Tibial Fixation Research Articles

Effect of Fibula Shortening on Medial Clear Space and Lateral Translation of the Talus: An Anatomical Cadaveric Study

Category: Ankle; Trauma Introduction/Purpose: Fibular shortening with an medial and syndesmotic ligament instability causes lateral translation of the talus. We hypothesise that the interaction of the anterior inferior tibiofibular ligament (AITFL) tubercle of the fibular with the anterior tibial incisura would precipitate lateral translation due to the size differential. Methods: Twelve cadaveric ankle specimens were dissected, removing all soft tissue except for ligaments. They were fixed onto a bespoke jig allowing tibial fixation and free movement of the talus and fibula. The fibula was progressively shortened in 5mm increments until complete ankle dislocation, measuring the medial clear space with each increment. Results: The larger AITFL tubercle interaction with the smaller tibial incisura caused a significant increase in lateral translation of the talus. This occurred in most ankles between 5-10mm of fibular shortening. The medial clear space widened following 5mm of shortening in 5 specimens (mean: 2.07, s.d: 2.53). All 12 specimens experienced widening by 10mm fibular shortening (Mean: 7.21mm, s.d: 2.21) and reached complete dislocation by 35mm fibular shortening. Conclusion: This study shows, that with fibular shortening, the interaction between the distal fibular AITFL tubercle and the anterior tibial incisura precipitates a lateral translation of the talus in an ankle fracture model where the medial and syndesmotic ligaments have been transected and the lateral ligaments remain intact. The interaction occurred between 5 and 10mm of fibular shortening. Beyond this point there was a near linear correlation between fibular shortening and medial clear space widening

Dependence of Total Ankle Tibial Baseplate Stability Upon Bone Density

Category: Ankle Arthritis Introduction/Purpose: The success of total ankle replacement (TAR) in improving patient outcomes is linked to its initial stability after implantation. Limiting early micromotion between implant and bone improves longer-term stability. Tibial component design fixation features play a critical role in determining early stability, with retention of medial and lateral bone sidewalls and interference press-fit both used to supplement fixation. However, tibial component stability is likely also influenced by regional bone density characteristics, and the exact relationship between the two is not adequately understood. The goal of this study was to investigate how bone density affects tibial component stability and bone-implant interface micromotion between the tibial component of a specific TAR and the distal tibia, by using finite element analysis (FEA) during simulated gait. Methods: A commercially available TAR tibial component baseplate was virtually inserted into a computer model of the distal tibia from two patients with end-stage ankle arthritis. These patients were selected based on having different bone density profiles in the affected ankle. The tibia models were generated from patient CT scans, having a CT density-based inhomogeneous material distribution (Fig. 1a) that allowed for bone compaction after press-fit. The tibial component was modeled as titanium alloy material. Two different fixation cases were simulated using FEA: (1) retained medial/lateral sidewalls + line-to-line fit, and (2) retained sidewalls + 50µm interference press-fit. FEA was performed using body weight-scaled kinetic (forces/moments) profiles representing the stance phase of gait, applied to the distal implant surface, while the proximal tibia was held fixed. Press-fit was simulated prior to gait simulation (interference press-fit cases). Micromotions were defined as displacement differences between bone-implant closest nodal pairs, computed from FEA output. Results: For the case with sidewalls+line-to-line fit, micromotions were largest early and late in the stance phase of gait (Fig. 1b), with the largest micromotions observed at heel strike (0% stance). Dorsiflexion and inversion moments dominate in early stance, stressing the anterior edge of the tibia in contact with the implant, leading to relatively large posterior/lateral gapping (Fig. 1b, inset). The observed differences in micromotion between the two patients correlated with differences in bone quality at the tibia contact surface, particularly around the implant pegs (Fig. 1a). However, when interference press-fit was modeled, the differences in micromotion between the two subjects largely disappeared (Fig. 1c), as adequate bone compaction was generated around the interference regions with sufficient bone quality to resist micromotion (Fig. 1d). Conclusion: This study presents novel insight into the effect of TAR fixation features and the associated micromotion at the bone- implant interface in patients with varying distal tibia bone density. We found the stability of the tibial implant to be considerably affected by surrounding bone quality, but the influence of bone quality on implant stability was minimized when interference press- fit was introduced. While a more comprehensive understanding of TAR implant features and their performance is needed, we believe the results of this study clearly demonstrate the importance of bone quality and particularly implant interference press-fit in the stability of TAR implants.

