Posterior Slope Angle Research Articles

Radiographic Assessment of Total Knee Arthroplasty Alignment with and without Accelerometer-Based Navigation at a Resident Training Institution.

Malalignment and lack of surgeon experience are cited as risk factors for prosthetic failure and the need for subsequent revision surgery in total knee arthroplasty (TKA). Various Conventional (CON) and Computer Assisted Surgical (CAS) methods have been developed to try and prevent malalignment and limit outliers. One of these methods is through an accelerometer-based CAS (aCAS) which intra-operatively helps determine the angulation and amount of resection necessary to restore alignment in TKA. The purpose of this study was to determine the number of TKA alignment outliers in TKA's performed both with CON and aCAS methods at a single training institution in cases that trainees were involved in. In this retrospective single center study, radiographic analysis of 150 primary TKAs performed at our training institution was performed. The medial distal femoral angle (DFA), medial proximal tibial angle (PTA), and posterior slope angle (PSA) were evaluated on immediate post-operative radiographs of 75 aCAS and 75 CON knees. Outlier measurements were defined as DFA outside of 5° ±3° valgus; PTA >±3° from neutral axis; and PSA outside 0-7° for Cruciate Retaining (CR) and 0-5° for Posterior Stabilized (PS) implants. Data was analyzed using chi-squared, ANOVA and Student's t-tests. There was no significant difference found between these two groups in the total number of outliers (8% aCAS versus 9.8% CON, p=0.508). Additionally, there was also no significant difference found for any of the radiographic measurements independently; DFA (8% versus 8%, p=1.00), PTA (4% versus 9%, p=0.184), and PSA (12% versus 12%, p=1.00), when comparing aCAS and CON TKA's. Primary TKAs performed at a single training institution demonstrated no significant difference between aCAS and CON methods in the total number of outliers or in the number of outliers for each postoperative radiographic measurement. This study would suggest that there is no advantage in limiting outliers when utilizing aCAS for TKAs at training institutions in cases that trainees are involved in.

Higher Posterior Tibial Slope and Lower Medial Proximal Tibial Angle of the Knee Are Associated with Delayed Graft Maturation after ACL Reconstruction Surgery with Hamstring Autograft

PurposeThis study aims to relate bone shape with anterior cruciate ligament (ACL) graft maturation, as evaluated by quantitative magnetic resonance imaging (MRI). MethodsWe retrospectively evaluated patients aged 18-60 years who underwent ACL reconstruction with a hamstring autograft with doubled semitendinosus and gracilis at our institution between 2018 and 2020 with isolated ACL injuries. All patients had a minimum follow-up period of 2 years. To evaluate alignment, radiographs of the knee were taken preoperatively. Postoperative 3T magnetic resonance imaging (MRI) and patient-reported outcomes (PRO) scores were acquired at 2 years after surgery. A combined T1ρ/T2 quantification sequence and a 3D multi-echo ultrashort echo-time (UTE) Cones sequence were obtained in a sagittal-oblique plane for better assessment of the ACL graft. After acquiring images, a manual segmentation for ACL graft was performed to assess T1ρ, T2 and UTE T2* relaxation times. Correlations between radiographic parameters or PRO scores and T1ρ, T2 and UTE T2* values were tested with Pearson correlation coefficients. Significance was defined as p<0.05. ResultsSubjects were 28 patients (12 males and 16 females) and had an average age of 34.3 years (SD=8.5 years) and a BMI of 24.4 kg/m2 (SD=4.5 kg/m2). A significant correlation was found between the preoperative PTS and the T1ρ, T2 and UTE T2* relaxation times (r=0.41; p=0.033, r =0.47; p=0.014 and r =0.41; p=0.030), indicating inferior graft maturation in patients with higher PTS. Furthermore, a negative correlation was identified between the preoperative MPTA and the T1ρ, T2 and UTE T2* relaxation times (r=-0.39; p=0.039, r =-0.46; p=0.018 and r =-0.43; p=0.024), indicating inferior graft maturation in patients with greater varus knee alignment. ConclusionThe study findings suggest that an increased PTS and lower MPTA are associated with inferior graft maturation as per T1ρ, T2 and UTE T2* imaging at 2 years post-ACL reconstruction. Level of EvidenceLevel IV retrospective case series

Posterior tibial slope angle in contact versus non-contact anterior cruciate ligament injuries.

