Long-Term Outcomes of High-Flexion Design Total Knee Arthroplasty with a Short Posterior Flange.

Background: The purpose of this study was to evaluate the clinical and radiological outcomes of high-flexion total knee arthroplasty (TKA) using Vega Knee System (B. Braun, Aesculap) at a long-term follow-up and to analyze the implant survivorship. Methods: We enrolled 165 patients (232 knees) with a minimum 7-year follow-up after TKA (VEGA Knee System). For clinical assessment, range of motion (ROM), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) were used. For radiologic assessment, hip-knee-ankle angle, component position, and the existence of radiolucent lines and loosening were used. Survival analysis was conducted using the Kaplan-Meier method. Results: The mean follow-up period was 9.8 years. The mean ROM increased from 124.4° to 131.4° at the final follow-up. The WOMAC score decreased from 38.5 to 17.4 at the final follow-up (p < 0.001). All 5 subscales of the KOOS improved at the final follow-up (all subscales, p < 0.001). Revision TKA was performed in 10 cases (4.3%), which included 9 cases of aseptic loosing and 1 case of periprostatic joint infection. Of the 9 aseptic loosening cases (3.9%), 8 cases (3.4%) were loosening of the femoral component and 1 case (0.4%) was loosening of the tibial component. When revision for any reason was considered an endpoint, the 10-year survivorship was 96.2% (95% confidence interval [CI], 93.9%-98.5%). On the other hand, when revision for aseptic loosening was considered the endpoint, the 10-year survivorship was 96.6% (95% CI, 94.4%-98.8%). Conclusions: The Vega Knee System provided good clinical results in the long-term follow-up period. Although the VEGA Knee System showed acceptable implant survivorship, loosening of the femoral component occurred in about 3.4% of the patients. For more accurate evaluation of the survivorship of high-flexion design TKA with a short posterior flange, it is necessary to conduct more long-term follow-up studies targeting diverse races, especially Asians who frequently perform high-flexion activities.

Longer peripheral-track lesions are associated with instability after arthroscopic Bankart repair.

BACKGROUND: The glenoid track concept has enabled the categorization of Hill-Sachs lesions (HSLs) into on-track lesions and off-track lesions. Furthermore, among the on-track lesions, further categorization has been established based on the distance from the medial edge of the Hill-Sachs lesion to the medial edge of the glenoid track, into peripheral-track lesions and central-track lesions. Recent studies on peripheral-track lesions and central-track lesions within the glenoid track have shown inconsistencies in failure rates, which deserves further investigation. METHODS: A retrospective cohort comparison of patients who underwent arthroscopic Bankart repair between 2015 and 2020 was performed. 102 patients with peripheral-track HSLs were included. The patients were divided into 2 groups based on the results of the postoperative apprehension test: the apprehension positive group (n = 30), and the apprehension negative group (n = 72). Using preoperative computed tomography (CT) and an image reconstruction program, 3-dimensional (3D) images were segmented to calculate the length, width, depth, and distance of the HSLs. A multivariate logistic regression was used to determine the risk factors of recurrence, for which odds ratio (OR) and 95% confidence interval (CI) were provided. RESULTS: A multivariate logistic regression analysis revealed that the length of the peripheral-track HSLs was a significant independent predictor of failure in this study. (OR 1.380; 95% CI 1.170-1.627; P < .001). The receiver operating characteristics curve (ROC) demonstrated a predictive power (area under the curve = 0.841) and a threshold value of 14.2 mm. CONCLUSION: Length was the only risk factor for the recurrent instability of peripheral-track HSLs after ABR. In the context of surgical decision-making, utilizing the glenoid track concept, medical practitioners may need to evaluate instability by considering the length as a continuous factor, while differentiating between peripheral-track and central-track classifications.

Type of medial meniscus tear does not affect the clinical and radiological outcomes of medial opening-wedge high tibial osteotomy.

