Objective To explore three dimensional relationships of commonly used bony marks of the distal femur, and to investigate its clinical application of distal femur rotational alignment. Methods One hundred and fifteen normal distal femurs of 62 volunteers were studied. With MR sagittal imaging and three dimensional reconstruction, correlative parameters, including PCA (posterior condylar angle), angle between surgical transepicondylar axis (STEA) and posterior condylar line (PCL); CTA(condylar twist angle), angle between clinical transepicondylar axis (CTEA) and PCL; APA, angle between the perpendicular of antero-posterior line (APL) and PCL; ATA, angle between the perpendicular lines of APL and STEA; CSA, angle between CTEA and STEA. All these angles were measured. The parameters of the two groups both in males and females, as well as in right and left knees were analysed. Results PCA: 3.44??1.08? (range, 0.62? to 6.75?); CTA: 6.03??0.86? (range, 2.93? to 8.92?); APA: 4.31??0.64? (range, 1.92? to 7.05?); ATA: 0.87??0.78? (range, -1.72? to 3.84?); CSA: 2.58??0.57? (range, 0.22? to 4.51?). There was no significant difference between left and right knee in terms of all the above mentioned parameters, yet there was significant difference between male and female groups in terms of PCA, CTA and ATA. PCA and CTA were larger in male groups than that of female group, while ATA in female group was larger than that of male group. Conclusion Three dimensional reconstruction based on imagings of MR is a reliable method to study the distal femur rotational alignment. In the normal knees, there is constant relationship between these parameters. Operators should use distal femur rotational alignment according to practical conditions in performing the total knee arthroplasty.

Objective To analyze and evaluate the effect of the elbow posterior dislocation with radial head and coronoid fractures (the terrible triad of the elbow). Methods Nine patients of the terrible triad of the elbow were treated from January 2004 to March 2009. Among of them, according to Schatzker-Tile classification, the radial head fractures were 4 in type I , 3 in type II , 2 in type Ⅲ. According to Rogan-Morrey classification, the ulnar coronoid fractures were 2 in type I , 5 in type II , 2 in type Ⅲ. The general approach was to repair the damaged structures sequentially from deep to superficial, from coronoid to anterior capsule to radial head to lateral ligament complex to common extensor origin. If there was valgus instability in the elbow after the operation, repaired medial ligament with nonabsorption suture. Plaster was applied for 7-10 days,in position of with elbow flexion in 90° and the forearm in full pronation. Unrestricted morion was then begun, and strengthening was initiated at 8 weeks. Returned to regular occupation depended on the degree of physical activity required, and it typically taken 3 months for heavy physical laborers to return to work. , Results All patients were followed up for 6-60 (31 ± 6) months. Three months postoperatively, the flexion-extension arc of the elbow was 80° -110° (102° ± 3° ), and the pronation-supination arc of the forearm was 100° -150° (135° ±6°) respectively. According to the criteria of the Mayo score, the results were excellent in 5 cases, good in 3 cases, and fair in 1 case. Three cases were heterotopic ossification 6 months postoperatively, 2 cases of them didn't impact the elbow function, didn't treat, 1 case impact the flexion-extension of the elbow, cut the heterotopic ossification from the lateral approach, Mayo score improved from fair to good. Conclusion The key points for treating the terrible triad of the elbow are recovering the elbow normal anatomy and starting early functional exercises in order to avoid the elbow stiff.