Background: A novel simplified navigation-based instrumentation system has been developed. It simplifies the existing navigation system and facilitates convenient bone cutting by positioning the tracker on an existing cutting block without additional pin fixation. This study aimed to compare the outcomes of this newly developed simplified navigation-based instrumentation system in primary total knee arthroplasty (TKA) performed by a novice surgeon with those of conventional surgical techniques. Methods: From January 2020 to July 2020, 67 knees that underwent primary TKA using the ExactechGPS TKA Plus (group A) were compared to 68 knees that underwent primary TKA using a conventional technique (group B). All patients had a minimum follow-up of 24 months. The operative details such as tourniquet time were investigated. Postoperative hip-knee-ankle (HKA) angle and component position angles in the coronal and sagittal planes (α, β, γ, and δ angles) were evaluated. The outlier rates were compared between the groups as those lying outside ± 3°. Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, the Western Ontario and McMaster Universities Osteoarthritis Index for pain and function, and range of motion were compared. Results: There was no statistically significant difference in average tourniquet time between the groups (74.3 vs. 70.3 minutes, p = 0.061). Outlier rates for HKA angle (7.5% vs. 23.5%, p = 0.010) and β angle (1.5% vs. 22.1%, p < 0.001) in group A were significantly lower than those in group B. There were no significant differences in clinical outcomes between the groups. Conclusions Primary TKA performed by a novice surgeon using a simplified navigation-based instrumentation system did not significantly increase the operation time, and more accurate lower extremity mechanical alignment and tibial component alignment in the coronal plane could be obtained.

Purpose: Although proximal femoral nail antirotation (PFNA; Synthes, Switzerland) has demonstrated satisfactory results when used for the treatment of intertrochanteric fractures, mechanical complications may occur. To better quantify the risk of mechanical complications when proximal femoral nail antirotation is used to treat intertrochanteric fractures, this study aimed to: (1) characterize the frequency of mechanical complications and extent of blade sliding and their correlation with reduction quality and (2) identify factors associated with mechanical complications. Materials and Methods: A review of medical records from 93 patients treated for intertrochanteric fractures with a minimum of 6-months of follow-up between February 2014 and February 2019 was conducted. Blade position was evaluated using Tip-apex distance (TAD) and Cleveland index. The extent of blade sliding was evaluated using the adjusted Doppelt’s method for intramedullary nailing. Individuals were classified as having or not having mechanical complications, and reduction quality and radiologic outcomes were compared between the two groups. Results: Mechanical complications occurred in 12 of 94 hips (12.8%), with 11 out of 12 being from the intramedullary reduction group. There was no significant difference in TAD between groups; however, there were significant differences were noted in Cleveland index, AO/OTA classification, reduction quality and extent of blade sliding. The mean blade sliding distance was 1.17 mm (anatomical group), 3.28 mm (extramedullary group), and 6.11 mm (intramedullary group), respectively (P<0.001). Data revealed that blade sliding was an associated factor for mechanical complications (odds ratio 1.25, 95% confidence interval 1.03-1.51). Conclusion The extent of blade sliding determined using the adjusted Doppelt’s method was significantly associated with mechanical complications suggesting that prevention of excessive sliding through proper intraoperative reduction is important to help achieve satisfactory treatment outcomes.

Mesenchymal stem cells (MSCs) are emerging as an attractive option for osteoarthritis (OA) of the knee joint, due to their marked disease-modifying ability and chondrogenic potential. MSCs can be isolated from various organ tissues, such as bone marrow, adipose tissue, synovium, umbilical cord blood, and articular cartilage with similar phenotypic characteristics but different proliferation and differentiation potentials. They can be differentiated into a variety of connective tissues such as bone, adipose tissue, cartilage, intervertebral discs, ligaments, and muscles. Although several studies have reported on the clinical efficacy of MSCs in knee OA, the results lack consistency. Furthermore, there is no consensus regarding the proper cell dosage and application method to achieve the optimal effect of stem cells. Therefore, the purpose of this study is to review the characteristics of various type of stem cells in knee OA, especially MSCs. Moreover, we summarize the clinical issues faced during the application of MSCs.

