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 Table of Contents  
ORIGINAL ARTICLE
Year : 2022  |  Volume : 5  |  Issue : 2  |  Page : 66-73

Comparison between suspensory and aperture (Tunnel Screws) fixation of femoral component during anterior cruciate ligament reconstruction using hamstring tendons


1 Department of Orthopedic Surgery, Asian Institute of Medical Sciences, Faridabad, Haryana, India
2 Department of Physiology, SKMCH, Muzaffarpur, Bihar, India

Date of Submission30-Dec-2021
Date of Decision28-Jan-2022
Date of Acceptance30-Jan-2022
Date of Web Publication28-May-2022

Correspondence Address:
Sudhanshu Shekhar
403, Jaya Neelam Vihar, IAS Colony, Bailey Road, Patna-801503, Bihar
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jodp.jodp_44_21

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  Abstract 


Introduction: Arthroscopic reconstruction of the anterior cruciate ligament (ACL) using an autogenous quadrupled hamstring graft has been the standard of surgical treatment in ACL-deficient knees, particularly in young athletic individuals. There are two widely used methods for graft fixation, namely aperture fixation and suspensory fixation. Material and Methods: This prospective randomized single blinded clinical study was carried out with enrollment of 70 patients (35 patients in each group) who underwent simple block randomization process. Group 1 has 35 patients treated with suspensory fixation technique and Group 2 has 35 patients treated with aperture fixation technique. Result: It is observed that there is a statistically significant difference between the mode of injury and diagnosis in suspensory method. In the majority of the cases, patients who got injury by road traffic accidents (RTA) was diagnosis by 15 (51.7%) ACL Grade 3 and 3 (60%) ACL Grade 4. It is observed that there is a statistically significant difference between the mode of injury and diagnosis in screw fixation. In the majority of the cases, patients who got injury by RTA was diagnosis by 1 (100%) ACL Grade 2, 15 (51.7%) ACL Grade 3, and 3 (60%) ACL Grade 4. Conclusion: Arthroscopy-assisted ACL reconstruction with quadrupled semitendinosus tendon autograft using endobutton and bioabsorbable interference screw is an excellent treatment option for ACL-deficient knees.

Keywords: Aperture method, bioabsorbable, hamstring graft, randomization, suspensory method


How to cite this article:
Pranjal A, Shekhar S, Sinha AK. Comparison between suspensory and aperture (Tunnel Screws) fixation of femoral component during anterior cruciate ligament reconstruction using hamstring tendons. J Orthop Dis Traumatol 2022;5:66-73

How to cite this URL:
Pranjal A, Shekhar S, Sinha AK. Comparison between suspensory and aperture (Tunnel Screws) fixation of femoral component during anterior cruciate ligament reconstruction using hamstring tendons. J Orthop Dis Traumatol [serial online] 2022 [cited 2022 Jul 3];5:66-73. Available from: https://jodt.org/text.asp?2022/5/2/66/346217




  Introduction Top


Anterior cruciate ligament (ACL) rupture is one of the most common knee ligament injuries. With the rise of participation in sports, the incidence of ACL tears has increased in the general population. ACL tear is frequently associated with a sudden directional or speed change while the foot remains firmly planted, rapid deceleration, jumping, pivoting, and direct impact to the anterior aspect of the tibia.[1] Arthroscopic reconstruction of the ACL using an autogenous quadrupled hamstring graft has been the standard of surgical treatment in ACL-deficient knees, particularly in young athletic individuals. An ideal graft provides low morbidity; excellent cosmesis, strength, stiffness, and stability; secure early fixation; and incorporation near the joint line, thus fulfilling the ultimate goals of ACL reconstruction surgery.[2]

There are two widely used methods for graft fixation namely aperture fixation (fixation of the graft to the bone through the tunnel at the joint level in the intercondylar notch) and suspensory fixation (fixation of graft to bone at lateral cortex of the femur). Aperture fixation has benefits over distal fixation which includes avoidance of suture stretch, graft-tunnel pistoning, and windshield-wipering.[3]

Aim and objective

Aim

To study the clinical outcomes derived from comparison between suspensory and aperture (tunnel screws) fixation of femoral component during ACL reconstruction using hamstring tendons in patients at the Department of Orthopedic Surgery, Asian Institute of Medical Sciences, Faridabad, for 2 years.