Increased Posterior Tibial Slope (PTS) angle has been reported to be a risk factor for primary anterior cruciate ligament (ACL) tears. However, it is unknown whether increased PTS has an associated increased risk for non-contact versus contact ACL injury. The purpose of this study is to determine whether patients with non-contact ACL injury have a higher PTS angle than those with contact ACL injury. A total of 1700 patients who underwent primary ACL reconstruction between January 2011 and June 2023 at a single academic institution were initially included. Electronic medical records were reviewed for demographic information as well as evidence that the patient sustained a contact or non-contact ACL injury. Patients in the contact cohort were propensity score matched to patients in the non-contact cohort by age, sex and BMI. Additionally, patients in the contact cohort were then propensity score matched to a control group of patients with intact ACLs also by age, sex and BMI. One hundred and two patients with contact injury were initially identified and 1598 patients with non-contact injuries were identified. Of the 102, 67 had knee X-rays that were suitable for measurement. These 67 contact injury patients were propensity score matched to 67 noncontact patient and 67 patients with intact ACLs based on age, sex and BMI. There were no significant differences between contact and non-contact cohorts in age (28.7±6.3 vs. 27.1±6.5, p = 0.147), sex (Female: 36.0% vs. 34.3%, p = 0.858), or BMI (26.7±5.6 vs 26.1±3.4, p= 0.475). There was no significant difference in PTS angle between contact versus non-contact ACL injury patients (11.6±3.0 vs.11.6±2.8, p= 0.894). There was a significant difference in PTS between the contact ACL injury and the intact cohort (11.6±3.0 vs. 10.0±3.9, p= 0.010) and the non-contact ACL injury and the intact cohort (11.6±2.8 vs. 10.0±3.9, p = 0.010). There was no significant difference in the degree of PTS between patients who sustained contact versus non-contact ACL injuries. Additionally, there was a significantly increased PTS in both the contact and non-contact ACL injury cohorts compared to patients with intact ACLs.

Long-term surgical outcomes of open reduction and internal fixation (ORIF) in patients with Hoffa-like tibial plateau fractures: a clinical study and analysis.

The Hoffa-like tibial plateau fracture is a rare intra-articular fracture and few studies have investigated its curative effect after treatment. We aimed to focus on patients with Hoffa-like tibial plateau fractures based on a large sample population and to evaluate their long-term surgical outcomes treated with open reduction and internal fixation (ORIF). Between August 2017 and September 2020, a period in which 3256 tibial plateau fractures were treated in five trauma centres. Among them, patients with Hoffa-like tibial plateau fractures who treated with ORIF were retrospectively reviewed. Baseline characteristics, operative information, imaging findings, functional scores and any complications were accurately recorded. Each patient was followed for at least three years. Hoffa-like tibial plateau fractures account for approximately 0.9% (29/3256) of all tibial plateau fractures, including 19 males and ten females with a mean age of 45.8 years. After surgery, all patients obtained anatomical reduction of the fractures and none experienced reduction loss. The final Hospital for Special Surgery score (HSS) was improved compared to one year postoperatively (92.76 ± 3.52 versus 89.03 ± 3.81, P < 0.01). No significant differences (P > 0.05) were found in VAS pain score, Rasmussen score, tibial plateau angle (TPA), and posterior slope angle (PSA) between one year and final follow-up. No serious postoperative complications occurred during the treatment and follow-up. Long-term follow-up results showed that patients with Hoffa-like tibial plateau fractures can achieve stable fracture fixation, low postoperative complications, excellent radiographic findings and good functional recovery with ORIF.

Variation of chin morphology and mandibular incisor length in different facial divergence patterns: New insights from CBCT records.

Evaluate constitutional differences in chin morphology and volume, and mandibular tooth size, between different facial divergence patterns. The sample consisted of 284 pretreatment cone beam computed tomography (CBCT) images of growing and non-growing patients who were stratified into 4 groups based on mandibular plane inclination to cranial base (SN) angle. Linear and angular measurements were made on the lateral CBCT images: mandibular lateral incisor crown (I-C) total (I-A) lengths, the distances between point D (centre of symphysis) and both incisor apex (D-A) and menton (D-Me) and between cemento-enamel junction and menton (CEJ-Me); chin width at the level of the central incisor apex (CWA) and point D (CWD); and the angles of the anterior and posterior symphyseal slopes. The volume of the symphysis was measured using a specialized 3D imaging software. Group differences and associations between parameters were gauged through the three-way ANOVA analysis. I-C, I-A, D-A, D-Me and CEJ-Me were greater in the hyperdivergent group (p < .001). CWA and CWD were wider in the hypodivergent group (p = .003). Volume of the chin and inter-slope angles were similar in all groups (p > .05). The anterior slope angle decreased with hyperdivegence (p < .005) in opposite pattern to the posterior slope angle (p < .005). Shape differences in mandibular symphysis were observed between opposite divergence patterns. Mandibular incisors were longer with hyperdivergence and shorter with hypodivergence. However, chin volumes were similar across divergence groups. These findings underline the role of genetic and environmental factors that impact facial growth.

Steep medial posterior tibial slope angle and ramp lesion are independent risk factors for an increase in quantitatively measured pivot shift in patients with ACL-deficient knees.

Delayed anterior cruciate ligament (ACL) reconstruction often causes residual anterolateral rotatory instability (ALRI) and consequent knee osteoarthritis, warranting the recommendation of early ACL reconstruction within 6 months after injury. Nonetheless, some cases show notable instability, even shortly after injury. The purpose of this study was to identify risk factors for an increase in quantitatively measured pivot shift in patients with ACL-deficient knees within 6 months after injury. Patients with primary ACL reconstruction within 6 months after injury and quantitative triaxial accelerometer measurements of preoperative pivot shift were included. Descriptive statistics were calculated for 11 independent variables (age, gender, time from injury to surgery, KT-1000, knee extension angle, lateral and medial posterior tibial slope angle, medial and lateral meniscus tears, ramp lesion and Tegner active scale). A single regression analysis was performed on the 11 items and acceleration during the pivot shift, and a multiple regression analysis was performed for items with p value less than 0.1. Overall, 111 patients met the inclusion criteria. Single regression analysis showed that medial posterior tibial slope angle, medial meniscus tear and ramp lesion were significantly correlated with acceleration during the pivot shift (p < 0.001, p = 0.04 and p = 0.001). Multiple regression analysis identified medial posterior tibial slope angles and ramp lesions as independent factors for increased preoperative pivot shift (p = 0.005 and 0.01). A steep medial posterior tibial slope angle and ramp lesion were independent risk factors for increased quantitatively measured pivot shift in patients with ACL-deficient knees. Level IV, case series study.

