Prevalence and Characteristics of Onychomycosis in Patients with Knee Osteoarthritis: A Single-centre Prospective Cross-sectional Study

Knee disorders that compromise patients’ lower leg movements and self-care may put these patients at greater risk of onychomycosis. However, little is known about the prevalence of onychomycosis in patients with knee diseases. This study evaluated the prevalence and characteristics of onychomycosis in patients with knee osteoarthritis. A total of 520 consecutive patients with symptomatic knee osteoarthritis who visited the Department of Orthopedics for a potential knee surgery were evaluated for onychomycosis by PCR-based reverse blot hybridization assay. Of the 520 patients, 308 (59.2%) were diagnosed with onychomycosis. Age (p = 0.004), male sex (p = 0.015), and being barefooted (p = 0.031) were statistically significant risk factors for onychomycosis. Knee disease severity, based on Kellgren-Lawrence grade, was associated with severity of onychomycosis. The impairment of physical function and self-care caused by knee disorders may increase the prevalence of onychomycosis in these patients.

Association of Gap Healing With Angle of Correction After Opening-Wedge High Tibial Osteotomy Without Bone Grafting

Background:

Studies have reported that opening wedge high tibial osteotomy (OWHTO) without bone grafting has outcomes that are similar to or even better than those of OWHTO with bone grafting, especially after use of a locking plate. However, a consensus on managing the gap after OWHTO has not been established.

Purpose:

To determine the degree of gap healing achieved without bone grafting, the factors associated with gap healing, and whether additional gap healing would be obtained after plate removal.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

This retrospective study included 73 patients who underwent OWHTO without bone grafting between 2015 and 2018. Patients in the study were divided into 2 groups based on the correction angle: small correction group (<10°; SC group) and large correction group (≥10°; LC group). The locking plate used in OWHTO was removed at a mean of 13.5 months after surgery in 65 patients. Radiographic indexes were measured: gap filling height, gap vacancy ratio (GVR), and osteotomy filling index. The acceptable gap healing was defined as an osteotomy filling index ≥3. The factors related to gap healing around the osteotomy site were selected after multicollinearity analysis.

Results:

Although both groups achieved acceptable gap healing regardless of the correction angle, the SC group showed higher and earlier gap healing than did the LC group (gap healing rate 81.4% in the SC group vs 41.7% in the LC group at 3 months postoperatively). The GVR was 8.6% in the SC group and 15.3% in the LC group at 12 months after surgery (P = .005). Both the amount of time that elapsed after surgery and the correction angle were associated with gap healing (P < .05). Additional gap healing was observed after plate removal, as the GVR decreased 2.7% more in the patients with plate removal than in patients who did not have plate removal (P = .012).

Conclusion:

All patients achieved acceptable gap healing without bone graft. The degree of gap healing was higher in the SC group and increased over time. Gap healing was promoted after plate removal. Considering the results of this study, a bone graft is not necessary in routine OWHTO in terms of gap healing.

Coordinate regulation of the senescent state by selective autophagy

Cellular senescence is a complex stress response implicated in aging. Autophagy can suppress senescence but is counterintuitively necessary for full senescence. Although its anti-senescence role is well described, to what extent autophagy contributes to senescence establishment and the underlying mechanisms is poorly understood. Here, we show that selective autophagy of multiple regulatory components coordinates the homeostatic state of senescence. We combined a proteomic analysis of autophagy components with protein stability profiling, identifying autophagy substrate proteins involved in several senescence-related processes. Selective autophagy of KEAP1 promoted redox homeostasis during senescence. Furthermore, selective autophagy limited translational machinery components to ameliorate senescence-associated proteotoxic stress. Lastly, selective autophagy of TNIP1 enhanced senescence-associated inflammation. These selective autophagy networks appear to operate in vivo senescence during human osteoarthritis. Our data highlight a caretaker role of autophagy in the stress support network of senescence through regulated protein stability and unravel the intertwined relationship between two important age-related processes.

Relationships between the changes in flexion contracture and standing flexion angle of the knee and sagittal spinal alignment after total knee arthroplasty

BACKGROUND

The sagittal spinal alignment interacts with the lower extremity in patients with combined degenerative disease of the spine and lower extremity. This study aimed to clarify the relationships between the reciprocal changes in sagittal alignment of the knee, pelvis, and spine after total knee arthroplasty (TKA) in osteoarthritis patients.

METHODS

Prospectively, 36 patients who underwent primary TKA for severe knee osteoarthritis were enrolled. Their clinical and radiological evaluation included assessments of the knee flexion contracture (KFC) and standing knee flexion angle (KFA), as well as spinopelvic parameters and the global sagittal spinal alignment from standing whole-lower-extremity and whole-spine radiographs preoperatively and at postoperative 2 weeks, 6 weeks, 6 months, 1 year, and 2 years. Linear mixed models were used to assess the relationships between KFC/KFA and between spinopelvic/global sagittal spinal alignments.

