Abstract
Background:
There are limited comparisons of graft configurations and fixation methods for the all‐inside anterior cruciate ligament (ACL) technique based on a laboratory investigation.
Purpose/Hypothesis:
This review aimed to evaluate the biomechanical data from controlled laboratory studies on different graft configurations and fixation methods in correlation to graft strength and stability in all‐inside ACL reconstruction. It was hypothesized that graft configuration and supplementary fixation would significantly contribute to graft strength and stability.
Study Design:
Scoping review.
Methods:
A literature search was conducted via PubMed on January 15, 2025, including studies that examined all‐inside ACL graft techniques in a controlled biomechanical manner; reported data on stiffness and/or ultimate load to failure, and utilized cadaveric, porcine, or bovine tendons with cyclic loading and pull‐to‐failure testing protocols. A total of 150 studies were shortlisted before being narrowed down to 11 biomechanical studies, with descriptive statistical analysis performed.
Results:
This review demonstrated that quadrupled ACL grafts outperformed tripled grafts in stiffness and load to failure. Adjustable-loop devices provided robust primary fixation, while supplementary fixation further enhanced graft stability. Overall, 3 failure modes emerged: graft failure, fixation failure, and suture failure, directly linked to surgical technique choices. Findings established evidence‐based benchmarks for optimizing all‐inside ACL reconstruction outcomes.
Conclusion:
Our search and review demonstrated that a quadruple‐folded graft with the side‐to‐side suturing technique, suspended by 2 adjustable‐loop devices with additional tensioning and knot tying, and supplementary fixation with tibial reinforcement appears to offer the most stability. This has the potential to optimize functional recovery after ACL reconstruction via improved graft stability and reduced rerupture rates.
Keywords: biomechanics, all-inside, ACL, graft preparation
Anterior cruciate ligament (ACL) reconstruction is a common procedure in orthopaedic surgery, aimed at restoring knee joint stability and function after a rupture. The ACL is critical for knee kinematics; thus, an ACL injury often results in significant functional impairment, especially in active patients and athletes.2-4,9,10,12,18-21,24
Over the past decade, the socket‐based all-inside ACL reconstruction technique has gained popularity among surgeons because of its minimally invasive approach, which results in the possibility of reduced postoperative pain and downtime, leading to faster recovery and potentially superior clinical outcomes compared with traditional tunnel‐based techniques.6,11 An important factor that influences the outcomes of the all‐inside ACL technique is graft configuration, such as a triple- or quadruple‐folded semitendinosus tendon autograft. 6 Another factor that contributes to successful ACL reconstruction is fixation method, as it directly affects postoperative mechanical stability of the graft, graft integration, and long‐term clinical outcomes. 7 Numerous biomechanical studies have examined different fixation methods, suturing techniques, and graft preparation techniques to determine the most effective approach for ensuring a robust graft and long‐term function. Currently, there is no general consensus on the ideal graft configuration or fixation method.2-4,9,10,12,18-21,24 This review aimed to synthesize biomechanical data from various laboratory studies to provide an overview of graft strength and stability in terms of graft configurations and fixation methods to guide surgeons in their choice of graft preparation techniques for all‐inside ACL reconstruction. We hypothesized that in all‐inside ACL reconstruction, a quadruple‐folded graft secured with side‐to‐side suturing and reinforced with supplementary fixation would demonstrate significantly higher ultimate loads to failure and stiffness compared with a triple‐folded or unsecured graft on biomechanical testing.
Methods
Approval from an ethics board or informed consent from patients was not required for this study, as only controlled laboratory studies were included in this review.
Literature Search
A literature search was conducted via the PubMed database, analyzing studies on the biomechanics of all‐inside ACL reconstruction from January 2010 to January 2025. The search terms included synonyms and terms related to “biomechanics” and “all-inside ACL reconstruction surgery.” A manual search of relevant articles and bibliographies was then performed.
Study Selection
There were 2 orthopaedic surgeons who independently selected articles for a full‐text review based on the article's title and abstract. Studies were included if they examined all‐inside ACL graft techniques in a controlled biomechanical manner; contained data on the graft's stiffness and/or ultimate load to failure; and used cadaveric, porcine, or bovine tendons with cyclic loading and pull‐to‐failure testing protocols. Studies that did not primarily address biomechanical outcomes or were formatted as a review article or letter to the editor were excluded. To minimize the risk of including duplicate data, all selected studies were screened for overlapping authorship, study period, and specimen or graft characteristics. If potential duplication was suspected, only the most complete or recent version of the dataset was included. Disagreements between the reviewers during study selection or data extraction were resolved by a consensus.
