Comparable results between lateralized single- and double-bundle ACL reconstructions

Restoring Knee Flexor Strength Symmetry Requires 2 Years After ACL Reconstruction, But Does It Matter for Second ACL Injuries? A Systematic Review and Meta-analysis

BACKGROUND

It is unknown whether knee flexor strength recovers after anterior cruciate ligament (ACL) reconstruction with a hamstring tendon (HT) autograft and whether persistent knee flexor strength asymmetry is associated to a second ACL injury.

OBJECTIVE

We aimed to systematically review (1) whether knee flexor strength recovers after ACL reconstruction with HT autografts, and (2) whether it influences the association with a second ACL injury. A third aim was to summarize the methodology used to assess knee flexor strength.

DESIGN

Systematic review and meta-analysis reported according to PRISMA.

METHODS

A systematic search was performed using the Cochrane Library, Embase, Medline, PEDRo, and AMED databases from inception to December 2021 and until completion in January 2023. Human clinical trials written in English and conducted as randomized controlled trials, longitudinal cohort, cross-sectional, and case-control studies on patients with index ACL reconstructions with HT autografts harvested from the ipsilateral side were considered. Knee flexor strength was measured isokinetically in both the reconstructed and uninjured limb to enable the calculation of the limb symmetry index (LSI). The Risk of Bias Assessment Tool for Non-Randomized Studies was used to assess risk of bias for non-randomized studies and the revised Cochrane Risk of Bias tool was used for randomized controlled trials. For the meta-analysis, the LSI (mean ± standard error) for concentric knee flexor strength at angular velocities of 60°/second (s) and 180°/s preoperatively and at 3 months, 6 months, 12 months, and 24 months were pooled as weighted means with standard errors.

RESULTS

The search yielded 64 studies with a total of 8378 patients, which were included for the assessment of recovery of knee flexor strength LSI, and a total of 610 patients from four studies that investigated the association between knee flexor strength and second ACL injuries. At 1 year after ACL reconstruction, the knee flexor strength LSI had recovered to 89.0% (95% CI 87.3; 90.7%) and 88.3% (95% CI 85.5; 91.1%) for the velocities of 60°/s and 180°/s, respectively. At 2 years, the LSI was 91.7% (95% CI 90.8; 92.6%) and 91.2% (95% CI 88.1; 94.2%), for velocities of 60°/s and 180°/s, respectively. For the association between knee flexor strength and second ACL injuries, there was insufficient and contradictory data.

CONCLUSIONS

There was low to very low certainty of evidence indicating that the recovery of knee flexor strength LSI, defined as ≥ 90% of the uninjured side, takes up to 2 years after ACL reconstruction with HT autografts. Whether knee flexor strength deficits influence the association of second ACL injuries is still uncertain. There was considerable heterogeneity in the methodology used for knee flexor strength assessment, which together with the low to very low certainty of evidence, warrants further caution in the interpretation of our results.

REGISTRATION NUMBER

CRD42022286773.

Higher Rates of Residual Postoperative Instability after Anterior Cruciate Ligament Reconstruction in Female Patients: A Systematic Review of Level II Studies

PURPOSE

To compare revision rates and residual postoperative instability after anterior cruciate ligament (ACL) reconstruction based on biological sex.

METHODS

A systematic review was conducted according to the 2020 PRISMA guidelines. PubMed, Embase, MEDLINE, and Cochrane library databases were queried from database inception through October 2022. Level I and II prospectively-enrolling human clinical studies that compared revision rates and physical examination of postoperative stability after ACL reconstruction between male and female patients were included. Outcomes were stratified by patient sex and quantitatively compared using a χ2 test. Study quality was assessed using the MINORS criteria.

RESULTS

Four studies consisting of 406 patients (50% males) with a mean age of 25 years (range, 13.9-62 years) were identified. Mean follow-up time was 34.4 months (range, 22-60 months). Hamstring tendon autografts were used in 62% of ACL reconstructions in males and in 65% of ACL reconstructions in females, whereas bone-patellar tendon-bone autografts were used in 38% and 35% of procedures in males and females, respectively. A residual positive Lachman test result was more frequently reported among females compared to males (5.8% vs 0.6%; P = 0.03). No significant difference in revision rates or residual pivot-shift on examination was observed between males and females (P = 0.38 and P = 0.08, respectively).

CONCLUSION

Female patients undergoing ACL reconstruction have higher reported rates of residual anterior instability with Lachman than male patients. However, no sex-based differences were identified with residual pivot-shift on examination or rate of revision ACL surgery.

LEVEL OF EVIDENCE

II; Systematic Review of level II studies.

Incidence and Risk Factors of Subsequent Meniscal Surgery After Successful Anterior Cruciate Ligament Reconstruction: A Retrospective Study With a Minimum 2-Year Follow-up

BACKGROUND

One of the goals of anterior cruciate ligament (ACL) reconstruction is a meniscal protective effect on the knee. Despite the advancement of ACL reconstruction techniques, subsequent meniscal tears after ACL reconstruction remain a problem, and the risk factors for recurring lesions are still unclear.

PURPOSE

To investigate the incidence of subsequent meniscal surgery after primary ACL reconstruction without revision ACL surgery and to determine the risk factors associated with this reoperation.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Overall, 518 patients who underwent primary ACL reconstruction between 2004 and 2012 at one instution participated in this study. Data on body mass index, graft type and femoral tunnel-drilling technique of ACL reconstruction, and location and type of meniscal injury and its treatment at ACL reconstruction were collected from medical records. Clinical outcomes were investigated, including side-to-side difference of anterior laxity, pivot-shift grade, and subsequent meniscal surgery without ACL insufficiency (at minimum 2-year follow-up).

RESULTS

The prevalence of tears to the medial meniscus (MM) at the primary ACL reconstruction was 43.6% (226/518), 140 of which were repaired; on the contrary, tears of the lateral meniscus (LM) had a prevalence of 55.8% (289/518), 42 of which were repaired. At a mean 30.3 months (range, 8-124 months) after ACL reconstruction, 20 patients (3.9%; 14 MM tears, 3 LM tears, 3 MM + LM tears) required meniscal surgery without ACL reinjury or recurrence of instability. Of these, 14 MMs and 3 LMs had been repaired at primary ACL reconstruction. The failure rates of repaired MM and LM were 10.0% (14/140) and 7.1% (3/42), respectively. The failure rate of MM repair using the all-inside technique (6/36) was significantly higher compared with no treatment, inside-out repair, or partial resection (P = .045). In multiple regression analysis, the presence of MM injury at the time of ACL reconstruction (odds ratio [OR], 7.81; P = .003), the side-to-side difference of postoperative anterior tibial translation (OR, 1.91; P = .032), and follow-up period after ACL reconstruction (OR, 1.02; P = .003) were risk factors of subsequent meniscal surgery after ACL reconstruction.

CONCLUSION

Incidence of subsequent meniscal surgery after successful ACL reconstruction was <5%. Presence of MM tear at the time of ACL reconsturuction, small amount of increased anterior laxity, and long-term period after ACL reconstruction were predictive of subsequent meniscal surgery.

