Impact of implant positions in total knee arthroplasty on the postoperative knee kinematics of tibial rotation.

Introduction: In total knee arthroplasty (TKA), the implant positions and knee kinematics, as well as the manifestation of medial pivot motion, play pivotal roles in determining postoperative clinical outcomes. The purpose of the current study was to analyze the correlation between knee kinematics, which was measured during TKA and implant positions derived using computed tomography (CT) examination after TKA. Methods: This study comprised 64 patients (76 knees) who underwent primary TKA between 2015 and 2022. A navigation system was used in TKA procedures, and intraoperative knee kinematics were automatically calculated with it. Utilizing three-dimensional evaluation software, positioning of implants was quantified with CT images taken pre- and post-operatively. Multiple regression analyses were employed to explore the impact of femoral component position (FP) and tibial component position (TP) on knee kinematics, focusing on the extent of tibial rotational motion (TRM) during passive knee motion. Results: FP affected TRM between knee extension and 90° flexion (p = 0.003, 95 % confidence interval [CI]: 0.315-1.384) and between knee extension and full flexion (p = 0.0002, 95 % CI: 0.654-1.844) after TKA. FP in internal rotation positively affected internal TRM after TKA. TP was not associated with TRM. Conclusions: Findings of the current study suggest that FP in internal rotation positively impacts knee kinematics after TKA.

Impact of the sagittal spinopelvic and coronal lower extremity alignments on clinical outcomes after medial unicompartmental knee arthroplasty.

Introduction: We evaluated whether the clinical outcomes, including postoperative knee range of motion (ROM), after unicompartmental knee arthroplasty (UKA) were associated with the sagittal spinopelvic parameters and coronal alignment of the full lower extremity. Methods: Forty-two patients (50 knees: six men, seven knees; 36 women, 43 knees) who underwent medial UKA between April 2015 and December 2022 were included. Preoperative radiographic examinations of the index for sagittal spinopelvic alignment included the sagittal vertical axis (SVA), lumbar lordosis, sacral slope (SS), pelvic tilt (PT), and pelvic incidence. The anteroposterior hip-knee-ankle angle (HKAA) was calculated. The relationship of clinical outcomes and the risk of knee flexion angle ≤125° and knee flexion contracture ≥10° 1-year post-UKA with radiographic parameters were evaluated. Results: Preoperative HKA angle affected postoperative knee flexion angle ≤125° (p = 0.017, 95% confidence interval [CI]: 0.473-0.930) in logistic regression analysis. Patients with a knee flexion angle ≤125° had a higher preoperative HKAA (9.8 ± 3.0°), higher SVA (83.8 ± 37.0 mm), and lower SS (23.7 ± 9.0°) than those with a flexion angle >125° (preoperative HKAA: 6.6 ± 4.0°, SVA: 40.3 ± 46.5 mm, SS: 32.0 ± 6.3°) (p = 0.029, 0.012, and 0.004, respectively). PT related to postoperative knee flexion contracture ≥10° (p = 0.010, 95% CI: 0.770-0.965) in the logistic regression analysis. Patients with flexion contracture ≥10° had higher PT (35.0 ± 6.6°) and SVA (82.2 ± 40.5 mm) than those with flexion contracture <10° (PT, 19.3 ± 9.0°; SVA, 42.4 ± 46.5 mm) (p = 0.001 and 0.028, respectively). The postoperative clinical outcome was correlated with the postoperative knee flexion angle and SVA (p = 0.036 and 0.020, respectively). Conclusions: The preoperative HKAA affected postoperative knee flexion angle, and the knee flexion contracture and clinical outcomes post-UKA were associated with PT and SVA, respectively. To predict outcomes for knee ROM and clinical scores after UKA, radiographic examination, including the sagittal spinopelvic parameters and the coronal view of the full lower extremity, is essential.

Femoral trochlear groove cartilage damage after open-wedge high tibial osteotomy is associated with the change in patellar height relative to the femoral condyle.