RESULTS

The KFC decreased abruptly immediately after TKA, and the correction was maintained for 2 years postoperatively. The KFA decreased gradually and approached the value of the KFC after 2 years. Of the spinopelvic parameters, sacral slope and pelvic incidence decreased significantly, in ways related to changes in KFA. There was no significant relationship between sagittal spinal alignment and postoperative changes in KFC.

CONCLUSION

Although the flexion contracture was corrected immediately after TKA, the standing KFA improved gradually over 2 years. The pelvic parameters showed compensatory changes according to the KFA. The decompensated sagittal spinal malalignment was not related to a relapse in flexion contracture.

Effects of preoperative, scheduled administration of antiemetics in reducing postoperative nausea and vomiting in patients undergoing total knee arthroplasty

There is no established protocol regarding the timing of administration of antiemetics in patients undergoing total knee arthroplasty (TKA). The purpose of this study was to determine whether preoperative, rather than postoperative administration of an antiemetic could reduce postoperative nausea and vomiting (PONV) in patients undergoing TKA, and whether there was a difference in postoperative pain, patient satisfaction and complications after TKA between the 2 different administration times.The included patients (N = 101) either received intravenous administration of the ramosetron 1 hour before surgery (N = 50) or at the end of surgery (N = 51) consecutively order. The incidence of PONV and the frequency of rescue medicine use were recorded until 48 hours postoperatively. The severity of postoperative pain and patient satisfaction were assessed using the visual analogue scale. The incidence of complications associated with use of antiemetic was assessed.Preoperative administration of ramosetron did not decrease PONV during the first 48 hours. There was no significant difference in the incidence of nausea and vomiting, use of rescue antiemetics, and the severity of nausea (P > .05). Postoperative pain, satisfaction scores, and the incidence of complications were not different between the 2 groups (P > .05).Preoperative administration of ramosetron did not show clinical advantage in reducing POVN, postoperative pain and improving patient satisfaction. However, the outcomes of complications were not inferior to those of postoperative administration. Therefore, under the current protocol of multimodal therapies, timing of administration of pre-emptive antiemetic did not have significant effect on PONV.

Retrospective study of relationship between vastus medialis volume on SPECT-CT and outcome of unilateral total knee arthroplasty

Although the importance of quadriceps femoris function was reported previously, little is known about volume-related factors and their effects on clinical outcomes after total knee arthroplasty (TKA). We sought to determine whether there was a bilateral difference in vastus medialis muscle volume measured on single-photon emission computed tomography-computed tomography (SPECT-CT) in patients who underwent unilateral TKA. We also aimed to determine whether vastus medialis volume was related to osteoarthritis (OA) severity or scintigraphic uptake degree around the knee joint on SPECT-CT. And finally, we attempted to investigate the factors, such as vastus medialis volume and scintigraphic uptake degree, associated with the functional outcomes of TKA.This retrospective study included 50 patients (41 female, 9 male) undergone unilateral TKA due to primary OA. The maximal cross-sectional area of the vastus medialis was measured on axial SPECT-CT images. Scintigraphic uptake degrees and Kellgren-Lawrence (K-L) grade at the tibiofemoral joints were assessed. We compared maximal cross-sectional area of the vastus medialis on SPECT-CT for difference of bilateral lower limbs. We also analyzed the relationship between volume of vastus medialis and scintigraphic uptake measured on SPECT-CT and the severity of OA on conventional radiographs. The clinical outcomes were evaluated using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index at baseline and at 1 and 2 years after surgery. The relationship between preoperative muscle volume and scintigraphic uptake on SPECT-CT and WOMAC index was analyzed.The amount of muscle volume measured on SPECT-CT was smaller in operated limb in patients who underwent unilateral TKA. Preoperative vastus medialis muscle volume was not related to preoperative OA severity measured on conventional radiographs and scintigraphic uptake on SPECT-CT. However, a decreased vastus medialis muscle volume was related to worse clinical outcomes after TKA (P = .045), whereas the degree of scintigraphic uptake on SPECT-CT was not associated with postoperative clinical outcomes.Muscle volume of vastus medialis was decreased in the operated knee than in the nonoperated knee, and that was correlated with worse postoperative results. Even if the preoperative volume of vastus medialis were not related to OA severity on conventional radiographs and scintigraphic uptake on SPECT-CT, preservation and improvement of the muscle mass of the knee undergoing TKA is important.

Current Trends and Projected Burden of Primary and Revision Total Knee Arthroplasty in Korea Between 2010 and 2030

BACKGROUND

This study aimed to (1) document the total knee arthroplasty (TKA) use in Korea from 2010 to 2018, (2) evaluate whether rapid increase in TKA use has been maintained, and (3) estimate the projected TKA burden to 2030 based on the current use.

METHODS

Using the Health Insurance Review and Assessment Korean database, procedural rate, growth rate, and revision burden of primary and revision TKAs in Korea between 2010 and 2018 were analyzed. TKA procedural numbers were also stratified by age and gender. Then, the projected TKA burden to 2030 including procedural number and medical costs were estimated using linear and quasi-Poisson regression models, respectively.

