MUSCULOSKELETAL SURGERY La Chirurgia degli Organi di Movimento

Fixation techniques for the Anterior Cruciate Ligament Reconstruction: early follow-upA systematic review of level I and II therapeutic studies

--Manuscript Draft--

Manuscript Number: MUSC-D-14-00061

Full Title: Fixation techniques for the Anterior Cruciate Ligament Reconstruction: early follow-upA systematic review of level I and II therapeutic studies

Article Type: Review

Keywords: Keywords: ACL reconstruction; fixation devices; doubled Semitendinous and Gracilis,Bone Patellar Tendon Bone

Corresponding Author: Andrea SpezialiGemelli's HospitalITALY

Corresponding Author SecondaryInformation:

Corresponding Author's Institution: Gemelli's Hospital

Corresponding Author's SecondaryInstitution:

First Author: Andrea Speziali

First Author Secondary Information:

Order of Authors: Andrea Speziali

Marco Delcogliano

Matteo Maria Tei

Giacomo Placella

Matteo Bartoli

Amerigo Menghi

Giuliano Cerulli

Order of Authors Secondary Information:

Abstract:Purpose: The purpose of our study is that to systematically review the fixationtechniques for the ACL reconstruction and associated clinical outcomes at the earlyfollow-up.

Methods: Systematic search on three electronic databases (Cochrane register,Medline and Embase) of fixation devices used for primary ACL reconstruction withDSTG and BPTB autografts in randomized clinical trials of level I and II of evidencepublished from January 2001 to December 2011.Therapeutic studies collected were with a minimum 12 month follow-up and the clinicaloutcomes were evaluated by at least one of IKDC, Lysholm and Tegner functionalscales and at least one of the following knee stability tests: arthrometric AP tibialtranslation, Lachman test and Pivot-shift test.

Results: Ninenteen articles met the inclusion criteria. At the femoral side cross-pin,metallic interference screw, bioabsorbable interference screw, suspensory device wereused in 32.3%, 27.3%, 24.8%, 15.5% of patients, respectively. At the tibial side fixationwas achieved with metallic interference screw, bioabsorbable interference screw,screw and plastic sheath, screw post and cross-pin in 38.7%, 31%, 15.7 %, 12.8%, and1.7 % of patients, respectively. Side-to-side APTT was 1.9 ± 0.9 mm, 1.5 ± 0.9 mm,1.5 ± 0.8 mm, 2.2 ±.4 mm for metallic interference screw, bioasborbable screw, cross-pin and suspensory device, respectively.

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At least two third of all the patients achieved good to excellent clinical outcomes.Rate of failure was 6.1%, 3.3%, 1.7% and 1.2% for bioabsorbable interference screw,metallic interference screw, cross-pin and suspensory device, respectively.

Conclusion: Clinical outcomes are good to excellent in almost two third of the patientsbut several pitfalls that affect the current fixation techniques as graft tensioning such asgraft-tunnel motion are still unaddressed.

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Fixation techniques for the Anterior Cruciate Ligament Reconstruction: early follow-up 8

A systematic review of level I and II therapeutic studies 9

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Andrea Speziali1 MD, Marco Delcogliano1 MD, Matteo Tei1 MD, Giacomo Placella1MD, Matteo Bartoli 1MD, 11

Amerigo Menghi 1MD, Giuliano Cerulli1,2 MD 12

1Institute of Orthopedic and Traumatology, Catholic University, ‘Agostino Gemelli’ Hospital, Rome, Italy 13

2 Institute Of Translational Research for Musculoskeletal System ‘Nicola Cerulli’, Arezzo, Italy 14

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Corresponding authors: 20

Andrea Speziali MD, Giuliano Cerulli MD 21

Let People Move Research Institute, Arezzo, Italy 22

E-mail: andrea.speziali@gmail.com 23

Phone: +39 0575 1948501 24

Title Page

Abstract 1

Purpose: The purpose of our study is that to systematically review the fixation techniques for the ACL reconstruction 2

and associated clinical outcomes at the early follow-up. 3

Methods: Systematic search on three electronic databases (Cochrane register, Medline and Embase) of fixation devices 4

used for primary ACL reconstruction with DSTG and BPTB autografts in randomized clinical trials of level I and II of 5

evidence published from January 2001 to December 2011. 6

Therapeutic studies collected were with a minimum 12 month follow-up and the clinical outcomes were evaluated by at 7

least one of IKDC, Lysholm and Tegner functional scales and at least one of the following knee stability tests: 8

arthrometric AP tibial translation, Lachman test and Pivot-shift test. 9

Results: Ninenteen articles met the inclusion criteria. At the femoral side cross-pin, metallic interference screw, 10

bioabsorbable interference screw, suspensory device were used in 32.3%, 27.3%, 24.8%, 15.5% of patients, 11

respectively. At the tibial side fixation was achieved with metallic interference screw, bioabsorbable interference screw, 12

screw and plastic sheath, screw post and cross-pin in 38.7%, 31%, 15.7 %, 12.8%, and 1.7 % of patients, respectively. 13