PURPOSE: The current study aimed to evaluate the effect of medial meniscus posterior root tear (MMPRT) on radiological and clinical outcomes after medial opening-wedge high tibial osteotomy (MOWHTO). METHODS: This retrospective cohort study included patients who underwent MOWHTO (113 knees) at our hospital between September 2012 and June 2020 and who were followed up for > 2 years. The radiological and clinical outcomes were compared between the MMPRT group (52 knees), who included patients with MMPRT, and the non-MMPRT group (61 knees), who comprised patients without meniscal tear or with any type of meniscal tear other than MMPRT. Logistic regression analysis was performed to evaluate factors affecting osteoarthritis (OA) progression after MOWHTO. RESULTS: The mean follow-up period was 40.6 ± 14.2 months. The mean ages of the MMPRT and non-MMPRT groups were 56.9 ± 6.4 and 54.4 ± 6.1 years, respectively (p = 0.031). There was no significant difference in the last follow-up radiological and clinical outcomes between the two groups. In the logistic regression analysis, the postoperative hip-knee-ankle angle was a risk factor of OA progression after MOWHTO (odds ratio 0.7; 95% confidence interval 0.5-0.9; p = 0.006), and the type of medial meniscus tear was not associated with OA progression (p = n.s.). CONCLUSIONS: In the short- to mid-term follow-up of MOWHTO, the radiological or clinical outcomes of patients with MMPRT were not inferior to those of patients without MMPRT. Postoperative lower extremity alignment, but not MMPRT, was a factor influencing MOWHTO prognosis. Concurrent root repair in HTO will restore the anatomy better; however, its effect on progression of OA is yet to be proven. LEVEL OF EVIDENCE: IV.

Risk of Infection After Septic and Aseptic Revision Total Knee Arthroplasty: A Systematic Review.

BACKGROUND: The causes of primary total knee arthroplasty (TKA) failure can be divided into septic and aseptic etiologies. It is unclear whether the etiology affects the infection rate after revision TKA. This systematic review was conducted to evaluate whether there is a difference in infection rates between septic and aseptic revision TKA. We hypothesized that infection rates would be higher after septic revision TKA. METHODS: The PubMed and Embase databases and the Cochrane Library were searched to find studies evaluating infection rates following septic and aseptic revision TKA. We included studies that compared the postoperative infection rates of a group that received revision TKA for aseptic failure and a group that received 1- or 2-stage revision TKA for septic failure. Studies on re-revision TKA and on revision surgery after partial knee arthroplasty were excluded, as were studies of debridement, antibiotics, and implant retention (DAIR). RESULTS: Twelve studies were included in this systematic review. In studies in which 1- or 2-stage revision TKA was performed for septic failure, septic revision TKA had a significantly higher infection rate than aseptic revision TKA (odds ratio [OR], 6.83; 95% confidence interval [CI], 1.54 to 30.33; p = 0.01). Similarly, in studies in which 2-stage revision TKA was performed for septic failure, septic revision TKA had a significantly higher infection rate than aseptic revision TKA (OR, 4.14; 95% CI, 2.33 to 7.36; p < 0.00001). In the comparison of revision TKA for aseptic loosening and septic revision TKA, septic revision TKA had a higher infection rate than aseptic revision TKA (OR, 4.45; 95% CI, 2.28 to 8.70; p < 0.0001). CONCLUSIONS: Overall, septic revision TKA had a higher infection rate than aseptic revision TKA. Even when 2-stage revision TKA was performed for septic failure, the infection rate was higher after septic revision TKA than after aseptic revision. Surgeons should explain the relatively high infection rates to patients undergoing revision TKA for septic failure of their primary joint replacement. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Factors affecting range of motion following two-stage revision arthroplasty for chronic periprosthetic knee infection.

INTRODUCTION: The purpose of this study was to evaluate factors that affect range of motion (ROM) following two-stage revision arthroplasty as a treatment for chronic periprosthetic knee infection. MATERIALS AND METHODS: A total of 98 patients diagnosed with chronic periprosthetic joint infection (PJI) following primary total knee arthroplasty between January 2009 and December 2019 and then underwent two-stage revision arthroplasty were reviewed retrospectively. Multiple regression analysis was performed to evaluate the factors that affect ROM after two-stage revision arthroplasty. ROM after two-stage revision arthroplasty was used as a dependent variable, while age at the time of surgery, ROM at PJI diagnosis, ROM after the first-stage surgery, the interval between the first-stage surgery and the second-stage surgery, whether a re-operation was performed before the second-stage surgery, culture results (culture negative or culture positive), and body mass index (BMI) were used as independent variables. RESULTS: Multiple regression analysis (R2 = 0.843) revealed that among the independent variables, ROM (ß = 0.604, P < 0.001) after the first-stage surgery, whether a re-operation was performed before the second-stage surgery (ß = - 8.847, P < 0.001), the interval between the first-stage surgery and the second-stage surgery (ß = - 0.778, P = 0.003), and BMI (ß = - 0.698, P = 0.041) were associated with ROM after two-stage revision arthroplasty, the dependent variable. CONCLUSIONS: In two-stage revision arthroplasty for chronic periprosthetic knee infection, ROM after the first-stage surgery, whether a re-operation was performed before the second-stage surgery, the interval between the first-stage surgery and the second-stage surgery, and BMI were found to be factors that were associated with ROM after two-stage revision arthroplasty.