RESULTS

Between 2010 and 2018, procedural rate of primary and revision TKAs has increased by 35% and 68%, respectively. More than 85% of primary and revision TKAs were performed on female patients, and the subgroup of patients aged ≥80 years showed a marked increase in primary and revision TKA use. According to the projection model, the number of primary and revision TKAs is predicted to increase between 53% and 91%, and between 75% and 155%, respectively, by 2030.

CONCLUSION

Between 2010 and 2018, the procedural rates of primary and revision TKAs in Korea increased gradually by 35% and 68%, respectively, and previously observed striking growth rate has markedly slowed. Nevertheless, compared to 2018, the burdens of primary and revision TKAs are projected to increase up to 91% and 155%, respectively, by 2030.

LEVEL OF EVIDENCE

Therapeutic Level III.

Efficacy and safety of short-term use of a pelubiprofen CR and aceclofenac in patients with symptomatic knee osteoarthritis: A double-blinded, randomized, multicenter, active drug comparative, parallel-group, phase IV, non-inferiority clinical trial

INTRODUCTION

At present, information about clinical efficacy and adverse events of controlled release (CR) form of pelubiprofen, a prodrug of 2-arylopropionic acid with relatively selective effects on cyclooxygenase-2 activity, remains scarce. In this study, we sought to determine non-inferiority of pelubiprofen CR 90 mg/day compared to aceclofenac 200 mg/day regarding clinical efficacy and adverse events after a 4-week course of medication in the patients with symptomatic knee osteoarthritis.

MATERIALS AND METHODS

A total of 191 patients were randomly assigned to take either pelubiprofen CR 90 mg (n = 95) or aceclofenac 200 mg (n = 96). The primary outcome variable was non-inferiority of pain reduction between baseline and week 4 when assessed using a 100 mm pain visual analogue scale (VAS). Pelubiprofen was considered non-inferior to aceclofenac if the upper limit of the one-sided 97.5% confidence interval for the difference in terms of pain VAS was above 15 mm (the average change of pain VAS in the pelubiprofen group-pain VAS reduction in the aceclofenac group). Secondary outcome variables were the changes in 100 mm pain VAS at week 2 versus baseline, K-Western Ontario, and McMaster University Arthritis Index (K-WOMAC) changes at weeks 2 and 4 as compared to baseline, patient global assessment at weeks 2 and 4. The frequency and amount of rescue medicine usage at weeks 2 and 4 were also evaluated as the secondary outcome variable. For safety analysis, adverse events, clinical laboratory tests, vital signs, and physical examinations were assessed and conducted at each follow-up visit.

RESULTS

At week 4, the pain VAS values were significantly reduced in both groups receiving either pelubiprofen CR 90 mg or aceclofenac 200 mg as compared to the baseline. However, the pelubiprofen group and the aceclofenac group respectively showed the pain VAS changes of -22 and -21.9 in the pre-protocol set and -20.8 and -21.7 in the full analysis set, confirming non-inferiority. The pelubiprofen CR 90 mg showed a reduced incidence of adverse events compared to the aceclofenac 200 mg (p = 0.005).

CONCLUSIONS

Pelubiprofen CR 90 mg is as effective as aceclofenac 200 mg with reduced adverse events for the treatment of symptomatic knee osteoarthritis.

Microfractures Versus a Porcine-Derived Collagen-Augmented Chondrogenesis Technique for Treating Knee Cartilage Defects: A Multicenter Randomized Controlled Trial

PURPOSE

The purpose of this study was to evaluate the clinical efficacy and safety of treating patients with a cartilage defect of the knee with microfractures and porcine-derived collagen-augmented chondrogenesis technique (C-ACT).

METHODS

One hundred participants were randomly assigned to the control group (n = 48, microfracture) or the investigational group (n = 52, C-ACT). Clinical and magnetic resonance imaging (MRI) outcomes were assessed 12 and 24 months postoperatively for efficacy and adverse events. Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) assessment was used to analyze cartilage tissue repair. MRI outcomes for 50% defect filling and repaired tissue/reference cartilage (RT/RC) ratio were quantified using T2 mapping. Clinical outcomes were assessed using the visual analogue scale (VAS) for pain and 20% improvement, minimal clinically important difference (MCID), and patient acceptable symptom state for Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee score.

RESULTS

MOCART scores in the investigation group showed improved defect repair and filling (P = .0201), integration with the border zone (P = .0062), and effusion (P = .0079). MRI outcomes showed that the odds ratio (OR) for ≥50% defect filling at 12 months was statistically higher in the investigation group (OR 3.984, P = .0377). Moreover, the likelihood of the RT/RC OR becoming ≥1 was significantly higher (OR 11.37, P = .0126) in the investigation group. At 24 months postoperatively, the OR for the VAS 20% improvement rate was significantly higher in the investigational group (OR 2.808, P = .047). Twenty-three patients (52.3%) in the control group and 35 (77.8%) in the investigation group demonstrated more than the MCID of KOOS pain from baseline to 1 year postoperatively, with a significant difference between groups (P = .0116).