BACKGROUND: Medial open-wedge high tibial osteotomy (OWHTO) is performed for isolated medial compartment osteoarthritis or osteonecrosis of the knee and correction of varus deformity of the full lower extremity. OWHTO may induce sagittal parameter changes, including these in the tibial posterior slope (TPS), patellar height (PH), and patellofemoral joint problems. This study aimed to identify radiographic parameters associated with patellofemoral cartilage damage after OWHTO. HYPOTHESIS: The patellofemoral joint cartilage worsens after OWHTO and is adversely affected by PH changes. PATIENTS AND METHODS: Twenty patients (25 knees) who underwent primary OWHTO and subsequent implant removal surgery, including second-look arthroscopy for evaluation of the patellofemoral cartilage condition were enrolled. The patients were received 12 to 35 months of postoperative follow-up, and categorized into two groups according to whether patellofemoral cartilage damage worsened. TPS and PH parameters, including the Insall-Salvati, Blackburne-Peel, Caton-Deschamps, and modified Blumensaat (MBI) indices, were measured on lateral knee radiographs. The hip-knee-ankle and medial proximal tibial angles were measured using an anteroposterior radiograph of the full lower extremity. The extent of change from preoperative to postoperative (Δ) was calculated for all indices. RESULTS: Eleven knees (44%) had worsening cartilage conditions in the femoral trochlear groove, with>1-degree of deterioration in the International Cartilage Repair Society grade. The radiographic measure for predicting patellofemoral cartilage deterioration was ΔMBI (95% confidence interval [CI]: 3.53×10-14-0.812, p=0.047). PF cartilage damage tended to progress in ΔMBI<-0.145. The postoperative TPS and HKAA in patients with deterioration in patellofemoral cartilage damage was greater than that in patients without deterioration in patellofemoral cartilage damage (p=0.037 and 0.038, respectively). DISCUSSION: The patellofemoral cartilage damage tends to progress after OWHTO. ΔMBI is a factor for predicting worsening patellofemoral cartilage condition. However, attention should be paid to the excessive posterior slope as high TPS and valgus alignment as valgus HKAA because intraoperative control of MBI is impossible. LEVEL OF EVIDENCE: IV, retrospective study.

Distribution of coronal plane alignment of the knee classification does not change as knee osteoarthritis progresses: a longitudinal study from the Toei study.

PURPOSE: The purpose of this study was to investigate the coronal plane alignment of the knee (CPAK) phenotypes of individuals with knee osteoarthritis (OA) progression. We hypothesized that distributions of CPAK phenotypes would be similar throughout OA progression, despite arithmetic hip-knee-ankle angle (aHKA) and joint line obliquity (JLO) changing. METHODS: A total of 248 patients (79 men and 169 women) participated in the first study in 2012 and the fifth study in 2020. Patients with progression of knee OA for eight years were included. Knee OA progression was defined as advancement from KL grade 0-2 to KL grade 3 or 4. Alignment parameters, including the aHKA, JLO, hip-knee-ankle angle (HKA), lateral distal femur angle (LDFA), medial proximal tibial angle (MPTA), and joint line convergence angle (JLCA), were measured. Changes in distribution of CPAK classifications and alignment parameters were investigated. Alignment parameters were compared using a paired t-test. Statistical significance was defined as p < 0.05. RESULTS: The study included 48 patients (60 knees). The distributions of all CPAK phenotypes were similar between 2012 and 2020. MPTA (83.7° ± 2.8° vs. 82.3° ± 4.8°, p < 0.01), aHKA (- 3.6° ± 3.8° vs. - 4.9° ± 6.2°, p = 0.01), and JLO (171.1° ± 4.6° vs. 169.5° ± 5.1°, p < 0.01) decreased significantly, and JLCA (1.17° ± 2.2° vs. 3.1° ± 4.7°, p < 0.01) and HKA (4.8° ± 3.9° vs. 8.0° ± 5.4°, p < 0.01) increased significantly. In contrast, LDFA (87.4° ± 3.2° vs. 87.2° ± 3.1°, p = n.s.) did not change significantly. CONCLUSIONS: The CPAK classification system can predict constitutional alignment, even with knee OA progression, and enables surgeons to perform individualized preoperative alignment planning according to knee phenotypes.

Usefulness of Force-Controlled Pelvic Stress Radiograph in the Evaluation and Treatment of Fragility Fractures of the Pelvis in Geriatric Patients: A Pilot Study.