Primary objective

  1. To assess clinical outcomes in patients undergoing two different technique of ACL reconstruction using Lachman test, anterior drawer test, visual analog scale (VAS) pain score, and Lysholm knee scoring.


Secondary objectives

  1. To record and compare the complications associated with aperture and suspensory fixation of femoral side component of graft in ACL reconstruction using a hamstring tendon autograft [Figure 1], [Figure 2], [Figure 3], [Figure 4]
  2. To evaluate the improvement in knee function and mobility at 2nd, 6th, and 12th weeks after the surgery.
Figure 1: Screw for femur fixation shown

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Figure 2: Screw for femur fixation with driver shown

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Figure 3: Suspensory loop shown

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Figure 4: Suspensory loop with hamstring graft shown

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  Material and Methods Top


The present study was conducted at orthopedic department of our institute between August 2019 and June 2021. The study was approved by the ethical committee of our institute and written consent was taken from the patient. This prospective randomized single-blinded clinical study was carried out with enrollment of 70 patients (35 patients in each group) who underwent simple block randomization process. Group 1 has 35 patients treated with suspensory fixation technique and Group 2 has 35 patients treated with aperture fixation technique.

Inclusion criteria

  1. Age >18 years
  2. Patients giving informed consent to undergo the study
  3. Clinical and radiological evidence of ACL tear
  4. Patients with associated meniscal and chondral pathology (except those meeting the exclusion criteria listed below).


Exclusion criteria

  1. Patients with bony avulsions of ACL
  2. ACL tear with unstable other ligament injury like medial collateral ligament, posterior cruciate ligament, or lateral collateral ligament
  3. Any history of previous knee surgery
  4. Patients with previous ACL reconstructive surgery
  5. Patients with stiff knee/osteoarthritis of knee
  6. Pregnant patients.


Intervention

Suspensory or aperture fixation of the femoral component of graft in ACL reconstruction using a hamstring tendon autograft.

  • Anteroposterior, lateral radiographs, and magnetic resonance imaging scan of the knee were done for each patient
  • Joint laxity and level of disability were recorded as per Lysholm score
  • All routine investigations for the purpose of preanesthetic checkup were done
  • Immediately postoperative patients were put on knee brace and rehabilitation.


Protocol was followed. Full weight-bearing with brace support was encouraged as soon as possible.

  • Postoperatively, routine analgesics and antibiotics were given
  • Digital AP and lateral radiographs of knee in full extension were done in postoperative period [Figure 5], [Figure 6], [Figure 7], [Figure 8]. In the radiographs, the tunnel was assessed in frontal and sagittal plane for tunnel position and inclination
  • Physiotherapy was done as per the standard protocol.
Figure 5: Post op xray of suspensory femur fixation in ACL reconstruction (AP)

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Figure 6: Post op xray of suspensory femur fixation in ACL reconstruction(Lateral)

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Figure 7: Post op xray of screw femur fixation in ACL reconstruction (AP)

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Figure 8: Post op xray of screw femur fixation in ACL reconstruction(Lateral)

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Postoperatively, patients were followed weekly in 1st month and there after every fortnight till 3 months. However, the detailed Lysholm's knee scoring (Lachman and anterior drawer test were quantified using a rolimeter) and proprioceptive function tests (motion and position sense) were recorded at 4th, 6th, and 12th weeks for the functional outcome.

Outcome variable

Primary

  • To evaluate the improvement in knee function and mobility at 2nd, 6th, and 12th weeks after the surgery.


Secondary

  • Proportion of patients with pain and discomfort after surgery (VAS score)
  • Proportion of patients developing complications after surgery.



