Bone-patellar Tendon-bone Graft Research Articles

Biomechanical comparison of Tibial-sided supplemental fixation techniques in Bone-Patellar Tendon-Bone anterior cruciate ligament reconstruction

PurposeThe purpose of this study was to compare the biomechanical properties of a commercially available suture anchor and a screw post for supplemental tibial fixation of a bone-patellar tendon-bone (BTB) graft at time zero. We hypothesized that supplemental fixation using a suture anchor would demonstrate similar biomechanical performance in comparison with a screw post. MethodsSixteen fresh frozen, healthy human cadaveric knees underwent BTB autograft harvest, placement, and primary tibial-sided interference screw fixation using a standardized technique performed by a single surgeon. Specimens were randomly assigned to one of two tibial-sided supplemental fixation groups (suture anchor or screw post), yielding eight specimens in each group. Each specimen was affixed to a custom loading apparatus, with the tibial tunnel aligned in a vertical position that allowed for parallel “worst-case scenario” loading and eliminated loading variation due to tibial tunnel angle. Grafts were pretensioned to 30 N and biomechanical performance was compared with respect to cyclical loading between 50–250 N for 500 cycles at 0.5 Hz and pull-to-failure loading at 60 mm/min. ResultsThe suture anchor and screw post supplemental constructs demonstrated similar performance with respect to all biomechanical parameters assessed, including yield strength (294.0 N [IQR 267.2–304.2 N] versus 332.1 N [IQR 313.8–350.4 N]; P = 0.079) and ultimate strength (330.1 N [IQR 306.9–418.7 N] versus 374.7 N [IQR 362.0–387.3 N]; P = 0.3798). However, of the eight original specimens in each group, one suture anchor specimen (12.5%) and six metallic screw post specimens (75%) failed during cyclical testing and were unable to undergo displacement and load to failure testing. ConclusionThis study provides preliminary evidence that supplemental tibial-sided fixation of a BTB ACL graft with a suture anchor has similar loading characteristics or load-to-failure strength when compared to supplemental fixation with a screw post construct. Study designLaboratory Controlled Study. Level of evidenceBasic Science Study.

Peroneous Longus Tendon Versus Hamstring Tendon Autograft On Anterior Cruciate Ligament Reconstruction: A Meta-Analysis and Systematic Review

Introduction: Anterior Cruciate Ligament (ACL) injury is one of the most common knee injuries. ACL reconstruction is the current gold standard to restore functional of the knee. Graft selection is important for satisfactory outcomes. Currently, most used autograft are hamstring tendon (HT) and bone patellar tendon bone (BPTB) grafts. This study aims to thoroughly evaluate and review an alternative autograft for ACL reconstruction, which is peroneus longus tendon (PLT). Method: Systematic review and meta-analysis was conducted using PRISMA guidelines. Literature was searched through PubMed, Google Scholar, Science Direct and Cochrane Library using Boolean operators. This study included original articles reporting on (1) clinical studies of ACL reconstruction (single-bundle or double-bundle) using PLT autograft (anterior-half, posterior half, or full-thickness); and (2) studies directly comparing outcomes of PLT versus HT. All procedures were primary ligament reconstructions performed for symptomatic acute or chronic ACL injury, with or without meniscal injury. The outcomes assessed included clinical and functional outcome, namely IKDC score, AOFAS scale and FADI. Results: From 247 studies obtained, after full-text review, 4 studies met all eligibility criteria. A total of 259 patients were included in this study. No significant differences was found in IKDC score (p = 0.99) and FADI score (p = 0.11) but significant differences was found in the mean of AOFAS score in favor of HT autograft (p = 0.03). Conclusion: PLT autograft is a suitable alternative graft choice from the others for the knee of patients undergoing ACL reconstruction.

Prediction of Semitendinosus Graft Length and Girth using Anthropometric Parameters: A Prospective Study in North Kerala Population

Introduction: Semitendinosus, Gracilis and Bone-Patellar Tendon-Bone (BPTB) graft are the most popular grafts for Anterior Cruciate Ligament (ACL) reconstruction. Although bone-to-bone patellar tendon grafting improves knee stability and healing rates, there are drawbacks, including donor site morbidity, patellar tendinopathy, anterior knee pain, flexion contracture, and patellar fracture. The advantages of semitendinosus graft include preservation of bone stock, the ability to triple graft length when needed, and the ability to take Gracilis graft through the same incision if graft diameter is too small. Aim: To predict the semitendinosus graft length and diameter using anthropometric parameters (height, weight, Body Mass Index (BMI), waist circumference, thigh circumference and thigh length). Materials and Methods: This prospective descriptive study was conducted in the Department of Orthopaedics, Malabar Medical College, Calicut, Kerala, India for a period of one year (from October 2021 to October 2022). A total of 50 patients in the age group 15-60 years with ACL insufficiency planned for hamstring autograft reconstruction were examined. A number of preoperative factors, including age, gender, height, weight, BMI, thigh length, thigh circumference and waist circumference were assessed. A 2-tailed test and Pearson correlation was used to identify relationships between outcome variables (semitendinosus graft length and quadrupled tendon diameter) and predictor variables (age, gender, height, weight, BMI, thigh length, thigh circumference and waist circumference). Results: A total of 68% of patients had a semitendinosus graft diameter ≥8 mm, while 32% percent were <8 mm. Compared to males, females had a lower body weight and height and their hamstring grafts were shorter with smaller diameter. Correlation analysis indicated that there was a significant positive relation between height and weight on graft length and diameter (p<0.005). Conclusion: The study concluded that both hamstring diameter and length was related to height and weight of the person. Patients who were taller and heavier might be anticipated to have grafts with longer length and larger diameter. Also, thigh and waist parameters had no impact on hamstring tendon size.

