Objective To investigate the histological changes and collagen phenotype of a semitendinosus autograft after reconstruction of posterior cruciate ligament(PCL) in rabbits. Methods Twenty skeletally mature New Zealand white rabbits were divided into two groups. In group 1, the PCL of the right knees of 18 mature New Zealand white rabbits were resected and immediaterly reconstructed with double-band semitendinosus antograft. Then the rabbits were respectively killed at 3, 6, 12, 26 and 52 weeks after the operation, to obtain the the semitendinosus autografts. Group 2 consisting of the other 2 rabbits was served as control group, and semitendinosus tendons and PCL were obtained. All specimens were staining with hematoxylin and eosin, toluidine blue and immunohistochemical methods of type Ⅰ, Ⅲ collagens to analyze the histological changes and collagen phenotype of a semitendinosus autograft, and compare those with normal semitendinosus tendons and PCL. Results Histological results demonstrated that there was obvious difference at the cell formation between normal semitendinosus tendon and PCL. After postoperative 52 weeks the graft was similar to the normal PCL, while the alignment of graft was still different from that of normal PCL through necrosis, cell growing in, collagen formation and remolding. Immunohistochemistry result demonstrated: the staining of type Ⅰ collagen in graft was low at first, then increased gradually; the staining of type Ⅲ collagen was low at first, increased quickly, then decreased, at 52 weeks it was present in local areas. But positive reactions for type Ⅰ collagen were localized in collagen fibers, and those for type Ⅲ collagen were localized in synovium in normal PCL. Conclusion The study showed the semitendinosus autograft was still different in cell formation from normal PCL at 52 weeks after PCL reconstruction with semitendinosus.

Objective To provide data on the incidence,shape,and sizes of the femoral attach.ments of meniseofemoral ligaments (MFLs),and to determine the function of MFIJs and the role in the femoral tunnel D0sitioning in the double-bundle reconstruction of PCL.Methods Anatomical study:Thirty cadaveric knees were used to investigate the incidence and tightening-slackening patterns during the knee nexion-extension of MFLs.Data were obtained to describe the size,shape,and the relationship between the position of the femoral attachment of MFLs and that of anterolateral bundle(ALB)and the posteromedial bundle(PMB) were detetrained.Clinical study:During arthroscopic reconstruction of PCL,the presence of MFIJs Was confirmed in 1 12 patients by observation and probing,the relationship between the femoral attachment of MFLs and that of ALB and PMB were determined.Results Anatomical study:The Humphry ligament and Wrisberg ligament were presented in l(3%)and 27(90%)case respectively.The femoral attachments were approximately ellipse both.The mean area was(18.14±3.05)mm2 and(25.63±7.92)mm2 respectively.Clinical study:The Humphry ligament and Wrisberg ligament were present in 2 cases(1.7%)and 67 cases(59.8%) respectively.The incidence of MFLs in knees with isolated PCL injury was highter than that in knees with multiple ligaments injuries.Conclusion The incident of MFLs is related to the trauma of the knee.and the Wrisberg ligament plays an important role in avoiding impingement between the ALB and the intereondylar roof during deep knee flexion.The Humphry ligament and the Wrisberg ligament are landmarks for the tunnel positioning of ALB and PMB in double-bundle PCL reconstruction respectively.

Objective To study the influence of the rupture of anterior cruciate ligament(ACL) on the menisci. Methods Four hundred and nineteen consecutive patients with rupture of ACL during December 1984 to December 1999 were included in this study. The incidence of meniscal injuries and the correlation of injuries of menisci and cartilage were investigated. Results The incidence of meniscal injuries was increased from 55.6% in acute to 74.1% in sub chronic and 89.8% in chronic. There were significant differences between each two stages (P

Objective To determine the biomechanical properties of anterior cruciate ligament allograft reconstructing posterior cruciate ligament in rabbits. Methods Based on the study of anatomy and biomechanics of normal rabbit cruciate ligaments, anterior cruciate ligament allografts were employed to reconstruct the posterior cruciate ligament in rabbits. The sterilized fresh-frozen allograft of bone-anterior cruciate ligament-bone were prepared and reserved for more than 14 days under -80 ℃. Twenty-four skeletally matured New Zealand white rabbits underwent a posterior cruciate ligament reconstruction on one knee randomly, the opposite knee was served as the paired control. Rabbits were sacrificed at 6, 12, 26 and 52 weeks respectively. Evaluations of the reconstructions and contralateral controls included the geometric, structural and material properties and rupture site. Results The mean length of the grafts at 52 weeks was 101% of the control (P=0.90), the cross-sectional area was 142%; the maximum load at 52 weeks was 83% of the control, the maximum elongation was 72%, the stiffness was 92%; the maximum stress at 52 weeks was 58% of the control, the maximum strain was 72%, and the modulds was 65%; the rupture site was all at the body part of the graft. The geometric, structural and material properties of the graft were gradually similar to those of the normal posterior cruciate ligament with the elapse of the time. Conclusion The biomechanical properpies of graft with similar material properties to normal posterior cruciate ligament following posterior cruciate ligament reconstruction in rabbits was favourable. The similar material properties of graft to normal posterior cruciate ligament play the very important roles in the posterior cruciate ligament reconstruction.