Clinical outcomes of two-stage revision for chronic periprosthetic joint infection of the knee: culture-negative versus culture-positive.

BACKGROUND: The effect of negative culture on the treatment outcomes of chronic periprosthetic joint infection (PJI) is still controversial. The purpose of this study is to evaluate whether the outcomes of two-stage revision in culture-negative chronic PJI differ from those in culture-positive PJI. METHODS: The patients who received two-stage revisions due to chronic PJI during the period between 2007 and 2017 were retrospectively reviewed. The culture-negative and culture-positive PJI group included 57 cases and 79 cases, respectively. The demographic data, as well as reoperation, mortality, reinfection, and failure rates of each group were evaluated. RESULTS: There was a significant difference in reoperation rate between the two groups for the period from the first-stage surgery to the second-stage revision arthroplasty (p = 0.045). The reoperation rate of the culture-positive group was 25.3% (20/79) whereas that of the culture-negative group was 10.5% (6/57). Among the 136 PJI cases, 97 cases (71.3%) received reimplantation surgery (culture-negative group, 43 cases; culture-positive group, 54 cases). No significant difference was noted between the culture-negative and culture-positive groups with respect to the number of cases that did not undergo reimplantation surgery and the reoperation, reinfection, mortality, and failure rates after two-stage surgery (p > 0.05, all parameters). CONCLUSIONS: The culture outcome had no significant effect on the outcome of the two-stage revision in patients with chronic PJI. The reoperation rate after first-stage surgery was significantly higher in the culture-positive group, but the overall failure rate did not significantly differ in both the groups. The presence of a negative culture might be a good prognostic factor for chronic PJI.

Second-look arthroscopic findings and clinical outcomes after management of intra-articular lesions in acute ankle fractures with arthroscopy.

BACKGROUND: Anatomically surgical reduction of ankle fractures does not always result in a clinically favorable outcome. Arthroscopic examination combined with treatment of intra-articular lesion may related to clinical outcomes OBJECTIVES: The purpose of the present study was to review initial and second look arthroscopic finding of acute ankle fracture and to evaluate clinical outcomes. RESULTS: Lauge-Hansen classification system of ankle fractures included supination-external rotation type (n = 24), supination-adduction type (n = 3), pronation-external rotation type (n = 7), and pronation-abduction type (n = 6), total 40 ankles. Osteochondral lesions were found in 25 ankles (62%) with an initial arthroscopic finding of acute ankle fracture. Newly discovered chondral lesions in secondary arthroscopy were found in 17 cases. According to the Ferkel and Cheng staging at secondary arthroscopy, 4 of 25 ankles with osteochondral lesions of the talus were deteriorating (more than stage D). In terms of ICRS overall repair grades, 5 ankles (20%) were abnormal (grade III). Diffuse synovitis and arthrofibrosis were found in 12 and 7 ankles, respectively, in secondary arthroscopy, and correlations were found between AOFAS scores, VAS and intra-articular lesions. CONCLUSION: Second-look arthroscopic examination combined with treatment of intra-articular lesion such as arthrofibrosis and osteochondral lesion arising from ankle fracture surgery may consider to improve clinical outcomes.

Peroneal Tendon Subluxation and Dislocation in Calcaneus Fractures.

The present study investigated the relationship between type of calcaneal fractures and subluxation or dislocation of peroneal tendon. Also, we investigated clinical outcomes of patients with both calcaneal fractures and dislocations or subluxations of peroneal tendons in early surgical treatments (at the time of surgery for calcaneal fractures) and delayed surgical treatment (at the time of surgery for calcaneal plate removal) for dislocations or subluxations of peroneal tendons. We included 151 patients with calcaneal fractures who were followed for ≥2 years after surgery. Among them, 21 cases (13.9%) required reduction for peroneal tendon subluxation or dislocation. Reductions of peroneal tendons were performed at the time of surgery for calcaneal fractures in 11 cases, whereas the other 10 cases were performed during surgery for calcaneal implant removal. As classified by Essex-Lopresti, 94 cases (62.3%) were joint depression type and 17 (18.1%) were accompanied by dislocations or subluxations of peroneal tendons, whereas 57 (37.7%) were tongue type and 4 (7.0%) were accompanied by dislocations or subluxations of peroneal tendons. As classified by the Sanders system, 96 cases (63.6%) were Sanders A fracture lines, and 18 (18.8%) were accompanied by dislocations or subluxations of peroneal tendons. In 55 cases (36.4%) without Sanders A fracture lines, 3 (5.5%) were accompanied by dislocations or subluxations of peroneal tendons. In conclusion, calcaneal fractures with peroneal tendon dislocations are more common in joint depression type and Sander A type. Also, after a ≥2-year follow-up period, there were no significant differences in visual analog scale or foot and ankle outcome score whether reduction of peroneal tendons was done with reduction of fracture or removal of implant of calcaneus.

