New techniques have always been emerging in clinical treatment to greatly promote the development of orthopaedics. We must be aware that while we are trying to command the innovations to benefit the patients we should take care to prevent their possible complications. In order to popularize the new techniques actively and safely, we shall first study them carefully. It is necessary that we spare no pains reviewing all the literature concerning them, objectively evaluate their advantages and disadvantages, and have a good command of their indications before we can put them into practice, especially those that have been used abroad. Moreover, we should also develop our skills in practicing the new techniques. We can not only learn from the practice but also make our creative contributions to the improvement of their clinical outcomes in spite of difficulties.

Objective To study hIGF-1 gene expression and the influence on aggrecan expression of degenerative intervertebral disk. Methods Twenty four male New-Zealand rabbits IDD models were established and randomly divided into Ad/CMV-hIGF-1、hIGF-1 growth factor and PBS group. Twenty five mL of Ad/CMV-hIGF-1(T=80?109 PFU/L), hIGF-1 growth factor(100 ?g/L) and PBS were respectively injected into L4-5, L5-6 intervertebral disk through fluoroscopic guidance. One,two,four and eight weeks after-operation, rabbits were sacrificed, intervertebral disk samples were collected. Total protein of equal mass intervertebral disks were extracted, isolated by SDS-PAGE and transferred to polyvinylidene difluoride (PVDF) Millipore. The hIGF-1 growth factor expression were indentified with Western blot. Aggrecan gene fragments were amplified with RT-PCR,and relative expression was checked with GAPDH as intern control. Results The hIGF-1 interest protein existed at 7.6 kilo-Dalton. One week after injection, its expression quantities were almost equal between Ad/CMV-hIGF-1 and hIGF-1 growth factor group. At two week after injection, it obviously declined in hIGF-1 growth factor group. Four week after injection, it was still expressed in Ad/CMV-hIGF-1 group. Eight week after injection, it did not express in three groups. Aggrecan gene relative expression increased significantly from one to four weeks after injection, declined slightly by the end of eight weeks in Ad/CMV-hIGF-1 group. However, it appeared to decrease continuously in the other two groups with time. Conclusion Ad/CMV-hIGF-1 successfully infected degenerative intervertebral disk. The hIGF-1 gene expression lasted four weeks and could stimulate aggrecan synthesis in Ad/CMV-hIGF-1 group.

Objective To study aggrecan, collagen type Ⅰ and collagen type Ⅱ gene expression of intervertebral disk degeneration through destroying bilateral zygapophysial joints of New-Zealand rabbit. Methods Thirty male New-Zealand rabbits were randomly divided into operation groups on the bone and operation group on the soft tissue. In operation group of the bone, L4 and L5 inferior articular processes were en bloc excised, L5 and L6 superior articular processes were retained. In the operation group of soft-tissue, only L3 to L7 paravertebral muscles were stripped. In operation group of the bone, L4-5 and L5-6 intervertebral disks were acted as experimental group; L3-4 and L6-7 acted as self-control group. In the operation of soft tissue, L4-5 and L5-6 were acted as experimentalcontrol group. One、two、four and eight months post-operation, New-Zealand rabbits were killed. Aggrecan, collagen type Ⅰ and collagen type Ⅱ gene expression were performed with semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). Results Aggrecan and collagen type Ⅱ mRNA levels decreased markedly, whereas type Ⅰ collagen mRNA gradually increased. At the same time, aggrecan, collagen type Ⅱ gene expression were the least in experiment group, whereas were most in the experiment-control group. Collagen type Ⅰ showed the contra-tendency. Conclusion Intervertebral disk degeneration can be induced through destroying L4-5 and L5-6 zygapophysial joints of New-Zealand rabbit.Aggrecan, collagen type Ⅰ and collagen type Ⅱ gene expression can reflect intervertebral disk degeneration.

