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Medium-Term (5-Year) Comparison of the FunctionalOutcomes of Combined Anterior Cruciate Ligament and

Posterolateral Corner Reconstruction Compared With IsolatedAnterior Cruciate Ligament Reconstruction

Matthew Cartwright-Terry, F.R.C.S.(Tr&Orth), Jonny Yates, M.R.C.S.,Chin K. Tan, F.R.C.S.(Tr&Orth), Ioannis P. Pengas, F.R.C.S.(Tr&Orth),Joanne V. Banks, F.R.C.S.(Tr&Orth), and Michael J. McNicholas, M.D.

Purpose: To present a 5-year comparison of the functional outcomes of combined anterior cruciate ligament (ACL) andposterolateral corner (PLC) reconstruction with those of isolated ACL reconstruction. Methods: All patients werereviewed clinically and completed knee function questionnaires prospectively, by use of the International Knee Docu-mentation Committee (IKDC) 2000, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Lysholm scoring sys-tems, preoperatively and at 1, 2, and 5 years postoperatively. Patients who underwent combined ACL-PLC reconstructionwere identified and reviewed. These patients had intact lateral collateral ligaments. A comparison group was created froma group of patients who underwent isolated ACL reconstruction. The ACL group was selected to have the same profilewith regard to age, sex, and meniscal procedure. Results: There were 25 patients in the ACL-PLC group and 100 in theACL group. All patients underwent restoration of their PLC function as shown on dial testing. The preoperative values forall KOOS measures and the Lysholm score were significantly lower in the ACL-PLC group than in the ACL group(P < .001). The IKDC score was not significantly different. All knee scores showed a significant improvement in bothgroups postoperatively at 1, 2, and 5 years (P < .001). At 5 years, the KOOS symptoms subscore (P < .001), KOOS painsubscore (P < .001), KOOS sports subscore (P < .001), KOOS quality-of-life subscore (P < .05), KOOS activitieseofedailyliving subscore (P < .001), aggregate score for all KOOS parameters (P < .001), and Lysholm score (P < .001) weresignificantly lower in the ACL-PLC group than in the ACL group. At 5 years, the IKDC scores were not significantlydifferent. All patients in the ACL-PLC group resumed preinjury employment, and 23 of 25 had resumed sports.Conclusions: Combined ACL-PLC injuries have greater morbidity than isolated ACL injuries. However, return to workand sporting activity is possible in most cases after combined ACL-PLC reconstruction. The KOOS for sport outcomessuggests that sports were resumed at lower functional levels. Level of Evidence: Level III, case-control study.

From the Department of Trauma and Orthopaedic Surgery, Aintree Uni-rsity Hospital NHS Foundation Trust (M.C-T., M.J.M.), and Department ofrauma and Orthopaedic Surgery, Royal Liverpool and Broadgreen Uni-rsity Teaching Hospitals (J.Y., J.V.B.), Liverpool; Department of Traumand Orthopaedic Surgery, Royal National Orthopaedic Hospital NHS Trust.P.P.), Brockley Hill; School of Health Care Professions, University of Salford.J.M.), Salford, England. And Lam Wah Ee Hospital (C.K.T.), Penang,

ingapore.The authors report that they have no conflicts of interest in the authorship

nd publication of this article.Received July 3, 2013; accepted February 27, 2014.Address correspondence to Matthew Cartwright-Terry, F.R.C.S.(Tr&Orth),epartment of Trauma and Orthopaedic Surgery, Aintree University HospitalHS Foundation Trust, Aintree University Hospital, 14 South Mossley Hilload, Liverpool, L19 3PZ, England. E-mail: mctdoc@hotmail.com� 2014 by the Arthroscopy Association of North America0749-8063/13456/$36.00http://dx.doi.org/10.1016/j.arthro.2014.02.039

Arthroscopy: The Journal of Arthroscopic and Related

igamentous injuries to the knee are common, ac-1,2

Lcounting for 34% to 48% of all knee injuries.