Side-to-side APTT was 1.9 ± 0.9 mm, 1.5 ± 0.9 mm, 1.5 ± 0.8 mm, 2.2 ±.4 mm for metallic interference screw, 14

bioasborbable screw, cross-pin and suspensory device, respectively. 15

At least two third of all the patients achieved good to excellent clinical outcomes. 16

Rate of failure was 6.1%, 3.3%, 1.7% and 1.2% for bioabsorbable interference screw, metallic interference screw, 17

cross-pin and suspensory device, respectively. 18

Conclusion: Clinical outcomes are good to excellent in almost two third of the patients but several pitfalls that affect 19

the current fixation techniques as graft tensioning such as graft-tunnel motion are still unaddressed. 20

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Keywords: ACL reconstruction; fixation devices; doubled Semitendinous and Gracilis, Bone Patellar Tendon Bone 22

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Introduction 24

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Acl reconstruction is one of the most surgical procedure performed by orthopaedic surgeons in the last decade in the 26

sports medicine field. 27

An active debate is focused on the anatomical or non-anatomical placement of the bone tunnels. Woo and collegues [1] 28

had demonstrated as lateral femoral tunnel placement can restore rotatory stability when the knee is near extension, but 29

that is not true at high flexion angles. Fu and collegues [2] reported a preliminary results of the double bundle ACL 30

Manuscript (excluding authors' names and affiliations)

reconstruction. A cochrane systematic review [3] has demonstrated as there is insufficient evidence to determine the 31

relative superiority of the double bundle reconstruction versus single bundle. 32

Second issue is the graft choice. Aglietti and coworkers [4] in a randomized controlled clinical trial had achieved 33

equivalent results between Bone Patellar Tendon Bone (BPTB) and Doubled Semitendinosus and Gracilis (DSTG). 34

However, Cerulli and coworkers[5] in a biomechanical study demonstrated that using a single quadrupled 35

Semitendinosus or Gracilis could restore kinematics of the knee as well as the in situ force in the grafts to the level of 36

the intact ACL. 37

Despite these results, we should consider that each graft has different stiffness and viscoelastic properties [6, 7] and it 38

could require a different graft preconditioning and tensioning during the fixation. 39

Research is challenging towards the development of better surgical techniques and new biomaterials able to achieve 40

optimal long-term outcomes. However, current fixation devices have been unable to reproduce the enthesis of the native 41

ACL and the mechanical properties of the Femur-ACL-Tibia-Complex (FATC)[8]. 42

Several are the objects of the discussion and the fixation device of the graft such as graft tensioning are weak points 43

that need to be addressed. It could impair the outcomes after ACL reconstruction and lead to graft failure cause 44

undertensioning of the graft could lead to residual laxity and overtensioning could overconstraint the knee in extension 45

[9]. Several fixation techniques had introduced for the ACL reconstruction and we could classify it into three main 46

groups : “anatomical or aperture fixation” close to the joint line; “non anatomical or suspensory fixation” and 47

transfixation with cross-pin[10]. 48

Each fixation system has different stiffness [11-14] and mechanical properties and it could manifest as variable post-49

operative laxity of the knee. The tensile properties of the FATC, rather than the strength of the graft, is the weakest link 50

for the stability of the knee after ACL reconstruction, especially in the early rehabilitation. 51

Our purpose is that to achieve a systematic review of the fixation devices applied for the ACL reconstruction in the last 52

years and associated clinical outcomes and post operative complications. 53

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Materials and Methods 55

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Two independent investigators (A.S. and M.T.) made a systematic search of the literature on electronic databases 57

Cochrane controlled trials register, Medline and Embase. 58

Keyterms included anterior cruciate ligament reconstruction, ACL AND fixation devices, ACL AND bone screws, ACL 59