Dependence of Total Ankle Tibial Baseplate Stability Upon Device Fixation Features

Category: Ankle Arthritis Introduction/Purpose: Patient outcomes and construct longevity after total ankle replacement (TAR) are both linked to initial implant stability. Limited early micromotion between the implant and bone encourages stability. Tibial component design fixation features play a critical role in determining the initial stability, with retention of medial and lateral bone sidewalls and interference press-fit used to supplement fixation. The goal of this study was to characterize micromotion between the tibia and baseplate using finite element analysis (FEA) to determine how baseplate design features influence stability. Methods: Three commercially available TAR tibial component baseplate designs were virtually inserted into a computer model of the distal tibia of an end-stage ankle arthritis patient (Fig. 1a). Implant insertion was simulated using FEA for each tibial component with two different fixation cases: (1) no sidewalls+line-to-line fit and (2) sidewalls retained+50µm interference press-fit. Tibia models were derived from patient CT scans, with element-by-element material properties assigned based upon CT Hounsfield units. The tibial components were assigned titanium alloy properties. Following simulated implantation, FEA was performed using kinematic and kinetic profiles representing the stance phase of gait. Loads/moments scaled to patient body weight were applied to the implant (Fig. 1b, 1c), while the proximal tibia was held fixed. Micromotions were defined as the displacement difference between bone-implant closest nodal pairs, computed from FEA output using custom-written code. Results: Amongst tibial component designs inserted without sidewalls and with line-to-line fit, relatively large micromotions were observed. Micromotion differences at heel strike between Peg Designs 1 and 2 may be attributable to sidewall height, while Peg Design 3 was less susceptible to the proximal forces and dorsiflexion moments dominant in early stance (Fig. 1d), potentially because of its angled anterior pegs. Micromotions in Peg Design 3 were largest near toe off, where the plantarflexion moment and decreased proximal force may have permitted motion along the pegs. Differences in micromotion between the different implant designs over the stance phase of gait were greatly reduced when interference press-fit was modeled (Fig. 1e). Conclusion: This study provides new insight on the relative initial stability afforded by different TAR fixation features across designs. In the absence of interference press-fit, all designs showed micromotions large enough to be concerning. However, when interference press-fit was modeled, all designs performed similarly in terms of initial stability during simulated gait. While a better understanding of the relationships between TAR implant features, patient bone density profiles, and initial stability is still needed, our findings suggest that implant interference press-fit plays an important and dominant role in device performance.

Early-to-Intermediate Clinical and Radiographic Outcomes of the Vantage Total Ankle Arthroplasty

Category: Ankle Arthritis Introduction/Purpose: The Vantage total ankle arthroplasty (TAA) features a design based on careful study of arthritic ankles and current ankle biomechanics, with theoretical advantages of a vertically-oriented tibial fixation and a fully congruent talar dome bone-implant interface. In this design-team, single-institution investigation, we report early-to-intermediate term clinical and radiographic outcomes, implant survivorship, and complications of the Vantage TAA. Methods: We retrospectively reviewed prospectively collected data for 278 consecutive patients undergoing Vantage fixed-bearing TAA. Ankles with coronal plane deformity > 25 degrees and suspected poor bone quality were prospectively excluded. Prospectively collected data includes: PROMIS, SF-36, SMFA, VAS and AOFAS hindfoot-ankle scores. Using previously published and commonly accepted evaluation methods, independent radiographic analysis, performed by a non-design surgeon investigator, included pre-operative, 1-year, and most recent follow-up assessments of 2-plane alignment, component position, and the bone- implant interface. A non-design surgeon investigator with dedicated training in statistics performed the statistical analysis using descriptive statistics to report PROM and radiographic measures and Kaplan-Meier survivorship analysis. Results: Mean patient age was 64.8yrs (range:33-86), 44.2% were female, and mean follow-up was 3.1yrs (2.0-5.5). Mean preoperative and postoperative PROMs were as following: PROMIS-Depression 50.3+/-4.2 and 45.6+/-9.8, PROMIS-Physical Function 39.0+/-3.4 and 45.0+/-7.8, SF-36 total score 55.8+/-15.3 and 73.2+/-20.0, SMFA-Function 29.0+/-13.5 and 15.9+/-5.4, VAS 15.8+/-24.8 and 3.1+/-10.1, and AOFAS hindfoot-ankle 46.3+/-16.5 and 81.1+/-16.3 (Table 1). Radiographic lucency at the bone- implant interface was noted in 33 (18.5%) TAAs at final follow-up; 20 (11.2%) were progressive. Lucency was almost exclusive to the tibial component. Implant survivorship was 99.6% [98.9-100.0] at 1-year and 93.3% [88.7-98.2] at the 5-year mark (Table 2, Figure 1). We identified suboptimal bone preparation, initial component alignment and/or component position in all 11 implant failures (Table 3). Conclusion: At early-to-intermediate followup, we observed favorable clinical outcomes, radiographic results and implant survivorship for the fixed-bearing Vantage TAA, especially with optimal bone preparation and component position. Tibial component lucency remains a concern and warrants further investigation. Suboptimal bone preparation, initial component alignment and/or component position was observed in all implant failures.

