• Hip & pelvis
• /
• v.35 no.2
• /
• pp.88-98
• /
• 2023

Purpose: The objectives of this study were to examine the prevalence and risk factors for development of periprosthetic occult femoral fractures during primary cementless total hip arthroplasty (THA) and to assess the clinical consequences of these fractures. Materials and Methods: A total of 199 hips were examined. Periprosthetic occult femoral fractures were defined as fractures not detected intraoperatively and on postoperative radiographs, but only observed on postoperative computed tomography (CT). Clinical, surgical, and radiographic analysis of variables was performed for identification of risk factors for periprosthetic occult femoral fractures. A comparison of stem subsidence, stem alignment, and thigh pain between the occult fracture group and the non-fracture group was also performed. Results: Periprosthetic occult femoral fractures were detected during the operation in 21 (10.6%) of 199 hips. Of eight hips with periprosthetic occult femoral fractures that were detected around the lesser trochanter, concurrent periprosthetic occult femoral fractures located at different levels were detected in six hips (75.0%). Only the female sex showed significant association with an increased risk of periprosthetic occult femoral fractures (odds ratio for males, 0.38; 95% confidence interval, 0.15-1.01; P=0.04). A significant difference in the incidence of thigh pain was observed between the occult fracture group and the non-fracture group (P<0.05). Conclusion: Occurrence of periprosthetic occult femoral fractures is relatively common during primary THA using tapered wedge stems. We recommend CT referral for female patients who report unexplained early postoperative thigh pain or developed periprosthetic intraoperative femoral fractures around the lesser trochanter during primary THA using tapered wedge stems.

• Hip & pelvis
• /
• v.34 no.1
• /
• pp.56-61
• /
• 2022

Purpose: Histopathologic analysis of femoral head specimens following total hip arthroplasty (THA) is a routine practice that represents a significant use of health care resources. However, it occasionally results in discovery of undiagnosed hematopoietic malignancy and other discrepant diagnoses such as avascular necrosis. The purpose of this study was to determine the rate of discordant and discrepant diagnoses discovered from routine histopathological evaluation of femoral heads following THA and perform a cost analysis of this practice. Materials and Methods: A review of patients undergoing primary THA between 2004-2017 was conducted. A comparison of the surgeon's preoperative and postoperative diagnosis, and the histopathologic diagnosis was performed. In cases where the clinical and histopathology differed, a review determined whether this resulted in a change in clinical management. Medicare reimbursement and previously published cost data corrected for inflation were utilized for cost calculations. Results: A review of 2,134 procedures was performed. The pathologic diagnosis matched the postoperative diagnosis in 96.0% of cases. Eighty-three cases (4.0%) had a discrepant diagnosis where treatment was not substantially altered. There was one case of discordant diagnosis where lymphoma was diagnosed and subsequently treated. The cost per discrepant diagnosis was $141,880 and per discordant diagnosis was $1,669 when using 100% Medicare reimbursement and Current Procedural Terminology (CPT) code combination 88304+88311. Conclusion: Histopathologic analysis of femoral head specimens in THAs showed an association with high costs given the rarity of discordant diagnoses. Routine use of the practice should be at the discretion of individual hospitals with consideration for cost and utility thresholds.

• Hip & pelvis
• /
• v.34 no.3
• /
• pp.185-190
• /
• 2022

Septic arthritis (SA) is a joint inflammation that develops secondary to infectious causes. SA in children is associated with a high rate of morbidity and mortality; therefore, it is regarded as an orthopedic emergency. Because SA of the hip joint usually mimics other musculoskeletal diseases, diagnosis remains challenging. Although this lesion usually shows a good outcome, treatment at an inappropriate time, neglect, or inadequate treatment could lead to poor outcomes. We report on the case of a healthy adolescent who complained of episodes of fever and chills, weight loss, pain in his left hip, and limping. After performing necessary workups, two differential diagnoses of tumor and SA were made. The results of Gram stain and culture of the synovial fluid after surgical excision showed Klebsiella pneumoniae and Enterobacter cloacae complex. To the best of our knowledge, this is the first report of SA due to co-infection with K. pneumoniae and E. cloacae in a healthy patient.

