Best bone of acetabulum for cup component placement in Crowe types I to III dysplastic hips: a computer simulation study / 中华医学杂志(英文版)

BACKGROUND@#During cup implantation, vertical height of the cup center (V-HCC) should be precisely controlled to achieve sufficient bone-cup coverage (BCC). Our study aimed to investigate the acetabular bone stock and the quantitative relationship between V-HCC and BCC in Crowe types I to III hips.@*METHODS@#From November 2013 to March 2016, pelvic models of 51 patients (61 hips) with hip dysplasia were retrospectively reconstructed using a computer software. Acetabular height and doom thickness were measured on the mid-acetabular coronal cross section. V-HCC was defined as the vertical distance of cup rotational center to the interteardrop line (ITL). In the cup implantation simulation, the cup was placed at the initial preset position, with a V-HCC of 15 mm, and moved proximally by 3-mm increments. At each level, the BCC was automatically calculated by computer. Analysis of variance and Kruskal-Wallis test were used to compare the differences between groups.@*RESULTS@#There were no significant between-group differences in maximum thickness of the acetabular doom; however, peak bone stock values were obtained at heights of 41.63 ± 5.14 mm (Crowe type I), 47.58 ± 4.10 mm (Crowe type II), and 55.78 ± 3.64 mm (Crowe type III) above the ITL. At 15 mm of V-HCC, median BCC was 78% (75-83%) (Crowe type I), 74% (66-71%) (Crowe type II), and 61% (57-68%) (Crowe type III). To achieve 80% of the BCC, the median V-HCC was 16.27 (15.00-16.93) mm, 18.19 (15.01-21.53) mm, and 24.13 (21.02-28.70) mm for Crowe types I, II, and III hips, respectively.@*CONCLUSION@#During acetabular reconstruction, slightly superior placement with V-HCC <25 mm retained sufficient bone coverage in Crowe I to III hips.

Radiographic Measurement of Femoral Lateral Bowing and Distal Femoral Condyle Resection Thickness: Variances and Effects on Total Knee Arthroplasty Planning / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Accurate evaluation of the plain radiography of lower limb is critical for preoperative planning of total knee arthroplasty (TKA). We aimed to investigate the effect of femoral lateral bowing and rotation on the radiographic measurements of distal femoral condyle resection thickness (DRT) and the distal femoral resection valgus angle (FVA).</p><p><b>METHODS</b>We analyzed 246 three-dimensional femoral models generated from computed tomography images of 123 patients, acquiring projected contours in seven positions - 20° and 10° internal rotation; 0° rotation; 10°, 20°, 30°, and 40° external rotation - for each model. Medial and lateral condyle DRTs, femoral shaft lateral bowing angle (FBA), and distal FVA were determined for each position. Linear mixed effect model was used to determine the effect of degree of femur rotation on repeated measurements of DRT or FVA.</p><p><b>RESULTS</b>FBA significantly affected the FVA and DRT (Pearson's R = 0.767 and -0.408, respectively; P < 0.000). Samples were divided into three groups according to the FBA measured in neutral position: FBA <0°: DRT 3.75 ± 1.30 mm, FVA 4.53° ± 1.27°; FBA >0° but <3°: DRT 3.39 ± 1.31 mm, FVA 5.92° ± 1.31°; FBA >3°: DRT 2.22 ± 1.31 mm, FVA 7.37° ± 1.31°. From simulated 20° internal rotation to 40° external rotation in each femoral model, the average variation ranges of radiographically measured DRT, FVA, and FBA were 0.50 ± 0.28 mm, 2.93° ± 0.96°, and 10.33° ± 1.90°, respectively, with no significant differences among the FBA groups. The degree of femoral rotation significantly affected the FVA (F = 62.148, P < 0.000), whereas there was no effect on condyle resection thickness (F = 0.4705, P = 0.494).</p><p><b>CONCLUSIONS</b>Axial femoral rotation has less effect on radiographic measurements of differences in the DRT than on those of the distal FVA.</p>

