Assessment of arthrogenic quadriceps muscle inhibition by physical examination in the supine position during isometric contraction is feasible as demonstrated by electromyography: a cross-sectional study.

BACKGROUND: Preventing severe arthrogenic muscle inhibition (AMI) after knee injury is critical for better prognosis. The novel Sonnery-Cottet classification of AMI enables the evaluation of AMI severity but requires validation. This study aimed to investigate the electromyography (EMG) patterns of leg muscles in the examination position from the classification during isometric contraction to confirm its validity. We hypothesised that the AMI pattern, which is characterised by quadriceps inhibition and hamstring hypercontraction, would be detectable in the supine position during isometric contraction. METHODS: Patients with meniscal or knee ligament injuries were enrolled between August 2023 and May 2024. Surface EMG was assessed during submaximal voluntary isometric contractions (sMVIC) at 0° extension in the supine position for the vastus medialis (VM) and vastus lateralis (VL) muscles and at 20° flexion in the prone position for the semitendinosus (ST) and biceps femoris (BF) muscles. Reference values for normalisation were obtained from the EMG activity during the gait of the uninjured leg. The Kruskal-Wallis test was used to compare the activation patterns of the muscle groups within the same leg, and the post-hoc tests were conducted using the Mann-Whitney U test and Bonferroni correction. RESULTS: Electromyographic data of 40 patients with knee injuries were analyzed. During sMVIC, the extensor and flexor muscles of the injured leg showed distinct behaviours (P < 0.001), whereas the uninjured side did not (P = 0.144). In the injured leg, the VM differed significantly from the ST (P = 0.018), and the VL differed significantly from the ST and BF (P = 0.001 and P = 0.026, respectively). However, there were no statistically significant differences within the extensor muscle groups (VM and VL, P = 0.487) or flexor muscle groups (ST and BF, P = 0.377). CONCLUSION: AMI was detectable in the examination position suggested by the Sonnery-Cottet classification. The flexor and extensor muscles of the injured leg exhibited distinct activation behaviours, with inhibition predominantly occurring in the quadriceps muscles, whereas the hamstrings showed excitation.

Clinical Feasibility of a Markerless Gait Analysis System.

Background: The gait analysis method that has been used in clinical practice to date is an optical tracking system (OTS) using a marker, but a markerless gait analysis (MGA) system is being developed because of the expensive cost and complicated examination of the OTS. To apply this MGA clinically, a comparative study of the MGA and OTS methods is necessary. The purpose of this study was to evaluate the compatibility between the OTS and the MGA methods and to evaluate the usefulness of the MGA system in actual clinical settings. Methods: From March 2021 to August 2021, 14 patients underwent gait analysis using the OTS and MGA system, and the spatiotemporal parameters and kinematic results obtained by the 2 methods were compared. To evaluate the practicality of the MGA system in an actual clinical setting, MGA was performed on 14 symptomatic children with idiopathic toe walking, who had been treated with a corrective cast, and the pre-cast and post-cast results were compared. For the OTS, the Motion Analysis Eagle system was used, and for MGA, DH Walk was used. Results: The spatiotemporal parameters showed no significant difference between the OTS and MGA system. The joint angle graphs of the kinematics along the sagittal plane showed similar shapes as a whole, with particularly high correlations in the hip and knee (pelvis: 29.4%, hip joint: 96.7%, knee joint: 94.9%, and ankle joint: 68.5%). A quantified comparison using the CORrelation and Analysis (CORA) score also showed high similarity between the 2 methods. The MGA results of pre-cast application and post-cast removal for children with idiopathic toe walking showed a statistically significant improvement in ankle dorsiflexion after treatment (p < 0.001). Conclusions: MGA showed a good correlation with the conventional OTS in terms of spatiotemporal parameters and kinematics. We demonstrated that ankle sagittal kinematics improved after treatment by corrective cast in children with idiopathic toe walking using the MGA method. Thus, after the improvement of a few limitations, the MGA system may soon be able to be clinically applied.

Nested Case Control Study on the Risk of Suicide Death in Elderly Patients with Pelvic Fractures Using a Nationwide Cohort.