Data Extraction
Data on stiffness, ultimate load to failure, mode of failure, and graft configuration (number of cerclage sutures used, type of end‐to‐end stitching, graft length and diameter) as well as testing protocols were extracted from each article. The data are summarized in Appendix Table A1. Heterogeneity was qualitatively assessed by comparing study variables including graft type (cadaveric, porcine, bovine), graft configuration (number of cerclage sutures used, type of end‐to‐end stitching, graft length and diameter), stiffness, ultimate load to failure, fixation method (primary or supplementary fixation), and testing protocol (eg, cyclic loading range and cycles, mode of failure). Joint stability and kinematics were not examined in these 11 studies. Because of significant methodological variation, statistical measures of heterogeneity were not applicable, and a meta‐analysis was not performed. Descriptive statistical analysis was performed in this review instead.
Results
The electronic search of PubMed yielded 150 articles, as seen in Figure 1. Title screening was conducted, and this process excluded another 84 articles. Then, 66 abstracts were screened down to a total of 12 relevant studies. One article was excluded because of a different overall scope of the study, which was less relevant to our analysis of the biomechanics of the all‐inside ACL graft technique. The 11 studies that were included for a review investigated various aspects of the all‐inside ACL graft technique.2-4,9,10,12,18-21,24 The studies utilized cadaveric, porcine, or bovine tendons and employed cyclic loading and pull‐to‐failure testing protocols to evaluate biomechanical performance. The key data extracted from each study, including stiffness, ultimate load to failure, mode of failure, and graft configuration, are summarized in Tables 1 to 3 and Appendix Table A1. Because of methodological heterogeneity (eg, different graft types and varied testing protocols in each study), a qualitative synthesis was performed instead of a meta‐analysis.
Figure 1.
Flow diagram of the literature search.
Table 1.
Areas of Investigation
Table 3.
Testing Protocols
| First Author (Year) | Mode of Failure | Testing Protocol | Type of Specimen | Testing Machine |
|---|---|---|---|---|
| Bachmaier 2 (2023) | Suture failure, fixation failure | Cyclic loading (50-300 N, 3000 cycles), pull to failure (50 mm/min) | Bovine tendon, porcine tendon | ElectroPuls E10000 (Instron) with custom clamps |
| Barrera 3 (2019) | Suture failure, graft failure, fixation failure | Load to failure in displacement‐control (no cyclic loading) | Human cadaveric tendon | ElectroPuls E3000 (Instron) with custom‐slotted plates |
| Bowes 4 (2020) | Suture failure, graft failure, fixation failure | Cyclic loading (50-250 N, 500 cycles), pull to failure (20 mm/min) | Porcine tendon | ElectroForce 3510 (TA Instruments) |
| Graf-Alexiou 9 (2021) | Suture failure, fixation failure | Cyclic loading (50-250 N, 500 cycles), pull to failure (20 mm/min) | Porcine tendon | ElectroForce 3510 (TA Instruments) |
| Liu 10 (2025) | Suture failure | Cyclic loading (50-250 N, 500 cycles), pull to failure (20 mm/min) | Porcine tendon | HTS-LLY2510A (ZYJK Precision Instrument) |
| Mayr 12 (2016) | Graft failure, fixation failure | Cyclic loading (50-250 N, 1000 cycles), load to failure (50 mm/min) | Bovine tendon | Mini Bionix 858 (MTS Systems) |
| Richardson 18 (2019) | Graft failure, fixation failure | Cyclic loading | Bovine tendon | Mini Bionix II 808 (MTS Systems) |
| Tiefenboeck 19 (2019) | Suture failure, fixation failure | Cyclic loading (50-250 N, 500 cycles), load to failure | Human cadaveric tendon | Z050 (Zwick Roell) |
| Wichern 20 (2018) | Suture failure, graft failure | Cyclic loading (50-250 N, 500 cycles), load to failure (20 mm/min) | Porcine tendon | Mini Bionix 858 (MTS Systems) |
| Wicks 21 (2022) | Graft failure, fixation failure | Cyclic loading (50-250 N, 500 cycles), load to failure (20 mm/min) | Porcine tendon | ElectroPuls E10000 (Instron) with custom rig |
| Yoo 24 (2019) | Suture failure, graft failure | Cyclic loading (50-250 N, 1000 cycles), load to failure (50 mm/min) | Bovine tendon | Bionix 858 (MTS Systems) |
Graft preparation techniques ranged between articles, with 6 studies that investigated graft configuration only,9,10,18-20,24 comparing between tripled and quadrupled grafts as well as suturing techniques to enhance the mechanical strength of the graft. There were 3 studies that focused solely on supplementary fixation,2,3,21 such as the use of suture anchors or suture tape to increase graft stability. Additionally, 2 studies examined both graft configuration and supplementary fixation.4,12 The key findings from the included studies are summarized in Table 1, which outlines the primary area of focus for each study (whether it was graft configuration, supplementary fixation, or both).