[Ligamentoplasty of the anterior cruciate ligament of the knee-joint in the athlete: retrospective study of 80 cases conducted in the Department of Orthopaedics in Tataouine, Tunisia]

La ligamentoplastie du ligament croisé antérieur a pour but de corriger la laxité antérieure du genou afin de retrouver une stabilité et une indolence. Le but de notre travail est d'évaluer les résultats fonctionnels à court et à moyen terme de notre série. C'est une étude rétrospective réalisée au service de Traumato-Orthopédie de l'hôpital de Tataouine au Sud tunisien, étalée sur une période de 5 ans, allant du mois de janvier 2013 au mois d'avril 2018, concernant 80 sportifs tous présentant une laxité chronique du genou secondaire à une rupture du LCA suite à un accident sportif. Tous les patients ont été opérés par le même chirurgien sous arthroscopie, le transplant a été prélevé soit du tendon rotulien soit des tendons de la patte d'oie. L'évaluation fonctionnelle a été faite selon le score fonctionnel de Lyshlom-Tegner. Dans notre étude, la reconstruction du LCA par le tendon rotulien a été pratiquée chez 20 patients, et par les tendons de la patte d'oie pour 60 patients. Le délai moyen de la reprise du sport dans notre série était de 9 mois. L'échelle de l'activité de Tegner a montré que 65 patients ont repris le sport au même niveau, avec un délai moyen de 9 mois, avec une reprise du sport à un niveau inférieur pour le reste. La ligamentoplastie du ligament croisé antérieur sous arthroscopie avec une maîtrise de la technique et une rééducation post opératoire donnent des résultats fonctionnels satisfaisants avec reprise de l'activité sportive.

Biomechanical comparison of single-bundle versus double-bundle anterior cruciate ligament reconstruction: a meta-analysis

BACKGROUND

Of the many issues regarding surgical techniques related to anterior cruciate ligament reconstruction (ACLR), single-bundle (SB) or double-bundle (DB) ACLR is one of the most debated topics. However, it is unclear which of the techniques yields better outcomes after ACLR for ACL injury. The purpose of this meta-analysis was to compare the benefits of SB versus DB ACLR in terms of biomechanical outcomes.

METHODS

The electronic databases MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and Scopus were searched for relevant articles comparing the outcomes of SB-ACLR versus DB-ACLR that were published until November 2019.

RESULTS

Seventeen biomechanical studies were included. The anterior laxity measured using the anterior drawer test showed significantly better results in DB-ACLR when compared with SB-ACLR. In addition, outcomes of the anterior tibial translation test under a simulated pivot shift presented with better results at low flexion and 30° in DB-ACLR, compared with SB-ACLR. However, there were no significant biomechanical differences between the groups in internal rotation.

CONCLUSIONS

The present study demonstrated that both techniques for ACLR are associated with restoration of normal knee kinematics. DB-ACLR is superior to SB-ACLR in terms of restoration of anteroposterior stability. However, which technique yields better improvement in internal rotation laxity, and internal rotation laxity under a simulated pivot shift at a specific angle, remains unclear.

LEVEL OF EVIDENCE

This is a level II meta-analysis.

Changes in inflammatory factors in patients with osteoporotic vertebral compression fracture and influences of rehabilitation training on postoperative functional recovery and inflammation

OBJECTIVE

To observe the changes in inflammatory factors in patients with osteoporotic vertebral compression fracture (OVCF).

METHODS

40 OVCF patients meeting inclusion criteria were collected, and randomly divided into rehabilitation therapy group (n=20) and traditional therapy group (n=20). 20 normal subjects were collected as control group. Venous blood was collected after admission, and the expression levels of IL-1 and IL-18 were detected via ELISA. Patients in rehabilitation therapy group received rehabilitation training post-operatively, while those in traditional therapy group received conventional therapy. The pain was evaluated using visual analogue scale (VAS) score, and the spinal function was evaluated using Oswestry disability index (ODI) score. The curative effect was evaluated at final follow-up.

RESULTS

The expression levels of IL-1 and IL-18 of OVCF patients were significantly higher than those in normal subjects (p<0.01). The VAS and ODI scores in the rehabilitation therapy group were significantly lower than those in traditional therapy group from the 3rd month after operation (p<0.05). The expression levels of IL-1 and IL-18 in the rehabilitation therapy group were obviously lower than those in traditional therapy group from the 3rd month after operation (p<0.05). The effective rate in rehabilitation therapy group was higher than that in traditional therapy group. The expression levels of IL-1 and IL-18 in OVCF patients are increased.

CONCLUSION

Rehabilitation training is beneficial to functional recovery and reduction of inflammation after OVCF operation.

Anterolateral rotatory instability in vivo correlates tunnel position after anterior cruciate ligament reconstruction using bone-patellar tendon-bone graft

AIM

To quantitatively assess rotatory and anterior-posterior instability in vivo after anterior cruciate ligament (ACL) reconstruction using bone-patellar tendon-bone (BTB) autografts, and to clarify the influence of tunnel positions on the knee stability.

METHODS

Single-bundle ACL reconstruction with BTB autograft was performed on 50 patients with a mean age of 28 years using the trans-tibial (TT) (n = 20) and trans-portal (TP) (n = 30) techniques. Femoral and tibial tunnel positions were identified from the high-resolution 3D-CT bone models two weeks after surgery. Anterolateral rotatory translation was examined using a Slocum anterolateral rotatory instability test in open magnetic resonance imaging (MRI) 1.0-1.5 years after surgery, by measuring anterior tibial translation at the medial and lateral compartments on its sagittal images. Anterior-posterior stability was evaluated with a Kneelax3 arthrometer.

RESULTS

A total of 40 patients (80%) were finally followed up. Femoral tunnel positions were shallower (P < 0.01) and higher (P < 0.001), and tibial tunnel positions were more posterior (P < 0.05) in the TT group compared with the TP group. Anterolateral rotatory translations in reconstructed knees were significantly correlated with the shallow femoral tunnel positions (R = 0.42, P < 0.01), and the rotatory translations were greater in the TT group (3.2 ± 1.6 mm) than in the TP group (2.0 ± 1.8 mm) (P < 0.05). Side-to-side differences of Kneelax3 arthrometer were 1.5 ± 1.3 mm in the TT, and 1.7 ± 1.6 mm in the TP group (N.S.). Lysholm scores, KOOS subscales and re-injury rate showed no difference between the two groups.

CONCLUSION

Anterolateral rotatory instability significantly correlated shallow femoral tunnel positions after ACL reconstruction using BTB autografts. Clinical outcomes, rotatory and anterior-posterior stability were overall satisfactory in both techniques, but the TT technique located femoral tunnels in shallower and higher positions, and tibial tunnels in more posterior positions than the TP technique, thus increased the anterolateral rotation. Anatomic ACL reconstruction with BTB autografts may restore knee function and stability.

The evolution of primary double-bundle ACL reconstruction and recovery of early post-operative range of motion

PURPOSE

The aim of this study was to analyse early post-operative range of motion (ROM) as our anatomic double-bundle (DB) anterior cruciate (ACL) reconstruction technique with respect to tunnel placement evolved. It is the hypothesis of this study that more anatomic placement of the femoral insertion site of the anteromedial (AM) bundle of the ACL results in better restoration of early post-operative knee range of motion.

METHODS

Two methods of DB ACL reconstruction regarding more accurate placement of the femoral AM tunnel in relation to its anatomic origin were compared. Patients presenting for 1- and 3-month post-operative clinical visits were examined for passive extension and active flexion by members of the clinical staff. Only patients undergoing primary DB reconstruction with allograft were included in the analyses. To determine the effects of the modified AM bundle placement on recovery of post-operative ROM, patients undergoing surgery in the 6 months before July 2006 (Group A, n = 50) were compared to patients undergoing surgery in the 6 months after July 2006 (Group B, n = 49).

RESULTS

A total of 99 patients met the inclusion criteria. More accurate placement of the AM bundle of the ACL was associated with a smaller side-to-side difference in flexion at 1 month (n.s.) and at 3 months (3° reduction, p < 0.03) after surgery. There was no effect on extension (n.s.) CONCLUSION: More anatomic placement of the femoral insertion of the AM bundle was associated with improved knee flexion. The study translates the findings of previous anatomic basic science research to demonstrate improved restoration of normal joint motion. This ideally leads to improved long-term clinical outcomes and maintenance of joint and cartilage health.

LEVEL OF EVIDENCE

III.