Extrusions do not affect degenerative morphologic changes in lateral meniscus allografts during midterm follow-ups.

PURPOSE: To investigate degenerative morphological changes in meniscus allograft after lateral meniscus allograft transplantation (MAT) based on extrusions. METHODS: Ninety-one patients who underwent lateral MAT were divided into extruded and non-extruded groups. Serial magnetic resonance imaging scans obtained 6 weeks, 1 year, and at the last follow-up (midterm, 3-7 years) post-surgery were evaluated retrospectively. Degenerative morphological changes at each time point in each group were compared using the postoperative meniscal width, thickness, and intrameniscal signal intensity (IMSI) at the anterior horn, mid-body, and posterior horn. The Lysholm scores and meniscal tears based on graft extrusion were also investigated. RESULTS: The mean age was 33.7 ± 11.1 years (64 men and 27 women). Fifty-three (58%) and 38 knees (42%) were classified into the non-extruded and extruded groups, respectively. The overall meniscal width of the mid-body decreased from 9.6 ± 1.3 to 6.5 ± 1.2 mm (p < 0.01), and IMSI of mid-body was increased from 1.2 ± 0.1 to 1.7 ± 0.1 (p < 0.01) during midterm follow-ups. No significant differences were observed between the meniscal width, thickness, and IMSI at the anterior horn (n.s.), mid-body (n.s.), and posterior horn (n.s.) of the two groups during the midterm follow-ups. The incidence of meniscus tears and Lysholm scores did not differ significantly between the groups during midterm follow-ups. CONCLUSION: The overall meniscus width of mid-body decreased while the relative IMSI of mid-body increased during midterm follow-ups after lateral MAT. Meniscal allograft extrusions did not influence postoperative changes in meniscus width, thickness, and relative intrameniscal signal intensity. LEVEL OF EVIDENCE: Level III.

Effect of chronic kidney disease on outcomes of total joint arthroplasty: a meta-analysis.

BACKGROUND: This meta-analysis was conducted to evaluate the differences in preoperative comorbidities, postoperative mortality, the rate of periprosthetic joint infection (PJI), and revision rate after total joint arthroplasty (TJA) between patients with chronic kidney disease (CKD)(CKD group) and patients with normal kidney function (non-CKD group). METHODS: We searched MEDLINE, EMBASE, and the Cochrane Library for studies assessing the effect of CKD on TJA outcome. This meta-analysis included studies that (1) compared the outcomes of TJA between the CKD and non-CKD groups; (2) compared the outcomes of TJA based on CKD stage; and (3) evaluated the risk factors for morbidity or mortality after TJA. We compared the mortality, PJI, and revision rate between CKD and non-CKD groups, and between dialysis-dependent patients (dialysis group) and non-dialysis-dependent patients (non-dialysis group). RESULTS: Eighteen studies were included in this meta-analysis. In most studies that assessed preoperative comorbidities, the number and severity of preoperative comorbidities were reported to be higher in the CKD group than in the non-CKD group. The risk of mortality was found to be higher in the CKD and dialysis groups compared with the respective control groups. In the studies based on administrative data, the unadjusted odds ratio (OR) of PJI was significantly higher in the CKD group than in the non-CKD group; however, no significant difference between the groups was noted in the adjusted OR. After total hip arthroplasty (THA), the risk of PJI was higher in the dialysis group than in the non-dialysis group. No significant difference was noted between the groups in the rate of PJI following total knee arthroplasty. The revision rate did not significantly differ between the CKD and non-CKD groups in the studies that were based on administrative data. However, the unadjusted OR was significantly higher in the dialysis group than in the non-dialysis group. CONCLUSIONS: Preoperative comorbidities and mortality risk were higher in the CKD and dialysis groups than in their respective control groups. The risk of revision was greater in the dialysis group than in the non-dialysis group, and the risk of PJI in the dialysis group became even greater after THA. Surgeons should perform careful preoperative risk stratification and optimization for patients with CKD scheduled to undergo TJA.

The effect of patellar facet angle on patellofemoral alignment and arthritis progression in posterior-stabilized total knee arthroplasty without patellar resurfacing.

