Arthroscopic debridement improves range of motion for heterotopic ossification after total knee replacement: a retrospective cohort study.

The presence of heterotopic ossification (HO) after primary total knee replacement (TKR) is rare and associated with limited mobility and stiffness of the knee. This study aimed to identify if the arthroscopic debridement after TKR could decrease HO and improve the function and range of motion. Thirty HO patients after TKR were retrospectively separated into 2 cohorts. 15 patients of group A accepted the arthroscopic debridement, while 15 patients of group B only had non-operative treatment, mainly including oral nonsteroidal anti-inflammatory drugs (NSAIDs) and rehabilitative treatment. Visual analog scale (VAS) scores, knee society knee scores (KSS), range of motion (knee flexion and knee extension) were obtained before treatment and at 1 month, 3 months, and 6 months after treatment. Radiography of after-treatment was also evaluated to assess the changes in HO. There were 3 males and 27 females with a mean age of 67.4 ± 0.8 years in group A and 68.2 ± 1.3 in group B. The onset time of HO was 3-6 months. The maximum size of the ossification was < 2 cm in 23 knees, 2 cm < heterotopic bone < 5 cm in 6 knees and > 5 cm in 1 knee. The size of HO decreased gradually in all knees by X-ray film at the last follow-up. There were no significant differences in VAS scores after replacement between two groups (p > 0.05). The average range of motion preoperatively in group A was - 15.2-90.6°, which postoperatively increased to - 4.2-110.0°. Meanwhile, the KSS scores and average range of motion of the group A were better than those of the group B at each follow-up time after treatment. Arthroscopic debridement can decrease HO seen from postoperative X-rays, improve the function and range of motion, as well as the pain remission between two groups are comparable. Consequently, arthroscopic resection of HO after TKR is recommended as soon as there is aggravating joint stiffness.

Distal tibial tubercle osteotomy can lessen change in patellar height post medial opening wedge high tibial osteotomy? A systematic review and meta-analysis.

OBJECTIVE: Medial opening wedge high tibial osteotomy (MOWHTO) is a mainstream surgical method for treating early medial compartment knee osteoarthritis. Undesirable sequelae such as patella infera may happen following tuberosity osteotomy. We conducted this systematic review and meta-analysis to compare the change in patellar position after proximal tibial tubercle osteotomy (PTO) versus distal tibial tubercle osteotomy (DTO) intervention. METHODS: The 11 studies were acquired from PubMed, Medline, Embase and Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed by RevMan5.3. Mean differences, odds ratios and 95% confidence intervals were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa Scale were used to assess risk of bias. RESULTS: Eleven observational studies were assessed. The methodological quality of the trials ranged from moderate to high. The pooled results of postoperative patellar height (Caton-Deschamps index and Blackburne-Peel index) and postoperative complications showed that the differences were statistically significant between PTO and DTO interventions. Patellar index ratios decreased significantly in the PTO groups, and 12 (9.2%) complications under DTO surgery and 2 (1.6%) complications under PTO surgery were reported. The differences of postoperative posterior tibial slope (angle) was not statistically significant, but postoperative posterior tibial slope of both groups increased. Sensitivity analysis proved the stability of the pooled results and the publication bias was not apparent. CONCLUSIONS: DTO in MOWHTO maintained the postoperative patellar height, and clinically, for patients with serious patellofemoral osteoarthritis, DTO can be preferred. Postoperative complications are easily preventable with caution. In view of the heterogeneity and small sample size, whether these conclusions are applicable should be further determined in future studies.

mRNA and long non-coding RNA expression profiles of rotator cuff tear patients reveal inflammatory features in long head of biceps tendon.