Background: The aim of this study was to investigate the incidence rate of suicide deaths in elderly patients with pelvic fractures using a nationwide database and to analyze change in the risk of suicide death overtime after pelvic fractures compared to controls. Methods: We used the National Health Insurance Service-Senior cohort (NHIS-Senior) of South Korea. Cases and controls were matched for sex, age, history of hospital admission within 1 year, and presence of depression on the date of suicide death. Controls were collected by random selection at a 1 : 5 ratio from patients at risk of becoming cases when suicide cases were collected. Incident pelvic fractures were identified from the NHIS-Senior as follows: first admission during the observational period (2002-2015) to an acute care hospital with a diagnostic code of International Statistical Classification of Diseases and Related Health Problems, 10th revision S321, S322, S323, S324, S325, or S328 and age 65-99 years. Conditional logistic regression analysis was performed to evaluate the association between pelvic fractures and the risk of suicide death. Results: A total of 2,863 suicide cases and 14,315 controls were identified. Suicide case patients had been more frequently exposed to steroids (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.21-1.45), benzodiazepines (OR, 1.76; 95% CI, 1.61-1.93), and non-steroidal anti-inflammatory drugs (OR, 1.18; 95% CI, 1.07-1.29). Pelvic fractures within 1 year from the date of suicide death were statistically significantly associated with increased risk of suicide (adjusted OR [AOR], 2.65; 95% CI, 1.29-5.45; p = 0.008) compared to controls. The risk of suicide death declined as the incidence date of pelvic fracture was more remote from the date of suicide death: AORs of 2.59 (95% CI, 1.33-5.04; p = 0.005) within 2 years and 2.13 (95% CI, 1.15-3.95; p = 0.017) within 3 years. However, there was no statistical significance in the increased risk of suicide death for pelvic fractures that had occurred ≥ 4 years ago (p > 0.05). Conclusions: Pelvic fractures in the elderly population increased the risk of suicide death within 3 years, suggesting the need for psychiatric support among elderly patients with pelvic fractures.

Comparative Interrupted Time Series Analysis of Long-term Direct Medical Costs in Patients With Hip Fractures and a Matched Cohort: A Large-database Study.

BACKGROUND: Previous studies on medical costs in patients with hip fractures have focused on medical costs incurred for a short period after the injury. However, patients often had comorbidities before their hip fractures that would have affected medical costs even had they not sustained a fracture. Consequently, these studies may have overestimated the costs associated with hip fractures and did not characterize the duration of increased medical costs adequately. Without knowing this crucial information, it is difficult to craft thoughtful health policy to support these patients' needs. QUESTIONS/PURPOSES: (1) To compare the direct medical costs for 5 years before fracture and up to 5 years after injury in a group of patients who underwent hip fracture surgery with a matched group of patients who did not experience a hip fracture, (2) to analyze the duration over which the increased direct medical costs associated with a hip fracture continues, and (3) to analyze whether there is a difference in direct medical costs according to age group using a nationwide claims database in South Korea. METHODS: The National Health Insurance Service Sample cohort in South Korea consisted of 1 million patients who were selected using a systematic, stratified, random sampling method from 48,222,537 individuals on December 31, 2006. Under a compulsory social insurance system established by the National Health Insurance Act, all patients were followed until 2015. Patients with hip fractures and matched controls were selected from the National Health Insurance Service sample of South Korea. Patients with hip fractures were defined as those who were hospitalized with a diagnosis of femoral neck fracture or intertrochanteric fracture and who underwent surgical treatment. We excluded patients with hip fractures before January 1, 2007 to ensure a minimum 5-year period that was free of hip fractures. Patients with hip fractures were matched with patients of the same age and gender at the date of admission to an acute care hospital for surgery (time zero). If patients with hip fractures died during the follow-up period, we performed matching among patients whose difference from the time of death was within 1 month. This method of risk-set matching was repeated sequentially for the next patient until the last patient with a hip fracture was matched. We then sequentially performed 1:5 random sampling for each risk set. A total of 3583 patients in the hip fracture cohort (patients with hip fractures) and 17,915 patients in the matched cohort (those without hip fractures) were included in this study. The mean age was 76 ± 9 years, and 70% were women in both groups. Based on the Charlson comorbidity index score, medication, and medical history, the patients with hip fractures had more comorbidities. Person-level direct medical costs per quarter were calculated for 5 years before time zero and up to 5 years after time zero. Direct medical costs were defined as the sum of that insurer's payments (that is, the National Health Insurance Service's payments), and that patient's copayments, excluding uncovered payments. We compared direct medical costs between patients with hip fractures and the patients in the matched cohort using a comparative interrupted time series analysis. The difference-in-difference estimate is the ratio of the differences in direct medical costs before and after time zero in the hip fracture cohort to the difference in direct medical costs before and after time zero in the matched cohort; the difference in difference estimates were calculated each year after injury. To identify changes in direct medical cost trends in patients with hip fractures and all subgroups, joinpoint regression was estimated using statistical software. RESULTS: The direct medical costs for the patients with hip fractures were higher than those for patients in the matched cohort at every year during the observation period. The difference in direct medical costs between the groups before time zero has increased every year. The direct medical costs in patients with hip fractures was the highest in the first quarter after time zero. Considering the differential changes in direct medical costs before and after time zero, hip fractures incurred additional direct medical costs of USD 2514 (95% CI 2423 to 2606; p < 0.01) per patient and USD 264 (95% CI 166 to 361; p < 0.01) per patient in the first and second years, respectively. The increase in direct medical costs attributable to hip fracture was observed for 1.5 to 2 years (difference-in-difference estimate at 1 year 3.0 [95% CI 2.8 to 3.2]; p < 0.01) (difference-in-difference estimate at 2 years 1.2 [95% CI 1.1 to 1.3]; p < 0.01; joinpoint 1.5 year). In the subgroups of patients younger than 65, patients between 65 and 85, and patients older than 85 years of age, the increase in direct medical costs attributable to hip fracture continued up to 1 year (difference-in-difference estimate ratio at 1 year 2.7 [95% CI 2.1 to 3.4]; p < 0.01; joinpoint 1 year), 1.5 to 2 years (difference-in-difference estimate ratio at 1 year 2.8 [95% CI 2.6 to 3.1]; p < 0.01; difference-in-difference estimate ratio at 2 years 1.2 [95% CI 1.1 to 1.3]; p < 0.01; joinpoint 1.5 years), and 39 months to 5 years (difference-in-difference estimate ratio at 1 year 5.2 [95% CI 4.4 to 6.2]; p < 0.01; difference-in-difference estimate ratio at 5 years 2.1 [95% CI 1.4 to 3.1]; p < 0.01; joinpoint 39 months) from time zero, respectively. CONCLUSION: The direct medical costs in patients with hip fractures were higher than those in the matched cohort every year during the 5 years before and after hip fracture. The increase in direct medical costs because of hip fractures was maintained for 1.5 to 2 years and was greater in older patients. Based on this, we suggest that health policies should focus on patients' financial and social needs, with particular emphasis on the first 2 years after hip fracture with stratification based on patients' ages. LEVEL OF EVIDENCE: Level II, economic analysis.