Prospective Randomized Study of Objective and Subjective Clinical Results Between Double-Bundle and Single-Bundle Anterior Cruciate Ligament Reconstruction

BACKGROUND

There is controversy as to whether double-bundle anterior cruciate ligament (ACL) reconstruction with hamstring tendon graft (DB-HT) or single-bundle ACL reconstruction with patellar tendon graft (SB-PT) obtains the best clinical outcomes.

PURPOSE

To compare the short-term clinical outcomes of DB-HT with those of rectangular-tunnel SB-PT (RTSB-PT) at 2-year follow-up and to identify the factors that affect subjective knee functional score.

STUDY DESIGN

Randomized controlled trial. Level of evidence, 1.

METHODS

Sixty-three male patients (mean age, 26.1 years) and 87 female patients (mean age, 25.8 years) were included in this study and were randomly distributed to either the DB-HT (n = 76) or RTSB-PT (n = 74) group. Clinical outcomes (knee flexion range of motion [ROM], heel-height difference, side-to-side difference in anterior laxity, rotational laxity, and Tegner activity score) were compared between the DB-HT and RTSB-PT groups, and examination of factors affecting subjective outcomes (Knee Injury and Osteoarthritis and Outcome Score [KOOS] results) was performed by multiple linear regression analysis.

RESULTS

Fourteen patients (9 DB-HT, 5 RTSB-PT) had secondary ACL injury within 2 years after primary ACL reconstruction and were excluded from analysis. In the examination of 136 patients at the 24-month follow-up, there was no significant difference between the 2 groups in clinical or subjective outcomes. The normalized knee extensor strength of the RTSB-PT group showed negative surgical technique effect in the early postoperative phase (P = .005), but there was no significant difference between the 2 groups at the 24-month follow-up (P = .114). There was no significant difference in change of normalized knee flexor strength between the 2 groups (P = .493). Age, sex, body mass index (BMI), and presence of meniscus injury were the factors that affected KOOS subscale scores.

CONCLUSION

In this prospective randomized controlled study, there was no significant difference in the incidence of secondary ACL injury and no difference in objective or subjective outcomes between the DB-HT and RTSB-PT reconstruction at 24-month follow-up. Age, sex, presence of meniscus injury, and BMI affected subjective KOOS subscale scores, while surgical technique did not.

A systematic review of single- versus double-bundle ACL reconstruction using the anatomic anterior cruciate ligament reconstruction scoring checklist

PURPOSE

The aim of this systematic review was to apply the anatomic ACL reconstruction scoring checklist (AARSC) and to evaluate the degree to which clinical studies comparing single-bundle (SB) and double-bundle (DB) ACL reconstructions are anatomic.

METHODS

A systematic electronic search was performed using the databases PubMed (MEDLINE), EMBASE and Cochrane Library. Studies published from January 1995 to January 2014 comparing SB and DB ACL reconstructions with clinical outcome measurements were included. The items from the AARSC were recorded for both the SB and DB groups in each study.

RESULTS

Eight-thousand nine-hundred and ninety-four studies were analysed, 77 were included. Randomized clinical trials (29; 38%) and prospective comparative studies (29; 38%) were the most frequent study type. Most studies were published in 2011 (19; 25%). The most commonly reported items for both SB and DB groups were as follows: graft type (152; 99%), femoral and tibial fixation method (149; 97% respectively), knee flexion angle during graft tensioning (124; 8%) and placement of the tibial tunnel at the ACL insertion site (101; 66%). The highest level of documentation used for ACL tunnel position for both groups was often one dimensional, e.g. drawing, operative notes or o'clock reference. The DB reconstruction was in general more thoroughly reported. The means for the AARSC were 6.9 ± 2.8 for the SB group and 8.3 ± 2.8 for the DB group. Both means were below a proposed required minimum score of 10 for anatomic ACL reconstruction.

CONCLUSIONS

There was substantial underreporting of surgical data for both the SB and DB groups in clinical studies. This underreporting creates difficulties when analysing, comparing and pooling results of scientific studies on this subject.

The Importance of Patient Sex in the Outcomes of Anterior Cruciate Ligament Reconstructions: A Systematic Review and Meta-analysis

BACKGROUND

One of the well-studied epidemiological phenomena of anterior cruciate ligament (ACL) injuries is the 2- to 9-fold increase in the relative risk of ACL rupture in female athletes compared with male athletes. However, the influence of patient sex on the outcome after ACL reconstruction remains unclear, with some authors reporting inferior outcomes in females and others noting no significant difference.

PURPOSE

To provide a comprehensive systematic review and meta-analysis to examine the possible association between patient sex and the subjective and objective outcomes after ACL reconstruction.

METHODS

This study was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. All studies that reported clinical outcomes after ACL reconstruction in males and females independently were included in the review. A quantitative random-effects meta-analysis was performed to compare outcomes between sexes. For outcomes with considerable heterogeneity, meta-regression was used to identify potential moderators. Articles were evaluated qualitatively when quantitative data were not reported.

RESULTS

A total of 135 publications were included in the review. Females had inferior outcomes in instrumented laxity (standardized mean difference [SMD], 0.24; 95% CI, 0.11-0.37), revision rate (relative risk [RR], 1.15; 95% CI, 1.02-1.28), Lysholm score (SMD, -0.33; 95% CI, -0.55 to -0.11), Tegner activity scale (SMD, -0.37; 95% CI, -0.49 to -0.24), and incidence of not returning to sports (RR, 1.12; 95% CI, 1.04-1.21), all of which were statistically significant. Other outcomes were comparable between sexes, including anterior drawer test, Lachman test, pivot-shift test, timed single-legged hop test, single-legged hop test, quadriceps testing, hamstring testing, extension loss, flexion loss, development of cyclops lesion, and International Knee Documentation Committee (IKDC) knee examination score. Females and males were equally likely to develop anterior knee pain and osteoarthritis after ACL reconstruction. The graft rupture and graft failure rates did not differ significantly between sexes.

CONCLUSION

There were comparable or inferior results for females compared with males in all outcomes analyzed. No statistically significant sex difference was identified in most of the objective parameters. However, subjective and functional outcomes, including Lysholm score, Tegner activity scale, and ability to return to sports, have been shown to be poorer in females.

Single-bundle modified patellar tendon versus double-bundle tibialis anterior allograft ACL reconstruction: a prospective randomized study

PURPOSE

The purpose of this study was to prospectively compare the outcomes of single-bundle (SB) anterior cruciate ligament (ACL) reconstruction with modified bone-patellar tendon-bone (BPTB) allograft and double-bundle (DB) reconstruction with tibialis anterior allograft.

METHODS

With 94 patients enroled in the study, 43 subjects who had SB ACL reconstruction with modified BPTB allograft (group S) and 41 subjects of DB ACL reconstruction with tibialis anterior allograft (group D) were followed up for a minimum of 2 years. Clinical outcomes including Lachman and pivot-shift tests, KT-1000 arthrometer measurements, and the International Knee Documentation Committee (IKDC) classification, Lysholm and Tegner activity scores were compared between the two groups at the last follow-up.

RESULTS

The mean graft size of the group S, the anteromedial bundle and posterolateral bundle in group D were 9.9 ± 0.2, 7.5 ± 0.4 and 6.6 ± 0.4 mm, with statistically significant difference between the group S graft to either bundle of group D grafts (p < 0.001). At the last follow-up, there was no statistical difference between the two groups for the Lachman test, pivot-shift test and side-to-side difference. Substantial improvements in the subjective knee function scores were achieved in both groups, but without significant difference between the two groups.

CONCLUSIONS

After a 2-year minimum follow-up, SB ACL reconstruction based on modified BPTB allograft achieved similar clinical outcomes to DB reconstruction with tibialis anterior allograft in knee stability, both anterior-posterior and rotational, as well as knee function. The modified BPTB allograft was recommended as an ideal graft option for the SB ACL reconstruction.