BACKGROUND: This study aimed to identify the differentially expressed mRNAs and lncRNAs in inflammatory long head of biceps tendon (LHBT) of rotator cuff tear (RCT) patients and further explore the function and potential targets of differentially expressed lncRNAs in biceps tendon pathology. METHODS: Human gene expression microarray was made between 3 inflammatory LHBT samples and 3 normal LHBT samples from RCT patients. GO analysis and KEGG pathway analysis were performed to annotate the function of differentially expressed mRNAs. The real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was admitted to verify their expression. LncRNA-mRNA co-expression network, cis-acting element, trans-acting element and transcription factor (TF) regulation analysis were constructed to predict the potential molecular regulatory mechanisms and targets for LHB tendinitis. RESULTS: 103 differentially expressed lncRNAs and mRNAs, of which 75 were up-regulated and 28 were down-regulated, were detected to be differentially expressed in LHBT. The expressions of 4 most differentially expressed lncRNAs (A2MP1, LOC100996671, COL6A4P, lnc-LRCH1-5) were confirmed by qRT-PCR. GO functional analysis indicated that related lncRNAs and mRNAs were involved in the biological processes of regulation of innate immune response, neutrophil chemotaxis, interleukin-1 cell response and others. KEGG pathway analysis indicated that related lncRNAs and mRNAs were involved in MAPK signaling pathway, NF-kappa B signaling pathway, cAMP signaling pathway and others. TF regulation analysis revealed that COL6A4P2, A2MP1 and LOC100996671 target NFKB2. CONCLUSIONS: LlncRNA-COL6A4P2, A2MP1 and LOC100996671 may regulate the inflammation of LHBT in RCT patients through NFKB2/NF-kappa B signaling pathway, and preliminarily revealed the pathological molecular mechanism of tendinitis of LHBT.

Was femoral nerve block effective for pain control of medial opening-wedge high tibial osteotomy?: A single blinded randomized controlled study.

BACKGROUND AND PURPOSE: Medial compartment femoro-tibial osteoarthritis (OA) is a common disease and opening-wedge high tibial osteotomy (OWHTO) is the common surgical procedure carried out for these patients. While most researchers are focusing on the surgical techniques during operation, the aim of this study is to evaluate the pain control effect of femoral nerve block (FNB) for OWHTO patients. METHODS: In this prospective, single-center, randomized controlled trial (RCT) study, 41 patients were operated on by OWHTO for OA during 2017 to 2018. Twenty of them (group A) accepted epidural anesthesia with FNB and 21 patients (group B) only had their single epidural anesthesia. All blocks were successful and all the 41 patients recruited were included in the analysis and there was no loss to follow-up or withdrawal. Systematic records of visual analog scores (VAS), quadriceps strength, mean number of times of patient-controlled intravenous analgesia (PCIA), using of additional opioids or nonsteroidal anti-inflammatory drugs (NSAIDs), and complications were done after hospitalization. The Student t test and Chi-Squared test was used and all P values ≤.05 were considered statistically significant. RESULTS: VAS scores at rest (3.48 ±â€Š1.0 vs 4.68 ±â€Š1.1) and on movemment (4.51 ±â€Š0.6 vs 4.97 ±â€Š0.8) decreased more in group A than group B with significance at follow-up of 12 hours. The quadriceps strength, consumption of additional opioids or NSAID injections and mean number of times that the patients pushed the PCIA button didnot differ significantly within each group. CONCLUSION: This RCT study shows that FNB in patients undergoing OWHTO for unicompartmental osteoarthritis of the knee could result in significant reduction in VAS scores at 12 hours postoperatively.Research registry, Researchregistry4792. Registered April 7, 2019 - Retrospectively registered, http://www.researchregistry.com.

Arthroscopic versus open treatment for femoroacetabular impingement: A systematic review and meta-analyses.

