Vertical Graft Research Articles

Change in Pulmonary Arteries after Modified Blalock-Taussig Shunt Procedure: Analysis Based on Computed Tomography.

Although the modified Blalock-Taussig shunt remains the mainstay method of palliation for augmenting pulmonary blood flow in various congenital heart diseases, the shunt must be carefully designed to achieve the best outcomes. This study investigated the effect of shunt configuration on pulmonary artery growth and growth discrepancy. Twenty patients with successful modified Blalock-Taussig shunt takedown were analyzed. Pulmonary artery and shunt characteristics were obtained using computed tomography scans. Differences in the baseline and follow-up diameter ratios and growth in the ipsilateral and contralateral arteries were calculated. The angle between the shunt and pulmonary artery, as well as the distance from the main pulmonary artery bifurcation, were measured. Correlations between pulmonary arteries and shunt configurations were analyzed. The median interval time between shunt placement and takedown was 154.5 days (interquartile range, 113.25-276.25 days). Follow-up values of the ipsilateral-to-contralateral pulmonary artery diameter ratio showed no significant correlation with the shunt angle (ρ=0.429, p=0.126) or distance (ρ=0.110, p=0.645). The shunt angle and distance from the main pulmonary bifurcation showed no significant correlation (ρ=-0.373, p=0.189). Pulmonary artery growth was negatively correlated with shunt angle (ipsilateral, ρ=-0.565 and p=0.035; contralateral, ρ=-0.578 and p=0.030), but not with distance (ipsilateral, ρ=-0.065 and p=0.786; contralateral, ρ=-0.130 and p=0.586). Shunt configuration had no significant effect on growth imbalance. The angle and distance of the shunt showed no significant correlation with each other. A more vertical shunt was associated with significant pulmonary artery growth. We suggest a more vertical graft design for improved pulmonary artery growth.

Maxillary Sinus Augmentation with Anorganic Bovine Bone Mineral of Different Particle Sizes: A Split-Mouth Study with Histomorphometric, Radiographic, and Clinical Analyses.

The aim of the present study was to compare the histomorphometrically evaluated new bone formation (NB), the radiographically measured graft stability, and the clinical implant outcome for maxillary sinus augmentation grafted with deproteinized bovine bone mineral (DBBM) with either small (Bio-Oss-S, Geistlich) or large (Bio-Oss-L, Geistlich) particles. Using a split-mouth study design, bilateral maxillary sinus augmentation was performed in 13 patients either with Bio-Oss-S particles (0.25 to 1 mm) or Bio-Oss-L particles (1 to 2 mm). After a healing period of 6 months, bone biopsies were axially retrieved in the molar region for histologic/histomorphometric analysis of NB, including subsequent staged implant placement. To determine graft stability, the maxillary sinus augmentation vertical graft heights were radiographically measured immediately after sinus augmentation, at implant placement, and at the 2- and 4-year post-augmentation follow-ups. In addition, the clinical implant-prosthodontic outcome (survival/ success/marginal bone loss) was assessed at 1 and 3 years post-loading. A total of 22 sinuses from 11 patients with split-mouth evaluation were ultimately available for data and statistical analysis. Histomorphometric analysis of the axially retrieved bone biopsies revealed the presence of NB (S: 25.5% ± 7.0% vs L: 23.6% ± 11.9%; P = .640), residual graft particles (S: 19.6% ± 9.2% vs L: 17.5% ± 6.3%; P = .365) as well as connective tissue (S: 54.9% ± 9.2% vs L: 58.9% ± 12.5%; P = .283), without significant differences between the use of small (Bio-Oss-S) and large (Bio-Oss-L) particles. However, there was significantly (P = .021) higher bone-to-graft contact (BGC) for the small-particle graft sites (27.9% ± 14.8%) compared to the large-particle graft sites (19.9% ± 12.9%), representing a significantly higher osteoconductivity. Both particle sizes showed significant (P < .01) vertical graft height reduction over time (4 years) of about 10%, with predominant graft reduction in the time period between sinus augmentation and implant placement compared to any follow-up periods after implant placement. At the 3-year post-loading implant evaluation, all implants and prostheses survived (100%), and the peri-implant marginal bone loss (S: 0.52 ± 0.19 mm; L: 0.48 ± 0.15 mm) as well as the peri-implant health conditions (S: 87.5%, L:81.2%) did not differ between implants inserted with the two different xenograft particles used. The use of small and large bovine xenograft particles for maxillary sinus augmentation provides for comparable bone formation, ensuring stable graft dimensions combined with high implant success and healthy peri-implant conditions. However, small particle size resulted in a higher BGC, providing for higher osteoconductivity than with the larger particle size.