LEVEL OF EVIDENCE

Therapeutic, randomized controlled study, Level II.

Dynamic Effect of Quadriceps Muscle Activation on Anterior Tibial Translation After Single-Bundle and Double-Bundle Anterior Cruciate Ligament Reconstruction

PURPOSE

To examine differences in anterior tibial translation in 3 groups: single-bundle anterior cruciate ligament (ACL)-reconstructed, double-bundle ACL-reconstructed, and ACL-intact knees under gradual dynamic quadriceps muscle activation.

METHODS

Thirty male patients underwent successful single-bundle (n = 15) and double-bundle (n = 15) ACL reconstructions; 15 healthy controls were included in the study. Anterior tibial translation was assessed at 30° of knee flexion in the resting position (0% quadriceps activation) and under 50% and 100% of maximum quadriceps concentric contraction using an isokinetic dynamometer with the KT-2000 arthrometer securely attached to the participants' knees.

RESULTS

The 2 ACL-reconstructed groups were similar regarding International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Score (KOOS), Tegner, and Lysholm scores and preliminary isokinetic evaluation (P = .38). Quadriceps activation significantly affected anterior tibial translation (P = .001, α = 0.98). In all 3 study groups, anterior tibial translation was significantly higher under 100% quadriceps activation compared with 0% contraction (P = .01) and 50% quadriceps activation (P = .047). There were no between-group differences in anterior tibial translation with 0%, 50%, or 100% quadriceps activation (P = .46).

CONCLUSIONS

Under quadriceps muscle activation, anteroposterior knee laxity in ACL-intact and ACL-reconstructed knees is gradually increased. Single-bundle and double-bundle ACL-reconstructed knees show a similar increase in anterior tibial translation under gradual quadriceps contraction. When comparing different ACL reconstruction techniques in the experimental setting, dynamic, in addition to static, testing is advised to reach a comprehensive assessment of anteroposterior knee stability.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Kinematic Analysis of Five Different Anterior Cruciate Ligament Reconstruction Techniques

Several anatomical anterior cruciate ligament (ACL) reconstruction techniques have been proposed to restore normal joint kinematics. However, the relative superiorities of these techniques with one another and traditional single-bundle reconstructions are unclear. Kinematic responses of five previously reported reconstruction techniques (single-bundle reconstruction using a bone-patellar tendon-bone graft [SBR-BPTB], single-bundle reconstruction using a hamstring tendon graft [SBR-HST], single-tunnel double-bundle reconstruction using a hamstring tendon graft [STDBR-HST], anatomical single-tunnel reconstruction using a hamstring tendon graft [ASTR-HST], and a double-tunnel double-bundle reconstruction using a hamstring tendon graft [DBR-HST]) were systematically analyzed. The knee kinematics were determined under anterior tibial load (134 N) and simulated quadriceps load (400 N) at 0°, 15°, 30°, 60°, and 90° of flexion using a robotic testing system. Anterior joint stability under anterior tibial load was qualified as normal for ASTR-HST and DBR-HST and nearly normal for SBR-BPTB, SBR-HST, and STDBR-HST as per the International Knee Documentation Committee knee examination form categorization. The analysis of this study also demonstrated that SBR-BPTB, STDBR-HST, ASTR-HST, and DBR-HST restored the anterior joint stability to normal condition while the SBR-HST resulted in a nearly normal anterior joint stability under the action of simulated quadriceps load. The medial-lateral translations were restored to normal level by all the reconstructions. The internal tibial rotations under the simulated muscle load were over-constrained by all the reconstruction techniques, and more so by the DBR-HST. All five ACL reconstruction techniques could provide either normal or nearly normal anterior joint stability; however, the techniques over-constrained internal tibial rotation under the simulated quadriceps load.

Does Double-Bundle Anterior Cruciate Ligament Reconstruction Improve Postoperative Knee Stability Compared With Single-Bundle Techniques? A Systematic Review of Overlapping Meta-analyses

PURPOSE

Multiple meta-analyses of randomized controlled trials, the highest available level of evidence, have been conducted to determine whether double-bundle (DB) or single-bundle (SB) anterior cruciate ligament reconstruction (ACL-R) provides superior clinical outcomes and knee stability; however, results are discordant. The purpose of this study was to conduct a systematic review of meta-analyses comparing SB and DB ACL-R to discern the cause of the discordance and to determine which of these meta-analyses provides the current best available evidence.

METHODS

We evaluated available scientific support for SB as compared with DB ACL-R by systematically reviewing the literature for published meta-analyses. Data on patient clinical outcomes and knee stability (as measured by KT arthrometry and pivot-shift testing) were extracted. Meta-analysis quality was judged using the Oxman-Guyatt and Quality of Reporting of Meta-analyses systems. The Jadad algorithm was then applied to determine which meta-analyses provided the highest level of evidence.

RESULTS

Nine meta-analyses were included, of which 3 included Level I Evidence and 6 included both Level I and Level II Evidence. Most studies found significant differences favoring DB reconstruction on pivot-shift testing, KT arthrometry measurement of anterior tibial translation, and International Knee Documentation Committee objective grading. Most studies detected no significant differences between the 2 techniques in subjective outcome scores (Tegner, Lysholm, and International Knee Documentation Committee subjective), graft failure, or complications. Oxman-Guyatt and Quality of Reporting of Meta-analyses scores varied, with 2 studies exhibiting major flaws (Oxman-Guyatt score <3). After application of the Jadad decision algorithm, 3 concordant high-quality meta-analyses were selected, with each concluding that DB ACL-R provided significantly better knee stability (by KT arthrometry and pivot-shift testing) than SB ACL-R but no advantages in clinical outcomes or risk of graft failure.

CONCLUSIONS

The current best available evidence suggests that DB ACL-R provides better postoperative knee stability than SB ACL-R, whereas clinical outcomes and risk of graft failure are similar between techniques.

LEVEL OF EVIDENCE

Level II, systematic review of Level I and II studies.

No difference in revision rates between single- and double-bundle anterior cruciate ligament reconstruction: a comparative study of 16,791 patients from the Swedish national knee ligament register

PURPOSE

The purpose was to compare revision rates and patient-reported outcomes between single- and double-bundle anterior cruciate ligament (ACL) reconstructions.

METHODS

All patients from the Swedish National Knee Ligament Register from 2005 through 2011 who underwent primary ACL reconstruction with hamstring autografts were included. Patients with concomitant injuries, except meniscal and chondral injuries, were excluded. By December 31, 2011, 16,791 primary isolated ACL reconstructions had been registered, of which 16,281 were single-bundle and 510 were double-bundle. Cumulative revision rates were estimated using Kaplan-Meier analysis. The Knee injury and Osteoarthritis Outcome Score (KOOS) and EQ-5D were calculated at 1- and 2-year follow-ups.

RESULTS

The revision rate showed no statistically significant differences between the groups (P = .30). Over the 7-year observation period, 347 single-bundle (2.1%) and 8 double-bundle (1.6%) ACL reconstructions were revised. No significant differences in the KOOS or EQ-5D were found between the groups postoperatively. In addition, there were no differences in postoperative improvements in the KOOS or EQ-5D at 1- and 2-year follow-ups.

CONCLUSIONS

Revision rates after single- and double-bundle ACL reconstructions were low. No differences were found in revision rates, KOOS, and EQ-5D between the 2 techniques.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Is double-bundle anterior cruciate ligament reconstruction superior to single-bundle? A comprehensive systematic review

PURPOSE

To describe current evidence on single- and double-bundle anterior cruciate ligament (ACL) reconstruction, in terms of differences in knee kinematics, functional outcomes, patient-reported outcomes and graft failures.