Holy Grail of ACL Reconstruction Grafts

Selection of the appropriate graft for ACL (anterior cruciate ligament) reconstruction is very important. The right choice of graft will determine the success of the surgery. For professional athletes, the primary choice remains the bone patellar tendon graft. However, sometimes there are complaints of anterior knee pain. The patellar tendon bone remains the strongest graft source for ACL reconstruction. Currently, the most popular graft used is the hamstring tendon, which consists of the semitendinosus and gracillis. The small incision makes this tendon very popular in reconstructive surgery. However, it is not uncommon for the acquired hamstring tendon size to be unpredictable and sometimes too small. The quadriceps tendon is also a good tendon of choice in the ACL reconstruction surgery. Several studies have shown the results of reconstruction with a balanced force with the patellar tendon bone. The portion of bone obtained from the superior pole of the patella, allows bone-to-bone healing. Currently, several surgeons use the peroneus longus tendon as an alternative graft option in ACL reconstructive surgery. The small incision and the relatively easy process of taking the graft, make more and more surgeons interested in using it. However, the use of the peroneus tendon should be reserved in cases of multiple ligament injury or revision cases. Further studies are needed to evaluate the long-term effects on the involved ankle. In many countries, allografts can also be used for ACL reconstruction surgery. Its preparation requires strict conditions, so that the graft condition remains good when used.

Revision Anterior Cruciate Ligament Reconstruction Using Semitendinosus Tendon With Bone Fragment

After anterior cruciate ligament (ACL) reconstruction, the tibial tunnel becomes widened over time. A revision surgery of the ACL reconstruction is required to fill the widened tunnels. Bone–patellar tendon–bone grafts often are used to fill enlarged bone tunnels. However, due to the variation in tendon length, it is often difficult to adjust the position of the bone fragment to the enlarged part of the bone tunnel. This study describes an arthroscopic ACL reconstruction technique using the semitendinosus tendon as well as a bone fragment which is placed in the enlarged tibial tunnel. The tendon and cortical bone were collected together at the tendon attachment using a flat chisel. The bone fragment was inserted through the tendon in a controlled manner and ultimately placed at the posterior wall of the tibial foramen. This technique was determined to be less invasive than using bone–patellar tendon–bone in a 2-stage revision ACL reconstruction. In addition, this technique can be easily performed by any surgeon who is accustomed to conventional ACL reconstruction using the semitendinosus tendon and does not require any special equipment. Our findings suggest that this technique may be useful for revision ACL reconstruction.

The development of long-term osteoarthritis following anterior cruciate ligament injury: reconstruction vs no reconstruction.

The high incidence of osteoarthritis (OA) in relatively young sportspeople following anterior cruciate ligament (ACL) reconstruction is concerning. Surgery is considered to reduce the development of OA compared to conservative management. This long-term study aimed to compare the incidence and severity of tibiofemoral OA (TFOA) and patellofemoral OA (PFOA) between reconstructed and non-reconstructed treatment groups and to determine which factors influence the development of OA. Fifty-six ACL-reconstructed and 45 conservatively treated patients from a cohort of 330 were followed for 11 years (mean) post-injury. Twenty-nine patients had received a bone-patellar tendon-bone (B-PT-B) graft, and 27 had received a hamstring (semitendinosus/gracilis) tendon (HT) graft. Assessment included objective and subjective stability, quadriceps and hamstring strength and radiology. Chi-square analyses compared OA between reconstructed and non-reconstructed groups and between B-PT-B, HT and non-surgical groups. Further analysis assessed the relationship between OA and age, time post-injury, meniscal injury/meniscectomy, quadriceps strength, hamstring strength, objective and subjective stability and sporting activity. Forty-eight per cent reconstructed and 53% non-reconstructed patients developed TFOA (p = 0.690). Thirty-six per cent reconstructed and 38% non-reconstructed patients developed PFOA (p = 0.831) with moderate PFOA occurring only in the non-reconstructed group. Close to significant differences (p = 0.075) were found comparing the severity of TFOA between groups with a higher incidence of moderate/severe OA in the non-reconstructed and B-PT-B groups. TFOA differed significantly between the B-PT-B and HT groups. The development of OA was related to age, time post-injury, meniscal injury/meniscectomy, quadriceps strength and subjective stability. There were no significant differences in OA incidence between reconstructed and non-reconstructed groups but fewer patients developed TFOA following HT grafting compared to B-PT-B grafting and to non-surgical treatment. Quadriceps weakness and meniscal injuries/meniscectomy, both potentially modifiable, were strongly associated with the development of TF and PFOA.

