a Departamento de Ortopedia, Santa Casa de São Paulo, São Paulo, SP, Brasil
b Serviço de Ortopedia e Traumatologia, Hospital Israelita Albert Einstein, Universidade Federal de São Paulo (Unifesp), São Paulo, SP,Brasil
c Instituto de Ortopedia, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo (USP), São Paulo, SP, Brasil
d Escola Paulista de Medicina, Universidade Federal de São Paulo (Unifesp), São Paulo, SP, Brasil
Introduction
Surgery to reconstruct the anterior cruciate ligament (ACL) isfrequently performed within orthopedic practice.
The ACL acts as an essential stabilizer within the biome-chanics of the knee. In addition to being considered to be theprimary stabilizer against anterior translation of the tibia, itacts as a secondary stabilizer against excessive internal rota-tion and valgus and varus stress.
Studies have also demonstrated that it diminishes the pos-sibility of joint degeneration, since it promotes protection forthe cartilage and menisci.
Tearing of this important ligament is common in high-performance sports. In making changes in direction or rapiddeceleration with the foot planted on the ground, individ-uals may promote valgus stress and stress through internal orexternal rotation, thereby injuring the ligament without directtrauma. Once the injury has become established, the patientwill present frequent episodes of instability, pain, edema anddiminished function. For this reason, the possibility of retur-ning to sports activities with the same vigor and the samemobility is low.
Choosing the best autologous graft for ACL reconstruction,in knees with insufficiency of this ligament, is a matter fordiscussion. Grafts taken from the central third of the patellarligament, as described by Campbell,4were widely used in the1980s and 1990s. At the end of the 1990s, use of the semitendi-nosus and gracilis flexor tendons was described by Macey5andthese grafts started to be used more frequently.
The ACL is composed of two bands: posterolateral, whichmainly stabilizes rotational movements; and anteromedial,which stabilizes movements of anteroposterior transla-tion. Through anatomical studies, a tendency toward ACLreconstruction using the single-band anatomical techniquehas been noted.
Today, with technological advances, arthroscopic intra-articular reconstruction makes it possible to reduce postop-erative morbidity,9but divergences between surgeons stillexist regarding the best graft to use.
Materials and methods
This was a blinded randomized controlled clinical trial.Twenty-seven patients of both sexes (25 males, 92.6%, andtwo females, 7.4%) aged 18-48 years (mean: 31.7) who pre-sented ACL injuries were prospectively evaluated. The rightside was affected in 19 (70.4%) and the left side in eight (29.6%).Twelve (44%) presented lesions of the medial meniscus andone patient had lesions of both the medial and the lateralmeniscus.
The inclusion criteria required that the patients shouldpresent a unilateral ACL tear and the absence of surgicalantecedents or previous pathological conditions in the kneeaffected.
These patients were randomly divided into two groups,through a draw that determined the type of graft (patellar orflexor) to be used in ACL reconstruction surgery.
Group A, composed of 14 patients, underwent ACL recon-struction using autologous grafts from the flexor tendons,while group B, with 13 patients, received a graft from the patel-lar tendon.
In both groups, the single-band anatomical technique wasused for arthroscopic intra-articular ACL reconstruction, andgraft fixation was ensured using an absorbable interferencescrew.
After the reconstruction, both groups were referred to thesame early rehabilitation program, which was conducted indi-vidually by trained professionals.
All the patients were evaluated at the outpatient clinicby the same researcher, one, three and six months after theoperation. The International Knee Documentation Commit-tee (IKDC) 200010and Lysholm protocols were followed.11TheIKDC is composed of 10 objective questions, subdivided intoseven on symptoms, two on sports activities and one on func-tionality before and after the injury. The modified Lysholmscale is composed of eight questions in which the options areclosed responses, such that the final result is expressed thus:from 95 to 100 points as "excellent"; from 84 to 94 as "good";from 65 to 83 as "fair"; and 64 or under as "poor".11Afterthe data-gathering, these data were subjected to descriptivestatistical analysis using percentage frequencies.
The statistical analysis was performed using the followingsoftware: SPSS®V17, Minitab®16 and Excel Office®2010. Theconfidence interval (p) of 95% was used in parametric statis-tical tests, since the data were quantitative and continuous,and the central limit theorem was used, which ensured nor-mal distribution. Thus, there was no need to test the normalityof the residuals and parametric tests were used directly, giventhat these are more powerful than nonparametric tests suchas ANOVA and equality of two proportions.
Surgical technique
The two groups differed regarding the graft to be used (Fig. 1),which was harvested from the respective donor areas usingroutine procedures. The reconstruction was done using theChambat technique and was the same for both groups.