Sports-related injuries to the knee and knee ligamentsare increasing in incidence, as more persons areparticipating in sports.3 Posterolateral rotatory insta-bility (PLRI) was first described in 1976,4 but theposterolateral corner (PLC) of the knee has becomeappreciated in recent years. The incidence of PLC injuryseen on magnetic resonance imaging has been reportedto be apparent in 16% of all knee ligament injuries.5

PLC injury is usually the result of high-energytrauma, by either direct or indirect mechanisms.6

PLRI is rare in isolation but occurs most frequently inassociation with injury to the anterior cruciate ligament(ACL) and/or the posterior cruciate ligament.5 Theseinjuries result in severe functional disability, with pain,

Surgery, Vol -, No - (Month), 2014: pp 1-7 1

2 M. CARTWRIGHT-TERRY ET AL.

instability, and deterioration of the articular cartilage ifleft untreated,7 which has also been replicated in ananimal model.8,9 Unrecognized PLC injury can affectthe integrity and results of cruciate ligament re-constructions.10-13 Therefore it is recommended thatthe PLC be repaired or reconstructed at the time ofcruciate ligament reconstruction to decrease the risk ofcruciate reconstruction failure.11-13 Similarly, PLCreconstruction alone is at great risk of attenuation andfailure if the integrity of the ACL is not restored at thesame time.14

Despite increasing awareness of ACL-PLC injuries,there is little published information on the outcome ofACL-PLC reconstruction and patients’ prognoses. Weare aware of only a single article comparing theoutcome of these patients with an isolated ACL injurygroup.15 The article had 24 months’ follow-up and wasfrom a South Korean cohort. There may be consider-able differences between these patients and our pre-dominantly white patient population.16

The purpose of this study is to present a 5-yearcomparison of the functional outcomes of combinedACL and PLC reconstruction with isolated ACL recon-struction. Our hypothesis is that patients with ACL-PLCreconstruction will have similar outcomes to patientswith isolated ACL reconstruction up to 5 yearspostoperatively.

MethodsAll patients undergoing soft-tissue knee surgery in

our unit were assessed clinically preoperatively and at 3and 6 months and 1, 2, and 5 years postoperatively. Allpatients also completed questionnaires prospectively atthese times using the Lysholm Knee Scoring Scale, In-ternational Knee Documentation Committee (IKDC)2000 Ligament Subjective Knee Evaluation Form, andKnee Injury and Osteoarthritis Outcome Score (KOOS).All data were prospectively recorded in our secure kneeinjury database. We complied with the hospital trust’srequirements, and all patients consented to be involvedin this study. Because this was an observational studyfrom data collected as part of routine follow-up, ethicalapproval was not required.A database search identified patients who underwent

ACL-PLC reconstruction between October 2001 andDecember 2006. Excluded from the study were patientswith acute repairs (<3 weeks after injury); injuries tothe medial collateral ligament, posterior cruciate liga-ment, or posteromedial corner; isolated PLC injuries;associated fractures; concomitant high tibial osteotomywith the ligament reconstruction; abnormal contralat-eral limb examination findings (in the clinic or underanesthesia); or abnormal contralateral knee function.Data were also collected from the operative records andhospital case notes. Thirty-six patients made up thiscohort, but because there were several techniques used

in reconstruction of the PLC, we decided to includepatients who underwent only 1 technique (split bicepstenodesis) to reduce heterogeneity. The largest group ofACL-PLC reconstructions comprised patients who hadsplit biceps tenodesis. Patients were only deemedeligible for split biceps tenodesis if the lateral collateralligament (LCL) was intact and the bicipital aponeurosiswas of satisfactory quality with an intact insertion intothe fibula head.The database is a continuous series of knee ligament

reconstructions and was used to create a comparisongroup of patients who had undergone isolated ACLreconstruction. The group was matched to the ACL-PLCcohort for age, sex, and any meniscal procedures car-ried out. This group was kept as large as possible toreduce the possibility of statistical error.The correction of anteroposterior (AP) tibial trans-