Poster 369: Medial and Lateral Posterior Tibial Slope in the Skeletally Immature: A Cadaveric Study

Objectives: Increased knee posterior tibial slope (PTS) angle is risk factor for primary and secondary ACL injury. Adult biomechanical research indicates that decreasing the PTS may reduce ACL injuries, and osteotomy techniques have been developed to alter tibia slope to reduce risk of re-injury. Pediatric and adolescent athletes have the highest rates of primary and secondary ACL injury, and many in this age group may have abnormal PTS angle. The purpose of this study was to evaluate PTS in medial and lateral tibial plateaus in large database of CT scans, and to develop normative PTS data in this age group. Methods: IRB approval was waived, as the specimens were donated for research, no genetic information was collected, and there were no plans for family contact. 83 pediatric knee CT scans, ranging from ages 1 to 12, were analyzed using OsiriX imaging software. The PTS was evaluated at two distinct points on sagittal CT sections: (1) At the medial tibia plateau and 2) lateral tibial plateau, both aligned with the central part of on a coronal view of the medial femoral and lateral femoral condyles respectively condyle. Results: The average medial PTS angle was 6.56° ± 3.84° and 6.81° ± 3.62° for the lateral PTS. There was not a significant statistical difference between the medial and lateral PTS (P = 0.6632, determined using an independent-samples t-test and analysis of variance). When plotting the age versus PTS, we observed a positive correlation with the medial PTS (R2 = 0.0385) and a negative correlation with the lateral PTS (R2 = 0.0393). Conclusions: The data demonstrate variability in medial and lateral pediatric PTS and provides normative values for pediatric PTS values. For pediatric patients undergoing ACL surgeries, consideration of increased PTS values that are associated with higher rates of recurrent ACL injury may influence surgical treatment techniques. Correction of increased PTS to lower ACL injury risk is performed in adults with major corrective osteotomy surgery, but such procedures have not been performed in children due to osteotomy-induced damage to growth plates. Due to open growth plates, pediatric patients may be treated with minimally invasive guide growth procedures to lower PTS, with minimal complication risk. Guided growth procedures have a long history of successful alignment correction in the coronal plane. Future animal and clinic studies may also demonstrate the safety and effectiveness of guided growth sagittal plane correction as applied to increased PTS. PTS developmental anatomy and its relationship to ACL injury is crucial for surgical advancements, including the use of low risk guided growth interventions to reduce PTS and ACL injury in pediatric patients with high risk of recurrent injury.

Double reverse traction repositor assisted closed reduction and internal fixation versus open reduction and internal fixation for treatment of lateral tibial plateau fractures among the elderly.

In elderly tibial plateau fractures (TPFs), the lateral condyles are involved frequently. This study aimed to compare the outcomes of open reduction and internal fixation (ORIF) and double reverse traction repositor (DRTR) assisted closed reduction and internal fixation (CRIF) in elderly patients with lateral TPFs. From January 2015 to July 2020, we retrospectively reviewed 68 patients treated surgically at our trauma center for lateral TPFs (Schatzker type I-III). 31 patients were eventually assigned to the DRTR assisted CRIF group, whereas 37 patients were assigned to the ORIF group. The primary outcomes included surgical details, radiological assessment, follow-up knee function, and complications. The DRTR assisted CRIF group experienced a 43.6mL decrease in intraoperative blood loss (161.3ml vs 204.9ml, p = 0.033), and the operation duration was 32.1min shorter than the ORIF group (83.8min vs 115.9min, p < 0.001). There was no statistically significant difference in terms of widening of the tibia plateau (WTP), depth of articular depression (DAD), medial proximal tibial angle (MPTA) and posterior tibial slope angle (PTSA) immediately after surgery and at the last follow-up. No differences in malreduction (p = 0.566) or reduction loss (p = 0.623) were observed between the groups, and Lysholm and HSS scores were similar between the two groups (83.6 ± 15.8 vs 83.4 ± 5.1, p = 0.934; 89.3 ± 7.8 vs 86.9 ± 6.2, p = 0.172; respectively). However, ORIF was associated with a greater increase in postoperative complications than DRTR assisted CRIF (3.2% vs 27%, p = 0.008). Both types of internal fixation provide good radiological outcomes and knee function in the treatment of lateral TPFs in the elderly. However, DRTR assisted CRIF has the advantage of a shorter duration of surgery, less blood loss, and fewer postoperative complications, and appears to be a better treatment option for elderly patients with lateral TPFs.

