Bone Density Distribution Pattern in the Lateral Wall of the Femoral Intercondylar Notch: Implications for the Direct Insertion of the Femoral ACL Attachment.

Background: The ideal position of the femoral bone tunnel in the anterior cruciate ligament (ACL) is controversial. The functional importance of the ACL fiber varies depending on where it is attached to the femur. Functionally important fibers can cause high mechanical stress on the bone, and the Wolff law predicts that bone mineral density will increase at high mechanical stress sites. Purpose/Hypothesis: The purpose of this study was to use computed tomography imaging to determine the distribution pattern of bone density in the lateral intercondylar wall. It was hypothesized that the high-density area (HDA) of the lateral intercondylar wall would reflect the functional insertion of the ACL as reported in previous anatomic studies. Study Design: Descriptive epidemiology study. Methods: Data from 39 knees without ACL injuries were retrospectively collected. The HDA of the lateral intercondylar wall was defined as the region containing the top 10% of the radiodensity values. The shape of the HDA was approximated as an ellipse, and the quadrant method was used to determine the center of the ellipse. The association between the ratio of the minor axis to the major axis of the ellipse and background characteristics was investigated. Results: According to the quadrant method, the center of the HDA ellipse was 33.6% in the deep-shallow direction and 23.4% in the high-low direction. The center of the ellipse was comparable to the anatomic center of the ACL footprint, as previously reported. The ratio of the minor axis to the major axis of the ellipse was 0.58 (95% CI, 0.54-0.62). There was a significant negative correlation between the ratio of the minor axis to the major axis of the HDA ellipse and the posterior tibial slope (r = -0.38, P = .02). Conclusion: The center of the HDA ellipse was found to be similar to the anatomic center of the ACL footprint. Considering the mechanical stress responses in bone, the HDA of the lateral intercondylar wall has the potential to represent the ACL insertion, especially functional insertion.

Amputation surgery associated with shortened survival in patients with localized extremity bone sarcoma.

Background: This study assesses survival rates among patients with localized extremity bone sarcoma who have undergone amputation, pinpointing subpopulations that are disproportionately affected by amputation-related survival disparities. Methods: Examination of data was conducted using the Surveillance, Epidemiology, and End Results (SEER) program, analyzing records of 3765 patients diagnosed with localized extremity bone sarcoma between 2000 and 2019. Of these, 857 received amputations (Amputation cohort), and 2908 underwent limb-sparing surgeries. Propensity score matching, considering demographic and clinical features, was utilized to ensure a fair comparison. Results: Following propensity score matching, the study focused on 1714 cases. The Amputation cohort was observed to have significantly poorer survival rates (Cancer-Specific Survival [CSS]: Hazard Ratio [HR] = 1.28, 95% Confidence Interval [CI]: 1.05-1.55; Overall Survival [OS]: HR = 1.37, 95% CI: 1.15-1.63). Subsequent subgroup analysis indicated that individuals with tumors exceeding 8 cm in size or those located in the lower limbs were notably at a higher risk of shortened survival (for tumors >8 cm - CSS: HR = 1.32, 95% CI: 1.02-1.71; OS: HR = 1.39, 95% CI: 1.09-1.76; for lower limb tumors - CSS: HR = 1.25, 95% CI: 1.01-1.54; OS: HR = 1.33, 95% CI: 1.11-1.61). Conclusions: Our findings demonstrate that patients diagnosed with localized extremity bone sarcoma undergoing amputation exhibit lower survival rates, especially in cases involving tumors of greater size or those situated in the lower limbs. In patient groups where amputation is inevitable, careful follow-up is required after surgical intervention.

The alterations in nerve growth factor concentration in plasma and synovial fluid before and after total knee arthroplasty.