AND interference screws, ACL AND bioabsorbable implants, ACL AND biomaterials. We chose studies able to match 60

the following inclusion criteria:1) randomized controlled therapeutic trials (level of evidence I and II); 2) published 61

from January 1th 2001 to December 31th 2011; 3) articles only in English; 4) at least twelve month follow-up; 5) 62

subjective functional evaluation, at least one of International Knee Documentation Committee (IKDC), Lysholm or 63

Tegner activity scale; 6) population from 13 to 65 years; 7) primary ACL complete injury; 8) ACL replacement with 64

BPTB or DSTG without any limitation of technique; 9) knee stability testing (at least one of the arthrometric side-to-65

side difference, Lachman test, Pivot-shift test); 10) lastly, post-operative complications. 66

Laboratory studies, ex-vivo and animal studies, using allograft, severe osteoarthritis (III-IV sec.Outerbridge), 67

multiligament injuries, retrospective comparison studies (level III), case series (level IV), expert opinion (level V) and 68

revision surgery were considered as exclusion criteria. 69

We established the failure of the ACL reconstruction as > 5 mm at the artrometric side-to-side evaluation, Lachman test 70

≥2 +, Pivot shift test ≥2 + and achievement of a poor functional subjective scale. 71

After identification of the studies data were extracted in four compartiments: population features, fixation techniques; 72

clinical outcomes and post-operative complications. First domain provides a description of the examined population, 73

mean age and range, sex and type of the graft. Second fold points out a brief summary of the reviewed fixation devices. 74

Third domain states the clinical outcomes in three subclasses: knee stability tests which include arthrometric side-to-75

side difference, Lachman test and pivot-shift test; subject functional evaluation which incorporate IKDC score, Tegner 76

activity and Lysholm knee score. Lastly, a fourth domain describes the post-operative complications. 77

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Results 79

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Population features ( Table 1 ) 81

One hundred sixtyone articles met the initial inclusion criteria (Fig.1). After abstract revision one hundred fortyone 82

papers were excluded and the residual twenty underwent to full text revision. Lastly nineteen articles met the inclusion 83

criteria, thirteen were level I of evidence and six of level II. 84

Mean age of the patients was 27.6 ± 2.7 years and overall 1648 ACL reconstructions were screened, 76 % (1253) using 85

DSTG graft and 24 % (395) using BPTB graft. The mean follow-up was 1.8 years and the rate of the patients lost to 86

follow up was 0.8 % (132) (Tab. 1). 87

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Fixation techniques ( Table 2 ) 89

At the femoral side the fixation was achieved using metallic interference screw in 450 patients ( 27.3 % ) , with 90

biorebsorbable interference screw in 409 patients ( 24.8% ), with suspensory device in 256 patients ( 15.5 % ) lastly, 91

using cross-pin in 533 patients ( 32.3 % ) (Tab.2). 92

At the tibial side the fixation was performed using metallic interference screw in 38.7% ( 642 ) of cases, with 93

bioresorbable interference screw in 31% ( 515 ), screw with plastic sheath in 15.7 % ( 260 ), using screw-post cortical 94

device in 12.8% ( 213 ) and using cross-pin in 1.7% ( 28 ) patients. 95

The flexion angle for the final fixation was full extension for 8 authors[4, 15-21], 30° of flexion for 3 authors[22-24], 96

20° of flexion for 1 author[25] and 15° of flexion for 1 author [26]. 97

Graft tensioning was achieved manually in 73.6 % of the ACL reconstructions and using a tensioner only in 26.4% of 98

the patients [16, 22, 27]. 99

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Clinical outcomes ( Table 3 - 4 ) 101

The results of the arthrometric knee evaluation, Lachman test and Pivot-shift test are reported in table 3. Furthermore, a 102

subjective clinical assessment using standardized scales as IKDC, Tegner and Lysholm is reported in Table 4. 103

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Post-operative complications ( Table 5 ) 105

Failure rate, incidence of meniscal tears, breakage and infection for each group are reported in the table 5. 106

Focusing on the femoral side, 28.8 % ( 15 ) of the overall failures happened in the MIS group, 48.1% ( 25 ) in the BIS 107

group, 17.3% ( 9 ) in the cross-pin group, lastly 5.8 % ( 3 ) in the suspensory group. 108

A rate of 37.5% ( 18 ) of the overall meniscal tears were reported in the MIS group, 8.3 % ( 4 ) in the BIS group, 43.7 % 109