DISTAL THIRD TIBIAL FRACTURE SURGERY WITH FIBULAR FIXATION: IS IT NECESSARY FOR UNION AND ALIGNMENT?

Objective
 The management of distal third tibial fractures remain
 controversial. The aim of the present study was to
 evaluate whether concurrent fibular fixation changes
 union rates and aids in alignment in the case of distal
 third tibia fractures.
 Material and Method
 The study included 106 distal third tibia fracture
 operation cases in which the distance from the fracture
 to the plafond was between 3-12 cm at a single centre
 between January 2016 and June 2020. The patients
 were divided into three groups according to the status
 of the fibula: Group 1 (without fibular fixation with
 the presence of a fibula fracture, 47 cases), Group
 2 (concurrent fibular fixation with the presence of a
 fibular fracture, 38 cases) and Group 3 (intact fibula,
 21 cases). All fibular fixation surgeries were performed
 with locked plates (LCP) and tibial fixation with either
 LCP or intramedullary nailing (IMN). The primary
 outcome measures were union and alignment. Age,
 gender, AO classification, fibula fracture location,
 presence of an open fracture, implant type and time
 delay for surgery were also assessed.
 Results
 None of the variables except the presence of an open
 fracture was significant for the union rates or alignment.
 The union rate was significantly less if there was an
 open fracture in the concurrent fibular fixation group
 (p

Influence of Posterior Tibial Slope on the Risk of Recurrence After Anterior Cruciate Ligament Reconstruction

Background. Anterior cruciate ligament (ACL) graft rupture has multifactorial causes, with traumatic factors being the most prevalent. Modern literature presents conflicting data regarding the influence of the posterior tibial slope on the risk of traumatic ACL graft rupture.
 Aim of the study to determine if there is a correlation between the posterior tibial slope and ACL graft injury in patients who have previously undergone ACL reconstruction.
 Methods. This was a single-center cohort retrospective study that included patients diagnosed with a complete ACL rupture and who had undergone ACL reconstruction using standard techniques without graft rupture at the last follow-up. Inclusion criteria for the first group included a diagnosis of traumatic ACL rupture followed by reconstruction, a graft composed of semitendinosus and gracilis tendons (St+Gr), femoral fixation with a cortical button, tibial fixation with a sleeve and screw, and the absence of graft rupture at the time of the study. This group included 30 consecutive patients (15 males and 15 females) with a mean age of 36.3 years (min 17, max 59). Inclusion criteria for the second group included an indirect traumatic mechanism of ACL graft rupture and subsequent revision ACL reconstruction. This group consisted of 33 patients (23 males and 10 females) with a mean age of 33.0 years (min 19, max 60). The lateral (LPTS) and medial (MPTS) posterior tibial slopes were measured on lateral knee radiographs.
 Results. The median time from surgery to the last follow-up in the first group was 65 months (IQR 60; 66), while in the second group, it was 48 months (IQR 9; 84). The median MPTS in the first group was 7.8 (IQR 5.3; 9.4), while in the second group, it was 8.5 (IQR 7.5; 11). The median LPTS in the first group was 9.9 (IQR 8.4; 12.1), whereas in the second group, it was 12.0 (IQR 9; 15.4). There was no statistically significant difference in MPTS and LPTS based on gender in both groups and the entire sample (p0.05). When comparing LPTS values between both groups, a statistically significant difference (p = 0.04) was found, with higher LPTS values in patients in the second group (with ACL graft injury).
 Conclusion. Increased posterior tibial slope, particularly LPTS, is identified as a potential predictor of ACL graft rupture. The study demonstrates the impact of LPTS on the risk of ACL graft rupture (p0.05) in cases of indirect traumatic injury.

