Intraoperative Surgeon-Performed versus Conventional Anesthesiologist-Performed Continuous Adductor Canal Block in Total Knee Arthroplasty: A Randomized Controlled Trial

A continuous adductor canal block (cACB) for pain control in total knee arthroplasty (TKA) is always performed by an anesthesiologist. A surgeon-performed cACB during surgery is somewhat questionable in terms of feasibility, reproducibility, and efficacy. This study was divided into two phases. In Phase 1 study, an experimental dissection of 16 cadaveric knees to expose the saphenous nerve and related muscles around the adductor canal was conducted. The extent of dye after injection via a catheter inserted into the adductor canal at the time of TKA was evaluated. In Phase II, a randomized controlled trial study comparing clinical outcomes between surgeon-performed (Group 1) and anesthesiologist-performed cACB (Group 2) during TKA in 63 patients was evaluated. The visual analogue scale (VAS) at rest and during movement at several time points and functional outcomes during hospitalization were compared. The Phase I study demonstrated surgeon-performed cACB during surgery feasible and reproducible with consistent dye extension into the adductor canal after injection via a catheter. In the Phase II study, 29 patients of Group 1 and 30 patients of Group 2 completed the evaluation with no differences in baseline parameters. The VAS during movement at 24 and 36 hours, quadriceps strength, time up and go test, and knee motion at different time points, and total morphine consumption showed no differences between both groups. There were no procedure-related complications. The surgeon-performed cACB during surgery was feasible and reproducible with similar VAS scores and functional outcomes during hospitalization to anesthesiologist cACB. Level of evidence is Level I, prospective randomized trial.

Infrapatellar fat pad adipose tissue-derived macrophages display a predominant CD11c+CD206+ phenotype and express genotypes attributable to key features of OA pathogenesis

Objectives

In knee osteoarthritis (OA), macrophages are the most predominant immune cells that infiltrate synovial tissues and infrapatellar fat pads (IPFPs). Both M1 and M2 macrophages have been described, but their role in OA has not been fully investigated. Therefore, we investigated macrophage subpopulations in IPFPs and synovial tissues of knee OA patients and their correlation with disease severity, examined their transcriptomics, and tested for factors that influenced their polarization.

Methods

Synovial tissues and IPFPs were obtained from knee OA patients undergoing total knee arthroplasty. Macrophages isolated from these joint tissues were characterized via flow cytometry. Transcriptomic profiling of each macrophage subpopulations was performed using NanoString technology. Peripheral blood monocyte-derived macrophages (MDMs) were treated with synovial fluid and synovial tissue- and IPFP-conditioned media. Synovial fluid-treated MDMs were treated with platelet-rich plasma (PRP) and its effects on macrophage polarization were observed.

Results

Our findings show that CD11c+CD206+ macrophages were predominant in IPFPs and synovial tissues compared to other macrophage subpopulations (CD11c+CD206-, CD11c-CD206+, and CD11c-CD206- macrophages) of knee OA patients. The abundance of macrophages in IPFPs reflected those in synovial tissues but did not correlate with disease severity as determined from Mankin scoring of cartilage destruction. Our transcriptomics data demonstrated highly expressed genes that were related to OA pathogenesis in CD11c+CD206+ macrophages than CD11c+CD206-, CD11c-CD206+, and CD11c-CD206- macrophages. In addition, MDMs treated with synovial fluid, synovial tissue-conditioned media, or IPFP-conditioned media resulted in different polarization profiles of MDMs. IPFP-conditioned media induced increases in CD86+CD206+ MDMs, whereas synovial tissue-conditioned media induced increases in CD86+CD206- MDMs. Synovial fluid treatment (at 1:8 dilution) induced a very subtle polarization in each macrophage subpopulation. PRP was able to shift macrophage subpopulations and partially reverse the profiles of synovial fluid-treated MDMs.

Conclusion

Our study provides an insight on the phenotypes and genotypes of macrophages found in IPFPs and synovial tissues of knee OA patients. We also show that the microenvironment plays a role in driving macrophages to polarize differently and shifting macrophage profiles can be reversed by PRP.

Intraoperative landmark-based genicular nerve block versus periarticular infiltration for postoperative analgesia in total knee arthroplasty: a randomized non-inferiority trial

INTRODUCTION

Genicular nerve blocks (GNBs) are an emerging technique that have been used as a part of multimodal analgesia for total knee arthroplasty. The efficacy of intraoperative landmark-based GNBs, a recently introduced technique, has been established. We hypothesized that it would provide non-inferior postoperative analgesia compared with periarticular infiltration (PAI) when combined with continuous adductor canal block.

METHODS

This study randomized 140 patients undergoing total knee arthroplasty to receive either intraoperative landmark-based GNB (GNB group) or PAI (PAI group), with 139 completing the study. The primary outcomes were the pain scores at rest and during movement at 12 hours postoperatively on an 11-point Numerical Rating Scale; the non-inferiority margin was 1. Pain scores at additional time points, intravenous morphine consumption, time to first rescue analgesia, functional performance and muscle strength tests, and sleep disturbance were also assessed.

RESULTS

At 12 hours postoperatively, the PAI and GNB groups had median resting pain scores of 0 (0-2) and 0 (0-2), respectively. The median difference was 0 (95% CI -0.4 to 0.4, p=1), with the 95% CI upper limit below the prespecified non-inferiority margin. The median pain score during movement was 1.5 (0-2.3) and 2 (1-3.1) in the PAI and GNB groups, respectively. The median difference was 0.9 (95% CI 0.3 to 1.6, p=0.004), failing to demonstrate non-inferiority. The GNB group had higher intravenous morphine consumption at 12 hours postoperatively and a shorter time to first rescue analgesia.

CONCLUSIONS

GNB compared with PAI provides non-inferior resting pain relief. Non-inferiority was not established for pain during movement.

TRIAL REGISTRATION NUMBER

TCTR20220406001 (www.thaiclinicaltrials.org).

Comparison of Analgesic Efficacies of the iPACK (Interspace Between the Popliteal Artery and Capsule of the Posterior Knee) and Genicular Nerve Blocks Used in Combination With the Continuous Adductor Canal Block After Total Knee Arthroplasty: A Randomized Clinical Trial

BACKGROUND

The interspace between the popliteal artery and capsule of the posterior knee (iPACK) block and the genicular nerve block (GNB) are motor-sparing nerve blocks used for knee pain relief. We compared the analgesic efficacies of ultrasound-guided iPACK block and GNB when combined with continuous adductor canal block after total knee arthroplasty.

METHODS

In this randomized control study, 132 total knee arthroplasty patients were assigned to the iPACK, GNB, and iPACK + GNB groups. All patients received combined spinal anesthesia and continuous adductor canal block. The primary outcome was the 8-hour postoperative pain score during movement. Secondary outcomes were pain scores, posterior knee pain, intravenous morphine consumption, and tibial and common peroneal nerve sensorimotor function. All included patients completed the study.

RESULTS

The 4-hour and 8-hour postoperative pain scores during movement were significantly lower in the iPACK + GNB group than that in the iPACK group (-2.5 [3.6, 1.3]; P < .001 and -2 [-3, -1]; P < .001, respectively). The differences in rating pain scores and posterior knee pain were not clinically relevant. The iPACK group demonstrated a significantly higher intravenous morphine consumption than did the GNB and iPACK + GNB groups during the first 48 hours postoperatively (P < .001) but were not clinically relevant. There was no incidence of complete sensorimotor blockade in any of the groups.

CONCLUSION

The iPACK-GNB combination relieved pain during movement better than the iPACK block alone during the 8 hours postoperatively after total knee arthroplasty in setting of multimodal analgesia such as adductor canal block.

Effect of Adding Perineural Methylprednisolone to Peripheral Nerve Blocks Combined With Intravenous Dexamethasone for Prolonged Postdischarge Analgesia After Fast-track Total Knee Arthroplasty: A Randomized Controlled Trial

OBJECTIVES

Patients undergoing total knee arthroplasty (TKA) may experience moderate-to-severe subacute pain after hospital discharge that may be undermanaged. We aimed to evaluate the effect of methylprednisolone added to ultrasound-guided peripheral nerve blocks (PNBs) combined with multimodal analgesia including intravenous dexamethasone for prolonged analgesia after early discharge.

MATERIALS AND METHODS

We randomized 80 patients who underwent fast-track TKA into 2 groups. All patients received a periarticular injection, PNBs, and multiple doses of intravenous dexamethasone. The methylprednisolone group received 140 mg methylprednisolone in PNBs, while the nonmethylprednisolone group did not. The primary outcome was the incidence of moderate-to-severe pain (Numerical Rating Scale ≥4) during the first 12 postdischarge days. The secondary outcomes included pain scores until 3 postoperative months, incidence of rebound pain, functional performances, patient satisfaction, and adverse events.