Total knee arthroplasty (TKA) is an effective procedure for pain relief; however, the emergence of postsurgical pain remains a concern. In this study, we investigated the production of nerve growth factor (NGF) and mediators that affect NGF production and their function in the synovial fluid and plasma after TKA. This study included 19 patients (20 knees) who had rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and knee osteoarthritis (OA) who underwent TKA, categorized into OA and non-OA groups. The levels of NGF, inflammatory cytokines, and lipid mediators were analyzed before and after surgery. The intraoperative synovial fluid NGF concentration was more than seven times higher in the non-OA group than in the OA group. The intra-articular NGF levels increased significantly by more than threefold postoperatively in the OA group but not in the non-OA group. Moreover, the levels of inflammatory cytokines and lipid mediators were increased in the synovial fluid of both groups. The intra-articular cytokines or NGF concentrations positively correlated with postoperative pain. Targeted NGF control has the potential to alleviate postsurgical pain in TKA, especially in patients with OA, emphasizing the importance of understanding NGF dynamics under different knee conditions.

Articular cartilage corefucosylation regulates tissue resilience in osteoarthritis.

This study aimed to investigate the glycan structural changes that occur before histological degeneration in osteoarthritis (OA) and to determine the mechanism by which these glycan conformational changes affect cartilage degeneration. An OA model was established in rabbits using mannosidase injection, which reduced high-mannose type N-glycans and led to cartilage degeneration. Further analysis of glycome in human OA cartilage identified specific corefucosylated N-glycan expression patterns. Inhibition of N-glycan corefucosylation in mice resulted in unrecoverable cartilage degeneration, while cartilage-specific blocking of corefucosylation led to accelerated development of aging-associated and instability-induced OA models. We conclude that α1,6 fucosyltransferase is required postnatally to prevent preosteoarthritic deterioration of articular cartilage. These findings provide a novel definition of early OA and identify glyco-phenotypes of OA cartilage, which may distinguish individuals at higher risk of progression.

Surgical Resection of Primary Tumor for Bone Metastatic Breast Cancer Patients at Initial Presentation.

BACKGROUND/AIM: The purpose of this study was to investigate whether primary tumor resection in patients with bone metastatic breast cancer has an impact on survival using the Surveillance, Epidemiology, and End Results database, considering subtype classification. PATIENTS AND METHODS: We included all female patients with bone metastatic breast cancer at initial presentation between 2010 and 2016 with known hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) statuses. Cases showing unknown cause of death or unknown HR/HER2 status were excluded. Survival analysis was performed using Cox proportional hazards modeling to calculate hazard ratios (HZR). RESULTS: Of the 13,450 patients included in this study, 2,073 patients were HR+/HER2+, 8,597 patients were HR+/HER2-, 797 patients were HR-/HER2+, and 1,182 patients were HR-/HER2- (triple-negative). Five-year overall survival (OS) rate was 34.5% in HR+/HER2+, 26.0% in HR+/HER2-, 29.2% in HR-/HER2+ and 8.0% in triple-negative. Triple-negative patients showed the worsen OS [HR+/HER2+: HZR=2.1, 95% confidence interval (CI)=1.9-2.3; HR+/HER2-: HZR= 2.4, 95%CI=2.2-2.6; HR-/HER2+: HZR=1.5, 95%CI=1.3-1.6]. After excluding patients who died within six months, primary tumor resection prolonged survival in each subtype classification except HR-/HER2+. CONCLUSION: Patients with triple-negative bone metastatic breast cancer showed unfavorable survival. Primary tumor resection prolonged survival in each subtype except for HR-/HER2+.

Bone metastatic cancer of unknown primary at initial presentation

Introduction Cancer of unknown primary (CUP) is a challenging malignancy. The purpose of this study was to investigate the clinical characteristics and prognosis of bone metastatic CUP using the population-based Surveillance, Epidemiology, and End Results (SEER) database. Methods From the SEER database, we identified 1908 patients with bone metastatic CUP at initial presentation between 2010 and 2018. Histology was subdivided following International Classification of Diseases for Oncology codes as Adenocarcinoma, Squamous cell, Neuroendocrine, or Carcinoma not otherwise specified (NOS). Cox proportional hazard modeling was applied using factors of age, sex, ethnicity, histological subtype, and therapeutic intervention. Results Among the 1908 patients, histology was Neuroendocrine in 240 patients, Squamous cell in 201 patients, Adenocarcinoma in 810 patients and NOS in 657 patients. In each subtype, patients tended to be predominantly male and white. Chemotherapy was introduced for 28% of patients and radiation for 34% in the entire cohort. Survival in patients with bone metastatic CUP was unfavorable, with a median survival of 2 months. Among the histological subtypes, Adenocarcinoma showed shorter survival than the other groups. In addition, treatment interventions such as chemotherapy and radiation therapy prolonged survival, particularly for Squamous cell, Adenocarcinoma and NOS, but not for Neuroendocrine. Discussion Bone metastatic CUP showed extremely poor prognosis, but treatment interventions such as chemotherapy and radiation generally offered survival benefits. Further randomized clinical research is needed to confirm the present results (AU)