METHODS

An electronic search was made using PubMed (MEDLINE), EMBASE and Cochrane Library. Studies published from January 1995 to August 2011 were included, and an updated search was made in PubMed in July 2012. Therapeutic studies, level of evidence I-III, for isolated primary ACL tears written in English comparing single- and double-bundle reconstruction reporting clinical outcome were included. Quality appraisal based on Cochrane Collaboration's tool for assessing risk of bias was performed.

RESULTS

Of 7,154 potentially eligible studies, 60 papers were included (25 randomised controlled trials, 21 prospective comparative studies, 14 retrospective comparative studies), comprising 4,146 patients (2,072 single-bundle, 2,074 double-bundle). Minor differences were found between study types. An analysis of graft failures revealed fewer re-ruptures in double-bundle reconstruction than single-bundle, 19 and 44, respectively. Up to 45 % of the studies reported a superior outcome in double-bundle reconstruction in terms of antero-posterior laxity, measured with the Lachman, anterior drawer, KT-1000/2000 and navigation. Measurements of rotatory laxity revealed superior results in double-bundle reconstruction measured with pivot shift and navigation in 18/42 (8/15 anatomically reconstructed) and 9/20 studies, respectively. Patient-reported outcome measures and functional outcomes did not differ to a large extent; however, differences when identified were almost exclusively in favour of double-bundle reconstruction.

CONCLUSION

Based on current evidence, double-bundle reconstruction appears to have fewer re-ruptures and less antero-posterior and rotatory laxity. Furthermore, no differences were found in short-term patient-reported outcome measures or objective findings. However, detailed statistical analyses of the included studies divided into homogeneous groups are needed to avoid reporting bias and to confirm any statistical difference.

Volume and contact surface area analysis of bony tunnels in single and double bundle anterior cruciate ligament reconstruction using autograft tendons: in vivo three-dimensional imaging analysis

Background

Regarding reconstruction surgery of the anterior cruciate ligament (ACL), there is still a debate whether to perform a single bundle (SB) or double bundle (DB) reconstruction. The purpose of this study was to analyze and compare the volume and surface area of femoral and tibial tunnels during transtibial SB versus transportal DB ACL reconstruction.

Methods

A consecutive series of 26 patients who underwent trantibial SB ACL reconstruction and 27 patients with transportal DB ACL reconstruction using hamstring autograft from January 2010 to October 2010 were included in this study. Three-dimensional computed tomography (3D-CT) was taken within one week after operation. The CT bone images were segmented with use of Mimics software v14.0. The obtained digital images were then imported in the commercial package Geomagic Studio v10.0 and SketchUp Pro v8.0 for processing. The femoral and tibial tunnel lengths, diameters, volumes and surface areas were evaluated. A comparison between the two groups was performed using the independent-samples t-test. A p-value less than the significance value of 5% (p < 0.05) was considered statistically significant.

Results

Regarding femur tunnels, a significant difference was not found between the tunnel volume for SB technique (1,496.51 ± 396.72 mm³) and the total tunnel volume for DB technique (1,593.81 ± 469.42 mm³; p = 0.366). However, the total surface area for femoral tunnels was larger in DB technique (919.65 ± 201.79 mm²) compared to SB technique (810.02 ± 117.98 mm²; p = 0.004). For tibia tunnels, there was a significant difference between tunnel volume for the SB technique (2,070.43 ± 565.07 mm³) and the total tunnel volume for the DB technique (2,681.93 ± 668.09 mm³; p ≤ 0.001). The tibial tunnel surface area for the SB technique (958.84 ± 147.50 mm²) was smaller than the total tunnel surface area for the DB technique (1,493.31 ± 220.79 mm²; p ≤ 0.001).

Conclusions

Although the total femoral tunnel volume was similar between two techniques, the total surface area was larger in the DB technique. For the tibia, both total tunnel volume and the surface area were larger in DB technique.

Single-bundle or double-bundle for anterior cruciate ligament reconstruction: a meta-analysis

PURPOSE

To compare the clinical outcomes of anterior cruciate ligament (ACL) reconstruction with double-bundle and single-bundle techniques.

STUDY DESIGN

Meta-analysis

METHODS

We searched electronic databases including PubMed, Embase, Cochrane Central Register of Controlled Trials, and Google Scholar from 1966 to Jan 2012 to identify randomized controlled trials (RCTs) comparing clinical outcomes of anterior cruciate ligament (ACL) reconstruction with double-bundle and single-bundle techniques. Two reviewers independently extracted data and assessed trial quality. Meta-analysis was performed to pool results.

RESULTS

Nineteen RCTs were included with a total of 1686 patients. The pooled analysis across all studies showed that the double-bundle ACL reconstruction technique could have significantly better outcomes in rotational laxity, as assessed by the pivot-shift test, KT grading and IKDC grading than the single-bundle techniques. We found no evidence of a difference in function measured by IKDC scores, KT arthrometer, Lysholm knee, or Tegner activity scores and complications after operations between single and double-bundle ACL reconstruction groups.

CONCLUSION

Our meta-analysis demonstrated the superiority of double-bundle over single-bundle anterior cruciate ligament reconstruction. The double-bundle ACL reconstruction technique has better outcomes in rotational laxity (pivot-shift test, KT grading and IKDC grading). However, for functional recovery, there was no significant difference between single-bundle and double-bundle reconstruction techniques.

Single-bundle versus double-bundle anterior cruciate ligament reconstruction: assessment with vertical jump test

PURPOSE

The study was designed to compare the clinical results of traditional single-bundle (SB) anterior cruciate ligament (ACL) reconstruction with those of double-bundle (DB) ACL reconstruction.

METHODS

This study comprised 80 patients aged 18 to 45 years with an isolated ACL lesion: 40 patients underwent SB reconstruction, and 40 patients underwent DB reconstruction. Patients were assessed preoperatively with functional assessment including the International Knee Documentation Committee 2000 knee subjective form and visual analog scale, as well as physical examination (including the pivot-shift test and instrumented knee laxity measurement). Vertical jump assessment with the Optojump system (Microgate, Bolzano, Italy) has been introduced as a method to compare functional ability between the 2 surgical techniques. The same protocol was repeated 6 months, 12 months, and 2 years after surgery.

RESULTS

No statistically significant differences were noted between the groups concerning subjective evaluation, thigh girth difference, mean visual analog scale score, range of motion, and Lachman and anterior drawer tests (P = not significant). A statistically higher number of patients in the SB group showed a positive pivot-shift test and a higher side-to-side difference when measured with the KT-1000 arthrometer (MEDmetric, San Diego, CA) than in the DB group (P < .001). Better mean jumping performance results were reported in the DB group compared with the SB group (P < .001). The average performance results for the injured limb were not significantly reduced compared with those of the uninjured limb in the DB group 12 months after surgery. At 2 years, a restoration of jumping ability in the ACL-reconstructed limb was achieved in both groups regardless of the technique used.

CONCLUSIONS

DB ACL reconstruction has been proven to be superior to the SB technique with regard to knee stability and vertical jump performance.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

Double-bundle versus single-bundle anterior cruciate ligament reconstructions: a prospective, randomized study with 2-year follow-up

This prospective, randomized study was conducted to compare the short-term results of arthroscopic double-bundle with single-bundle anterior cruciate ligament (ACL) reconstruction. One hundred and eight patients with a symptomatic ACL rupture were randomized to either double-bundle (Group DB) or single-bundle (Group SB) ACL reconstruction. Follow-up was conducted at 6, 12, 18 and 24 months postoperatively. At the 24-month follow-up, 94 of the 108 patients (87%) were available for evaluation. The rotational stability, as evaluated by pivot shift test, was significantly superior in the Group DB to that in the Group SB. No significant difference with regard to ACL revisions, total flexion work, mean peak flexion torque and extension work between the groups was detected. There was no significant difference between the groups in terms of the Tegner activity score, the knee injury and osteoarthritis outcome score, the Lysholm functional score, anterior knee pain or mobility, subjective knee function. In addition, no significant difference in laxity on the Lachman test or the KT-1000 maximum manual force test was investigated. All the results were significantly more satisfactory at each follow-up period than preoperatively, in both groups. Both SB- and DB-ACL reconstruction resulted in satisfactory subjective outcome and objective stability. Both these techniques can therefore be considered as suitable alternatives for ACL reconstruction. Moreover, as it seems to be according to the pivot shift test, the risk for the development of degenerative changes of the knee joint in a long run could be smaller in the Group DB.