RESULTS

No significant between-group differences were noted in the incidence of moderate-to-severe pain during the first 12 postdischarge days (nonmethylprednisolone vs. methylprednisolone groups: 70% vs. 69.2%, P=0.941). However, this incidence was significantly higher in the methylprednisolone group between 2 weeks and 1 month (P=0.015) and between 1 and 3 months (P=0.004) postoperatively. No between-group differences in the Numerical Rating Scale scores at the postdischarge time points, incidence of rebound pain, and functional performance results were noted.

DISCUSSION

Adding perineural methylprednisolone to ultrasound-guided PNBs for multimodal analgesia with intravenous dexamethasone did not prolong analgesia and improved the functional ability after fast-track TKA within 12 postdischarge days. However, the incidence moderate-to-severe pain may increase between the 2-week and 3-month follow-up.

Association between Common Variants in VEGFA Gene and the Susceptibility of Primary Knee Osteoarthritis

OBJECTIVES

This study aimed to analyze the relationship between vascular endothelial growth factor A (VEGFA) gene polymorphisms, plasma VEGFA, and the susceptibility of knee osteoarthritis (OA).

DESIGN

A total of 404 subjects, 202 knee OA subjects and 202 healthy volunteers, were enrolled into the study. Four distinct polymorphisms of the VEGFA gene were evaluated using polymerase chain reaction-restriction fragment length polymorphism: -2578C/A (rs699947), -1154G/A (rs1570360), -634C/G (rs2010963), and +936C/T (rs3025039). Plasma VEGFA levels were analyzed using enzyme-linked immunosorbent assay.

RESULTS

The most common nucleotides in both knee OA subjects and healthy controls were CC for -2578C/A, GG for -1154G/A, CG for -634C/G, and CC for +936C/T in the VEGFA gene. Genotype distribution and allele frequencies of VEGFA -2578C/A, -1154G/A, -634C/G, and +936C/T single nucleotide polymorphisms did not differ between OA patients and the controls. Plasma VEGFA levels showed no difference between OA patients and the controls. In contrast, plasma VEGFA levels of -634C/C genotype were significantly higher in OA patients than in the controls (P = 0.035). According to the -2578A/A genotype, patients with early stage OA had a higher odds ratio than those with advanced stage OA (P = 0.023).

CONCLUSIONS

VEGFA -2578C/A (rs699947), -1154G/A (rs1570360), -634C/G (rs2010963), and +936C/T (rs3025039) polymorphisms may not be responsible for OA susceptibility in the Thai population. However, the OA patients with A/A genotype at the -2578C/A seemed to have a lower potential risk of developing severe OA than those with the C/A and C/C genotypes. These findings would help elucidate and facilitate a better understanding of the genetic fundamentals of OA.

Knee joint line related to bony landmarks of the knee: a radiologic study in a Thai population

Background

During revision total knee arthroplasty (TKA), knee joint line restoration may be difficult due to bone loss or structural changes. Although bony landmarks are consistent and can be used as references, there are limited data in Asian patients. We studied the knee joint line related to bony landmarks of the knee in a Thai population.

Materials and methods

Magnetic resonance imaging (MRI) of 140 healthy knees of Thai patients (70 males, 70 females) were investigated. In all knees, a perpendicular line from knee joint line to the medial epicondyle (distance A) and the lateral epicondyle (distance B) in the coronal plane were measured. In the sagittal plane, a perpendicular line from the knee joint line to the fibular head (distance C), the tibial tubercle (distance D), and the inferior patellar pole (distance E) were measured. The femoral transepicondylar width (FW) was measured along the transepicondylar axis. The ratios of distances A, B, C, D, and E related to FW were evaluated (epicondylar ratio).

Results

The mean and standard deviation (SD) of distances A, B, C, D, E, and FW were 27.1 ± 2.7 mm, 21.7 ± 2.5 mm, 12.6 ± 3 mm, 21.3 ± 3.6 mm, 7.6 ± 4.8 mm, and 76.7 ± 3.99, respectively. There was wide variation of measured values, with statistically significant differences between genders in distances A, B, C, and FW. The mean and SD of epicondylar ratios A/FW, B/FW, C/FW, D/FW, and E/FW were 0.35 ± 0.02, 0.29 ± 0.02, 0.16 ± 0.05, 0.28 ± 0.04, and 0.09 ± 0.04, respectively. All epicondylar ratios demonstrated less variation than all measured distances, with statistical differences between genders in the A/FW and D/FW ratios. However, the B/FW ratio had the highest consistent mean value. In addition, it had narrower SD than the rest (0.29 ± 0.02; range, 0.22–0.33).

Conclusions

In Thai knees, the measured distances from bony landmarks to the knee joint line had higher variation than the epicondylar ratio. Among all studied epicondylar ratios, the ratio between lateral epicondyle to joint line distance (distance B)/FW demonstrated the narrowest range of mean and SD values; therefore, this could be the most reliable landmark for intraoperative knee joint line verification by multiplying the FW of the patient by 0.29 to get distance B in that patient.

Does the intramedullary femoral canal plug reduce blood loss during total knee arthroplasty?

Introduction

The benefit of the femoral canal bone plug during total knee arthroplasty (TKA) in reducing blood loss has never been proven. The aim of this meta-analysis was to determine whether the femoral canal bone plug significantly reduces blood loss in primary TKA.

Method

All studies published before December 2021 were searched. The inclusion criteria were randomized controlled trials comparing blood loss between TKA with plugged and unplugged femoral intramedullary canal, respectively. The primary outcome was postoperative hemoglobin reduction.

Results

Five studies with a total of 717 patients (361 in the plugged group, 356 in the unplugged group) met the criteria for inclusion in the meta-analysis. The mean difference in hemoglobin level between the two groups was 0.92 g/dL, with significantly less hemoglobin reduction in the plugged group (95% confidence interval [CI] − 1.64 to − 0.21, p = 0.01). The patients in the plugged group also had a significantly lower risk of receiving a blood transfusion (risk ratio 0.58, 95% CI 0.47–0.73, p < 0.00001).

Conclusions

This meta-analysis demonstrates that using a femoral canal bone plug can significantly reduce blood loss and lower the risk ratio of blood transfusion in patients undergoing TKA.

Cytokine Profiling and Intra-Articular Injection of Autologous Platelet-Rich Plasma in Knee Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease leading to joint pain and stiffness. Due to lack of effective treatments, physical and psychological disabilities caused by OA have a detrimental impact on the patient’s quality of life. Emerging evidence suggests that intra-articular injection of platelet-rich plasma (PRP) may provide favorable results since PRP comprises not only a high level of platelets but also a huge amount of cytokines, chemokines, and growth factors. However, the precise mechanism and standardization method remain uncertain. This study aimed to examine cytokine profiling in both PRP and platelet-poor plasma (PPP) of knee OA patients and to determine the effects of PRP on OA chondrocytes and knee OA patients. PRP contained a wide variety of cytokines, chemokines, growth factors, and autologous intra-articular PRP injection resulted in favorable outcomes in knee OA patients. Significant increases in levels of IL-1, IL-2, IL-7, IL-8, IL-9, IL-12, TNF-α, IL-17, PDGF-BB, bFGF, and MIP-1β were detected in PRP compared to PPP (p < 0.001). An in vitro study showed a marked increase in proliferation in OA chondrocytes cultured with PRP, compared to PPP and fetal bovine serum (p < 0.001). In a clinical study, knee OA patients treated with PRP showed improvement of physical function and pain, assessed by physical performance, Western Ontario and McMaster Universities Arthritis Index and visual analog scale. Our findings from both in vitro and clinical studies suggest that intra-articular PRP injection in knee OA patients may be a potential therapeutic strategy for alleviating knee pain and delaying the need for surgery.