Revision ACL reconstruction using quadriceps, hamstring and patellar tendon autografts leads to similar functional outcomes but hamstring graft has a higher tendency of graft failure

PurposeThe purpose of this study was to evaluate the differences in the patient-reported functional outcomes, and graft failure in revision ACL reconstruction using quadriceps tendon (QT), Hamstring tendon (HT) and bone-patellar tendon-bone (BPTB) autografts.MethodsBetween 2010 and 2020, 97 patients who underwent revision ACL reconstruction (40 patients received a QT, 26 an HT and 31 a BPTB graft) met the inclusion criteria. Pre-injury and at 2-year postoperatively patients were evaluated for patient-reported functional outcomes; Lysholm knee score, Tegner activity level and VAS (visual analogue scale) for pain; and graft failure. Patient-reported outcomes and graft failure were compared between the QT, HT and BPTB groups. The patients with graft failure were not included for outcome analysis at 2-years of follow-up.ResultsAll three revision groups with QT, HT and BPTB autograft did not differ significantly in terms of age, sex, time from injury to surgery, concomitant injuries and single-stage or double-stage procedures (n.s.). No significant difference was found in the pre-injury patient-reported outcome; Lysholm knee score, Tegner activity and VAS for pain (n.s.) between the three groups. At the 2-year follow-up functional outcomes improved in all three groups and all the patients returned to pre-injury activity level; however, no significant difference was found in functional outcomes at the 2-year follow-up between the three groups (n.s.). Graft failure occurred in 4 (10%), 5 (19%) and 3 (10%) patients of QT, HT and BPTB groups, respectively. However, the rate of failure did not differ significantly between groups.ConclusionAll three autografts (QT, HT and BPTB) demonstrated satisfactory patient-reported outcomes in revision ACL reconstruction. Compared with QT and BPTB grafts, HT graft showed a higher tendency for failure rates. With the increasing incidence of revision ACL reconstruction, surgeons should be aware of all the available graft options. The findings of this study will assist the surgeons in the graft selection for revision ACL reconstruction.Level of evidenceLevel III.

Clinical Outcomes After Combined ACL and Anterolateral Ligament Reconstruction Versus Isolated ACL Reconstruction With Bone–Patellar Tendon–Bone Grafts: A Matched-Pair Analysis of 2018 Patients From the SANTI Study Group

Background: Bone–patellar tendon–bone (BPTB) autografts are widely considered the standard for anterior cruciate ligament reconstruction (ACLR). Purpose/Hypothesis: The aims of this study were to compare the clinical outcomes after ACLR with gold standard BPTB autografts versus combined ACLR + anterolateral ligament reconstruction (ALLR) with hamstring tendon (HT) autografts at medium-term follow-up in a large series of propensity-matched patients. The hypothesis was that combined ACLR + ALLR with HT autografts would result in lower graft rupture rates and non–graft rupture-related reoperation rates. Study Design: Cohort study; Level of evidence, 3. Methods: Patients undergoing combined ACLR + ALLR using HT autografts between January 2003 and December 2019 were propensity matched in a 1:1 ratio to patients undergoing isolated ACLR using BPTB autografts. At the end of the study period, graft ruptures, contralateral knee injuries, and any other reoperations or complications after the index procedure were identified by a search of a prospective database and a review of medical records. Results: A total of 1009 matched pairs were included. The mean duration of follow-up was 101.3 ± 59.9 months. Patients in the isolated group were >3-fold more likely to have graft failure than those in the combined group (hazard ratio, 3.554 [95% CI, 1.744-7.243]; P = .0005). Patients aged <20 years were at a particularly high risk of graft ruptures compared with patients aged >30 years (hazard ratio, 5.650 [95% CI, 1.834-17.241]; P = .0002). Additionally, there was a significantly higher reoperation rate after isolated ACLR than after combined ACLR + ALLR (20.5% vs 8.9%, respectively; P < .0001). The overall rate of subsequent contralateral ruptures was 9.1% after index surgery (isolated: 10.2%; combined: 8.0%; P = .0934), indicating that the risk profiles for both groups were similar. Conclusion: Patients who underwent isolated ACLR with BPTB autografts experienced significantly worse graft survivorship and overall reoperation-free survivorship compared with those who underwent combined ACLR + ALLR with HT autografts. The risk of graft ruptures was >3-fold higher in patients who underwent isolated ACLR using BPTB autografts.

Comparison of post-operative outcomes following anterior cruciate ligament reconstruction between patients with vs. without elevated tibial tubercle-trochlear groove (TT-TG) distance.

It is unclear if an elevated tibial tubercle-trochlear groove (TT-TG) distance is a risk factor for poor outcomes following ACLR. Therefore, the purpose of this study was to determine whether patients with an elevated TT-TG have an increased risk of retear following primary ACLR compared to controls with a normal TT-TG. All patients who underwent primary ACLR between July 2018 and June 2019 with an available preoperative magnetic resonance imaging (MRI) were eligible for inclusion. TT-TG distance was measured on preoperative MRI scans by two independent investigators. Clinical outcomes, return-to-sport rates, and Lysholm scores were compared between patients with a TT-TG < 12.5mm (normal) and those with a TT-TG ≥ 12.5mm (elevated). Overall, 159 patients were included, 98 with normal TT-TG distance and 61 with elevated TT-TG distance. Patients with an elevated TT-TG distance had worse post-operative Lysholm scores than patients with a normal TT-TG distance (83.0 vs. 95.0, p = 0.010). In patients who received a bone-patellar tendon-bone (BTB) graft, an elevated TT-TG distance was associated with higher rates of subjective instability (13.0% vs. 3.0%, p = 0.041), reoperation (13.0% vs. 1.5%, p = 0.012), and post-operative complications (25.0% vs. 8.2%, p = 0.026), as well as lower ACL psychological readiness scores (324.1 vs. 446.7, p = 0.015). Patients with an elevated pre-operative TT-TG distance have worse Lysholm scores than patients with normal TT-TG distance. Patients with an elevated pre-operative TT-TG distance who underwent ACLR with BTB grafts had significantly higher rates of subjective instability, reoperation, and post-operative complications. III.