Osteotomy around the knee is a widely considered surgical procedure for osteoarthritis with lower extremity malalignment. High tibial osteotomy (HTO) is performed for varus deformity, while distal femur osteotomy (DFO) is performed for valgus deformity. However, if the correction is insufficient, double osteotomy can also be considered. This report included the basic principles and current concepts of patient selection and preoperative planning in osteotomy around the knee.
Congenital Abnormalities ; Femur ; Knee Joint ; Knee* ; Lower Extremity ; Osteoarthritis ; Osteotomy* ; Patient Selection

PURPOSE: The purpose of this study is to compare the clinical and radiographic outcomes of high tibial osteotomy (HTO) and unicompartmental arthroplasty (UKA) in advanced medial compartment arthritis accompanied by kissing lesions in relatively young patients. MATERIALS AND METHODS: Forty-five patients were divided into the HTO (n=23) and UKA (n=22) groups. Clinically, we evaluated the Lysholm knee scoring scale, visual analogue scale, Hospital for Special Surgery, and Western Ontario and McMaster Universities Osteoarthritis index scores preoperatively, 6 and 12 months postoperatively, and at the final follow-up. Radiographically, we measured the femoral-tibial angle and mechanical axis deviation preoperatively and at the final follow-up. RESULTS: All clinical outcomes gradually improved in both groups from the postoperative period to the final follow-up. At the final follow-up, all clinical outcomes were slightly better in the UKA group than in the HTO group; however, differences were not statistically significant. CONCLUSIONS: HTO is comparable to UKA in terms of clinical outcomes. Thus, the results of this study suggest that HTO might be a good alternative treatment to UKA for medial unicompartmental arthritis accompanied by kissing lesions in relatively young patients.
Arthritis ; Arthroplasty ; Arthroplasty, Replacement, Knee ; Follow-Up Studies ; Humans ; Knee ; Lysholm Knee Score ; Ontario ; Osteoarthritis ; Osteotomy ; Postoperative Period

PURPOSE: The purpose of this study is to compare the accuracy of the GNRB arthrometer (Genourob), Lachman test, and Telos device (GmbH) in acute anterior cruciate ligament (ACL) injuries and to evaluate the accuracy of each diagnostic tool according to the length of time from injury to examination. MATERIALS AND METHODS: From September 2015 to September 2016, 40 cases of complete ACL rupture were reviewed. We divided the time from injury to examination into three periods of 10 days each and analyzed the diagnostic tools according to the time frame. RESULTS: An analysis of the area under the curve (AUC) of a receiver operating characteristic curve showed that all diagnostic tools were fairly informative. The GNRB showed a higher AUC than other diagnostic tools. In 10 cases assessed within 10 days after injury, the GNRB showed statistically significant side-to-side difference in laxity (p<0.001), whereas the Telos test and Lachman test did not show significantly different laxity (p=0.541 and p=0.413, respectively). CONCLUSIONS: All diagnostic values of the GNRB were better than other diagnostic tools in acute ACL injuries. The GNRB was more effective in acute ACL injuries examined within 10 days of injury. The GNRB arthrometer can be a useful diagnostic tool for acute ACL injuries.
Anterior Cruciate Ligament ; Area Under Curve ; Diagnosis ; Knee ; ROC Curve ; Rupture

PURPOSE: This study is to investigate clinical and radiological results of staged treatment using a temporary external fixator in bicondylar tibial plateau fractures (TPFs) and to evaluate correlation between prognostic factors and postoperative clinical outcomes. MATERIALS AND METHODS: Twenty-four bicondylar TPF patients were selected. All patients were operated by a temporary external fixator first and then open reduction and internal fixation with dual plating. Clinical and radiological outcomes were evaluated. RESULTS: The mean American Knee Society score (AKSS) was 85.3. The mean Western Ontario and McMaster Universities Osteoarthritis index was 11.2. The mean range of motion (ROM) was 123.4°. The mean medial tibial plateau angle (mTPA) was 88.3°, and the mean proximal posterior tibial angle (PPTA) was 8.4°. Compared with the uninjured limb, the mean difference of mTPA was 1.5° and that of PPTA was 4.0°. The difference of PPTA and the AKSS demonstrated negative correlation (p=0.007). Patients with normal mTPA showed better ROM than those with abnormal mTPA (p=0.041). CONCLUSIONS: Staged treatment using a temporary external fixator in bicondylar TPFs showed good clinical and radiological outcomes. Surgeons should evaluate the reduction status intraoperatively by fluoroscopy and also refer to the uninjured limb radiologically.
External Fixators ; Extremities ; Fluoroscopy ; Humans ; Knee ; Ontario ; Osteoarthritis ; Range of Motion, Articular ; Surgeons ; Tibia