  Observations and Results Top


The age group in the present study was between 19 and 58 years. A statistically significant difference was not observed between suspensory method and screw fixation in the age group distribution. However, maximum patients were distributed in the age Group 21–30 with 36 (51.4%) and 31–40 with 20 (28.6%) in total as shown in [Table 1]. Minimum age was 19 years and maximum 58 years with mean 29.87 years with standard deviation 8.27.
Table 1: Distribution of study subjects as per age

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[Table 2] shows distribution of studies as per sex in suspensory method and screw fixation group. [Table 2] shows as the males with maximum of 29 (74.3%) males in suspensory method group to 29 (74.3%) males in screw fixation method group. Whereas 9 (25.7%) and 7 (20%) females were there in screw fixation and suspensory method group. On applying Chi-square test, we found no significant difference with P = 0.56
Table 2: Distribution of subjects as per sex

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In [Table 3], the distribution of diagnosis in suspensory method and screw fixation was not significant statistically, but majority of patients were diagnosed with ACL Grade 3 in both 29 (82.9%) suspensory and 26 (74.3%) screw fixation method and minimum patients were diagnosed with ACL Grade 2 in both suspensory and screw fixation method.
Table 3: Distribution according to diagnosis

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In [Table 4], the distribution of mode of injury in suspensory method and screw fixation was not significant statistically, but majority of patients got injury from road traffic accidents (RTA) in both 19 (54.3%) suspensory and 16 (45.7%) screw fixation method and minimum 1 (1.4%) patient got injury after fall from height in total.
Table 4: Distribution according to mode of injury

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In [Table 5], it is observed that there was a statistically significant difference between the mode of injury and diagnosis in suspensory method. In the majority of the cases, patients who got injury by RTA were diagnosed with 11(42.3%) ACL Grade 3 and 4(50%) ACL Grade 4.
Table 5: Distribution of mode of injury and diagnosis in suspensory method

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In [Table 6], it is observed that there is a statistically significant difference between the mode of injury and diagnosis in screw fixation. In the majority of the cases, patients who got injury by RTA were diagnosed with 1 (100%) ACL Grade 2, 15 (51.7%) ACL Grade 3 and 3 (60%) ACL Grade 4.
Table 6: Distribution of mode of injury and diagnosis in screw fixation

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In [Table 7], the distribution of associated injury in suspensory method and screw fixation was not significant statistically, but majority of patients got injury from RTA in both 19 (54.3%) suspensory and 16 (45.7%) screw fixation method and minimum 1 (1.4%) patient got injury after fall from height in total.
Table 7: Distribution according to associated injury

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In [Table 8], the distribution of associated injury and diagnosis in suspensory method and screw fixation group was not significant statistically, but majority of 24 (100%) patients who were diagnosed with ACL Grade 3 did not had associated injury and minimum 1 (25%) patients who were diagnosed with ACL Grade 2 had medical meniscal injury.
Table 8: Distribution according to associated injury and diagnosis in suspensory method

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In [Table 9], the distribution of associated injury and diagnosis in suspensory method and screw fixation group was not significant statistically, but majority of 21 (91.3%) patients who were diagnosed with ACL Grade 3 did not had associated injury and minimum 1 (25%) patients who were diagnosed with ACL Grade 2 had medical meniscal injury.
Table 9: Distribution according to associated injury and diagnosis in screw fixation

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When compared before surgery pain, VAS pain score was decreased significantly after 12 weeks of surgery (P 0.001) in suspensory method group and screw fixation method group [Table 10].
Table 10: Comparison of variables before and after surgery

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When compared before surgery pain, Lysholm knee score was increased significantly after 12 weeks of surgery (P = 0.001) in suspensory method group and screw fixation method [Table 10].

In [Table 11], the distribution of return to normal lifestyle in suspensory method and screw fixation was not significant statistically, but majority of patients returned to normal lifestyle. Thirty-four out of 35 return to normal lifestyle, whereas only 33 out of 35 had returned to normal lifestyle in screw methods.
Table 11: Distribution according to return to normal lifestyle

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In [Table 12], the distribution of complications in suspensory method and screw fixation was not significant statistically, but majority of patients did not have any complications after recovery in both 24 (68.6%) suspensory and 25 (71.4%) screw fixation method.
Table 12: Distribution according to complications

