Partial two?stage exchange for periprosthetic joint infection after total hip arthroplasty / 中华骨科杂志

Objective To evaluate the early stage effects of partial two?stage exchange (PTE) for infection after total hip arthroplasty (THA) in order to improve surgical treatment outcomes. Methods Twelve patients (7 males and 5 females) of infect?ed THA treated by PTE between September 2000 and February 2016 were included with an average of 59 years old (range, 40-74 years old). The femoral stem prosthesis was preserved when we ensured that it was not infected and with well fixation during opera?tion. The acetabular prosthesis was totally replaced. Furthermore, the secondary surgery was performed on patients who were free from infection for at least 3 months. At the follow?up duration, the pelvic X?ray was examined to access the presence of loosening of the prosthesis. The inflammatory index was recorded. Hip function was assessed by the Harris hip score, and the visual analogue score (VAS) and patient's subjective satisfaction were recorded by the questionnaire. Results All of the 12 patients were fol?lowed up for a mean of 33.3 months (range, 24-48 months). We achieved a 92% (11/12) success rate. One patient resuffered infec?tion, which was controlled after the second debridement. The preoperative Harris score of 12 patients was 23-57, with an average of 40.83±10.62. All patients had significant improvement in hip function after PTE. The Harris score reached 59.58±4.34 at one month after surgery, and reached 64.58±9.08 after three months and 86.75±4.58 at the last follow?up. There was significantly dif?ferent when compared with the preoperative Harris score. At the last follow?up, the length difference between the lower limbs was less than 1cm in all patients. Two patients did not complain of pain, while other 10 patients got a VAS score of less than 2 points. The patient's subjective satisfaction rating was 100%. Conclusion PTE could be a valuable alternative treatment for infection af?ter THA. The infection control rate and clinical outcomes are comparable to those of two?stage exchange.

Value of knee skin temperature and serum soluble intercellular adhesion molecule-1 level in the diagnosis of peri-prosthetic infection after total knee arthroplasty / 中华骨科杂志

Objective To investigate the diagnostic value of knee skin temperature and serum soluble intercellular adhesion molecule-1 (sICAM-1) level in peri-prosthetic infection after total knee arthroplasty (TKA).Methods Thirty patients (11 males and 19 females,aged 59.3±9.5 years old) underwent primary TKA during November 2012 and October 2015.Ten patients with peri-prosthetic infection (3 males and 7 females,aged 60.9±8.2 years old) underwent two-stage revision TKA from November 2012 to October 2015.The interleukin-6 (IL-6),C-reactive protein (CRP),erythrocyte sedimentation rate (ESR),sICAM-1 in serum and the skin temperature in knee joint were recorded preoperatively (revision patients on diagnosis),at days 1,7 and at 1,3,6,12 months post-operatively.Results All of the 40 patients were followed up for 12 months.The serum CRP,IL-6 and ESR levels in the primary TKA group were normal preoperatively and increased after operation,reaching their peaks at 1-7 days postoperatively.These indexes then returned slowly to the normal levels within 3 months.The serum sICAM-1 level in the primary TKA group did not change significantly during the follow up.The serum levels of CRP,IL-6,ESR,and sICAM-1 in the revision group were significantly higher than that in the primary TKA group preoperatively (P＜0.05),IL-6,CRP,ESR returned slowly to the normal levels within 3 months after the second-stage revision,while the level of sICAM-1 returned to normal within 3 months after the first-stage revision.During whole follow-up after the second-stage revision,the level of sICAM-1 didn't change significantly.The preoperative mean differential temperature (MDT) in the primary TKA group was 0.73±0.62 ℃ preoperatively and elevated to 4.37±1.06 ℃ at 7 days postoperatively,which returned to the baseline within 6 months after primary TKA.The preoperative MDT in the revision group was 5.03±0.81 ℃,which was significantly higher than that in the primary TKA group (P＜0.05).The MDT returned to the normal level within 6 months after the second-stage revision TKA.Conclusion The change of MDT is in accordance with serum CRP,IL-6,and ESR,which together may predict the occurrence of infection.Serum sICAM-1 level may also be valuable in the diagnosis of peri-prosthetic infection.