Lateral posterior tibial slope does not affect femoral but does affect tibial tunnel widening following anatomic anterior cruciate ligament reconstruction using a Bone–Patellar Tendon–Bone graft

BackgroundTunnel widening (TW) after anterior cruciate ligament (ACL) reconstruction has been a research area of interest in ACL reconstruction. In recent years, it has been noted that posterior tibial slope (PTS) affects several types of outcomes after ACL reconstruction including TW. However, the relationships between femoral and tibial TW and between PTS and TW following anatomical ACL reconstruction using a bone–patellar tendon–bone (BTB) graft are often not understood. Therefore, the purpose of this study was to retrospectively clarify the magnitude of femoral and tibial TW and the effect of PTS on TW following anatomical ACL reconstruction using a BTB graft. MethodsA total of 111 patients who underwent isolated ACL reconstructions using BTB grafts were included in this study. Femoral and tibial tunnel aperture areas were measured using three-dimensional computed tomography (3D CT) at 1 week and 1 year postoperatively, and femoral and tibial TW (%) was calculated. Lateral and medial PTS was also measured using 3D CT. ResultsAs compared with 1 week postoperatively, the mean tibial tunnel aperture areas increased by 30.6% ± 28.5%, and the mean femoral tunnel aperture areas increased by 28.3% ± 27.9% when measured at 1 year postoperatively. Although no significant difference was observed between femoral and tibial TW, a significant positive correlation was noted between femoral and tibial TW (r = 0.240, p = 0.011). A significant correlation was observed only between lateral PTS and tibial TW (r = 0.354, p < 0.001). There was no significant correlation between medial PTS and tibial TW, lateral PTS and femoral TW, or medial PTS and femoral TW. ConclusionSignificant positive correlation was observed between femoral and tibial TW. Steeper lateral PTS correlated with greater tibial TW; on the other hand, medial PTS did not correlate with tibial TW. Although lateral PTS affected tibial TW, it did not affect femoral TW.

Bone-Patellar Tendon-Bone Autograft Harvest Prolongs Extensor Latency during Gait 2 yr after ACLR.

Bone-patellar tendon-bone (BPTB) graft harvest for anterior cruciate ligament reconstruction alters patellar tendon properties, which inflict poor quadriceps neuromuscular function. BPTB autografts are associated with higher rates of posttraumatic osteoarthritis, which in turn is associated with pathological gait. The purpose of this study was to investigate the latency between the time of peak quadriceps activity and the peak knee flexion moment during gait, between those with BPTB grafts ( n = 23) and other graft types (hamstring autograft or allografts, n = 54), 5 ± 2 months and 2 yr (25 ± 3 months) after anterior cruciate ligament reconstruction. We hypothesized that longer latencies would be observed in the BPTB graft group in the involved limb. We expected latencies to shorten over time. Knee moments and quadriceps EMG were collected during gait, and vastus medialis, vastus lateralis, rectus femoris (RF), and quadriceps latencies were calculated. Linear mixed-effects models were used to compare latencies between graft types and over the two time points. The main effects of graft type were observed for vastus medialis ( P = 0.005) and quadriceps ( P = 0.033) latencies with the BPTB graft group demonstrating longer latencies. No main effects of graft type were observed for vastus lateralis ( P = 0.051) and RF ( P = 0.080) latencies. Main effects of time were observed for RF latency ( P = 0.022). Our hypothesis that the BPTB graft group would demonstrate longer extensor latency was supported. Contrary to our second hypothesis, however, latency only improved in RF and regardless of graft type, indicating that neuromuscular deficits associated with BPTB grafts may persist 2 yr after surgery. Persistent deficits may be mediated by changes in the patellar tendon's mechanical properties. Graft-specific rehabilitation may be warranted to address the long-term neuromechanical deficits that are present after BPTB graft harvest.

ACL Graft Matching: Cadaveric Comparison of Microscopic Anatomy of Quadriceps and Patellar Tendon Grafts and the Femoral ACL Insertion Site