( 21 ) in the cross-pin group, 10.4% ( 5 ) in the suspensory group. 110

15.4 % (2) of the overall breakages were reported in the MIS group, 15.4 % ( 2 ) in the BIS group, 38.5 % ( 5 ) in the 111

cross-pin group and 30.7 % ( 4 ) in the suspensory group. 112

Furthermore, 20 % ( 3 ) of the overall infection rate were reported in the MIS group, 53.3 % ( 8 ) in the BIS group, 26.7 113

% ( 4 ) for the suspensory group and none using cross-pin fixation. 114

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Discussion 116

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The DSTG graft is the most common autograft used in the last decade for the ACL reconstruction. Overall, 75.8% of 118

the ACL reconstruction was performed with DSTG and 24.2 % using BPTB. 119

Focusing on post-operative complications overall rate of failure was 3.2 % (52) , overall rate of meniscal tears 2.9% 120

(48) and lastly overall rate of infection 0.8 % (13). 121

In contrast with Colvin and collegues[28], higher rate of failures was seen with bioabsorbable and metallic screw than 122

other devices and it could be attribuited to graft slippage[29] due to weakness of the graft-screw interface in the early 123

stage of osteointegration of the graft [30]. Further, the authors reported that the tendon grafts were damaged by the 124

sharp thread of the metal screw[11, 31]. 125

In addition, one of the reasons could be attribuited to the biological and chemical reactions following the interaction of 126

the tissue with biodegradable materials as poly-L-lactide acid (PLLA), poly-DL-lactide acid (PDLLA) or poly-lactide 127

carbonate (PLC)[32]. 128

Secondly, there was a variability among the tibial fixation[12] and if tibial fixation is stronger than femoral fixation, the 129

femoral implant may become the weak point [33]. 130

However, as suspensory device such as cross-pin fixation don’t exclude graft tunnel motion[34, 35] and this 131

phenomena, known as bungee cord and windshield-wiper effects, could unbalance the healing process of the graft into 132

the bone tunnels especially until the first 6 to 8 weeks [36-40]. 133

Aperture fixation avoids concerns related to the micro-motion of the graft by providing secure fixation close to the joint 134

line [41]. Micro-motion of the graft within the bone tunnel is an element to take care for bone tunnel widening even 135

though no clinical correlation is demonstrated with knee instability yet [32, 42, 43]. Furthemore, biomechanical studies 136

had demonstrated that under cyclic loading suspensory device, cross-pin and interference screw allow for similar 137

amounts of displacement of the graft [11]. Thus, there is no clear biomechanical advantage of one method of fixation in 138

comparison to another. 139

Additionally, no agreement was reported among the flexion angle for the graft fixation and it ranged from 30° to full 140

extension. Biomechanical studies have demonstrated that tensioning at 30° of flexion leads to increased risk of flexion 141

contracture [44] and excessive graft tension in extension [45]. 142

Currently, the graft tensioning cannot be considered as a standard procedure and almost 84 % of the authors tensioned 143

manually the graft and 37% of them did not report how graft tensioning was performed[18, 24, 25, 46-49]. 144

Drogset and collegues [16] tensioned the graft with 4 kg, Harilainen and colleagues [22] performed the graft tensioning 145

with 40 N lastly, Ibrahim et al. [27] used 20 to 30 lb for graft tensioning. 146

Manual graft tensioning includes a wide range of variability that could overconstraint or underconstraint the knee and 147

lead to cartilage degeneration and meniscal tears at long-term follow-up[50, 51]. A popular surgery as ACL 148

reconstruction should include a standardized protocol for graft preconditioning and tensioning and it is still missing. 149

Foldager and colleagues [52] had found that majority of the tunnel expansion takes place during the surgery. Thus, 150

another concern is that there is no control of the real diameter of the bone tunnels after motorized drilling and it could 151

be unmatched as with the caliber of the drill such as with the size of the graft. 152

The instability of the knee was assessed with several arthrometric tools in all the studies but is well known that from a 153

biomechanical perspective the ACL is loaded not only by anterior tibial translation but also by both valgus and internal 154

rotation moments [53]. After ACL reconstruction, a more detailed assessment of the knee stability should include a 155

tridimensional gait analysis during low- and high-demanding tasks to point out the behavior of the knee during motion 156

that stimulates valgus-internal rotational loading [54]. This issue could explain the lower percentage of failure achieved 157

with suspensory devices than aperture fixation. 158

According with a recent meta-analysis of Colvin A et al. [28], all the clinical outcomes in terms of IKDC, Lysholm and 159

Tegner subjective functional scales were satisfactory in almost two third of the patients. 160