BACKGROUND: The purpose of this study was to evaluate the effect of patellar facet angle on pre- and postoperative patellofemoral alignment and the progress of arthritis of the patellofemoral joint in posterior-stabilized total knee arthroplasty (PS TKA) without patellar resurfacing. METHODS: Patients who had a PS TKA for a varus osteoarthritic knee who were followed up for more than 2 years were included in this study. The radiologic and clinical outcomes were compared between 72 knees (group A) whose patellar facet angle was greater than 126° (> 126°) and 32 knees (group B) whose patellar facet angle was smaller than or equal to 126° (≤ 126°). For the radiologic assessment, the Kellgren-Lawrence grade, mechanical femorotibial angle, Insall-Salvati ratio, patellar tilt angle, patellar displacement and the osteosclerosis of the patellar ridge were evaluated. The range of motion (ROM) and patient-reported outcomes (the Knee Society knee score, the Knee Society function score, the Feller patellar score, and the Kujala patellofemoral score) were used for the clinical assessment. RESULTS: The preoperative patellar tilt angle was 9.8° (standard deviation [SD] 5.5) and 14.6° (SD 4.1) in group A and group B, respectively, a significant difference (p < 0.001). Other preoperative radiologic parameters and preoperative patient-reported outcomes and ROM showed no significant difference between the two groups (all parameters (p > 0.05). At the last-follow-up, 22 knees (30.6%) showed progression of osteosclerosis of the patellar ridge in group A and 13 knees (40.6%) showed progression of osteosclerosis in group B (p = 0.371). The postoperative radiologic and clinical outcomes showed no significant difference between the two groups (all parameters, p > 0.05). CONCLUSIONS: Although a narrow patellar facet angle was related to an increase of lateral tilting of the patella, it showed no impact on the preoperative clinical assessment. The radiologic and clinical outcomes evaluated after the PS TKA showed no statistical difference according to the patellar shape. Although the patellar shape evaluated by the patellar facet angle can partially affect the preoperative patellofemoral alignment, this study result indicated insignificant clinical relevance of the patellar shape in the PS TKA.

Influence of Glenoid Labral Bumper Height and Capsular Volume on Clinical Outcomes After Arthroscopic Bankart Repair as Assessed With Serial CT Arthrogram: Can Anterior-Inferior Volume Fraction Be a Prognostic Factor?

BACKGROUND: Arthroscopic labral repair combined with capsular plication decreases joint volume and restores glenoid labral bumper height; thus, the procedure helps decrease capsular redundancy. However, the decreased volume and restored glenoid labral bumper height could change over time, which could influence the outcome of the operation. PURPOSE: To (1) measure glenoid labral bumper height and capsular volume quantitatively in serial computed tomography arthrography (CTA) and evaluate the relationship between bumper height and joint volume and (2) compare the difference in bumper height and joint volume between groups with and without apprehension after arthroscopic Bankart repair. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Patients who had undergone arthroscopic Bankart repair between January 2012 and June 2016, and were assessed by CTA 3 to 6 months and 12 to 18 months after the operation were included. An image reconstruction program (3-dimensional slicer) was used to calculate inferior, anterior-inferior, and posterior-inferior joint volumes; the ratio of the anterior-inferior volume to the inferior volume was defined as the anterior-inferior volume fraction (VFAI). We also measured glenoid labral bumper height at the 5-, 4-, and 3-o'clock positions. RESULTS: A total of 50 patients were enrolled as study participants (mean age, 25.2 ± 9.29 years). Of these, 10 patients had either redislocation or apprehension, and 40 patients had neither. A significant correlation was observed between 5-o'clock glenoid labral bumper height and VFAI on early CTA (3-6 months) and late CTA (12-18 months) (early CTA: Pearson coefficient, -0.335, P = .040; late CTA: Pearson coefficient, -0.468, P = .003). VFAI at the early CTA was 42.20 ± 10.15 in the group with apprehension and 33.49 ± 9.66 in the group without apprehension; a significant difference was observed. VFAI at the late CTA was 45.84 ± 11.97 in the group with apprehension and 37.65 ± 9.70 in the group without apprehension and thus showed a significant difference between the 2 groups. However, the 3-, 4-, and 5-o'clock glenoid labral bumper heights on early and late CTAs did not show a statistically significant difference between the 2 groups. CONCLUSION: Early postoperative VFAI is related to postoperative apprehension and redislocation and might be reduced by increasing the 5-o'clock glenoid labral bumper height.

Influence of Varus Alignment on Survivorship After Lateral Meniscal Allograft Transplantation.