Bone metastatic cancer of unknown primary at initial presentation.

INTRODUCTION: Cancer of unknown primary (CUP) is a challenging malignancy. The purpose of this study was to investigate the clinical characteristics and prognosis of bone metastatic CUP using the population-based Surveillance, Epidemiology, and End Results (SEER) database. METHODS: From the SEER database, we identified 1908 patients with bone metastatic CUP at initial presentation between 2010 and 2018. Histology was subdivided following International Classification of Diseases for Oncology codes as Adenocarcinoma, Squamous cell, Neuroendocrine, or Carcinoma not otherwise specified (NOS). Cox proportional hazard modeling was applied using factors of age, sex, ethnicity, histological subtype, and therapeutic intervention. RESULTS: Among the 1908 patients, histology was Neuroendocrine in 240 patients, Squamous cell in 201 patients, Adenocarcinoma in 810 patients and NOS in 657 patients. In each subtype, patients tended to be predominantly male and white. Chemotherapy was introduced for 28% of patients and radiation for 34% in the entire cohort. Survival in patients with bone metastatic CUP was unfavorable, with a median survival of 2 months. Among the histological subtypes, Adenocarcinoma showed shorter survival than the other groups. In addition, treatment interventions such as chemotherapy and radiation therapy prolonged survival, particularly for Squamous cell, Adenocarcinoma and NOS, but not for Neuroendocrine. DISCUSSION: Bone metastatic CUP showed extremely poor prognosis, but treatment interventions such as chemotherapy and radiation generally offered survival benefits. Further randomized clinical research is needed to confirm the present results.

Atelocollagen-associated autologous chondrocyte implantation for the repair of large cartilage defects of the knee: Results at three to seven years.

BACKGROUND: Recently, various types of engineered autologous chondrocyte implantation (ACI) have been developed. Atelocollagen-associated ACI (A-ACI) is the only ACI procedure covered by Japanese Health Insurance since 2013. The indications of the A-ACI are traumatic cartilage defects and osteochondral dissecans (OCD) for knee joints. PURPOSE: To evaluate midterm clinical results after A-ACI for the treatment for full-thickness cartilage defects of the knee. METHODS: Thirteen consecutive patients who underwent A-ACI between 2014 and 2018 had been prospectively enrolled in this study. There were 11 men and 2 women with a mean age of 34 years at the time of surgery. The causes of the cartilage defect were trauma in 10 knees and OCD in 3 knees. The total number of lesions was 15, which were comprised of the medial femoral condyle in 5 knees, the lateral femoral condyle in 5 knees, and the femoral trochlea in 5 knees. The mean size of the lesion was 5.3 cm2. Each knee was clinically and radiologically evaluated preoperatively and postoperatively. RESULTS: The mean Lysholm score improved significantly from 74.0 points to 94.0 points (p = 0.008) and each subscale in Knee injury and Osteoarthritis Outcome Score improved significantly (p < 0.001) at the mean final follow-up period of 51 months (range, 36-84 months). The magnetic resonance observation of cartilage repair tissue 2.0 score at the mean follow-up of 38 months was significantly higher than that at 2 months postoperatively (p = 0.014). According to the International Cartilage Repair Society (ICRS) grading scale, 3 knees were graded as normal, 3 knees as nearly normal, and 1 knee as severely abnormal in second-look arthroscopic evaluation at a mean of 22 months (range, 8-41 months) after A-ACI. CONCLUSION: The present study showed a significant subjective and objective clinical improvement in the A-ACI for large cartilage defects of the knee at a mean follow-up of 51 months (range, 36-84 months).