lation achieved by cruciate ligament reconstruction wasmeasured intraoperatively in both groups, just beforethe first skin incision was made, as well as after woundclosure and at each follow-up appointment, with aRolimeter (Aircast, Vista, NJ). The Rolimeter is a deviceused to measure AP translation and has been shown tobe equally as effective as the KT-1000 (MEDmetric, SanDiego, CA).17 The dial test was performed with theknee at 30� and 90� of flexion, and the amount ofexternal rotation was recorded for the uninjured kneepreoperatively and for the operated knee preopera-tively, postoperatively, and at each follow-up visit. Anabnormal dial test finding (increased external rotation>10�) preoperatively was an indication of PLRI andtherefore required reconstruction of the PLC concomi-tantly with the ACL reconstruction. The results of thedial test were compared to assess the effectiveness ofthe PLC reconstruction. Varus laxity was evaluated andwas not present in any of our patients (exclusion cri-terion). It was also not present when assessed in allpatients at each postoperative follow-up visit.

Surgical Technique and Rehabilitation ProgramThe senior author (M.J.M.) carried out all surgical

procedures. Patients were assessed in the clinic by useof the dial test to determine whether PLC reconstruc-tion was required; if the LCL was intact and the bicipitalaponeurosis was of satisfactory quality with an intactinsertion into the fibula head, the patient was selectedto undergo split biceps tenodesis. This was confirmedwith the patient under anesthesia before surgery. Anymeniscal pathology that required surgical treatmentwas addressed during the same anesthesia period.Split biceps tenodesis is the preferred technique of thesenior author, and patients undergoing this techniquemake up our cohort. ACL reconstruction was per-formed arthroscopically with a 55� tibial tunnel, andthe femoral tunnel was drilled by the transtibial tech-nique. The grafts used were 18 hamstring grafts and 7

FIVE-YEAR COMPARISONS OF ACL-PLC TO ACL 3

boneepatellar tendonebone grafts in the ACL-PLCpatients and 66 hamstring grafts and 34 boneepatellartendonebone grafts in the ACL patients. During thetightening of an ACL graft, there is a significant increasein tibial external rotation in knees with a PLC injurycompared with knees in which the PLC is intact.18 It istherefore recommended that in cases of combined ACL-PLC injury, the PLC structures should be reconstructedbefore tensioning the ACL graft. These procedures werefollowed in this study. When isolated popliteofibularligament reconstruction was required and the bicipitalaponeurosis was of satisfactory quality with an intactinsertion into the fibula head (as was the case for all ofour ACL-PLC patients), then the aponeurosis was har-vested. The common peroneal nerve was first identifiedat the fibula neck and traced proximally to ensure thatit was protected throughout the procedure. All of theaponeurosis except for the anterior and posterior 2-mmedges was used, taking a graft of up to 10 cm from thefibula head. It then underwent tubularization by No. 5Ethibond (Ethicon, Somerville, NJ) whipstitch, withcare taken to “cinch” this by pulling in the line of itsintended action, that is, toward the hip. This was passeddeep to the muscle belly of the biceps femoris and theLCL and was then fixed into a 7-mm-diameter bonetunnel, which was 50 mm in length in the most ante-rior part of the popliteus fovea. The graft was pulledinto the tunnel, held under tension, and fixed with theknee in 30� of flexion with the foot held in neutralrotation, by use of a 7 � 25emm RCI screw (Smith &Nephew Endoscopy, Andover, MA). Before 2004, pa-tients underwent PLC fixation with the tibia at 30� offlexion with internal rotation. After oral communica-tion with La Prade (2004) discussing over-constraint ofthe knee, our technique changed, with fixation of thePLC in neutral rotation. None of our patients had over-constraint.All patients followed the unit’s standard rehabilitation

program under the close supervision of senior physio-therapists, which commenced with preoperative musclestrengthening. Patients who underwent isolated ACLreconstruction had physiotherapy postoperatively toensure return of full range of motion initially and thenproprioception, strength, endurance, and ultimately,sports-specific training before being allowed to returnto contact sports. Patients who underwent ACL-PLC