Clinical and Radiological Outcomes after Various Treatments of Midshaft Clavicle Fractures in Adolescents.

BACKGROUD: Controversy exists about the optimal treatment of midshaft clavicle fractures in the presence of significant displacement, comminution, or shortening of the fracture in adolescents. The purpose of this study was to compare the clinical and radiological outcomes of 4 different treatments for midshaft clavicle fractures in adolescents: conservative treatment with a figure-of-8 (FO8) brace, open reduction and internal fixation with a plate (OPL), minimally invasive plate osteosynthesis (MIPO), and intramedullary nail fixation with a threaded Steinmann pin (TSP). METHODS: A total of 94 teenagers with midshaft clavicle fractures were divided into the FO8, OPL, MIPO, and TSP groups (n = 24, 33, 16, and 21, respectively). We analyzed clinical and radiological outcomes and complications in each group and compared the results among the groups. RESULTS: All groups showed satisfactory clinical and radiological outcomes, but each group showed different results for the assessment items. The Constant-Murley scores were higher in the operated groups than in the FO8 group. Recovery of joint motion was faster in the operated groups. The TSP group had the highest cosmetic satisfaction with respect to the satisfaction score and measured scar length. Fracture union was achieved in all patients. At the final follow-up, the bone length was closer to normal in the OPL and TSP groups than in the FO8 and MIPO groups, and angulation was less in the OPL and TSP groups than in the MIPO and FO8 groups. The TSP and MIPO groups obtained faster bone healing than the OPL and FO8 groups. In the operated groups, 9 patients had metal-induced irritating symptoms; 1, supraclavicular nerve injury symptoms; and 4, refractures after plate removal. CONCLUSIONS: The nonoperatively treated group had no iatrogenic complications. The operated groups complained of various disadvantages induced by surgery; however, these groups achieved faster functional recovery and slightly better radiological and functional results than the nonoperative group.

Changes in Gait and Radiographic and Clinical Results of Calcaneal Lengthening Osteotomy in Children with Idiopathic Flexible Flatfoot.

BACKGROUD: In this study, we aimed to analyze kinematic and kinetic changes in gait and to assess radiographic and clinical improvement after calcaneal lengthening osteotomy (CLO) in children with idiopathic symptomatic flexible flatfoot deformities. METHODS: The study group consisted of 22 children (28 feet) with idiopathic symptomatic flexible flatfoot, which was treated by CLO as an index operation. We excluded patients with flatfoot that developed secondary to neuromuscular diseases. There were 18 boys (22 feet) and 4 girls (6 feet). The average age of the patients was 10.8 ± 1.51 years. Surgical results were assessed by radiologic imaging, clinical evaluation, and gait analysis, which were performed before surgery and 1 year after surgery. Medical records were reviewed to check postoperative complications. RESULTS: Talonavicular coverage was recovered to 16.7° from 32.7° (p < 0.01). Lateral talo-first metatarsal angle and calcaneal pitch angle increased by 20.1° and 9.9°, respectively (p < 0.01). Weight-bearing radiographs demonstrated a decrease in the anteroposterior angle and lateral talocalcaneal angle by 6.9° and 10°, respectively (p < 0.01). Hindfoot valgus was corrected to near neutral position after CLO. Kinematic results showed that the ankle valgus angle in the coronal plane was reduced from 35.48° preoperatively to 16.64° postoperatively during gait (p < 0.05). The preoperative out-toeing gait (preoperative foot progression angle, 20.31°) was also normalized to 14.21° postoperatively. The kinetics results showed that the push-off moment (maximum ankle plantar flexion) on the sagittal plane increased from 0.66 Nm/kg preoperatively to 0.83 Nm/kg postoperatively (p < 0.01). The mean Yoo score was 9.2 ± 1.05 postoperatively: satisfactory in 24 cases (86%) and unsatisfactory in 4 cases. Of the 4 unsatisfactory cases, 2 cases were overcorrection and 2 cases were undercorrection, and 3 of them were well managed by wedge foot insoles. CONCLUSIONS: The 3-dimensional deformities of the flexible flatfoot were effectively corrected by CLO, based on the morphological assessment using radiologic imaging. The correction was well maintained during gait at 1 year after the operation.