This study aimed to investigate the usefulness of force-controlled pelvic stress radiographs in the evaluation and treatment of fragility fractures of the pelvis (FFP) using a functional treatment strategy. We conducted a retrospective study of 55 geriatric patients with FFP who underwent pelvic stress radiographs on admission. The differences in the sacral width, pelvic ring width, and medial femoral head width between the radiographs with and without the Sam Sling II M size were defined as Δ sacral width, Δ pelvic ring width, and Δ medial femoral head width, respectively. We used Pearson's correlation test to assess the relationship between the degree of radiographic instability and the Johns Hopkins highest level of mobility scale (JH-HLM) at 10-days postadmission. Conventional receiver-operating-characteristic curve analysis was used to identify cases requiring surgery using the best cutoff value for radiographic instability. The JH-HLM was significantly correlated with Δ sacral width (r=-0.401, p=0.017), but not with Δ pelvic ring width (r=-0.298, p=0.080) nor with Δ medial femoral head width (r= -0.261, p=0.128). The best cutoff value of Δ sacral width in identifying surgical cases was 10.7 mm (sensitivity 75.0%, specificity 98.0%). Force-controlled pelvic stress radiographs could be helpful in assessing the need for surgery on admission.

A systematic review regarding clinical characteristics, complications, and outcomes of surgical and non-surgical patients with fragility fracture of the pelvis.

We conducted this systematic review to clarify the clinical characteristics, complications, and outcomes of surgical and non-surgical patients with fragility fracture of the pelvis (FFP). We searched PubMed, Google Scholar, Cochrane Library, Web of Science, and MEDLINE for English language articles on FFP. We calculated pooled odds ratios (ORs) or mean differences (MDs) of surgical patients in comparison to non-surgical patients for clinical characteristics (Rommens FFP classification, age, sex, dementia, osteoporosis, diabetes mellitus, pulmonary disease, cardiovascular disease, and malignancy), complications (pneumonia, urinary tract infection, cardiac event, thrombosis, pulmonary embolism, pressure ulcer, multiple organ failure, anemia caused by surgical bleeding, and surgical site infection), and outcomes (hospital mortality and one-year mortality). Five studies involving 1,090 patients with FFP (surgical patients, n = 432; non-surgical patients, n = 658) were included. FFP type III and IV (OR = 8.44; 95% confidence interval [CI] 5.99 to 11.88; p<0.00001), a younger age (MD = -3.29; 95% CI -3.83 to -2.75; p<0.00001), the absence of dementia (OR = 0.36; 95% CI 0.23 to 0.57; p<0.0001), and the presence of osteoporosis (OR = 1.74; 95% CI 1.29 to 2.35; p = 0.0003) were significantly associated with the surgical patients. Urinary tract infection (OR = 2.06; 95% CI 1.37 to 3.10; p = 0.0005), anemia caused by surgical bleeding (OR = 4.55; 95% CI 1.95 to 10.62; p = 0.0005), and surgical site infection (OR = 16.74; 95% CI 3.05 to 91.87; p = 0.001) were significantly associated with the surgical patients. There were no significant differences in the outcomes between the surgical and non-surgical patients. Our findings may help to further understand the treatment strategy for FFP and improve clinical outcomes.

Relationship between the Femoral and Tibial Component Positions and Postoperative Knee Range of Motion after Posterior-Stabilized Total Knee Arthroplasty in Varus-Aligned Knees.

This study aimed to evaluate the relationship between the femoral and tibial component positions and postoperative knee range of motion after posterior-stabilized total knee arthroplasty (TKA). Forty-four patients (48 knees in total: 9 men, 9 knees; 35 women, 39 knees) who underwent posterior-stabilized TKA using a navigation system were included. The femoral and tibial component positions were measured from the preoperative and postoperative computed tomography data with three-dimensional evaluation software. We investigated the relationship between the knee range of motion, including extension restriction and maximum flexion angles at 2 years postoperatively, and the femoral and tibial component positions. Patients with knee extension restriction of 10° or more at 2 years postoperatively showed greater posterior flexion position of the tibial component than those with knee extension restriction less than 10° (6.2° and 3.9°, respectively, p=0.018). The postoperative knee flexion angle was positively associated with the internal rotational position of the femoral component (p=0.032, 95% confidence interval: 0.105-2.178). Patients with a knee flexion angle more than 120° at 2 years postoperatively had greater internal rotational position of the femoral component than those with 120° or less (5.2° and 1.5°, respectively, p=0.002). In conclusions, after posterior-stabilized TKA, the postoperative knee extension restriction angle was associated with the posterior flexion position of the tibial component, and the knee flexion angle was positively related to the internal rotational position of the femoral component.