Background: The optimal graft choice between the bone–patellar tendon–bone (BPTB) and the quadriceps tendon remains controversial. Studies evaluating the microscopic anatomy of the quadriceps tendon–patellar bone (QTB) and BPTB grafts for anterior cruciate ligament (ACL) reconstruction are currently lacking. Hypothesis: The relationship between post–ACL reconstruction graft bending angle (GBA) and the angle corresponding to the GBA (cGBA) would indicate that the BPTB can bend more than the QTB at the femoral tunnel aperture. Study Design: Controlled laboratory study. Methods: Twenty paired human cadaveric knees fixed at <10° of knee joint flexion (mean age, 82.5 years) underwent histological sectioning and staining with Masson trichrome and toluidine blue. The femoral ACL insertion, QTB graft, and BPTB graft were microscopically analyzed. The width of the direct insertion, thickness of the uncalcified fibrocartilage and calcified fibrocartilage, ligament attachment angle, and cGBA for each group were measured. Eighteen patients who underwent ACL reconstruction with QTB or BPTB autograft were included for the evaluation of GBA using computed tomography images at 1 week postoperatively. Results: The mean insertion widths of the femoral ACL, QTB, and BPTB were 7.81, 9.07, and 6.54 mm, respectively. The QTB was 16% wider than the ACL, while the BPTB was 16% narrower than the ACL. The mean insertion thicknesses of the femoral ACL, QTB, and BPTB were 0.53, 0.94, and 0.38 mm, respectively. The QTB was 77% thicker than the ACL (P < .001), while the BPTB was 28% thinner than the ACL (P = .017). The mean ligament attachment angles of the femoral ACL, QTB, and BPTB were 20.3°, 30.2°, and 33.3°, respectively, and the QTB and the BPTB were 49% and 64% larger, respectively, than the ACL. The mean cGBAs of the femoral ACL, QTB, and BPTB were 33.9°, 35.1°, and 12.3°, respectively. The BPTB was 64% smaller than the ACL, while there was no significant difference between the QTB and the ACL. The mean GBA was 57.7°. Conclusion: The insertion width and thickness were significantly greater and smaller in the QTB and BPTB grafts, respectively, than in the ACL. The relationship between GBA after ACL reconstruction and cGBA in knee extension indicates that at the femoral tunnel aperture, the BPTB can bend more than the QTB. Clinical Relevance: QTB graft may allow more anatomic ACL reconstruction to be performed.

Revision Rates After Primary ACL Reconstruction Performed Between 1969 and 2018: A Systematic Review and Metaregression Analysis

Background:Numerous studies, including randomized controlled trials (RCTs), have been published on the optimal graft choice for primary anterior cruciate ligament (ACL) reconstruction.Purpose:To review existing studies to investigate whether advances in orthopaedics have affected revision rates after primary ACL reconstruction.Study Design:Systematic review; Level of evidence, 4.Methods:The PubMed database was searched from inception to December 31, 2020, using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Patient series, observational studies, clinical trials, and registry-based studies investigating primary ACL reconstruction were included, as were high-quality RCTs from an additional study. The minimum required follow-up time for inclusion was 1 year. The primary outcome measure was the pooled prevalence of revision ACL reconstruction. The effect of the year the surgery was performed on revision rates was evaluated with metaregression analysis. All graft types were analyzed simultaneously, and all analyses were repeated separately for each graft type.Results:Overall, 330 articles with 52,878 patients were included, with a median patient age of 28 years (range, 15-57 years). The primary ACL reconstructions were performed between 1969 and 2018. At a median of 2.3 years of follow-up, the overall revision rate was 3.14% (95% CI, 2.76% to 3.56%); it was 2.71% (95% CI, 2.25% to 3.27%) for hamstring autografts, 2.38% (95% CI, 1.82% to 3.11%) for bone–patellar tendon–bone (BPTB) autografts, and 5.24% (95% CI, 4.02% to 6.80%) for other graft types. For hamstring grafts, the revision rate increased over time (year of surgery), with a 0.0434 (95% CI, 0.0150 to 0.0718) increase effect in the logit-transformed scale for every additional year. There was a slight decrease in revision rates for BPTB (β = –0.0049; 95% CI, –0.0352 to 0.0254) and other graft types (β = –0.0306; 95% CI, –0.0608 to −0.0005) over time; however, confidence intervals for BPTB included the zero change.Conclusion:Based on this systematic review and meta-analysis, ACL reconstruction is a reliable procedure with overall low historical revision rates. BPTB autograft had the lowest revision rate and a slightly decreasing trend of failures during the past 45 years, although both BPTB and hamstring autografts are reliable graft choices.

Anterior to Posterior Bone Plug Suture Tunnels Provide Optimal Biomechanics for Bone−Patellar Tendon−Bone Anterior Cruciate Ligament Graft

PurposeTo evaluate different bone−patellar tendon−bone (BPTB) plug suture configurations for pull through strength, stiffness, and elongation at failure in a biomechanical model of suspensory fixation.MethodsForty nonpaired, fresh-frozen human cadaveric BPTB allografts with an average age of 65.6 years were tested. Tensile testing was performed with the use of a custom-designed fixture mounted in a dynamic tensile testing machine. A preload of 90 N was applied to the graft and held for 5 minutes. Following this, a tensile load-to-failure test was performed. The ultimate failure load, elongation at failure, and mode of failure were recorded, and the resulting load–elongation curve was documented.ResultsThe drill tunnel through the cortical surface (anterior to posterior) was found to be significantly stronger than the drill tunnel through the cancellous surface (medial to lateral). There were no significant differences found when comparing the strength of the suture augmentation through the tendon and the drill tunnel alone (P = .13 among cancellous groups, P = .09 among cortical groups). The cortical drill tunnel with suture augmentation through the tendon showed significantly greater elongation values (13.7 ± 3.2) at failure when compared with either the cancellous or cortical drill tunnel only test groups (P = .0003 compared with cancellous alone, P = .009 when compared with cortical alone). Conclusions: The BPTB suture configuration with an anterior to posterior–directed suture tunnel without a suture through tendon augmentation provides the optimal strength and stiffness while minimizing graft elongation after fixation in a biomechanical model. This configuration is best for preventing suture pull through and failure when passing sutures through the BPTB plug.Clinical RelevanceThis study biomechanically evaluates the optimal suture configuration in the proximal bone plug for suspensory fixation in the setting of BPTB grafts.