• Journal of Yeungnam Medical Science
• /
• v.15 no.2
• /
• pp.263-274
• /
• 1998

One of the main purposes in the treatment of developmental dislocation of the hip is to achieve and maintain concentric, congruent, and stable reduction. The arthrogram performs an important role in the diagnosis and treatment of developmental dislocation of the hip. The arthrogram provides much information about the soft tissue status of the hip joint. Limbus and ligamentum teres is exactly evaluated so that we can plan the reduction and treatment before operation. Eighteen preoperative hip arthrograms of 17 children treated for developmental dislocation of the hip from 1992 to 1998 were reviewed. The limbus, ligamentum teres and transverse acetabular ligament were compared with the pathoanatomy seen at the time of open reduction. Arthrography proved to be reliable in identifying the limbus and ligamentum teres. So we recommend that arthrography must be performed before closed or open reduction. Also, we recorded the radiographic parameters: acetabular index, acetabular floor thickness, center edge(CE) angle of Wiberg, and Y-coordinate. The center edge(CE) angle of Wiberg obtained from arthrography was measured more accurately than from simple roentgenograms because the ossification of the femoral head was frequently located eccentrically in the developmental dislocation of the hip.

• Journal of the Korean Orthopaedic Association
• /
• v.55 no.5
• /
• pp.359-365
• /
• 2020

Developmental dysplasia of the hip broadly includes inadequate development of the hip joint involving the acetabulum or proximal femur, or both. Although ultrasonographic studies in neonates have greatly lowered the frequency of neglected or operatively treated cases, its sensitivity is less than desired. Hip dysplasia without subluxation is commonly diagnosed incidentally and strongly related to degenerative arthritis in females after the 4th decade. Hip dysplasia with subluxation shows symptoms through various periods, depending on its severity, especially for women with onset during pregnancy. A complete physical examination and early treatment for neonates are extremely important for obtaining satisfactory outcomes. To avoid underdiagnosis and to serve appropriate treatment on time, the authors recommend examining any suspicious hips in infants under two years of age. The study will discuss the diagnosis and primary treatment of developmental dysplasia of the hip.

• Hip & pelvis
• /
• v.36 no.2
• /
• pp.87-100
• /
• 2024

Total hip arthroplasty (THA) is an effective treatment for osteoarthritis, and the popularity of the direct anterior approach has increased due to more rapid recovery and increased stability. Instability, commonly caused by component malposition, remains a significant concern. The dynamic relationship between the pelvis and lumbar spine, deemed spinopelvic motion, is considered an important factor in stability. Various parameters are used in evaluating spinopelvic motion. Understanding spinopelvic motion is critical, and executing a precise plan for positioning the implant can be difficult with manual instrumentation. Robotic and/or navigation systems have been developed in the effort to enhance THA outcomes and for implementing spinopelvic parameters. These systems can be classified into three categories: X-ray/fluoroscopy-based, imageless, and computed tomography (CT)-based. Each system has advantages and limitations. When using CT-based systems, preoperative CT scans are used to assist with preoperative planning and intraoperative execution, providing feedback on implant position and restoration of hip biomechanics within a functional safe zone developed according to each patient's specific spinopelvic parameters. Several studies have demonstrated the accuracy and reproducibility of robotic systems with regard to implant positioning and leg length discrepancy. Some studies have reported better radiographic and clinical outcomes with use of robotic-assisted THA. However, clinical outcomes comparable to those for manual THA have also been reported. Robotic systems offer advantages in terms of accuracy, precision, and potentially reduced rates of dislocation. Additional research, including conduct of randomized controlled trials, will be required in order to evaluate the long-term outcomes and cost-effectiveness of robotic-assisted THA.

• Hip & pelvis
• /
• v.34 no.4
• /
• pp.203-210
• /
• 2022

Purpose: Total hip arthroplasty (THA) using the direct anterior approach (DAA) is known to have a learning curve. The purpose of this study was to review cases where surgery was performed by an arthroplasty surgeon transitioning from the posterior approach (PA) to the DAA. We hypothesized similar complication rates and improvements in surgical duration over time. Materials and Methods: A review of 2,452 consecutive primary THAs was conducted. Surgical duration, length of stay (LOS), surgical complications, decrease in postoperative day (POD) 1 hemoglobin, transfusion rates, POD 0 and POD 1 pain scores, incision length, leg length discrepancy (LLD), and radiographic cup position were recorded. Results: No differences in surgical duration were observed after the first 50 DAA cases. A shorter LOS was observed for the DAA, and statistical difference was appreciated after the first 100 DAA cases. There were no differences in periprosthetic fractures. A higher rate of infections and hip dislocations were observed with the PA. The PA showed an association with higher transfusion rates without significant difference in POD 1 decrease in hemoglobin over the first 100 DAA cases. Similar POD 0 and POD 1 pain scores with a smaller incision were observed for the first 100 DAA cases. The DAA cohort showed less variation in cup inclination, version, and LLD. Conclusion: DAA is safe and non-inferior in terms of reduced LOS, smaller incision, and less variation in cup position. Fifty DAA cases was noted to be the learning curve required before no differences in duration between approaches were observed.