Spinal Subdural Hematoma Migration From a Cranial Subdural Hematoma: Two Case Reports and Literature Review.

Spinal subdural hematoma (SSDH) associated with cranial subdural hematoma (CSDH) is considered extremely rare and the etiology remains unclear. Herein, we report two cases of spontaneous SSDH concomitant with CSDH, with no history of trauma. First, a healthy 35-year-old woman suffered from left leg pain following a headache caused by acute CSDH. Magnetic resonance imaging (MRI) of the lumbar spine showed SSDH extending from the L5 to S2 vertebral levels. The leg symptoms were gradually relieved with conservative treatments within two weeks after onset. The SSDH was completely resolved six months after onset on MRI evaluations. Next, a 69-year-old woman developed a headache and right hemiparesis. Brain computed tomography (CT) demonstrated chronic left-sided CSDH and she underwent a single burr-hole craniotomy. Three weeks after surgery, she experienced difficulty walking because of severe leg pain caused by SSDH extending from the L3 to S1. The clinical symptoms were completely resolved with conservative treatment within one month after onset. At 3 months follow-up, SSDH disappeared on MRI evaluation. Herein, we presented two cases of SSDH associated with CSDH. In both cases, the leg symptoms of SSDH developed following the onset of CSDH. Given that both patients remained active during the interval between CSDH onset and the appearance of SSDH symptoms, the SSDH was likely caused by migration of the CSDH contents to the lumbar spine because of gravity.

Predictors for clinical outcomes of tubular surgery for endoscopic decompression in selected patients with lumbar spinal stenosis.

INTRODUCTION: The success rate of decompression surgery for lumbar spinal stenosis (LSS) has been reported to vary from 60 to 80%. The purpose of this study was to analyze the predictors for clinical outcomes after tubular surgery for endoscopic decompression (microendoscopic decompression) for LSS. MATERIALS AND METHODS: A total of 100 patients with degenerative LSS (M/F: 61/39, Age: mean 69.7 years), who underwent microendoscopic decompression and had a minimum 2-year follow-up (FU) after surgery, were reviewed. All patients suffered from leg-related symptoms predominantly without severe mechanical back pain, preoperatively. The presence of chronic arterial occlusion of the lower limbs was ruled out. The primary outcome measure was clinical evaluation at 2-year FU using the Oswestry Disability Index (ODI). Furthermore, numeric rating scales, Japanese Orthopedic Association (JOA) lumbar score and JOA Back Pain Evaluation Questionnaire were used for secondary outcome measures. Based on findings of univariable analyses, multivariable logistic regression analysis was applied to identify preoperative predictors for the clinical outcomes. RESULTS: Sixty-eight patients (68%) were assessed as good outcomes, on the basis of minimum clinically important difference of the ODI (13 points ≤) and final ODI score (< 30 points). The secondary outcomes were further support for the primary outcome. In multivariable logistic regression analysis, co-existence of intradiscal vacuum phenomenon with LSS (odds ratio [OR] 8.26; 95% confidence interval [95% CI] 2.32-29.34; p = 0.001) and ischemic cardiovascular comorbidities (OR, 13.3; 95% CI, 1.9-92.57; p = 0.009) were significantly associated with poor clinical outcomes. CONCLUSIONS: We found co-existence of intradiscal vacuum phenomenon with LSS and ischemic cardiovascular comorbidity to be preoperative predictors of less favorable clinical outcomes after microendoscopic decompression in selected patients of LSS. Although the conclusion obtained from restricted state, the information would be able to help in patient selection of the tubular surgery for endoscopic decompression for LSS.

Comparison Between the Simultaneous Reconstructions of the Anterior Talofibular Ligament and Calcaneofibular Ligament and the Single Reconstruction of the Anterior Talofibular Ligament for the Treatment of Chronic Lateral Ankle Instability.