Table 1. Intraoperative AP Rolimeter Measurements in ACL and

Contralateral Knee Preopera

ACL (mm) 9.4 (2.6) 13.8 (ACL-PLC (mm) 9.7 (2.7) 14.0 (Mann-Whitney P value .20 .50

NOTE. Standard deviations are shown in parentheses.

reconstructions were placed into a long lever bracewith motion limited between 10� and 90� for 6 weeksand were kept noneweight bearing; from 6 to12 weeks, the motion was 0� to 120� with partialweight bearing, increasing to full weight bearing ascomfortable, and from 12 weeks, patients were weanedoff the brace. Patients were not allowed to return tosports training/conditioning (noncontact) until after6 months in the ACL group and 9 months in the ACL-PLC group and were not allowed to return to compet-itive sports until after 9 months in the ACL group and12 months in the ACL-PLC group.The preoperative and postoperative Lysholm, KOOS,

and IKDC 2000 scores were compared in the ACL-PLCand ACL groups. The scores and the Rolimeter datawere analyzed with the Mann-Whitney U test, by use ofSalstat software, version 2 (Salstat, Cardiff, Wales). Thelevel of significance was taken as P < .05.

ResultsTwenty-five patients were identified as having un-

dergone ACL-PLC reconstructions. No patients werelost to follow-up. Three patients were women. Themean age was 34.0 years (range, 23 to 50 years). Theright knee was injured in 20 patients and left knee in 5.The mean duration of follow-up was 84.5 months(range, 70 to 129 months). The mean time from injuryto surgery was 27 months (range, 1 to 121 months).Reasons for delay in surgery included patients who didnot present for many months and patients who pre-sented as tertiary referrals and had already beenassessed and treated at other hospitals. The mechanismsof injury were as follows: sports in 22 patients, roadtraffic incidents in 2, and a fall in 1.The ACL group consisted of 100 patients, 92 men and

8 women. The mean age was 36.0 years (range, 20 to52 years). Sixty-three patients had right knee injuries,and 37 patients had left knee injuries.A number of patients in both groups had meniscal

injuries that required surgical treatment. In the ACL-PLC group these included 7 medial meniscus pro-cedures (5 underwent debridement and 2 wererepaired) and 13 lateral meniscus procedures (10 un-derwent debridement and 3 were repaired). The ACLgroup included 49 medial meniscus procedures (3 wererepaired) and 31 lateral meniscus procedures (2 were

ACL-PLC Groups at 30�

Injured Side

tively

Follow-Up

1 yr 2 yr 5 yr

3.7) 11.9 (2.1) 11.8 (2.1) 10.1 (1.8)4.4) 13.2 (3.0) 12.2 (2.2) 11.3 (2.0)

.14 .44 .50

Table 2. Intraoperative AP Rolimeter Measurements in ACL and ACL-PLC Groups at 90�

Contralateral Knee

Injured Side

Preoperatively

Follow-Up

1 yr 2 yr 5 yr

ACL (mm) 7.2 (1.9) 7.2 (2.9) 8.4 (1.8) 8.0 (2.1) 7.0 (1.2)ACL-PLC (mm) 7.4 (2.0) 7.6 (2.7) 7.9 (1.5) 8.2 (1.2) 6.3 (1.1)Mann-Whitney P value .18 .49 .35 .26 .16

NOTE. Standard deviations are shown in parentheses.

4 M. CARTWRIGHT-TERRY ET AL.

repaired). (The groups had the same proportion of pa-tients with meniscal injuries; however, 4 patients in theACL-PLC group and 17 patients in the ACL group hadboth medial and lateral meniscal injuries.) There wasno statistical difference between the groups.Rolimeter measurements were recorded in 23 pa-

tients in the ACL-PLC group and 77 in the ACL group,as shown in Tables 1 and 2. Ligamentous re-constructions in both groups had similar outcomes at alltime points. The difference in tibial external rotationbetween the 2 knees as measured by the dial test isshown in Figs 1 and 2. There was a clear improvementin rotational testing at 30� and 90� after PLC recon-struction and, therefore, correction of PLRI. Measure-ments of the rotation of the knees were assessed at alltime points, and only 1 patient had a positive dial testfinding at further follow-up, at 5 years, which occurredas a result of a contact injury while playing football. Nopatients in the ACL-PLC group showed evidence ofvarus laxity.The results and analyses of the functional outcome

scores for both groups are shown in Table 3 and in Figs3 to 5. Patients in the ACL-PLC group had statisticallyworse scores than those in the ACL group for the KOOSsymptoms subscore, KOOS activitieseofedaily livingsubscore, KOOS sports subscore, and aggregate score

