Single- and Double-Bundle Anterior Cruciate LigamentReconstruction in Patients Aged Over 50 Years

Alberto Ventura, M.D., Claudio Legnani, M.D., Clara Terzaghi, M.D., and Enrico Borgo, M.D.

Purpose: The purpose of our study was to retrospectively evaluate the outcomes after anteriorcruciate ligament (ACL) reconstruction with hamstring in patients aged 50 years or older. In addition,we present, for the first time, the outcomes of a subgroup of middle-aged patients treated withdouble-bundle (DB) reconstruction. Methods: Fifty patients aged 50 years or older underwentprimary ACL reconstruction with hamstring. Inclusion criteria were primary ACL reconstruction inactive patients. Exclusion criteria were multiligamentous injuries and a contralateral ACL-deficientknee. The mean age at surgery was 54.4 years (range, 50 to 65 years). The mean period from theinitial injury to surgery was 32.6 months (range, 3 to 125 months). Of the patients, 36 underwentsingle-bundle (SB) ACL reconstruction and 14 underwent DB reconstruction. Patients were assessedpreoperatively with physical examination (including range of motion, pivot-shift test, and instru-mented knee laxity measurement), the Lysholm score, the International Knee DocumentationCommittee scoring system, and the Tegner activity scale. Standard radiographs were taken, anddegenerative changes were graded according to the Ahlbäck radiologic classification of arthritis.Results: Patients were evaluated at a mean of 4.4 years (range, 2 to 7 years) after surgery. Asignificant improvement in knee function and symptoms was reported in most patients, withincreased Lysholm, International Knee Documentation Committee, and Tegner scores (P � .001).The outcomes of clinical assessment and instrumented laxity testing were clearly improved whencompared with preoperative status (P � .001). The level of osteoarthritis did not statistically increaseat follow-up. No statistically significant difference could be observed between the SB and DB groups(P � not significant). Conclusions: Operative treatment showed favorable outcomes in most of theACL-reconstructed patients with regard to knee stability, osteoarthritis progression, and patientsatisfaction in a cohort of subjects aged 50 years or older. Our subgroup of patients undergoing DBACL reconstruction reported average satisfactory outcomes, which did not significantly differ fromthe SB group. Level of Evidence: Level IV, therapeutic case series.

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From the Minimally Invasive Articular Surgery Unit, IstitutoOrtopedico G. Pini (A.V., C.T., E.B.), and Scuola di Specializza-zione in Ortopedia e Traumatologia, Università degli Studi diMilano (C.L.), Milan, Italy.

The authors report that they have no conflicts of interest in theauthorship and publication of this article.

Received June 23, 2011; accepted April 16, 2012.Address correspondence to Alberto Ventura, M.D., UOSD

Chirurgia Articolare Mininvasiva, Istituto Ortopedico G. Pini,Piazza Cardinal Ferrari 1, 20122 Milan, Italy. E-mail: alberto.ventura@doctoral.it

© 2012 by the Arthroscopy Association of North America

a0749-8063/11405/$36.00http://dx.doi.org/10.1016/j.arthro.2012.04.146

1702 Arthroscopy: The Journal of Arthroscopic and Related Surg

Anterior cruciate ligament (ACL) rupture is one ofthe most common knee injuries in sports. In the

oung athletic patient, the surgical treatment of anCL tear is commonly performed to restore kneeinematics, reducing the risks of subsequent injurynd the progression of degenerative changes. Becauseverage age and life expectancy are rising, physi-al activity level in the elderly population is increas-ng, and ACL injuries are becoming more frequent inhe population aged over 40 years.