CONCLUSION

In this multicenter randomized trial, the addition of C-ACT resulted in better filling of cartilage defect of the knee joint.

LEVEL OF EVIDENCE

Level Ⅰ, Multicenter Randomized Controlled Trial.

Stress-activated miR-204 governs senescent phenotypes of chondrocytes to promote osteoarthritis development

A progressive loss of cartilage matrix leads to the development of osteoarthritis (OA). Matrix homeostasis is disturbed in OA cartilage as the result of reduced production of cartilage-specific matrix and increased secretion of catabolic mediators by chondrocytes. Chondrocyte senescence is a crucial cellular event contributing to such imbalance in matrix metabolism during OA development. Here, we identify miR-204 as a markedly up-regulated microRNA in OA cartilage. miR-204 is induced by transcription factors GATA4 and NF-κB in response to senescence signals. Up-regulated miR-204 simultaneously targets multiple components of the sulfated proteoglycan (PG) biosynthesis pathway, effectively shutting down PG anabolism. Ectopic expression of miR-204 in joints triggers spontaneous cartilage loss and OA development, whereas miR-204 inhibition ameliorates experimental OA, with concomitant recovery of PG synthesis and suppression of inflammatory senescence-associated secretory phenotype (SASP) factors in cartilage. Collectively, we unravel a stress-activated senescence pathway that underlies disrupted matrix homeostasis in OA cartilage.

Bone Mineral Density Around the Knee Joint: Correlation With Central Bone Mineral Density and Associated Factors

INTRODUCTION

The aims of this study were to (1) assess the bone mineral density (BMD) around the knee joint, (2) determine the correlation between central and knee BMDs, and (3) investigate the factors associated with BMD around the knee joint in patients with knee osteoarthritis (OA).

METHODOLOGY

This cross-sectional study included 122 patients who underwent total knee arthroplasty. Central and knee dual-energy X-ray absorptiometry was performed preoperatively. BMD at 6 regions of interest (ROIs) around the knee joint were measured, and their correlations with central BMD were determined using Spearman's correlation analysis. Lower limb alignment, severity of OA, body mass index (BMI), preoperative functional and pain scores were assessed to elucidate the factors associated with knee BMD using linear regression analysis.

RESULTS

Around the knee joint, BMD was the lowest at the distal femoral metaphysis and lateral tibial condyle. Knee BMD was significantly correlated with central BMD. However, the correlation coefficients varied by the ROI. Additionally, multivariate analysis revealed different associations with respect to the regions around the knee joint. Varus alignment of the lower limb was associated with increased BMD of the medial condyles and decreased BMD of lateral condyles. High grade OA was a protective factor; it was associated with increased BMD at the lateral condyles of the femur and tibia. Higher BMI was an independent protective factor in all ROIs around the knee joint except the lateral femoral condyles. Lower functional level was not associated with decreased BMD, whereas a higher pain score was significantly associated with lower BMD at the proximal tibial metaphysis.

CONCLUSIONS

Knee BMD was significantly correlated with central BMD. However, the correlations varied with the regions around the knee joint probably due to their independent association with the alignment of the lower limb, severity of OA, BMI, and preoperative pain level.

A retrospective comparative study of infection control rate and clinical outcome between open debridement using antibiotic-impregnated cement beads and a two-stage revision in acute periprosthetic knee joint infection

The aim of this study was to determine whether the infection control rate of a modified debridement, antibiotics, and implant retention (DAIR) protocol (DAIR with antibiotic-impregnated cement beads) is comparable to that of 2-stage revision for acute periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). We also aimed to determine whether this modified DAIR technique produced better clinical results than those obtained using 2-stage revision in terms of functional outcome, range of motion (ROM), and patient satisfaction at 2 years after surgery.This retrospective comparative study included patients who underwent modified DAIR (7 patients, 9 knees) or 2-stage revision (8 patients, 9 knees) for acute PJI of the knee joint. Infection control rate, functional outcome measured using Western Ontario and McMaster Universities Arthritis Index (WOMAC) score, ROM and patient satisfaction were compared between the two groups.There was no difference in infection control rates between the modified DAIR and 2-stage revision groups (78% vs 78%, respectively). In contrast, surgical outcome in the modified DAIR group was tended to be better than 2-stage revision group, but it did not reach statistical significance. Median maximal range of flexion was 103° in the modified DAIR group and it was 90° in the 2-stage group (P = .191). In addition, the median WOMAC function score was 24 in the modified DAIR group and it was 30 in the 2-stage group (P = .076). Median patient satisfaction measured using visual analogue scale was 8 in the modified DAIR group and 5 in the 2-stage group (P = .069).The infection control rates of the modified DAIR protocol and 2-stage revision protocol were similar for the treatment of acute PJI of the knee joint. However, the modified DAIR protocol could not provide substantially increased functional outcomes and patient satisfaction compared to 2-stage revision. Therefore, the modified DAIR technique should be considered to be of limited use in patients with high surgical morbidity.