Two or four injections of platelet-rich plasma for osteoarthritic knee did not change synovial biomarkers but similarly improved clinical outcomes

We compared two and four intra-articular injections of platelet-rich plasma (PRP) in terms of changes of synovial cytokines and clinical outcomes. One hundred twenty-five patients having knee osteoarthritis (OA) underwent PRP injections at a 6-week interval. Before each PRP injection, synovial fluid aspiration was collected for investigation. Patients were divided into two or four intra-articular PRP injections (group A and B, respectively). Changes in synovial biomarkers were compared with the baseline levels of both groups, and clinical outcomes were evaluated until one year. Ninety-four patients who had completed synovial fluid collection were included for final evaluation, 51 in group A and 43 in group B. There were no differences in mean age, gender, body mass index (BMI), and radiographic OA grading. The average platelet count and white blood cell count in PRP were 430,000/µL and 200/ µL, respectively. There were no changes of synovial inflammatory cytokines (IL-1β, IL-6, IA-17A, and TNF-alpha), anti-inflammatory cytokines (IL-4, IL-10, IL-13, and IL-1RA), and growth factors (TGF-B1, VEGF, PDGF-AA, and PDGF-BB) between baseline levels and six weeks in group A, and 18 weeks in group B. Both groups had significantly improved clinical outcomes from six weeks including visual analog scale (VAS), patient-reported outcome measures [PROMs; Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Short Form-12 (SF-12)], with a significant delayed improvement of performance-based measures [PBMs; time up and go (TUG), 5-time sit to stand test (5 × SST), and 3-min walk test (3-min WT)]. In conclusion, two- or four-PRP intra-articular injection at a 6-week interval for knee OA demonstrated no changes of synovial cytokines and growth factors but similarly improved clinical outcomes from 6 weeks until 1 year.

Effect of ultrasound-guided selective sensory nerve blockade of the knee on pain management compared with periarticular injection for patients undergoing total knee arthroplasty: A prospective randomized controlled trial

BACKGROUND

Ultrasound-guided selective sensory nerve blockade (SSNB) of the knee, including an adductor canal block (ACB), anterior femoral cutaneous nerve block, and infiltration between the popliteal artery and posterior capsule of the knee may provide effective motor-sparing knee analgesia for total knee arthroplasty (TKA). We hypothesized that the SSNB would manage pain better on ambulation 24 hours postoperatively compared to periarticular infiltration (PAI), when combined with postoperative continuous ACB.

METHODS

Seventy-two patients undergoing elective TKA under spinal anesthesia were randomly assigned to either SSNB (SSNB group) or intraoperative PAI (PAI group). All patients received postoperative multimodal analgesia, including continuous ACB. The primary outcome was pain on ambulation 24 hours postoperatively. Secondary outcomes included rest and dynamic numerical rating scale pain score, intravenous morphine requirement, functional performance measures, adverse events, satisfaction, and length of stay.

RESULTS

There was no difference in pain score during movement between the groups (mean difference -0.48 [-1.38 to 0.42], p = 0.3) and other immediate overall pain scores 24 hours postoperatively. Patients in the SSNB group had significantly lower intravenous morphine requirement than the PAI group for 48 hours postoperatively (0 [0, 0] vs. 0 [0, 2]; p = 0.008). There was no intergroup difference in the performance-based measures, satisfaction, and length of stay.

CONCLUSIONS

The SSNB did not provide superior postoperative analgesia, or improvement in immediate functional performance. However, it may result in lower opioid consumption postoperatively when compared with the intraoperative PAI.

Plasma and Joint Fluid Glypican-3 Are Inversely Correlated with the Severity of Knee Osteoarthritis

OBJECTIVE

Glypican-3 possesses a possible action in regulation of bone growth and development implicated in osteoarthritis (OA) pathology. Therefore, this study aimed to investigate glypican-3 in plasma and synovial fluid of knee OA patients and to determine the possible association between glypican-3 levels and radiographic severity.

DESIGN

A total of 80 knee OA patients and 80 healthy controls were recruited. Glypican-3 levels in plasma and synovial fluid were measured using enzyme-linked immunosorbent assay. The severity of knee OA was assessed by radiographic grading according to the Kellgren-Lawrence classification. Relative mRNA expression of glypican-3 in 10 inflamed synovial tissues from OA patients and 10 noninflamed synovial controls was quantified using real-time polymerase chain reaction.

RESULTS

Plasma glypican-3 levels were significantly lower in OA patients than in healthy controls (P = 0.03), whereas synovial fluid glypican-3 levels were remarkably greater than in paired plasma samples of OA patients (P < 0.001). Subsequent analysis demonstrated that plasma and synovial fluid glypican-3 levels were inversely associated with the radiographic severity of knee OA (r = -0.691, P < 0.001; r = -0.646, P < 0.001, respectively). Furthermore, there was a positive relationship between plasma and synovial fluid glypican-3 levels in knee OA patients (r = 0.515, P < 0.001). Additionally, overexpression of glypican-3 mRNA was observed in inflamed synovium of OA patients (P = 0.021).

CONCLUSIONS

The present study revealed that plasma and synovial glypican-3 levels were negatively associated with radiographic severity of knee OA. Glypican-3 could emerge as a potential biomarker for reflecting the severity of knee OA and might play a plausible role in the pathophysiology of degenerative joint disease.

The analgesic efficacy of anterior femoral cutaneous nerve block in combination with femoral triangle block in total knee arthroplasty: a randomized control trial

Background

Ultrasound-guided femoral triangle block (FTB) can provide motor-sparing anterior knee analgesia. However, it may not completely anesthetize the anterior femoral cutaneous nerve (AFCN). We hypothesized that an AFCN block (AFCNB) in combination with a FTB would decrease pain during movement in the immediate 12-hour postoperative compared with a FTB alone.

Methods

Eighty patients scheduled to undergo total knee arthroplasty (TKA) were randomized to receive either FTB alone (FTB group) or AFCNB with FTB (AFCNB + FTB group) as a part of the multimodal analgesic regimen. The primary outcome was pain during movement 12 hours postoperatively. Secondary outcomes included numeric rating scale (NRS) pain scores, incidence of surgical incision site pain, intravenous morphine consumption, immediate functional performance, patient satisfaction, and length of hospital stay.

Results

The NRS pain scores on movement 12 hours postoperatively were significantly lower in patients of AFCNB + FTB group compared to those in patients of FTB group (mean difference, -2.02 [95% confidence interval: -3.14, -0.89], P < 0.001). Incidence of pain at the site of surgical incision in 24 hours postoperatively and morphine consumption in 48 hours postoperatively were significantly lower (P < 0.001) and quadriceps muscle strength at 0 degree immediately after the surgery was significantly greater in patients of AFCNB + FTB group (P = 0.04).

Conclusions

The addition of ultrasound-guided AFCNB to FTB provided more effective analgesia and decreased opioid requirement compared to FTB alone after TKA and may enhance immediate functional performance on the day of surgery.

The infrapatellar fat pad produces interleukin-6-secreting T cells in response to a proteoglycan aggrecan peptide and provides dominant soluble mediators different from that present in synovial fluid

OBJECTIVE

The purpose of this study was to investigate the effects of osteoarthritis (OA) peripheral blood mononuclear cell (PBMC) -stimulating proteoglycan aggrecan peptides on T cells present in infrapatellar fat pads (IPFPs) and synovial tissues, and to correlate these findings with mediators present in synovial fluid of OA patients.

METHODS

We tested for interleukin-6 (IL-6) -producing T cells in IPFPs of patients with knee OA using ELISPOT. Cytokine and cytotoxic mediator production from OA PBMCs, IPFPs, synovial tissues, and synovial fluids in response to proteoglycan aggrecan peptides were quantified by cytometric bead array. Patterns of cytokine and cytotoxic mediator production were analyzed and compared.

RESULTS

T cells from IPFPs elicited strong responses towards the p263-280 peptide by secreting IL-6. In addition, there was a trend that the p263-280 peptide stimulated higher production of cytokines/cytotoxic mediators than other proteoglycan aggrecan peptides, although this was not statistically significant. In patients with knee OA, a group of cytotoxic mediators (sFas, perforin, granzyme A, and granulysin) and IL-6 were detectable at high levels from the synovial fluid. In addition, inflammation in patients with knee OA was more pronounced in joint-surrounding tissues than levels in circulating peripheral blood.

CONCLUSION

Our data suggest that T cells responding to the p263-280 peptide contribute to the secretion of various soluble mediators that are found within the synovial fluid. We also identified potential new candidates that may serve as biomarkers of knee OA.

Adductor Canal Block Combined With iPACK (Interspace Between the Popliteal Artery and the Capsule of the Posterior Knee) Block vs Periarticular Injection for Analgesia After Total Knee Arthroplasty: A Randomized Noninferiority Trial

BACKGROUND

The combination of adductor canal block (ACB) and infiltration between the popliteal artery and the posterior capsule of the knee (iPACK) block may provide sufficient motor-sparing anterior and posterior knee analgesia after total knee arthroplasty. This study aimed to determine if ACB with iPACK block was noninferior to ACB with periarticular injection (PAI) when combined with postoperative multimodal analgesia regimen.