The effect of surgery type on mortality in elderly patients with pertrochanteric femoral fracture: A Korean nationwide cohort study.

BACKGROUND/OBJECTIVE: The purpose of this study is to analyze the effect of surgical methods on mortality and the relative risk of patients who underwent internal fixation (IF) or hemiarthroplasty (HA) after being diagnosed as a pertrochanteric fracture over 65 years old in a Korean nationwide cohort with a single insurance medical system. METHODS: The Korean National Health Insurance Service-Senior cohort (NHIS-Senior, NHIS-2018-2-111) was used in this study. The eligibility criteria for incident hip fracture patients were the following: (1) first-time admission to acute care hospitals (index admission) with pertrochanteric fracture (ICD-10 S721), (2) three years of hip fracture-free period, (3) recipients of typical surgeries including IF, HA, (4) age between 65 and 99. RESULTS: a total of 7223 patients were enrolled in the cohort. There were 1662 patients (23%) in the HA group and 5561 patients (77%) in the IF group. Mortality rates of the IF group and HA group were 13.46 and 17.94 cases per 100 person-years, respectively. In the multivariable-adjusted Cox proportional hazard model, the HA group had 1.22 times more hazard of all-cause mortality than IF group (aHR 1.22, 95% CI 1.13-1.32). In subgroup analysis, aged 65-79 and female patients showed a prominent association between surgery type and mortality (aHR 1.52, 95% CI 1.29-1.79). CONCLUSIONS: In patients with pertrochanter fracture over 65 years, 1.22-fold mortality rate was observed when HA was performed compared to that of IF, and the difference in mortality was particularly prominent within 1-year after surgery.

Biomechanical Evaluation of Internal Fixation of Pauwels Type III Femoral Neck Fractures: A Systematic Review of Various Fixation Methods.

BACKGROUND: The purpose of this systematic review was to investigate various fixation methods or implants used in the treatment of Pauwels type III femoral neck fractures. METHODS: PubMed Central, OVID Medline, Cochrane Collaboration Library, Web of Science, Embase, and AHRQ databases were searched to identify relevant studies published until August 2017 with English language restriction. Studies were selected on the basis of the following inclusion criteria: biomechanical study of Pauwels type III femoral neck fractures and the use of dynamic hip screw (DHS) or multiple screw fixation or other devices for fixation of the fracture. RESULTS: A total of 15 studies were included in the systematic review. Eight studies were conducted using cadavers, six studies using sawbones, and one using a finite element model. During the mechanical testing, each study measured mechanical stiffness, failure to cyclic loading, failure to vertical loading of each fixation device. DHS was included in 11 studies, multiple screw fixation in 10 studies, and other devices in six studies. Baitner et al. and Samsami et al. reported that the mechanical stiffness of DHS was superior to three inverted triangular screw fixation. Hawks et al. and Gumustas et al. reported that using a transverse calcar screw can withstand vertical loading better than three inverted triangular screw fixation. In addition, there were some studies where instruments such as Intertan nail, locking plate or other devices showed excellent biomechanical properties. CONCLUSIONS: There are a variety of methods and instruments for fixation of the Pauwels type III fractures. However, it is difficult to conclude that any method is more desirable because there are advantages and disadvantages to each method. Therefore, we should pay attention to the implant choice and consider adequate weight bearing affecting the stiffness of the implant.

Acute Cholecystitis in Elderly Patients after Hip Fracture: a Nationwide Cohort Study.