Preoperative Measurement of Tibial Resection in Total Knee Arthroplasty Improves Accuracy of Postoperative Limb Alignment Restoration / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Accuracy of implant placement in total knee arthroplasty (TKA) is crucial. Traditional extramedullary alignment instruments are fairly effective for achieving the desired mean tibial component coronal alignment. We modified the traditional tibial plateau resection technique and evaluated its effect on alignment restoration.</p><p><b>METHODS</b>Two hundred and eighty-two primary TKAs in our hospital between January 2013 and December 2014 were enrolled in this retrospective study. Group A consisted of 128 primary TKAs performed by one senior surgeon. Preoperative measurement of the tibial resection was conducted on radiographs, and the measured thicknesses of the lateral and medial plateau resection were used to place the tibial alignment guide. Group B consisted of 154 primary TKAs performed by the other senior surgeon, using a traditional tibial plateau resection technique. In all patients, an extramedullary guide was used for tibial resection, and preoperative and postoperative full-leg standing radiographs were used to assess the hip-knee-ankle angle (HKA), femoral component alignment angle (FA), and tibial component alignment angle (TA). A deviation ≥3° was considered unsatisfactory. Data were analyzed by unpaired Student's t-test.</p><p><b>RESULTS</b>The mean postoperative HKA and TA angles were significantly different between Groups A and B (178.2 ± 3.2° vs. 177.0 ± 3.0°, t = 2.54, P = 0.01; 89.3 ± 1.8° vs. 88.3 ± 2.0°, t = 3.75, P = 0.00, respectively). The mean postoperative FA was 88.9 ± 2.5° in Group A and 88.9 ± 2.6° in Group B, and no significant difference was detected (t = 0.10, P = 0.92). There were 90 (70.3%) limbs with restoration of the mechanical axis to within 3° of neutral alignment and 38 (29.7%) outliers (>3° deviation) in Group A, whereas there were 89 (57.8%) limbs with restoration of the mechanical axis to within 3° of neutral alignment and 65 (42.2%) outliers (>3° deviation) in Group B. The severity of the preoperative alignment deformity was a strong predictor for postoperative alignment.</p><p><b>CONCLUSIONS</b>Using conventional surgical instruments, preoperative measurement of resection thickness of the tibial plateau on radiographs could improve the accuracy of conventional surgical techniques.</p>

Ceramic-on-ceramic versus ceramic-on-polyethylene bearing surfaces in total hip arthroplasty：a meta analysis of efficacy and safety / 中国组织工程研究

BACKGROUND: Greatly importance has been attached to ceramic-on-ceramic bearing surface due to its excel ent wear resistance. But the risks of squeaking and ceramic fracture also go with it. Up til now, the choice between ceramic-on-ceramic and ceramic-on-polyethylene bearing surfaces in primary total hip arthroplasty remains controversial. OBJECTIVE: To compare the clinical outcomes and safety between ceramic-on-ceramic versus ceramic-on-polyethylene bearing surfaces in total hip arthroplasty based on meta analysis. METHODS: We electronical y searched databases including PubMed/Medline, Embase, Web of Science, Cochrane Col aboration database, Chinese Biomedical Literature Database (CBMdisc) and China National Knowledge Internet for randomized control ed trials on the comparison between ceramic-on-ceramic versus ceramic-on-polyethylene bearing surfaces in total hip arthroplasty from inception to January 2015. References of the included studies were also retrieved. Investigators severely selected the studies, extracted data and assessed the quality according to the inclusion and exclusion criteria. Then, meta-analysis was performed using RevMan 5.2 software. RESULTS AND CONCLUSION: Nine randomized control ed trials were included, involving 1 231 hips with ceramic-on-ceramic prosthesis and 932 hips with ceramic-on-polyethylene prosthesis. Meta analysis showed that both bearing surfaces achieved satisfied function recovery. But ceramic-on-ceramic had significantly increased risks of squeaking and ceramic fracture, meanwhile ceramic-on-polyethylene showed significantly higher wear rate. There were no significant differences in intra- or post-operative dislocation, osteolysis and other complications and prosthesis failure with any reason between two bearing surfaces. These results suggest that during the short- to mid-term fol ow-up period, no sufficient evidence can tel that ceramic-on-ceramic was obviously super than ceramic-on-polyethylene. Long-term fol ow-up is required for further evaluation.