There was also a range of specimen numbers, group comparisons, and testing protocols to evaluate the biomechanical properties of all‐inside ACL grafts in our study. The number of specimens used in the studies varied significantly, reflecting the diversity in experimental designs. The minimum number of specimens was 15, as reported by Graf-Alexiou et al 9 in which there were 3 groups of 5 porcine tendons each. The 3 groups had different configurations: unsecured fixation, secured end‐to‐end fixation, and side‐to‐side with backup fixation. 9 In contrast, the maximum number of specimens was 60, as reported by Richardson et al 18 in which 6 different graft preparation techniques using bovine tendons were evaluated. Most studies used between 20 and 25 specimens, which were divided into groups of 5 to 8.
Stiffness values varied widely across studies, reflecting differences in graft configurations and fixation methods.4,9,10,12,20,21,24 The minimum stiffness reported was 132 N/mm, observed in the control group by Wicks et al, 21 whereas the maximum stiffness of 1086.2 N/mm was reported in the Quad-A group by Wichern et al. 20 Quadruple-folded grafts consistently demonstrated higher stiffness compared with triple‐folded grafts. The ultimate load‐to‐failure values also varied significantly, with the minimum load to failure reported as 300 N in Wichern et al 20 using alternative graft preparation techniques and the maximum load to failure exceeding 1000 N in Bachmaier et al 2 for the suture‐locking device (SLD) and dual‐locking device (DLD) groups. Detailed biomechanical outcomes, including stiffness and ultimate load to failure, are presented in Table 2 for all 11 studies.
Table 2.
Biomechanical Outcomes a
| First Author (Year) | No. of Specimens | Stiffness, N/mm | Ultimate Load to Failure, N |
|---|---|---|---|
| Bachmaier 2 (2023) | 24 (3 groups of 8) | No significant difference between constructs | BLD: 865.0 ± 183.8 SLD and DLD: >1000 |
| Barrera 3 (2019) | 16 (8 matched pairs) | Not mentioned | Supplemented: 797.5 ± 49.6 Control: 719.6 ± 69.6 |
| Bowes 4 (2020) | 25 (5 groups of 5) | Graft A: 167 ± 12 Graft B: 187 Graft C: 212 ± 10 Graft D: 192 Graft E: 198 |
Graft A: 637 ± 99 Graft B: 749 Graft C: 846 ± 26 Graft D: 829 Graft E: 828 |
| Graf-Alexiou 9 (2021) | 15 (3 groups of 5) | Graft A: 166 ± 12 Graft C: 212 Graft M: 215 ± 8 |
Graft A: 637 ± 99 Graft C: 846 Graft M: 883 ± 66 |
| Liu 10 (2025) | 20 (4 groups of 5) | New S-S: 236.85 ± 9.73 Kessler: 188.50 ± 199.40 Krackow: 206.37 ± 11.57 Whipstitch: 206.6 ± 5.85 |
New S-S: 931.03 ± 20.53 Kessler: 806.19 ± 16.84 Krackow: 838.2 ± 36.69 Whipstitch: 907.63 ± 27 |
| Mayr 12 (2016) | 24 (3 groups of 8) | Hybrid: 215.7 2-suture: 213 4-suture: 203.4 |
Hybrid: 801 ± 107 2-suture: 699 ± 87 4-suture: 766 ± 70 |
| Richardson 18 (2019) | 60 (6 groups of 10) | Not mentioned | Traditional: 778 ± 176 6-strand: 491 ± 186 Button: 326 ± 27 |
| Tiefenboeck 19 (2019) | 24 | Not mentioned | Buried knot: 848 Continuous loop: 731 |
| Wichern 20 (2018) | 50 (5 groups of 10) | Quad-A: 1086.2 Quad-B: 460.4 Alternatives: 210-385 |
Quad-A: 641.2 Quad-B: 405.9 Alternatives: 73.3 – 143.4 |
| Wicks 21 (2022) | 20 | Reinforced: 136 Control: 132 |
Reinforced: 921 ± 180 Control: 717 ± 122 |
| Yoo 24 (2019) | 24 (3 groups of 8) | 2-RS suture: 247.28 ± 53.39 4-RS suture: 329.27 ± 55.56 |
2-RS suture: 567.74 ± 60.50 4-RS suture: 736.46 ± 32.50 |
Data are shown as mean or mean ± SD. BLD, button‐locking device; DLD, dual‐locking device; RS, rip-stop; SLD, suture‐locking device; S-S, side‐to‐side.