747 Ten Year Outcomes After Surgical Fixation of Tibial Plateau Fractures

Abstract Aim This study represents one of the largest clinical case series' evaluating long-term outcomes following surgical fixation of tibial plateau fractures over a 10-year follow-up. The primary aim is to evaluate the incidence of TKR and risk-factors associated with poor outcomes. Method Patients receiving surgical fixation of tibial plateau fractures between 2008 – 2012 were included. Those requiring arthroplasty or endoprosthesis post-injury were excluded. PACs was used to analyse case notes and radiographic imaging. Articular reduction and alignment (mPTA) were measured using pre-operative radiographs. Comparisons were made with radiographs post-fracture union (6-weeks to 6-months), assessing fracture reduction maintenance. Long-term outcomes were assessed for patients receiving imaging thereafter. Patients were checked using the Scottish National Imaging Archive. Results 130 patients presented various fractures (Schatzker I-III n = 78, IV n = 12, V n = 9, VI n = 29) and 2 open-fractures. 32 patients required further surgery, 13 required multiple operations - resulting in 47 operations. These included metalwork removal (n = 28, 21.5%), TKR (n = 12, 9.2%), washout for infection (n = 3, 2.3%), osteotomy (n = 2, 1.5%), sequestrectomy (n = 1, 0.8%), and above knee amputation (n = 1, 0.8%). ≥ 2mm articular reduction was maintained in the majority (84%); however, good articular reduction did not prevent progression to arthroplasty (average step 1.4mm in TKR versus 1.8mm in non-TKR). Good alignment correlated with favourable outcomes - average mPTA being 90.8° in non-TKR versus 93.5° in TKR. Conclusions These findings support previous literature in this field demonstrating that malalignment, rather than articular depression, increases the risk for post-traumatic arthritis requiring arthroplasty. The incidence of TKR after tibial plateau fracture fixation at 10-years was 9.2%.

Stemmed Tibial Fixation for Primary Total Knee Arthroplasty in Obese Patients—A National Registry Study

BackgroundWe investigated if the use of augmented tibial fixation with stems in primary total knee arthroplasty (TKA) in obese patients was associated with a difference in reason for revision, type of revision, or overall revision rate. MethodsData from the Australian Orthopaedic Association National Joint Replacement Registry compared reason for revision, rate, and type of revision between primary TKA using stemmed tibial prostheses to nonstemmed prostheses, stratified by body mass index (BMI) and obesity. The cumulative percent revision was obtained using the Kaplan-Meier method, and Cox proportional hazards models estimated hazard ratios (HRs) adjusted for age and sex with 95% confidence intervals (CIs). All tests were 2-tailed at 5% statistical significance (P < .05). There were 66,508 procedures available for analyses. ResultsObese class 2 (BMI 35 to 39.99) had higher rates of revision in the stemmed group compared to the nonstemmed group (HR 1.44, 95% CI 1.00, 2.05, P = .047). There was no significant difference in revision rates between stemmed and nonstemmed tibial prostheses in any other BMI group. Primary TKA in obese patients (BMI ≥30) with a stem extension had a significantly higher rate of minor revisions compared to no stem extension (HR 1.31, 95% CI 1.03, 1.66, P = .025). There was no significant difference between stemmed and nonstemmed groups for major revision in obese patients and for minor or major revision in nonobese patients. ConclusionUsing a tibial stem during primary TKA in obese patients is not associated with a lower rate of revision.

Determination of Posterior Tibial Slope Changes After Tibial Plateau Fracture Fixation: A Retrospective Case Series.

A tibial plateau fracture is an intra-articular fracture that affects the function and stability of the knee joint and requires careful evaluation and pre-operative planning. We determined the posterior tibial slope changes after tibial plateau fracture stabilization, aiming to help improve surgical success in maintaining the lower limb's natural axis. This retrospective case series involved all Golestan and Imam Khomeini hospital patients (Ahvaz, Iran) with Schatzker type IV-VI tibial plateau fractures from April 1, 2017, to March 30, 2020, who underwent surgical fixation. Data on the age, gender, body mass index (BMI), surgical approach, posterior tibial slope angle in the injured and healthy knees, pain, and knee joint instability were collected. We analyzed the data using SPSS version 22 and considered a significance level of P < 0.05. Among the 31 study participants, 24 (77.4%) were males. The mean age of the patients was 39.81 ± 14.41 years (21-78), with a mean BMI of 25.4 ± 2.7 (20.3-31.2) kg/m2 and hospitalization duration of 5.8 ± 9.3 days (3-29). Most patients had type VI fractures (48.3%). The posterior tibial slope angle shared no relation with age, gender, BMI, or surgical approach (P > 0.05). After tibial plateau fracture fixation, the posterior tibial slope angle significantly increased in the injured knee compared with the healthy knee (P < 0.05). Six months after the operation, the angle of the injured knee decreased but remained higher than that of the healthy knee (P > 0.05). The tibial slope's posterior column collapses more than its anterior column over time, reducing the posterior tibial slope angle. Therefore, the correct reduction of the tibial plateau's posterior slope is more important.

Circular external fixation for revision of failed tibia internal fixation.