BACKGROUND: Factors associated with graft survival after lateral meniscal allograft transplantation (MAT) have not been fully determined, and survival analysis focused on effect of varus alignment has not been performed. HYPOTHESIS: Varus alignment of the knee leads to better graft survival and clinical outcomes after lateral MAT than normal alignment. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: The records of 204 consecutive patients who underwent lateral MAT were reviewed. After exclusion of cases undergoing revision MAT, cases without hip-knee-ankle standing radiographs, and cases with valgus alignment, the patients were categorized into 2 groups, those with normal alignment within -3° to 3° of the mechanical axis and those with varus alignment >3°. Cumulative graft survival rates were compared in the 2 groups before and after controlling for other covariates, including sex, age, body mass index (BMI), time from meniscectomy, the number of accompanying procedures, and cartilage status. Failure was defined as (1) a graft tear involving >50% or unstable peripheral rim of the allograft; (2) a Lysholm score <65 that was not improved afterward; (3) meniscectomy >50% or to the zone of meniscocapsular junction; or (4) conversion to revision MAT, realignment osteotomy, or arthroplasty. Clinical outcomes were compared between the 2 groups by Lysholm score. RESULTS: Of the 190 patients, 149 showed normal alignment of 0.3° ± 1.3° (range, -3° to 3°) and 41 showed varus alignment of 4.8° ± 0.6° (range, 4°-8°). A total of 22 patients (11.6%) experienced MAT failure: 21 patients with normal alignment and 1 with varus alignment. Kaplan-Meier survival analysis showed a significant difference in the cumulative graft survival rates between the 2 groups (log-rank test, P = .001). After controlling for age, sex, BMI, time from meniscectomy, the number of accompanying procedures, and cartilage status, varus alignment was found to be a significant protective factor (P = .004). On the other hand, there was no difference in clinical improvement measured by the Lysholm score between the 2 groups (P = .651). CONCLUSION: Varus alignment was associated with better graft survival after lateral MAT than normal alignment. However, no significant differences in clinical outcomes were observed.

The Effects of Surgical Technique in Total Knee Arthroplasty for Varus Osteoarthritic Knee on the Rotational Alignment of Femoral Component: Gap Balancing Technique versus Measured Resection Technique.

Few studies have compared the accuracy of femoral component rotation in the measured resection technique according to the preoperative computed tomography (CT) and gap balancing technique. The aim of this study was to evaluate whether there is a difference in accuracy and outlier incidence of femoral component rotation between gap balancing and measured resection techniques with or without preoperative CT and to evaluate the difference in patellofemoral alignment on simple radiographs and clinical outcomes. In this retrospective study, we evaluated femoral component rotation angle on the clinical and surgical transepicondylar axis (FCRA-cTEA and FCRA-sTEA, respectively), patellar tilt angle, lateral patellar displacement, and patient-reported outcomes in the gap balancing technique (Group 1) and in the measured resection technique without (Group 2) and with (Group 3) preoperative CT. A total of 163 total knee arthoplasty (TKA) replacements were included in this study. Average FCRA-cTEA was -3.4 ± 2.6, -2.8 ± 2.1, and -1.8 ± 2.3 degrees in groups 1 to 3, respectively (p = 0.002). Average FCRA-sTEA was -0.2 ± 2.7, 0.5 ± 2.4, and 1.5 ± 2.1 degrees, respectively (p = 0.001). In an outlier analysis that evaluated femoral component rotation using cTEA as reference, no significant difference was observed between the three groups (40.8, 37.3, and 23.7%, respectively, p = 0.133). When sTEA was used as a reference, groups 1 and 3 showed an outlier incidence of 8.2 and 8.5%, respectively, whereas this incidence was as high as 23.5% in group 2 (p = 0.030). No statistically significant group difference in patellofemoral alignment and patient-reported outcome was observed. In the measured resection technique with preoperative CT, the femoral component was externally rotated approximately 1 degree more than in the gap balancing or measured resection technique without preoperative CT. However, the difference in FCRA among the three techniques was not linked to the difference in patellofemoral alignment or patient-reported outcomes.

Clinical outcomes of two-stage total knee arthroplasty using articulating cement spacer in patients with infected arthritic knee: A comparison with arthroscopic surgery.