The diversity in testing protocols further contributed to the heterogeneity in biomechanical outcomes observed across studies. For example, Bachmaier et al 2 performed progressive cyclic loading from 50 to 300 N for 3000 cycles, with a pull‐to‐failure rate of 50 mm/min, whereas Bowes et al 4 performed progressive cyclic loading from 50 to 250 N for 500 cycles, with a pull‐to‐failure rate of 20 mm/min. These differences highlight the challenges in making direct comparisons across studies and further justify the use of a qualitative synthesis rather than a pooled statistical analysis. A summary of the testing protocols is provided in Table 3.
Discussion
The major findings of this review demonstrated that graft configuration and fixation method have important bearings on graft strength and stability and affect clinical outcomes in all‐inside ACL reconstruction. The permutations of these critical factors are tested during surgery such as limited tendon length and minimal fixation or cerclage to reduce foreign material and the infection risk. The laboratory setting offers the exceptional advantage of the permutations of these factors and objectively subjecting the graft and fixation constructs to simulation to assess the strength and stability of both the graft and fixation method on day zero of surgery.
Graft configuration is the cornerstone of all‐inside ACL reconstruction, with studies demonstrating significant variations in biomechanical performance on the basis of different graft configurations, as demonstrated in Table 2. The number of strands per graft, suturing technique, and fixation method of the free ends of the graft are critical factors that influence the mechanical properties of the graft, alongside graft length and diameter.
The quadruple‐folded graft consistently demonstrated superior stiffness and load‐to‐failure values across the 11 studies included in this review. Wichern et al 20 compared quadruple‐folded grafts (Quad-A) with triple‐folded grafts and reported that the former achieved more than 2.5 times greater stiffness (1086.2 N/mm) and more than 8 times greater ultimate load to failure (641.2 N) compared with the latter (385.4 N/mm and 73.3 N) respectively. This finding is consistent with clinical evidence showing that 4‐stranded grafts are associated with reduced failure rates. 18
However, the length of the semitendinosus tendon can vary significantly based on patient characteristics, such as height, weight, and ethnicity. For example, a Chinese population has been reported to have shorter hamstring tendons (26.1 cm) than a White population (28.9 cm).5,17 When the harvested tendon is too short or narrow to obtain a 4‐stranded graft, an alternative graft configuration is required to achieve similar graft strength. Richardson et al 18 evaluated 6 alternative graft constructs but reported that only 3 configurations, the anastomosis 4‐stranded (699.9 N), 3‐stranded (576 N), and loop‐and‐tack 4‐stranded (769.7 N) grafts, produced statistically comparable ultimate load‐to‐failure values, which were comparable with those of traditional 4‐stranded grafts (778 N). Yoo et al 24 evaluated 3‐stranded grafts using 2 different suturing techniques, with 4 rip‐stop sutures resulting in the highest stiffness (329.3 N/mm) and ultimate load to failure (736.5 N) compared with 2 rip‐stop sutures (247.3 N/mm and 567.7 N, respectively). Hence, a quadruple‐folded graft configuration is preferred for its superior ultimate load‐to‐failure values ranging from 700 to 1000 N. Although this range is lower than the native ACL's mean tensile strength of 2160 N,2,3,21,23 the native ACL is usually subjected to forces between 156 and 170 N during daily activities, which increase to 448 N when moving down stairs and up to 700 N if a person stumbles. 19