METHODS

Seventy-six patients were randomized to receive either ACB + iPACK block and continuous ACB (CACB) (ACB + iPACK group) or PAI and CACB (ACB + PAI group). Noninferiority was concluded for the primary outcome if the adjusted mean between-group difference in pain on movement at 12 postoperative hours was within 1.3 points on a visual analog pain scale. Pain scores, morphine consumption, functional performance, and adverse events were the secondary outcome measures assessed for superiority.

RESULTS

Adjusted mean differences, (ACB + iPACK) - (ACB + PAI), in anterior and posterior knee pain scores on movement at 12 postoperative hours were -0.66 (-1.86, 0.54) and -0.19 (-1.36, 0.99), respectively. The upper limit of 95% confident interval was lower than the prespecified noninferiority limit. The mean visual analog scale pain scores were low and no clinically significant differences between groups. However, morphine requirement at 48 postoperative hours was significantly higher (P < .05) and showed greater reduced quadriceps strength at 0 and 45 degrees on postoperative day 0 (P = .006 and .04, respectively) in the ACB + iPACK group.

CONCLUSIONS

ACB with iPACK block provides a noninferior analgesia compared with PAI when combined with CACB. However, patients who received ACB + iPACK block may require higher amounts of opioids and have worse immediate functional performance.

LEVEL OF EVIDENCE

Therapeutic level I.

Analgesic efficacy of infiltration between the popliteal artery and capsule of the knee (iPACK) block added to local infiltration analgesia and continuous adductor canal block after total knee arthroplasty: a randomized clinical trial

Background

A combination of motor-sparing analgesia with local infiltration analgesia (LIA) and continuous adductor canal block (CACB) may improve postoperative pain and functional recovery for total knee arthroplasty (TKA). We hypothesized that the addition of a novel technique for posterior knee block, known as the infiltration between the popliteal artery and capsule of the knee (iPACK) block, to LIA with CACB would reduce opioid requirements.

Methods

In this double-blinded randomized controlled trial, 72 patients were assigned to receive either LIA with CACB (LIA+CACB group) or iPACK block with LIA and CACB (iPACK+LIA+CACB group). The primary outcome was cumulative postoperative intravenous morphine consumption within 24 hours. The secondary outcomes included numerical rating scale pain scores, incidence of posterior knee pain, performance test results, patient satisfaction, length of stay, and adverse events.

Results

Morphine consumption within 24 hours postoperatively showed no significant intergroup difference (LIA+CACB; 1.31±1.85 mg vs iPACK+LIA+CACB; 0.61±1.25 mg, p=0.08). There were no clinically significant differences in the overall pain scores between the groups. The lower Timed Up and Go test scores on postoperative days 1 and 2, along with a shorter duration of hospitalization, were found in the iPACK+LIA+CACB group (p<0.05).

Conclusion

The addition of an iPACK block to the LIA and CACB does not reduce the postoperative opioid consumption nor improve analgesia. However, it may improve immediate functional performance and reduce the length of hospitalization after TKA.

Trial registration number

TCTR20180702001.

Circulating and Synovial Fluid Heat Shock Protein 70 Are Correlated with Severity in Knee Osteoarthritis

OBJECTIVE

Heat shock proteins are molecules rapidly produced under conditions of environmental stress, and involve in protecting the cells structural integrity and function. Osteoarthritis (OA) is a chronic destructive disorder of the joints manifested by the ongoing deterioration and loss of articular cartilage. The present study aimed to analyze circulating and synovial heat shock protein (Hsp70) values in knee osteoarthritis patients and healthy controls and to determine their relationship with the radiographic grading of the severity of knee OA.

DESIGN

Seventy-two subjects with knee OA and 30 control participants were recruited. Circulating and joint fluid Hsp70 values were quantified by commercially available enzyme-linked immunosorbent assay.

RESULTS

Circulating Hsp70 was markedly higher in knee OA patients compared with that of healthy volunteers (P = 0.01). Correspondingly, synovial fluid Hsp70 was 3-fold greater than paired circulating Hsp70 samples (P < 0.001). Further analysis revealed that circulating and joint fluid Hsp70 values were significantly related with the radiographic severity of knee OA (r = 0.413, P < 0.001 and r = 0.658, P < 0.001, respectively). Subsequently, circulating Hsp70 value was directly associated with joint fluid Hsp70 value (r = 0.704, P < 0.001).

CONCLUSIONS

Circulating and synovial Hsp70 levels were positively correlated with the radiographic severity of knee OA. Hsp70 could represent a potential biochemical marker for predicting the severity and may play a fundamental part in the pathogenic mechanism of knee OA.

Motor-sparing effect of iPACK (interspace between the popliteal artery and capsule of the posterior knee) block versus tibial nerve block after total knee arthroplasty: a randomized controlled trial

Background and objective

An ultrasound-guided anesthetic technique targeting the interspace between the popliteal artery and capsule of the posterior knee (iPACK) can provide posterior knee analgesia with preserved motor function after total knee arthroplasty (TKA). This study compared the peroneal nerve motor-sparing effects of iPACK block and tibial nerve block (TNB) when combined with local infiltration analgesia (LIA) and continuous adductor canal block (CACB).

Methods

In this study, 105 patients scheduled for elective TKA were randomized to receive proximal iPACK block (iPACK1), distal iPACK block (iPACK2), or TNB, along with spinal anesthesia, modified LIA, and CACB. The primary outcome was the incidence of common peroneal nerve (CPN) motor blockade. Secondary outcomes included CPN sensory function, tibial sensorimotor function, posterior knee pain, pain score, intravenous morphine requirement, timed up-and-go test, quadriceps muscle strength, range of motion, length of hospital stay, patient satisfaction, and adverse events.

Results

The incidence of CPN motor blockade was significantly higher in the TNB group than in the iPACK1 (p=0.001) and iPACK2 (p=0.001) groups, but was not significant between the iPACK1 and iPACK2 groups (p=0.76). Tibial nerve motor function was more preserved in the iPACK1 and iPACK2 groups than in the TNB group (p<0.001 and p<0.001, respectively). Complete CPN and tibial sensorimotor blockade were not observed in the iPACK2 group. Posterior knee pain score was significantly higher in the iPACK1 group than in other groups during the 24-hour postoperative period (p=0.001).

Conclusions

Compared with TNB, iPACK1 and iPACK2 preserved CPN and tibial nerve motor function to a greater extent. However, iPACK2 did not demonstrate complete CPN and tibial nerve motor blockade while maintaining effective posterior knee pain relief.

Trial registration number

TCTR20180206002.

Relationships between blood leukocyte mitochondrial DNA copy number and inflammatory cytokines in knee osteoarthritis

Osteoarthritis (OA) is a degenerative articular disorder manifested by cartilage destruction, subchondral sclerosis, osteophytes, and synovitis, resulting in chronic joint pain and physical disability in the elderly. The purpose of this study was to investigate mitochondrial DNA copy number (mtDNA_CN) and inflammatory cytokines in primary knee OA patients and healthy volunteers. A total of 204 knee OA patients and 169 age-matched healthy volunteers were recruited. Their relative blood leukocyte mtDNA_CN was assessed by quantitative real-time polymerase chain reaction (qRT-PCR), and ten inflammatory cytokines in their plasma were detected by multiplex immunoassay. Blood leukocyte mtDNA_CN in the OA group was significantly lower than that in the control group. Leukocyte mtDNA_CN in the control group was negatively correlated with their age (r=-0.380, P<0.0001), whereas mtDNA_CN in the OA group was positively correlated with their age (r=0.198, P<0.001). Plasma interleukin-4 (IL-4) and IL-6 were significantly higher in the knee OA group than in the control group. The plasma IL-6 level was positively correlated with blood leukocyte mtDNA_CN in the OA group (r=0.547, P=0.0014). IL-5 showed as a major factor (coefficient 0.69) in the second dimension of principle components analysis (PCA)-transformed data and was significantly higher in the OA group (P<0.001) as well as negatively correlated with mtDNA_CN (r=-0.577, P<0.001). These findings suggest that elevation of plasma IL-4 and IL-6 and a relative reduction in mtDNA_CN might be effective biomarkers for knee OA. IL-5 is a plausible factor responsible for decreasing blood leukocyte mtDNA_CN in knee OA patients.

Blood leukocyte LINE-1 hypomethylation and oxidative stress in knee osteoarthritis

Aim

Joints inflammation is one of the most pathologic processes leading to the development of osteoarthritis (OA), possibly leading to genomic instability. LINE-1 is transposable elements, and alterations in LINE-1 methylation induced by 8-hydroxy-2′-deoxyguanosine (8-OHdG) can cause genomic instability contributing to OA development. Herein, the present study examined associations between LINE-1 methylation, 8-OHdG, and knee OA severity.