Single-bundle versus double-bundle ACL reconstructions in isolation and in conjunction with extra-articular iliotibial band tenodesis

BACKGROUND

Intra-articular anterior cruciate ligament (ACL) reconstruction has been the primary treatment option for isolated ACL injuries for many years. An anatomic double-bundle reconstruction has been devised in an effort to improve rotational control. The role of the extra-articular iliotibial band tenodesis in ACL injuries has evolved from primary treatment, to an adjuvant secondary procedure, to being used more selectively in revision ACL reconstructions.

HYPOTHESES

1) Single-bundle and doublebundle intra-articular ACL reconstructions will both restore pre-injury laxity measurements in an isolated ACL injury cadaver model. 2) The deep iliotibial band structures contribute to rotational control and in a dual ACL + ITB injury cadaver model, ACL reconstruction alone cannot restore rotational control.

STUDY DESIGN

Controlled Laboratory Design.

METHODS

17 fresh frozen cadavers received intra-articular reconstructions, seven single-bundle and ten double-bundle; laxity was measured with the ACL intact/ITB intact, ACL reconstructed/ITB intact, after cutting the ITB, and after an ITB tenodesis procedure; laxity measurements of anterior tibial translation(ATT) and internal rotation(IR) were measured following applications of an anterior shear force, an internal torque and a coupled anterior shear force-internal torque at 30 and 90 degrees of flexion.

RESULTS

Single-bundle and double-bundle ACL reconstructions both restored IR to a native knee state under isolated internal torques and under coupled forces. Both reconstruction techniques also re-established anterior tibial translation to at least the pre-ACL injury level, with over-constraint in the double-bundle subgroup [5.00 (+2.11) to 3.50(+1.18), p-value 0.026] under coupled loads at 30 degrees of flexion. With the individual ACL reconstructions held constant, under coupled forces mean IR increased in the single-bundle subgroup [13.7(+1.1) to 17.6(+1.2), p-value 0.004] and the double-bundle subgroup [9.5(+1.0) to 12.4(+1.0), p-value 0.009] with the cutting of the ITB at 30 degrees. Under internal torque, mean IR increased in the single-bundle subgroup [14.0(+1.0) to 18.4(+1.6), p-value 0.016] with the cutting of the ITB at 30 degrees, while IR increased in the double-bundle subgroup [10.0(+1.3) to 13.4(+1.5), p-value 0.002] under the same internal torque at 90 degrees. With the ACL reconstruction held constant, ATT did not significantly change when the ITB was cut or when it was tenodesed under any specific loading condition.

CONCLUSION

Single-bundle and double-bundle intra-articular reconstructions were both able to restore internal rotation and anterior tibial translation to at least native knee laxity levels after an isolated laboratory ACL injury. When the ACL reconstructions were held constant, internal rotation statistically increased with the cutting of the ITB under multiple testing conditions in both the single-bundle and double-bundle subgroups.

Double-bundle versus single-bundle reconstruction for anterior cruciate ligament rupture in adults

BACKGROUND

Arthroscopic reconstruction for anterior cruciate ligament rupture is a common orthopaedic procedure. One area of controversy is whether the method of double-bundle reconstruction, which represents the 'more anatomical' approach, gives improved outcomes compared with the more traditional single-bundle reconstruction.

OBJECTIVES

To assess the effects of double-bundle versus single-bundle for anterior cruciate ligament reconstruction in adults with anterior cruciate ligament deficiency.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (to February 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 2), MEDLINE (1966 to February week 3 2012) and EMBASE (1980 to 2012 Week 8). We also searched trial registers, conference proceedings, and contacted authors where necessary.

SELECTION CRITERIA

Randomised and quasi-randomised controlled clinical trials comparing double-bundle versus single-bundle reconstruction for anterior cruciate ligament (ACL) rupture in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected articles, assessed risk of bias and extracted data. We contacted investigators to obtain missing information. Where appropriate, results of comparable studies were pooled.

MAIN RESULTS

Seventeen trials were included. These involved 1433 people, mostly young physically active adults. All included trials had methodological weaknesses and were at risk of bias, notably selection bias from inadequate or lack of allocation concealment. Data for pooling individual outcomes were available for a maximum of nine trials and 54% of participants.There were no statistically or clinically significant differences between double-bundle and single-bundle reconstruction in the subjective functional knee scores (subjective IKDC score, Tegner activity score, Lysholm score) in the intermediate (six months up to two years since surgery) or long term (two to five years from surgery). For example, the long term results for the Lysholm score (0 to 100: best score) were: mean difference (MD) 0.12, 95% confidence interval (CI) -1.50 to 1.75; 5 trials, 263 participants). The only trial reporting on long term knee pain found no statistically significant differences between the two groups. There were no significant differences between the two groups in adverse effects and complications (e.g. infection reported by nine trials (7/285 versus 7/393; risk ratio (RR) 1.14, 95% CI 0.46 to 2.81); graft failure reported by six trials (1/169 versus 4/185; RR 0.45; 95% CI 0.07 to 2.90).Limited data from five trials found a better return to pre-injury level of activity after double-bundle reconstruction (147/162 versus 208/255; RR 1.15, 95% CI 1.07 to 1.25). At long term follow-up, there were statistically significant differences in favour of double-bundle reconstruction for IKDC knee examination (normal or nearly normal categories: 325/344 versus 386/429; RR 1.05, 95% CI 1.01 to 1.08; 9 trials), knee stability measured with KT-1000 arthrometer (MD -0.74 mm, 95% CI -1.10 to -0.37; 5 trials, 363 participants) and rotational knee stability tested by the pivot-shift test (normal or nearly normal categories: 293/298 versus 382/415; RR 1.06, 95% CI 1.02 to 1.09; 9 trials). There were also statistically significant differences in favour of double-bundle reconstruction for newly occurring meniscal injury (9/240 versus 24/358; RR 0.46, 95% CI 0.23 to 0.92; 6 trials) and traumatic ACL rupture (1/120 versus 8/149; RR 0.17, 95% CI 0.03 to 0.96; 3 trials). There were no statistically significant differences found between the two groups in range of motion (flexion and extension) deficits.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine the relative effectiveness of double-bundle and single-bundle reconstruction for anterior cruciate ligament rupture in adults, although there is limited evidence that double-bundle ACL reconstruction has some superior results in objective measurements of knee stability and protection against repeat ACL rupture or a new meniscal injury. High quality, large and appropriately reported randomised controlled trials of double-bundle versus single-bundle reconstruction for anterior cruciate ligament rupture in adults appear justified.

Intraoperative correlation analysis between tunnel position and translational and rotational stability in single- and double-bundle anterior cruciate ligament reconstruction

PURPOSE

To determine the relation between the tunnel positions and the kinematic improvement of the knee joint after single-bundle (SB) and double-bundle (DB) anterior cruciate ligament (ACL) reconstructions.