BACKGROUND: Femoroacetabular impingement (FAI) is a common cause of hip pain and restricted range of motion in young adults and athletes. This study aims to compare clinical results and complications between patients treated for FAI who underwent either arthroscopic or open treatment. METHODS: The 7 studies were acquired from PubMed, Medline, Embase, and Cochrane Library. The data were extracted analyzed by RevMan5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. The Newcastle-Ottawa Scale were used to assess risk of bias. RESULTS: Seven observational studies were assessed. The methodological quality of the trials indicated a low risk of bias. The pooled results of the modified Harris Hip Score (mHHS), the Non-Arthritic Hip Score (NAHS), the Visual Analogue Scale (VAS), and satisfaction rate showed that the differences were not statistically significant between arthroscopic treatment (AT) and open treatment (OT). The difference of postoperative alpha angle was statistically significant, and OT was more effective [MD = 3.08, 95% confidence interval (95% CI) = 1.45-4.70, P = .0002]. The difference of postoperative internal rotation angle was statistically significant, and OT had better internal rotation angle (MD = -3.21, 95% CI = -6.14 to -0.28, P = .03). However, the difference of complications was statistically significant and AT achieved better result than OT (OR = 0.41, 95% CI = 0.22-0.74, P =0.003). CONCLUSION: AT had comparable effect and lower complications than OT, but had less improvement in alpha angle and internal rotation angle.

Vitamin D3 protects articular cartilage by inhibiting the Wnt/ß-catenin signaling pathway.

Low expression levels of 25-hydroxyvitamin D (vitamin D3) in the blood have been reported to be associated with the progression of osteoarthritis; however, the mechanisms by which this occurs remain unclear. The present study aimed to determine the effects of vitamin D3 on chondrocytes. MTT assays were used to determine whether vitamin D3 affects chondrocytes viability. Primary chondrocytes were treated with control culture medium, vitamin D3, tumor necrosis factor (TNF)-α, TNF-α + PNU-74654 [Wingless-related integration site (Wnt)/ß-catenin signaling pathway inhibitor] or TNF-α + vitamin D3. Reverse transcription-quantitative PCR and western blotting were utilized to measure the gene and protein expression of collagen II, aggrecan, matrix metalloproteinase (MMP)-3 and MMP-13, A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4, ADAMTS-5, Wnt-3a and nuclear ß-catenin. The results demonstrated that TNF-α reduced the expression levels of aggrecan and collagen II, and increased the expression levels of MMP-3, MMP-13, ADAMTS-4 and ADAMTS-5. Furthermore, vitamin D3 and PNU-74654 were observed to partially attenuate the effects induced by TNF-α. Moreover, similar findings were reported following co-treatment with vitamin D3 and TNF-α. Western blotting data revealed that TNF-α increased Wnt-3a and ß-catenin protein levels in chondrocytes, while Vitamin D3 and PNU-74654 decreased the expression levels of Wnt-3a and nuclear ß-catenin. In conclusion, the findings of the present study provided evidence to suggest that vitamin D3 may prevent articular cartilage degeneration and osteoarthritic disease progression by inhibiting the expression levels of MMP-3, MMP-13, ADAMTS-4 and ADAMTS-5 through suppressing the Wnt/ß-catenin signaling pathway. These results suggested that vitamin D3 may be of therapeutic value for the prevention and treatment of osteoarthritis.

Arthroscopic labral debridement versus labral repair for patients with femoroacetabular impingement: A meta-analysis.

OBJECTIVE: Femoroacetabular impingement (FAI) is a common cause of hip pain and even tearing of the acetabular labrum in young adults and athletes. Either arthroscopic labral debridement (LD) or labral repair (LR) technique for FAI patients is needed to choose. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic LD versus LR intervention. METHODS: The five studies were acquired from PubMed, Medline, Embase, and Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed by RevMan5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa Scale were used to assess risk of bias. RESULTS: Four observational studies and one prospective randomized study were assessed. The methodological quality of the trials indicated a low to moderate risk of bias. The pooled results of Non-Arthritic Hip Score (NAHS), failure rate of surgeries and complications showed that the differences were not statistically significant between the two interventions. The difference of modified Harris Hip Score (mHHS), the Visual Analogue Scale (VAS) score and satisfaction rate was statistically significant between LD and LR intervention, and LR treatment was more effective. Sensitivity analysis proved the stability of the pooled results and there were too less included articles to verify the publication bias. CONCLUSIONS: Hip arthroscopy with either LR or LD is an effective treatment for symptomatic FAI. The difference of mHHS, VAS score, and satisfaction rate was statistically significant between LD and LR intervention, and arthroscopic LR could re-create suction-seal effect, potentially reduce microinstability, which demonstrated a trend toward better clinical efficacy and comparable safety compared with LD. The arthroscopic LR technique is recommended as the optical choice for acetabular labrum tear with FAI.