This study aimed to evaluate the procedures of reconstruction surgery for chronic lateral ankle instability. We compared single anterior talofibular ligament reconstruction to simultaneous reconstructions of the anterior talofibular and calcaneofibular ligaments. From 2015 to 2019, 14 consecutive patients diagnosed with chronic lateral ankle instability underwent arthroscopic anterior talofibular ligament reconstruction with or without calcaneofibular ligament reconstruction after conservative treatment. Seven patients underwent single anterior talofibular ligament reconstruction (group AT), and 7 patients underwent simultaneous reconstructions of the anterior talofibular ligament and calcaneofibular ligament (group AC). The Japanese Society for Surgery of the Foot scale scores and Karlsson scores significantly improved in all patients 1 year postoperatively. The radiographic measurement of the talar tilt angle and the talar anterior drawer distance at 1 year after surgery were also significantly improved compared to preoperative values. The postoperative talar tilt angle was significantly greater in group AT (median 6°, range 3°-7°) than that in group AC (median 3°, range 2°-5°; p = .038). The postoperative talar anterior drawer distance, Japanese Society for Surgery of the Foot scale score, and Karlsson score were not significantly different between the 2 groups. We found that although the clinical outcomes after the anterior talofibular ligament reconstruction with or without the calcaneofibular ligament reconstruction for chronic lateral ankle instability were good, instability of the talar tilt angle at 1 year postoperatively in patients who underwent single anterior talofibular ligament reconstruction was greater than that in patients who underwent simultaneous anterior talofibular and calcaneofibular ligament reconstructions.

Prognostic nutritional index as a risk factor for aseptic wound complications after total knee arthroplasty.

BACKGROUND: Patients with malnutrition have a high risk of postoperative complications in total knee arthroplasty (TKA). Previously, serum albumin and total lymphocyte count were considered preoperative nutritional assessment measures. Prognostic nutritional index (PNI) is calculated by a combination of serum albumin and total lymphocyte count. This study aimed to identify the risk factors for postoperative complications after TKA, including preoperative nutritional assessment, and evaluated preoperative PNI as a predictor of postoperative complications. METHODS: One-hundred and sixty patients (234 knees) who underwent primary TKA were enrolled consecutively from 2010 to 2018. The serum albumin (g/dL) and total lymphocyte count (/mm3) were examined within 3 months before TKA; thereafter, the PNI was calculated. Postoperative aseptic wound problems, such as skin erosion and dehiscence within 2 weeks and periprosthetic joint infection after TKA were examined. RESULTS: Periprosthetic joint infections occurred in 14 knees (6.0%). Postoperative aseptic wound problems within 2 weeks were significant risk factors of periprosthetic joint infection (odds ratio; 5.10, 95% confidence interval [CI]; 1.438-18.093, p = 0.012). No significant differences were noted in the patient demographics, such as age, sex, body mass index (BMI), and comorbidities between the positive and negative groups for periprosthetic joint infection, except for the rate of aseptic operative wound problems. Furthermore, postoperative aseptic wound problems were influenced by high BMI (odds ratio; 1.270, 95% CI; 1.111-1.453, p = 0.000) and low PNI (odds ratio; 0.858, 95% CI; 0.771-0.955, p = 0.015). CONCLUSIONS: Preoperative nutritional status, indicated by PNI and BMI, was associated with postoperative wound problems within 2 weeks. Periprosthetic joint infection after TKA was associated with early postoperative aseptic wound problems.

Functional treatment strategy for fragility fractures of the pelvis in geriatric patients.

PURPOSE: We propose a functional treatment strategy for fragility fractures of the pelvis (FFP) in geriatric patients; patients with such fractures normally undergo 10 days of conservative therapy with full-weight bearing within pain limits. Conservative therapy for FFP is continued for patients who can stand with assistance, and surgical stabilization is recommended for patients with difficulty in auxiliary standing at 10 day postadmission. This study aimed to compare the outcomes of functional treatment between geriatric patients with FFP type I/II and those with FFP type III/IV, as described by Rommens et al. METHODS: We conducted a retrospective study of 84 geriatric patients who underwent functional treatment for FFP. Based on the results of the first examination, the patients were allocated to the following FFP types: type I/II (n = 53) and type III/IV (n = 31). Change in functional mobility scale described by Graham et al. from before injury to the final follow-up were compared between the groups. RESULTS: There was no significant difference in the functional mobility scale (0.25 ± 0.70 vs. 0.23 ± 0.56, p = 0.889) between FFP type I/II and FFP type III/IV. CONCLUSION: The outcomes of the functional treatment for FFP for the geriatric patients did not differ significantly between the radiographic classifications. Functional treatment could, therefore, be a treatment option for almost all radiographic types of FFP, especially for geriatric patients. Further investigations are warranted.