The treatment of patellofemoral arthroplasty for isolated patellofemoral osteoarthritis / 中华骨科杂志

Objective To explore the effect and factors of patellofemoral arthroplasty (PFA) for isolated patellofemoral osteoarthritis.Methods Data of 18 patients (3 males,15 females) with isolated patellofemoral osteoarthritis underwent PFA from March 2006 to December 2014 were retrospectively analyzed.There were 3 males and 15 females with a mean age of 54 years (range,46-74 years).It was strict to grasp the surgical indications according to the clinical symptoms,signs and imaging data preoperatively.11 patients were operated with AVON patellofemoral prosthesis (Stryker Inc.) and the other 7 patients were operated with the Gender Solutions patellofemoral prosthesis (Zimmer Inc.).Active and passive functional rehabilitation exercise was encouraged at the early stage after operation.Visual analogue scale (VAS) was 5.33±0.99 (range,4-7) and hospital for special surgery knee score (HSS) was 53.28±5.71 (range,44-63) before operation.Results The mean duration of follow-up was 63.98 months (range,6-104 months).VAS after operation for 1 and 3 months were 1.17±0.79 (range,0-3) and 0.72±0.67 (range,0-2),and the pain was almost relieved after 9 months.HSS after operation for 1,3,9 months were 70.06±6.33 (range,61-80),86.06±5.12 (range,77-95) and 91.39±4.83 (range,82-97).HSS score of the latest follow-up was 92.06±4.05 (range,84-97),which was improved obviously from the preoperative ones.The excellent and good rate was 100％ (excellent 15 cases,good 3 cases).The satisfactory rate was 94.4％ (17/18).Only one case got slightly knee pain when walking up and down the stairs after 2 years,and the pain was relieved after being administered with NSAIDs and rest.No incision infection,rupture,prosthesis supported bone fracture,prosthesis loosening and other complication was occurred during the follow-up period in the other patients.Conclusion The clinical outcomes of PFA are strictly related to surgical indications,implant design and appropriate surgical technique.Therefore,based on the appropriate PFA implants,strict surgical indications,appropriate patients,excellent operation skills and actively functional rehabilitation exercise,PFA could treat the isolated patellofemoral osteoarthritis effectively.

Value of knee skin temperature measured by infrared thermography and soluble intercellular adhesion molecule-1 in the diagnosis of peri-prosthetic knee infection in Chinese individuals following total knee arthroplasty / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Total knee arthroplasty (TKA) is a successful and frequently performed procedure in orthopedic surgery. The diagnosis of peri-prosthetic joint infection following TKA remains challenging. The present study estimated the usefulness of knee skin temperature (measured by infrared thermography) and serum soluble intercellular adhesion molecule-1 (sICAM-1) in the diagnosis of post-operative knee peri-prosthetic infection.</p><p><b>METHODS</b>Patients were divided into three groups: 21 patients undergoing uncomplicated TKAs, seven with prosthesis infection, and three undergoing TKA revisions. The serum levels of interleukin-6 (IL-6), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and sICAM-1 as well as the local knee skin temperature were measured pre-operatively and on Days 1 and 7 and at 1, 3, and 6 months post-operatively in Groups 1 and 3. The same parameters were measured in Group 2 at the time of prosthesis infection diagnosis.</p><p><b>RESULTS</b>In Group 1, the levels of IL-6, CRP, ESR, and knee skin temperature were significantly elevated post-operatively, but returned to baseline levels within 6 months. The sICAM-1 levels were not significantly different. The mean differential temperature (MDT) and levels of siCAM-1, IL-6, CRP, and ESR differed significantly between Groups 1 and 2. The MDT had returned to normal in Group 3 by 6 months post-operatively.</p><p><b>CONCLUSIONS</b>Elevations in IL-6, CRP, ESR, and MDT in patients undergoing TKA could be a normal response to surgical trauma, but sustained elevations may be indicative of complications. The knee skin temperature and sICAM-1 may be used as indicators in the diagnosis of knee prosthesis infection following TKA.</p>