Conservative treatment was frequently advocated in theast for middle-aged persons with ACL tears. In fact, somerthopaedic surgeons worried that ACL reconstruction inlder patients could lead to complications such as stiffness,

rthrofibrosis, infections, wound healing problems, or

ery, Vol 28, No 11 (November), 2012: pp 1702-1709

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1703ACL RECONSTRUCTION IN MIDDLE-AGED PATIENTS

thromboembolic disease, as well as concerns that underly-ing degenerative knee osteoarthritis could prevent a satis-factory outcome. Management usually consisted of physio-therapy, bracing, and modification of lifestyle, and authorsreported acceptable results.1-3 Ciccotti et al.1 observed aatisfactory outcome in 83% of conservatively treatedCL-deficient knees in a group ranging in age from 40 to0 years, despite a 37% reinjury rate and a remarkableodification in activity level and lifestyle.Several studies have shown that in a middle-aged

opulation with ACL tears, selected and motivatedatients may have considerable recovery in functionnd stability after surgical reconstruction, with a moreredictable return to cutting and pivoting sports.4 Op-

erative treatment showed favorable outcomes in thispatient population with regard to knee stability andpatient satisfaction, with results similar to those ob-served in a younger patient population.5-8 No in-reased risk of complications (stiffness, arthrofibrosis,nfections) was noted in middle-aged patients com-ared with younger patients.5-8

This growing body of evidence has broadly changedthe approach of the surgeons toward the management ofthe ACL-deficient knee in the elderly patients, and re-cently, several reports have focused on ACL reconstruc-tion in patients aged 50 years or older9-13 (Table 1).

On the basis of biomechanical studies and clinicaltrials, recently, a double-bundle (DB) reconstructive

TABLE 1. Summary of Studies Included in Our PaperYear

Author YearNo. of

ProceduresMean Age

(yr)Follow-up

(mo) Graft type

Blythet al.9

2003 31 54.5 (50-66) 46 (24-95) 10 BPTB21 hamstring

Steinet al.10

2006 19 54 (49-64) 24 (9-48) Allograft

Dahmet al.11

2008 35 57 (50-66) 72 (25-173) 23 allograft12 BPTB

Trojaniet al.12

2009 18 57 (51-66) 31 (12-59) Hamstring

stiet al.13

2011 20 56 (50-62) 32 (24-49) NA

Abbreviations: BPTB, bone–patellar tendon–bone; IKDC, International Knee D

technique has been proposed to better restore anatomyand biomechanics of the native ligament.14 Potentialdvantages are represented by improved rotational sta-ility and reduced risks of further knee damage andsteoarthritis onset.15,16 Because average age and life

expectancy are rising, physical activity levels in theelderly population are increasing, and the number ofmiddle-aged subjects who are more likely to practicingcutting and pivoting sports is growing.

To our knowledge, no studies exist in the litera-ture analyzing the outcomes of ACL DB reconstruc-tion in patients aged 50 years or older. The purposeof our study was to retrospectively evaluate theoutcomes after ACL reconstruction with hamstringautograft in patients aged 50 years or older withregard to clinical and radiographic findings. In ad-dition, we present the outcomes of a subgroup ofpatients treated with DB reconstruction. Our hy-pothesis was that a closer restoration of knee kine-matics through ACL DB reconstruction could leadto improved clinical outcomes.

METHODS

Study Design

We considered 50 patients aged 50 years or olderwho underwent ACL reconstruction between 2004

ing Results of ACL Reconstruction in Patients Aged 50lder

LysholmScore

Tegner Scoreat Follow-up

Arthrometer(Laxity �3 mm v

Normal Knee) Notes

93 5.2 (�1.5 changefrompreoperatively)

11 (41%) No patients reportedsymptoms ofinstability

92 NA 18 (95%) 16 of 19 returned toacceptablerecreational activitylevel

92 4.3 (�0.1 changefrompreinjury)

NA 30 (86%) returned topreinjury level ofactivity

NA NA NA Mean residualdifferential laxity3.1 mm atradiographic Telos(Telos GmbH,Marburg, Germany)stress test

89 NA 15 (75%) 85% of patientsachieved excellentor goodpostoperativeresults

Reports or O

IKDCScore

A: 5B: 20C: 6D: 0NA

90

A: 7B: 7C: 3D: 1

91

ocumentation Committee; NA, not applicable.