The management of failed tibial fracture fixation remains a challenge for orthopaedic surgeons. This study investigate the utility and outcomes of circular external fixation in the management of failed internal fixation of tibial fractures. Retrospective review of a prospectively collected database of a complex limb reconstruction unit at a major trauma centre was done during December 2022. Patients with failed internal fixation of tibial fracture who underwent revision surgery with circular external fixation frame were included. 20 patients with a mean age of 47.8 ± 16.5years (range: 15-69) were included. Fourteen (70.0%) patients had failed plate and screws fixations, and the remaining six (30.0%) failed intramedullary nail fixation. The most common indication for revision surgery was development of early postoperative surgical site infection (5 patients; 25.0%). The mean duration of frame treatment was 199.5 ± 80.1days (range = 49-364), while the mean follow-up duration following frame removal was 3.2 ± 1.8years (range = 2-8). The overall union rate in this series was 100%; and all infected cases had complete resolution from infection. The total number of complications was 11, however, only two complications required surgical intervention. The most common complications reported were pin site infection (6; 30.0%) and limb length discrepancy of 2cm (2; 10.0%). Circular external fixation is a reliable surgical option in the treatment of failed internal fixation of tibia fractures. This technique can provide limb salvage in complex infected and noninfected cases with a high union rate and minimal major complications.

Risk of Neurovascular Injury during Screw Fixation of Tibial Tubercle Fractures in Pediatric and Adolescent Patients.

Objective To review knee magnetic resonance imaging (MRI) scans for the analysis of the location of neurovascular structures (NVSs), and to define the risk of bicortical fixation. Methods Distances between the posterior cortex and the popliteal NVSs were measured on the MRI scans of 45 adolescents (50 knees) at 3 levels (C1: center of the proximal tibial epiphysis; C2: 10 mm distal to the physis; and C3: 20 mm distal to the physis). The NVSs located between 5 mm and 10 mm from the incision were considered in a zone of moderate risk for damage, while those less than 5 mm from the incision were considered in a zone of high risk for damage, and those more than 10 mm from the incision were considered to be in a zone of low risk for damage. The independent Student t -test was used for the comparison of the NVS distance 0with gender, skeletal maturity, and the tibial tubercle-trochlear groove (TT-TG) distance. Values of p < 0.05 were regarded as statistically significant. Results The path of the C1 screw posed an increased risk of damage to the popliteal artery and vein compared with other screw paths ( p < 0.001). The popliteal artery has a high risk of damage at the level of C1 (4.2 ± 2.2mm), and a moderate risk at C2 (9.6 ± 2.4mm), and the popliteal vein has a moderate risk at C1 (6.0 ± 2.7 mm), and a low risk at C2 and C3 (10.8 ± 3.1mm, and 12.05 ± 3.1mm respectively). The C3 position presented the lowest risk of damage to these structures ( p < 0.001). The distance between the posterior tibial cortex and the posterior tibial nerve was < 15 mm at the 3 levels analyzed (C1: 11.0 ± 3.7 mm; C2: 13.1 ± 3.8 mm; and C3: 13 ± 3.9 mm). Conclusions The present study clarifies that the popliteal vessels are at risk of injury during tibial tubercle screw fixation, particularly when drilling the proximal tibial epiphysis. Monocortical drilling and screw fixation are recommended for the surgical treatment of tibial tubercle fractures. Level of Evidence III Diagnostic study.

A multimodal assessment of cementless tibial baseplate fixation using radiography, radiostereometric analysis, and magnetic resonance imaging.

Fixation in cementless total knee arthroplasty is provided by osseous integration. Radiography, radiostereometric analysis (RSA), and magnetic resonance imaging (MRI) were used simultaneously to investigate fixation. Relationships between RSA-measured implant micromotions and MRI-evaluated osseous integration at the component-bone interface were assessed in 10 patients up to 6 months postoperation. Supine MRI (using multispectral imaging sequences) and RSA exams were performed to evaluate osseous integration and measure longitudinal migration, respectively. Inducible displacement was measured from standing RSA exams. Radiolucent lines were detected on conventional radiographs. Of 10 patients, 6 had fibrous membranes detected on MRI. No fluid or osteolytic interfaces were found, and no components were scored loose. Of 10 patients, 6 had radiolucent lines detected. Average maximum total point motion (MTPM) for longitudinal migration at 6 months was 0.816 mm (range 0.344-1.462 mm). Average MTPM for inducible displacement at 6 months was 1.083 mm (range 0.553-1.780 mm). Fictive points located in fibrous-classified baseplate quadrants had greater longitudinal migration than fictive points located in baseplate quadrants with normal interfaces at 2 weeks (p = 0.031), 6 weeks (p = 0.046), and 3 months (p = 0.047), and greater inducible displacements at 3 months (p = 0.011) and 6 months (p = 0.045). Greater early micromotion may be associated with the presence of fibrous membranes at the component-bone interface. Clinical significance: This multimodal imaging study contributes knowledge of the fixation of modern cementless TKA, supporting the notion that osseous integration is important for optimal implant fixation.