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  Discussion Top


Age

The age group in the present study was between 19 and 58 years. A statistically significant difference was not observed between suspensory method and screw fixation in the age group distribution. However, maximum patients were distributed in the age Group 21–30 with 36 (51.4%) and 31–40 with 20 (28.6%) in total. Minimum age was 19 years and maximum 58 years with mean 29.87 years with standard deviation 8.27. In a study by Dr. Gulia AK et al. (2018), age groups of the studied cases revealed that the most common affected age group was between 18 and 24 years (34.2%), followed by 32–38 years (31.7%) and 25–31 years (20.8%).[4]

Gender

In the present study, the males with maximum of 28 (80%) were suspensory method and 26( 74.3%) males were in screw fixation method group. Whereas, 9 (25.7%) and 7 (20%) females were there in screw fixation and suspensory method group. Results in accordance with the present study were seen in a study by Khorsheed et al.; all were men (100%).[5] 57% were men in a study by Andreas Persson et al. (2018).[6] There were 9 male and 13 female patients in a study by Porter and Shadbolt.[7]

Diagnosis

In the present study, the distribution of diagnosis in suspensory method and screw fixation was not significant statistically, but majority of patients were diagnosed with ACL Grade 3 in both 29 (82.9%) suspensory and 26 (74.3%) screw fixation method and minimum patients were diagnosed with ACL Grade 2 in both suspensory and screw fixation method. In a study by Kashid MR et al. (2017), 50 cases underwent arthroscopy based on clinical examination and diagnosed as pure ACL. However, during routine diagnostic arthroscopy before ACL reconstruction, many cases were detected with associated meniscal injuries. 68% (17 out of 25 cases) suspensory group and 56% (14 out of 25 cases) aperture group were detected with pure ACL tear. 32% cases of suspensory group and 44% cases of aperture group were detected with medial, lateral, or combined meniscal injuries.[8]

Mode of injury

The distribution of mode of injury in suspensory method and screw fixation was not significant statistically in the present study, but majority of patients got injury from RTA in both 19 (54.3%) suspensory and 16 (45.7%) screw fixation method and minimum 1 (1.4%) patient got injury after fall from height in total. In a study by Dr. Anil Kumar et al. (2018), they had 79 (65.8%) patients due to sports/BPET (Battle Physical Efficiency Test) injuries as the most common mode of injury, 26 (16.7%) patients due to RTA, 15 (12.5%) patients due to fall from height, and in 6 (5%) patients mode of injury was household injuries.[4] In a study by Kashid MR et al. (2017), the most common mode of injury was sports injury (football, basketball, and volley ball game). The second most common mode of injury was during military training.[8]

Associated injury

In the present study, 20% of patients experienced lateral meniscal injury in the suspensory group and 22.9% in aperture group. Equal number of patients had medial meniscal injury in both suspensory group and aperture group. Maximum number of patients in the present study were seen with no associated injury. In a study by Kumar et al., 16 patients had isolated ACL injury and remaining 14 patients had ACL-associated meniscal injuries (40% of Group 1 and 53.3% of Group 2).[9] Of the 6 patients in Group 1, four patients had medical meniscal tear and the remaining 2 had lateral meniscal tear. And among eight patients in Group 2, three patients had medical meniscal injury, 3 had both medial and lateral meniscal injury, and the remaining 2 had isolated lateral meniscal injury.

Joint laxity

In the present study, in suspensory method group, before surgery, joint laxity were present in all 35 patients and after surgery it were absent in all 35 patients. In screw fixation group, before surgery, joint laxity were present in all 35 patients and after surgery it were absent in all 35 patients. In a study by Kashid MR et al. (2017), patients had Grade 1-Grade 2 ligament laxity and most of them had laxity with firm endpoint.[8] However, two (8%) patients of aperture group and four (16%) patients of suspensory group had laxity with loose endpoint with pivot shift with the P value of 0.384. In a study by Sundararajan SR et al. (2018), laxity score in fixed loop group was 3.13.[10]

Lachman test

In the present study, in suspensory method group, before surgery, all 35 patients were positive and after surgery all 35 patients were negative after surgery. In screw fixation group, before surgery, all 35 patients were positive and after surgery all 35 patients were negative after surgery. In a study by Kashid MR et al. (2017), five (20%) patients of aperture group and seven (28%) patients of suspensory group had Lachman test positive with a P value of 0.508.[8]

