures and it is beneficial to the recovery of vertebral height and saggital alignment.</p>

Biomechanical study on the posterior screw fixation in the lower cervical spine / 中国骨伤

So far, the fixation in the lower cervical spine through posterior approach technology has commonly been used, besides the lateral screw and pedicle screw techniques, transarticular screw and laminar screw techniques have being paid more attention recently. This article introduced four screw fixation ways in the lower cervical spine through posterior approach and reviewed the recent biomechanics studies of four screw fixation techniques. The biomechanics study includes stabilization, pollout strength, insertion technique, and screw characteristic and so on. Lateral screw and pedicle screw techniques have become an effective internal fixation way for the lower cervical spine instability because of their superior stabilization and higher pollout strength. Transarticular screw fixation has become a new way to fix the lower cervical spine through posterior approach, which has widely surgical indications. Besides, this technique is relatively safe, simple and has achieved favorable curative effect in clinic. Laminar screw fixation technique is rarely used in clinic, but the study of anatomy and biomechanics confirmed that this technique can be applied as a salvage technique in clinic. Above four techniques of the screw fixation in the lower cervical spine through posterior approach have advantages and disadvantages, respectively, and the application in clinic is different. Through the biomechanics study of these techniques will contribute to the development of the techniques of the screw fixation in the lower cervical spine through posterior approach and guide the clinical work effectively.

Case-control studies of the treatment for the distal clavicle fracture by elastic band inclined "8" fixation / 中国骨伤

<p><b>OBJECTIVE</b>To compare the effects of the treatment for the distal clavicle fracture with two different methods.</p><p><b>METHODS</b>There were 120 cases of the distal clavicle fractures involved in the study. Among them, 75 cases were treated by self-improved elastic band inclined "8" fixation (Manipulation group), 45 cases were treated by open reduction and internal fixation with clavicular hook plate (Operation group).</p><p><b>RESULTS</b>There was statistically significant difference between manipulation group (6.71+/-2.35 weeks) and operation group (11.38+/-4.58 weeks) in the time of fracture union (P<0.01); but, there was no statistically significant difference between manipulation group (100%) and operation group (97.8%) in the rate of fracture union (P>0.05). According to the evaluation of shoulder-joint function, 56, 14 and 5 cases obtained excellent, good and bad result respectively in manipulation group; 38, 5 and 2 cases obtained excellent, good and bad respectively in operation group. There was no statistically significant difference between manipulation group (93.3%) and operation group (95.5%) in the rate of excellent and good (P>0.05).</p><p><b>CONCLUSION</b>Compared with open reduction and internal fixation with clavicular hook plate, treatment with self-improved elastic band inclined "8" fixation can shorten the union time of fracture and reduce therapeutic risks, so it is an economical, practical and safe method for the distal clavicle fracture.</p>