Effect of Age and Femoral Tunnel Drilling Technique on the Prevalence of Intra-articular Pathology at Both Primary and Revision ACL Reconstruction

Background: Studies have shown that meniscal and chondral lesions are more common at the time of revision anterior cruciate ligament reconstruction (ACLR) compared with primary surgery; however, few have evaluated the same patients through both primary and revision surgery. Purpose: To describe the prevalence of meniscal and chondral lesions at the time of primary and subsequent revision ACLR and to determine the effect of age and femoral tunnel drilling technique on the development of intra-articular pathology over time. Study Design: Case series; Level of evidence, 4. Methods: All patients who had primary and subsequent revision ACLR in the same knee between 1997 and 2022 were identified from a prospectively collated database. The grading of chondral surfaces in each compartment, the presence of any meniscal tears, and treatment performed were recorded. Patients were grouped according to age and femoral tunnel drilling technique to allow subgroup analysis. Results: Overall, 262 patients were included. Median age at primary surgery was 20.2 years. Lateral meniscal tears were more prevalent than medial tears at both primary (34.7% vs 28.2%; P = .11) and revision surgery (44.3% vs 40.8%; P = .43). Chondral lesions were most frequently found on the patella (8.8%) and the medial femoral condyle (MFC; 8.0%) at primary surgery. Between surgeries, new lesions developed most commonly on the MFC (13.0%) and the lateral femoral condyle (LFC; 11.1%). It was significantly more common for lateral meniscal tears treated with repair or left in situ at primary surgery to be healed at the time of revision surgery than medial tears ( P = .01). Significantly more patients who had transtibial drilling of the femoral tunnel had a new meniscal tear at revision surgery ( P = .001). Age did not have a significant influence on the prevalence of meniscal pathology. Conclusion: The prevalence of intra-articular pathology increased between primary and revision ACLR. Lateral meniscal tears were more prevalent than medial tears at both surgeries. At revision surgery, new chondral lesions were more commonly found on the MFC than the LFC. The higher incidence of new meniscal tears observed in the transtibial group may reflect the more vertical graft orientation with this technique and its inferior ability to control rotation.

Remnant Preservation of the Primary Vertical Graft in Revision Anterior Cruciate Ligament Reconstruction.

The remnant preservation of a primary vertical graft in revision anterior cruciate ligament reconstruction (ACLR) can benefit anteroposterior stability. However, studies that address this concept are rare. To evaluate clinical outcomes of remnant preservation of primary vertical graft in revision ACLR. Cohort study; Level of evidence, 3. A total of 74 patients with revision ACLR were included in this retrospective study. Remnant preservation revision ACLR was performed only in patients with primary vertical grafts. The patients were divided into 2 groups according to whether the primary remnant vertical graft was preserved (remnant group; n = 48) or absent or sacrificed (no-remnant group; n = 26). The remnant group was further divided according to the degree of remnant tissue: sufficiently preserved subgroup (graft coverage, ≥50%; n = 25) and insufficiently preserved subgroup (graft coverage, <50%; n = 23). Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective form, Lysholm score, Tegner activity scale, manual laxity tests, and side-to-side difference in anterior tibial translation on Telos stress radiographs. The mean time to final follow-up was 40.7 ± 16.8 months. The remnant group showed more improved results in the postoperative Lachman test and Telos side-to-side difference than did the no-remnant group (P = .017 and .016, respectively). The post hoc test revealed that the side-to-side difference in laxity in the sufficiently preserved subgroup significantly outperformed that in the no-remnant group (P = .001), although no significant difference existed between the insufficiently preserved and no-remnant subgroups (P = .850). The postoperative IKDC subjective form, Lysholm score, and Tegner activity scale did not show significant differences between the 2 groups (P = .480, .277, and .883, respectively). The remnant preservation of the primary vertical graft in revision ACLR may result in better anteroposterior stability. However, subjective outcomes in the remnant group did not exceed that of the no-remnant group. The subgroup analysis revealed that only sufficiently preserved remnants demonstrated better anteroposterior stability.

Effect of Maxillary Sinus Anatomy on Bone Gain After Lateral Window Sinus Floor Elevation: A Case-Control Study

Purpose: To evaluate the effect of maxillary sinus anatomy on sinus floor elevation (SFE) operations performed with the lateral window approach. Materials and Methods: CBCT and digital panoramic radiographs were evaluated before and at least 6 months after maxillary sinus floor elevation (SFE) operations performed in 33 maxillary sinus regions in 26 patients. Maxillary sinus volume, grafted volume (GV), sinus width (SW), residual bone height (RBH), and vertical graft resorption (VGR) were calculated. The effects of RBH and SW on GV and VGR were evaluated statistically. Results: The mean GV values in the maxillary sinuses classified as narrow, average, and wide were 2.60 ± 0.57, 3.44 ± 0.65, and 3.70 ± 0.64 cm3, respectively. The mean VGR was 2.12 ± 1.67 mm, and in the sites classified as narrow, average, and wide, the mean VGR values were 1.50 ± 0.79, 1.58 ± 1.28, and 3.46 ± 2.06 mm, respectively. A statistically significant difference in GV and VGR was found between the SW groups. The mean posterior maxillary RBH was 2.30 ± 1.05 mm, and 17 and 16 sinuses were classified as ≤ 2 and > 2 mm, respectively. There was no statistically significant difference in the effect of RBH on GV or VGR. Conclusion: Although posterior maxillary RBH did not affect new bone formation in the sinuses grafted only with hydroxyapatite-derived inorganic bovine bone, with increasing SW, the GV decreased and the VGR increased.