Suturing techniques play a critical role in optimizing mechanical properties of the graft construct. Mayr et al 12 compared hybrid fixation methods and reported that 4‐suture constructs achieved higher ultimate load to failure (766 N) compared with 2‐suture constructs (699 N), demonstrating that additional sutures can significantly enhance graft stability. However, excessive suture material may increase the risk of infections near the knee joint.1,19,22 Tiefenboeck et al 19 introduced the buried knot technique, which provides superior graft link stability compared with continuous‐loop fixation. Grafts prepared with the buried knot technique achieved an ultimate load to failure of 848 N compared with 731 N for the continuous‐loop construct. The use of buried knots or rip‐stop sutures minimizes elongation and improves resistance to cyclic loading, increasing the strength of the graft closer to that of the native ACL.19,24
Securing the free ends of a graft significantly increases the stability of the graft. The free ends of a graft can be left unsecured or stitched (ie, end‐to‐end or side‐to‐side configuration). Graf-Alexiou et al 9 reported that unsecured fixation of the free ends of the graft was inferior in ultimate load to failure (637 N) and stiffness (166 N/mm) compared with grafts with side‐to‐side (883 N and 215 N/mm, respectively) or end‐to‐end (846 N and 212 N/mm, respectively) fixation. 10 This finding is echoed by Bowes et al, 4 who reported that unsecured fixation had the lowest ultimate load to failure and stiffness and the highest elongation rate. However, Bowes et al 4 reported that grafts with secured side‐to‐side fixation had a lower ultimate load to failure (749 N) compared with grafts with secured end‐to‐end fixation (846 N), with no statistically significant difference in stiffness. Importantly, there was no longer any statistically significant difference in ultimate load to failure between side‐to‐side (829 N) and end‐to‐end (828 N) grafts when secondary fixation was performed by tying accessory sutures to the tibial button. 4 Liu et al 10 compared different suturing techniques for the free ends of 4‐stranded grafts and reported that their new side‐to‐side technique achieved the highest stiffness (236.9 N/mm) and ultimate load to failure (931.0 N), outperforming the end‐to‐end Krackow (838.2 N) and whipstitch (907.6 N) techniques.
The ideal graft requires a sufficient diameter for strength and an adequate length for proper fixation and bone integration. Grafts with diameters ≥8 mm are generally preferred, as smaller diameters have been associated with higher failure rates in clinical settings. 3 These findings align with clinical evidence suggesting that larger graft diameters are associated with improved knee joint stability and reduced revision rates. 17 In 6 studies, grafts with diameters >10 mm were used.3,4,9,10,20,21 However, such data need to be interpreted carefully before their application in clinical practice. A graft diameter of 8 to 10 mm is usually practical, and a larger graft diameter can cause notch impingement and overstuffing, leading to compromised knee function and increased revision rates. 16
Most studies in this review utilized grafts with lengths of 60 to 70 mm, which are sufficient for secure fixation with suspensory devices.2,12,18,19,20,24 Shorter grafts may compromise fixation strength and increase the risk of graft slippage or elongation, particularly under cyclic loading. Conversely, excessively long grafts may complicate surgical handling and tensioning.
The all‐inside ACL technique uses adjustable‐loop devices as primary fixation for graft tensioning and as dual suspensory fixation. 6 It reduces overall construct displacement in comparison with fixed‐loop devices3,13,14 when retensioning of the graft after knee cycling and tibial fixation is achieved. 8 Bachmaier et al 2 compared the stabilization behavior of 3 adjustable‐loop suspensory devices (SLD, button‐locking device [BLD], and DLD). While all the devices exhibited minimal loop elongation under cyclic loading, the DLD restricted dynamic elongation to <3 mm, making it the most stable option. The ultimate load to failure for the BLD was 865.0 N, whereas the SLD and DLD both exceeded 1000 N, indicating robust fixation. These findings suggest that the DLD is the most suitable suspensory device for the all‐inside ACL graft technique. Although it has also been reported that adjustable‐loop devices may loosen when they are not tied off after retightening, the loosening can be overcome by retensioning the graft and knot tying.8,15 This reduces the concern of graft elongation during rehabilitation.