Effect of Patient Age on Clinical and Radiological Outcomes After Medial Open-Wedge High Tibial Osteotomy: A Comparative Study With 344 Knees.

Background: There exists some controversy regarding whether patient age is a predictive factor for outcomes after high tibial osteotomy (HTO). Purpose/Hypothesis: The purpose of this study was to evaluate whether patient age affects clinical and radiological outcomes after medial open-wedge HTO (OWHTO) in a large population with a wider age range than previous studies. It was hypothesized that there would be no differences in outcomes when compared across age-groups. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective comparative study was conducted using 344 patients (303 knees) who underwent OWHTO from 2009 to 2018. These patients were divided into 3 groups based on age at the time of surgery: ≥55 years (group Y: 76 knees in 57 patients), 56 to 64 years (group M: 129 knees in 120 patients), and ≤65 years (group O: 139 knees in 126 patients). Clinical and radiological evaluations were performed immediately before surgery and at the final follow-up period, at a mean of 5.1 years (range, 3-11 years). Comparisons among the 3 groups were conducted with 1-way analysis of variance for continuous variables. When a significant result was obtained, a post hoc test with Bonferroni correction was conducted for multiple comparisons. Results: In clinical evaluations, there were no significant differences among the 3 groups either preoperatively or postoperatively concerning the Japanese Orthopaedic Association score, the Lysholm score, or the Knee injury and Osteoarthritis Outcome Score (KOOS), with the exception of the preoperative KOOS Symptoms subscale, which was significantly higher in group Y versus group O (48.9 ± 18.7 vs 58.7 ± 15.4, respectively; P = .011). The Tegner activity score was significantly different among the groups, both preoperatively and postoperatively (P < .001 for both). There was no significant difference in the occurrence of complications or the survival rate at final follow-up among the 3 groups. Conclusion: The study findings suggest that patient age does not affect clinical and radiological outcomes after OWHTO.

Symptomatic bilateral complete discoid medial menisci of the knee in a child: A case report.

Bilateral complete discoid medial menisci are extremely rare congenital anatomic variants of the knee. Currently, arthroscopic partial meniscectomy with or without peripheral suture repair is performed for symptomatic discoid meniscus. However, most of the outcomes are short-term. In this article, we present a pediatric case of symptomatic bilateral complete discoid medial menisci and highlight the effectiveness of arthroscopic partial meniscectomy with or without peripheral suture on symptomatic complete discoid medial menisci based on 60-month excellent clinical and functional results.

Single-step ultra-purified alginate gel implantation in patients with knee chondral defects.

Aims: Implantation of ultra-purified alginate (UPAL) gel is safe and effective in animal osteochondral defect models. This study aimed to examine the applicability of UPAL gel implantation to acellular therapy in humans with cartilage injury. Methods: A total of 12 patients (12 knees) with symptomatic, post-traumatic, full-thickness cartilage lesions (1.0 to 4.0 cm2) were included in this study. UPAL gel was implanted into chondral defects after performing bone marrow stimulation technique, and assessed for up to three years postoperatively. The primary outcomes were the feasibility and safety of the procedure. The secondary outcomes were self-assessed clinical scores, arthroscopic scores, tissue biopsies, and MRI-based estimations. Results: No obvious adverse events related to UPAL gel implantation were observed. Self-assessed clinical scores, including pain, symptoms, activities of daily living, sports activity, and quality of life, were improved significantly at three years after surgery. Defect filling was confirmed using second-look arthroscopy at 72 weeks. Significantly improved MRI scores were observed from 12 to 144 weeks postoperatively. Histological examination of biopsy specimens obtained at 72 weeks after implantation revealed an extracellular matrix rich in glycosaminoglycan and type II collagen in the reparative tissue. Histological assessment yielded a mean overall International Cartilage Regeneration & Joint Preservation Society II score of 69.1 points (SD 10.4; 50 to 80). Conclusion: This study provides evidence supporting the safety of acellular UPAL gel implantation in facilitating cartilage repair. Despite being a single-arm study, it demonstrated the efficacy of UPAL gel implantation, suggesting it is an easy-to-use, one-step method of cartilage tissue repair circumventing the need to harvest donor cells.