Evaluation of the inter and intraobserver reproducibility of the “defect coverage index method”, a new computed tomography assessment method of sagittal graft positioning in arthroscopic bone block procedures

PurposeTo assess the reproducibility of a new 2-dimensional computed tomography (CT) method of assessing graft positioning in arthroscopic bone block procedure.MethodsThis is a prospective observational study. Twenty-seven patients, (all men, mean [Standard deviation] age at surgery 30.9 [8.49] years) were included. Vertical graft position was assessed on the sagittal view by measuring the amount of glenoid bone defect covered by the graft. The length of the bone defect and the amount of graft covering the defect were measured. Positioning of the graft on the sagittal plane was classified as accurate if the graft covered at least 90% of the defect. Intraobserver and interobserver reproducibility was analyzed using intraclass correlation coefficients (ICC) and Kappa coefficient with 95% confidence.ResultsExcellent intraobserver reproducibility was found, with an ICC of 0.94 (CI 95%, 0.86-0.97). Interobserver reproducibility was good, with the ICC value of 0.71, ranging from 0.45 to 0.86 (CI 95%).ConclusionThis new method of assessing graft positioning in arthroscopic bone block procedures on 2-dimensional computed tomography scans is reliable, with an excellent intraobserver and good interobserver reproducibility.Level of evidenceIII

Preoperative excessive lateral anterior tibial subluxation is related to posterior tibial tunnel insertion with worse sagittal alignment after anterior cruciate ligament reconstructions.

ObjectiveTo investigate whether preoperative lateral anterior tibial subluxation (LATS) measured from magnetic resonance imaging (MRI) can influence tibial insertion and postoperative sagittal alignment after anterior cruciate ligament reconstructions (ACLRs).Methods84 patients who underwent single-bundle ACLRs were retrospectively investigated. Among them, 39 patients (LATS of <6 mm) 23 patients (LATS of ≥6 mm and <10 mm) and 22 patients (excessive LATS of ≥10 mm) were defined as group 1, 2 and 3, respectively. LATS, the position of graft insertion into tibia as ratio of anterior-posterior width (AP ratio) and the sagittal graft angle (SGA) were postoperatively assessed from MRI at 2-year follow-up. Following linear regression analyses were employed.ResultsThe group 3 exhibited the largest preoperative LATS and remained the most postoperative LATS. Moreover, the group 3 possessed the most posteriorly located tunnel insertion with the largest AP ratio and the most vertical graft orientation. Of all included patients, a moderate correlation was demonstrated between pre- and postoperative LATS (r = 0.635). A low correlation was observed between preoperative LATS and AP ratio (r = 0.300) and a moderate correlation was displayed between AP ratio and SGA (r = 0.656).ConclusionFor ACL injuries with excessive LATS (≥10 mm), most posteriorly located tibial insertion was found out, and worse sagittal alignment containing high residual LATS was associated with more vertical graft orientation following ACLRs.

Dimensional changes of keratinized mucosa after accordion versus conventional free gingival graft around dental implants: A randomized two-arm parallel clinical trial.

Free gingival graft (FGG) is the most effective way to increase the apico-coronal width of the keratinized mucosa. In case of limited donor tissue, the accordion technique can be used. This study compared FGG for dimensional and clinical changes using accordion and conventional methods. Ninety-four implants with keratinized tissue deficiency (<2mm) were randomly assigned to treatment with accordion (49 implants) and conventional (45 implants) FGG. Endpoints including apico-coronal keratinized tissue width, vertical shrinkage, vestibular depth, probing depth, bleeding on probing, and plaque index were measured. The graft harvesting and recipient bed preparation method were similar in the two groups, and the only difference was the graft length. FGG was harvested with a length 40% shorter than the mesiodistal length of the recipient area in the accordion method and as much as the recipient area in the conventional method. vertical graft shrinkage 1, 3, and 6months following conventional graft placement was 12.04±14.99, 17.12±20.40, and 23.29±24.63 percent, respectively. In the accordion graft group, the shrinkage was significantly greater with 30.10±16.12, 36.99±15.51, and 43.75±18.78 percent at 1, 3, and 6months, respectively (p-value<.001). Other factors did not show a clinically significant difference between the two groups. Comparison of vertical shrinkage changes shows that the shrinkage rate in the accordion group is significantly higher than the conventional group. IRCT20190721044296N1 (Evaluation of dimensional changes of peri-implant attached mucosa following the treatment of free gingival graft by conventional and accordion methods; randomized clinical trial two-arm parallel).