NG

MMMM

1704 A. VENTURA ET AL.

and 2009 for this study. Inclusion criteria were pri-mary ACL reconstruction in active patients. Exclusioncriteria were multiligamentous injuries and a con-tralateral ACL-deficient knee. The mean age at sur-gery was 54.4 years (range, 50 to 65 years; median, 54years). The mean period from the initial injury tosurgery was 32.6 months (range, 3 to 125 months).Table 2 shows complete patient demographics andanthropometric data. In 14 cases subacute reconstruc-tions occurred (�6 months after injury), whereas 34patients underwent chronic ACL reconstruction (�6months after injury). Of the patients, 36 underwentsingle-bundle (SB) ACL reconstruction and 14 under-went DB reconstruction. Selection criteria for thetype of reconstruction performed were determinedaccording to the functional request of the subjects.Patients requiring a return to cutting or pivotingsports were treated with DB reconstruction. In ad-dition, ACL DB reconstruction was reserved forpatients presenting with an ACL insertion site mea-suring at least 14 mm.17

Surgical Technique

ACL reconstruction was performed with the patientunder regional anesthesia (bi-block) and with the useof a tourniquet. Preliminary arthroscopic inspectionwas performed to confirm the diagnosis and to detectany eventual meniscus, cartilage, or ligament injury.Hamstring tendon autografts were harvested with atendon stripper through an incision over the pes anse-rinus on the anteromedial (AM) aspect of the tibia.

SB reconstruction was performed as follows. Thetibial and femoral tunnels were drilled with an ar-throscopically assisted transtibial technique. After re-moval of the remnants of the torn ACL, the tibialtunnel was drilled with the aid of a guide (Acufex;Smith & Nephew, Andover, MA) at a 55° angle in thehorizontal plane on the tibial plateau. The femoral

TABLE 2. Patient Demogr

Overall

o. of patients 50enderMale 39Female 11ean time from injury (mo) 32.6 (range, 3-125)ean weight (kg) 73.7 (SD, 6.1)ean height (cm) 171.9 (SD, 6.2)ean age at surgery (yr) 54.4 (range, 50-65)

tunnel was then drilled with the knee flexed at 90° in

the intercondylar notch posterior and lateral on themedial aspect of the lateral femoral condyle to a depthof 30 mm and a diameter matched to the width of theprepared graft, at the 10:30 clock position in the rightknee and at the 1:30 clock position in the left knee.Then, the graft was fixed proximally using a Retro-button device (Arthrex, Naples, FL). Distal lockingwas achieved through a BioRCI screw (bioabsorbablerounded cannulated interference screw; Smith &Nephew), having a diameter of 1 or 2 mm larger thanthe graft and a length of 30 or 35 mm depending onthe tunnel extent, while the knee was kept at 20° offlexion under maximal manual tension.

DB reconstruction was performed using doubledsemitendinosus tendon for the AM bundle and dou-bled gracilis tendon for the posterolateral (PL) bundle.The harvesting of the hamstring tendon graft wasperformed in the same manner as in the SB procedure.The tibial tunnel for the PL bundle was located firstusing the tip of a 55° guide (Acufex) placed in thenative PL bundle footprint on the tibial surface. Then,the guidewire for the AM tunnel was drilled with atranstibial approach by putting the tip of the drill guidein a more AM position in correspondence with theAM tibial footprint, this time using a 50° angle. Abone bridge of at least 5 mm was left between theguidewires. We first drilled the PL bundle tibial tunnelwith a diameter equal to the graft. The correspondingfemoral half-tunnel for the PL bundle was drilled asfollows: the tip of the guidewire was positioned pos-teriorly on the medial aspect of the lateral femoralcondyle. The femoral half-tunnel was then drilled witha diameter identical to that of the graft, at the 9:30clock position of the intercondylar space in the rightknee and at the 2:30 clock position in the left knee.Similarly, the AM bundle bone tunnels were preparedthrough a transtibial approach, at the 11:30 clockposition in the right knee and at the 12:30 clock

and Anthropometric Data

SB Group DB Group

36 14

29 107 4

32.2 (range, 3-125) 33.0 (range, 5-115)74.9 (SD, 5.4) 72.6 (SD, 7.1)

171.7 (SD, 6.0) 172.2 (SD, 6.3)54.7 (range, 50-65) 54.1 (range, 50-63)

aphics

position in the left knee. Then, after passing through the

Dkt

1705ACL RECONSTRUCTION IN MIDDLE-AGED PATIENTS

tibial tunnels first the graft for the PL bundle and then thegraft for the AM bundle, the cortical fixation wasachieved through the use of Retrobutton devices. Thedistal fixation was achieved with 2 Bio-Interferencescrews (Arthrex) with the knee fully extended for the PLbundle and with the knee flexed at 20° for the AMbundle under maximal manual tension. The diameter ofthe screws was 1 mm larger than that of the graft; thelength was 23 mm.