Posterior condylar offset changes and its effect on clinical outcomes after posterior-substituting, fixed-bearing total knee arthroplasty: anterior versus posterior referencing

Background

We sought to determine whether there was a difference in the posterior condylar offset (PCO), posterior condylar offset ratio (PCOR) and clinical outcomes following total knee arthroplasty (TKA) with anterior referencing (AR) or posterior referencing (PR) systems. We also assessed whether the PCO and PCOR changes, as well as patient factors were related to range of motion (ROM) in each referencing system.

Methods

This retrospective study included 130 consecutive patients (184 knees) with osteoarthritis who underwent primary posterior cruciate ligament (PCL)-substituting fixed-bearing TKA. The difference between preoperative and postoperative PCO and PCOR values were calculated. Clinical outcomes including ROM and Western Ontario and McMaster University (WOMAC) scores were evaluated. Furthermore, multiple linear regression analysis was performed to determine the factors related to postoperative ROM in each referencing system.

Results

The postoperative PCO was greater in the AR group (28.4 mm) than in the PR group (27.4 mm), whereas the PCO was more consistently preserved in the PR group. The mean postoperative ROM after TKA was greater in the AR group (129°) than in the PR group (122°), whereas improvement in WOMAC score did not differ between the two groups. Preoperative ROM was the only factor related to postoperative ROM in both groups.

Conclusions

There was no difference in postoperative PCO in AR and PR group and the PCO was not associated with postoperative ROM. PCO was more consistently preserved after surgery in the PR group. The postoperative PCO and PCOR changes did not affect the postoperative ROM. Furthermore, similar clinical outcomes were achieved in the AR and PR groups.

Trial registration

Retrospectively registered (Trial registration number: 06-2010-110).

Reduction and fixation of anterior inferior tibiofibular ligament avulsion fracture without syndesmotic screw fixation in rotational ankle fracture

Objective

We aimed to present the radiographic and functional outcomes of anatomical reduction and fixation of anterior inferior tibiofibular ligament (AITFL) avulsion fracture without syndesmotic screw fixation in rotational ankle fracture.

Methods

We retrospectively reviewed 66 consecutive patients with displaced malleolar fracture combined with AITFL avulsion fracture. We performed reduction and fixation for the AITFL avulsion fracture when syndesmotic instability was present after malleolar fracture fixation. A syndesmotic screw was inserted only when residual syndesmotic instability was present even after AITFL avulsion fracture fixation. The radiographic parameters were compared with those of the contralateral uninjured ankles. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores were assessed 1 year postoperatively.

Results

Fifty-four patients showed syndesmotic instability after malleolar fracture fixation and underwent reduction and fixation for AITFL avulsion fracture. Among them, 45 (83.3%) patients achieved syndesmotic stability, while 9 (16.7%) patients with residual syndesmotic instability needed additional syndesmotic screw fixation. The postoperative radiographic parameters were not significantly different from those of the uninjured ankles. The mean AOFAS score was 94.

Conclusion

Reduction and fixation of AITFL avulsion fracture obviated the need for syndesmotic screw fixation in more than 80% of patients with AITFL avulsion fracture and syndesmotic instability.

Development and validation of a prediction model for knee joint line orientation after high tibial osteotomy

Background

Maintenance of optimal knee joint line orientation (KJLO) is important after high tibial osteotomy (HTO). No tools, however, are currently available that could predict the value of postoperative KJLO before surgery. First, this study sought to determine the effects of various preoperative anatomical alignment parameters to postoperative KJLO. Based upon these analyses, we aimed to devise an equation that predicts the value of postoperative KJLO.

Methods

A total of 14 radiographic parameters were measured in preoperative and postoperative full-limb standing anteroposterior radiographs on 50 patients who underwent open-wedge HTO. The parameters were analysed using multivariable linear regression to predict KJLO after HTO. External validation of the equation was done with 20 patients who underwent HTO at another institution.

Results

After HTO, KJLO increased from − 0.8° to 2.9° (P < 0.001). Based on the multivariable linear regression analysis, an equation was derived that can estimate postoperative KJLO after HTO; postoperative KJLO(°) = 1.029 + 0.560 × preoperative KJLO(°) + 0.310 × preoperative tibia plateau inclination(°) + 0.463 × aimed correction angle(°). The adjusted coefficients of determination value for this equation was 0.721. The equation also showed good calibration and predictability in external validation with predicted squared correlation coefficient of 0.867.

Conclusions

This study analysed the effects of preoperative anatomical alignment parameters on the postoperative KJLO. An equation which predicts postoperative KJLO with preoperative anatomical alignment factors was devised and validated. This equation would help in selecting optimal patients for HTO and in selecting the optimal target correction angle in HTO.