Ant drawer test

In the present study, in suspensory method group, before surgery, all 35 patients were positive and after surgery all 35 patients were negative after surgery. In screw fixation group, before surgery, all 35 patients were positive and after surgery all 35 patients were negative after surgery. In a study by Kashid MR et al.(2017) Out of 50 patients operated, five (20%) patients of aperture group and six (24%) patients of suspensory group had anterior drawer test positive with P value of 0.733.[8]

Motion sense

In suspensory method group, before surgery, motion sense was absent in all 35 patients. And after surgery, motion sense was present in all 35 patients. In screw fixation group, before surgery, motion sense was absent in all 35 patients. And after surgery, motion sense was present in all 35 patients. In a study by Kashid MR et al. (2017), two patients in aperture group and three patients in suspensory group have to take support of walking aid 12 months after surgery.[8] Three patients each in aperture and suspensory group returned to preinjury status 12 months after surgery. There was no significant difference with respect to postoperative knee pain or pain at follow-up and of usage of walking aids in both the groups.

Visual analog scale pain score

In the present study, when compared before surgery pain, VAS pain score was decreased significantly after 12 weeks of surgery (P = 0.001) in suspensory method group as well as screw fixation group. There were no differences between the 2 groups with respect to the VAS score (P = 0.683) in a study by Yari SS et al.(2020) which at the first postoperative visit (typically 2 weeks after surgery), the VAS scores were higher in the aperture fixation group than in the suspensory fixation group (P = 0.025).[11]

Lysholm score in suspensory method group

In the present study, Lysholm knee score was increased significantly after 12 weeks of surgery (P = 0.001) in the suspensory method group. In a study by Kashid MR et al. (2017) preoperative Lysholm score in suspensory group was 46.16 ± 4.60 and improved significantly after surgery.[8] Khorsheed LJ et al. (2019)[12] also presented similar findings.

Lysholm score in screw fixation group

When compared before surgery Lysholm knee score was increased significantly after 12 weeks of surgery (P = 0.001) in screw fixation group. In a study by Sundararajan SR et al. (2018), Lysochlm knee score in fixed loop group was 87.29.[10] In a study by Kashid MR et al. (2017), preoperative Lysholm score in aperture group was 45.32 ± 4.75.[8]

Complications

In the present study, the distribution of complications in suspensory method and screw fixation was not significant statistically, but majority of patients did nor have any complications after recovery in both 24 (68.6%) suspensory and 25 (71.4%) screw fixation method. In a study by Dr. Anil Kumar et al. (2018), 9 patients had superficial infection, 6 patients had joint effusion in immediate postoperative period, 9 patients had knee pain, 7 patients had sense of giving away during exertional activities, and 19 patients had thigh muscle wasting (2–3 cm).[4] There were no graft ruptures, persistent anterior knee pain, infection, or deep vein thrombosis/pulmonary embolism in a study by Kumar et al.[9] No complications either intraoperative or late postoperative were seen in a study by Andreas Panagopoulos et al.[13]


  Conclusion Top


Arthroscopy-assisted ACL reconstruction with quadrupled semitendinosus tendon autograft using endobutton and bioabsorbable interference screw is an excellent treatment option for ACL-deficient knees.

When compared before surgery pain, VAS pain score was decreased significantly after 12 weeks of surgery (P = 0.001) in suspensory method group.

When compared before surgery pain, VAS pain score was decreased significantly after 12 weeks of surgery (P = 0.001) in screw fixation group.

When compared before surgery pain, Lysochlm knee score was increased significantly after 12 weeks of surgery (P = 0.001) in suspensory method group.

When compared before surgery pain, Lysochlm knee score was increased significantly after 12 weeks of surgery (P = 0.001) in screw fixation group.

In [Table 11], the distribution of return to normal lifestyle in suspensory method and screw fixation was not significant statistically, but majority of patients had returned to normal lifestyle. 34 out of 35 had returned to normal lifestyle in suspensory method, whereas only 33 out of 35 had returned to normal lifestyle in screw methods.