Rehabilitation Protocol

A brace-free postoperative rehabilitation protocolwas applied to all patients. Active and passive rangeof motion of the knee and isometric muscle exerciseswere started the day after the operation. For the first 4weeks, walking with partial weight bearing was al-lowed with the use of 2 crutches. Patients were en-couraged to regain proprioception and complete kneeflexion and extension. Closed kinetic chain exerciseswere performed for the first 3 months, and afterward,open kinetic chain exercises were started. Swimmingand indoor cycling were permitted after 12 weeks,jogging and noncontact sports were permitted after 5months, and return to contact sports was allowed after9 months.

Clinical Assessment

Assessment was made by the Lysholm score forpatient subjective statement,18 the International Knee

ocumentation Committee scoring system for clinicalnee stability,19 and the Tegner activity scale for pa-ient activity level.20 Objective evaluation was carried

out with a standard manual knee examination, includ-ing range of motion, Lachman test in 20° of flexion,and pivot-shift sign. In this study Lachman test andpivot-shift sign were considered either negative orpositive. An instrumented laxity tester (KT-1000 ar-thrometer; MEDmetric, San Diego, CA) was used todocument anteroposterior displacement of the tibia at134-N load at 20° of flexion. Standard anteroposteriorand lateral radiographs were taken, and degenerativechanges were graded according to the Ahlbäck radio-

TABLE 3. Concomitant Additional Surgery

Overall SB Group DB Group

Meniscectomy 28 22 6Cartilage debridement 12 9 3

logic classification of arthritis.21

Statistical Analysis

Data were analyzed with the SPSS software package,version 17.0 (SPSS, Chicago, IL). Preoperative and post-operative results were compared by use of the pairedMann-Whitney U test. Significance was set at .05.

RESULTS

Fifty patients were contacted at a mean of 4.4 years(range, 2 to 7 years) after surgery. Eighteen patientsunderwent previous meniscal surgery. Seven medialand 4 lateral meniscectomies were performed in 10patients along with ACL reconstruction. This raisedthe number of patients who had a meniscectomy to 28(Table 3). No cases of infection, deep thrombosis,neurovascular injury, or any other complication werenoted.

A detailed overview of the results of clinical assess-ment is shown in Table 4. The mean overall Lysholmscore increased (P � .001) from a preoperative meanof 62 (SD, 10.8) to 90 (SD, 6.4), showing a statisti-cally significant difference (P � .001) (Fig 1). Ac-cording to International Knee Documentation Com-mittee grading, score A was found in 15 patients(30%), score B in 32 (64%), score C in 3 (6%), andscore D in none. Outcomes of the SB and DB groupsare reported in Table 5. Clinical assessment docu-mented no statistically significant differences betweenthe SB and DB groups (P � not significant).

Twenty-two patients practiced cutting/pivotingsports at an amateur level at the time of surgery(skiing, basketball). Fourteen of them underwent DBreconstruction. Twenty-eight patients practiced non-contact sports (running, swimming). The medianTegner activity rating significantly improved (P �.001) from a preoperative mean of 4 (range, 1 to 8) to5 (range, 2 to 8) (Fig 2). The outcomes of clinicalassessment regarding Lachman test and pivot-shift

TABLE 4. Clinical Assessment Preoperativelyand Postoperatively

Preoperative Postoperative P Value

Mean Lysholm score (SD) 62 (10.4) 90 (6.4) �.001Median Tegner activity

level (range) 4 (1-8) 5 (2-8) �.001IKDC score (%) �.001

A 0 (0) 15 (30)B 4 (8) 32 (64)C 39 (78) 3 (6)

D 7 (14) 0 (0)

MI

1706 A. VENTURA ET AL.

sign were clearly improved when compared with pre-operative status (Table 6). The mean side-to-side KT-1000 value was 2.7 mm. Of the patients, 48 (96%)reported a value equal to or less than 3 mm comparedwith the contralateral knee. However, concerning kneelaxity measurements, no statistically significant differ-ence could be observed between the SB and DBgroups (Table 7). Three patients reported an extensiondeficit of 5° postoperatively.