Methods

LINE-1 methylation levels were measured in 104 knee OA patients and 96 healthy controls by quantitative combined bisulfite restriction analysis. 8–OHdG was investigated by ELISA. The knee OA severity was appraised by questionnaires (VAS, WOMAC, KOOS, and lequesne index) and radiological severity based on the grading of Kellgren and Lawrence (KL) standard criteria.

Key findings

Blood leukocyte LINE-1 methylation levels were significantly lower in knee OA patients than in healthy controls. Interestingly, individuals with LINE-1 hypomethylation were significantly associated with an elevated risk of knee OA. Linear regression analysis revealed that LINE-1 methylation was independently associated with KL grading of knee OA. Furthermore, plasma 8–OHdG levels in OA cases were not significantly different from those in healthy volunteers, whereas synovial fluid 8–OHdG values were considerably higher than in paired plasma specimens of the OA subjects.

Significance

This study demonstrated that LINE-1 hypomethylation in blood leukocytes was associated with increased risk and radiographic severity of knee OA, and increased synovial fluid 8–OHdG levels were observed in knee OA patients. Collectively, LINE-1 hypomethylation and elevated 8–OHdG could emerge as biomarkers indicating the severity of knee OA and may take a possible part in the pathological process of knee OA.

Optimal location of local anesthetic injection in the interspace between the popliteal artery and posterior capsule of the knee (iPACK) for posterior knee pain after total knee arthroplasty: an anatomical and clinical study

Background

This study aimed to determine the optimal location of local anesthetic injection in the interspace between the popliteal artery and posterior capsule of the knee (iPACK), using the anatomical pattern of the articular branch of tibial nerve (ABTN). We hypothesized that injection at the level of ABTN forming a popliteal plexus would mainly spread throughout the popliteal fossa without contacting the tibial or peroneal nerves.

Methods

The anatomical study included 30 soft cadavers. Ultrasound-guided dye injection was performed in legs of 10 cadavers after identifying the position of the ABTN and surrounding structures, followed by dissection to assess its spread. Clinical study was conducted in 15 patients undergoing total knee arthroplasty (TKA) with ultrasound-guided injection in the iPACK. All patients also received continuous adductor canal block. Sensorimotor function of the tibial and common peroneal nerves was determined.

Results

In the distal portion of the popliteal fossa, the tibial nerve and popliteal vessels ran superficially and closely together. The trajectory of ABTN ran lateral to the popliteal vasculature, forming a plexus towards the posterior capsule of the knee below the medial side of the upper edge of lateral femoral condyle. In cadavers, the ABTN and surrounding area of the popliteal plexus were stained with dye after injection. In the clinical study, no patients experienced complete motor or sensory blocks.

Conclusions

We described a modified iPACK technique injection at the level of the ABTN forming the popliteal plexus, and it may constitute an optional anesthetic regimen to promote early ambulation following TKA.

Opioid-Sparing Analgesia and Enhanced Recovery After Total Knee Arthroplasty Using Combined Triple Nerve Blocks With Local Infiltration Analgesia

BACKGROUND

Peripheral nerve block and local infiltration analgesia (LIA) have an increasing role as part of multimodal analgesia for enhanced recovery after total knee arthroplasty (TKA). We hypothesized that the combination of obturator nerve block (ONB) and tibial nerve block (TNB) would reduce pain and opioid consumption more than ONB or TNB alone when combined with continuous adductor canal block and LIA.

METHODS

Ninety patients were recruited into the study and received spinal anesthesia, LIA, and continuous adductor canal block. They were further randomized to receive either an ONB (group 1), a TNB (group 2), or both (group 3). The primary outcome was total morphine consumption over the postoperative 24 hours. The secondary outcomes included visual analog scale scores, time to first and total dosage of rescue analgesia, Timed Up and Go test, range of motion, muscle strength test, hospital stay, and patient satisfaction.

RESULTS

Eighty-nine patients completed analysis. The median total morphine consumption during the first 24 postoperative hours was 2 mg (interquartile range [IQR] 0-4) in group 3, 4 mg (IQR 2-8) in group 2, and 6 mg (IQR 6-14) in group 1 (P < .001). Posterior knee pain during the first 24 hours postoperatively was significantly lower in group 3 than in group 1 (P = .006). The ability to ambulate and quadriceps strength were significantly better in group 3 than in the other groups.

CONCLUSION

The combination of triple nerve block was superior to double nerve block in improving analgesia and functional outcomes in the immediate postoperative period after total knee arthroplasty, when combined with LIA.

Functional and T Cell Receptor Repertoire Analyses of Peripheral Blood and Infrapatellar Fat Pad T Cells in Knee Osteoarthritis

Objective.

Osteoarthritis (OA) is a condition that features inflammation and immune responses of innate and adaptive immunity. The role of T cells in knee OA pathogenesis is still unclear. Our aim was to characterize T cell functions and their clonality in patients with knee OA in peripheral blood (PB) and infrapatellar fat pads (IPFP).

Methods.

We isolated T cells from PB and IPFP of patients with knee OA and PB of healthy individuals and determined soluble mediators produced from these cells. In addition, we performed a clonal analysis of activated CD8+ T cells and compared the T cell receptor β-variable gene chain (TRBV) usages between T cells in PB and IPFP of patients with knee OA.

Results.

Our results suggest that in patients with knee OA, circulating T cells possess a more “cytotoxic” profile or rather impaired cytokine production, but the knee microenvironment allows for these T cells to produce proinflammatory cytokines [interleukin (IL)-1β, IL-6, tumor necrosis factor], IL-17, and interferon-γ within IPFP. Activated CD8+ IPFP T cells carry different repertoire distribution from those present in PB of patients with knee OA. Shared TRBV usage of activated CD8+ IPFP T cells among the 3 patients with knee OA was also observed.

Conclusion.

Our study describes the nature of T cells in knee OA that may be due to “unhealthy” aging or other factors that drive healthy aging T cells into a state of imbalance, thus contributing to the pathogenesis of knee OA.

Does Adductor Canal Block Have a Synergistic Effect with Local Infiltration Analgesia for Enhancing Ambulation and Improving Analgesia after Total Knee Arthroplasty?

Purpose

We compared a single-injection adductor canal block (ACB) with or without local infiltration analgesia (LIA) for accelerating functional recovery and reducing postoperative pain after total knee arthroplasty (TKA).

Materials and Methods

Sixty-two patients undergoing TKA with simple spinal analgesia and ACB were randomized to receive either LIA (group A+L) or placebo LIA (group A). Postoperative visual analog scale (VAS) score for pain, Timed Up and Go (TUG) test and quadriceps strength, total dosage of rescue analgesia, time to first rescue analgesia, and adverse events were serially evaluated from postoperative day 1 to 3 months.

Results

There were no differences between both groups in pre- and postoperative VAS, TUG test, quadriceps strength 2 days, 3 days, 2 weeks, 6 weeks, and 3 months postoperatively. There were no differences in Knee Society clinical and function scores at 6 months and 1 year. However, group A+L had a significantly longer time for postoperative rescue analgesia (491 minutes vs. 143 minutes, p=0.04) with less patients requiring rescue analgesia during 6 hours after surgery (16.7% vs. 43.3%, p=0.024). Both groups had similarly high rates of patient satisfaction with low adverse event rates.

Conclusions

Combined ACB and LIA in TKA enhanced early ambulation with reduced and delayed rescue analgesia.

Comparison of Adductor Canal Block Versus Local Infiltration Analgesia on Postoperative Pain and Functional Outcome after Total Knee Arthroplasty: A Randomized Controlled Trial

Introduction: Total knee arthroplasty (TKA) is associated with intense postoperative pain for which effective analgesia is essential to facilitate early postoperative recovery. Adductor canal block (ACB) and local infiltration analgesia (LIA) have become increasingly involved in postoperative pain management after TKA. We aimed to compare their efficacy and outcomes in patients undergoing TKA.

Materials and Methods: Sixty patients undergoing unilateral TKA were randomized to receive either postoperative single-injection ACB (Group A) or LIA (Group L) during the operation. All patients received spinal anaesthesia. Primary outcome was total morphine consumption over postoperative 24 hours. Visual analog pain scale, time to first and total dosage of rescue analgesia, performance-based evaluations [timed-up and go (TUG) test, quadriceps strength], side-effects, length of hospital stay and patient satisfaction were measured.