METHODS

The study included 42 patients who underwent either SB (n = 21) or DB (n = 21) ACL reconstruction using hamstring tendon autograft. Anterior tibial translation and rotational laxity were measured by a navigation system before and after graft fixation. Three-dimensional computed tomography measurement was conducted for evaluation of tunnel placements. Regression analysis was carried out to determine the association between the postoperative kinematic change and the tunnel position.

RESULTS

The average tunnel location was mostly different between the SB and posterolateral bundle (PLB) tunnels, as well as between the anteromedial bundle (AMB) and PLB tunnels of DB ACL reconstructions, whereas the SB and AMB tunnels were similar in the tibial mediolateral and femoral deep-shallow positions. A regression curve showed that the PLB femoral tunnel position was correlated with rotation whereas both the SB and AMB femoral tunnel locations were mostly correlated with anterior tibial translation.

CONCLUSIONS

The PLB tunnel location in DB ACL reconstruction had a considerable effect on rotational laxity, whereas the SB and AMB tunnel locations mostly influenced anterior tibial translation.

LEVEL OF EVIDENCE

Level III, case-control study.

A systematic review of single-bundle versus double-bundle anterior cruciate ligament reconstruction

INTRODUCTION

Double-bundle (DB) anterior cruciate ligament (ACL) reconstruction is becoming increasingly common. However, no definitive data on the superiority of DB reconstruction have been shown when compared with single-bundle (SB) ACL reconstruction.

SOURCES OF DATA

We performed a comprehensive search of PubMed, Medline, Cochrane, CINAHL and Embase databases using various combinations of keywords such as 'ACL', 'reconstruction', 'DB' and 'SB'. Only articles published in peer-reviewed journals were included in this systematic review.

AREAS OF AGREEMENT

Several new techniques are available for ACL reconstruction. DB ACL reconstruction could provide better outcome for patients in terms of closer restoration of normal knee biomechanics and improving the rotatory laxity of the knee.

AREAS OF CONTROVERSY

Data are lacking to allow definitive conclusions on the use of DB reconstruction techniques for routine management of patients with ACL tear.

GROWING POINTS

Given the limitations of the current studies, it is not possible to recommend systematic use of DB ACL reconstruction. Even though biomechanical results are encouraging, subjective patient evaluation is similar for SB and DB reconstruction.

AREAS TIMELY FOR DEVELOPING RESEARCH

Studies of higher levels of evidence, for instances large adequately powered randomized trials, should be conducted to bring new insight in this field. With the current evidence available, a simple SB ACL reconstruction is a suitable technique, and it should be not abandoned until stronger scientific evidence in favour of DB ACL reconstruction will be produced.

Guideline on anterior cruciate ligament injury

The Dutch Orthopaedic Association has a long tradition of development of practical clinical guidelines. Here we present the recommendations from the multidisciplinary clinical guideline working group for anterior cruciate ligament injury. The following 8 clinical questions were formulated by a steering group of the Dutch Orthopaedic Association. What is the role of physical examination and additional diagnostic tools? Which patient-related outcome measures should be used? What are the relevant parameters that influence the indication for an ACL reconstruction? Which findings or complaints are predictive of a bad result of an ACL injury treatment? What is the optimal timing for surgery for an ACL injury? What is the outcome of different conservative treatment modalities? Which kind of graft gives the best result in an ACL reconstruction? What is the optimal postoperative treatment concerning rehabilitation, resumption of sports, and physiotherapy? These 8 questions were answered and recommendations were made, using the "Appraisal of Guidelines for Research and Evaluation" instrument. This instrument seeks to improve the quality and effectiveness of clinical practical guidelines by establishing a shared framework to develop, report, and assess. The steering group has also developed 7 internal indicators to aid in measuring and enhancing the quality of the treatment of patients with an ACL injury, for use in a hospital or practice.

Arthroscopic ACL reconstruction with reverse "Y"-plasty grafts and fixation in the femur with either a bioabsorbable interference screw or an Endobutton

We propose a new reverse "Y"-plasty graft for use in anterior cruciate ligament (ACL) reconstruction that involves double tibial tunnels and a single femoral tunnel. With this technique, the hamstrings were used as autografts and fixed separately with bioabsorbable interference screws (group A) or Endobuttons (group B) in femurs. A prospective series of 63 patients underwent primary reconstruction of the ACL; all procedures were performed by the same surgeon. Group A included 35 patients (22 male, 13 female), with a mean age of 25.5 (17-40) years, who were followed up for 28.5 (12-48) months. Group B included 28 patients (17 male, 11 female), with a mean age of 24.3 (18-38) years, who were followed up for 29.5 (12-46) months. Lysholm, International Knee Documentation Committee (IKDC) and Larson scoring were used to compare the therapeutic effects experienced at the knee. Lysholm scores were 93.26±2.67 (group A) and 93.81±2.42 (group B); Larson scores were 91.91±2.29 (group A) and 92.81±2.39 (group B); IKDC scores were 93.89±1.88 (group A) and 94.15±1.77 (group B). None of the scoring differences between groups were statistically significant (T(1)=0.849, P(1)=0.399, T(2)=1.506, P(2)=0.137, T(3)=0.560, P(3)=0.578). The Lachman test was negative in 46 patients (90.2%) and 51 knees, including 25 (89.3%) of the 28 knees in group A and 21 (91.3%) of the 23 knees in group B. Negative Pivot shift was present postoperatively in 49 knees of 51 patients (96.1%), including 27 (96.4%) of the 28 knees in group A and 22 (95.7%) of the 23 knees in group B. All of the patients in both groups achieved full extension and at least 135° of knee flexion. This novel technique involves the creation of double tibial tunnels and a single femoral tunnel. In the tibia, there was a bone bridge, ranging from 2 to 3mm, between the two bundles, which are tensioned at different degrees of flexion to maintain the stability of the knee. In the femur, the grafts were fixed with bioabsorbable interference screws or Endobuttons. The outcomes show that normal function and joint stability were achieved in both groups, as compared with preoperative measurements. Although the outcomes in group A (grafts fixed with the bioabsorbable interference screws in the femur) was better than those observed in group B (grafts fixed with Endobuttons), there was no statistical difference between the groups.

Anatomic anterior cruciate ligament reconstruction utilizing the double-bundle technique

The goal of every orthopaedic surgeon should be to restore anatomy as close as possible to normal. Intense research on reconstruction of the anterior cruciate ligament (ACL) and an advancing knowledge of the anatomy and function of the 2 primary bundles of the ACL have led to techniques of ACL reconstruction that more closely restore normal anatomy. Restoring the ACL footprint is one of the most important goals of the surgery, and the choice between anatomic single-bundle and double-bundle ACL reconstruction is determined by the anatomical features of each patient. After reconstruction, the graft undergoes a complex, lengthy process of remodeling; therefore, inappropriate (early), aggressive rehabilitation can lead to graft failure and compromise the patient's outcome. The purpose of this article is to provide an overview of the anatomy and function of the ACL, the methods for anatomic single-bundle and double-bundle ACL reconstruction, and our recommendations for postoperative rehabilitation.

Clinical outcomes of double- vs single-bundle anterior cruciate ligament reconstruction: a systematic review of randomized control trials

Clinical outcomes of anterior cruciate ligament (ACL) reconstruction with double-bundle and single-bundle techniques are still controversial. We therefore performed a systematic review to compare postoperative outcomes between the two techniques. Randomized control trials comparing the outcomes between the two techniques were identified from Medline and EMBASE since inception to April 27, 2011. Data were independently extracted by two reviewers. Thirteen of 318 studies were eligible; 9, 11, 7, and 8 studies were pooled for rotation, translation, function, and complication outcomes, respectively. The double-bundle technique was approximately four times (95% CI: 2.65, 11.99) and two times (95% CI: 1.16, 5.21) more likely to show a normal pivot shift and normal International Knee Documentation Committee (IKDC) grading compared with the single-bundle technique. However, there were nonsignificant differences in KT grading (OR = 1.66, 95% CI: 0.77, 3.82), IKDC score (0.29, 95% CI: -1.17, 1.75), Lysholm knee score (-0.87, 95% CI: -2.66, 0.93), Tegner activity score (0.37, 95% CI: -0.05, 0.79), and complications (OR = 1.11, 95% CI: 0.48, 2.57). Heterogeneity was present in some outcomes but there was no evidence of publication bias for any outcome. The double-bundle may be better than the single-bundle ACL reconstruction technique in rotational stability but not for function, translation, and complications.