BACKGROUND: Because acute cholecystitis in elderly hip fracture is not easily distinguishable from other gastrointestinal symptoms and involves atypical clinical behaviors, it may not be diagnosed in the early stage. However, the exact incidences could not be reported. We utilized data from a nationwide claims database and attempted to assess the incidence of acute cholecystitis in elderly hip fracture patients and how cholecystitis affects mortality rates after hip fracture. METHODS: Study subjects were from the Korean National Health Insurance Service-Senior cohort. From a population of approximately 5.5 million Korean enrollees > 60 years of age in 2002, a total of 588,147 participants were randomly selected using 10% simple random sampling. The subjects included in this study were those who were over 65 years old and underwent surgery for hip fractures. RESULTS: A total of 15,210 patients were enrolled in the cohort as hip fracture patients. There were 7,888 cases (51.9%) of femoral neck fracture and 7,443 (48.9%) cases of hemiarthroplasty. Thirty-six patients developed acute cholecystitis within 30 days after the index date (30-day cumulative incidence, 0.24%). Four of the 36 acute cholecystitis patients (11.1%) died within 30 days versus 2.92% of patients without acute cholecystitis. In the multivariate-adjusted Poisson regression model, hip fracture patients with incident acute cholecystitis were 4.35 (adjusted risk ratio 4.35; 95% confidence interval, 1.66-11.37; P = 0.003) times more likely to die within 30 days than those without acute cholecystitis. CONCLUSION: Incidence of acute cholecystitis in elderly patients after hip fracture within 30 days after the index date was 0.24%. Acute cholecystitis in elderly hip fracture patients dramatically increases the 30-day mortality rate by 4.35-fold. Therefore, early disease detection and management are crucial for patients.

Gait analysis after total hip arthroplasty using direct anterior approach versus anterolateral approach: a systematic review and meta-analysis.

BACKGROUND: Comparative studies of total hip arthroplasty using the direct anterior approach (DAA) compared with the anterolateral approach (ALA) by gait analysis compared the results of the two groups, the damage to the abductor muscle, with objective and detailed kinematic as well as kinetic data of actual gait. The purpose of this systematic review was to analyze the differences in gait such as time-dependent parameters, kinetics, and kinematics after THA using the DAA compared with ALA. METHODS: PubMed Central, OVID Medline, Cochrane Collaboration Library, Web of Science, EMBASE and AHRQ carried out a comprehensive search for all relevant randomized controlled trials and comparative studies, up to December 2018. Based on the following criteria, studies were selected: 1) study design: randomized controlled trials or non-randomized comparative studies; 2) study population: patients with primary osteoarthritis or avascular necrosis; 3) intervention: total hip arthroplasty by DAA or ALA; 4) Kinetic and kinematic data after gait analysis in the plains during postoperative follow-up. RESULTS: Of the 148 studies, 7 randomized controlled trials and 5 comparative studies were finally included in this systematic review. The peak hip flexion within 3 months after surgery was described in two studies and was significantly higher in the DAA group. (OR = 1.90; 95% CI [1.67,2.13]; P < 0.01, Z = 16.18). The gait speed within 3 months after surgery was reported in 3 studies and was significantly higher in the DAA group than in the ALA group. (SMD = 0.17; 95% CI [0.12,0.22]; P < 0.01, Z = 6.62) There was no difference between the two groups in stride length, step length, and hip range of motion in sagittal plane. CONCLUSIONS: In this meta-analysis, gait speed and peak hip flexion within 3 months after surgery were significantly higher in the DAA group than in the ALA group. Despite a few significant differences between two approaches, determining whether the reported differences in terms of postoperative gait values are clinically meaningful remains a substantial challenge.

Changes in gait parameters after femoral derotational osteotomy in cerebral palsy patients with medial femoral torsion.

Medial femoral torsion (MFT) is a common pathologic gait in cerebral palsy (CP) children that can be corrected by femoral derotational osteotomy (FDO). It is not clearly known as to how much various gait parameters change after FDO. The aim of this study was to quantify changes in gait parameters after FDO. The study group included 19 young CP patients (28 limbs, age<20 years, average age: 13.2 years) with symptomatic MFT, treated with distal FDO. The study group was divided into two groups: the unilateral FDO group (UG) and the bilateral FDO group (BG). The mean degree of derotation was 24.6° (25.0° for UG, 24.4° for BG). Pre-FDO and post-FDO values of Staheli's rotational profiles and kinematic data were compared. A paired t-test and Pearson's correlation were used for statistical analysis. The mean internal hip rotation was 71.4±6.9° before surgery and 48.6±10.7° after surgery in the UG (P<0.05) and it was 63.8±15.8° before surgery and 40.9±9.2° after FDO in the BG (P<0.05). The change in the foot progression angle (FPA) was 12.9° in the UG group (P<0.05) and 12.6° in the BG group (P<0.05). The degree of FPA had changed by about a half of the surgical derotation angle. Changes in the mean hip rotation during gait were 14.8° in the UG (P<0.05) and 6.7° in the BG (P<0.05) groups. The overall pelvic rotation was not changed after surgery. However, in patients with preoperative compensatory pelvic rotation of more than 5°, there was a change of 5.3±4.8° in the UG and 6.6±1.54° in the BG after surgery (P<0.05). There was also a trend showing that the younger the patient, the more the pelvic rotation changed (P=0.069). In-toeing gait because of MFT improved with FDO in CP patients. The expected degree of postoperative correction of FPA and hip rotation is about a half of the FDO degree. The degree of compensatory pelvic rotation should be considered to determine the correction angle of FDO, especially in young patients with preoperative pelvic rotation of more than 5°.