Objective To evaluate the variation of the blood flow in anterolateral femoral head by ligating different amount of extracapsular arteries. Methods Thirty six hips of 18 mongrel puppies were divided into A、 B、 C、 D and E groups. In group A, only one peripheral artery was ligated randomly. In groups B, C, D,and E, 2, 3, 4, and 5 peripheral arteries were respectively ligated. The blood flow in anterolateral femoral head in 18 mongrel puppies was measured before and after the ligation of the arteries by using of Hydrogen clearance technique. Results 1) The average blood flow in anterolateral femoral head was (0.1397?0.0515) ml?min-1?ml-1. 2) The mean blood flow in the anterolateral femoral head was slightly decreased after one to two of the extracapsular main arteries were ligated but there was no statistical difference. However, the mean blood flow was decreased significantly after more than three arteries were ligated. Conclusion 1) Hydrogen clearance technique is a quite simple, economic and reliable method for estimation of blood flow perfusion in various tissue. 2) The efficiency of blood supply of the anterolateral femoral head in puppies depends at least upon three of the major extracapsular arteries.

Objective To introduce the use of artificial lumbar intervertebral disc replacement for the treatment of lumbar disc degenerative diseases and lumbar disc herniation accompanying evident disc space narrowing. Methods Thirty-one cases(37 discs) of artificial lumbar disc replacement were performed using SB Charite Ⅲ from April 1998 to April 2000. Among them, disc degenerative diseases were seen in 16 cases (18 discs), disc herniation accompanying evident disc space narrowing in 13 cases (17 discs), recurrent disc herniation in 2 cases. Results All the cases were followed up from 17 to 41 months(mean, 26 months) . The clinical outcomes were excellent in 23 cases, good in 6 cases, fair in 2 cases. The mobility of the operated level had 4.0? anterior flexion and 5. 1? posterior extension after operation and 9. 1? on total mobility. Meanwhile, the operated intervertebral space got an average of 4. 2 mm higher than that before the surgery. Because of technical problem, a slight displacement of the core occurred in one case without any clinical symptoms and signs. Conclusion Artificial disc replacement is a new operation for the treatment of lumbar disc degenerative diseases and disc herniation accompanying evident disc space narrowing.

Objective To study artificial lumbar intervertebral disc three-dimensional finite element model and its stress state. Methods The three-dimensional finite element models of artificial lumbar intervertebral disc were established by finite element software MSC. MARK. While L4-5 motion segment from young healthy cadaver was created to give the models biomaterial characters. The vertebral disc of L4-5 was replaced by artificial lumbar intervertebral disc to make a model of an artificial disc replacement. Results After three-dimensional finite element models with biomaterial characters of artificial lumbar intervertebral disc and L4-5 motion segment had been created, the stress distribution of artificial lumbar intervertebral disc showed some characteristics as follows:1)The stress exerted in the center of polyethylene slide core and end plates is biggest in all motion states, the next exists at the deviated site while the polyethylene slide core set in motion. 2)The upper surface of polyethylene slide core and end plates bear 2-3 times stress as much as that of the lower surface. 3)The biggest stress exists in the center of polyethylene slide core and end plates during compression in all motion states. Conclusion Establishment of three-dimensional finite element models of artificial lumbar intervertebral disc and analysis of its stress are feasible. The results are reliable.