Preoperative standard radiographs were taken (Fig3). According to the Ahlbäck radiologic classificationof arthritis, 38 patients were grade I and 12 wereconsidered grade II.

FIGURE 1. Preoperative and postoperative Lysholm score aftera mean of 4.4 years. Lysholm scores are shown as box plotsbased on the median, quartiles, and extreme values. The boxrepresents the interquartile range, which contains 50% of val-ues. The median is reported as a line across the box. Whiskersfrom minimum to maximum represent the highest and lowestvalues. A statistically significant difference (P � .05) wasobserved.

TABLE 5. Clinical Assessme

Preope

SB Group DB

Mean Lysholm score (SD) 61 (10.9) 63edian Tegner activity level (range) 4 (1-8) 4

KDC score (%)A 0 (0) 0B 2 (6) 2C 31 (86) 8D 3 (8) 4

Abbreviation: NS, not significant.

More advanced signs of arthritis were observed inthe medial compartment compared with the lateralcompartment.

Standard radiographs were obtained in 44 patientsat a mean of 4.9 years (range, 3 to 7 years) aftersurgery. At follow-up, osteoarthritis grade I accordingto the Ahlbäck classification was detected in 33 pa-tients, whereas 11 were considered grade II (P � .6)(Fig 4).

DISCUSSION

The most important findings of this study are thatoperative treatment showed favorable outcomes in

ween 2 Surgical Techniques

Postoperative

P Value SB Group DB Group P Value

NS 90 (6.9) 92 (5) NSNS 5 (2-8) 5 (2-8) NSNS NS

10 (28) 5 (36)24 (67) 8 (57)2 (6) 1 (7)0 (0) 0 (0)

FIGURE 2. Preoperative and postoperative Tegner score after amean of 4.4 years. Tegner scores are shown as box plots based onthe median, quartiles, and extreme values. The box represents theinterquartile range, which contains 50% of values. The median isreported as a line across the box. Whiskers from minimum tomaximum represent the highest and lowest values. A statisticallysignificant difference (P � .05) was observed.

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Group

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1707ACL RECONSTRUCTION IN MIDDLE-AGED PATIENTS

most of the ACL-reconstructed patients with regard toknee stability and patient satisfaction and that nostatistically significant differences were found in theoutcomes between SB and DB reconstruction in pa-tients aged 50 years or older. In addition, the level ofosteoarthritis did not statistically increase at follow-upcompared with preoperative status.

ACL reconstruction in the population aged 50 yearsor older is still an issue of debate because no consen-sus exists among surgeons on whether to treat middle-aged patients with an ACL lesion conservatively orsurgically. Conservative treatment has been tradition-ally reserved for low-demand patients and consists ofmodification of activities, quadriceps muscle strength-ening, proprioception exercises, and bracing. In thestudy by Ciccotti et al.1 nonoperative treatmentielded satisfactory outcomes in 83% of patients aged0 to 60 years with an ACL tear. However, patientsad to renounce their return to competitive pivotingports and had to cope with knee instability.

It has been reported that selected and motivatediddle-aged patients with an ACL tear may have

onsiderable recovery in function and stability afterurgical reconstruction, with a more predictable returno cutting and pivoting sports and without increasedisk of complications, such as stiffness, arthrofibrosis,nd infections, compared with younger patients.5-8

With increased activity-related injury and to complywith patients’ requests to return to preinjury levels,nowadays, the cutoff age between surgical and non-surgical treatment is higher.

In our case series no major complications were

TABLE 6. Comparison of Stability Preoperativelyand Postoperatively

Preoperative Postoperative P Value

Mean side-to-side anteriorlaxity �.001

�1 mm 0 (0%) 9 (18%)1-3 mm 0 (0%) 39 (78%)3-5 mm 6 (12%) 2 (4%)�5 mm 44 (88%) 0 (0%)ean side-to-side anterior

laxity (SD) 5.5 (1.3) 2.7 (0.8) �.001ositive Lachman test �.001Positive 50 (100%) 1 (2%)Negative 0 (0%) 49 (98%)

ositive pivot-shift test �.001Positive 45 (90%) 1 (2%)Negative 5 (10%) 49 (98%)

observed. The mean subjective results were satisfac-

tory, and most patients (92%) stated that they wouldhave undergone surgery again.