Fig 1. Preoperative dial test findings in patients undergoingcombined ACL-PLC reconstruction at 30� and 90�. The IKDCexamination form classifies these values as follows: 5� or less,normal; 6� to 10�, nearly normal; 11� to 19�, abnormal; and20� or greater, severely abnormal.

for all KOOS parameters at all time points and in theKOOS sports subscore and KOOS quality-of-life sub-score at most time points. The Lysholm scores wereworse for the ACL-PLC group at all points, but theIKDC scores only showed a difference at the 2-yearreview.

ComplicationsOne patient in the ACL-PLC group, early in the series,

had prominence of the screw and washer/soft-tissuewasher at the femoral tunnel used for PLC recon-struction, which were removed after 12 months. Thesenior author’s method of fixation was changed to anRCI screw. None of these patients (23 patients) haverequired removal. One patient (already mentioned)had a reinjury to the PLC after 5 years and awaitsrevision reconstruction. Other complications included 2superficial infections: 1 in the ACL anterior wound,treated with oral antibiotics, and 1 stitch abscess at thesite of inside-out medial meniscal repair, requiringsurgical debridement. The senior author’s method ofmeniscal repair has changed to an all-inside techniqueusing Fast-Fix (Smith & Nephew Endoscopy). One

Fig 2. Dial test findings at 1 year postoperatively in patientsundergoing combined ACL-PLC reconstruction at 30� and90�. The measurement taken is the increased external rota-tion seen in the injured limb compared with the uninjuredlimb. The IKDC examination form classifies these values asfollows: 5� or less, normal; 6� to 10�, nearly normal; 11� to19�, abnormal; and 20� or greater, severely abnormal. There isa clear improvement in the test results. The 2-year and 5-yearresults are the same other than in 1 patient who showedincreased external rotation at 5-year follow-up.

Table 3. IKDC 2000, KOOS, and Lysholm Scores in ACL and ACL-PLC Groups Preoperatively and at 1, 2, and 5 Years’ Follow-Up and P Values

Preoperatively

Follow-Up

1 yr 2 yr 5 yr

ACL ACL-PLC P Value ACL ACL-PLC P Value ACL ACL-PLC P Value ACL ACL-PLC P Value

IKDC score 50 53 .44 82 83 .095 87 80 < .05* 86 90 < .001*KOOS

Symptoms 53 44 <.001* 86 74 <.001* 89 79 <.001* 89 78 <.001*Pain 63 48 <.001* 90 79 <.001* 90 91 .35 89 78 <.001*ADL 55 38 <.001* 91 67 <.001* 92 67 <.001* 91 90 <.05*Sports 48 25 <.001* 86 70 <.001* 90 72 <.001* 83 87 <.001*QOL 52 44 <.001* 81 84 .22 86 72 <.001* 83 75 <.05*

Aggregate score for allKOOS parameters

54 40 <.001* 87 75 <.001* 89 76 <.001* 87 82 <.001*

Lysholm score 53 35 <.001* 89 81 <.001* 91 73 <.001* 88 77 <.001*

ADL, activities of daily living; QOL, quality of life.*Statistically significant.

FIVE-YEAR COMPARISONS OF ACL-PLC TO ACL 5

patient had failure of the meniscal repair because of anew injury during sports participation 18 months post-operatively. In theACL group therewere 3 complications:2 patients had rerupture of the ACL grafts, both of whichwere successfully revised, and1patienthadarthrofibrosis,which responded to intensive physiotherapy.At the time of latest follow-up, all patients in both the

ACL-PLC and ACL groups had resumed their preinjuryemployment. Twenty-three of the patients in the ACL-PLC group and all patients in the comparison group hadresumed sports.