BACKGROUND: The aim of this study was to compare the functional outcomes and recurrence rate of infection between patients who underwent arthroscopic surgery and two-stage total knee arthroplasty (TKA) for infected arthritic knees. METHODS: A retrospective analysis was conducted on 52 patients (52 knees) with advanced knee joint arthritis who underwent arthroscopic surgery or two-stage TKA using articulating cement spacer (ACS) for knee joint infection between January 2009 and November 2013. Of the 52 patients (52 knees), 38 and 14 patients underwent arthroscopic surgery (AS group) and two-stage TKA using ACS (ACS-TKA group), respectively. Patient-reported outcomes (Knee Injury and Osteoarthritis Outcome Score (KOOS) and EuroQol-Visual Analog Scales (EQ-VAS)); range of motion; and recurrence rate of infection were evaluated. RESULTS: Recurrence of infection was observed in 7/38 patients who underwent arthroscopic surgery, all of whom received two-stage TKA using ACS. Regarding the functional outcomes of the ACS-TKA group obtained before conversion to TKA and those of the AS group obtained six months after arthroscopic surgery, the former group had better outcomes for KOOS pain, KOOS activities of daily living, KOOS quality of life, and EQ-VAS. Regarding the functional outcomes of the ACS-TKA group obtained during the last follow-up and after conversion to TKA and those of the AS group who underwent TKA after arthroscopic surgery, no significant between-group differences were observed. The infection recurrence rate was higher in the AS than in the ACS-TKA group. CONCLUSIONS: Considering infection control and functional outcomes, two-stage TKA using ACS can be an effective alternative treatment for patients with infected arthritic knees.

Second-look arthroscopic findings and clinical outcomes of meniscal repair with concomitant anterior cruciate ligament reconstruction: comparison of suture and meniscus fixation device.

INTRODUCTION: The purpose of this study was to evaluate the healing rate of repaired meniscus and functional outcomes of patients who received all-inside meniscal repair using sutures or devices with concomitant arthroscopic anterior cruciate ligament (ACL) reconstruction. MATERIALS AND METHODS: Among the patients who have ACL tear and posterior horn tear of medial or lateral meniscus, 61 knees who received all-inside repair using sutures (suture group, n = 28) or meniscal fixation devices (device group, n = 33) with concomitant ACL reconstruction during the period from January 2012 to December 2015, followed by second-look arthroscopy, were retrospectively reviewed. Healing status of the repair site was assessed by second-look arthroscopy. Through the clinical assessment, clinical success (negative medial joint line tenderness, no history of locking or recurrent effusion, and negative McMurray test) rate of the repaired meniscus and functional outcomes (International Knee Documentation Committee subjective score and Lysholm knee score) was evaluated. RESULTS: In a comparison of healing status of repaired meniscus evaluated by second-look arthroscopy, suture group had 23 cases of complete healing (82.1%), 4 cases of incomplete healing (14.3%), and 1 case of failure (3.6%). Device group had 18 cases of complete healing (54.5%), 4 cases of incomplete healing (24.2%), and 7 cases of failure (21.2%) (p = 0.048). Clinical success rate of the meniscal repair was 89.3% (25 cases) and 81.8% (27 cases) in suture group and device group, respectively (p = 0.488). No significant difference of functional outcomes was observed between the two groups (p > 0.05, both parameters). CONCLUSIONS: Among the patients who received meniscal repair with concomitant ACL reconstruction, suture group showed better healing status of repaired meniscus based on the second-look arthroscopy than device group. However, no significant between-group difference of clinical success rate and functional outcomes was observed.

Intraoperative fluoroscopy reduces the variability in femoral tunnel placement during single-bundle anterior cruciate ligament reconstruction.

PURPOSE: To evaluate the effect of using intraoperative fluoroscopy on femoral and tibial tunnel positioning variability in single-bundle anterior cruciate ligament (ACL) reconstruction. METHODS: A total of 80 consecutive patients with single-bundle ACL reconstruction between 2014 and 2016 were retrospectively reviewed. Among them, 40 underwent ACL reconstruction without fluoroscopy (non-fluoroscopy group) and 40 underwent fluoroscopy-assisted ACL reconstruction (fluoroscopy group). Femoral and tibial tunnel locations were evaluated using a standardized grid system with three-dimensional computed tomography images. Femoral and tibial tunnel location variability was compared between the groups. RESULTS: The operation time was longer in the fluoroscopy group than in the non-fluoroscopy group (61.3 ± 5.2 min vs. 55.5 ± 4.5 min, p < 0.001). In the fluoroscopy group, a guide pin was repositioned in 16 (40%) cases on the femoral side and 2 (5%) cases on the tibial side. No significant difference in the femoral tunnel location was observed between the fluoroscopy and non-fluoroscopy groups (anterior-posterior plane, 29.0% ± 3.2% vs. 30.0% ± 6.1%; proximal-distal plane, 30.8% ± 4.8% vs. 29.4% ± 8.3%; all parameters, n.s.); variability was significantly lower in the fluoroscopy group (p < 0.001 for both anterior-posterior and proximal-distal planes). No significant difference in the tibial tunnel location and variability was observed between the fluoroscopy and non-fluoroscopy groups (medial-lateral plane, 45.8% ± 2.0% vs. 46.6% ± 2.4%; anterior-posterior plane, 31.2% ± 4.0% vs. 31.0% ± 5.4%) (all parameters, n.s.). CONCLUSIONS: Tunnel positioning with fluoroscopic assistance is feasible and effective in achieving consistency in femoral tunnel placement despite a slightly longer operation time. Intraoperative fluoroscopy can be helpful in cases wherein identifying anatomical landmarks on arthroscopy was difficult or for surgeons with less experience who performed ACL reconstruction. LEVEL OF EVIDENCE: IV.