Occipital bone erosion induced by C1 pedicle screw as a late complication of atlantoaxial fixation: a case report and literature review.

PURPOSE: The objective of this case report is to highlight occipital bone erosion as an unusual late complication of C1-C2 instrumented fixation. CASE PRESENTATION: A 60-year-old man of a displaced Anderson type II odontoid fracture was surgically treated by C1-C2 pedicle screw fixation. Occipital bone erosions, caused by a repeat irritation of the end of rod to the occipital bone, were detected on multiplane reconstructed computed tomography at 3 months after surgery. The lesion progressed over time with increasing the C2 anteversion on radiological evaluations. Eventually, the bony shell had been reactively formed around the protruded screw-rod construct and the Oc-C1 segment had been spontaneously stabilized. Fortunately, he had experienced no symptoms caused by the lesion at 5-year follow-up. CONCLUSION: The occipital bone erosion is an unusual late complication in C1-C2 posterior fixation using C1 pedicle screw. The increasing occipital-C1 lordosis compensating for the great C2 anteversion (high C2 slope) was related to the progression of the lesion. In C1-C2 pedicle screw fixation, surgeons should recognize a possibility of this complication and realize a relation between the occurrence of the lesion and the sagittal alignment of the cervical spine to take measures to avoid the complication.

Dependence of knee range of motion on the alignment of femoral and tibial components after medial unicompartmental knee arthroplasty.

INTRODUCTION: This study evaluated the relationship between postoperative knee flexion angles and the position of femoral and tibial components in unicompartmental knee arthroplasty (UKA). MATERIALS AND METHODS: Eighteen patients (a total of 22 knees: three men, four knees; 15 females, 18 knees) who underwent navigation-assisted UKA were included. Pre- and postoperative computed tomography images were applied on 3D software, which were matched and used to calculate the position of femoral and tibial components. Correspondingly, we investigated the relationship between the knee range of motion (ROM) at 1-year postoperative follow-up and the position of femoral and tibial components. RESULTS: At 1-year post-UKA, the knee flexion angle was associated with the posterior flexion angle of tibial components. This particular angle was significantly greater in the group with equal or greater postoperative knee ROM compared to preoperative ROM (5.2 ± 2.1°) than in the group with less postoperative knee ROM compared to preoperative ROM (2.6 ± 1.6°, p < 0.01). There was no significant difference between both groups in the femoral component position, preoperative posterior slope of the medial tibial plateau, change in the pre- to postoperative posterior tibial slope, and postoperative knee society score. CONCLUSION: The posterior flexion angle of the tibial component affected the improvement/deterioration of the postsurgery knee flexion angle in navigation-assisted UKA. For improved outcomes after UKA using navigation systems, surgeons should aim to achieve a 5° to 8° posterior flexion angle of the tibial component.

Association of knee flexion angle after posterior-stabilized total knee arthroplasty with postoperative tibial external position relative to the femur and the extent of tibial internal rotation from knee extension to flexion.

BACKGROUND: This study evaluated the relationship between preoperative and postoperative knee kinematics, moreover, investigated tibial rotational position and the extent of tibial internal rotation from knee extension to flexion as factors to obtain significant knee flexion after total knee arthroplasty (TKA). METHODS: Fifty-four patients (60 knees total; 15 males, 16 knees; 39 females, 44 knees) who underwent posterior-stabilized TKA using a navigation system were included. Intraoperative knee kinematics involving tibial rotational position relative to the femur and the extent of tibial internal rotation were examined at two time points: 1) after landmarks registration (pre-TKA) and 2) after skin closure (post-TKA). The relationship between the knee flexion angle at one year postoperatively and intraoperative tibial rotational position, or the extent of tibial rotation among several knee flexion angles calculated with a navigation system were investigated. RESULTS: The postoperative knee flexion angle was positively associated with the preoperative flexion angle and intraoperative knee kinematics at post-TKA involving tibial external position relative to the femur at knee extension and the extent of tibial internal rotation from extension to 90° of flexion or to maximum flexion. There was a positive relationship between the extent of tibial internal rotation at pre-TKA and that at post-TKA. CONCLUSIONS: The intraoperative kinematics of the extent of tibial internal rotation at post-TKA was influenced by that at pre-TKA. The greater external position of the tibia relative to the femur at knee extension and the greater extent of tibial internal rotation at post-TKA might lead to good knee flexion angle.