Comparison of the prognosis of intertrochanteric fracture with different surgical methods in elderly: a retrospective survival analysis / 中国骨伤

<p><b>OBJECTIVE</b>To determine the difference of post-operative mortality between ORIF (open reduction internal fixation) and hip replacement for the treatment of intertrochanteric fracture in elderly by using survival analysis.</p><p><b>METHODS</b>The clinical data of 110 patients above 60 years old who underwent surgical treatment (ORIF or hip replacement) for the intertrochanteric fracture between April 2003 and May 2013 were retrospectively analyzed. Among the patients, 83 cases were treated with ORIF (ORIF group), there were 32 males and 51 females, aged from 61.44 to 98.75 years old with an average of (78.52 ± 7.98) years old; and 27 cases were treated with hip replacement (arthroplasty group), there were 8 males and 19 females, aged from 71.82 to 96.54 years old with an average of (79.99 ± 6.11) years old. A survival analysis was performed on the clinical data by using SPSS 110 software. The survival rate of 1-year,2-year, 5-year and the mean survival time for the total patients, the mortality rate of 1-year, 2-year in each group, the survival rate of 1-year, 2-year and mean survival time and survival curve in each group were included.</p><p><b>RESULTS</b>All wounds achieved primary healing and no deaths were found in stay hospital. All patients were followed up from 1 to 125 months with an average of (46.93 ± 29.53) months. Among all 110 cases, 31 were dead and 79 survived. The survival rate of 1-year, 2-year and 5-year was (90.7 ± 2.8)%, (82.5 ± 3.9)% and (57.6 ± 6.5)%, respectively,while the ensemble mean survival time was (84.137 ± 5.902) months. The mortality rate of 1-year, 2-year in ORIF group was 7.2% and 12.0%, respectively; and in arthroplasty group, there was 14.8% and 25.9%, respectively. There was no significant difference in mortality rate of 1-year and 2-year between two groups. According to the survival analysis of the ORIF group, the survival rate of 1-year, 2-year was (92.6 ± 2.9)%, and (85.8 ± 4.3)%, respectively, and the mean survival time was (87.508 ± 6.063) months. In arthroplasty group, the survival rate of 1-year, 2-year was (85.2 ± 6.8)% and (73.9 ± 8.5)%,and the mean survival time was (67.294 ± 11.180) months. There was significant difference in mean survival time between two groups (P < 0.05).</p><p><b>CONCLUSION</b>ORIF can achieve a better postoperative survival compare with hip replacement in treating intertrochanteric fracture in elderly.</p>

Autologous nucleus pulposus transplantation to lumbar 5 dorsal root ganglion after epineurium dissection in rats: a modified model of non-compressive lumbar herniated intervertebral disc / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Nucleus pulposus of intervertebral discs has proinflammatory characteristics that play a key role in neuropathic pain in lumbar herniated intervertebral disc. One of the most commonly used animal models (the traditional model) of non-compressive lumbar herniated intervertebral disc is created by L4-L5 hemilaminectomy and the application of autologous nucleus pulposus to cover the left L4 and L5 nerve roots in rats. However, such procedures have the disadvantages of excessive trauma and low success rate. We proposed a modified model of non-compressive lumbar herniated intervertebral disc in which only the left L5 dorsal root ganglion is exposed and transplanted with autologous nucleus pulposus following incision of epineurium. We aimed to compare the modified model with the traditional one with regard to trauma and success rate.</p><p><b>METHODS</b>Thirty Sprague-Dawley male rats were randomized into three groups: sham operation group (n = 6), traditional group (n = 12), and modified group (n = 12). The amount of blood loss and operative time for each group were analyzed. The paw withdrawal threshold of the left hind limb to mechanical stimuli and paw withdrawal latency to heat stimuli were examined from the day before surgery to day 35 after surgery.</p><p><b>RESULTS</b>Compared with the traditional group, the modified group had shorter operative time, smaller amount of blood loss, and higher success rate (91.7% versus 58.3%, P < 0.05). There was no decrease in paw withdrawal latency in any group. The sham operation group had no decrease in postoperative paw withdrawal threshold, whereas the modified and traditional groups had significant reduction in paw withdrawal threshold after surgery (mechanical hyperalgesia).</p><p><b>CONCLUSIONS</b>Transplantation of nucleus pulposus onto the L5 dorsal root ganglion following incision of epineurium in rats established an improved animal model of non-compressive lumbar herniated intervertebral disc with less trauma and more stable pain ethology.</p>

Clinical analysis of revision after primary hip replacement in the early stage / 中华外科杂志