Paper 23: The Impact of Graft Choice on Return to Sport Testing After Adolescent ACL Reconstruction

Objectives:The number of anterior cruciate ligament (ACL) injuries and reconstructions observed in the adolescent population continues to rise. While the use of quadriceps tendon autograft has increased in popularity in this population, there remains no consensus on the ideal graft for pediatric ACL reconstruction. The objective of this study was to compare three commonly used ACL graft types with respect to i) performance on return to sport assessments and ii) timing to clearance for return to sports in an adolescent population.Methods:All patients, less than or equal to 19 years of age, who underwent reconstruction for ACL tears between 2016 and 2020 at a large, urban, academic institution were identified. Graft choice was made in a shared decision-making model with patient, parents, and surgeon. Patient demographics, laterality, graft type, time from surgery to clearance, number of physical therapy (PT) visits, and presence of concomitant meniscus injuries were collected from the electronic medical record. At a minimum of 6 months postoperatively, patients completed a formal return to sport test (RTS) including isometric strength assessments, Y- balance testing, and hop testing. Treatment cohorts based on graft type were compared with respect to RTS performance and timing to clearance. Associations between patient demographics and return to sport timing and performance were also assessed. Clearance for return to sport was determined by the treating surgeon with limb symmetry index of 90% on RTS as the goal for clearance.Results:A total of 110 adolescents, 44 female (40%), with a mean age of 16.3 years (SD, 1.7; range, 10-19) met our inclusion criteria (Table 1). Average time to first RTS assessment was 280 days (9.3 months) and average time to clearance was 371 days (12.2 months) after surgery. ACL grafts included 58 (52.7%) hamstring autografts, 26 (23.6%) bone-patellar tendon-bone (BPTB) autografts, 21 (19.1%) bone quadriceps (BQT) autografts, and 5 (4.6%) iliotibial band (ITB) autografts. ITB patients were younger on average (12.5 years old) than those receiving hamstring, BPTB or BQT grafts. There were no significant differences between groups with respect to laterality, number of physical therapy visits, or rate of concurrent meniscus surgery.Patients receiving BQT grafts were more likely to be cleared within 1 year of surgery compared to hamstring graft patients (82.4% vs. 39.6%, p=0.002) and had similar rates of clearance within 1 year compared to BPTB patients (82.4% vs. 65.2%, p=0.230). Patients with BQT and BPTB grafts both demonstrated significantly better hamstring strength symmetry compared to hamstring graft patients (5.8% strength deficit compared to healthy side vs. 1.3% vs. 29.3%, p<0.001) (Table 2). There were no differences in quadriceps strength or hop test asymmetry between graft types. Multivariate regression with age, gender, and number of PT sessions included as covariates demonstrated that hamstring graft choice was associated with decreased odds of clearance at 1 year.Conclusions:In this study of 110 adolescent ACL reconstruction patients who underwent return to sport evaluations, we found no significant difference between BPTB and BQT autografts with respect to RTS performance and time to clearance. Hamstring autograft was associated with significantly worse hamstring strength asymmetry and significantly lower rates of clearance within 1 year. Concurrent meniscus surgery, age, gender, and number of PT sessions completed prior to RTS evaluation were not significantly associated with timing of clearance or performance on the RTS assessment.Table 1.Patient Demographics and Surgical CharacteristicsTable 2.Patient Demographics and Performance by 3 Common Graft Types

Poster 205: The Effect of Increased Tibial Tubercle Trochlear Groove Distance on Post-Operative Outcomes Following Anterior Cruciate Ligament Reconstruction

Objectives:Outcomes following anterior cruciate ligament reconstruction (ACLR) are generally good/excellent. While some risk factors for poor outcomes following ACLR have been determined, there are many that remain unknown. It is unclear if an elevated tibial tubercle trochlear groove (TT-TG) distance is a risk factor for poor outcomes following ACLR. Therefore, the purpose of this study was to determine if an elevated TT-TG increases risk of failure following ACLR. The authors hypothesized that patients with an elevated TT-TG will have an increased risk of failure following ACLR.Methods:All patients who underwent primary ACLR at a single institution between July 2018-June 2019 with a minimum of 2-year follow-up were eligible for inclusion. TT-TG distance was measured on preoperative magnetic resonance imaging (MRI) scans by 2 independent investigators. Clinical outcomes, complication rates, ability to RTS, and Lysholm scores were compared between patients with a TT-TG < 12.5mm (normal) and those with a TT-TG ≥ 12.5mm (elevated). Sub-analyses comparing normal and elevated TT-TG distance were also made after isolating athletes and bone-patellar tendon-bone (BTB) graft patients.Results:Overall, 159 patients were included, 98 with normal TT-TG distance and 61 with elevated TT-TG distance. There were no differences in demographics, concomitant procedures or injury mechanism between groups. There were also no differences in rates of reinjury, post-operative complications, need for revision ACLR, or RTS rates (all p>0.05). Patients with an elevated TT-TG distance had worse post-operative Lysholm scores than patients with a normal TT-TG distance (83.0 vs. 95.0, p=0.010), and also had differing rates of subjective instability (13.1% vs. 5.1%, p=0.083) and reoperation (13.1% vs. 4.1%, p=0.060) that trended towards significant. In patients who received a bone-patellar tendon-bone (BTB) graft, an elevated TT-TG distance was associated with higher rates of subjective instability (13.0% vs. 3.0%, p=0.041), reoperation (13.0% vs. 1.5%, p=0.012), and post-operative complications (25.0% vs. 8.2%, p=0.026), as well as lower ACL psychological readiness scores (324.1 vs. 446.7, p=0.015).Conclusions:Following ACLR, patients with an elevated TT-TG distance have worse Lysholm scores with a minimum 2-year follow-up. Patients with an elevated TT-TG who underwent ACLR with BTB grafts had significantly higher rates of subjective instability, reoperation, and post-operative complications, while no differences in reinjury, complication, revision, or RTS rates were observed.Table 1.Comparison of post-operative outcomes between normal (<12.5 mm) and elevated (≥12.5 mm) tibial tubercle trochlear groove (TT-TG) distance patients. Analysis of all patients is on the left and analysis of athletes only is on the right.Table 2.Comparison of post-operative outcomes between normal (<12.5 mm) and elevated (≥12.5 mm) tibial tubercle trochlear groove (TT-TG) distance patients who received a bone-patellar tendon-bone (BTB) autograft.