Enhanced integrin-mediated human osteoblastic adhesion to porous amorphous calcium phosphate/poly (L-lactic acid) composite / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The initial osteoblastic adhesion to materials characterizes the first phase of cell-material interactions and influences all the events leading to the formation of new bone. In a previous work, we developed a novel amorphous calcium phosphate (ACP)/poly(L-lactic acid) (PLLA) material that demonstrated morphologic variations in its microstructure. The aim of this study was to investigate the initial interaction between this material and osteoblastic cells. Cellular attachment and the corresponding signal transduction pathways were investigated.</p><p><b>METHODS</b>A porous ACP/PLLA composite and PLLA scaffold (as a control) were incubated in fetal bovine serum (FBS) containing phosphate-buffered saline (PBS), and the protein adsorption was determined. Osteoblastic MG63 cells were seeded on the materials and cultured for 1, 4, 8, or 24 hours. Cell attachment was evaluated using the MTS method. Cell morphology was examined using scanning electron microscopy (SEM). The expression levels of the genes encoding integrin subunits α1, α5, αv, β1, focal adhesion kinase (FAK), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were determined using real-time reverse transcription polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The ACP/PLLA material significantly increased the protein adsorption by 6.4-fold at 1 hour and 2.4-fold at 24 hours, compared with the pure PLLA scaffold. The attachment of osteoblastic cells to the ACP/PLLA was significantly higher than that on the PLLA scaffold. The SEM observation revealed a polygonal spread shape of cells on the ACP/ PLLA, with the filopodia adhered to the scaffold surface. In contrast, the cells on the PLLA scaffold exhibited a spherical or polygonal morphology. Additionally, real-time RT-PCR showed that the genes encoding the integrin subunits α1, αv, β1, and FAK were expressed at higher levels on the ACP/PLLA composite.</p><p><b>CONCLUSIONS</b>The ACP/PLLA composite promoted protein adsorption and osteoblastic adhesion. The enhanced cell adhesion may be mediated by the binding of integrin subunits α1, αv, and β1, and subsequently may be regulated through the FAK signal transduction pathways.</p>

Acetabular revision using an anti-protrusion cage in patients with periprosthetic acetabular bone loss / 中华骨科杂志

Objective To investigate the risk factors related to the survival time of anti-protrusion cage in acetabular revision.Methods Data of 40 patients who had received acetabular revision using antiprotrusion cages between January 2002 and June 2010 were retrospectively analyzed.There were 16 males and 24 females,aged from 22 to 77 years (average,60.3 years).All patients were followed up for 12 to 82 months (average,39.2 months).According to the AAOS classification,there were 29 cases of type C and 11 cases of type D； while according to the Paprosky classification,there were 29 cases of type ⅢA and 11 cases of type Ⅲ B.The multiple regression analysis was utilized to investigate the relationships between different factors and anti-protrusion cage failure.The corresponding factors included gender,age,bone loss classification,superior or lateral migration of acetabular center of rotation,abduction angle,fixation manners (simple flange fixation or flange fixation plus transacetabular screw fixation),bone grafting techniques and cup type.Results At final follow-up,the average Harris score was 74.5±15.4.Two patients received rerevision due to prosthetic loosening.Obvious radiological loosening of prosthesis combined with pain was found in 2 cases.The statistical analysis indicated that superior migration of acetabular center of rotation,abduction angle and fixation manners were correlated with cup failure,especially when the superior migration was more than 8.5 mm or the abduction angle was larger than 53.5°.Flange fixation plus transacetabular screw fixation could reduce risk of cup failure.Conclusion There is a higher cup failure risk in acetabular revision using an anti-protrusion cage for patients with serious bone defect.However,implanting cup at the level of the true acetabulum as far as possible,decreasing abduction angle properly and using flange fixation plus transacetabular screw fixation can reduce cup failure risk.

Comparison of anterior knee pain after total knee arthroplasty using Genesis Ⅱ and PFC knee prostheses / 中华骨科杂志