<p><b>OBJECTIVES</b>To analyze the reason of revisions no more than 5 years after primary hip replacement, and to discuss the methods how to prevent and manage.</p><p><b>METHODS</b>Retrospectively review 11 cases with revision no more than 5 years after primary total hip replacement from January 2002 to June 2007. The reasons for revision were as follows: 2 cases were recurrent dislocation due to malposition of acetabular prosthesis; 5 cases were loosening of acetabular prosthesis; 1 case was abrasion of the native acetabulum by bipolar femoral head; 2 cases were periprosthetic femoral fractures and 1 case was periprosthetic infection. The average follow-up time was 36 months. Each patient was assessed according to Harris hip score. The revision procedures including liner only, acetabular prosthesis only, or both acetabular prosthesis and femoral prosthesis depending on the reasons for revision, two-stage revision was performed on 1 case with periprosthetic infection.</p><p><b>RESULTS</b>The average of Harris hip score was increased from 46 (28 to 62) preoperatively to 86 (75 to 96) at follow up. The complication occurred in 2 cases: one was postoperative haematoma formation who was performed further surgery for clearance of haematoma, another was slight instability of the hip joint who was accepted skin traction for 3 weeks.</p><p><b>CONCLUSIONS</b>The main reason for revision after primary total hip replacement is related to uncorrected insert of acetabular prosthesis. Improving surgical technique of insert of acetabular prosthesis is important in primary total hip replacement.</p>

Study on effect of sho-saiko-to compound on growth of nasopharyngeal carcinoma cells in CNE-bearing nude mice / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the role of sho-saiko-to compound (SSTC) on the growth of the well-differentiated squamous cell line 1 of nasopharyngeal carcinoma (CNE-1) and well-differentiated CNE-2 in tumor-bearing nude mouse, and try to supply scientific data for its clinical development.</p><p><b>METHOD</b>SSTC were prepared by concentration gradients, and the effect of SSTC on the growth and proliferation of the CNE-1 and CNE-2 were investigated by MT assay and soft-agar colony formation test. After setting up the subcutaneous tumor-bearing nude mouse model at the right lower back (0.2 mL CNE-2 cell suspension, 5 x 10(5)/mL), we randomly divided forty mice into 5 groups and gave high, middle and low concentration groups of SSTC (0.5, 0.25, 0.125 g X mL(-1) by intragastric administration. Positive and negative groups were set up for comparison. After constant administration for 15 days, the volume and weight of the tumor were measured for inhibition rate, so as to investigate the role of SSTC on the CNE-2 bearing tumor.</p><p><b>RESULT</b>In vitro, compared with negative control, SSTC at different gradient concentrations were cultured with the CNE-1 and CNE-2 for 24 h, 48 h and 72 h. It showed that the growth and proliferation of both cell lines were inhibited to some extent. The inhibition rate was increased as the concentration and culture time increasing. Both MTT assay and soft-agar colony formation test showed that the 50% inhibiting concentration (IC50) was about 2.5 g X L(-1). In vivo, compared with negative control, the SSTC could slow down the tumor growth in the SSTC treated groups. The tumor growth of the negative control group (0.76 +/- 0.28) g, (962.88 +/- 245.96) mm3 and the low concentration group of SSTC (0.88 +/- 0.40) g, (1239.66 +/- 421.93) mm3 were obviously faster than those of the high, middle concentration group of SSTC (0.22 +/- 0.14) g, (239.31 +/- 137.07) mm3; (0.20 +/- 0.16) g, (263.42 +/- 166.57) mm3 and CTX positive control group (0.20 +/- 0.10) g, (246.72 +/- 194.6) mm3 (P<0.05).</p><p><b>CONCLUSION</b>SSTC could efficiently inhibit the growth and proliferation of CNE-1 and CNE-2 in vitro, and slow down the tumor growth of the CNE-2 bearing nude mice. It may be a new compound of Chinese medicine for nasopharyngeal carcinoma therapy.</p>

Construction and identification of human bone morphogenetic protein-7 recombinant adeno-associated virus type 2 vector and its expression in bone mesenchymal stem cells / 中华外科杂志