Management and clinical outcomes of periprosthetic fractures after total knee arthroplasty with a stem extension

There is little information about the management and clinical outcomes of the periprosthetic fracture after total knee arthroplasty (TKA) with a stem extension. The purposes of this study were to demonstrate management of the periprosthetic fractures after TKA with a stem extension, to report treatment outcomes, and to determine whether dual-plate fixation is superior to single-plate fixation regarding the radiographic bone union time and incidence of metal failure.This retrospective study included 15 knees with periprosthetic fractures after TKA using a stem extension. We demonstrated the fracture characteristics and management according to the fracture location and implant stability. The radiographic union time was determined. Complications, range of motion, and functional outcomes, including Western Ontario and McMaster Universities Osteoarthritis Index and Knee Society Score were assessed. Periprosthetic fractures after TKA with stem extension were 1 metaphyseal fracture without implant loosening, 7 diaphyseal fractures adjacent to the stem without implant loosening, 3 diaphyseal fractures away from the stem without implant loosening, and 4 fractures with implant loosening.Treatment included immobilization using a long leg cast, open reduction and internal fixation (ORIF), and re-revision TKA. There was no difference in functional outcomes and range of motion pre- and posttreatment. The complications included 2 cases of subsequent implant loosening. Patients in the dual-plating required a shorter bony union time than those in the single-plating (2.4 ± 1.1 vs 7.4 ± 2.2 months; P = .003).Periprosthetic fractures after TKA with stem extension could be managed individually according to the fracture location and implant stability. Complications were not uncommon even if patients were able to return to their preinjury functional level posttreatment. To avoid complications after ORIF, the dual plate was superior to the single plate, and subtle implant loosening should not be overlooked.

Temporal Value of C-Reactive Protein and Erythrocyte Sedimentation Rate after Total Knee Arthroplasty in Patients with Elevated Preoperative C-Reactive Protein: A Matched-Pair Analysis

BACKGROUND

We aimed to determine whether temporal values of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) after total knee arthroplasty (TKA) differ between patients with and without elevated preoperative CRP. We hypothesized that temporal pattern of CRP and ESR change would differ between the two groups.

MATERIALS AND METHODS

This retrospective study included 30 TKAs with a diagnosis of osteoarthritis with elevated preoperative CRP (>1 mg/dl) without clinical signs and symptoms of infection before surgery (elevated CRP group). Patients without elevated preoperative CRP were matched in a 1:10 fashion according to age, sex, number of comorbidities and whether TKA was unilateral or bilateral (nonelevated CRP group). The temporal values of CRP and ESR after TKA were compared between the two groups until 2 months after surgery.

RESULTS

The mean peak values of CRP and ESR after surgery were similar between the two groups in both unilateral and bilateral TKAs. In the unilateral TKA, mean values of CRP and ESR and the proportions of the knees with normal CRP and ESR at 2 months after surgery were similar in the two groups. However, in the bilateral TKA, mean values of CRP and ESR were higher and the proportions of the knees with normal CRP and ESR at 2 months after surgery were lower in the elevated CRP group compared to the nonelevated CRP group.

CONCLUSIONS

When performing TKA in patients with elevated preoperative CRP, the fact that the levels of CRP and ESR may not be normalized until 2 months after surgery should be considered during followup.

Relationship Between Coronal Alignment and Rotational Profile of Lower Extremity in Patients With Knee Osteoarthritis

BACKGROUND

We aimed at determining whether the coronal alignment of lower extremity was related to rotational geometry of distal femur, femoral anteversion, and tibial torsion in patients with knee osteoarthritis.

METHODS

A total of 422 lower extremities were divided into 3 groups according to the coronal alignment: valgus (n = 31), neutral (n = 78), and varus group (n = 313). Condylar twisting angle was measured to determine rotational geometry of distal femur as the angle between the clinical transepicondylar axis and the posterior condylar line. Femoral anteversion was assessed using the angle between a line intersecting the femoral neck and the posterior condylar line (pFeAV) and the angle between the same line and transepicondylar axis that is not affected by posterior condylar variations (tFeAV). Tibial torsion was evaluated by measuring the angle between the posterior condyles of the proximal tibia and the transmalleolar axis.

RESULTS

As the coronal alignment changed from varus to valgus, the condylar twisting angle increased (r = 0.253, P < .001; 6.6° in varus, 7.4° in neutral, and 10.2° in valgus group). Although the pFeAV also increased (r = 0.145, P = .003), the tFeAV did not change significantly (P = .218). Mean tFeAV was 4.3° in varus, 4.7° in neutral, and 6.5° in valgus group. In contrast, as the coronal alignment changed from varus to valgus, the external tibial torsion increased (r = 0.374, P < .001; 22.6° in varus, 26.3° in neutral, and 32.6° in valgus group).

CONCLUSION

The change patterns of the rotational profiles of the lower extremity according to the coronal alignment should be considered in order to obtain satisfactory rotational alignment after TKA.