Poster 256: The "N+10 Rule" to Avoid Graft Tunnel Mismatch in Bone-Patellar Tendon-Bone Anterior Cruciate Ligament Reconstruction Using Independent Femoral Tunnel Drilling

Objectives: To determine the amount of tibial graft tunnel mismatch during application of the “N+10” rule in arthroscopic assisted anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BTB) graft using independent femoral tunnel drilling.To compare actual (measured) tibial tunnel length and desired (calculated) tibial tunnel length when using the “N+10” rule for independent femoral tunnel drilling. Methods:Twenty paired knees from 10 fresh frozen cadaveric specimens (5 female and 5 male specimens) underwent arthroscopic assisted bone-patellar tendon-bone ACL reconstruction using independent femoral tunnel drilling with either a hyperflexion accessory anteromedial portal (n=10) or flexible reamer technique (n=10). The prepared patellar tendon graft bone blocks were trimmed to 10 x 20mm for all specimens and the intertendinous distance (N) between the bone blocks was measured. The “N+10 Rule” was used to set the angle of the ACL tibial tunnel guide to the appropriate degree setting for drilling. The amount of excursion or recession of the tibial bone plug in relation to the anterior tibial cortical aperture was measured in both flexion and extension. A +/-6mm threshold was used to assess this strategy based on prior biomechanical aperture fixation studies. As a secondary outcome, the intraarticular distance (IAD) and the actual tibial tunnel length (TTL) were measured and compared to the planned TTL based on the equation: IAD + TTL = N + 20 (size of bone plug in millimeters)Results:The average BTB ACL intertendinous distance (N) was 47.5mm (SD =5.5mm). The average measured IAD was 27.2mm (SD=3.0mm). Using the “N+10 Rule”, the average mismatch of the tibial tunnel was 4.9mm (SD=3.6mm) and 3.8mm (SD=3.5mm) in flexion and extension, respectively. Both values fall within the +/- 6mm threshold. When comparing the actual measured tibial tunnel length (TTL) to the desired TTL, there was an average difference of 5.4mm (SD=3.9mm)Conclusions:The “N+10” rule resulted in an acceptable average mismatch in both flexion and extension using the threshold of +/- 6mm for 20 cadaveric knees. Measured actual TTL compared to the desired calculated TTL were acceptable 61% of the time using the same threshold. The “N+10” is a simple and effective intraoperative strategy for achieving desired tibial tunnel length to avoid excessive graft tunnel mismatch.Figure 1:Derived formula for calculating ideal tibial tunnel length (TTL) using intraarticular distance (IAD), and the known values of the intertendinous distance (N) and lengths of the bone blocks (20mm).Figure 2:Intraoperative photo of BTB ACL graft measuring intertendinous distance between the bone plugs (N=55mm). Following the "N+10" ruleFigure 3:Intraoperative photo of tibial ACL guide measurement of tibial tunnel length at 50mm with guide set to 65 degrees.Figure 4:Intraoperative photo of the ACL tibial tunnel guide positioned on the anatomic tibial footprint set to 65 degrees (N=55mm). Using this setting for the guide, the tibial tunnel measured 50mm as seen in the zoomed in photo, as per the formula.