Opening-Wedge High Tibial Osteotomy Using Autograft versus Allograft: A Systematic Review and Meta-analysis.

Bone grafting is a good alternative for filling the inevitable void that is created following opening-wedge high tibial osteotomy (OWHTO). This systematic review and meta-analysis evaluated whether bone grafting is necessary for OWHTO and the successful outcomes of OWHTO using either autograft (AU) or allograft (AL). All analyzed studies were acquired from PubMed, Medline, Embase, CNKI, Google Scholar, and Cochrane Library. Data were independently extracted by two coauthors and were analyzed using RevMan5.3. Mean differences, odds ratios, and 95% confidence intervals were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa Scale were used to assess the risk of bias. In total, 10 studies were assessed including three randomized controlled trials and seven observational studies. The methodological quality of the trials ranged from low to high. The overall estimate demonstrated that the difference between OWHTO using AU and AL groups and OWHTO using no filling group was not statistically significant for the loss of correction, and complications, but OWHTO using no filling group statistically showed better knee society score. Pooled results of reoperations, lateral cortex breaches, complications, and clinical function assessments showed no significant difference between AU and AL materials. Using AL statistically reduced the operative time compared with using AU. OWHTO with or without bone graft does not affect postoperative complications. No loss of correction was observed due to the lack of bone grafting. In addition, OWHTO without bone graft performs better for postoperative clinical function assessment. Complications and clinical results of medial OWHTO were similar using AL and AU and neither reported a median loss of correction of following OWHTO. Compared with using AU, using AL avoids harvest site complications and reduces operative time. To sum up, OWHTO without any bone graft is recommended for medial unicompartmental osteoarthritis of the knee. Further large-sample, multicenter, high-quality, randomized controlled trials are warranted to verify the outcomes of this meta-analysis.

Comparison of arthroscopic suture-bridge technique and double-row technique for treating rotator cuff tears: A PRISMA meta-analysis.

BACKGROUND: Rotator cuff tear is a common shoulder disorder in the elderly. Either arthroscopic double-row (DR) or suture-bridge (SB) technique for rotator cuff tear patients is needed to choose. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic SB versus DR intervention. METHODS: The 7 studies were acquired from PubMed, Medline, Embase, CNKI, Google, and Cochrane Library. The data were extracted by 2 of the co-authors independently and were analyzed by RevMan5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa scale were used to assess risk of bias. RESULTS: Seven studies including 1 randomized controlled trial and 6 observational studies were assessed. The methodological quality of the trials ranged from low to moderate. The pooled results of American Shoulder and Elbow Surgeons score, Constant score, visual analog scale score, and range of motion showed that the differences were not statistically significant between the 2 interventions. The difference of University of California at Los Angeles (UCLA) score was statistically significant between SB and DR intervention, and SB treatment was more effective (MD = -0.95, 95% CI = -1.70 to -0.20, P = .01). The difference of re-tear rate was statistically significant and SB treatment achieved better result than DR treatment (OR = 0.31, 95% CI = 0.15-0.64, P = .001). Sensitivity analysis proved the stability of the pooled results and the publication bias was not apparent. CONCLUSIONS: Both arthroscopic SB and DR interventions had benefits in rotator cuff tear. SB treatment was more effective in UCLA score and had lower re-tear rate than DR treatment. The arthroscopic SB technique is recommended as the optical choice for rotator cuff tear.

Is arthroscopic repair superior to biceps tenotomy and tenodesis for type II SLAP lesions? A meta-analysis of RCTs and observational studies.