After arthroscopy and treatment of associated lesions, thetunnels were constructed independently, from inside to out-side. By means of a lateral access, 2 cm above the lateralepicondyle, a guidewire was introduced using a tibial guideadapted for constructing a femoral tunnel, at an angle of80-90?(Figs. 2 and 3), which emerged between the joints,between the origins of the two bands (the footprints) of thelateral condyle at the anatomical location of the ACL on thefemur. Using this guidewire, progressive drilling with a bitcorresponding to the thickness of the graft was performed.
The tibial tunnel was constructed with the remains of theACL on the tibia as a reference point, or in parallel to the pos-terior margin of the anterior cornu of the lateral meniscus,
with progressive drilling. The graft was passed through fromdistally to proximally, using two Ethibond 2.0 threads. Afterthis, the graft was fixed using absorbable interference screwsin the femur and tibia, respectively13(Fig. 4).
Results
To analyze the results from the groups after the surgical treat-ment, the parameters from the IKDC index and the functionalparameters from the Lysholm scale were used in the first, thirdand sixth months after the operation.
The Lysholm functional scale presented a mean score of71.6 out of 100 in group A, in the first month, while group
presented mean of 75. At the end of the sixth month, theypresented the same mean scores of 96.6 (Fig. 5).
The evaluation using the IKDC scale showed that in the firstmonth, the knee assessments on the majority of the patientswere close to normal, both in group A (85.7%) and in groupB (76.9%). In the sixth month, 92.9% of the patients in groupA were assessed as normal and 100% in group B. However,statistically, neither the Lysholm nor the IKDC scale presentedany significant differences, with p > 0.05 (Fig. 6).
Both groups presented limitations regarding the range ofmotion in the first month after the operation. In relation toflexion, 14.3% of the patients in group A and 7.7% in groupB presented limitations. In relation to extension in the firstmonth, group A was already free from limitations, while 15.4%of the patients in group B presented limitations. After therehabilitation with physiotherapy, there were improvementsamong the patients in both groups and no joint range-of-motion deficits were seen in the sixth month. Statistically,there were no significant differences between the groups.
From the evaluation using the IKDC scale, the criteria ofgraft donor area and anterior knee pain did not present anystatistically significant differences at the end of the sixthmonth, in both groups (Figs. 7 and 8). Group B presented twocases of healing that was delayed until the third month.
In the evaluation using the Lachman test, the results ingroup B were better in the third and sixth months, with trans-lation of 1-2 mm in 100%, while in group A, 42.9% of thepatients presented translation of 3-5 mm (Table 1).
Regarding the anterior drawer test, there were statisticaldifferences in the first and third months. In the first month,57.1% of group A presented anterior translation of 0-2 mm,while 100% of group B presented this. In the third month,35.7% of group A presented anterior translation of 0-2 mm,
while there was a fall to 84.6% in group B. At the end of thesixth month, group B presented a tendency toward less ante-riorization of the tibia (Table 2).
Regarding the ligament evaluation overall (i.e. Lachman,"full stop", anterior drawer, posteriorization of the tibia,medial and lateral opening and pivot shift), groups A and Bdid not present any differences in their results, in any of theevaluations.
Discussion
ACL reconstruction has been widely discussed over recentyears. These injuries occur frequently, especially in the agegroup from 20 to 40 years. For a long time, the patellar ten-don was chosen as the main source of grafts,14but because ofthe morbidities presented, some authors have chosen to useflexor tendons. This has led to many comparative studies.
In 2001, Eriksson et al.15demonstrated that using the patel-lar tendon produced a slight advantage in relation to stability.On the other hand, in a meta-analysis in 2005, Prodromoset al.16showed that instability and laxity among grafts fromthe flexor tendons occurred because of the fixation methodsused, and that if methods that were more effective were used,the results were similar to those using grafts from the patellartendon.
In the present study, it was decided to fix the grafts fromthe patellar and flexor tendons, both in the tibial and in thefemoral tunnel, using an absorbable interference screw, sincethis has been shown to present excellent fixation results, withadequate stiffness.
In addition to good fixation, the objective nowadays is toachieve anatomical reconstruction of the ACL, so as to reestab-lish the structural and biomechanical properties of the knee,7,8especially in relation to rotational instability.8Recent studieshave compared anatomic ACL reconstruction using a doubleband and a single band.7,23According to Misonoo et al.,7thereare no statistical differences regarding rotational stability. Inthe present study, it was decided to perform anatomical recon-struction using a single band, since the technique presentslower complexity and lower cost and it facilitates possiblerevisions.
The present study did not present any statistically signif-icant difference in comparative analysis between grafts fromthe patellar and flexor tendons, as observed using the Lysholmmethod, which subjectively evaluates knee function and pro-duced excellent results at the end of the sixth month. Thisresult has also been seen in other published studies.
As also observed by other authors, no difference in graftuse was observed when this was assessed using the IKDCscale.