Investigation of Factors Affecting the Clinical Results of Arthroscopic Anterior Talofibular Ligament Repair for Chronic Lateral Ankle Instability.

This study aimed to examine the factors affecting the clinical outcomes of anterior talofibular ligament (ATFL) repair surgery with arthroscopy for chronic lateral ankle instability (CLAI). From 2015 to 2018, 18 consecutive patients diagnosed with CLAI after conservative treatment for ≥3 months underwent arthroscopic ATFL repair surgery using the Broström-Gould technique. Clinical scores at 1 year postoperatively on the Karlsson scoring scale (median, 85 points) and the Japanese Society for Surgery of the Foot scale (median, 90 points) were significantly improved compared with preoperative scores (median, 50 and 66 points; p < .001 and <.001, respectively). The median period to start jogging was 2 and 6 months for patients without (n = 11) and with (n = 7) cartilage damage, respectively, showing a significant difference (p = .006). Four patients with cartilage damage could not return to preinjury sports within 1 year after surgery. In the stress radiographs, the talar tilt angle (TTA) significantly improved from a median of 6° preoperatively to a median of 3.5° postoperatively (p = .002). Talar anterior drawer distance (TAD) significantly improved from a median of 6.5 mm preoperatively to a median of 4.1 mm postoperatively (p < .001). There was no significant difference in TTA or TAD between patients without and with cartilage damage. The period to start jogging postoperatively was significantly correlated with postoperative TTA and TAD. It is suggested that the postoperative period to start activities was delayed because of the larger postoperative TTA and TAD. According to our results, the postoperative period to start activities may depend on cartilage damage and instability remaining postoperatively.

A computer simulation study for preserving the tibial posterior slope in open-wedge high tibial osteotomy.

OBJECTIVE: To measure the medial opening gap and examine a technique for preserving the tibial posterior slope (TPS) in open-wedge high tibial osteotomy (OWHTO) using computer-simulated three-dimensional (3D) surgery. MATERIALS AND METHODS: This study included 24 symptomatic knees from 20 patients (7 men and 13 women; mean age, 67.9 years; range 54-89 years). Digital imaging and communications from computed tomography examination were applied to a 3D picture software program, and several anatomical landmarks were registered. Then, computer simulation of OWHTO as a virtual surgery was performed: the correction angle was decided to make the femorotibial angle 170°, and the TPS did not differ between pre- and postplanification. The distance between the proximal and distal cortices of the medial tibia was measured at three points, which were the anterior (AD), posterior (PD), and longest (LD) distance sites in the sagittal plane, using the 3D view, and the ratios of AD/PD and AD/LD were measured. The anteromedial opening gap was compared to the posteromedial gap and the longest distance gap at the osteotomy site. Spearman's rank correlation coefficient test was used in statistical analysis. RESULTS: Mean AD/PD was 0.740 ± 0.051 (range 0.651-0.850), and mean AD/LD was 0.652 ± 0.040 (range 0.571-0.768). The correction angle was not associated with the values of both AD/PD and AD/LD. CONCLUSIONS: Difference in AD/PD and AD/LD between each patient was regarded as a significant variation. Therefore, preoperative planification with 3D computer simulation to measure AD/PD and AD/LD may be helpful to avoid a significant increase in TPS.

Comparison of Chest Compression Quality Using Wing Boards versus Walking Next to a Moving Stretcher: A Randomized Crossover Simulation Study.