Amputation surgery associated with shortened survival in patients with localized soft tissue sarcoma.

BACKGROUND: The objectives of this study were to clarify whether localized extremity soft tissue sarcoma (STS) patients who underwent amputation surgery experienced worsened survival and to identify those patients for whom amputation surgery worsened survival. METHODS: Using the Surveillance, Epidemiology, and End Results database, we identified 8897 patients with localized extremity STS between 1983 and 2016. Of these 6431 patients, 733 patients underwent amputation surgery (Amputation group), and 5698 underwent limb-sparing surgery (Limb-sparing group). RESULTS: After adjusting for patient background by propensity score matching, a total of 1346 patients were included. Patients in the Amputation group showed worsened survival (cancer-specific survival (CSS): hazard ratio (HR) = 1.42, 95% confidence interval (CI) 1.15-1.75, overall survival (OS): HR = 1.41, 95%CI 1.20-1.65). In subclass analysis, patients with high-grade STS, spindle cell sarcoma and liposarcoma in the Amputation group showed shortened survival (high-grade-CSS: HR = 1.44, 95%CI 1.16-1.77, OS: HR = 1.38, 95%CI 1.18-1.62; spindle cell sarcoma-CSS: HR = 4.75, 95%CI 1.56-14.4, OS: HR = 2.32, 95%CI 1.45-3.70; liposarcoma-CSS: HR = 2.91, 95%CI 1.54-5.50, OS: HR = 2.32, 95%CI 1.45-3.70). CONCLUSIONS: Survival was shortened in localized extremity STS patients who received amputation surgery.

Three-stage total knee arthroplasty combined with deformity correction and leg lengthening using Taylor spatial frames and conversion to internal fixation for severe intra- and extra-articular deformities and hypoplasia in a patient with hemophilic knee arthropathy: A case report.

BACKGROUND: Hemophilic arthropathy is a cause of severe knee deformity, because chronic synovitis due to repeated hemarthrosis affects the area of the epiphyseal plates in juvenile cases. Total knee arthroplasty (TKA) is the standard treatment for end-stage knee arthropathy. However, it is difficult to perform one-stage TKA in patients with severe intra- and extra-articular deformities. CASE PRESENTATION: We reported a case of hemophilic arthropathy in a 55-year-old male with leg length discrepancy of 4 cm, limited range of knee motion (-40° extension and 85° flexion), intra-articular deformity (medial proximal tibial angle: 69°; mechanical lateral distal femoral angle: 79°), extra-articular deformity at the distal femoral metaphyseal (30° valgus and 45° flexion deformity), and varus malalignment (% mechanical axis: 33%). We planned a three-stage TKA. Firstly, we performed gradual correction and lengthening of the distal femur using Taylor spatial flame. Six months after surgery, we performed conversion surgery from external fixation to internal fixation. Finally, we performed TKA with rotating hinged type implant. Two years after surgery, physical examination showed a normal gait, leg length discrepancy of 2 cm (the right leg was shorter), improvement in the range of knee motion (0° extension and 100° flexion). CONCLUSION: To the best of our knowledge, this presents the first combination of three-stage TKA with correction of femoral deformity and leg lengthening using a Taylor spatial frame and conversion to internal fixation in a patient with hemophilic knee arthropathy and severe intra- and extra-articular deformities.

Occurrence Rate of Cyclops Lesion After Anatomic Double-Bundle ACL Reconstruction: Comparison Between Remnant Tissue Preservation and Resection Methods.

