Implant alignment is an important factor affecting clinical results associated with total knee arthroplasty (TKA). No report exists showing the utility of an accelerometer-based portable navigation system among patients with marked femoral bowing. The aim of this study was to evaluate the accuracy of a portable navigation system for implant alignment in Asian patients with marked femoral bowing. The authors evaluated 142 consecutive TKAs performed for primary osteoarthritis since July 2013. A portable navigation system was used in 67 knees, and a conventional jig was used in 75 knees. The authors measured the mechanical axis and femoral/tibial component alignments on long-leg radiographs obtained 2 weeks after TKA. In addition, coronal bowing of the lower limb was evaluated. The results were analyzed in the general and marked femoral bowing subgroups. There were no significant differences between the 2 groups for demographic data. The rates of femoral component outliers in the coronal plane for the navigation system and conventional technique were 1.5% and 13.3% (P=.01), respectively. Marked femoral bowing was observed in 73 knees. In the subgroup of patients with marked femoral bowing, femoral coronal alignment and its outliers were more accurate in the navigation group (0%) than in the conventional group (16.2%) (P=.025). This is the first report to show the utility of an accelerometer-based portable navigation system for accurate prosthetic alignment among Asian patients with marked femoral bowing. The navigation system decreased outliers in coronal alignment of the femur, even in cases of marked femoral bowing, but did not increase complications. [Orthopedics. 2017; 40(3):e465-e472.].

Aims The aim of this study was to assess the effectiveness of perioperative essential amino acid (EAA) supplementation to prevent rectus femoris muscle atrophy and facilitate early recovery of function after total knee arthroplasty (TKA). Methods The study involved 60 patients who underwent unilateral TKA for primary knee osteo-arthritis (OA). This was a double-blind, placebo-controlled, randomized control trial with patients randomly allocated to two groups, 30 patients each: the essential amino acid supplementation (9 g daily) and placebo (lactose powder, 9 g daily) groups. Supplementation and placebo were provided from one week before to two weeks after surgery. The area of the rectus femoris muscle were measured by ultrasound imaging one month before surgery and one, two, three, and four weeks postoperatively. The serum albumin level, a visual analogue knee pain score, and mobility were also measured at each time point. The time to recovery of activities of daily living (ADLs) was recorded. Postoperative nutrition and physiotherapy were identical in both groups. Results The mean relative change from baseline was as follows for the amino acid group: 116% in rectus femoris muscle area (71% to 206%); 95% in serum albumin (80% to 115%) and 39% in VAS pain (0% to 100%) at four weeks after surgery. These values in the placebo group were: 97% in muscle area (68 to 155); 89% in serum albumin (71% to 100%) and 56% in VAS pain four weeks after surgery (0% to 100%). All changes were statistically significant (p < 0.05). The mean time to recovery of ADLs was shorter in the amino acid group compared with the placebo group (p = 0.005). Conclusion Perioperative essential amino acid supplementation prevents rectus femoris muscle atrophy and accelerates early functional recovery after TKA. Cite this article: Bone Joint J 2020;102-B(6 Supple A):10–18.

Adipose-derived stem cells (ADSCs) have anti-inflammatory and regenerative properties. The purpose of this study was to investigate the effect of locally administered ADSCs in a rheumatoid arthritis (RA) mouse model. In an in vivo experiment, single-cell ADScs and three dimensionally-cultured ADSc spheroids were injected intra-articularly into the knees of RA model mice and histologically assessed. Marked improvement of synovial inflammation and articular cartilage regeneration was found in ADSCtreated mice. Proliferation, migration, and apoptosis assays of synovial fibroblasts incubated with single-cell and spheroid ADSCs were performed. The expression levels of total cytokine RNA in ADSC single cells, spheroids, and ADSC-treated inflammatory synovial fibroblasts were also evaluated by quantitative reverse transcription PCR. ADSCs suppressed the proliferation and migration of activated inflammatory cells and downregulated inflammatory cytokines. TSG-6 and TGFβ1 were significantly upregulated in ADScs compared to controls and TGFβ1 was significantly upregulated in ADSC spheroids compared to single cells. The apoptosis rate of ADSC spheroids was significantly lower than that of single-cell ADSCs. These results indicated that intra-articular administration of ADSC single cells and spheroids was effective in an RA mouse model, offering a novel approach for the development of effective localized treatments for patients with RA. Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation and degeneration of articular cartilage and bone. In previous decades, systemic therapies, including methotrexate and biological disease-modifying antirheumatic drugs, significantly improved the treatment of synovial inflammation 1. Given that RA is a systemic disease, the focus has been to develop systemic treatments for it 2 ; however, swelling persists in some joints with such treatments and the application of systemic treatment is limited due to adverse, off-target effects. Therefore, localized treatment methods are important for treating RA. Corticosteroid injections are the most widely used localized treatment for RA. Although it reduces RA-associated synovitis, repeated intra-articular corticosteroid injections can lead to the degeneration of articular cartilage 3. Other adverse effects of corticosteroids include septic arthritis, local tissue atrophy, tendon rupture, and hyperglycaemia. Consequently, the development of safe, effective, and tissue-regenerating localized therapies must be explored. Recent studies in regenerative medicine have used mesenchymal stem cells (MSCs) derived from somatic tissues such as bone marrow, muscle, blood, and adipose tissue 4,5. MSCs exert anti-inflammatory effects, modulate the immune response, and modify the local microenvironment; furthermore, studies have reported their therapeutic effects for the treatment of inflammatory and autoimmune diseases 6,7. Considering the accessibility and ethical issues associated with the use of MSCs, adipose-derived stem cells (...

Purpose Two-dimensional (2D) and three-dimensional (3D) measurements of prosthetic alignment and "outliers" after total knee arthroplasty (TKA) might not necessarily be comparable. The aim of this study was to compare the use of 2D and 3D measurements in the identiication of prosthetic alignment and outliers after TKA. Methods This cross-sectional study included 159 consecutive TKAs. All patients underwent plain radiography, luoroscopyguided radiography, and computed tomography after TKA. The same baseline was used for 2D and 3D measurements. The reliability of prosthetic alignment and outlier identiication (> 3° from neutral alignment) was compared between the 2D and 3D measurements. ResultsThe mean prosthetic alignment and rate of outliers were not signiicantly diferent the between 2D and 3D measurements. The inter-and intra-observer reliabilities were higher for the 3D measurements than for the 2D measurements. The agreement between 2D and 3D measurements in outlier identiication was poor, except for femoral coronal alignment. Cohen's κ coeicients were 0.19 in femoral sagittal (poor), 0.02 in tibial coronal (poor), and 0.10 in tibial sagittal (poor) on plain radiography. The values were 0.23 in tibial coronal (poor) and 0.002 in tibial sagittal (poor) on luoroscopy-guided radiography. Conclusions The agreement between 2D and 3D measurements in the identiication of outliers was poor, even on luoroscopy-guided radiography. Since 2D measurements have an inherent risk of misidentifying alignment outliers, this inding is clinically relevant. To properly analyze the correlation between outliers and clinical results, such as longevity, patient satisfaction, and patient-reported outcome, 3D measurements for prosthetic alignment are desirable. Level of evidence III.

III.