Objective To explore relationship between anterior knee pain after total knee arthroplasty and patella resurfacing and prosthesis design,and to evaluate which femoral prosthesis is more friendly with patella:Genesis Ⅱ or PFC knee prostheses.Methods Data of 145 patients (145 knees) who had undergone primary total knee arthroplasty for treating osteoarthritis were retrospectively analyzed.Posterior-cruciate-substituting total knee prostheses were used in all patients.Among 74 patients who had undergone patella resurfacing,Genesis Ⅱ knee prosthesis was used in 32 patients and PFC knee prosthesis in 42 patients.Among 71 patients who had not undergone patella resurfacing,Genesis Ⅱ knee prosthesis was used in 38 patients and PFC knee prosthesis in 33 patients.The Hospital for Special Surgery(HSS) score,patella score,patellar function score,range of motion of knee,anterior knee pain scale,and patient satisfaction were used to evaluate clinical outcomes.At the same time,the imaging results were evaluated by X-rays.Results 144 patients were successfully followed up for 21 to 43 months (average,33 months).There was no significant difference in incidence of anterior knee pain between the group with patella resurfacing and the group without patella resurfacing,while a significant difference was found between patients receiving Genesis Ⅱ knee prosthesis and those receiving PFC knee prosthesis.Four patients who had undergone total knee arthroplasty using PFC prosthesis underwent reoperation.There were no significant differences in postoperative HSS score,range of motion of knee and patient satisfaction between the Genesis Ⅱ group and the PFC group,while there were significant differences in patella score and patellar function score between them.Conclusion Postoperative anterior knee pain was related to the prosthesis design,rather than to the patella resurfacing.Genesis Ⅱ knee prosthesis was more friendly with patella than PFC knee prosthesis.

Effects of glucocorticoids on fracture healing in rats / 中国病理生理杂志

AIM: To explore the effects of glucocorticoids on fracture healing in a rat model of tibial fracture. METHODS: Sixty three months old female SD rats were divided into control and glucocorticoid-treated group. A glucocorticoid-induced osteoporosis model was established by intramuscular injection of prednisolone acetate (5 mg·kg~(-1)·d~(-1) for 3 weeks), in which the tibial was osteotomized by a wire saw as fracture healing model and internal fixed with a Kirschner pin. The rats were scarified at different time points after operation. The callus formation was monitored over a period of 6 weeks by histological method, bone mineral density (BMD) detection and biomechanical examination. Western blotting was used to measure the expression of type II collagen. RESULTS: A glucocorticoid-induced osteoporosis model was successfully established and conformed by BMD measurement. The formation of primary callus was observed in both groups 3 days after fracture. At 2 weeks after injury, the glucocorticoid-treated group had a lower BMD and less cartilage matrix as compared to control group. An increase in bone callus and chondrogenesis was observed at 4 to 6 weeks after fracture in glucocorticoid-treated group as compared to control group. The expression of type II collagen was delayed in glucocorticoid-treated group. Biomechanical measurement showed that the actual maximum load was increased by 35.8% in control group as compared to glucocorticoid-treated group at 6th week. CONCLUSION: These results indicate that chondrogenesis and transformation from cartilage callus to bony callus are delayed by glucocorticoids. The retardation of collagen Ⅱ production may be the reason for the inhibition of fracture healing.

Finite element analysis of femoral stress changes after total hip arthroplasty / 中华骨科杂志

Objective To determine the biomechanical variation in full-length femoral stress pat-tern and periprosthetic femoral stress distribution after implantation either with Charnley Elite cemented prostlesis or Summit proximal porous cementless femoral prosthesis. Methods Three-dimensional finite element models of intact femur, Charnley Elite and Summit femoral prostheses were developed. The stress distributions on the femur and the implants were measured. Applied with hip joint loading and related muscles strength, the stress changes of an intact femur and those implanted with either Charnley Elite or Summit protheses, especially changes in proximal femur, were respectively quantitatively analysed. Results Com-pared with intact femur, there was no change of the full-length femur stress pattern in implantation of both implants, the areas of peak values were all presented at middle and lower regions of the femur, and femoral stress value levels were decreased with both implants. Both prostheses induced significant decrease of stress in the periprosthetic bone tissue, the most serious loss of stresses all appeared at femoral calcar, the stress-shielding rates of Elite and Summit prostheses were 90.8% and 95.3% respectively. The distributions of stress shielding of both prostheses were consistent each other, the Summit proximal porous cementless pros-thesis had more serious stress decrease than the Charnley Elite cemented prosthesis. Conclusion Implan-tation of both implants may cause significant stress shielding in the proximal femur. This may be related with periprosthetic bone loss and aseptic loosening of stems, and can be used to explain the mechanism of post-operative femoral fracture and thigh pain. Both implants designs need further improvement to reduce stress changes in proximal femur.