OBJECTIVE: Labral repair and biceps tenotomy and tenodesis are routine operations for type II superior labrum anterior posterior (SLAP) lesion of the shoulder, but evidence of their superiority is lacking. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic repair versus biceps tenotomy and tenodesis intervention. METHODS: The eight studies were acquired from PubMed, Medline, Embase, CNKI, and Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed by RevMan 5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa Scale were used to assess risk of bias. RESULTS: Eight studies including two randomized controlled trials (RCTs) and six observational studies were assessed. The methodological quality of the trials ranged from low to moderate. The pooled results of UCLA score, SST score, and complications showed that the differences were not statistically significant between the two interventions. The difference of ASES score and satisfaction rate was statistically significant between arthroscopic repair and biceps tenotomy and tenodesis intervention, and arthroscopic biceps tenotomy and tenodesis treatment was more effective. Sensitivity analysis proved the stability of the pooled results, and there were too less included articles to verify the publication bias. CONCLUSIONS: Both arthroscopic repair and biceps tenotomy and tenodesis interventions had benefits in type II SLAP lesions. Arthroscopic biceps tenotomy and tenodesis treatment provides better clinical outcome in ASES score and satisfaction rate and comparable complications compared with arthroscopic repair treatment. In view of the heterogeneity and confounding factors, whether these conclusions are applicable should be further determined in future studies.

Bioinformatics analysis of differentially expressed genes in rotator cuff tear patients using microarray data.

BACKGROUND: Rotator cuff tear (RCT) is a common shoulder disorder in the elderly. Muscle atrophy, denervation and fatty infiltration exert secondary injuries on torn rotator cuff muscles. It has been reported that satellite cells (SCs) play roles in pathogenic process and regenerative capacity of human RCT via regulating of target genes. This study aims to complement the differentially expressed genes (DEGs) of SCs that regulated between the torn supraspinatus (SSP) samples and intact subscapularis (SSC) samples, identify their functions and molecular pathways. METHODS: The gene expression profile GSE93661 was downloaded and bioinformatics analysis was made. RESULTS: Five hundred fifty one DEGs totally were identified. Among them, 272 DEGs were overexpressed, and the remaining 279 DEGs were underexpressed. Gene ontology (GO) and pathway enrichment analysis of target genes were performed. We furthermore identified some relevant core genes using gene-gene interaction network analysis such as GNG13, GCG, NOTCH1, BCL2, NMUR2, PMCH, FFAR1, AVPR2, GNA14, and KALRN, that may contribute to the understanding of the molecular mechanisms of secondary injuries in RCT. We also discovered that GNG13/calcium signaling pathway is highly correlated with the denervation atrophy pathological process of RCT. CONCLUSION: These genes and pathways provide a new perspective for revealing the underlying pathological mechanisms and therapy strategy of RCT.

Exploring the Key Genes and Pathways of Osteoarthritis in Knee Cartilage in a Rat Model Using Gene Expression Profiling.

PURPOSE: To compare differentially expressed genes (DEGs) mediating osteoarthritis (OA) in knee cartilage and in normal knee cartilage in a rat model of OA and to identify their impact on molecular pathways associated with OA. MATERIALS AND METHODS: A gene expression profile was downloaded from the Gene Expression Omnibus database. Analysis of DEGs was carried out using GEO2R. Enrichment analyses were performed on the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway using the Search Tool for the Retrieval of Interacting Genes database (http://www.string-db.org/). Subsequently, the regulatory interaction network of OA-associated genes was visualized using Cytoscape software (version 3.4.0; www.cytoscape.org). RESULTS: In the gene expression profile GSE103416, a total of 99 DEGs were identified. Among them, 76 DEGs (76.77%) were overexpressed, and the remaining 23 DEGs (23.23%) were underexpressed. GO and pathway enrichment analyses of target genes were performed. Using gene-gene interaction network analysis, relevant core genes, including MET, UBB, GNAI3, and GNA13, were shown to hold a potential relationship with the development of OA in cartilage. Using quantitative real-time PCR, the Gna13/cGMP-PKG signaling pathway was identified as a potential research target for therapy and for further understanding the development of OA. CONCLUSION: The results of the present study provide a comprehensive understanding of the roles of DEGs in knee cartilage in relation to the development of OA.

Exploring the key genes and pathways of side population cells in human osteosarcoma using gene expression array analysis.