The clinical and functional results of our study aresimilar to those previously reported in the same agegroup. Blyth et al.9 reported a mean Lysholm score of 93,and Stein et al.10 and Dahm et al.11 reported a value of2; these results are comparable to the mean Lysholmcore of 90 in our series.

Our scoring systems also show that our data areomparable to those observed in younger patients aseported in other studies.

On the basis of biomechanical studies and clinicalrials, recently, a DB reconstructive technique haseen proposed to better restore the anatomy and bio-echanics of the native ligament.14 Reports have

shown that the reconstruction of both bundles of theACL leads to improved knee stability, especially withregard to rotatory loads.22,23 However, clinical out-comes between the 2 procedures are still controver-sial, and objective data documenting a difference be-tween the 2 reconstructive methods are still lackingbecause studies have shown statistically significantdifferences only with respect to the pivot-shift test.24

The choice for ACL DB reconstruction should bebased on ACL insertion site and femoral intercondylarnotch dimensions because it requires adequate foot-print size to place 2 femoral tunnels.17 In fact, in theresence of a narrow notch or when a patient has annsertion site less than 14 mm in diameter, DB recon-truction is not indicated.25

To our knowledge, no studies exist in the literatureanalyzing the outcomes of ACL DB reconstruction inpatients aged 50 years or older. Our subgroup of

TABLE 7. Stability Outcomes Between 2Surgical Techniques

SB Group DB Group P Value

ean side-to-side anteriorlaxity NS

�1 mm 6 (17%) 3 (21%)1-3 mm 29 (80%) 10 (71%)3-5 mm 1 (3%) 1 (7%)�5 mm 0 (0%) 0 (0%)ean side-to-side anterior

laxity (SD) 2.8 (0.9) 2.6 (0.6) NSositive Lachman test NSPositive 1 (3%) 0 (0%)Negative 35 (97%) 14 (100%)

Positive pivot-shift test NSPositive 1 (3%) 0 (0%)Negative 35 (97%) 14 (100%)

Abbreviation: NS, not significant.

1708 A. VENTURA ET AL.

patients undergoing DB ACL reconstruction reportedaverage satisfactory outcomes with regard to subjec-tive and objective outcomes. Although our cohort ofpatients is relatively small, our data do not show a

statistically significant difference between the 2 sur-gical techniques; thus the potential advantages of im-proved rotational stability do not considerably influ-ence the outcomes. In addition, although restoring

FIGURE 3. Preoperative radio-graphs of a DB ACL-reconstructed patient.

FIGURE 4. Postoperative ra-diographs of a DB ACL-reconstructed patient.

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1

1

1

1

1

1

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2

2

1709ACL RECONSTRUCTION IN MIDDLE-AGED PATIENTS

ACL anatomy and biomechanics more closely couldtheoretically reduce the risks of further knee damageand osteoarthritis onset, we could not find any differ-ences between the 2 subgroups of patients consideredin terms of osteoarthritis progression.

The limitation of this study is the relatively smallsample size and the lack of a control group of nonop-eratively managed patients. However, we commonlypropose nonoperative treatment to low-demand pa-tients who can cope with instability problems and inwhom quality of life is not affected by knee problems.Thus a comparison between surgically and conserva-tively treated patients would not have been meaning-ful because of patient selection bias.

Despite these weaknesses, our data suggest thatACL reconstruction can be successful in appropriatelyselect, motivated older patients. To maximize the out-come, selection criteria must be strict, and the injuredknee must not have more than minimal arthriticchanges. However, further randomized trials and com-parative studies are required to drive the surgeons todetermine the correct therapeutic approach for theACL-deficient knee in the elderly population.

CONCLUSIONS

Operative treatment showed favorable outcomes inost of the ACL-reconstructed patients with regard to

nee stability, osteoarthritis progression, and patientatisfaction in a cohort of subjects aged 50 years orlder. Our subgroup of patients undergoing DB ACLeconstruction reported average satisfactory out-omes, which did not significantly differ from the SBroup.

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