The meniscal injuries rate was from 1% to 4 % and could be a consequence of the residual instability of the knee after 161

the ACL reconstruction. 162

Focusing on the breakage of the fixation devices, we have reported an higher percentage of breakage of the suspensory 163

device and the rupture should happen at the continuous loop as biomechanical study had demonstrated [11]. 164

The overall infection rate was from 1.8% to 2.4 % and it was comparable with the results by the recent literature [3, 165

55]. 166

This systematic review has demonstrated that several limitations affect the ACL reconstruction. We believed that ACL 167

reconstruction needs improvement aimed to refine as the surgical procedure and the fixation of the graft such as the 168

post-operative evaluation. Manual graft tensioning is a rough way for loading the neo-ligament and we auspicate new 169

tools able to accomplish an accurate pre-conditioning and tensioning of the graft. 170

Biomechanical studies and randomized clinical trials are encouraged for understanding the role of the graft tensioning 171

and the bone tunnels widening on the stability of the knee. 172

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[33] Monaco E, Labianca L, Speranza A, Agro AM, Camillieri G, D'Arrigo C, et al. Biomechanical evaluation of 291 different anterior cruciate ligament fixation techniques for hamstring graft. Journal of orthopaedic science : 292 official journal of the Japanese Orthopaedic Association 2010;15:125-31. 293 [34] Hoher J, Livesay GA, Ma CB, Withrow JD, Fu FH, Woo SL. Hamstring graft motion in the femoral bone 294 tunnel when using titanium button/polyester tape fixation. Knee surgery, sports traumatology, arthroscopy 295 : official journal of the ESSKA 1999;7:215-9. 296 [35] Choi NH, Son KM, Yoo SY, Victoroff BN. Femoral tunnel widening after hamstring anterior cruciate 297 ligament reconstruction with bioabsorbable transfix. The American journal of sports medicine 2012;40:383-298 7. 299 [36] Clancy WG, Jr., Narechania RG, Rosenberg TD, Gmeiner JG, Wisnefske DD, Lange TA. Anterior and 300 posterior cruciate ligament reconstruction in rhesus monkeys. The Journal of bone and joint surgery 301 American volume 1981;63:1270-84. 302 [37] Weiler A, Hoffmann RF, Sudkamp NP, Siepe CJ, Haas NP. [Replacement of the anterior cruciate 303 ligament. Biomechanical studies for patellar and semitendinosus tendon fixation with a poly(D,L-lactide) 304 interference screw]. Der Unfallchirurg 1999;102:115-23. 305 [38] L'Insalata JC, Klatt B, Fu FH, Harner CD. Tunnel expansion following anterior cruciate ligament 306 reconstruction: a comparison of hamstring and patellar tendon autografts. Knee surgery, sports 307 traumatology, arthroscopy : official journal of the ESSKA 1997;5:234-8. 308 [39] Jorgensen U, Thomsen HS. Behavior of the graft within the bone tunnels following anterior cruciate 309 ligament reconstruction, studied by cinematic magnetic resonance imaging. Knee surgery, sports 310 traumatology, arthroscopy : official journal of the ESSKA 2000;8:32-5. 311 [40] Rodeo SA, Kawamura S, Kim HJ, Dynybil C, Ying L. Tendon healing in a bone tunnel differs at the tunnel 312 entrance versus the tunnel exit: an effect of graft-tunnel motion? The American journal of sports medicine 313 2006;34:1790-800. 314 [41] Brucker PU, Lorenz S, Imhoff AB. Aperture fixation in arthroscopic anterior cruciate ligament double-315 bundle reconstruction. Arthroscopy : the journal of arthroscopic & related surgery : official publication of 316 the Arthroscopy Association of North America and the International Arthroscopy Association 2006;22:1250 317 e1-6. 318 [42] Brand J, Jr., Weiler A, Caborn DN, Brown CH, Jr., Johnson DL. Graft fixation in cruciate ligament 319 reconstruction. The American journal of sports medicine 2000;28:761-74. 320 [43] Kim SJ, Bae JH, Song SH, Lim HC. Bone Tunnel Widening with Autogenous Bone Plugs Versus 321 Bioabsorbable Interference Screws for Secondary Fixation in ACL Reconstruction. The Journal of bone and 322 joint surgery American volume 2013;95:103-8. 323 [44] Austin JC, Phornphutkul C, Wojtys EM. Loss of knee extension after anterior cruciate ligament 324 reconstruction: effects of knee position and graft tensioning. The Journal of bone and joint surgery 325 American volume 2007;89:1565-74. 326 [45] Numazaki H, Tohyama H, Nakano H, Kikuchi S, Yasuda K. The effect of initial graft tension in anterior 327 cruciate ligament reconstruction on the mechanical behaviors of the femur-graft-tibia complex during cyclic 328 loading. The American journal of sports medicine 2002;30:800-5. 329 [46] Kaeding C, Farr J, Kavanaugh T, Pedroza A. A prospective randomized comparison of bioabsorbable and 330 titanium anterior cruciate ligament interference screws. Arthroscopy : the journal of arthroscopic & related 331 surgery : official publication of the Arthroscopy Association of North America and the International 332 Arthroscopy Association 2005;21:147-51. 333 [47] Ma CB, Francis K, Towers J, Irrgang J, Fu FH, Harner CH. Hamstring anterior cruciate ligament 334 reconstruction: a comparison of bioabsorbable interference screw and endobutton-post fixation. 335 Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy 336 Association of North America and the International Arthroscopy Association 2004;20:122-8. 337 [48] Moisala AS, Jarvela T, Paakkala A, Paakkala T, Kannus P, Jarvinen M. Comparison of the bioabsorbable 338 and metal screw fixation after ACL reconstruction with a hamstring autograft in MRI and clinical outcome: a 339 prospective randomized study. Knee surgery, sports traumatology, arthroscopy : official journal of the 340 ESSKA 2008;16:1080-6. 341