Non-union is one of the most devastating complications after fracture fixation. It usually results in prolonged treatment duration and unpredictable results. We reviewed the literature to identify recent information regarding the following: risk factors of nonunion; mechanical risk factors, including fracture gap width and stability, osteonecrosis and healing mechanism, osteoporotic fracture and fixation method, the characteristics of fracture, soft tissue injury, local infection, and multiple fractures; as well as the metabolic risk factors, including age, comorbidities, smoking, alcoholism, and medications. The technique and devices for fracture treatment have been developed, and treatments of nonunion are evolving according to the enhancement of our understanding of nonunion. Clinicians should refer to the risk factors and advancements while developing a treatment plan.
Alcoholism ; Comorbidity ; Fracture Fixation ; Fractures, Multiple ; Methods ; Osteonecrosis ; Osteoporotic Fractures ; Risk Factors ; Smoke ; Smoking ; Soft Tissue Injuries

Non-union is one of the most devastating complications after fracture fixation. It usually results in prolonged treatment duration and unpredictable results. We reviewed the literature to identify recent information regarding the following: risk factors of nonunion; mechanical risk factors, including fracture gap width and stability, osteonecrosis and healing mechanism, osteoporotic fracture and fixation method, the characteristics of fracture, soft tissue injury, local infection, and multiple fractures; as well as the metabolic risk factors, including age, comorbidities, smoking, alcoholism, and medications. The technique and devices for fracture treatment have been developed, and treatments of nonunion are evolving according to the enhancement of our understanding of nonunion. Clinicians should refer to the risk factors and advancements while developing a treatment plan.
Alcoholism ; Comorbidity ; Fracture Fixation ; Fractures, Multiple ; Methods ; Osteonecrosis ; Osteoporotic Fractures ; Risk Factors ; Smoke ; Smoking ; Soft Tissue Injuries

PURPOSE: The aim of this study was to investigate the utility of percutaneous wiring in the reduction of reverse oblique trochanteric fractures (AO classification 31-A3.3) by analyzing the treatment results with or without the use of percutaneous wiring. MATERIALS AND METHODS: Thirty-five cases from January 2008 to August 2014 that could be followed-up for at least one year were selected among patients with unstable trochanteric fractures who underwent either internal fixation or open reduction. Seventeen patients underwent surgery with percutaneous wire fixation but another 18 patients underwent surgery without it. All patients received a closed reduction and internal fixation with an intramedullary nail. The factors evaluated were as follows: the length of operation, loss of blood, length of in-hospital stay, lower limb function scale, return to preinjury daily life, change in femur neck shaft angle, postoperative gap of the fracture site, time taken for bone attachment, quality of post-operative reduction, and complications. RESULTS: No significant difference in the mean operative time, loss of blood, length of in hospital stay, lower limb function scale, return to pre-injury daily life, change in femur neck shaft angle, postoperative gap of the fracture site, and quality of postoperative reduction was observed between the two groups. A significant difference was noted in the time taken for bone attachment (p=0.032). Bone attachment took 13.3 weeks (9–17 weeks) on average when fixed with percutaneous wiring and no patient was found to have any complications. When treated without percutaneous wiring, however, bone attachment took 17.8 weeks (12.5–28.0 weeks) on average and three cases resulted in delayed union. CONCLUSION: Percutaneous wiring is a recommended treatment option for patients with an unstable trochanteric fracture.
Classification* ; Femur Neck ; Femur* ; Fractures, Comminuted ; Hip Fractures* ; Humans ; Length of Stay ; Lower Extremity ; Operative Time