Prevalence of excessive lateral pressure syndrome in varus osteoarthritic candidates for high tibial osteotomy

BACKGROUND

This study aimed to determine the prevalence of excessive lateral pressure syndrome (ELPS) in potential candidates for high tibial osteotomy (HTO) using single-photon emission computed tomography-computed tomography (SPECT-CT). We also sought to identify risk factors related to the presence of ELPS.

METHODS

This retrospective study included 150 patients (216 knees) who were candidates for HTO from an initial screening of 3579 patients (7158 knees). There were 183 female and 33 male knees with a mean age of 58 years. The presence of ELPS was defined as a grade 3 uptake on the SPECT-CT at the lateral PF joint. To determine the risk factors related to the ELPS, multivariate regression analysis was performed with independent demographic and radiographic variables.

RESULTS

Increased uptake on the lateral side of the PF joints was detected in 120 knees (56% of total subjects). Of these, 34 (16%) knees presented with a grade 3 uptake, which indicated the presence of ELPS. No single risk factor had significant associations with the presence of ELPS.

CONCLUSIONS

A considerable number of the knees that were candidates for HTO had ELPS. Nonetheless, we did not find any risk factor related to the presence of ELPS. These results suggest that surgeons should be cautious when diagnosing concomitant ELPS despite acceptable radiographic findings from patellofemoral joints when performing HTO.

Does the severity or cause of preoperative stiffness affect the clinical results and range of motion after total knee arthroplasty?

The purpose of this study was to assess the overall clinical results and range of motion (ROM) after total knee arthroplasty (TKA) in patients with preoperative stiffness. We also aimed to determine whether the severity or cause of the stiffness can affect the clinical outcome after surgery. This retrospective study included 122 knees (117 patients) with follow-up of more than 2 years (mean age, 64.3 years). TKA was performed using posterior-stabilized, varus-valgus constrained (VVC), and hinged prostheses. To determine the effect of the severity of stiffness on the clinical outcome, the subjects were divided into two groups: the severe group (preoperative ROM ≤ 50°; 18 knees) and the moderate group (preoperative ROM, 50°–90°; 104 knees). Then, clinical results and ROM were compared according to the severity or cause of preoperative stiffness. After surgery, preoperative ROM (mean, 78°; range, 25°- 90°) was improved (mean, 107°; range, 70°- 130°). The severe group more frequently used the VVC or hinged prostheses (72% vs. 18%). Furthermore, the severe group had worse knee and function scores as well as more complications (33% vs. 13%), even though the severe group had a greater ROM increment (47° vs. 27°) after surgery. Patients with osteoarthritis and rheumatoid arthritis showed better ROM and clinical results compared to patients with infectious or traumatic arthritis. Although TKA in stiff knees can be successful, the results are inferior in knees with severe stiffness and knees with infectious or traumatic arthritis.

Revision surgery for failed anterior cruciate ligament reconstruction with extension deficiency

BACKGROUND

Some patients with recurrent symptomatic instability after primary anterior cruciate ligament (ACL) reconstruction have an extension deficiency (ED). This study (a) compared preoperative clinical conditions between the ED and non-ED groups undergoing revision ACL reconstruction, (b) documented clinical and arthroscopic findings in ACL-reconstructed patients with reinstability and ED, and (c) determined whether the ED could be resolved and whether the clinical results of revision surgery differed between the ED and non-ED groups.

METHODS

This study included 58 patients who underwent revision ACL reconstruction. Patients were divided into the ED and non-ED groups. Preoperatively, the demographics and clinical conditions of the two groups were compared. Intraoperatively, the pathological structures that related to ED were documented. After surgery, the degree of postoperative ED and functional outcomes were compared between the two groups at 2-year follow-up.

RESULTS

The International Knee Documentation Committee subjective score and SF-36 physical component summary scores were worse in the ED group than the non-ED group preoperatively (54 vs 48 [P = 0.014]; 42 vs 39 [P = 0.031], respectively). Intraoperatively, the ED group showed significantly more frequent graft malposition (50% vs 5%), anvil osteophytes (44% vs 0%), and scarring around posterior intercondylar notch (100% vs 0%). However, there was no difference in the degree of postoperative ED and functional outcome between the two groups at follow-up.

CONCLUSIONS

ED in patients with recurrent instability after primary ACL reconstruction could be treated with good clinical result by addressing the pathological conditions causing ED in addition to ACL re-reconstruction.

Medial Tibial Periprosthetic Bone Resorption and Its Effect on Clinical Outcomes After Total Knee Arthroplasty: Cobalt-Chromium vs Titanium Implants

BACKGROUND

Recently, concerns arose over the medial tibial bone resorption of a novel cobalt-chromium implant. This study aimed at investigating the effects of tibial component material, design, and patient factors on periprosthetic bone resorption and at determining its association with clinical outcomes after total knee arthroplasty (TKA).