[49] Price R, Stoney J, Brown G. Prospective randomized comparison of endobutton versus cross-pin 342 femoral fixation in hamstring anterior cruciate ligament reconstruction with 2-year follow-up. ANZ journal 343 of surgery 2010;80:162-5. 344 [50] Sherman SL, Chalmers PN, Yanke AB, Bush-Joseph CA, Verma NN, Cole BJ, et al. Graft tensioning during 345 knee ligament reconstruction: principles and practice. The Journal of the American Academy of 346 Orthopaedic Surgeons 2012;20:633-45. 347 [51] Fleming BC, Fadale PD, Hulstyn MJ, Shalvoy RM, Oksendahl HL, Badger GJ, et al. The effect of initial 348 graft tension after anterior cruciate ligament reconstruction: a randomized clinical trial with 36-month 349 follow-up. The American journal of sports medicine 2013;41:25-34. 350 [52] Foldager C, Jakobsen BW, Lund B, Christiansen SE, Kashi L, Mikkelsen LR, et al. Tibial tunnel widening 351 after bioresorbable poly-lactide calcium carbonate interference screw usage in ACL reconstruction. Knee 352 surgery, sports traumatology, arthroscopy : official journal of the ESSKA 2010;18:79-84. 353 [53] Georgoulis AD, Ristanis S, Moraiti CO, Paschos N, Zampeli F, Xergia S, et al. ACL injury and 354 reconstruction: Clinical related in vivo biomechanics. Orthopaedics & traumatology, surgery & research : 355 OTSR 2010;96:S119-28. 356 [54] Ristanis S, Giakas G, Papageorgiou CD, Moraiti T, Stergiou N, Georgoulis AD. The effects of anterior 357 cruciate ligament reconstruction on tibial rotation during pivoting after descending stairs. Knee surgery, 358 sports traumatology, arthroscopy : official journal of the ESSKA 2003;11:360-5. 359 [55] Torres-Claramunt R, Pelfort X, Erquicia J, Gil-Gonzalez S, Gelber PE, Puig L, et al. Knee joint infection 360 after ACL reconstruction: prevalence, management and functional outcomes. Knee surgery, sports 361 traumatology, arthroscopy : official journal of the ESSKA 2012. 362

363

364

365

366

367

368 369 370

Fig.1 Flow-diagram of the electronic search performed on the on-line database.

161

articles met initial search

criteria

14 no control group

141 articles did not meet inclusion

criteria: abstract review

23 no stability tests

9 no clinical outcomes

18 case report

10 level of evidence III -IV

48 laboratory studies

14 no control group

11 systematic review

4 meta-analysis

1 multiligamentous injury

1 revision surgery

1 surgical technique

1 press-fit fixation

19

articles met inclusion criteria:

full text review

1

article excluded:

full text review

Figure

Table 1. Population features

Studies LOE Mean age DSTG BPTB Male Female Overall FU LF 1-Aglietti 2004[1] I 25(16-39) 60 60 - - 120 2 -