Results: Fifty-seven patients were available for analysis. Median total morphine consumption over 24 and 48 postoperative hours of Group A were significantly less than Group L (6/10 mg vs 13/25 mg, p, 0.008 and 0.001, respectively). Similarly, Group A had significantly lower VAS at postoperative 6, 12 and 18 hours, VAS at ambulation on postoperative (POD) 1-3, better TUG tests on POD 2 and during POD 3 than those of Group L. However, quadriceps strength and patient satisfaction were not different between both groups.

Conclusion: Patients undergoing TKA with single-injection ACB required less postoperative opioids than those with LIA. Furthermore, multimodal analgesia using ACB provided better postoperative analgesia, as well as performance-based activities, than those with LIA.

Vitamin D Supplementation Improves Quality of Life and Physical Performance in Osteoarthritis Patients

(1) Background: Lower levels of serum 25-hydroxyvitamin D (25(OH)D) are common in osteoarthritis (OA) patients. However, the effect of vitamin D supplementation on muscle strength and physical performance remains unclear. This study will investigate the effects of vitamin D₂ supplementation on muscle strength and physical performance in knee OA patients; (2) Methods: One hundred and seventy-five primary knee OA patients with low levels of serum 25(OH)D (<30 ng/mL) received 40,000 IU vitamin D₂ (ergocalciferol) per week for six months. Body composition, muscle strength, physical performance, serum 25(OH)D level, leptin, interlukin-6 (IL-6), parathyroid hormone (PTH), protein carbonyl, and metabolic profile were analyzed; (3) Results: Baseline mean serum 25(OH)D levels in knee OA patients was 20.73 ng/mL. Regarding baseline vitamin D status, 58.90% of patients had vitamin D insufficiency, and 41.10% had vitamin D deficiency. After vitamin D₂ supplementation for six months, mean serum 25(OH)D level was 32.14 ng/mL. For post-supplementation vitamin D status, 57.10% of patients had vitamin D sufficiency and 42.90% had vitamin D insufficiency. From baseline to six months, there was a significant increase in mean serum 25(OH)D level (p < 0.001), while mean LDL cholesterol (p = 0.001), protein carbonyl (p = 0.04), and PTH (p = 0.005) all significantly decreased. Patient quality of life (SF-12) and pain (visual analog scale, VAS) both improved significantly from baseline to the six-month time point (p = 0.005 and p = 0.002, respectively). Knee OA patients demonstrated significant improvement grip strength and physical performance measurements after vitamin D₂ supplementation (p < 0.05); (4) Conclusions: Vitamin D₂ supplementation for six months reduced oxidative protein damage, decreased pain (VAS), improved quality of life, and improved grip strength and physical performance in osteoarthritis patients.

Effect of vitamin E on oxidative stress level in blood, synovial fluid, and synovial tissue in severe knee osteoarthritis: a randomized controlled study

Background

This study was performed to evaluate the antioxidative and anti-inflammatory effects of vitamin E on oxidative stress in the plasma, synovial fluid, and synovial tissue of patients with knee osteoarthritis.

Methods

Seventy-two patients with late-stage knee osteoarthritis scheduled for total knee arthroplasty were randomized to take oral placebo (Group A) or 400 IU of vitamin E (Group B) once a day for 2 months before undergoing surgery. The blood levels of endpoints indicating oxidative stress or antioxidant capacity, Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index score (WOMAC), and adverse effects were compared before and after the intervention between the two groups. At surgery, these redox endpoints and histological findings were compared between the synovial fluid and synovial tissue.

Results

In blood samples, the pre-intervention of oxidative stress and antioxidative capacity were not different between Group A and Group B. In post-intervention blood samples, the Malondialdehyde (Group A 1.34 ± 0.10, Group B 1.00 ± 0.09, p < 0.02), Alpha tocopherol (Group A 15.92 ± 1.08, Group B 24.65 ± 1.47, p < 0.01) and Trolox equivalent antioxidant capacity (Group A 4.22 ± 0.10, Group B 5.04 ± 0.10, 0 < 0.01) were significantly different between Group A and Group B. In synovial fluid samples, the Malondialdehyde (Group A 1.42 ± 0.12, Group B 1.06 ± 1.08, p 0.01), Alphatocopherol (Group A 4.51, Group B 7.03, p < 0.01), Trolox equivalent antioxidant capacity (Group A, 1.89 ± 0.06, Group B 2.19 ± 0.10) were significantly different between Group A and Group B. The pre-intervention WOMAC score and KSS score were not different between Group A and Group B. The post-intervention WOMAC score was significantly improved in all categories in Group B (Pain: Group A 27.26 ± 0.89, Group B 19.19 ± 1.43, p < 0.01; Stiffness: Group A 8.23 ± 0.79, Group B 5.45 ± 0.73, p 0.01; Function: Group A 94.77 ± 4.22, Group B 72.74 ± 6.55, p < 0.01). The post-intervention KSS score was significantly improved in all categories in Group B (Clinical: Group A 25.31 ± 14.33, Group B 33.52 ± 16.96, p < 0.01; Functional: Group A 41.43 ± 16.11, Group B 51.61 ± 19.60, p 0.02). Significantly fewer synovial tissue cells were stained with nitrotyrosine and hematoxylin–eosin in Group B than in Group A. There were no differences in adverse effects or surgical complications between the groups.

Conclusion

Vitamin E is an effective antioxidant that can improve clinical symptoms and reduce oxidative stress conditions in patients with late-stage knee osteoarthritis.

Trial registration

This research project had been approved for registration at Thai Clinical Trials Registry (TCTR) since 2016–08-28 11:26:32 (Retrospective registered). The TCTR identification number is TCTR20160828001.

Clinical report. Atypical acetabular bone loss in chronic septic total hip arthroplasty loosening

Background: When a periprosthetic infection is diagnosed, the surgical treatment is usually performed as soon as possible to avoid further bone damage or life threatening complications. There is no report on the radiographic change in patients with untreated infected total hip arthroplasty (THA) for several years.

Objective: Report radiographic change in patients with untreated infected THA.

Method: Two patients presented with chronic septic loosening of cemented acetabular fixation after total hip replacement at King Chulalongkorn Memorial Hospital. Both patients had mild hip pain and had been lost for follow-up until the bone destruction became very severe. Serial radiographs after the surgeries were evaluated. The Paprosky’s acetabular bone loss classification was used to classify the radiographic findings.

Results: Based on the Paprosky’s classification for acetabular bone loss, there were two similar atypical radiographic findings found in both patients. These included pelvic discontinuity from extensive medial acetabular bone loss beyond the Kohler’s line, and minimal superior and inferior acetabular bone loss.

Conclusion: These atypical radiographic findings were rarely observed in septic acetabular loosening patients, as infection usually causes patients to present earlier. Following the septic acetabular loosening of THA, surgical procedure should be performed before massive bone damage was demonstrated.

Spontaneous acetabular periprosthetic fracture in a patient continuously having zoledronic acid

Zoledronic acid has been used for prevention of osteolytic and osteoblastic bone metastasis. This case report illustrates an undesirable consequence from prolonged usage of zoledronic acid in bone metastasis prevention. Periprosthetic acetabular fracture in a patient treated with zoledronic acid for 7 years was reported. The clinical presentation, radiographic and pathological results were described. This is a rare complication after total hip arthroplasty which should not be ignored especially in patients who received long term bisphosphonate.

Accuracy of computer-assisted total knee arthroplasty related to extra-articular tibial deformities

OBJECTIVE

To compare the accuracy of postoperative mechanical alignment in computer-assisted total knee arthroplasties (CAS-TKA) related to various degrees of extra-articular tibial deformity.

METHODS

We performed CAS-TKA on 30 knee models in which extra-articular proximal tibial deformities were preset to have malalignments ranging from 30° of varus to 30° of valgus. The knees were assigned to two groups, designated Group A (knees with ≤ 15° preoperative malalignment) and Group B (knees with > 15° preoperative malalignment), and the postoperative mechanical alignment in the two groups was compared using a computer-assisted surgery (CAS) system. Resected bone pieces from the distal femurs and proximal tibias were measured with a digital Vernier caliper and the results compared with the CAS calculations to evaluate the execution accuracy of the bone resection.

RESULTS

There was no outlier in either group when a ± 3° deviation from neutral mechanical alignment was set as the acceptance criterion. Interestingly, Group B showed significantly more outliers when the acceptance criterion was a deviation of ± 2° (26.67%, p = 0.0317) or ± 1° (6.67%, p = 0.0007) from neutral alignment. There was no statistical difference between the groups in terms of the execution accuracy of the bone resection.

DISCUSSION

The CAS-TKA approach provided significantly less alignment accuracy in tibia with greater preoperative frontal deformity, despite there being no outliers beyond ± 3°.