Gait Analysis of Symptomatic Flatfoot in Children: An Observational Study.

BACKGROUND: Flatfoot deformity is a lever arm disease that incurs kinetic inefficiency during gait. The purpose of this study was to measure the degree of kinetic inefficiency by comparing the gait analysis data of a flatfoot group with a normal control group. METHODS: The patient group consisted of 26 children (21 males and 5 females) with symptomatic flatfoot. They were examined with gait analysis between May 2005 and February 2014. Exclusion criteria were patients with secondary flatfoot caused by neuromuscular disorders, tarsal coalition, vertical talus, or others. Patients' mean age was 9.5 years (range, 7 to 13 years). The gait analysis data of the study group and the normal control group were compared. RESULTS: The mean vertical ground reaction force (GRF) in the push-off phase was 0.99 for the patient group and 1.15 for the control group (p < 0.05). The mean ankle moment in the sagittal plane during the push-off phase was 0.89 for the patient group and 1.27 for the control group (p < 0.05). The mean ankle power in the sagittal plane during the push-off phase was 1.38 for the patient group and 2.52 for the control group (p < 0.05). The aforementioned results show that patients with pes planovalgus had a reduction of moment, power, and GRF in the push-off phase during gait. CONCLUSIONS: Symptomatic flatfeet had a moment inefficiency of 30% and power inefficiency of 45% during gait compared to feet with preserved medial longitudinal arches.

Mobile bearing medial unicompartmental knee arthroplasty in patients whose lifestyles involve high degrees of knee flexion: A 10-14year follow-up study.

BACKGROUND: Because Asian populations have different lifestyles, such as squatting and sitting on the floor, from those of Western populations, it is possible that the clinical results and survival rate of unicompartmental knee arthroplasty (UKA) for Asian patients may be different. This study described outcomes of mobile bearing medial UKA for Korean patients. METHODS: A total of the 164 knees treated with mobile bearing UKAs in 147 patients (14 males and 133 females) were reviewed. The mean follow-up period was 12.1years (range 10.1-14). RESULTS: The clinical outcomes, such as the Hospital for Special Surgery Knee score, the Oxford Knee Score and the Knee Society rating system, showed statistically significant improvement from pre-operative to final follow-up (P<0.05). A total of 26 UKAs (15.8%) required revision; the most common reason was bearing dislocation. The 95% confidence interval of survival rate at 12years was 84.1%, with revision for any reason as the end point. CONCLUSIONS: Minimally invasive mobile bearing UKA in Asian patients who required high degrees of knee flexion showed rapid recovery and good clinical outcome. However, they also showed relatively high rates of bearing dislocation and aseptic loosening. Therefore, mobile bearing UKA should only be performed in patients whose lifestyle involves high flexions after carefully considering these risks and benefits.

Three-Dimensional Scapular Kinematics in Patients with Reverse Total Shoulder Arthroplasty during Arm Motion.

BACKGROUND: There have been few reports on altered kinematics of the shoulder after reverse total shoulder arthroplasty (RTSA). We investigated differences in 3-dimensional (3D) scapular motions assessed using an optical tracking system between RTSA treated shoulders and asymptomatic contralateral shoulders during arm motion. METHODS: Thirteen patients who underwent RTSA were assessed for active arm elevation in 2 distinct elevation planes (sagittal plane flexion and scapular plane abduction). Their mean age was 72 years (range, 69 to 79 years) and the mean follow-up was 24.4 months (range, 13 to 48 months). The dominant side was the right side in all the 13 patients, and it was also the side treated with RTSA. Scapular kinematics was recorded with an optical tracking system. The scapular kinematics and the scapulohumeral rhythm (SHR) of the RTSA shoulders and asymptomatic contralateral shoulders were recorded and analyzed during arm elevation. RESULTS: There were no significant differences in internal/external rotation and anterior/posterior tilting of the scapula between shoulders during arm motion (p > 0.05). However, upward rotation of the scapula differed significantly during arm motion (p = 0.035 for sagittal plane flexion; p = 0.046 for scapular plane abduction). There were significant differences in the SHR between the two shoulders (p = 0.016 for sagittal plane flexion; p = 0.021 for scapular plane abduction). CONCLUSIONS: The shoulder kinematics after RTSA showed significant differences from the contralateral asymptomatic shoulders. Increased upward rotation and decreased SHR after RTSA indicate that RTSA shoulders use more scapulothoracic motion and less glenohumeral motion to elevate the arm.

Comprehensive genetic exploration of skeletal dysplasia using targeted exome sequencing.