Supplementary fixation, such as with suture anchors and suture tape, reduces cyclic displacement and enhances graft stability. 3 Barrera et al 3 demonstrated that supplementary fixation of inner limbs in a quadrupled graft construct increased the ultimate load to failure from 719.6 N (control) to 797.5 N (supplemented). This was accomplished by tying the sutures from the inner‐limb whipstitch over the tibial suspensory fixation button using alternating half‐hitches. 3 Similar supplementary fixation was reported by Bowes et al 4 and was shown to improve graft strength. Wicks et al 21 evaluated the use of suture tape as internal bracing in a quadrupled graft and reported that the reinforced graft construct achieved an ultimate load to failure of 921 N compared with 717 N for a nonreinforced graft. The reinforced graft construct also exhibited greater stiffness (136 vs 132 N/mm), further supporting the use of suture tape in soft tissue allografts. 21 Mayr et al 12 reported that the addition of a suspension suture on the tibial cortical button in a graft with only 2 sutures on the tibial graft end (hybrid technique) resulted in comparable ultimate load‐to‐failure (801 N) and stiffness (215.7 N/mm) values with a 4‐suture graft (2 sutures at each end; 766 N and 203.4 N/mm, respectively).
The mode of failure varied according to the graft configuration, suturing technique, and fixation method. The common failure modes were broadly divided into suture failure, graft failure, and fixation failure. Suture failure occurred when the stitching securing the tendons in a graft failed under tension during cyclic loading. Suture failure advocates for the need for reinforced techniques such as the buried knot technique seen in the study by Tiefenboeck et al, 19 which reported knot slippage in continuous‐loop constructs (731 N) versus buried knots (848 N), or the new side‐to‐side technique reported in the study by Liu et al 10 (931.0 N). Graft failure manifested differently across models, with Yoo et al 24 noting tendon slippage in bovine specimens (567.7-736.5 N depending on the suturing technique) and Richardson et al 18 observing graft elongation in various preparations (326-778 N). Fixation failure referred to instances in which the adjustable‐loop devices gave way under loading, such as loop elongation, button slippage, or cortical bone breakout. In Bachmaier et al, 2 button subsidence was noted in SLDs (4/8 specimens), despite a high load to failure (>1000 N), while Mayr et al 12 reported cortical button pullout in 2‐suture constructs (699 N) and 4‐suture constructs (766 N) versus rupturing of the femoral cortical button loop for the hybrid technique (801 N). Fixation failure underscores the need for adjustable‐loop device optimization and the consideration of hybrid fixation methods. These findings highlight the critical role of suturing technique and supplementary fixation in preventing graft failure and ensuring long‐term graft stability.
The limitations in the current review included heterogeneity in graft types, graft sizes, fixation methods, and testing protocols. This precluded a meta‐analysis, and hence, a qualitative comparison between the studies was performed instead in this review. The differing use of bovine, porcine, and cadaveric specimens introduces variability in biomechanical outcomes because of the native difference in material composition and as the in vitro environment cannot fully replicate in vivo conditions. The heterogeneous selection of testing protocols, as seen in Table 3, limits comparisons across studies and challenges the interpretation of results.
In summary, graft strength and stability in all‐inside ACL reconstruction are enhanced by optimizing graft configuration, suturing technique, and supplementary fixation, alongside appropriate adjustable‐loop device use as primary fixation.2,3,21 Hence, despite inherent heterogeneity across studies, this review provides a novel decision‐making framework for surgeons navigating graft selection and fixation in all‐inside ACL reconstruction. Future research should focus on prospective clinical trials evaluating the long‐term outcomes of various graft configurations and fixation methods identified in laboratory settings, particularly in patient populations with limited graft resources.
Conclusion
Our review demonstrated that a quadruple‐folded graft with the side‐to‐side suturing technique, suspended by 2 adjustable‐loop devices with additional tensioning and knot tying, and supplementary fixation with tibial reinforcement appears to offer the most stability. This information is clinically relevant to the surgeon in decision making when faced with challenges such as limited graft material to importantly tailor the application to the needs of the patient. This has the potential to optimize functional recovery after ACL reconstruction via improved graft stability and reduced rerupture rates.
Appendix
Table A1.