Radiographic and Histomorphometric Evaluation of Biomaterials Used for Lateral Sinus Augmentation: A Systematic Review on the Effect of Residual Bone Height and Vertical Graft Size on New Bone Formation and Graft Shrinkage.

The aim of the present systematic review was to investigate the effect of residual bone height (RBH) and vertical bone gain on new bone formation (NBF) and graft shrinkage after lateral sinus lifts using different biomaterials. Methods: An electronic search was conducted on three databases to identify randomized controlled trials (RCTs) published until January 2021 with at least one follow-up at 6 months and at least five patients treated, comparing biomaterials used for maxillary sinus augmentation with a lateral approach. Graft volumetric changes, RBH, vertical bone gain, implant failure, and post-operative complications were evaluated. The risk of bias was assessed using the Cochrane tool. Results: We used 4010 identified studies, of which 21 were RCTs. Overall, 412 patients and 533 sinuses were evaluated. Only three publications had an overall low risk of bias. After 6 months, xenograft (XG) showed the least volume reduction (7.30 ± 15.49%), while autogenous graft (AU) was the most reabsorbed (41.71 ± 12.63%). NBF appeared to not be directly correlated with RBH; on the contrary, the overall linear regression analysis showed that NBF significantly decreased by 1.6% for each mm of postoperative vertical graft gain. This finding suggests that the greater the augmentation, the lower the NBF. A similar tendency, with a regression coefficient even higher than the overall one, was also observed with alloplast (AP) and XG. Conclusions: The present results suggested that NBF was essentially independent of preoperative bone height. On the contrary, the smaller the volume was of the graft placed, the higher the amount of new bone formed, and the smaller the graft shrinkage was. Minimizing the augmentation volume might be beneficial to graft healing and stability especially when using AP and XG.

Anterior Cruciate Ligament Graft Tunnel Placement and Graft Angle Are Primary Determinants of Internal Knee Mechanics After Reconstructive Surgery

Background: Graft placement is a modifiable and often discussed surgical factor in anterior cruciate ligament (ACL) reconstruction (ACLR). However, the sensitivity of functional knee mechanics to variability in graft placement is not well understood. Purpose: To (1) investigate the relationship of ACL graft tunnel location and graft angle with tibiofemoral kinematics in patients with ACLR, (2) compare experimentally measured relationships with those observed with a computational model to assess the predictive capabilities of the model, and (3) use the computational model to determine the effect of varying ACL graft tunnel placement on tibiofemoral joint mechanics during walking. Study Design: Controlled laboratory study. Methods: Eighteen participants who had undergone ACLR were tested. Bilateral ACL footprint location and graft angle were assessed using magnetic resonance imaging (MRI). Bilateral knee laxity was assessed at the completion of rehabilitation. Dynamic MRI was used to measure tibiofemoral kinematics and cartilage contact during active knee flexion-extension. Additionally, a total of 500 virtual ACLR models were created from a nominal computational knee model by varying ACL footprint locations, graft stiffness, and initial tension. Laxity tests, active knee extension, and walking were simulated with each virtual ACLR model. Linear regressions were performed between internal knee mechanics and ACL graft tunnel locations and angles for the patients with ACLR and the virtual ACLR models. Results: Static and dynamic MRI revealed that a more vertical graft in the sagittal plane was significantly related (P < .05) to a greater laxity compliance index (R2 = 0.40) and greater anterior tibial translation and internal tibial rotation during active knee extension (R2 = 0.22 and 0.23, respectively). Similarly, knee extension simulations with the virtual ACLR models revealed that a more vertical graft led to greater laxity compliance index, anterior translation, and internal rotation (R2 = 0.56, 0.26, and 0.13). These effects extended to simulations of walking, with a more vertical ACL graft inducing greater anterior tibial translation, ACL loading, and posterior migration of contact on the tibial plateaus. Conclusion: This study provides clinical evidence from patients who underwent ACLR and from complementary modeling that functional postoperative knee mechanics are sensitive to graft tunnel locations and graft angle. Of the factors studied, the sagittal angle of the ACL was particularly influential on knee mechanics. Clinical Relevance: Early-onset osteoarthritis from altered cartilage loading after ACLR is common. This study shows that postoperative cartilage loading is sensitive to graft angle. Therefore, variability in graft tunnel placement resulting in small deviations from the anatomic ACL angle might contribute to the elevated risk of osteoarthritis after ACLR.