Background: The occurrence rate of cyclops lesion after anatomic double-bundle anterior cruciate ligament (ACL) reconstruction with remnant tissue preservation remains unclear. Hypothesis: The study hypotheses were as follows: (1) the occurrence rate of cyclops lesion will be comparable between the remnant-preserving and remnant-resecting ACL reconstruction methods, and (2) there will be no significant differences in clinical outcomes between the remnant-preserving and remnant-resecting procedures. Methods: This retrospective comparative study involved 177 patients who underwent unilateral anatomic double-bundle ACL reconstruction using hamstring tendon autografts from 2014 to 2018 at our hospital. According to the Crain classification of ACL remnant tissue, 98 patients with remnant types I, II, or III underwent the remnant-preserving procedure (group A), and the remaining 79 patients with remnant type IV underwent the remnant-resecting procedure (group B). All patients underwent second-look arthroscopy. Patients were evaluated according to arthroscopic and clinical results at postoperative 15.2 ± 8.4 months (mean ± SD). Statistical comparisons between groups were made using the paired Student t test, chi-square test, and Fisher exact test. Study Design: Cohort study; Level of evidence, 3. Results: At second-look arthroscopy, the incidence of cyclops lesions was significantly higher in group B than in group A (29.1% vs 13.3%; P = .0139). Cyclops lesions were divided into 4 locations: femoral side (type 1), midsubstance (type 2), tibial side (type 3), and anterior (type 4) of the ACL graft. The ratio of the tibial-side cyclops lesion (type 3) was significantly higher in group B than in group A (P = .0354). There were no significant differences in the clinical evaluation scores between the procedures. Side-to-side anterior laxity was significantly less in group A than in group B (0.7 vs 1.6 mm; P = .0035). Concerning postoperative laceration and synovium coverage of the grafts, group A was significantly better than group B (P < .0001). Conclusion: In this cohort of patients undergoing double-bundle ACL reconstruction, resection of the ACL remnant was associated with a significantly higher rate of cyclops lesion formation when compared with preservation of the remnant.

Comparison of clinical features between patients with bone and soft tissue fibrosarcomas.

BACKGROUND AND OBJECTIVES: Fibrosarcomas predominantly arise in soft tissues, but can also develop in bone. Because of their rarity, whether bone development has an impact on clinical features has not been addressed. METHODS: We included fibrosarcoma patients diagnosed between 1983 and 2016 in the Surveillance, Epidemiology, and End Results database. Differences in clinical features between fibrosarcoma of bone (FS-B) and fibrosarcoma of soft tissue (FS-ST) were investigated. RESULTS: After excluding patients without information regarding cause of death, site of origin, distant tumor or survival, 1443 patients were included. Of those, 98 patients had FS-B. Patients with FS-B were younger, more frequently male, with fibrosarcomas that more often developed in an extremity and were histologically high-grade. In contrast, no difference in potential to metastasize was observed. Survival was almost equal between FS-B and FS-ST (FS-B/FS-ST: cancer-specific survival, hazard ratio [HR]: 1.2, 95% confidence interval [CI]: 0.8-1.7; overall survival, HR: 1.3, 95% CI: 0.9-1.7). CONCLUSIONS: Our results clearly indicated that patient backgrounds differed, such as younger age and greater tendencies to affect males, develop in an extremity and show high-grade tumor in patients with FS-B. In contrast, no differences were observed in distant metastatic potential or survival.

Liver metastasis in soft tissue sarcoma at initial presentation.

BACKGROUND AND OBJECTIVES: Noncontrast computed tomography of the chest is the standard imaging modality for cancer staging in patients with soft tissue sarcoma (STS), but appropriate candidates for liver screening have not been clarified. METHODS: We reviewed all patients with STS diagnosed between 2010 and 2018 in the Surveillance, Epidemiology, and End Results database. Incidence of liver metastasis at initial presentation and high incidence of liver metastasis by histological subtype were investigated. In addition, risk factors for liver metastasis were investigated by multiple logistic regression analysis. RESULTS: After excluding patients without information about liver metastasis, cause of death or primary liver tumor, 47 260 patients were included in this study. Of those, 1471 patients (3.2%) showed liver metastasis at initial presentation. The histological subtype showing the highest incidence of liver metastasis was desmoplastic small round cell tumor (30.3%), followed by malignant hemangioendothelioma (11.5%) and angiomyoliposarcoma (10.5%). Deep-rooted tumor, location in the body wall, retroperitoneum, or thorax/peritoneum, high histological grade, and higher T stage were associated with higher incidences of liver metastasis at initial presentation. CONCLUSION: Risk factors for liver metastasis were deep location, trunk development, larger tumor size, high histological grade, and specific histological subtypes.