METHODS

A total of 462 primary TKAs using 5 types of implants were included. To evaluate tibial periprosthetic bone resorption, we assessed radiolucent lines and change in bone mineral density at the medial tibial condyle (BMD_MT). Factors related to bone resorption were assessed using regression analysis. Clinical outcomes were also evaluated with respect to periprosthetic bone resorption.

RESULTS

Compared to titanium implants, cobalt-chromium implants showed a higher incidence of complete radiolucent lines (23.1% vs 7.9% at 2 years post-TKA) and a greater degree of BMD_MT reduction. However, there was no significant difference between the implants made of the same material. Increased medial tibial bone resorption was associated with male sex, osteoporosis, larger preoperative varus deformity, longer follow-up period, and lower body mass index. The periprosthetic bone resorption was not associated with clinical outcomes including changes in range of motion and Western Ontario and McMaster Universities Osteoarthritis Index score. Furthermore, no cases warranted additional surgery.

CONCLUSION

Periprosthetic bone resorption was associated with implant material but not with implant design. Moreover, patient factors were related to the medial tibial bone resorption post-TKA. However, the periprosthetic bone resorption was not associated with short-term clinical outcomes. We contend that researchers should incorporate integrative considerations when developing and assessing novel implants.

Incidence of deep vein thrombosis before and after total knee arthroplasty without pharmacologic prophylaxis: a 128-row multidetector CT indirect venography study

Background

We sought to document the incidences of deep vein thrombosis (DVT) before and after total knee arthroplasty (TKA). In addition, we aimed to explor whether routine preoperative DVT evaluation was useful to establish DVT treatment strategies after TKA. Finally, we wanted to evaluate whether the incidences of DVT differed between patients undergoing unilateral and staged bilateral TKA within the same hospitalization period.

Methods

The retrospective study included 153 consecutive patients (253 knees) with osteoarthritis who underwent primary TKA. After surgery, mechanical compression devices (only) were used for DVT prophylaxis. DVT status before and after TKA was determined via 128-row, multidetector, computed tomography/indirect venography.

Results

Overall, the preoperative DVT incidence was 2.6% per patient and 1.6% per knee. All preoperative DVTs were distal in nature and asymptomatic. After TKA, newly developed thrombi were evident in various calf veins, without propagation of any pre-existing thrombi. Postoperatively, the overall incidences of DVT were 69.9% per patient and 58.5% per knee. The DVT incidences were 66% per patient and 69.8% per knee in the unilateral TKA group. In contrast, the incidences were 72% per patient and 55.5% per knee in the staged bilateral TKA group. There was one case of symptomatic distal (unilateral TKA; 0.65% per patient and 0.4% per knee) and proximal DVT (bilateral TKA; 0.65% per patient and 0.4% per knee), respectively.

Conclusions

The incidence of symptomatic DVT was low in Asian patients treated with mechanical compression devices alone, although substantial portion of patients had DVT after surgery. Routine preoperative DVT evaluation is probably not necessary; preoperative DVT was rare and of limited clinical relevance. Furthermore, staged bilateral TKA during a single period of hospitalization does not increase the incidence of DVT.

Two-stage approach to total knee arthroplasty using colistin-loaded articulating cement spacer for vancomycin-resistant Pseudomonas aeruginosa infection in an arthritic knee

BACKGROUND

A two-stage approach to total knee arthroplasty (TKA) using an antibiotic-impregnated articulating cement spacer is an option for an infected arthritic knee. Vancomycin combined with broad-spectrum antibiotics can be used to make an antibiotic-impregnated articulating cement spacer. Causative organisms are sometimes not confirmed before surgery. Joint infections of multidrug-resistant organisms are increasing. Therefore, routine combinations of antibiotics may not be effective.

METHODS AND RESULTS

We present a case of a patient who developed vancomycin-resistant Pseudomonas aeruginosa infection in an arthritic knee. A 71-year-old man was initially diagnosed with pyogenic arthritis caused by Staphylococcus aureus. He underwent arthroscopic debridement elsewhere. However, the infection persisted. He was referred to our hospital, and we performed a two-stage TKA using a vancomycin-based antibiotic-impregnated articulating cement spacer. Vancomycin-resistant P. aeruginosa was identified after surgery. Intravenous colistin was added. However, this failed, either because vancomycin was not effective against P. aeruginosa, or because insufficient systemic colistin due to colistin-induced acute kidney injury. Therefore, debridement was repeated, and colistin-loaded cement spacer was inserted. The spacer delivered high concentrations of colistin to the infected joint with decreased systemic effects. Thus, less systemic colistin was used. The infection was controlled without recurrent acute kidney injury. One year after surgery, conversion to TKA was successfully performed.

CONCLUSION

A two-stage approach to TKA using a colistin-loaded articulating cement spacer can be used for an arthritic knee infected by vancomycin-resistant P. aeruginosa. Furthermore, local administration of colistin using a cement spacer can reduce the systemic side effects of colistin.