One-Stage Vertical Ridge Augmentation and Dental Implantation With Allograft Bonerings: Results 1 Year After Surgery.

The aim of this study was to analyze the success rate of dental implants and the graft shrinkage rate after vertical ridge augmentation and simultaneous implantation with an allograft bonering. Fifty-one patients (81 augmentations and simultaneous implantations) were included. The bonering technique followed a standardized protocol. The alveolar ridge was prepared using a congruent trephine, and depending on the defect size, an allograft bonering with an outer diameter of 6-7 mm was placed. The height of the bonering was trimmed with a diamond disc to the required length. The average height of vertical augmentation was 5.5 mm. Implants were inserted through the bonering into the native bone of alveolar ridge. After 6 months, dental implants were exposed, and dental prosthetics were placed. Of 81 implants placed with the bonering technique, two failed during a 12-month follow-up, corresponding to a success rate of 97.5%. One year after surgery, the allograft bonering exhibited an average vertical graft shrinkage rate of 8.6%. In conclusion, the allograft bonering technique was associated with a favorable outcome, and in cases with large vertical defects, both treatment time and donor site morbidity could be reduced.

Evaluating the Reliability Of MRI In Predicting The Degree Of ACL Tears In Pre-operative Planning For The Surgical Treatment Of ACL Tears: A Retrospective Study

Objectives: Anterior cruciate ligament (ACL) repair has regained interest in recent years as it has been demonstrated to provide favorable outcomes in patients with proximal ACL tears or avulsions. Magnetic resonance imaging (MRI) is the primary method uses to pre-operatively evaluate the ACL injury and help decide whether to perform an ACL repair or reconstruction. However, intraoperative findings often do not correspond with the MRI findings. This discrepancy may cause the surgeon to deviate from their initial surgical plan. Furthermore, some surgeons may disregard the possibility of performing an ACL repair solely due to the MRI report. Thus, potential candidates for ACL repair may be ignored due to the MRI report. This study aims to evaluate the reliability of MRI in predicting the degree of ACL tears planning for surgical treatment. Methods: We reviewed patients that underwent ACL repairs by a single surgeon at our institution between June 2015 to August 2018. All patients were initially seen for an ACL injury and were consulted for both ACL reconstruction and ACL repair. The final treatment decision was made following diagnostic arthroscopy. An ACL repair was performed only if the patient had a proximal tear, an intact but vertical ACL graft from a previous ACLR, or a tibial spine avulsion. Any patients that were missing MRI reports or operative reports were excluded. Pre-operative MRI of sagittal views of the ACL were then reviewed by a single radiologist and rated on integrity of the ligament’s midsubstance, and its tibial and femoral attachments. Intraoperative reports were then compared with the MRI reports. Results: We identified 40 consecutive ACL repairs of which 25 were included. Fifteen patients were excluded due to missing either operative or MRI reports. Of the included patients, 16 were males (64%) and the mean ± SD of age was 33.5±9.5 years (range 14-50 years). Two patients also had previous ACL reconstructions that failed and were subsequently revised with an ACL repair. MRIs demonstrated 15 full thickness tears with 9 torn at midsubstance, 2 torn at the tibial attachment, and 4 torn at the femoral attachment. Nine were reported as partial tears, with 4 torn at midsubstance, 2 torn at tibial attachment, and 3 torn at femoral attachment. One MRI reported no tear present. Intraoperatively, the surgeon identified 11 full-thickness tears, 11 partial tears, 2 tibial spine avulsions, and 2 incidences where a previous ACL reconstruction had failed due to a vertical graft. All of the full-thickness and partial tears were at the femoral attachment. The overall MRI sensitivity for the presence of an ACL injury was 96% with 2 false positives (8%), both of which revisions for failed ACLR. The overall accuracy was 32%, with specificity for tear-degree and tear-location 44% and 36%, respectively. Conclusion: Our results suggest that MRI may not be completely reliable in assessing the degree and location of an ACL tear. Furthermore, our results demonstrate that some patients who had repairable ACLs had MRI reports that suggested otherwise. Thus, our findings suggest that the surgeon should not solely rely on MRI imaging for ruling out possible ACL repair. This may also suggest that diagnostic tools, such as in-office diagnostic arthroscopy, be used in conjunction with MRI to more accurately assess the nature of an ACL tear. Future prospective studies with a larger sample size are necessary to confirm our findings that MRI may be less reliable for assessing ACL repair candidates.