Manual and Device-Assisted Hamstring Autograft Tensioning Yield Similar Outcomes following ACL Reconstruction.

A prospective comparative study was conducted between September 2015 and May 2017. Sixty-four patients (mean age 29.3 years, range 14-45) with isolated ACL injuries (and who would be subjected to ACL reconstruction with a quadruple hamstring tendon graft) were divided into two groups. In Group A (n = 29), common tension was applied manually to both grafts. In Group B (n = 35), specific tension was applied to the grafts with the use of a tensioner device (ConMed Linvatec SE™ (Stress Equalization) Graft Tensioning System). A total of 60 N was applied to the semitendinosus, and 40 N was applied to the gracilis. Clinical outcomes were assessed at 6, 12, and 24 months. There were no significant differences between the baseline demographic and clinical data among the patients of the two groups (all p > 0.05). The patients were followed up for a minimum of 24 months (mean ± SD). There were no significant differences in the side-to-side anterior knee laxity, the IKDC, the Lysholm Knee, and the Tegner Activity Scale scores for up to 24 months after operation. The pivot shift test was negative in all cases, and no graft failure was reported at a 2-year follow-up. No significant differences were found with respect to postoperative anterior knee laxity, clinical outcomes, activity level, and patient satisfaction between the application of manual tension and the use of the graft-tensioning system during tibial fixation while performing anatomic single-bundle ACL reconstruction with a quadruple hamstring tendon graft. Further high-quality clinical studies are required to elucidate whether device-assisted tension is superior to manual tension.

Machine learning can accurately predict risk factors for all-cause reoperation after ACLR: creating a clinical tool to improve patient counseling and outcomes.

Identifying predictive factors for all-cause reoperation after anterior cruciate ligament reconstruction could inform clinical decision making and improve risk mitigation. The primary purposes of this study are to (1) determine the incidence of all-cause reoperation after anterior cruciate ligament reconstruction, (2) identify predictors of reoperation after anterior cruciate ligament reconstruction using machine learning methodology, and (3) compare the predictive capacity of the machine learning methods to that of traditional logistic regression. A longitudinal geographical database was utilized to identify patients with a diagnosis of new anterior cruciate ligament injury. Eight machine learning models were appraised on their ability to predict all-cause reoperation after anterior cruciate ligament reconstruction. Model performance was evaluated via area under the receiver operating characteristics curve. To explore modeling interpretability and radiomic feature influence on the predictions, we utilized a game-theory-based method through SHapley Additive exPlanations. A total of 1400 patients underwent anterior cruciate ligament reconstruction with a mean postoperative follow-up of 9years. Two-hundred and eighteen (16%) patients experienced a reoperation after anterior cruciate ligament reconstruction, of which 6% of these were revision ACL reconstruction. SHapley Additive exPlanations plots identified the following risk factors as predictive for all-cause reoperation: diagnosis of systemic inflammatory disease, distal tear location, concomitant medial collateral ligament repair, higher visual analog scale pain score prior to surgery, hamstring autograft, tibial fixation via radial expansion device, younger age at initial injury, and concomitant meniscal repair. Pertinent negatives, when compared to previous studies, included sex and timing of surgery. XGBoost was the best-performing model (area under the receiver operating characteristics curve of 0.77) and outperformed logistic regression in this regard. All-cause reoperation after anterior cruciate ligament reconstruction occurred at a rate of 16%. Machine learning models outperformed traditional statistics and identified diagnosis of systemic inflammatory disease, distal tear location, concomitant medial collateral ligament repair, higher visual analog scale pain score prior to surgery, hamstring autograft, tibial fixation via radial expansion device, younger age at initial injury, and concomitant meniscal repair as predictive risk factors for reoperation. Pertinent negatives, when compared to previous studies, included sex and timing of surgery. These models will allow surgeons to tabulate individualized risk for future reoperation for patients undergoing anterior cruciate ligament reconstruction. III.

Evaluation of Isokinetic Knee Strengths after ACL Reconstruction with Quadrupled Semitendinosus Suspensory Femoral and Tibial Fixation versus Four-Strand Semitendinosus and Gracilis Suspensory Femoral and Tibial Screw Fixation.