Relationship of plasma and synovial fluid vascular endothelial growth factor with radiographic severity in primary knee osteoarthritis

PURPOSE

Recent evidence suggests that angiogenesis and inflammation contribute to the development and progression of osteoarthritis (OA). The purpose of this study was to investigate vascular endothelial growth factor (VEGF) levels in plasma and synovial fluid of patients with knee OA and to determine the relationship of VEGF levels with disease severity in knee OA.

METHODS

A total of 100 subjects were enrolled in this study (80 knee OA patients and 20 healthy controls). Plasma and synovial fluid VEGF levels were analysed using enzyme-linked immunosorbent assay. VEGF expressions in synovial membrane and articular cartilage samples were assessed using immunohistochemistry.

RESULTS

VEGF level in synovial fluid of knee OA patients was tenfold higher than that in paired plasma (P < 0.001). Both plasma and synovial fluid VEGF exhibited a positive correlation with radiographic severity (r = 0.454 and r = 0.727, P < 0.001, respectively). VEGF expression was highly detectable in synovial lining cells and articular chondrocytes of knee OA patients.

CONCLUSIONS

VEGF levels in both plasma and synovial fluid were positively correlated with the severity of knee OA. Therefore, VEGF may be useful for monitoring OA severity and could play a substantial role in the development and progression of knee OA.

Gap changes after popliteus-tendon resection in PS-TKA: a cadaveric study in Thai female knees

Popliteus-tendon injury during total knee arthroplasty (TKA) may result in imbalanced soft-tissue tension; however, it is unclear whether complete popliteus-tendon resection is a factor which contributes to knee instability following TKA. We performed an isolated complete resection of the popliteus tendon during a standard posterior stabilised TKA (PS-TKA) in 14 normal knees of Thai female cadavers and measured gap differences in both knee flexion and extension. In addition, we measured the distance from the femoral attachment of the popliteus tendon to the femoral condyles including the distance from the most distal femoral attachment of the popliteus tendon to the distal lateral femoral condyle (DFa-DLFC), and the distance from the most posterior femoral attachment of the popliteus tendon to the posterior lateral femoral condyle (PFa-PLFC). After completion of bone cuts, static flexion and extension gaps were measured with a tension of 98 N under intact and complete tendon resection, respectively. The mean DFa-DLFC and PFa-PLFC distances were 8.9 mm (range, 6.4-10.5mm) and 11.5mm (range, 9.5-14.0mm), respectively. Of 14 cadaveric knees, 35.7% had a DFa-DLFC distance <9 mm. Flexion and extension gaps significantly increased in both medial and lateral sides after complete popliteus resection with a similar mean increased value of 1.85 mm. The clinical evaluation of gap changes after popliteus resection on knee stability should be further investigated. A routine 9-mm distal femoral bone cut may injure the popliteus tendon during TKA conducted on small knees.

Contemporary pain management in total knee arthroplasty

Pain management has become a very important part of postoperative care for total knee arthroplasty patients. Contemporary pain control has evolved from high-dose opioid in the past to state-of-the-art multimodal regimens. These include multiple non-opioid medication such as NSAIDs, COX-2 inhibitors, and gabapentinoid, and novel anesthetic techniques such as preemptive analgesia and ultrasound-guided peripheral nerve blocks. Another method which is gaining popularity is intraarticular injection of anesthetic cocktail during surgery. Pre-op education can also help patients cope with their pain better.

The early results of gender-specific total knee arthroplasty in Thai patients

We prospectively evaluated a consecutive series of 314 patients (265 females and 49 males) who underwent unilateral TKA and received an average of 2 years of follow-up. In all patients, a standard (STD) or a gender-specific (GS) femoral component was selected based on the presentation of intra-operative medio-lateral overhanging of the femoral cutting guide over the femoral condyle. There were no significant differences in the pre-operative parameters of both groups. At the last follow-up, both STD and GS groups had similarly improved KS clinical scores (92.9 vs. 92.1 points), function scores (89.5 vs. 89.7 points) and ROM (133.5° vs. 134.1°) with no difference in the rate of lateral retinacular release. The overall percentage of the GS component selection was 52.5% (165/314) and was significantly higher in female patients than male patients (60.8% vs. 8.2%, p<0.0001). In addition, selected GS prostheses increased significantly with increasing femoral size (25% for size C, 53% for size D, 86% for size E, and 100% for size F, respectively). There were no complications or early loosening related to the GS prosthesis. The mean post-operative limb alignment was 5.5° of the anatomical valgus with no difference between groups. We concluded that the GS femoral component did not provide better clinical outcomes than the standard femoral component; however, it provided surgical ease to minimize prosthesis overhanging in patients with narrow femoral condyles.

Inflammation related to synovectomy during total knee replacement in patients with primary osteoarthritis: a prospective, randomised study

We compared inflammation in the knee after total knee replacement (TKR) for primary osteoarthritis between two groups of patients undergoing joint replacement with and without synovectomy. A total of 67 patients who underwent unilateral TKR were randomly divided into group I, TKR without synovectomy, and group II, TKR with synovectomy. Clinical outcomes, serial serum inflammatory markers (including interleukin-6 (IL-6), CRP and ESR) and the difference in temperature of the skin of the knee, compared with the contralateral side, were sequentially evaluated until 26 weeks after surgery. Pre-operatively, there were no statistically different clinical parameters between groups I and II. At the 26-week follow-up, both groups had a similarly significantly improved American Knee Society clinical score (p < 0.001) and functional score (p < 0.001) with no differences between the groups. Similar changes in serial inflammatory markers were found in both groups, including mean peak levels of IL-6 (189 pg/ml (SD 53.4) versus 201 pg/ml (SD 49.4) for groups I and II, respectively) and CRP (91 mg/L (SD 24.1) versus 88 mg/L (SD 23.4), respectively) on the first post-operative day, returning to pre-operative values at two and six weeks, respectively. The mean peak level of ESR for the respective two groups was 46 mm/hr versus 48 mm/hr at two weeks, which had still not returned to its pre-operative mean value at 26 weeks. The elevation in the skin temperature appeared to mirror the peak elevation of the ESR, with a range of 2.5° C to 4.5° C with some reduction at 26 weeks but still exceeding the pre-operative value. We concluded that synovectomy at the time of TKR does not provide any benefit to the clinical outcome or shorten the duration of the inflammatory response after surgery.

Dickkopf-1 (Dkk-1) in plasma and synovial fluid is inversely correlated with radiographic severity of knee osteoarthritis patients

Background

Osteoarthritis (OA) is a common degenerative joint disease causing pain, stiffness, reduced motion, swelling, crepitus, and disability. Dickkopf-1 (Dkk-1) is a critical mediator of osteoblastogenesis and regulates the joint remodeling. The aim of this study was to examine plasma and synovial fluid Dkk-1 levels of patients with primary knee OA and to investigate their relationship with disease severity.

Methods

Thirty-five patients aged 55-83 years with knee OA and 15 healthy individuals were recruited into this study. Disease severity was determined using weight-bearing anteroposterior radiographs of the affected knee. The radiological grading of OA in the knee was performed according to the Kellgren-Lawrence grading system. Dkk-1 levels in both plasma and synovial fluid were evaluated using enzyme-linked immunosorbent assay.

Results

The average concentration of circulating Dkk-1 in the knee OA patients was remarkably lower than that of healthy controls (396.0 ± 258.8, 95%CI 307.1-484.9 vs 2348.8 ± 2051.5, 95%CI 1164.3-3533.3 pg/ml, p < 0.0001). Dkk-1 levels in synovial fluid were significantly lower than in paired plasma samples (58.6 ± 31.8, 95%CI 47.7-69.6 vs 396.0 ± 258.8, 95%CI 307.1-484.9 pg/ml, p < 0.001). Furthermore, both plasma and synovial fluid Dkk-1 levels were inversely correlated with radiographic severity (r = -0.78, p < 0.001 and r = -0.42, p = 0.01, respectively). Plasma Dkk-1 levels were also significantly correlated with synovial fluid Dkk-1 levels (r = 0.72, p < 0.001).

Conclusions

Dkk-1 levels in plasma and synovial fluid are inversely related to the severity of joint damage in knee OA. Dkk-1 could serve as a biochemical marker for determining disease severity and might play a potential role in the pathogenesis of the degenerative process of OA.

Comparable clinical outcomes between glucosamine sulfate-potassium chloride and glucosamine sulfate sodium chloride in patients with mild and moderate knee osteoarthritis: a randomized, double-blind study

BACKGROUND

Glucosamine sulfate has been recommended for treatment of knee osteoarthritis in several published guidelines. However, there are various preparations of glucosamine that may result in different pharmacokinetic and clinical outcomes.