Comparison of Clinical and Radiological Outcomes of Total Knee Arthroplasty in Osteoarthritic Patients.

Background The knee is the joint most commonly affected by osteoarthritis, more than any other. Osteoarthritis is a progressive, long-term condition that leads to the deterioration of joint tissue and cartilage, resulting in pain and impairment. Total knee arthroplasty (TKA) is a successful intervention that improves functional capability, decreases pain, and enhances quality of life. We conducted this study to evaluate whether radiological parameters following TKA influence the clinical outcomes of patients with knee osteoarthritis. Methods The study was conducted on patients treated for knee osteoarthritis at the Department of Orthopedics, Rajindra Hospital and Government Medical College, Patiala, Punjab, in collaboration with the Department of Radiology over a period of 1.5 years. A total of 152 patients diagnosed with knee osteoarthritis were included in the study; all underwent TKA. Patients underwent clinical evaluation and were graded using the Knee Society Score (KSS) during follow-up examinations. Pain was evaluated using the Visual Analog Scale (VAS). Postoperative X-rays were obtained, and various angles, including the distal femoral angle (DFA), the proximal tibial angle (PTA), and the posterior slope angle (PSA), were measured. Patient follow-up was conducted at three days, three months, and six months. Subsequently, a comparison of the clinical and radiological outcomes of TKA was performed. Results In this study, a total of 152 patients participated, with the majority falling into the 61-70 age group. Of these patients, 40.13% were female and 59.87% were male. The average medial DFA was 94.05°, the average medial PTA was 89.31°, and the PSA was 6.6°. Patients with a medial DFA of 94.05° (±3), a medial PTA of 89.31° (±3), and a PSA of 6.6° (±3) were categorized into the normal group. Conclusion Patients with DFA, PTA, and PSA in the normal range demonstrate improved KSS and clinical outcomes.

Subcapital realignment osteotomy for the treatment of moderate and severe slipped upper femoral epiphysis: A retrospective study of 123 hips in a tertiary center.

The surgical treatment of moderate and severe slipped capital femoral epiphysis is controversial. Treatment ranges from pinning in situ to open dislocation and reduction of the slipped epiphysis. The modified Dunn procedure has been associated with variable avascular necrosis with rates, ranging between 0% and 67%. The aim of this study was to evaluate the outcomes and complications of patients who have undergone a subcapital realignment osteotomy (SCRO) in our center. A retrospective longitudinal study of the osteotomies performed between 2009 and 2019 in a tertiary referral center for Pediatric Orthopedics in Queensland, Australia. Patient demographics, stability, and severity of slip and surgical outcomes were collected. A total of 123 procedures were performed on 116 patients. The mean age was 12.4 years, 65 (56%) patients were male and the mean posterior sloping angle was 60.10 with 93 (75%) being severe slips. There were 51 (41.5%) Loder's stable and 72 (58%) unstable slipped capital femoral epiphysis. Our overall avascular necrosis rate following SCRO was 17.8%. Time between surgery and diagnosis did not have an effect on avascular necrosis. The subcapital realignment osteotomy remains a controversial and complex procedure for the management of moderate and severe slipped capital femoral epiphysis. We found that our cohort demonstrated an avascular necrosis rate in keeping with the existing literature. This indicates that when performed in a high-volume center with experienced surgical staff, it can be an effective treatment option for these patients. Level IV.

Evaluation of the efficacy of medial open wedge high tibial osteotomy combined with anterior cruciate ligament reconstruction in the treatment of varus knee osteoarthritis with anterior cruciate ligament injury

Objective: To evaluate the efficacy of medial open wedge high tibial osteotomy (MOWHTO) combined with anterior cruciate ligament (ACL) reconstruction in the treatment of varus knee osteoarthritis (OA) with ACL injury. Methods: A follow-up study. The study retrospectively analyzed the patients underwent MOWHTO combined with ACL reconstruction for treatment of varus knee OA with ACL injury in Tianjin Hospital between April 2018 and September 2022. The preoperative and postoperative posterior slope angle (PSA), hip-knee-ankle angle (HKA), visual analog scale (VAS) pain scores, Lysholm score, International Knee Documentation Committee (IKDC) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, and Tegner score were compared. The follow-up indicators were recorded at 6 weeks, 3 months and 1 year after operation, and the complications were recorded. Results: The study included 32 patients (23 males, 9 females) with a mean age of (50.7±8.4) years. The mean follow-up time was (21.2±4.8) months. PSA increased from 9.2°±1.8° preoperatively to 11.1°±2.4° postoperatively, and HKA increased from 168.7°±2.2° to 181.5°±2.2° (both P<0.01). The indicators such as VAS score (6.8±1.1 vs 1.8±0.4), Lysholm score (52.6±7.1 vs 82.0±6.4), IKDC score (64.7±6.2 vs 80.3±10.0), WOMAC score (51.8±6.3 vs 81.8±6.5), and Tegner score (1.9±0.6 vs 5.0±1.0) were all improved after the operation (all P<0.01). Complications occurred in 5 patients (15.6%), including hematomas, sensory abnormalities, intermuscular vein thrombosis and correction angle loss. Conclusion: MOWHTO combined with ACL reconstruction is a safe and effective approach for the treatment of varus knee OA with ACL injury.