PURPOSE: The purpose of this study was to evaluate the clinical utility of targeted exome sequencing (TES) as a molecular diagnostic tool for patients with skeletal dysplasia. METHODS: A total of 185 patients either diagnosed with or suspected to have skeletal dysplasia were recruited over a period of 3 years. TES was performed for 255 genes associated with the pathogenesis of skeletal dysplasia, and candidate variants were selected using a bioinformatics analysis. All candidate variants were confirmed by Sanger sequencing, correlation with the phenotype, and a cosegregation study in the family. RESULTS: TES detected "confirmed" or "highly likely" pathogenic sequence variants in 74% (71 of 96) of cases in the assured clinical diagnosis category and 20.3% (13 of 64 cases) of cases in the uncertain clinical diagnosis category. TES successfully detected pathogenic variants in all 25 cases of previously known genotypes. The data also suggested a copy-number variation that led to a molecular diagnosis. CONCLUSION: This study demonstrates the feasibility of TES for the molecular diagnosis of skeletal dysplasia. However, further confirmation is needed for a final molecular diagnosis, including Sanger sequencing of candidate variants with suspected, poorly captured exons.Genet Med 18 6, 563-569.

Screw-Home Movement of the Tibiofemoral Joint during Normal Gait: Three-Dimensional Analysis.

BACKGROUND: The purpose of this study was to evaluate the screw-home movement at the tibiofemoral joint during normal gait by utilizing the 3-dimensional motion capture technique. METHODS: Fifteen young males and fifteen young females (total 60 knee joints) who had no history of musculoskeletal disease or a particular gait problem were included in this study. Two more markers were attached to the subject in addition to the Helen-Hayes marker set. Thus, two virtual planes, femoral coronal plane (P f ) and tibial coronal plane (P t ), were created by Skeletal Builder software. This study measured the 3-dimensional knee joint movement in the sagittal, coronal, and transverse planes of these two virtual planes (P f and P t ) during normal gait. RESULTS: With respect to kinematics and kinetics, both males and females showed normal adult gait patterns, and the mean difference in the temporal gait parameters was not statistically significant (p > 0.05). In the transverse plane, the screw-home movement occurred as expected during the pre-swing phase and the late-swing phase at an angle of about 17°. However, the tibia rotated externally with respect to the femur, rather than internally, while the knee joint started to flex during the loading response (paradoxical screw-home movement), and the angle was 6°. CONCLUSIONS: Paradoxical screw-home movement may be an important mechanism that provides stability to the knee joint during the remaining stance phase. Obtaining the kinematic values of the knee joint during gait can be useful in diagnosing and treating the pathological knee joints.

Modified Stoppa approach for surgical treatment of acetabular fracture.

BACKGROUND: We analyzed the extent of the comminution in the acetabular weight-bearing area, the clinical and radiographic results, and the complications after a minimum 2-year follow-up of the modified Stoppa approach for the treatment of acetabular fractures, and we attempted to evaluate the efficacy of the operative technique. METHODS: All of the 22 patients, who needed the anterior approach for the treatment of acetabular fractures at our hospital from November 2007 to November 2010, were subjected to surgery via the modified Stoppa approach. Fracture pattern, operative time, blood loss during the operation, quality of reduction, number of bony fragments in the acetabular weight-bearing area, and postoperative complications were assessed by retrospectively analyzing the medical records and the radiographic examinations. The results after the operation were analyzed based on the criteria of Matta. RESULTS: The clinical results were excellent in 3 cases, good in 13 cases, and poor in 4 cases, while the radiographic results were excellent in 5 cases, good in 13 cases, and poor in 2 cases. Although the quality of reduction and the clinical results according to the extent of comminution were statistically significant (p = 0.03 and p = 0.04, respectively), the radiographic results were not statistically significant (p = 0.74). CONCLUSIONS: It can be concluded that the modified Stoppa approach could be used as an alternative to the classic ilioinguinal approach. In addition, comminution of the acetabular fracture was an important factor causing non-anatomic reduction and finally unsatisfactory clinical results.

Anatomic Single Bundle Anterior Cruciate Ligament Reconstruction by Low Accessory Anteromedial Portal Technique: An In Vivo 3D CT Study.

PURPOSE: Proper femoral tunnel position is important for anatomical reconstruction of the anterior cruciate ligament (ACL). The purpose of this study was to evaluate the positions of femoral and tibial tunnels created using an accessory anteromedial portal technique in single bundle ACL reconstruction. MATERIALS AND METHODS: The femoral tunnel was targeted at the mid-portion of the ACL bundles. We evaluated postoperative computed tomography scans of 32 patients treated by ACL reconstruction using a free-hand low accessory anteromedial portal technique. On the tibial side, the tunnel position was evaluated using Tsukada's method. On the femoral side, the position was evaluated using 1) the quadrant method, 2) Mochizuki's method, 3) Mochizuki's method, and 4) Takahashi's method. Tunnel obliquity was also evaluated. RESULTS: The mean tibial tunnel position was located at 44.6%±2.5% anterior from the anterior margin and 48.0%±3.0% in medial from the medial margin. The mean femoral tunnel position was located at the center between the anteromedial and posterolateral bundles: Quadrant method, 26.7%±2.7%/30.0%±2.9%; Watanabe's method, 37.7%±2.5%/26.6%±2.2%; Mochizuki's method, 38.7%±2.7%; Takahashi's method, 21.8%±2.2%. The mean femoral tunnel obliquity was 57.7°±6.2° in the sagittal plane and 49.9°±5.6° in the coronal plane. CONCLUSIONS: In anatomic single bundle ACL reconstruction, the low anteromedial portal technique can restore accurate position of the native footprint. Accurate femoral tunnel position facilitates recovery of stability and decreases graft failure rate.