<p><b>OBJECTIVES</b>To facilitate gene therapy research using recombinant adeno-associated virus type 2 (rAAV2) vector as gene transfer vehicle, and to construct a rAAV2 based vector carrying bone morphogenetic protein-7 (BMP7) and observe its expression in bone mesenchymal stem cells.</p><p><b>METHODS</b>The coding sequence (1.3 kb) of BMP7 was amplified by polymerase chain reaction (PCR) from the pcDNA1.1(+) plasmid containing the human BMP-7 cDNA. After purified, the gene fragment was cloned into a plasmid pUC18 and termed plasmid pUC18-hBMP7. The recombinant pUC18-hBMP7 was digested by Kpn I and Sal I and further ligated to the pSNAV by T4DNA ligase. The resultant plasmid PSNAV-hBMP7 was transformed into DH5a Escherichia coli, and positive colonies were screened by PCR and digest with restriction enzyme to identify the correct recombinant clones. BHK-21 cells were transfected with the purified pSNAV-BMP7 plasmid according to a standard calcium phosphate precipitation method. The cells were then cultured in selection media containing 800 micro g/ml G418 (Gibco/BRL). G418-resistant BHK-21 cell clones were isolated and the integrity of hBMP7 gene was determined by PCR using the above PCR primers. To package the virus, stably transfected BHK-21 cells were subsequently infected with recombinant herpes simplex virus type 1 (rHSV-1). The collected cells were processed by chloroform treatment, PEG8000/NaCl precipitation and chloroform extraction for purification. The titer was determined using quantitative DNA dot blots and the purity was examined by sodium dodecyl sulphate polyacrylamide gel electrophoresis. Following infection with rAAV2-BMP7 at multiplicities of infection of 1 x 10(5) vector genomes per cell and subsequent culture, MSCs were assessed qualitatively for BMP7 production.</p><p><b>RESULTS</b>Transient transfection showed an efficiency of 98.8% in MSCs. RT-PCR showed that MSCs had transcription of BMP7 that was enhanced by the gene transfer. BMP-7 expression in MSCs was identified by Western-blot.</p><p><b>CONCLUSIONS</b>The hBMP7 recombinant adeno-associated virus vector is successfully constructed. The present in vitro study demonstrates that rAAV2-BMP7 could infect MSCs.</p>

Repairing articular cartilage defects with tissue-engineering cartilage in rabbits / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the effect of cancellous bone matrix gelatin (BMG) engineered with allogeneic chondrocytes in repairing articular cartilage defects in rabbits.</p><p><b>METHODS</b>Chondrocytes were seeded onto three-dimensional cancellous BMG and cultured in vitro for 12 days to prepare BMG-chondrocyte complexes. Under anesthesia with 2.5% pentobarbital sodium (1 ml/kg body weight), articular cartilage defects were made on the right knee joints of 38 healthy New Zealand white rabbits (regardless of sex, aged 4-5 months and weighing 2.5-3 kg) and the defects were then treated with 2.5% trypsin. Then BMG-chondrocyte complex (Group A, n=18), BMG (Group B, n=10), and nothing (Group C, n=10) were implanted into the cartilage defects, respectively. The repairing effects were assessed by macroscopic, histologic, transmission electron microscopic (TEM) observation, immunohistochemical examination and in situ hybridization detection, respectively, at 2, 4, 8, 12 and 24 weeks after operation.</p><p><b>RESULTS</b>Cancellous BMG was degraded within 8 weeks after operation. In Group A, lymphocyte infiltration was observed around the graft. At 24 weeks after operation, the cartilage defects were repaired by cartilage tissues and the articular cartilage and subchondral bone were soundly healed. Proteoglycan and type II collagen were detected in the matrix of the repaired tissues by Safranin-O staining and immunohistochemical staining, respectively. In situ hybridization proved gene expression of type II collagen in the cytoplasm of chondrocytes in the repaired tissues. TEM observation showed that chondrocytes and cartilage matrix in repaired tissues were almost same as those in the normal articular cartilage. In Group B, the defects were repaired by cartilage-fibrous tissues. In Group C, the defects were repaired only by fibrous tissues.</p><p><b>CONCLUSIONS</b>Cancellous BMG can be regarded as the natural cell scaffolds for cartilage tissue engineering. Articular cartilage defects can be repaired by cancellous BMG engineered with allogeneic chondrocytes. The nature of repaired tissues is closest to the normal cartilage. Local administration of trypsin can promote the adherence of repaired tissues to host tissues. Transplantation of allogeneic chondrocytes has immunogenicity, but the immune reaction is weak.</p>