BACKGROUND: Human osteosarcoma (OS) is one of the most common primary bone sarcoma, because of early metastasis and few treatment strategies. It has been reported that the tumorigenicity and self-renewal capacity of side population (SP) cells play roles in human OS via regulating of target genes. This study aims to complement the differentially expressed genes (DEGs) that regulated between the SP cells and the non-SP cells from primary human OS and identify their functions and molecular pathways associated with OS. METHODS: The gene expression profile GSE63390 was downloaded, and bioinformatics analysis was made. RESULTS: One hundred forty-one DEGs totally were identified. Among them, 72 DEGs (51.06%) were overexpressed, and the remaining 69 DEGs (48.94%) were underexpressed. Gene ontology (GO) and pathway enrichment analysis of target genes were performed. We furthermore identified some relevant core genes using gene-gene interaction network analysis such as EIF4E, FAU, HSPD1, IL-6, and KISS1, which may have a relationship with the development process of OS. We also discovered that EIF4E/mTOR signaling pathway could be a potential research target for therapy and tumorigenesis of OS. CONCLUSION: This analysis provides a comprehensive understanding of the roles of DEGs coming from SP cells in the development of OS. However, these predictions need further experimental validation in future studies.

Short-term Follow-up of Antibiotic-loaded Articulating Cement Spacers in Two-stage Revision of Infected Total Knee Arthroplasty: A Case Series.

OBJECTIVE: Infection of total knee arthroplasty (TKA) is a rare but devastating complication. Two-stage revision is an effective treatment for late infected TKA. This study aimed to assess the short-term results of two-stage revision using articulating antibiotic-loaded spacers. METHODS: Twenty-five patients (10 men and 15 women) were diagnosed with late infections after TKA and treated with two-stage revision from April 2006 to August 2010; 19 of these patients had TKA for osteoarthritis and 6 for rheumatoid arthritis. Median age was 64.9 (range, 56-83) years. In the first-stage surgery, the prosthesis and all bone cement was removed. After thorough debridement, bone cement with vancomycin and tobramycin was put into a die cavity and made into temporary femoral and tibial spacers, respectively. In the cases of good knee range of motion, the temporary spacers were affixed to the bone surface using the same antibiotic bone cement. In the second surgery, gentamycin Refobacin Bone Cement with vancomycin was used to fix the prosthesis. After two-stage revision, patients were followed up clinically and radiologically at 1, 3, and 6 months, and then annually. Knee Society Score (KSS), knee function score, knee pain score, and knee range of motion (ROM) were assessed. RESULTS: Among the group, all spacers were easily removed, and bone defect degree showed no obvious change compared with pre-implant, 24 (96%) patients had been debrided once, and 1 patient had been debrided twice before reimplant prosthesis. Mean follow-up was 64.2 (range, 52-89) months. There was no infection recurrence at final follow-up. Compared with preoperative data, the KSS (66 [59, 71], 83 [80, 88] vs 46 [43, 57], P < 0.01), knee function score (43 [42, 49], 78 [73, 82] vs 32 [25, 37], P < 0.01), knee pain score (34 [33, 37], 42 [40, 45] vs 18 [16, 23], P < 0.01), and knee ROM (92° [86°, 96°], 94° [90°, 98°] vs 78° [67°, 86°], P < 0.01) were all improved during follow-up and at final visit. Three patients experienced complications in the interval period: one case had knee dislocation, one had knee instability, and one had a chip in the femoral component of the spacer. CONCLUSION: Using articulating antibiotic-loaded spacers showed benefits for treating infected TKA in selected patients. No infection recurrence was observed during follow-up.

Antibiotic-loaded articulating cement spacers in two-stage revision for infected total knee arthroplasty: individual antibiotic treatment and early results of 21 cases.