Arthroscopic versus posterior endoscopic excision of a symptomatic os trigonum: a retrospective cohort study.

BACKGROUND: Both subtalar arthroscopic and posterior endoscopic techniques are used to treat posterior ankle impingement syndrome (PAIS). However, there have been no studies comparing the 2 procedures. HYPOTHESIS: Both arthroscopic and endoscopic excisions of the os trigonum are safe and effective in treating PAIS. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Twenty-eight patients were treated with excision of the os trigonum either by an arthroscopic (16 patients) or endoscopic (12 patients) technique. The mean patient age was 29.8 years (range, 17-55 years), and the mean follow-up period was 30 months (range, 18-58 months). Preoperative and postoperative visual analog scale (VAS) score for pain, American Orthopaedic Foot and Ankle Society (AOFAS) score, and Maryland Foot Score (MFS) were used to analyze the functional results. Duration of surgery, time to return to sports (RTS), and patient satisfaction were evaluated as well. The size of the os trigonum was measured using T1-weighted sagittal magnetic resonance imaging (MRI). The clinical and MRI results were compared between the 2 groups. RESULTS: The VAS score, AOFAS score, and MFS for both the arthroscopic group (preoperative: 6.3, 63.8, and 61.5, respectively; postoperative: 1.2, 89.9, and 89.6, respectively) and endoscopic group (preoperative: 6.7, 64.8, and 62.5, respectively; postoperative: 1.2, 89.9, and 88.4, respectively) improved significantly (P < .01). The mean surgery and RTS times were 39.4 minutes and 7.5 weeks in the arthroscopic group and 34.8 minutes and 8.0 weeks in the endoscopic group, respectively (P > .05). All patients were satisfied with the results. There were no significant differences between the 2 groups in the preoperative and postoperative VAS score, AOFAS score, or MFS (P > .05). The mean size of the os trigonum was 11.1 × 8.8 mm(2) in the arthroscopic group and 12.6 × 10.4 mm(2) in the endoscopic group, and the difference was significant (P < .05). Two patients underwent both arthroscopic and endoscopic procedures because of technical difficulty in removing the large os trigonum arthroscopically. CONCLUSION: Both arthroscopic and posterior endoscopic excisions of the os trigonum were safe and effective in treating PAIS. The arthroscopic procedure was more demanding, especially in cases of a large os trigonum. The posterior endoscopic approach had the advantage of addressing problems in the posterior ankle joint and allowed a more extensive release of the flexor hallucis longus.

Reconstruction of the lateral ankle ligament with a long extensor tendon graft of the fourth toe.

BACKGROUND: The treatment of lateral ankle instability is challenging when the remaining ligamentous tissue is insufficient. Anatomic reconstruction with a tendon graft is a good option that can produce a stable ankle and avoid the complications of a nonanatomic tenodesis procedure. HYPOTHESIS: A new technique for anatomically reconstructing the lateral ligaments of the ankle using an extensor digitorum longus tendon graft of the fourth toe will be effective for treating lateral ankle instability with chronic ligamentous insufficiency. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty-four patients were treated with anatomic reconstruction of the ligaments using the long extensor tendon of the fourth toe. The mean age was 35.7 years (range, 16-53 years). The minimum follow-up was 24 months (range, 24-57 months; mean, 37 months). There were 17 cases of chronic ligamentous insufficiency, 3 failed Brostrom operations, and 4 others. Preoperative and postoperative Karlsson scales were used to analyze the functional results. The anterior displacement and the talar tilt angle on standard stress radiography of the talocrural joint were measured preoperatively and at the time of last follow-up for comparison. RESULTS: The results on the Karlsson scale increased from 48.0 ± 4.2 points preoperatively to 92.2 ± 3.8 points at the latest follow-up (P < .01). Radiographically, the mean anterior displacement was 6.7 ± 1.2 mm before operation and 3.4 ± 0.6 mm at the latest follow-up (P < .01). The mean talar tilt angle was 12.3° ± 1.1° before the operation and 4.3° ± 0.8° at the latest follow-up (P < .01). CONCLUSION: Anatomic reconstruction of the lateral ankle ligaments using the long extensor tendon of the fourth toe appears to be an effective surgical option for chronic insufficiency of the lateral ankle ligament.