Analysis of the factors affecting the recurrence of giant cell tumor of bone / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the clinical factors affecting the recurrence of giant cell tumors (GCT) of bone.</p><p><b>METHODS</b>The complete data of 146 cases with GCT were reviewed. Thirteen clinical factors were analyzed by chi(2) analysis. And the related Campanacci's grade system and Jaffe's grade system was analyzed by Crosstabs analysis. Multipal factors were analyzed by Logistic regression analysis.</p><p><b>RESULTS</b>Nineteen of 146 cases recurred, and recurrence rate was 13.0%. Recurrence rates of curettage and enblock resection groups were 18.8% and 6.3% respectively. And recurrence rates of curettage with or without of extensive procedure were 12.9% and 38.9%. Five cases had lung metastasis, and two cases presented with malignant transformation. The metastasis rate and the rate of malignant transformation were 3.4% and 1.4% respectively. The two factors of surgery method and burst out of bone-envelope appearance were related with the recurrence. Moreover, Logistic regression revealed that the surgery method significantly affected the recurrence. And Campanacci's grade system and Jaffe's grade system were not related to each other.</p><p><b>CONCLUSIONS</b>Surgery method is the main factor affected the recurrence of GCT, and Campanacci's grade system or Jaffe's grade system has no prognostic value.</p>

Prognostic significance of p21(WAF1) expression in osteosarcoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the expression of p21(WAF1) gene in human osteosarcoma and their relationships with clinicopathological parameters and prognostic value.</p><p><b>METHODS</b>The p21(WAF1) gene mRNA and p21 protein expression in 45 osteosarcoma and 10 fibrous dysplasia of bone specimens were analyzed by in situ hybridization and immunohistochemistry respectively.</p><p><b>RESULTS</b>(1) The positive rate of p21 protein expression in osteosarcoma was 17.7% (8/45). (2) The expression rate in high proliferation (4/10) significantly higher than that in low proliferation (4/35) osteosarcoma (chi2 = 4.34, P < 0.05). (3) The positive rate of p21(WAF1) mRNA expression in osteosarcoma was 42.2% (19/45). The expression rate in high proliferation (6/10) significantly higher than that in low proliferation (13/35) osteosarcoma (chi2 = 20.6, P < 0.01). (4) The survival time after operation of the patients with p21(WAF1) mRNA expression were higher than that of the patients with p21(WAF1) mRNA negative expression (P < 0.05).</p><p><b>CONCLUSIONS</b>(1) With the increase in degree of malignancy, the expression of p21(WAF1) mRNA and p21 protein in osteosarcoma tend decrease. (2) The expression of p21(WAF1) mRNA has a definite value in judging prognosis in osteosarcoma.</p>

p21WAF1/CIP1 gene DNA sequencing and its expression in human osteosarcoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Mutation and expression change of p21WAF1/CIP1 may play a role in the growth of osteosarcoma. This study was to investigate the expression of the p21WAF1/CIP1 gene in human osteosarcoma, p21WAF1/CIP1 gene DNA sequence change and their relationships with the phenotype and clinical prognosis.</p><p><b>METHODS</b>p21WAF1/CIP1 gene in 10 normal people and the tumours of 45 osteosarcoma patients were examined using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) with silver staining. The PCR product with an abnormal strand was sequenced directly. The p21WAF1/CIP1 gene mRNA and P21 protein of 45 cases of osteosarcoma were investigated by using in situ hybridization and immunohistochemistry, respectively.</p><p><b>RESULTS</b>The occurrence of P21 protein in osteosarcoma was 17.78% (8/45), and p21WAF1/CIP1 mRNA expression in osteosarcoma was 42.22% (19/45). The p21WAF1/CIP1 gene DNA sequencing of amplified production showed that in p21WAF1/CIP1 gene exon 3 of 36 cases of human osteosarcoma, there were 17 cases (47.22%) with C-->T at position 609; 10 normal blood samples' DNA sequence analysis yielded 8 cases (80.00%) with C-->T at the same position.</p><p><b>CONCLUSIONS</b>Along with the increase of malignancy, the expression of p21WAF1/CIP1mRNA and P21 protein in osteosarcoma tends to decrease. It is uncommon for the p21WAF1/CIP1 gene mutation to occur in human osteosarcoma. As a result, the possible existence of tumour subtypes of p21WAF1/CIP1 gene mutation should be investigated. Our research leads to the location of p21WAF1/CIP1 gene polymorphism of Chinese osteosarcoma patients, which can provide a basis for further research.</p>