TECHNOLOGY OF ANATOMICAL RECONSTRUCTION OF THE ANTERIOR CRUCIATE LIGAMENT OF THE KNEE JOINT: OPPORTUNITIES AND BENEFITS

The objective is to study the technologies of AM portal ACL-R and antegrade outside-in ACL-R, to give a description and scientifically grounded recommendations for their clinical application. Material and method. 114 operations were analyzed. AM portаl ACL-R was performed in 39 cases (34.2 %) (1a subgroup) and antegrade outside-in ACL-R was performed in 37 cases (32.5 %) (1b subgroup).Transtibial ACL-R was performed in 38 cases (33.3 %) (group 2). Results. In the 1 group, stability and knee function was higher, the vertical graft position, its postoperative destruction or dilatation of the bone channels was less often observed (p&lt;0.01). Nevertheless, the intraoperative time in the 2nd group was less (p&lt;0.05). Conclusions. The anatomical ACL-Rs make possible to obtain greater reliability in achieving excellent and good results in comparison with the transtibial technique.

Anterior Cruciate Ligament Soft Tissue Graft Fixation in the Elderly: Is There a Reason to Use Interference Screws? A Human Cadaver Study

To analyze the ultimate failure load, yield load, stiffness, and cyclic resistance of different anterior cruciate ligament (ACL) soft tissue graft fixation techniques in osteopenic bone. In this study, 24 fresh-frozen human cadaveric tibiae (mean age 82.6years; range 56-96; 6 male and 6 female donors) were used. Quantitative computed tomography was performed to match bone density. Looped porcine flexor tendon grafts were chosen as ACL graft substitutes for tibial graft fixation techniques (n= 8 each): (1) hybrid fixation with an interference screw and extracortical button fixation; (2) extracortical button fixation; and (3) interference screw fixation. In single cycle mode, constructs were loaded to failure to evaluate stiffness, yield load, and maximum load. In cyclic testing, 2,000 cycles (25-100N) were applied followed by loading to failure. A 1-way analysis of variance was performed with significance set at P= .05. Hybrid fixation resulted in significantly higher yield load (283.4 ± 86.19N; P= .0037) and maximum load (407.9 ± 102.3N; P= .0026) than interference screw fixation (yield load 176.4 ± 26.03, max load 231.8 ± 94.06N) in elderly bone. Yield load after extracortical button fixation (252.9 ± 41.97N; P= .0286) was also higher than that after interference screw fixation, but stiffness (18.98 ± 9.154N/mm; P= .0041) was less than that after hybrid fixation (37.28± 13.53N/mm). Of 8 specimens in the interference screw group, 7 did not survive 2,000 cycles and failed by graft slippage, whereas all other specimens in both other groups survived. Tibial hybrid fixation of ACL soft tissue grafts provides less vertical graft movement than extracortical button fixation and higher primary failure loads than interference screw fixation in elderly bone. In this elderly human joint invitro model, tibial hybrid fixation provides biomechanical advantages over other techniques. Graft fixation with only an interference screw should be avoided in osteopenic bone.

Does Anteromedial Portal Drilling Improve Footprint Placement in Anterior Cruciate Ligament Reconstruction?

Considerable debate remains over which anterior cruciate ligament (ACL) reconstruction technique can best restore knee stability. Traditionally, femoral tunnel drilling has been done through a previously drilled tibial tunnel; however, potential nonanatomic tunnel placement can produce a vertical graft, which although it would restore sagittal stability, it would not control rotational stability. To address this, some suggest that the femoral tunnel be created independently of the tibial tunnel through the use of an anteromedial (AM) portal, but whether this results in a more anatomic footprint or in stability comparable to that of the intact contralateral knee still remains controversial. (1) Does the AM technique achieve footprints closer to anatomic than the transtibial (TT) technique? (2) Does the AM technique result in stability equivalent to that of the intact contralateral knee? (3) Are there differences in patient-reported outcomes between the two techniques? Twenty male patients who underwent a bone-patellar tendon-bone autograft were recruited for this study, 10 in the TT group and 10 in the AM group. Patients in each group were randomly selected from four surgeons at our institution with both groups demonstrating similar demographics. The type of procedure chosen for each patient was based on the preferred technique of the surgeon. Some surgeons exclusively used the TT technique, whereas other surgeons specifically used the AM technique. Surgeons had no input on which patients were chosen to participate in this study. Mean postoperative time was 13 ± 2.8 and 15 ± 3.2 months for the TT and AM groups, respectively. Patients were identified retrospectively as having either the TT or AM Technique from our institutional database. At followup, clinical outcome scores were gathered as well as the footprint placement and knee stability assessed. To assess the footprint placement and knee stability, three-dimensional surface models of the femur, tibia, and ACL were created from MRI scans. The femoral and tibial footprints of the ACL reconstruction as compared with the intact contralateral ACL were determined. In addition, the AP displacement and rotational displacement of the femur were determined. Lastly, as a secondary measurement of stability, KT-1000 measurements were obtained at the followup visit. An a priori sample size calculation indicated that with 2n = 20 patients, we could detect a difference of 1 mm with 80% power at p < 0.05. A Welch two-sample t-test (p < 0.05) was performed to determine differences in the footprint measurements, AP displacement, rotational displacement, and KT-1000 measurements between the TT and AM groups. We further used the confidence interval approach with 90% confidence intervals on the pairwise mean group differences using a Games-Howell post hoc test to assess equivalence between the TT and AM groups for the previously mentioned measures. The AM and TT techniques were the same in terms of footprint except in the distal-proximal location of the femur. The TT for the femoral footprint (DP%D) was 9% ± 6%, whereas the AM was -1% ± 13% (p = 0.04). The TT technique resulted in a more proximal footprint and therefore a more vertical graft compared with intact ACL. The AP displacement and rotation between groups were the same and clinical outcomes did not demonstrate a difference. Although the AM portal drilling may place the femoral footprint in a more anatomic position, clinical stability and outcomes may be similar as long as attempts are made at creating an anatomic position of the graft. Level III, therapeutic study.