OBJECTIVES

Comparison of clinical outcomes of two different preparations of glucosamine sulfate (Sodium chloride salt and Potassium chloride salt) in patients with mild and moderate degree knee osteoarthritis. Laboratory tests to monitor drug safety were also studied.

MATERIAL AND METHOD

Patients with symptomatic mild and moderate degree knee osteoarthritis were randomly assigned to receive treatment with either glucosamine sulfate with potassium salt (GS-K) 1500 mg daily or glucosamine sulfate with sodium salt (GS-Na) 1500 mg daily. Types of treatments were blinded to both patients and evaluators. Clinical assessments were done two weeks prior to initiation of treatment and then every four weeks until the sixteen week of treatment. Standing knee radiographs were taken at the initial visit. Patients with Ahlback stage 1 to 4 were included in the current study. Clinical data included range of motion, presence or absence of joint effusion, WOMAC and SF36. Laboratory studies were also done to evaluate drug safety, including BUN, creatinine, electrolytes, and liver function test. Adverse drug reactions were also recorded.

RESULTS

Ninety patients with mild and moderate knee osteoarthritis (Ahlback grade 1-4) were randomized to two treatment groups, forty-five patients each. Demographic data and initial clinical assessment were similar in both groups. Both groups demonstrated improvement of WOMAC score and SF-36 at final follow-up but this did not reach statistical significance. Differences of WOMAC score and SF-36 between the two groups were not significant at any follow-up visit. Serum potassium level increased more significantly in the GS-K group but did not exceed normal value.

CONCLUSION

In this short-term randomized comparison, glucosamine sulfate with potassium salt (GS-K) is as effective in pain relief and as safe as glucosamine sulfate with sodium salt (GS-Na) for treatment of mild and moderate degree knee osteoarthritis.

Relationship of serum IL-6, C-reactive protein, erythrocyte sedimentation rate, and knee skin temperature after total knee arthroplasty: a prospective study

Knee osteoarthritis is a common cause of severe pain and functional limitation. Total knee arthroplasty is an effective procedure to relieve pain, restore knee function, and improve quality of life for patients with end stage knee arthritis. The aim of this study was to investigate the inflammatory process in patients with primary knee osteoarthritis before surgery and in subsequent periods following total knee arthroplasty. A prospective study of 49 patients undergoing primary total knee replacements was conducted. The patients were evaluated by monitoring serum interleukin-6 (IL-6), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), knee skin temperature, and clinical status. Measurements were carried out preoperatively and postoperatively on day one and at two, six, 14, and 26 weeks during follow-up review in the knee clinic. The serum IL-6 and CRP were elevated on the first postoperative day but fell to preoperative values at two weeks postoperatively. Both returned to within the normal range by six weeks postoperatively. In addition, the postoperative ESR showed a slow rise with a peak two weeks after surgery and returned to the preoperative level at 26 weeks postoperatively. The difference in skin temperature between operated and contralateral knees had a mean value of +4.5°C at two weeks. The mean value decreased to +3.5°C at six weeks, +2.5°C at 14 weeks, and +1.0°C at 26 weeks. The difference in skin temperature decreased gradually and eventually there was no statistically significant difference at 26 weeks after surgery. A sustained elevation in serum IL-6, CRP, ESR, and skin temperature must raise the concern of early complication and may suggest the development of postoperative complication such as haematoma and/or infection.

Relationship of plasma and synovial fluid BMP-7 with disease severity in knee osteoarthritis patients: a pilot study

The objective of this study was to investigate bone morphogenetic protein-7 (BMP-7) levels in both plasma and synovial fluid of patients with primary knee osteoarthritis (OA) and to determine their relationship to disease severity. Thirty-two patients with knee OA and 15 healthy subjects were enrolled in the study. Anteroposterior knee radiographs were taken to determine the disease severity of the affected knee. The radiographic grading of OA in the knee was performed using the Kellgren-Lawrence criteria. BMP-7 levels in the plasma and synovial fluid were measured using enzyme-linked immunosorbent assay. The mean plasma BMP-7 concentration of the knee OA patients was significantly higher compared with that of healthy controls (12.1 +/- 1.6 vs 3.5 +/- 0.9 pg/ml, P = 0.001). Although BMP-7 levels in plasma were higher with respect to paired synovial fluid samples, the difference was not statistically significant (12.1 +/- 1.6 vs 10.5 +/- 2.2 pg/ml, P = 0.3). Subsequent analysis showed that plasma BMP-7 levels significantly correlated with disease severity (r = 0.77, P < 0.001). Furthermore, the synovial fluid levels of BMP-7 also correlated with disease severity (r = 0.60, P < 0.001). In addition, plasma BMP-7 levels showed a positive correlation with synovial fluid BMP-7 levels (r = 0.71, P < 0.001). Overexpression of BMP-7 in plasma and synovial fluid is related to progressive joint damage in knee OA. These findings suggest that BMP-7 might serve as a biochemical parameter for determining disease severity in primary knee OA and could play a potential role in cartilage protection and repair of OA.

The effect of knee flexion during tourniquet inflation, fat pad excision and lateral tibial release on patellar subluxation during MIS TKA

We compared the distance of patellar subluxation (lateral patellar displacement) during MIS TKA arthrotomy among sequential variations of tourniquet application and soft tissue release in a consecutive series of 40 knees. The distance of patellar subluxation from the Whiteside's line was measured for every knee under four consecutive conditions; A) the tourniquet inflated with knee in full extension, B) no tourniquet pressure applied, C) the tourniquet inflated with knee in deep flexion, and D) the tourniquet inflated with knee in deep flexion and lateral tibial release (a limited subperiosteal soft tissue dissection including limited patellar fat pad excision and limited capsular release from the upper lateral tibial plateau). There were 28 women and 12 men with the average age of 70 years and the average BMI of 25.5. All knees had preoperative flexion more than 110 degrees . The tourniquet pressure ranged from 280 to 300 mm Hg. The average skin incision length was 9 cm. The average measured distance of condition A, B, C and D were 10, 14.5, 15.8 and 22 mm, respectively with significant difference (p<0.001). The distance of patellar subluxation correlated between conditions A) and C) (r(2), 0.67) and between conditions C) and D) (r(2), 0.72) in the studied group. However, there was no statistical difference of measured distance between group with condition B and C (p=0.40). In conclusion, when MIS TKA is performed using the tourniquet, inflating the tourniquet with knee in deep flexion provided better arthrotomy exposure than the knee in full extension. Combined inflating tourniquet in deep knee flexion and lateral tibial release provided the greatest arthrotomy visualization.

Rapid ambulation and range of motion after minimally invasive total knee arthroplasty

The authors evaluated the intraoperative data and early clinical results of 22 minimally invasive mini-incision total knee arthroplasties (mini-incision TKAs) performed between October 2002 and September 2003. Results were matched with 22 patients who underwent standard TKA in the same period. At a minimum 12-week follow up, results comparing the mini-incision TKA group and the standard TKA group were evaluated as follows: The average operative time was 137.1 vs 115.8min (p=0.02), the average wound length was 9.4 vs 13.7 cm, the average blood loss was 456 vs 512 ml (p=0.14) and the number of patients who could start to walk on postoperative day one was 17 vs 2. On postoperative day one, 82% of the mini-incision TKA group could do active knee extension meanwhile none of the standard group could. Postoperative pain score was not different at 24 hours or 48 hours. At 2 and6 weeks, the mini-incision TKA group had less pain with significant difference (p=0.002 and p=0.002). The postoperative range of motion in the mini-incision group was also significantly improved at 2 weeks (p=0.03). However, pain and range of motion were not different in both groups after 12 weeks. Early results of mini-incision TKA accelerated patient postoperative activity, ambulation and range of motion.

Contralateral total knee arthroplasty after unilateral surgery in bilateral varus gonathrosis

The authors retrospectively evaluated the rate of contralateral total knee arthroplasty (TKA) in 93 patients who had bilateral varus gonarthrosis and underwent unilateral TKA. Patients were divided into 3 groups according to degree of anatomical varus of the contralateral knee and/or contralateral knee pain at the time of first TKA. Group A, 25 patients, had no pain and within 10-degree deformity. Group B, 48 patients, had pain and within 10-degree deformity. Group C, 20 patients, had pain and more than 10-degree deformity. At a minimum of 2-years follow up after the first TKA, the mean function scores among the groups were significantly different (p < 0.0001). Seventy-five percent of group C, 34% of group B and 0% of group A underwent sequential contralateral TKA, respectively at average 6.7-month interval. Rate of contralateral TKA was high if patients had contralateral knee pain and more than 10 degrees of anatomical varus.