Decreased Posterior Tibial Slope and Its Association With Pediatric Posterior Cruciate Ligament Injury

Background: Recent adult studies have demonstrated that decreased posterior tibial slope angle (PTSA) may be a risk factor for posterior cruciate ligament (PCL) injury. However, there is no study investigating this phenomenon in a pediatric population. Understanding risk factors for PCL injuries among a pediatric population is important given the recent rise in athletic competition/specialization and sports-related injuries. Hypothesis/Purpose: The purpose of this study was to compare PTSA between pediatric patients sustaining a primary PCL tear compared with age- and sex-matched controls. It was hypothesized that pediatric patients sustaining a PCL tear would have a decreased PTSA compared with controls, with decreased PTSA being associated with higher odds of PCL injury. Study Design: Cohort study; Level of evidence, 3. Methods: The records of all patients sustaining a PCL injury between 2006 and 2021 at a level 1 pediatric trauma center were reviewed. Patients aged ≤18 years with magnetic resonance imaging–confirmed PCL tear were included. Excluded were patients with concomitant anterior cruciate ligament tears, previous PCL reconstruction, or previous coronal plane realignment. A control cohort, with their ligament shown as intact on magnetic resonance imaging scans, was matched based on age and sex. PTSA was measured on lateral radiographs of the injured knee or tibia. The mean PTSA was compared between cohorts, and odds ratios were calculated based on the normal slope range (7°-10°) described in the literature, an upper range (>10°), and a lower range (<7°). Inter- and intrarater reliability were determined via calculation of an intraclass correlation coefficient. Results: Of the 98 patients who sustained a PCL injury in this study period, 59 (60%) met inclusion criteria, and 59 healthy knee controls were matched. There were no differences between the cohorts for age (P = .90), sex (P > .99), or body mass index (P = .74). The PCL cohort had a lower mean ± SD PTSA compared with the control group (5.9°± 2.7° vs 7.3°± 4.3°; P = .03). PTSA <7° was associated with a 2.8 (95% CI, 1.3-6.0; P = .01) times risk of PCL tear. Conversely, PTSA >10° was associated with a 0.27 (95% CI, 0.09-0.81; P = .02) times risk of PCL tear. These PTSA measurements demonstrated acceptable intrarater and interrater reliability. Conclusion: PTSA <7° was associated with an increased odds of PCL injury, whereas a slope >10° was associated with a decreased odds of PCL injury in a pediatric population. These findings corroborate similar outcomes in adult studies; however, further studies are needed to elucidate PTSA as a risk factor for PCL injury.

Factors Causing Unintended Sagittal and Axial Alignment Changes in High Tibial Osteotomy: Comparative 3-Dimensional Analysis of Simulation and Actual Surgery

Background: Unintended secondary changes in the posterior tibial slope (PTS) and tibial torsion angle (TTA) may occur after medial open-wedge high tibial osteotomy (MOWHTO). In surgical procedures using patient-specific instruments (PSIs), it is essential to reproduce the PTS and TTA that were planned in simulations. Purpose: To analyze the factors causing unintended sagittal and axial alignment changes after MOWHTO. Study Design: Case series; Level of evidence, 4. Methods: Overall, 63 patients (70 knees) who underwent MOWHTO using a PSI between June 2020 and June 2023 were retrospectively reviewed. Preoperative and postoperative computed tomography scans were 3-dimensionally reconstructed. Simulated osteotomy was performed so that the weightbearing line could pass through the target point. A PSI gapper was 3-dimensionally printed to fit the posteromedial corner of the osteotomy gap in the simulated HTO model. After MOWHTO using the PSI gapper, the actual postoperative model was compared with the preoperative or simulation model. This assessment included PTS, TTA, hinge axis, and osteotomy-related parameters. Cortical breakage around the lateral hinge was evaluated to assess stability. Results: The mean PTS and TTA did not change in the simulation. However, significant changes were observed in the actual postoperative PTS and TTA (change, –2.4°± 2.2° and −3.9°± 4.7°, respectively). The PTS was reduced, while the TTA decreased with internal rotation of the distal fragment. The difference in the axial hinge axis angle (AHA) between the simulation and actual surgery was the factor most correlated with the difference in the PTS (r = 0.625; P < .001). In regression analysis, the difference in the AHA was the only factor associated with the difference in the PTS (β = 0.558; P = .001), and there were no factors that showed any significant associations with the difference in the TTA. In subgroup analyses for the change in the TTA, the correction angle and anterior osteotomy angle were significantly higher in the more internal rotation group (P = .023 and P = .010, respectively). The TTA change was significantly higher in the unstable group with lateral cortical breakage (P = .018). The unstable group was more likely to show an internal rotation of ≥5° (odds ratio, 5.0; P = .007). Conclusion: The AHA was associated with a difference in the PTS between the simulation and actual surgery. The change in the TTA was caused by a combination of multiple factors, such as a large correction angle and anterior osteotomy angle, but mainly by instability of the lateral cortical hinge.