Graft Remodeling following Transcrestal Sinus Floor Elevation via the Gel-Pressure Technique (GPT) and Pasteous Nano-Crystalline Hydroxyapatite Bone Substitute

Bone grafting of the maxillary sinus is attempted to compensate for sinus pneumatization and permit reliable insertion of endosseous dental implants for prosthetic rehabilitation. The aim of the present clinical investigation was to study bone regeneration four months after transcrestal sinus floor elevation via the Gel-Pressure Technique (GPT) and application of pasteous nano-crystalline hydroxyapatite bone substitute. A total of 25 patients with deficient alveolar ridges in the posterior maxilla (mean residual bone height: 4.7 ± 1.8 mm) were subjected to 32 flapless transcrestal sinus floor augmentations and simultaneous insertion of 40 implants. Sinus membrane elevation height averaged 11.2 ± 2.7 mm and minimal vertical graft resorption of 0.1 mm was observed after four months. Radiographic bone density averaged 460 Hounsfield units in regions adjacent to the native jawbone (1 to 7 mm distance), while reduction of bone density by −7.2%, −11.3%, −14.8%, −19.6% and −22.7% was recorded in more apical regions of 8, 9, 10, 11, and ≥12 mm distance to the original sinus floor, respectively. The results suggest that graft remodeling is completed up to a distance of 7 mm within a healing period of four months after sinus augmentation using nano-crystalline hydroxyapatite bone substitute material.

Kinematics and Contact Stress Analysis of Pediatric Anterior Cruciate Ligament Reconstructions: Do the All-Epiphyseal and Complete Transphyseal Reconstructions Restore Anterior and Rotational Stability?

Objectives:Pediatric ACL reconstruction techniques have been described that can restore stability and contact pressures to the ACL deficient knee. The complete transphyseal (CT) reconstruction uses a more vertical graft to minimize physeal damage whereas the all-epiphyseal (AE) reconstruction uses sockets beginning at the ACL footprint and avoids the physis. The CT reconstruction may leave the knee unstable against pivot shift loads and leave contact stress abnormalities, whereas the AE may better resist rotational loads. A direct comparison of the kinematics and contact stresses after AE and CT ACL reconstructions have not been studied.Hypotheses:Both the AE and CT reconstructions will restore translational kinematics but the AE technique will better restore rotational kinematics. The AE reconstruction will more closely replicate the contact stresses of the ACL intact knee compared to the CT reconstruction because of the restoration of rotational stability.Methods:Seven fresh-frozen human cadaveric knees were tested using a robotic manipulator. Each of the specimens was tested with the intact ACL, the deficient ACL, and after each reconstruction. The AE utilized sockets oriented within the epiphysis. The CT had more central and vertical sockets in both the tibia and femur. Both reconstructions were fixed with suspensory cortical fixation devices using an all-inside technique and 10 mm diameter hamstring grafts. Reconstruction order was randomized. Anterior stability was assessed with 134N anterior force at 30, 90° of knee flexion simulating the Lachman and anterior drawer exams, respectively. The pivot shift exam was simulated by applying a combined 8 Nm and 4 Nm of abduction and internal rotation, respectively, at 15° of knee flexion. Tibiofemoral motions were recorded and mean contact stresses generated within the tibiofemoral compartments were measured using contact stress transducers. Outcomes were compared across conditions of the ACL using ANOVA and Kruskall-Wallis for normally and non-normally distributed data, respectively.Results:Both reconstructions had significantly decreased anterior translation, medial translation, and internal rotation compared to the ACL deficient knee (Figure 1) in response to loads simulating the pivot shift. However, internal rotation and medial translation remained elevated beyond intact levels following the CT reconstruction by 10.5% (P<0.05) and by 75.3% (P<0.05), respectively. During the simulated anterior drawer test at 30° and 90° of knee flexion both reconstructions restored anterior translation to that of the ACL intact knee. In response to the pivot-shift, the AE reconstruction decreased lateral posterior contact stresses compared to the ACL-deficient knee. However, following CT reconstruction, they remained elevated compared to the ACL-competent knee (P<0.05). Both reconstruction techniques offloaded the posterior aspect of the medial tibial plateau compared to the ACL deficient knee in response to anterior loading at 30 and 90° of knee flexion.Conclusion:While both AE and CT reconstructions reduced anterior translations and posteromedial contact stresses in response to an anterior load, the AE technique more effectively reduced axial rotation and posterolateral contact stresses during a simulated pivot shift exam. These findings are likely due to the more oblique orientation of the AE graft, which makes it a more effective stabilizer to rotational and medial-lateral loads.