OBJECTIVE: To detail our early experience and technique of a modified two-stage reimplantation protocol using antibiotic-loaded articulating cement spacers (ALACSs) for treatment of late periprosthetic infection after total knee arthroplasty (TKA). METHODS: From January 2006 to February 2009, a series of 21 patients (21 knees) with late infected TKAs were treated by radical debridement and removal of all components and cement, and then articulating spacers were implanted using antibiotic-impregnated bone cement. For this purpose, 4 g vancomycin powder was mixed with per 40 g cement. Graduated knee motion and partial weight bearing activity were encouraged in the interval period. Each patient received an individual systemic organism-sensitive antimicrobial therapy for 4.9 (range, 2-8) weeks followed by a second-stage TKA revision. All the patients were regularly followed up using the American Knee Society Scoring System. RESULTS: Each case underwent a successful two-stage exchange and had infection eradicated, none had recurrent infection after an average of 32.2 (range, 17-54) months of follow-up. Preoperatively, the mean knee score was 53.5 points, function score was 27.3 points, pain score was 25.7 points, range of motion (ROM) was 82.0 degree extensor lag was 2 degree Between stages, the mean knee score was increased to 61.3 points, function score to 45 points, pain score to 35 points, ROM to 88.2 degree and extensor lag to 3.4 degree At final follow-up, the mean knee score was further increased to 82.1 points, function score to 74.5 points, pain score to 42.1 points, ROM to 94.3 degree and knee extension lag to 1.9 degree The interval period was 11.5 (range, 6-32) weeks. The amount of bone loss was unchanged between stages. No patient developed noticeable dysfunction of the liver or kidney or other complications such as impaired wound healing, deep venous thrombosis, pulmonary embolism, cerebrovascular accidents, etc. CONCLUSIONS: Treating infected TKA with ALACS avoids spacer-related bone loss, preserves knee function between stages, and eradicates infection effectively without significant complications. The early clinical results are inspiring. The authors believe that radical and repeated (if needed) debridement, individual application of systemic antibiotics, and reasonable timing judgement upon the secondary revision are all key factors related to a successful outcome with two-stage reimplantation procedure for infected TKA.

[Autologous bone grafting plus screw fixation for medial tibial defects in total knee arthroplasty].

OBJECTIVE: To investigate the efficacy of autologous bone grafting plus screw fixation to reconstruct the medial tibial defects in total knee arthroplasty (TKA). METHODS: From November 2001 to November 2004, 46 patients (50 knees) with medial tibial bone defects underwent TKA at our hospital. There were 16 males (16 knees) and 30 females (34 knees). They included osteoarthritis (OA) (n = 35, 38 knees) and rheumatoid arthritis (RA) (n = 11, 12 knees). A total of 46 patients underwent three-dimensional CT (computed tomography) reconstruction to evaluate the tibial plateau defects after osteotomy. Single or double distal femoral osteotomic bone was used to reconstruct the bone defects with the hollow nail internal fixation. Another 80 TKA patients (86 knees) were randomly selected as the control group. The surgical outcome, lateral migration of tibial component and joint line elevation, etc. were analyzed and the follow-up knee society scores recorded. RESULTS: The patients were followed up for 6 to 9 years. Two patients were lost to follow-up and 1 died of myocardial infarction at 5 years post-TKA in the test group. In the last follow-up, 1 case suffered deep infections and all others had no prosthetic loosening. One case (1 knee) had resorption of wedge-shaped bone graft after 8 years. The remaining graft healed and there was no screw displacement. Medial platform split fracture occurred in 3 patients (3 knees) in the OA group. The quantity of distal femoral osteotomy, thickness of polyethylene insert, tibial implant size, joint line elevation and lateral migration of tibial base were greater than the other two groups (q test, P < 0.05). The pre- and post-operative KSS scores had significant differences in each group (F test, P < 0.05). But the same group showed no significant difference at 6, 9 years (q test, P > 0.05). CONCLUSION: As an easy and effective way of reconstructing the medial tibial bone defects, autologous bone grafting plus screw fixation can restore knee mechanical axis and stability. But in OA patients with tibial sclerosis, the complications of tibial component lateral migration, joint line elevation and splitting tibia fractures should be avoided during the reconstruction.

[Management of postoperative pain after total knee arthroplasty].