In 2003, Jansson et al.27conducted a prospective random-ized study on 89 patients who were followed up for 21 months,in which they observed that ACL reconstruction using thepatellar tendon presented limitation of extension during thefirst year and became normal by the end of this period. Gold-blatt et al.28demonstrated in 2005 that patients in whom thepatellar tendon was used as a graft presented greater exten-sion deficits (5?or more), while those in whom the flexortendons were used presented flexion deficits of 5?or more. In2007, in a prospective study, Laxdal et al.26did not observe anystatistically significant difference in range of motion betweenthe groups studied, as also seen in the present study.
Some studies have shown that patients present greatercomplaints of pain in the anterior region of the knee, particu-larly when kneeling down, when the patellar tendon is used asa graft.9,25,27In a study by Vasconcelos et al.,25among patientsin whom grafts from the flexor tendons were used, the com-plaints of pain were mainly from the medial region.25However, other studies have reported that there was no statistical dif-ference in knee pain between the grafts used,15,18in the sameway as seen in the results from the present study.
Overall, the ligament evaluations in knees that underwentACL reconstruction did not show any statistical differencesbetween the groups observed, either in our study or inothers.15,27,29Using the anterior drawer test alone to evalu-ate the reconstructed tendon, it was observed over the firstthree postoperative months that the anterior translation of thetibia at flexion of 90?was greater in the group in which flexortendons were used. After six months of evaluation, there wasno difference between the groups.22In the Lachman test, bet-ter results were observed in the third and sixth months afterthe operation, in the patients in whom the ligament recon-struction was performed using the patellar tendon. This resultdiffered from what was observed in the study by Pinczewskiet al.,24in which no difference between the groups after 10years of follow-up.
The present study can be criticized in terms of the smallnumber of patients selected (n = 27), the short length of follow-up, the greater proportion of male patients, the absence ofstatistical evaluation on associated lesions and the lack ofarthrometer for greater precision of evaluation on the recon-structed ligament.
Conclusion
According to the Lysholm functional evaluation and the IKDCsubjective assessment, there was no statistically significantdifference in the results between the groups. It is suggestedthat in future studies, associated lesions should be evaluated,with longer follow-up and use of an arthrometer for assess-ments of greater precision.
Conflicts of interest
The authors declare no conflicts of interest.
1. Fukubayashi T, Torzilli PA, Sherman MF, Warren RF. Anin vitro biomechanical evaluation of anterior-posteriormotion of the knee. Tibial displacement, rotation, and torque.J Bone Joint Surg Am. 1982;64(2):258-64.2. Busfield BT, Safran MR, Cannon WD. Extensor mechanismdisruption after contralateral middle third patellar tendonharvest for anterior cruciate ligament revisionreconstruction. Arthroscopy. 2005;21(10):1268.3. Lyman S, Koulouvaris P, Sherman S, Do H, Mandl LA, Marx RG.Epidemiology of anterior cruciate ligament reconstruction:trends, readmissions, and subsequent knee surgery. J BoneJoint Surg Am. 2009;91(10):2321-8.4. Campbell WC. Reconstruction of the ligaments of the knee.Am J Surg. 1939;43:473-80.5. Macey BH. A new operative procedure for repair of rupturedcruciate ligaments of the knee joint. Surg Gynecol Obstet.1939;69:108-9.6. Kopf S, Martin DE, Tashman S, Fu FH. Effect of tibial drillangles on bone tunnel aperture during anterior cruciateligament reconstruction. J Bone Joint Surg Am.2010;92(4):871-81.7. Misonoo G, Kanamori A, Ida H, Miyakawa S, Ochiai N.Evaluation of tibial rotational stability of single-bundle vs.anatomical double-bundle anteriorcruciate ligamentreconstruction during a high-demand activity - aquasi-randomized trial. Knee. 2012;19(2):87-93.8. Steiner M. Anatomic single-bundle ACL reconstruction.Sports Med Arthrosc. 