Poster 230: A Modified Lemaire Lateral Extra-Articular Tenodesis in High-Risk Adolescents Undergoing Anterior Cruciate Ligament Reconstruction: Two-Year Clinical Outcomes

Objectives:This study aimed to evaluate the safety and efficacy of performing a lateral extra-articular tenodesis (LET) with a modified Lemaire technique (MLT) in conjunction with anterior cruciate ligament reconstruction (ACLR) in children and adolescents at increased risk for failed ACLR.Methods:A consecutive series of patients ≤19 years who underwent simultaneous ACLR and LET with minimum two-year follow-up data were reviewed. Patients were indicated for LET when one or more of the following risk factors were present: participant in high-risk competitive sport such as football, lacrosse, soccer or basketball, grade 3 pivot shift, hyperlaxity (Beighton score > 6), recurvatum, revision ACLR, contralateral ACLR, or chronic ACL insufficiency. ACLR was performed using either full-thickness quadriceps tendon (QUAD) for skeletally immature patients or bone-patellar tendon-bone (BTB) autograft for skeletally mature patients. All-epiphyseal (AE) or complete transphyseal (CT) techniques were used depending on patients’ skeletal maturity. At a minimum two-year follow-up, patient-reported outcome measures included Single Assessment Numeric Evaluation (SANE), Pediatric International Knee Documentation Committee (Pedi-IKDC), and the HSS Functional Activity Brief Scale (HSS Pedi-FABS) scores. Return-to-sport (RTS) data and second surgeries were also obtained.Results:Sixty-one consecutive patients (mean age 15.17 ±1.73 years, range 11-19 years, 62% female) were analyzed (Table 1). 59 patients (97%) participated in organized sports including soccer, basketball, football and lacrosse, with soccer being the most popular one. The average grade at the time of surgery was 9th grade. Ten patients (16%) were revision ACLR procedures. Seven (11%) patients underwent AE and 54 (89%) underwent CT ACLR. Forty-two (69%) cases employed a QUAD autograft, while 19 (31%) utilized a BTB autograft. All patients underwent a LET with a MLT and 2 patients underwent simultaneous implant mediated guided growth with a plate for structural genu valgum. At two-year follow-up, mean SANE score was 95, median Pedi-IKDC score was 91, and median HSS-Pedi Fabs score was 27. RTS rate was 91.8%. Ten patients had subsequent surgical procedures, including two hardware removal procedures for hemiepiphysiodesis, three contralateral ACLR, three meniscus surgeries, one lysis of adhesions, and one revision ACLR for BTB graft re-rupture. Two patients were lost to follow-up and excluded from the study.Conclusions:The findings suggest that concomitant LET and ACLR in adolescent patients with risk factors for failed ACLR is associated with favorable patient-reported outcomes, high return to sports participation, and low ACL re-rupture rate at two years follow-up.Table 1.Patient Demographics and Surgical Characteristics.

The effects of initial graft tension on femorotibial relationship following anatomical rectangular tunnel anterior cruciate ligament reconstruction using bone–patellar tendon–bone graft

BackgroundThe purpose of this study was to elucidate the effects of the difference of initial graft tension on the femorotibial relationship on an axial plane and its chronological change following anatomical anterior cruciate ligament (ACL) reconstruction. MethodsA total of 63 patients who underwent anatomical ACL reconstruction were included in this study. The graft was fixed at full knee extension with manual maximum (higher graft tension; group H) and 80 N (lower graft tension; group L) pulls in 31 and 32 patients, respectively. The femorotibial positional relationship in axial computed tomography at 1 week and 1 year postoperatively were retrospectively evaluated. The side-to-side differences (SSDs) and the amount of changes of SSDs over 1 year were compared between groups. ResultsThe SSDs of the external rotational angle of the tibia in group H were significantly larger than those in group L at postoperative 1 week (2.7 ± 3.9° vs. 0.3 ± 3.3°; P < 0.01). The amount of internal rotational changes of SSDs of the internal–external rotational angles over 1 year in group H was significantly larger than that in group L (−3.6 ± 3.9° vs. − 0.3 ± 2.7°; P < 0.01). No significant differences were observed on the anterior–posterior translation distance and medial–lateral shift distance. ConclusionThe application of higher initial graft tension resulted in excessive external rotation of the tibia to the femur at 1 week postoperatively in anatomical ACL reconstruction, and the excessive early external tibial rotation had resolved over 1 year.

Assessment of Functional Outcome and Donor Site Morbidity in Anterior Cruciate Ligament Reconstruction Using Peroneus Longus Autograft

Introduction: Arthroscopic ACL reconstruction is one of the most successful surgeries in sports medicine. But the donor site morbidities have been reported with bone patellar tendon bone graft and hamstring tendon graft. The objective of the study is to evaluate the functional outcome of and donor site (ankle) morbidities with full thickness peroneus longus tendon (PLT) autograft in arthroscopic anterior cruciate ligament (ACL) reconstruction. Methods: A Prospective study was done in 30 patients with ACL injury. Knee stability and function were evaluated using the Lachman test, pivot shift test, International Knee Documentation Committee score (IKDC) and Lysholm knee score. Donor ankle was assessed using American Orthopedic Foot and Ankle Score (AOFAS) and grading muscle power by Medical Research Council scale. Data collected preoperatively and postoperatively at 6 &amp; 12 months were compared. Results: The IKDC score was normal or nearly normal in 24 patients and abnormal in 6 patients. The mean Lysholm score had excellent or good results in 24 patients. The Lachman test showed normal findings in 24 patients, 6 patients had 1+ laxity. The pivot-shift test was negative in 22 patients and 8 patients had 1+ glide. The mean AOFAS score was 100±0.0 (preoperatively) and 96.0±9.6 (at final follow up). No patient experienced ankle pain and instability. Conclusion: PLT autograft gave painless stable knee, with a good range of motion. It didn’t have any morbid effect on ankle and gait parameters. So, PLT autograft can be suitable graft with respect to its strength, safety and donor site morbidity. Keywords: ACL, Peroneus Longus Tendon, Knee Arthroscopy