Disadvantages and Advantages of Transtibial Technique for Creating the Anterior Cruciate Ligament Femoral Socket

Anterior cruciate ligament (ACL) femoral socket techniques have distinct advantages and disadvantages when considering the following techniques: transtibial, anteromedial portal, outside-in, and outside-in retroconstruction. There is no one perfect technique and we have an incomplete understanding of anatomical, biomechanical, isometry, stability, and clinical outcomes. Our primary focus is transtibial technique for creating the ACL femoral socket. Advantages include less invasive, isometric graft placement, stable Lachman exam, and minimal graft impingement with the tunnel and notch. Disadvantages include nonanatomic vertical graft placement that can cause rotational instability and positive pivot shift, interference screw divergence, graft-tunnel length mismatch, femoral socket constraint, posterior cruciate ligament impingement, and a short, oblique tibial tunnel that may undermine the medial plateau in an attempt to achieve anatomic ACL reconstruction.

The surgical management of angiosarcoma of the breast—a single institution experience

Angiosarcoma of the breast is a rare and aggressive tumour of the vascular endothelium. It may arise spontaneously or secondary to radiation. We present our experience of managing breast angiosarcoma, the largest single institution case series from the UK to date along with a summary of the relevant literature. Data on all patients with breast angiosarcoma treated in our unit were prospectively recorded (2002–2014). Demographics, surgical details and outcomes were analysed. Eighteen female patients presented with breast angiosarcoma. Sixteen patients previously underwent adjuvant radiotherapy following surgery for breast carcinoma; the mean duration between radiotherapy and angiosarcoma development was 8.4 years (range 3–21). Resections were as follows: radical mastectomy (n = 14), simple mastectomy (n = 1) and wide local excision (n = 3). Reconstruction was undertaken as follows: pedicled lattisimus dorsi (LD) musculocutaneous flap (n = 5), pedicled LD muscle flap and split skin graft (n = 7), free deep inferior epigastric perforator (DIEP) flap (n = 1), pedicled vertical rectus abdominus muscle (VRAM) flap and split skin graft (n = 1), pedicled LD muscle and pedicled VRAM muscle flaps and split skin graft (n = 1), pedicled LD muscle and pedicled (contralateral) pectoralis major muscle flaps and split skin graft (n = 1) and direct closure (n = 2). Three patients developed local recurrence; mean duration from resection to recurrence was 12 months (range 9–19). Three patients developed metastasis. Seven patients (38.8 %) died; median survival from presentation was 19 months (range 2–55 months). The remaining eleven patients remain well with no disease recurrence; mean follow-up was 38 months (range 4–125). The estimated 5-year survival (Kaplan-Meier equation) in our cohort was 49 %. Breast angiosarcomas are rare and challenging to manage. Successful outcomes can be achieved by early, aggressive resection and appropriate reconstruction. Level of Evidence: Level IV, therapeutic study.

Add a third dimension to your patient care with cone beam computed tomography

Cone-beam computed tomography (CBCT) has been specifically designed to produce undistorted three-dimensional information of the maxillofacial skeleton, including the teeth and their surrounding tissues with a significantly lower effective radiation dose compared with conventional computed tomography. The revolutionary introduction of CBCT in all fields of dentistry is unprecedented as it has created a true paradigm shift from a conventional two-dimensional approach to a three-dimensional understanding. In doing so it has expanded the role of imaging from its traditional one in diagnosis to image guidance of operative and surgical procedures. Clinical Relevance To Interdisciplinary Dentistry Detecting anatomical variants such as accessory neurovascular canals, bony undercuts, and local alterations in trabecular patterns, all of which influence implant treatment planning Identification of root canal system anomalies and determination of root curvature for successful endodontic practice Cone beam computed tomography, offers an opportunity to see inside the bone and pinpoint and measure densities in small localized areas such as a vertical periodontal defect or alveolar bone graft Three-dimensional and cross-sectional evaluation of the implant patient and it allows virtual implant placement that can guide the implantologist in terms of density and thickness of the alveolar bone.