Comparison of short-term radiographic outcomes of medial parapatellar, mini-midvastus, and subvastus surgical approaches in fast-track total knee arthroplasty

Purpose: Due to the difficulties in accessing the knee joint, correct prosthesis placement is of great importance during the implementation of total knee arthroplasty (TKA). This study aimed to compare short-term radiographic X-ray outcomes in patients who underwent fast-track TKA with medial parapatellar (MPP), mini-midvastus (mMV), or subvastus (SV) surgical approaches.&#x0D; Materials and methods: Between 2018 and 2020, 93 patients operated with MPP, mMV, and SV surgical approaches and who had complete data of radiographic outcomes before and sixth-week postoperative were retrospectively analyzed and patients divided into three groups: MPP (n=31), mMV (n=31), and SV (n=31). The alignments of preoperative and sixth-week postoperative X-ray images of the surgical approaches were measured. The operative time of fast-track TKA implementation with MPP, mMV, and SV surgical approaches was recorded.&#x0D; Results: The MPP group had higher preoperative lateral distal femoral angle than the mMV group and a higher preoperative lateral proximal femoral angle than SV group (p=0.018 and p=0.027, respectively). The mMV group had higher postoperative proximal medial tibial angle than SV group (p=0.011). In the postoperative sixth week, the MPP and mMV groups had a lower posterior tibial slope angle than SV group (p=0.001). The MPP approach had significantly shorter operative time than mMV and SV approaches (p=0.001).&#x0D; Conclusion: The outcomes indicate that MPP, mMV, and SV surgical approaches are preferable and feasible in obtaining a satisfactory prosthesis alignment during fast-track TKA. The MPP approach may be preferable because of its shorter operative time and potential advantage in minimizing surgical complication risks.

Changes in Patellar Height and Tibial Posterior Slope after Biplanar High Tibial Osteotomy with Computer-Designed Personalized Surgical Guides: A Retrospective Study.

Medial opening-wedge high tibial osteotomy (MOWHTO) is a surgical procedure to treat medial compartment osteoarthritis in the knee with varus deformity. However, factors such as patellar height (PH) and the sagittal plane's posterior tibial slope angle (PTSA) are potentially overlooked. This study investigated the impact of alignment correction angle guided by computer-designed personalized surgical guide plate (PSGP) in MOWHTO on PH and PTSA, offering insights for enhancing surgical techniques. This retrospective study included patients who underwent 3D-printed PSGP-assisted MOWHTO at our institution from March to September 2022. The paired t-tests assessed differences in all preoperative and postoperative measurement parameters. Multivariate linear regression analysis examined correlations between PTSA, CDI (Caton-Deschamps Index), and the alignment correction magnitude. Receiver operating characteristic (ROC) curve analysis determined the threshold of the correction angle, calculating sensitivity, specificity, and area under the curve. A total of 107 patients were included in our study. The CDI changed from a preoperative mean of 0.97 ± 0.13 (range 0.70-1.34) to a postoperative mean of 0.82 ± 0.13 (range 0.55-1.20). PTSA changed from a preoperative mean of 8.54 ± 2.67 (range 2.19-17.55) to a postoperative mean of 10.54 ± 3.05 (range 4.48-18.05). The t-test revealed statistically significant changes in both values (p < 0.05). A significant alteration in patellar height occurred when the correction angle exceeded 9.39°. Moreover, this paper illustrates a negative correlation between CDI change and the correction angle and preoperative PTSA. Holding other factors constant, each 1-degree increase in the correction angle led to a 0.017 decrease in postoperative CDI, and each 1-degree increase in preoperative PTSA resulted in a 0.008 decrease in postoperative CDI. PTSA change was positively correlated only with the correction angle; for each 1-degree increase in the opening angle, postoperative PTS increased by 0.188, with other factors constant. This study highlights the effectiveness and precision of PSGP-assisted MOWHTO, focusing on the impact of alignment correction on PH and PTSA. These findings support the optimization of PSGP technology, which offers simpler, faster, and safer surgeries with less radiation and bleeding than traditional methods. However, PSGP's one-time use design and the learning curve required for its application are limitations, suggesting areas for further research.

Risk factors of failure results after double-bundle reconstruction with autogenous hamstring grafts for isolated posterior cruciate ligament rupture cases