Objective To investigate the efficacy of percutaneous endoscopic laser-assisted discectomy (PELD) on L5S1 herniated nucleus pulposus by posterior paramedian trans-interlaminar approach (PEILD). Methods 168 consecutive patients underwent PEILD between May 2002 and December 2003, and were analyzed retrospectively. All cases were operated in outpatient department under local anesthesia in Wooridul Spine Hospital of Korea. Of the 168 cases, 92 were males, and 76 females with a mean age of 42.8 years (range,18 to 73 years ). The classification of herniated disc position related to spinal canal and pedicle, was central in 22, para-central in 120, foraminal in 23, and extraforaminal in 3. The average of iliosacral distance was 38.6 mm. "C" arm fluoroscopy was needed during operation. All of the patients were given conservative management for 6 to 8 weeks without relief of radiculalgia. The AP film was used to make sure to have enough working interlaminar space of posterior percutaneous approach for L5S1 herniated nucleus pulposus. Results The operative time was 30 to 90 mins with an average of 45 mins, and the mean hospitalization was 1.3 days. The average follow-up duration was 8.3 months (range, 5 to 19 months), and the patients were evaluated at 2 day, 2 week, and 1, 2, 6 and 12 month respectively. The clinical results were assessed by MacNab criteria, there were excellent in 43.5%, good in 47.0%, fair in 4.8%, and poor in 4.8%, and successful rate was 90.5%. 8 cases showed incomplete removal of the pathological disc on postoperative MRI without changes of symptoms and signs, then open laminectomy and microdiscectomy (OLM) were performed, including 4 of foraminal type, 3 of extraforaminal type and 1 of central type. 1 case displayed discitis, which was improved one month later by intravenous antibiotics, immobilization and bedrest. 26 cases showed transient postoperative paresthesia, improved by conservative treatment. Conclusion L5S1 disc herniation can be effectively treated with percutaneous endoscopic laser discectomy through posterior paramedian trans-interlaminar approach, which is easier for the patients with higher iliac spines.

Objective To introduce a new technique about reconstruction of anterior cruciate ligament(ACL) by transplantation of autogenous hamstring and fixation with a crossbar(Transfix Ⅱ) under arthroscopy and explore its effect on short term. Methods 72 patients with ACL injury were treated with ACL reconstruction by transplantation of autogenous semitendinous and gracilis tendon, fixed by a crossbar in femur end and a bio-absorbable interface screw in tibial tunnel. 2 cases of meniscus neoplasty, 31 partial meniscectomy, 8 large partial meniscectomy, 16 cartilage trimming, and 15 medial collateral ligament neoplasty, as well as 1 patellar tendon neoplasty were performed simultaneously. Pre- and post-operative knee joint function and stability as well as X-ray photograph were evaluated according to the Lysholm scoring scale system. The reliability of the fixation and its short-term effect were analyzed. Results 65 patients were available for follow-up with the duration from 8 to 36 months. The function of knee joint improved greatly. 8 cases had positive finding in physical examination. The average pre- and post-operative Lysholm score were 56?6.3 and 91?4.8, respectively(P

Objective To study a simple?minimally invasive?safe?effective and economical therapy for osteoportic vertebrae compression fracture. Methods 9 patients with 14 vertebrae (13 lumbar, 1 thoracic) suffered from osteoportic compression fractures were treated with percutaneous vertebrolasty from March to September in 2001. The patients included 8 women and 1 man aged from 33 to 85 years with a mean of 72 years. Results All patients had marked to complete pain relief at 1～2 postoperative days, and could get up to move at 2～3 postoperative days. During 1-6 months follow-up period, no pain reoccurred. No severe comlication occurred. Conclusions Percutaneous vertebroplasty provided significant pain relief in the patients with osteoportic vertebrae compression fractures. It is a promising therapy for patients with osteoportic vertebrae compression fracture.

Objective To investigate the clinical effects of surgical treatment of acute deep vein thrombosis (DVT) in the lower limbs. Methods Twenty four cases with DVT were treated with a 2～3cm incision at the cross of superficial and deep femoral veins to take the thrombasis out. Moulding thrombasis were pulled up with ova circular tongs, and fragmented thrombi were spilled out of the incision with the prelum arteriol winding from foot to thigh. The artery was rinsed with heparinized saline for three minuets till the femoral vein was completely unobstructed. The vein was sutured, and the wound was drained under negative pressure. Results The near future effects: Limb swelling and pain disappeared in seventeen cases, conditions turned for the better in six cases, and there was no improvement in one case. The long term effects: Twenty one were followed up for an average of one year and three months. All patients had excellent walking and standing except two cases who suffered lower limb swelling and pain occasionally. Conclusions The operation of vein thrombectomy is a simple, easy and excellent approach to treat DVT, especially within six days after the the condition.