The purpose of this study was to demonstrate that patients undergoing ACL reconstruction with quadrupled semitendinosus suspensory femoral and tibial fixation have comparable results in muscle strength and knee function to those undergoing ACL reconstruction with four-strand semitendinosus-gracilis suspensory femoral fixation and a bioabsorbable tibial interference screw fixation. Between 2017 and 2019, 64 patients who were operated on by the same surgeon were included. Patients underwent ACL reconstruction technique with quadrupled semitendinosus suspensory femoral and tibial button fixation in Group 1, and patients underwent ACL reconstruction with coupled four-strand semitendinosus-gracilis suspensory femoral fixation and a bioabsorbable tibial interference screw in Group 2. Evaluation of patients was performed with the Lysholm and Tegner activity scale preoperatively and at the 1st and 6th months postoperatively. At the 6-month visit, isokinetic testing of the operated and non-operated limbs was performed in both groups. There was no significant difference in the age, weight, and BMI values of the patients in Groups 1 and 2 (p < 0.05). According to the strength values of the operated sides of the patients in Group 1 and Group 2, there was no significant difference in the angular velocities of 60° s-1, 180° s-1, and 240° s-1 in both extension and flexion phases between the operated sides of Groups 1 and 2 (p < 0.05). Patients who have ACL reconstruction with quadrupled semitendinosus suspensory femoral and tibial fixation have comparable muscle strength and knee function to those who undergo ACL reconstruction with four-strand semitendinosus-gracilis suspensory femoral fixation and a bioabsorbable tibial interference screw.

Tolérance de la position à genoux après enclouage centromédullaire ou fixation par plaque sans complications

IntroductionDistal tibia fractures often occur in younger, high demand patients, though the literature surrounding management remains contentious. This study sought to quantitatively determine differences in kneeling ability and self-reported knee function in patients managed with either intramedullary nailing (IMN) or open reduction internal fixation (ORIF) with compression plating following distal tibia fracture to assist in the pre-operative consent process. HypothesisThere is no difference in kneeling tolerance following either tibial nailing or plate fixation of distal tibia fractures. Material and methodsRetrospective sampling of public hospital data with outpatient prospective functional testing were completed. The primary outcome measure was the Kneeling Test (KT). Secondary outcome measures were The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the Forgotten Joint Score (FJS) for the knee joint. There were 28 patients recruited (18 IMN and 10 ORIF) with a mean age of 44 years. Mean overall follow-up was 13.3 months (range 8–25, SD 3.6). All fractures had completely healed without post-operative complication. ResultsThe IMN affected limb had a significantly worse overall kneeling function than their non-affected limb (mean KT: 70.4 vs 94.9 respectively, p<0.005) Additionally, the IMN group performed significantly worse when compared to the ORIF group (mean KT 70.4 vs 92.5 respectively, p<0.005). No significant differences (p>0.05) in kneeling function existed for the ORIF group when comparing affected to non-affected limbs. Secondary outcome analysis showed significantly worse overall WOMAC and FJS in the IMN group compared to the ORIF group (mean WOMAC 19.3 vs 6.9 respectively, p=0.040; mean FJS 38.3 vs 75.9 respectively, p=0.005). DiscussionThe use of intramedullary nailing for the treatment of distal tibia fracture results in a mean reduction of 20% in kneeling tolerance in comparison to ORIF. The resulting kneeling tolerance is comparable to that of patients post-total knee arthroplasty. The present findings should assist in the consent process for patients with high kneeling demands in sportive, professional or cultural pastimes. Level of evidenceIV; retrospective cohort study with quantitative outcome measurement.

Arthroscopic Assisted Anterior Cruciate Ligament Tibial Spine Avulsion Reduction and Cortical Button Fixation

Tibial spine avulsion fractures, or tibial eminence fractures, are intra-articular knee injuries that affect the bony attachment of the anterior cruciate ligament (ACL). It is commonly seen in children and adolescents aged 8 to 15 years old and can be caused by noncontact pivot shift injuries or by traumatic hyperextension knee injuries, as seen in adult ACL patients. A thorough history and physical exam is important in these patients alongside proper imaging that will confirm the diagnosis of a tibial spine avulsion. Proper imaging may also demonstrate other associated conditions or injuries to the cartilage, meniscus, or ligamentous structures. Following diagnosis, treatment can be both nonoperative versus operative, depending upon the degree of displacement and reducibility of the fragment, as well as other concomitant injuries. For nondisplaced or minimally displaced, and reducible injuries, the patient can be immobilized in full extension for several weeks. For displaced fragments that are unable to be reduced by closed methods, open reduction internal fixation or arthroscopic fixation is recommended. In this Technical Note, we describe an arthroscopy-assisted reduction and internal fixation with suture tape through 2 transtibial tunnels with a cortical suture button fixation technique.