OBJECTIVE: To evaluate causes and clinical management of postoperative pain after total knee arthroplasty (TKA). METHODS: From January 2004 to June 2009, 41 patients (44 knees) with knee pain post TKA were treated. There were 9 male and 32 female patients aging from 51 to 84 years with a mean of 63.5 years. The diagnosis followed to Brown diagnostic system. One case of extraarticular pain was complex regional pain syndrome type 1 (CRPS-1) and underwent conservative treatment, the remaining 5 cases were treated by surgery. Three cases of joint instability, 1 case of patellar baja, 2 cases of soft tissue impingement caused by overhang of the prosthesis, 1 case of popliteal tendon impact underwent conservative treatment, the other 27 cases underwent surgical intervention. The patients were followed up and the Knee Society Score (KSS) knee score, pain visual analog scale (VAS) score were recorded. RESULTS: Forty-one cases were followed up for 1 to 6 years. At the last time of follow-up, the 5 cases received surgical treatment to extra-articular pain showed VAS score as 2.5 ± 0.2, KSS clinical and functional score as 92.8 ± 2.6 and 89.0 ± 3.4. There was significantly difference compared with preoperative (P < 0.05). One case of CRPS-1 performed conservative treatment, the therapy was effective. In the infected 12 cases of intra-articular pain, 1 case received amputation, 3 cases received antibiotic bone cement insert, 8 cases received two stage revision. All infections were cured, and VAS score was 3.8 ± 0.2, KSS clinical score was 88.3 ± 4.6, function score was 85.0 ± 4.6 postoperatively, with significantly difference compared with preoperative (P < 0.05). In the 8 cases received conservative treatment in non-infected group, at the last time of follow-up, VAS score was 4.5 ± 0.4, KSS clinical and functional score was 85.4 ± 4.2 and 84.2 ± 2.3, with significantly difference compared with preoperative (P < 0.05). Fifteen cases underwent surgical treatment, at the last time of follow-up, VAS score was 3.4 ± 0.1, KSS clinical and functional score was 86.6 ± 5.4 and 87.1 ± 2.4, with significantly difference compared with preoperative (P < 0.05). CONCLUSIONS: Patients with knee pain post TKA need systematic assessment to identify the causes. Appropriate treatment due to the positive diagnosis generally lead to satisfactory results, surgical intervention with indefinite causes is strictly prohibited.

[Effect of posterior condylar offset on knee flexion after high-flex posterior-stabilized total knee arthroplasty].

OBJECTIVE: To determine the effect of the posterior condylar offset (PCO) on intra- and post-operative knee flexion after total knee arthroplasty (TKA) using a high-flex posterior-stabilized (PS) fixed-bearing prosthesis and to discuss it's importance in femoral prosthesis design. METHODS: The clinical and radiographic materials of 100 consecutive patients (100 knees) were prospectively studied, including 50 men and 50 women, who had undergone primary NexGen LPS-Flex TKAs for end-stage osteoarthritis. All operations were performed by a single surgeon using the same operative technique between March 2005 and October 2006. Pearson's regression analysis was used to assess the relationship between the difference in the pre- and post-operative PCO on true lateral radiographs and the change in knee range of flexion (ROF) under non-weight-bearing conditions. RESULTS: The decrease of the corrected PCO was (3.4 ± 3.3) mm compared with the preoperative value, the restoration of PCO was better in male than female [female (-5.4 ± 3.1) mm vs. male (-1.5 ± 2.0) mm, P < 0.05]. The difference in the corrected PCO after PS TKA demonstrated significantly correlated with the change in 2 years postoperative ROF in male and female, respectively (P < 0.05). While no statistically correlation was observed in the overall group (P > 0.05). Intraoperatively, the difference in the corrected PCO was significantly correlated with the change in ROF in male, female, and the overall group, respectively (P < 0.05). CONCLUSIONS: Restoration of PCO plays an important role in the optimization of knee flexion after high-flex PS TKA. Femoral components based on Caucasian anatomic characteristics could not match the native anatomy of distal femurs of Chinese population especially female Chinese. Rotated resection of distal femur with anterior referencing technique usually leads to a decreased PCO and therefore reduces maximal obtainable flexion. Sexual dimorphism in humans and anatomic variations in various ethnic groups should be seriously considered in total knee prosthesis design.