• Hip & pelvis
• /
• v.36 no.3
• /
• pp.211-217
• /
• 2024

Purpose: The concept of a superior approach (SA) involves the use of a tissue-sparing posterior approach (PA), with exposure of the piriformis muscle and gluteus medius/minimus muscles. The objective of this study was to clarify the features of hip hemiarthroplasty (HA) using a SA in regard to early recovery and mid-term outcomes, with a comparison of the outcomes of SA-HAs and HAs using a PA (PA-HAs). Materials and Methods: A total of 120 HAs for treatment of primary femoral neck fracture with a healthy opposite hip joint were performed in our hospital from 2013 to 2018. Propensity score matching in regard to age, sex, body mass index, walking ability before injury, place of residence, time to surgery, and American Society of Anesthesiologists-Physical Status was performed for 79 patients with SA-HAs and 41 patients with PA-HAs. The final analysis included 34 patients who underwent SA-HAs and 34 patients who underwent PA-HAs. Results: The duration of surgery was 57.1 minutes and 72.1 minutes (P=0.001) for SA-HAs and PA-HAs, respectively. The scores for walking ability at postoperative one week were 4.9±1.4 and 4.2±1.0 (P=0.021) for SA-HAs and PA-HAs, respectively. The Barthel index (BI) at the start of rehabilitation was 26.2±18.7 and 17.4±16.3 (P=0.042) for SA-HAs and PA-HAs, respectively. The 4-year complication-free survival rates were 74.2% and 56.3% for SA-HAs and PA-HAs, respectively (P=0.310). Conclusion: SA-HA can be performed without torsion of the muscles and ligaments around the hip joint. Early recovery of walking ability and BI was a significant feature of SA-HAs.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.37 no.7
• /
• pp.703-708
• /
• 2013

Conventional total hip joint replacement(THR) surgery requires a long incision and long rehabilitation time. The stem used in THR is inserted into the cancellous bone of the femur where it plays the role of the artificial joint. Minimally invasive surgery(MIS) has been devised to reduce muscle damage to patients. In this study, a mechanical stem was developed on the basis of MISto reduce the incision length through the principle of the gear. The mechanical stem consists of six components. A prototypical model for a mechanical stem was fabricated using an acryl-based polymer, and its workability was confirmed. To actualize the mechanical stem, a three-dimensional Bio-CAD modeling technique was applied. The hip joint area based on computed tomography(CT) was reconstructed. The safety of the mechanical stem by applying more load than the weight of a man under virtual surgery environment conditions was confirmed by finite element analysis.

• PNF and Movement
• /
• v.20 no.2
• /
• pp.295-306
• /
• 2022

Purpose: This study aimed to investigate the effect of robot-assisted gait training on the active ranges of motion, gait abilities, and biomechanical characteristics of gait in patients who underwent lower extremity surgery, and to verify the effectiveness and clinical usefulness of robot-assisted gait training. Methods: This study was conducted on 14 subjects who underwent lower extremity surgery. The subjects participated in robot-assisted gait training for 2 weeks. The active ranges of motion of the lower extremities were evaluated, and gait abilities were assessed using 10-m and 2-min walk tests. An STT Systems Inertial Measurement Unit was used to collect data on biomechanical characteristics during gait. Spatiotemporal parameters were used to measure cadence, step length, and velocity, and kinematic parameters were used to measure hip and knee joint movement during gait. Results: Significant improvements in the active ranges of motion of the hip and knee joints (flexion, extension, abduction, and adduction) and in the 10-m and 2-min walk test results were observed after robot-assisted gait training (p < 0.05). In addition, biomechanical characteristics of gait, spatiotemporal factors (cadence, step length, and velocity), and kinematic factors (gait hip flexion-extension, internal rotation-external rotation angle, and knee joint flexion-extension) were also significantly improved (p < 0.05). Conclusion: The results of this study are of clinical importance as they demonstrate that robot-assisted gait training can be used as an effective intervention method for patients who have undergone lower extremity surgery. Furthermore, the findings of this study are clinically meaningful as they expand the scope of robot-assisted gait training, which is currently mainly applied to patients with central nervous system conditions.