Objective To observe the articular cartilage injuries complicated with the rupture of anterior cruciate ligament(ACL)in 21 athletes and 43 non-athletes,and investigate the cause and the pattern of cartilage of knee following the ACL rupture in those patients.Methods The pathologic change,location,degree of cartilage lesion were observed. The relationship between the incidence, occurrent time,degree of cartilage injury and ACL rupture,injured degree of cartilage and the course of ACL rupture were studied.Results The incidence of cartilage injury were 75% in all patients, 66.7% in athletes and 79%in non-athletes. Incidence of cartilage injury in non-athletes was significantly higher than that in athletes (P<0.01).Incidence of serious injury of cartilage in the course more than 1 year was significantly higher than that less than 1 year (P<0.01),but there were no statistical difference between the two groups.Conclusion The incidence of articular cartilage injury following ACL rupture were significantly raised in athletes and non-athletes. The longer the ACL ruptured, the more serious the cartilage injured. Results indicated that articular cartilage injuries in the ACL rupture knee were mainly caused by the instability of knee.

Objective To report the diagnostic and therapeutic effects of arthroscopic surgery on elbow sports injuries. Methods Nineteen patients with elbow diseases were treated by arthroscopic methods from January 1996 to February 2000. The modified HSS elbow rating scale was used as criteria of the efficacy. All patients were followed up for 4.5 months to 4.5 years (an average 8.6 months). Results Among nineteen patients, eleven had an excellent results, seven good, one poor, and satisfactory rate was 94.7 percent. Ten patients were satisfied greatly with the results,eight patients satisfied, one unsatisfied, the satisfactory rate was up to 94.7 percent according to the responses of questionnaire from the patients. The time resuming daily was in a medium of 7 days, and that for sports was in an average of 2.5 months. All the 11 cases of athletes and actors(actresses) resumed their previous seats. Complications occurred in 3 earlier cases, one had radial nerve temporary paralysis, the other two had residue loose bodies. Conclusion Elbow arthroscopic treatment is a reliable method with the advantages of minor trauma, quicker recovery and less traumatic manipulation. Careful pre-operative examination, selection of a safer portal of entry, and standard manipulation are very important points for the attainment of better results and less complications.

Objective To study the reasons, patterns of the injury and methods of early reconstruction of the articular cartilage injuries associated with the rupture of anterior cruciate ligament(ACL). Methods The pathologic change, location, degree of articular cartilage lesion were observed in 64 old ACL ruptures and 23 fresh ones by arthroscopy. The relationship between the incidence， duration of the injury, degree of cartilage injury and ACL ruptures, the correlation between the cartilage injury of femoral condyles and meniscus injury were studied. Results The incidence of articular cartilage injury in old ACL rupture group(75％ ) was significantly higher than that in fresh group(26％ )(P

Objective To research for a new method of arthroscopic total meniscectomy with simple instru- ments. Methods One hundred and sixty nine cases were followed up for short period that had been operated on with a forward knife, a back cutting knife, a punch and a 30?scope from Nov. 1992. to Aug. 1998. Results The av- erage time of operation was 78 minutes. The operations had no injury to cartilage and ligament. It is necessary for only 7 .9 percent of patients to take analgesic intramuscularly after operation. Eight patients had a transient tourniquet paral- ysis. All of them could begin to work and exercise after postoperative 2 weeks. Conclusion As compared with the method introduced by David Sisk ,this method has the advantages of simple instruments, fewer ports and complications and minimal trauma Either lateral meniscus or medial meniscus can be cut off by the same method. This method is a safety and a better way to arthroscopic meniscectomy.

In oder to make the bone tunnel in optimal position, effective and firm fixation, early functional recov- ery and minimally operative injury we reported a new technique in reconstructive anterior cruciate ligament(ACL)using patellar tendon autograft fixed with interference screw. With the assistance of arthroscopy 74 patients with ACL rupture were treated between October 1997 and April 1999. The clinical results showed that the operative injury was minimal, fixed bone grafts were accurate and the reconstructed ACL was isometricity. The reconstructed ligament could be fixed biologically and firmly because of used patellor tendon autograft with bone grafts at two end. Clinical experience of ar- throscopic - assisted ACL reconstruction was summarized.

Objective To explore the diagnostic and therapeutic value of arthroscopy for ankle joint sports injury. Methods 52 patients (53 ankles) with ankle sports injury treated by arthroscopy were reviewed retrospectively from December 1992 to December 2001. The modified McGuire Scorting for ankle (1988) was used as efficacy criteria. Results The mean recovery time of daily activities and special sports for the athletes was 10 days and 2.5 months respectively. All of the athletes returned to their previous optimal athletic level except that 1 case recovered slowly due to reinjury. Complications occurred in 3 cases (5 8%). The preoperative score was (60 4?9 1) points and postoperative score (89 0?5 7) points ( t =24 1, P