Summary of Graft Configurations a
| First Author (Year) | Type of Study | Type of Specimen | No. of Specimens | No. of Cerclage Sutures Used | Graft Configuration and Fixation Method | Graft Length and Diameter |
|---|---|---|---|---|---|---|
| Bachmaier 2 (2023) | Controlled laboratory study | Bovine (tendons), porcine (tibias) | 24 (3 groups of 8) | Not specified | Quadrupled graft Femoral fixation: SLD, BLD, DLD Tibial fixation: suture-locking |
Length: 70 mm Diameter: 9 mm |
| Barrera 3 (2019) | Controlled laboratory study | Human cadaveric | 16 (8 matched pairs) | 2 per end | Supplemented group: sutures from inner limb whipstitched to tibial suspensory button using alternating half-hitches Control group: no additional stitching |
Length: 78.1 ± 5.0 mm in supplemented, 78.1 ± 5.2 mm in control Diameter: 11.25 ± 0.8 mm |
| Bowes 4 (2020) | Controlled laboratory study | Porcine (flexor tendons) | 25 (5 groups of 5) | Not specified | Graft A: unsecured fixation Graft B: secured side‐to‐side fixation Graft C: end‐to‐end fixation Grafts D and E: same as B and C but suture ends passed through tibial buttons and tied |
Length: 50 mm Diameter: 12 mm |
| Graf-Alexiou 9 (2021) | Controlled laboratory study | Porcine (flexor tendons) | 15 (3 groups of 5) | Not specified | Graft A: unsecured fixation Graft C: secured end‐to‐end fixation Graft M: side‐to‐side with backup fixation |
Length: 50 mm Diameter: 12 mm |
| Liu 10 (2025) | Controlled laboratory study | Porcine (extensor tendons) | 20 (4 groups of 5) | Not specified | New S-S (side-to-side), whipstitch (side-to-side), Krackow (end-to-end), and Kessler (end-to-end) | Length: not explicitly mentioned Diameter: 50 mm |
| Mayr 12 (2016) | Controlled laboratory study | Bovine | 24 (3 groups of 8) | 2 (hybrid, 2-suture), 4 (4-suture) | 4 buried knot sutures, 2 sutures on tibial end only, and 2 sutures on tibial graft end with additional suspension on tibial cortical button | Length (folded): 65 mm Diameter: 9 mm |
| Richardson 18 (2019) | Controlled laboratory study | Bovine | 60 (6 groups of 10) | 2 per end for most constructs | Traditional 4‐stranded, anastomosis 4‐stranded, 6-stranded, 3‐stranded, button‐fixation 4‐stranded, and loop‐and‐tack 4‐stranded grafts | Length: 70 mm Diameter: 9 mm |
| Tiefenboeck 19 (2019) | Controlled laboratory study | Human cadaveric | 24 | 4 total (2 at each end) | Quadrupled graft with 2 different configurations: buried knot vs continuous loop | Length: 67.5 ± 10 mm Diameter: 8 ± 1.5 mm |
| Wichern 20 (2018) | Controlled laboratory study | Porcine | 50 (5 groups of 10) | 4 total (2 at each end) | 2 quadrupled (Quad-A, Quad-B) and 3 alternative methods (tripled, folded, 2-doubled) | Length: 52.5 ± 1.9 mm to 68.9 ± 1.0 mm Diameter: 12.6 ± 0.4 mm to 17.8 ± 0.7 mm |
| Wicks 21 (2022) | Controlled laboratory study | Porcine | 20 | 4 total (2 at each end) | Quadrupled, another with suture tape placed through tension loop in femoral fixation construct | Length: not specified Diameter: 10, 10.5, and 11 mm |
| Yoo 24 (2019) | Controlled laboratory study | Bovine | 24 (3 groups of 8) | Not specified | Triple-stranded graft prepared with buried knot with 4 sutures, 2 RS sutures, and 4 RS sutures | Length (tripled): 70 mm Diameter: 8 mm |
Data are shown as mean or mean ± SD. BLD, button‐locking device; DLD, dual‐locking device; RS, rip-stop; SLD, suture‐locking device; S-S, side‐to‐side.
Footnotes
Final revision submitted May 18, 2025; accepted June 27, 2025.
The authors have declared that there are no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
Ethical approval was not sought for the present study.
ORCID iD: Amirzeb Aurangzeb 
https://orcid.org/0000-0002-3536-9145
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