2-Drogset 2005[2] I 26,5(15-51) - 41 19 22 41 2 3

3-Drogset 2010[3] II 26.5 (18-45) 57 58 73 42 115 2 16

4-Eriksson 2001[4] II 25,7(15-45) 80 84 96 68 164 2.8 4

5-Fauno 2005[5] I 25,5 (NR) 100 - 51 49 100 1 13

6-Harilainen 2009[6] I 31,75(18-50) 120 - 76 44 120 2 10

7-Harilainen 2005[7] I 29,5(15-56) 62 - 42 20 62 2 6

8-Ibrahim 2009[8] I 28 (21-33) 200 - - - 200 2.4 -

9-Jӓrvelӓ 2008[9] I 33 ± 9 77 - 51 26 77 2 4

10-Kaeding 2005[10] II 26,9 (NR) - 97 65 32 97 2 32

11-Laxdal 2006[11] I 26,5(16-46) 77 - 57 20 77 2 9

12-Ma 2004[12] II 24,5(19-35) 30 - 7 23 30 2.9 -

13-Mariani 2001[13] I 24,5(18-42) - 55 40 15 55 2.4 -

14-Moisala 2008[14] II 32 ± 9 62 - 41 21 62 2 7

15-Myers 2008[15] I 30,1(20,7-39,5) 100 - - - 100 2 -

16-Price 2010[16] I 26.4 (16-48) 29 - - - 29 2 5

17-Rose 2006[17] II 27(13-61) 68 - 42 26 68 1 -

18-Stener 2010[18] I 26,5(16-46) 77 - 57 20 77 8 13

19-Stengel 2009[19] I 28,9 (16-63) 54 - 35 19 54 2 10

LOE: level of evidence; DSTG: doubled semitendinosus and gracilis; BPTB: bone-patellar tendon-bone; FU: mean

follow-up (years); LF: lost to follow-up

Table 1

Table.2 Fixation techniques

Author

Femur Tibia

Angle of fixation

Graft

BPTB DSTG BPTB DSTG Tensioning

1-Aglietti 2004[1]

Tunneloc Screw (Arthrotek)

Bone Mulch screw (Arthrotek)

MIS (Smith &Nephew Acufex)

WasherLoc (Arthrotek)

Full extension

manual

2-Drogset 2005[2]

I-BIS II-MIS (Linvatec)

MIS (8-9x25mm)

(Linvatec,Largo,Fla)

Full extension

manual

3-Drogset 2010[3]

MIS (Linvatec,Largo,FL)

Bone Mulch Screw (Biomet,Inc)

MIS (9x25mm) WasherLoc (Arthrotek)

Full extension

4 kg

4-Eriksson 2001[4]

MIS (7x20mm) EB

(Smith&Nephew,Acufex) MIS (9x20mm) MIS

Full extension

manual

5-Fauno 2005[5]

I-Transfix (Arthrex,Naples,FL)

II- EB (Smith&Nephew,Acufex)

I-BIS (Arthrex)

II-screw + spiked washer

NR manual

6-Harilainen 2009[6]

I-Rigidfix II-Rigidfix

III-BIS IV-BIS

I-Intrafix (Mitek) II-BIS

III-Intrafix (Mitek) IV-BIS

30° 40 N

7-Harilainen 2005[7]

I-TransFix (Arthrex) II-MIS

(7-9x20 mm, Linvatec)

I-AO screw+spider washer

II-MIS (Linvatec) 30° manual

8-Ibrahim 2009[8]

I-EB (Smith&Nephew) II-RigidFix (Mitek)

III-TransFix (Arthrex) Intrafix (Mitek) NR 20-30 lb

9-Jӓrvelӓ 2008[9]

I-BIS (SB) II-BIS (DB) III-MIS (SB)

I-BIS (SB) II-BIS (DB) III-MIS (SB)

Full extension

NR

10-Kaeding 2005[10]

I-MIS (7x20mm) II-BIS (7x25mm)

I-MIS (7x20mm) II-BIS (7x25mm)

NR NR

11-Laxdal 2006[11]

I-MIS (Smith&Nephew)

II-BIS (Arthrex)

I-MIS (Smith&Nephew) II-BIS (Arthrex)

Full extension

manual

12-Ma 2004[12]

I-BIS (Linvatec)

II-EB

I-BIS (Linvatec) II-screw post

NR NR

13-Mariani 2001[13]

I-MIS II-TIS (Arthrotek)

I-MIS (Arthrotek)

II-MIS 30° NR

14-Moisala 2008[14]

I- BIS (Hexalon) II- MIS (Timoni)

I- BIS (Hexalon) II- MIS (Timoni)

NA NR

15-Myers 2008[15]