Anatomic Posterolateral Corner Reconstruction With Single Graft Tibial Socket Fixation

Introduction: The posterolateral corner (PLC) is comprised of the fibular collateral ligament, popliteus tendon, and popliteofibular ligament. Injuries to the PLC are associated with significant morbidity and functional limitation, most frequently manifested through a varus thrust gait. In the previous 2 decades, advances have been made in understanding the importance of the PLC and as a result, many techniques have been developed to address its reconstruction. Material and Methods: The Laprade technique is a previously described anatomic reconstruction of the PLC. We propose some modifications to this technique, which involve dissection of the posterolateral tibia to allow direct protection of the popliteal neurovascular bundle while establishing tibial fixation. A single hamstring graft is utilized for the reconstruction, is routed through the fibular tunnel and subsequently secured with the use of a dual-expanding tenodesis anchor, placed in a tibial socket removing the need for a tibial tunnel. Conclusion: The present study describes a novel anatomic technique that allows for improved protection of neurovascular structures, better control of graft tensioning and tunnel management, and the judicious use of a single tendon autograft while maintaining the described benefits of the anatomic Laprade technique.

Comparative study of the clinical efficacy of all-inside and traditional techniques in anterior cruciate ligament reconstruction

Many studies have focused on the femoral tunnel technique and fixation method, but few studies have involved the tibial tunnel technique and fixation method. The all-inside technique is one of the new techniques that has been described in recent years. All-inside anterior cruciate ligament (ACL) reconstruction is based on a tibial socket instead of a full tunnel. This method has many potential advantages. To compare clinical outcomes of knee ACL autograft reconstruction using all-inside quadrupled semitendinosus (AIST) and traditional hamstring tendon (TBT) techniques. From January 2017 to October 2019, the clinical data of 80 patients with ACL reconstruction were retrospectively analyzed, including 67 males and 13 females. The patients had an average age of 24.3 ± 3.1 years (age range: 18-33 years). The AIST technique was used in 42 patients and the TBT technique was used in 38 patients. The time between operation and injury, operative duration, postoperative visual analogue scale (VAS) score and knee functional recovery were recorded and compared between the two groups. The International Knee Documentation Committee (IKDC) and Lysholm scoring system were used to comprehensively evaluate clinical efficacy. Eighty patients were followed for 24-36 mo, with an average follow-up duration of 27.5 ± 1.8 mo. There were no significant differences in the time between surgery and injury, operative duration, IKDC and Lysholm scores of the affected knee at the last follow-up evaluation between the two groups. There were significant differences in VAS scores 1 d, 3 d, 7 d, 2 wk and 1 mo after surgery (P < 0.05). There was no significant difference in VAS score at 3 mo, 6 mo and 1 year after operation. The efficacy of the AIST ACL reconstruction technique was comparable to the TBT technique, but the postoperative pain was less with the AIST technique. Thus, the AIST technique is an ideal treatment choice for ACL reconstruction.

The tibial tunnel drilling angles of 60° provided a lower ultimate load to failure on a single bundle posterior cruciate ligament graft using interference screw fixation compared to 30°/45°.

To biomechanically compare the initial fixation strength of grafts among three tibial tunnel angles (30°/45°/60°) in transtibial posterior cruciate ligament (PCL) reconstruction. A series of transtibial PCL reconstruction models were established with porcine tibias and bovine tendons. Specimens were randomly assigned to three groups according to the angles between the tibial tunnel and the perpendicular line of the tibial shaft: Group A (30°, n = 12), Group B (45°, n = 12), and Group C (60°, n = 12). The area of the tunnel entrance, the segmental bone mineral density (sBMD) of the graft fixation site of the tibia and the maximum insertion torque of the interference screw were measured. Finally, load to failure tests were carried out on the graft-screw-tibia constructs at the same rate. Ultimate load to failure in Group C (335.2 ± 107.5 N) was significantly lower than that in Group A (584.1 ± 127.9 N, P < 0.01) and Group B (521.9 ± 95.9 N, P < 0.01). There were no significant differences between biomechanical properties of Groups A and B (n.s.). The posterior part fractures of the tibial tunnel exit occurred in eight specimens of Group C. In addition, the ultimate load was proven to be related to insertion torque (rho = 0.7, P < 0.01), sBMD (rho = 0.7, P < 0.01), and the area of the tunnel entrance (rho =-0.4, P = 0.01). The ultimate load to failure was significantly lower in tibial PCL interference screw fixation for tunnels drilled at 60° compared to 30°/45°. In addition, the ultimate load was significantly correlated with insertion torque, sBMD and the area of the tunnel entrance. Given that the load to failure of distal fixation may not be sufficient for early postoperative rehabilitation, a 60° tunnel should not be recommended to drill in tibia during PCL reconstruction.