BACKGROUND: When a rescuer walks alongside a stretcher and compresses the patient's chest, the rescuer produces low-quality chest compressions. We hypothesized that a stretcher equipped with wing boards allows for better chest compressions than the conventional method. METHODS: In this prospective, randomized, crossover study, we enrolled 45 medical workers and students. They performed hands-on chest compressions to a mannequin on a moving stretcher, while either walking (the walk method) or riding on wings attached to the stretcher (the wing method). The depths of the chest compressions were recorded. The participants' vital signs were measured before and after the trials. RESULTS: The average compression depth during the wing method (5.40 ± 0.50 cm) was greater than during the walk method (4.85 ± 0.80 cm; p < 0.01). The average compression rates during the two minutes were 215 ± 8 and 217 ± 5 compressions in the walk and wing methods, respectively (p = ns). Changes in blood pressure (14 ± 11 vs. 22 ± 14 mmHg), heart rate (32 ± 13 vs. 58 ± 20 bpm), and modified Borg scale (4 (interquartile range: 2-4) vs. 6 (5-7)) were significantly lower in the wing method cohort compared to the walking cohort (p < 0.01). The rescuer's size and physique were positively correlated with the chest compression depth during the walk method; however, we found no significant correlation in the wing method. CONCLUSIONS: Chest compressions performed on the stretcher while moving using the wing method can produce high-quality chest compressions, especially for rescuers with a smaller size and physique.

Intraoperative bacterial contamination in total hip and knee arthroplasty is associated with operative duration and peeling of the iodine-containing drape from skin.

BACKGROUND: Surgical site infection (SSI) and periprosthetic joint infection are the most important problems after total hip arthroplasty (THA) and total knee arthroplasty (TKA). This study aimed to examine the risk factors for intraoperative bacterial contamination in THA and TKA. METHODS: One hundred and seven hips underwent THA, while 74 knees underwent TKA. After the implant was placed, a swab sample for bacterial culture was collected around the skin incision. At the time of specimen collection, patients were separated into two groups based on whether the iodine-containing drape remained adhered to the skin (group DR) or the iodine-containing drape was peeled off (group ND). Patient characteristics, including age, height, body weight, body mass index, operative duration, intraoperative blood loss, surgical procedures, and condition of the iodine-containing drape, were compared between patients with positive and negative bacterial cultures. RESULTS: In THA, which had a shorter operative duration than TKA (p < 0.001), there was one case of bacterial contamination. In TKA, there were ten cases of positive bacterial contamination, all in group ND. Postoperative SSI occurred in one case. The binomial logistic regression analyses confirmed that TKA [OR 16.562 (95% CI 2.071 to 132.430), p < 0.01] was a high risk factor of bacterial contamination compared to THA and the group ND [OR 0.000 (95% CI 0.000), p < 0.001] had a low risk of bacterial contamination compared to the group DR. In TKAs, operative duration was the risk factor of bacterial contamination [OR 1.026 (95% CI 1.000 to 1.054), p < 0.01]. CONCLUSIONS: Intraoperative bacterial contamination increases in procedures with long operating time and may be suppressed by proper use of an iodine-containing drape.

Pain relief after more than 24 hours of preoperative skin traction in patients with intertrochanteric fractures: A retrospective comparative cohort study.

AIM: The primary aim of the study was to investigate pain relief after more than 24 h of preoperative skin traction (because of delay in surgery due to comorbidities and system issues) in patients with intertrochanteric fractures. METHOD: We performed a retrospective comparative cohort study of 56 patients who underwent intramedullary nailing for the treatment of intertrochanteric fractures and who had waited for surgery for more than 48 h after admission due to comorbidities or system issues. Preoperative therapy was randomly selected with a ratio of one to two and patients classified as skin traction (n = 18) or no traction (n = 38). The Verbal Rating Scale (VRS) was used to assess pain at 12-60 h post-admission. RESULTS: There was no significant difference in VRS at 12 h after admission (1.1 ± 1.0 vs. 0.8 ± 0.9, p = 0.73), but patients who received skin traction had a lower VRS pain score at 24-60 h after admission compared to those with no traction (24 h, 0.4 ± 0.8 vs. 1.1 ± 1.0, p < 0.05; 36 h, 0.2 ± 0.5 vs. 0.9 ± 0.9, p < 0.05; 48 h, 0.2 ± 0.4 vs. 0.8 ± 0.9, p < 0.05; 60 h, 0.2 ± 0.4 vs. 0.9 ± 0.9, p < 0.05). CONCLUSION: Skin traction for patients with intertrochanteric fractures for more than 24 h preoperatively resulted in a lower VRS pain score. Therefore, more than 24 h of preoperative skin traction for patients with intertrochanteric fractures may give effective pain relief in situations where surgery is delayed.