Dragan Savic

Operative treatment of avulsion fractures of the anterior inferior iliac spine: a two-case report

Avulsion fractures of the anterior inferior iliac spine (AIIS) are rare injuries of the pelvic ring. In two male athletes this injury was missed during initial examination and therefore was not treated optimally. Six months after the initial injury, the patients felt constant pain, and there was a lump in the thigh region; they both also had limited range of hip motion.Therefore, radiography and magnetic resonance imaging of the hip were performed. Avulsion fracture of AIIS was diagnosed and treated surgically with excision of the avulsed fragment. Two years later, both athletes have completely recovered and returned to their usual sporting activities. Isokinetic muscle testing disclosed that the extensor muscles of the operated side of the knee were weaker than those on the uninjured side.

Geometric considerations regarding the surface of the tibial insertion of the ACL graft

We have read the article ‘‘The concept of complete footprint restoration with guidelines for single bundle (SB) and double bundle (DB) ACL reconstruction’’ by Siebold [2] with great interest. We would like to comment the authors on their work. The ultimate goal of anatomic reconstruction surgery is to restore the native anatomy, creation of a tibial tunnel aperture that is similar in size and orientation to the native anterior cruciate ligament insertion. The tibial insertion site ACL is the broadest part of the ligament, and according to Siebold et al. [3], the surface of the tibial insertion site is 114 ± 36 mm. Although 77.8% of specimens had elliptical and 22.2% triangularly shaped tibial insertions [4], the tibial graft position in SB and DB ACL reconstruction usually shows as a circle that does not give an accurate picture of the position of the graft sites on their insertion. In real situations, they appear as irregular surfaces that are for easier visibility considered as an ellipse. The size and position of the ellipse surface of the drilled tibial tunnel affects the drill-bit diameter, sagittal or drillguide angle (angle at which the tunnel intersects the tibial plateau) and transverse angle (tibial drill-guide adjustment by rotating the guide around the tibial shaft). Depending on the drill-bit diameter and the angle of drilling, the surface of the ellipse is changed for the anatomical coverage of the original ACL insertion [1]. If the sagittal angle of the drilled tibial tunnel is lesser, the surface of the tibial insertion is larger and closer to its anatomic shape; if transverse angle is lesser, the anatomical coverage of the original ACL insertion is larger. An optimal combination of these parameters should be selected during the anatomic reconstruction of the anterior cruciate ligament, because if the angle of penetration is lesser, the tibial tunnel is shorter resulting in a disproportion between the graft length and tunnel length, particularly in the BTB techniques. If we consider the geometry, there is no difference in surface of the reconstructed tibial footprint with the most frequently used SB diameter drill-bit 10 mm, and DB diameter drill-bit 6 and 8 mm (Table 1). On the basis of such geometric considerations regarding the surface of the tibial insertion of the graft, we believe that there is no difference in size of the surface of the reconstructed tibial footprint between the SB and DB techniques. During anterior cruciate ligament reconstruction, the drill-bit diameter, sagittal and transverse drill angle affect the size

Behavior of Linear Ligament Biostructure under Action of Different External Forces of Constant Intensity

The behavior of linear ligament biostructure, lig.collareale fibulare, was analyzed. It was shown that particular solution of fundamental equation corresponding to forced vibrations is linearly proportional to coordinate. The elongation of eigen vibrations of this linear ligament, is periodical in time and quasi periodical in coordinate.

Reducing Intra-articular Hemarthrosis After Arthroscopic ACL Reconstruction: Letter to the Editor

Dear Editor: We read with great interest the article by Karaaslan et al titled ‘‘Reducing Intra-articular Hemarthrosis After Arthroscopic Anterior Cruciate Ligament Reconstruction by the Administration of Intravenous Tranexamic Acid.’’ We congratulate the authors on this very interesting study, which provides relevant information on the subject matter. We have, however noticed some ambiguities in the paper:

Anterior cruciate ligament reconstruction with bone-hamstring-bone hybrid procedure

Dear Editors,We read the article ‘‘Augmentation of autologous ham-string graft during anterior cruciate ligament reconstructionusing the bone chip technique’’ by Nha et al. [3] with greatinterest. We would like to commend the authors on theirwork.ACL reconstruction with bone-hamstring-bone (BHB) isa hybrid procedure that lacks the disadvantages of thebone-patellar tendon-bone and semitendinosus and gracilistendon methods while retaining the advantages of thesemethods. Nha et al. [3] described very interesting techniqueto augment the thickness of the hamstring tendon graftduring ACL reconstruction using cancellous bone chipsfrom the femoral intercondylar notch. But this technique isnot new, it should be noted that this technique was pub-lished several years ago. Liu et al. [1] in 1995 measured theinitial fixation strength of a new graft, bone-hamstring-bone (BHB), for reconstruction of the anterior cruciateligament (ACL) in 79 porcine knees and compared it withthat of the normal porcine ACL and of the bone-patellartendon-bone (BPB) graft. Takeuchi et al. [4] in 2002described composite graft prepared by folding the gracilisand the semitendinosus tendons twice and flanking the endsby bone blocks obtained from the tibia. Milankov et al. [2]in 2007 use two cancellous bone cylinders, were taken outof the tibial tunnel, by use of a cancellous bone extractor,and fixed to both ends of the graft by use of sutures. Oneend of the graft was put into a pressing device to achieve agraft diameter of 9 or 10 mm, and then the other end waspressed. By doing so, very strong end parts of the graftwere obtained.We also believe, when using the AM portal techniquefor creation femoral tunnel, it is rarely needed to makenotchplastic, so the usage of bone from that place is notnecessary because it leads to additional damage. It is betterto use cancellous bone cylinders taken out of the tibialtunnel.References