A Comparison of Long-Term Outcomes of Computer-Navigated and Conventional Total Knee Arthroplasty: A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: It is not clear whether long-term outcomes differ between computer-navigated and conventional total knee arthroplasty. The purpose of this study was to perform a meta-analysis comparing the radiographic outcomes, the long-term functional outcomes, and survivorship between computer-navigated total knee arthroplasty and conventional total knee arthroplasty. METHODS: We searched MEDLINE, Embase, and the Cochrane Library to identify studies comparing long-term outcomes between computer-navigated total knee arthroplasty and conventional total knee arthroplasty. Randomized controlled trials with mean follow-up durations of >8 years were included. The meta-analysis compared radiographic outcomes (postoperative alignment), functional outcomes (range of motion and patient-reported outcomes), and survivorship of the 2 techniques. RESULTS: Nine studies were included. A meta-analysis of accuracy revealed better outcomes in computer-navigated total knee arthroplasty when compared with conventional total knee arthroplasty in terms of the sagittal alignment of the femoral component (risk ratio [RR], 0.69; [95% confidence interval (CI), 0.51 to 0.93]; p = 0.02) and the coronal alignment of the tibial component (RR, 0.75 [95% CI, 0.60 to 0.95]; p = 0.02). The mechanical axis of the lower extremity, the coronal alignment of the femoral component, and the sagittal alignment of the tibial component did not differ significantly between the 2 groups. The functional outcomes did not differ significantly between the 2 techniques. Both in terms of the revision rate and the incidence of aseptic loosening, there were no differences between the 2 techniques. CONCLUSIONS: Although computer-navigated total knee arthroplasty resulted in better outcomes in postoperative component alignment than conventional total knee arthroplasty, there were no significant differences in long-term functional outcomes and survivorship between the 2 techniques. To fully evaluate the utility of computer navigation in total knee arthroplasty, additional randomized controlled studies including diverse ethnic groups and countries, as well as studies evaluating the correlation between postoperative alignment and long-term survivorship, are necessary. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

A Magnetic Resonance Imaging Analysis of Shrinkage of Transplanted Fresh-Frozen Lateral Meniscal Allografts During a Minimum Follow-up of 8 Years.

PURPOSE: To evaluate the incidence and degree of shrinkage of transplanted fresh-frozen meniscal allografts in a long-term period of >8 years and to investigate whether the shrinkage of allograft progresses and is associated with inferior clinical and radiologic outcomes after meniscal allograft transplantation (MAT) in the long term. METHODS: Twenty-two knees were reviewed in 20 patients (mean age, 31.41 ± 9.11 years) who underwent isolated lateral MAT. All patients were followed with magnetic resonance imaging (MRI) for at least 8 years (mean, 11.78 ± 3.10 years). The allograft widths of the anterior horn, mid-body, and posterior horn at 1 and >8 years postoperatively were measured by using MRI. To estimate the degree of shrinkage, the relative changes in widths during intervals were calculated. Patients were categorized into 4 groups according to shrinkage degree: minimal (<10%), mild (10%-25%), moderate (25%-50%), and severe (>50%). The joint space width was measured on the weightbearing radiographs to evaluate the radiologic outcome. The Lysholm score was used to evaluate the clinical outcome. RESULTS: The relative change in the width of the anterior horn, mid-body, and posterior horn, compared with that 1 year postoperatively, was 82.7% (95% confidence interval 77.4%-87.5%), 75.9% (70.7%-81.0%), and 85.0% (81.4%-88.5%), respectively. The shrinkage degree was greater at the mid-body than at the anterior and posterior horns. About 70% of allografts showed ≥10% shrinkage of the posterior horn. Meniscal shrinkage did not show significant correlation with clinical and radiologic outcome. CONCLUSIONS: At long-term follow-up (>8 years), shrinkage of transplanted fresh-frozen meniscal allografts progressed at 1 year postoperative. On average, the shrinkage was mild and more prominent in the mid-body than in the anterior or posterior horn. In this study, it could not be concluded that the shrinkage of allografts was significantly associated with inferior clinical and radiologic outcomes in the long term. LEVEL OF EVIDENCE: Level IV, therapeutic case series.