Effect of the Inverted V-Shaped Osteotomy on Patellofemoral Joint and Tibial Morphometry as Compared With the Medial Opening Wedge High Tibial Osteotomy.

BACKGROUND: Recent studies have reported that medial opening wedge (OW) high tibial osteotomy (HTO) induces patella baja, resulting in degenerative changes in the patellofemoral joint. We have developed an inverted V-shaped (iV) HTO, which is classified as a neutral wedge osteotomy. HYPOTHESES: The study hypotheses were as follows: (1) patellar height, posterior tibial slope, and tibial length will not change between pre- and postoperative evaluations after iV-HTO; (2) the lateral shift ratio of the patella and the distance between the tibial tubercle and the trochlear groove may be significantly decreased after iV-HTO. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 191 patients (220 knees) who underwent HTO for medial osteoarthritis were enrolled retrospectively in this study: 107 knees underwent OW-HTO and 113 knees underwent iV-HTO. Clinical and radiological evaluations were performed before and at least 3 years after surgery. RESULTS: Postoperatively, the mean Caton-Deschamps ratio was significantly decreased (P < .0001) from 0.95 to 0.79 in the OW group, while there were no significant changes in the iV group. The mean posterior tibial slope was significantly increased (P < .0001) from 8.5° to 10.5° in the OW group, while there were no significant differences in the iV group. Although the entire leg length was significantly increased (P < .0003) in both groups after HTO, there were no significant differences in tibial length between the pre- and postoperative periods in the iV group. Regarding the congruity of the patellofemoral joint, the mean lateral shift ratio did not significantly change in the OW group, whereas it was significantly decreased (P = .0012) from 11.5% to 8.8% in the iV group. The mean tibial tubercle-trochlear groove distance was significantly decreased (P < .0001) from 12.8 to 9.7 mm in the iV group, while it was significantly increased in the OW group (P < .0001). Concerning the clinical outcome, the Japanese Orthopaedic Association (JOA) and Lysholm knee scores at final follow-up (OW vs iV: JOA, 91.2 vs 90.1; Lysholm, 92.5 vs 89.0) were significantly increased (P < .0001) as compared with the preoperative values (OW vs iV: JOA, 68.3 vs 66.8; Lysholm, 67.9 vs 61.0). CONCLUSION: Patellar height, posterior tibial slope, and tibial length did not change after the iV-HTO, while they were significantly changed after the OW-HTO. Although the preoperative degrees of varus knee and patellofemoral osteoarthritis were more severe in the iV group than the OW group, the iV-HTO led to altered patellofemoral joint congruity.

Does Primary Tumor Resection in Patients with Metastatic Primary Mobile Vertebral Column Sarcoma Improve Survival?

BACKGROUND: Primary mobile vertebral column sarcoma is an exceedingly rare malignancy. Although primary tumor resection has been reported to prolong survival in patients with metastatic bone sarcoma, whether primary tumor resection in patients with advanced primary mobile vertebral column sarcoma is associated with survival remains unclear owing to the rarity of this pathological entity. METHODS: Using the Surveillance, Epidemiology, and End Results database, 182 patients with metastatic primary mobile vertebral column sarcoma were identified between 1983 and 2015. Of the 182 patients enrolled, 101 patients (55%) underwent primary tumor resection (Surgery group) and 81 patients (45%) did not undergo resection (No Surgery group). To account for imbalances in the basic characteristics of patients between groups, propensity score matching was performed. Survival analysis was performed by weighted Cox proportional hazards modeling to calculate hazard ratios. RESULTS: After adjusting for patient background characteristics, 138 patients were included for the analysis (Surgery group: 69 patients; No Surgery group: 69 patients). The Surgery group did not show improved cancer-specific survival (hazard ratio = 0.73, 95% CI 0.49-1.10). Similarly, the Surgery group did not show improved overall survival compared with the No Surgery group (hazard ratio = 0.80, 95% CI 0.55-1.16). CONCLUSIONS: To our knowledge, this is the first study to indicate that surgical resection for advanced primary mobile vertebral column sarcoma does not have a positive impact on survival.