2009;17(4):247-51.9. Shaieb MD, Kan DM, Chang SK, Marumoto JM, Richardson AB.A prospective randomized comparison of patellar tendonversus semitendinosous and gracilis tendon autografts foranterior cruciate ligament reconstruction. Am J Sports Med.2002;30(2):214-20.10. Metsavaht L, Leporace G, Riberto M, de Mello Sposito MM,Batista LA. Translation and cross-cultural adaptation of theBrazilian version of the International Knee DocumentationCommittee Subjective Knee Form: validity andreproducibility. Am J Sports Med. 2010;38(9):1894-9.11. Peccin MS, Ciconelli R, Cohen M. Questionário específico parasintomas do joelho Lysholm Knee Scoring Scale: traduc¸ão evalidac¸ão para a língua portuguesa. Acta Ortop Bras.2006;14(5):268-72.12. Garofalo R, Mouhsine E, Chambat P, Siegrist O. Anatomicanterior cruciate ligament reconstruction: the two-incisiontechnique. Knee Surg Sports Traumatol Arthrosc.2006;14(6):510-6.13. Harilainen A, Linko E, Sandelin J. Randomized prospectivestudy of ACL reconstruction with interference screw fixationin patellar tendon autografts versus femoral metal platesuspension and tibial post fixation in hamstring tendonautografts: 5-year clinical and radiological follow-up results.Knee Surg Sports Traumatol Arthrosc. 2006;14(6):517-28.14. Shelbourne KD, Gray T. Results of anterior cruciate ligamentreconstruction based on meniscus and articular cartilagestatus at the time of surgery. Five- to fifteen-year evaluations.Am J Sports Med. 2000;28(4):446-52.15. Eriksson K, Anderberg P, Hamberg P, Löfgren AC, BredenbergM, Westman I, et al. A comparison of quadruplesemitendinosus and patellar tendon grafts in reconstructionof the anterior cruciate ligament. J Bone Joint Surg Br.2001;83(3):348-54.16. Prodromos CC, Joyce BT, Shi K, Keller BL. A meta-analysis ofstability after anterior cruciate ligament reconstruction as afunction of hamstring versus patellar tendon graft andfixation type. Arthroscopy. 2005;21(10):1202.17. Milano G, Mulas PD, Ziranu F, Piras S, Manunta A, FabbricianiC. Comparison between different femoral fixation devices forACL reconstruction with doubled hamstring tendon graft: abiomechanical analysis. Arthroscopy. 2006;22(6):660-8.18. Biau DJ, Tournoux C, Katsahian S, Schranz PJ, Nizard RS.Bone-patellar tendon-bone autografts versus hamstringautografts for reconstruction of anterior cruciate ligament:meta-analysis. BMJ. 2006;332(7548):995-1001.19. Kousa P, Järvinen TL, Kannus P, Järvinen M. Initial fixationstrength of bioabsorbable and titanium interference screws inanterior cruciate ligament reconstruction. Biomechanicalevaluation by single cycle and cyclic loading. Am J SportsMed. 2001;29(4):420-5.20. Radford MJ, Noakes J, Read J, Wood DG. The natural history ofa bioabsorbable interference screw used for anterior cruciateligament reconstruction with a 4-strand hamstringtechnique. Arthroscopy. 2005;21(6):707-10.21. Brand JC Jr, Nyland J, Caborn DN, Johnson DL. Soft-tissueinterference fixation: bioabsorbable screw versus metalscrew. Arthroscopy. 2005;21(8):911-6.22. Maletis GB, Cameron SL, Tengan JJ, Burchette RJ. Aprospective randomized study of anterior cruciate ligament reconstruction: a comparison of patellar tendon andquadruple-strand semitendinosus/gracilis tendons fixed withbioabsorbable interference screws. Am J Sports Med.2007;35(3):384-94.23. Ferretti A, Monaco E, Labianca L, De Carli A, Maestri B,Conteduca F. Double-bundle anterior cruciate ligamentreconstruction: a comprehensive kinematic study usingnavigation. Am J Sports Med. 2009;37(8):1548-53.24. Pinczewski LA, Lyman J, Salmon LJ, Russell VJ, Roe J, LinklaterJ. A 10-year comparison of anterior cruciate ligamentreconstructions with hamstring tendon and patellar tendonautograft: a controlled, prospective trial. Am J Sports Med.2007;35(4):564-74.25. Vasconcelos W, Santos C, Ferracini AM, Dejour D. Influence ofanterior pain on results from anterior cruciate ligamentreconstruction. Rev Bras Ortop. 2011;46(1):40-4.26. Laxdal G, Sernert N, Ejerhed L, Karlsson J, Kartus JT. Aprospective comparison of bone-patellar tendon-bone andhamstring tendon grafts for anterior cruciate ligamentreconstruction in male patients. Knee Surg Sports TraumatolArthrosc. 2007;15(2):115-25.27. Jansson KA, Linko E, Sandelin J, Harilainen A. A prospectiverandomized study of patellar versus hamstring tendonautografts for anterior cruciate ligament reconstruction. Am JSports Med. 2003;31(1):12-8.28. Goldblatt JP, Fitzsimmons SE, Balk E, Richmond JC.Reconstruction of the anterior cruciate ligament:meta-analysis of patellar tendon versus hamstring tendonautograft. Arthroscopy. 2005;21(7):791-803.29. O'Neill DB. Arthroscopically assisted reconstruction of theanterior cruciate ligament. A prospective randomizedanalysis of three techniques. J Bone Joint Surg Am.1996;78(6):803-13.