In [Table 12], the distribution of complications in suspensory method and screw fixation was not significant statistically, but majority of patients did not have any complications after recovery in both 24 (68.6%) suspensory and 25 (71.4%) screw fixation method.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Raines B, Naclerio E, Sherman S. Management of anterior cruciate ligament injury? What's in and what's out? Indian J Orthop 2017;51:563-75.  Back to cited text no. 1
[PUBMED]  [Full text]  
2.
Ranjan R, Kumar R, Singh A. Arthroscopic reconstruction of anterior cruciate Ligament injury with autogenous hamstring graft and functional recovery of the patients. Int J Orthop Sci 2018;4:38-40.  Back to cited text no. 2
    
3.
Elliott MJ, Kurtz CA. Peripheral versus aperture fixation for anterior cruciate ligament reconstruction. Clin Sports Med 2007;26:683-93.  Back to cited text no. 3
    
4.
Gulia AK, Singhal A, Kumar S, Munde SL, Malik JS, Nagender Prasad MD. Functional outcome of arthroscopic single bundle anterior cruciate ligament reconstruction using quadruple hamstring graft fixed with adjustable loop endobutton and biointerference screw at a tertiary rural centre. International Journal of Orthopaedics 2019;5:86-93.  Back to cited text no. 4
    
5.
Khorsheed LJ, Saeed AM, Ali ZS, Jaza A, Salih H. Arthroscopic anterior cruciate ligament reconstruction: Comparison of functional out- come between femoral fixations by suspensory fixation versus aperture fixation introduction. Kurdistan Board Med Spec 2020;6:106-11.  Back to cited text no. 5
    
6.
Persson A, Gifstad T, Lind M, Engebretsen L, Fjeldsgaard K, Drogset JO, et al. Graft fixation influences revision risk after ACL reconstruction with hamstring tendon autografts: A study of 38,666 patients from the Scandinavian knee ligament registries 2004-2011. Acta Orthop 2018;89:204-10.  Back to cited text no. 6
    
7.
Porter MD, Shadbolt B. Femoral aperture fixation improves anterior cruciate ligament graft function when added to cortical suspensory fixation: An in vivo computer navigation study. Orthop J Sports Med 2016;4:232-59.  Back to cited text no. 7
    
8.
Shaktawat DS, Mishra AK, Kashid MR, Chaudhry A, Stanely A. Comparative study between bone patellar tendon bone and quadrupled hamstring autografts in arthroscopic anterior cruciate ligament reconstruction with aperture fixation. Int J Res Orthop 2017;3:185-9.  Back to cited text no. 8
    
9.
Kumar DB, Aravind JD, Hiranya Kumar S. A comparative study of clinical and functional outcome of arthroscopic anterior cruciate ligament reconstruction using hamstring graft with aperture fixation versus suspensory device fixation. Int J Orthop Sci 2021;7:116-24.  Back to cited text no. 9
    
10.
Sundararajan SR, Sambandam B, Singh A, Rajagopalakrishnan R, Rajasekaran S. Does second-generation suspensory implant negate tunnel widening of first-generation implant following anterior cruciate ligament reconstruction? Knee Surg Relat Res 2018;30:341-7.  Back to cited text no. 10
    
11.
Yari SS, El Naga AN, Patel A, Qadeer AA, Shah A. TightRope Versus Biocomposite Interference Screw for Fixation in Allograft ACL Reconstruction: Prospective Evaluation of Osseous Integration and Patient Outcomes. JBJS Open Access 2020;5:57-8.  Back to cited text no. 11
    
12.
Khorsheed LJ, Saeed AM, Ali ZS, Jaza A, Salih H. Arthroscopic anterior cruciate ligament reconstruction: Comparison of functional out- come between femoral fixations by suspensory fixation versus aperture fixation Introduction: Kurdistan Board of Medical Specialties 2020;6:106–11.  Back to cited text no. 12
    
13.
Panagopoulos A, Mylonas D, Kouzelis A, Zampakis P, Kraniotis P, Lakoumentas J, et al. No difference in outcomes between suspensory (fixed-loop cortical button) versus expandable anteromedial femoral fixation in anterior cruciate ligament reconstruction with autologous hamstring tendons: A prospective, randomized, controlled study in male patients. Arthrosc Sports Med Rehabil 2021;3:e1155-63.  Back to cited text no. 13
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9], [Table 10], [Table 11], [Table 12]



 

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