Posterior tibial translation (PTT) after double-bundle posterior cruciate ligament (PCL) reconstruction has sometimes occurred. Purpose of this study is to identify the risk factors for postoperative PTT after double-bundle PCL reconstruction with a hamstring autograft. Comparing the results of bilateral gravity sag view (GSV) at 12 months after surgery, over 5-mm PTT was defined as ‘failure’ in this study. Of 26 isolated PCL reconstruction cases, over 5-mm PTT was seen in 7 cases (group F: 9.57 ± 1.28 mm), and 19 cases had less than 5 mm (group G: 2.84 ± 1.29 mm). Age, sex, body mass index (BMI), preoperative GSV, posterior slope angle of the tibia, anterolateral bundle (ALB) and posteromedial bundle (PMB) graft diameters, and tibial tunnel diameter were evaluated. The two groups were compared with the 2 × 2 chi-squared test, the Mann Whitney U-test, and Spearman’s rank correlation coefficient. Multivariate logistic regression analysis was also performed to determine the risk factor. Statistical significance was indicated as p < 0.01 for correlation with postoperative PTT, and as p < 0.05 for all other comparisons. Mean age (group G 31.8 ± 12.5 vs group F 34.9 ± 15.9 years), sex (male/female: 15/4 vs 3/4), BMI (25.6 ± 4.6 vs 24.9 ± 3.9 kg/m2), preoperative GSV (11.3 ± 2.2 vs 11.6 ± 2.9 mm), PMB diameter (5.37 ± 0.33 vs 5.36 ± 0.48 mm), and tibial tunnel diameter (9.32 ± 0.58 vs 9.29 ± 0.49 mm) showed no significant differences. ALB diameter was significantly greater in group G (7.0 ± 0.5 mm) than in group F (6.5 ± 0.29 mm; p = 0.022). There was also a significant difference in posterior tibial slope angle (group G 9.19 ± 1.94 vs group F 6.54 ± 1.45, p = 0.004). On Spearman rank correlation coefficient analysis, ALB diameter GSV (correlation coefficient: − 0.561, p = 0.003) and posterior tibial slope angle (correlation coefficient: − 0.533, p = 0.005) showed a significant correlation with postoperative PTT. Multivariate logistic regression analysis showed that ALB diameter (OR 19.028; 95% CI 1.082–334.6; p = 0.044) and posterior slope angle of tibia (OR 3.081; 95% CI 1.109–8.556; p = 0.031) were independently associated with postoperative PTT, respectively. In double-bundle PCL reconstruction with hamstring, smaller ALB graft diameter and lower (flatted) tibial slope angle were considered risk factors for postoperative PTT.

Risk of tibial baseplate loosening is low in patients following unrestricted kinematic alignment total knee arthroplasty using a cruciate-retaining medial conforming insert: A study using radiostereometric analysisat 2 years.

Assessing the risk of tibial baseplate loosening in patients after unrestricted kinematically aligned (unKA) total knee arthroplasty (TKA) using a medially conforming insert is important because baseplates generally are aligned in varus which has been linked to an increased incidence of aseptic loosening following mechanically aligned TKA. Two limits that indicate long-term stability in patients are a change in maximum total point motion between 1 and 2 years (ΔMTPM) < 0.2 mm and anterior tilt at 2 years < 0.8°. The purposes were to determine: (1) the number of patients with ΔMTPM > 0.2 mm, (2) the number of patients with anterior tilt > 0.8°and (3) whether increased varus baseplate and limb alignment were associated with increased migration. Thirty-five patients underwent cemented, caliper-verified, unKA TKA using a medially conforming tibial insert with posterior cruciate ligament (PCL) retention. Biplanar radiographs acquired on the day of surgery and at 1.5, 3, 6, 12and 24 months were processed with model-based radiostereometric analysis (RSA) software to determine migration and the number of patients with migration above the two stability limits. Medial proximal tibial angle (MPTA), hip-knee-ankle angle (HKAA)and posterior slope angle (PSA) were analyzed for an association with migration in six degrees of freedom and in MTPM. Thirty-two of 35 patients were available for analysis at 2 years. One patient exhibited ΔMTPM > 0.2 mm. The same patient exhibited anterior tilt > 0.8°. Varus rotation (p = 0.048, r ≤ 0.34) and medial translation (p = 0.0273, r ≤ 0.29) increased with increased varus baseplate alignment. The results indicate low risk of long-term baseplate loosening in patients. Although varus rotation and medial translation increased with increased varus baseplate alignment, the magnitudes of the migrations were minimal and did not increase ΔMTPM and anterior tilt. Level II, therapeutic prospective cohort study.

Change in Posterior Tibial Slope Angle After Displaced Pediatric Tibial Tubercle Fracture: A Model for Growth Modulation in the ACL-Deficient Knee.

Increased posterior tibial slope angle (PTSA) has been shown to be an important risk factor for anterior cruciate ligament (ACL) injury. PTSA modulation is not utilized routinely to reduce risk of primary rupture or graft failure. Displaced tibial tubercle (TT) fractures in the skeletally immature are associated with potential growth arrest and may be used as a model to study PTSA changes in this setting. To quantify the change in PTSA (ΔPTSA) after operative treatment of displaced TT fractures in skeletally immature patients. It was hypothesized that there would be a progressive decrease in PTSA after TT injury and that rate of ΔPTSA would be highest during peak growth velocity. Case series; Level of evidence, 4. Included were 22 patients (n = 23 knees; mean chronological and bone age at injury, 14 years; 86% male) who underwent surgery for displaced TT fracture. PTSA was measured on lateral radiographs at time of surgery and subsequent follow-up, and bone age at the time of injury was determined using radiographic standards. The rate of ΔPTSA for individual patient, total cohort, and sex-based subgroup trends were determined via linear regression (degrees per month; positive value indicates relatively anterior). Individual patient regression coefficients were averaged into bone age cohorts. Average follow-up was 17 months (range, 6-52 months). The mean PTSA was -12°± 2.4° at the time of injury, and the mean ΔPTSA for the cohort was 0.30°± 0.31° per month (range, -0.27° to 0.97° per month). Linear regression demonstrated a significant relationship between months postfixation and PTSA, demonstrating a ΔPTSA of 0.31° per month (95% confidence interval [CI], 0.24° to 0.38°; P < .001). The highest ΔPTSA was seen at bone age 14 years (mean, 0.58°± 0.44° per month). The mean absolute change in PTSA from injury to final follow-up was 4.1° (range, -3.4° to 21°). Our data suggested that PTSA becomes more anterior after operatively treated pediatric TT fractures and that ΔPTSA may be influenced by bone age. This concept may be useful in considering surgical modulation of excessive PTSA in the pediatric ACL-deficient knee.