I-MIS(Smith&Nephew) II-BIS (7x25mm, Smith&Nephew)

I-MIS(Smith&Nephew)

II-BIS (7x25mm, Smith&Nephew)

15° manual

16-Price 2010[16]

I-EB

II-TransFix (Arthrex)

I-BIS II-BIS

NA NR

17-Rose 2006[17]

I-TransFix(Arthrex)

II-BIS(Arthrex) BIS (Arthrex)

Full extension

manual

18-Stener 2010[18]

I-MIS (Smith&Nephew)

II-BIS (Arthrex)

I-MIS (Smith&Nephew) II-BIS (Arthrex)

Full extension

manual

19-Stengel 2009[19]

I-RigidiFix BCP

II-BIS

I-RigidiFix BCP II-BIS

20° NR

Fixation techniques: fixation devices, type of graft, flexion angle of fixation and graft tensioning. MIS, metal interference screw; BIS, bioabsorbable interference screw ; EB, endobutton; TIS, transcondylar interference screw; SB, single bundle; DB, double bundle; NR, not reported; I-II-II-IV indicate how the authors had divided the patients in different groups according the fixation of the graft.

Table 2

Table 3. Knee stability tests

APTT MIS[1-10] BIS[1, 4-6, 8-14] CROSS-PIN[3, 7, 11, 13-18]

SUSPENSORY[2, 12, 16-18]

≤ 2 mm 3-5 mm >5 mm

67.4 % (143) 25.9 % (55) 6.6 % (14) 1.9 ±0.9 **

82.8 % (82) 11.1.% (11) 6.1 % (6) 1.5 ±0.9 **

71.9% (207) 21.5% (62) 6.6 % (19) 1.5 ±0.8 **

68.8 % (150) 22.9 % (50) 8.3 % (18) 2.2±0.4 **

Lachman test MIS[1-3, 7, 19] BIS[1, 11] CROSS-PIN[3, 7, 11, 15, 17-19]

SUSPENSORY[2, 17, 18]

0 1+ ≥2+

42.4 % (86) 32.5 % (66) 25.1 % (51)

81.9 % (59) 16.7 % (12) 1.4 % (1)

42.5 %(167) 41.5 % (163) 16 % (63)

63.4 % (116) 31.7 % (58) 4.9 % (9)

Pivot-shift test

MIS[1-4, 7, 9, 19]

BIS[1, 4, 9, 11, 13] CROSS-PIN[3, 7, 11, 13, 15, 17, 19]

SUSPENSORY[2, 17]

0 1+ ≥2+

76.9% (210) 22% (60) 1.1% (3)

84.1% (164) 13.3% (26) 2.6% (5)

77% (321) 20.1% (84) 2.9% (12)

68.6% (118) 26.7% (46) 4.7 % (8)

APTT, anterior-posterior tibial translation ; () number of the patients included; ** mean value and standard deviation.

Table 3

.

Table 4. Subjective functional evaluation

MIS [1-6] BIS [3, 4, 6-9] CROSS-PIN[2, 5, 7, 9-12]

SUSPENSORY[1, 8, 10-12]

IKDC A B C D

15% 54.3% 20.7% 10%

45.2% 43.6% 10.2% 0.1%

41.6 % 45.6 % 11.5 % 1.3 %

31.8% 46.5% 15.1% 6.5%

Lysholm

MIS[1-6, 13-16] BIS[3, 4, 6, 7, 9, 13, 15, 16]

CROSS-PIN[2, 5, 7, 9, 14]

SUSPENSORY[1]

91.5 ± 3.7** 92.4 ± 2.0** 93.0 ± 3.0** 86**

Tegner

MIS BIS CROSS-PIN SUSPENSORY

6.3 ±0.5 ** 0-3: 22.5% ; 3-9: 77.5%

6.8±0.5 ** -

6.5 ± 0.5 ** 5-9: 100%

- 0-3: 10.5% ; 4-10: 89.5%

MIS , metal interference screw; BIS, bioabsorbable interference screw ; ** mean value and standard deviation.

Table 4

Table 5.Post-operative complications

MIS , metal interference screw; BIS, bioabsorbable interference screw.

MIS BIS CROSS-PIN SUSPENSORY

Failure 3.3 % 6. 1% 1.7 % 1.2 %

Meniscal tears 4.0 % 1.0 % 3.9 % 2.0 %

Breakage 0.4 % 0.5 % 0.9 % 1.5 %

Infection 0.7 % 1.9 % 0 % 1.6 %

Table 5