DiscussionPatients in the ACL-PLC group had statistically and

clinically worse scores than those in the ACL groupfor the KOOS symptoms subscore, KOOS activitiese

Fig 3. Box-and-whisker plot for IKDC 2000 scores. The timepoints are preoperatively (preop) and at 1, 2, and 5 years’follow-up.

ofedaily living subscore, KOOS sports subscore, andaggregate score for all KOOS parameters at all timepoints and in the KOOS sports subscore and KOOSquality-of-life subscore at most time points. Clinical sig-nificance in all the KOOS values is defined as a differencegreater than 8 points.19 The Lysholm scores were worsefor the ACL-PLC group at all points, but the IKDC scoresonly showed a difference at the 2-year review. All of thelower functional scores in the ACL-PLC group werefound despite correction of PLRI as shown by results ofthe dial test. Therefore the presence of a PLC injury doescause significantly increased morbidity in patients withan ACL injury, contrary to the findings of Kim et al.20

Preoperatively, there was no difference in the groupsin AP translation at 30� or at 90� (Tables 1 and 2).Though incomplete, these follow-up proportions arecomparable with the Swedish registry experience.21

The groups had similar results throughout follow-up.Comparison of the contralateral knees in the 2 groupsshowed no difference in AP translation, suggesting thatno constitutional laxity difference between the groupsexisted. There was no difference in AP translationalinstability between the 2 groups, although Kim et al.15

found slightly less AP motion in patients who had un-dergone ACL-PLC reconstruction. Both groups had areduction in their AP motion at 30� at the 5-year point,which was unexpected. Reconstruction of the PLC hasbeen shown to restore rotatory instability,20 which wasconfirmed in our postoperative patients by restorationof normal rotation on dial testing.PLC injuries treated nonoperatively have not shown

any major difference in IKDC scores up to 2 years.22 OurIKDC scores did not show major differences either,whereas the other scoring systems did. Perhaps the IKDCscore is not sufficiently sensitive to show the difference.Several procedures have been proposed to reconstruct

the PLC, but to date, no single technique has beenuniversally accepted. However, a recent comparison of

Fig 4. Box-and-whisker plot for aggregate scores for all KOOSparameters (KOOS All). The time points are preoperatively(preop) and at 1, 2, and 5 years’ follow-up.

6 M. CARTWRIGHT-TERRY ET AL.

anatomic reconstruction of the PLC versus the modifiedbiceps rerouting technique has shown that theanatomic technique yielded slightly better outcomes.20

An increased risk of over-correction using the modi-fied biceps technique was noted (20% v 5%), but wehave not experienced this in our patients. Surgicaltreatment of PLRI must address all components of theinjury, including injuries to the cruciate ligaments,menisci, medial knee ligaments, and articular cartilage,as well as associated fractures, as indicated.23 Werecommend the use of split biceps tenodesis only whenthe LCL is intact and functioning properly.

Fig 5. Box-and-whisker plot for Lysholm scores. The timepoints are preoperatively (preop) and at 1, 2, and 5 years’follow-up.

LimitationsOur study is a retrospective study. Although there

were similar proportions of meniscal injury in bothgroups, there was a greater proportion of medialmeniscal tears in the ACL group. The medial meniscusacts as a secondary stabilizer to AP translation of thetibia relative to the femur. However, recent cadavericwork has shown no difference in AP motion in thepresence of increasing severity of meniscal tears with afunctioning ACL or ACL reconstruction until the root ofthe meniscus is transected.24 There was a modificationof the rotational position of the tibia during fixation ofthe biceps tenodesis early in our series. However, therewere no cases in which the graft was either too tight ortoo lax.

ConclusionsCombined ACL-PLC injuries have greater morbidity

than isolated ACL injuries. However, return to workand sporting activity is possible in most cases aftercombined ACL-PLC reconstruction. The KOOS for sportoutcomes suggests that sports were resumed at lowerfunctional levels.

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