Mid-term effects of unicompartmental knee arthroplasty combined with anterior cruciate ligament reconstruction for the medial compartment osteoarthritis with anterior cruciate ligament deficiency by proportioning with the pure medial compartment osteoarthritis

Objective: To evaluate the mid-term efficacy of one-stage unicompartmental knee arthroplasty (UKA) combined with anterior cruciate ligament (ACL) reconstruction in the treatment of medial compartment osteoarthritis (OA) with ACL deficiency. Methods: Retrospective cohort study. The clinical data of 13 patients (14 knees) who underwent UKA with ACL reconstruction for knee medial compartment OA combined with ACL deficiency in Wangjing Hospital of China Academy of Chinese Medical Sciences from January 2012 to January 2020 were retrospective analyzed. A 1∶1 proportioning study was conducted with 13 patients (14 knees) who underwent UKA due to medial compartment OA with intact ACL during the same period. The matching conditions were the same gender, age, surgical side, anesthesia method, comorbidities, and imaging lesions. There were 26 patients (28 knees) in the two groups, including 6 males (6 knees) and 20 females (22 knees), aged (58.9±4.2) years. The range of motion (ROM) and Oxford Knee Score (OKS) were used to evaluate the knee joint function at the last follow-up. The anteroposterior, lateral and axial X-ray films of the knee joint and the weight-bearing full-length X-ray films of the lower limbs were taken during follow-up. The hip knee ankle (HKA) angle, the posterior slope angle (PSA) of tibial prosthesis, and the anterior tibial translation (ATT) were recorded and compared between the two groups. The progression of lateral compartment OA, prosthesis loosening, and dislocation were evaluated. The mid-term follow-up clinical efficacy of the two surgical methods was compared, and the etiology of the patients was analyzed to verify the clinical efficacy and patient selection of one-stage UKA combined with ACL reconstruction. Results: The follow-up time of the two groups was (7.14±2.45) years. At the last follow-up, there was no significant difference in joint ROM between the combined group and the UKA group (120.90°±2.95° vs 122.29°±3.22°, P=0.260). There was no significant difference in OKS score between the two groups [(42.50±1.99) vs (43.21±2.26), P=0.380]. There was no significant difference in HKA angle and ATT distance between the two groups before operation (both P>0.05). At the last follow-up, the results were better than those before operation, and the differences were statistically significant (both P<0.05). At the last follow-up, there was no significant difference in HKA Angle between the combined group and the simple group (177.79°±1.25 ° vs 177.86°±1.29°, P=0.880). Tibial prosthesis PSA and ATT distance were not significantly different between the two groups [(4.57°±0.94° vs 4.50°±1.34°and (0.21±0.89) mm vs (0.14±1.35) mm, both P>0.05)]. There was no prosthesis loosening and obvious progression of lateral compartment OA in both groups at the last follow-up. Conclusion: For young patients with medial compartment OA secondary to ACL deficiency, UKA combined with ACL reconstruction is recommended, it can obtain good mid-term results.

Evaluation of the relationship of posterior tibial slope with gender and age in Turkish population with 3 different methods

BackgroundThis study aimed to reveal the posterior tibial slope (PTS) angle with 3 different methods in a large case group in the Turkish population. In addition, the reproducibility of the measurement methods used was questioned while determining the age groups, gender and side relationship of this angle.Materials and methodsIn our retrospective study, radiographs of both knees were evaluated in all 610 patients (344 women, 56.4%) aged 25–65 years. PTS angles were measured by a radiologist and an orthopedist using anterior tibial cortex (ATC), posterior tibial cortex (PTC) and proximal tibial anatomical axis (PTAA) methods. The relationship of these angles with age group and gender, and the intra-class and inter-class correlations of all three methods were evaluated.ResultsThe mean and standard deviation (SD) of PTS angle was 11.03 ± 2.33° with ATC method, 6.25 ± 2.22° with PTC and 8.68 ± 2.16° with PTAA, and the difference was significant (p < .001). In the evaluation according to age groups, the highest mean PTS angles were detected in cases aged 25–35 (9.63 ± 1.97° [mean ± SD] by PTAA method), and there was a significant difference in comparison with other age groups (p < .05). In comparison with age groups, higher mean PTS angles were found in women and on the right side, but the difference was not statistically significant (p > .05). The intraclass and interclass correlation coefficient (ICC) of all three methods was excellent (ICC > 0.91).ConclusionThis study emphasizes that the mean PTS angle in Turkish population is higher than the angle values ​​recommended by prosthesis manufacturers, and factors such as patient age and gender should be calculated in order to ensure more effective prostheses to be applied to patients.