A matched pairs comparison of single- versus double-bundle anterior cruciate ligament reconstructions, clinical results and manual laxity testing

PURPOSE

To compare the subjective clinical results as well as manual anterior and rotational stability in patients treated with either single- (SB) or double-bundle (DB) anterior cruciate ligament (ACL) reconstructions.

METHODS

Sixty-four patients who had undergone SB or DB hamstring ACL reconstruction with hamstrings were included in a retrospective matched pair analysis. At follow-up IKDC subjective, CKS, KOOS, CKS and a visual analogue satisfaction scale was assessed. A blinded surgeon examined the joint laxity and completed the objective IKDC. The KT-1000 was used to bilaterally test anterior tibial translation. Patients with confounding variables, which statistically influenced the clinical outcome (passive flexion and extension deficits, persistent quadriceps deficit, tibiofemoral osteoarthritis and non-repairable medial meniscus injury), were identified and excluded from the statistical analysis (n = 10).

RESULTS

For all subjective scores, DB patients reported increased scores compared with SB patients. While consistently higher scores were demonstrated, statistical significance was only achieved for the IKDC subjective (P = 0.04) and VAS satisfaction (P = 0.02). Graded stability results of the Lachman, anterior drawer and pivot-shift tests were significantly higher in the DB group and KT-1000 side-to-side difference was significantly better for DB (P = 0.01).

CONCLUSION

DB ACL reconstruction appeared to more consistently result in significantly higher subjective outcome scores and manual tests of joint stability than SB ACL reconstruction. Besides the surgical technique, normal extension and quadriceps strength after surgery were identified to be an essential component in order to provide the patient with a successful outcome.

Tibial rotation under combined in vivo loading after single- and double-bundle anterior cruciate ligament reconstruction

PURPOSE

To evaluate in vivo the differences in tibial rotation between single- and double-bundle anterior cruciate ligament (ACL)-reconstructed knees under combined loading conditions.

METHODS

An 8-camera optoelectronic system and a force plate were used to collect kinematic and kinetic data from 14 patients with double-bundle ACL reconstruction, 14 patients with single-bundle reconstruction, 12 ACL-deficient subjects, and 12 healthy control individuals while performing 2 tasks. The first included walking, 60° pivoting, and stair ascending, and the second included stair descending, 60° pivoting, and walking. The 2 variables evaluated were the maximum range of internal-external tibial rotation and the maximum knee rotational moment.

RESULTS

Tibial rotation angles were not significantly different across the 4 groups (P = .331 and P = .851, respectively) or when side-to-side differences were compared within groups (P = .216 and P = .371, respectively) for the ascending and descending maneuvers, nor were rotational moments among the 4 groups (P = .418 and P = .290, respectively). Similarly, for the descending maneuver, the rotational moments were not significantly different between sides (P = .192). However, for the ascending maneuver, rotational moments of the affected sides were significantly lower by 20.5% and 18.7% compared with their intact counterparts in the single-bundle (P = .015) and double-bundle (P = .05) groups, respectively.

CONCLUSIONS

High-intensity activities combining stair ascending or descending with pivoting produce similar tibial rotation in single- and double-bundle ACL-reconstructed patients. During such maneuvers, the reconstructed knee may be subjected to significantly lower rotational loads compared with the intact knee.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

An implant-free double-bundle reconstruction of the anterior cruciate ligament: operative technique and influence on tibiofemoral kinematics

BACKGROUND

Reconstruction of the anterior cruciate ligament is a standard surgical procedure in sports traumatology. The widespread replacement method using hamstring tendons has an important shortcoming namely delayed or missing bony healing in contrast to patellar tendon grafts where implant-free fixation is established by using the adjacent bone blocks. The purpose of this study was to describe a new implant-free surgical procedure using hamstring tendon grafts and to analyse the influence on tibiofemoral kinematics in vitro.

METHODS

Nine human knee specimens with arthroscopically transected anterior cruciate ligaments were mounted on a dynamic knee simulator and weight-bearing muscle-loaded knee flexions were simulated while a robotic universal force sensor system was used to provide external tibial loads. Three different loading conditions were simulated including partial body weight only, an additional 50 N anterior tibial force or an additional Five Nm of internal rotational torque. After reconstruction of the anterior cruciate ligament using a tibial bone block hybrid technique these three trials were repeated. The kinematics was measured with an ultrasonic measuring system and different loading and ligament conditions were examined. Graft tunnel placement was verified by computed tomography.

FINDINGS

Our fixation method achieved stability to anterior tibial drawer force whereas internal tibial rotation did not change before and after the reconstruction. Computed tomography confirmed anatomical graft and tunnel placement.

INTERPRETATION

The presented operative procedure is technically feasible and leads to reproducible results concerning knee joint kinematics and graft placement.

Double-bundle versus single-bundle anterior cruciate ligament reconstruction: randomized clinical and magnetic resonance imaging study with 2-year follow-up

BACKGROUND

One aspect of the debate over the reconstruction of the anterior cruciate ligament is whether it should be carried out with the single-bundle or double-bundle technique.

HYPOTHESIS

The double-bundle technique results in fewer graft failures than the single-bundle technique in anterior cruciate ligament reconstruction.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 153 patients were prospectively randomized into 2 groups of anterior cruciate ligament reconstruction with hamstring autografts using aperture interference screw fixation: single-bundle technique (SB group, n = 78) and double-bundle technique (DB group, n = 75). The evaluation methods were clinical examination, KT-1000 arthrometric measurement, the International Knee Documentation Committee (IKDC) and the Lysholm knee scores, and magnetic resonance imaging (MRI) evaluation. All of the operations were performed by 1 experienced orthopaedic surgeon, and all clinical assessments were made by 2 blinded and independent examiners. A musculoskeletal radiologist blinded to the clinical data made the MRI interpretation.

RESULTS

There were no differences between the study groups preoperatively. Ninety percent of patients (n = 138) were available at a minimum 2-year follow-up (range, 24-37 months). Eight patients (7 in the SB group and 1 in the DB group) had graft failure during the follow-up and had anterior cruciate ligament revision surgery (P = .04). In addition, 7 patients (5 in the SB group and 2 in the DB group) had an invisible graft on the MRI assessment at the 2-year follow-up. Also, the anteromedial bundle was partially invisible in 2 patients and the posterolateral bundle in 9 patients. Together, the total number of failures and invisible grafts were significantly higher in the SB group (12 patients, 15%) than the DB group (3 patients, 4%) (P = .024). No significant group differences were found in the knee scores or stability evaluations at the follow-up.

CONCLUSION

This 2-year randomized trial showed that the revision rate of the anterior cruciate ligament reconstruction was significantly lower with the double-bundle technique than that with the single-bundle technique. However, additional years of follow-up are needed to reveal the long-term results.

Anterior cruciate ligament reconstruction using remnant preservation and a femoral tensioning technique: clinical and magnetic resonance imaging results

PURPOSE

The purpose of this study was to investigate the clinical and magnetic resonance imaging (MRI) results of anterior cruciate ligament (ACL) reconstruction with autogenous hamstring tendon by use of remnant preservation and a femoral tensioning technique.

METHODS

A total of 53 patients who had ACL reconstruction by use of remnant ACL stump preservation and a femoral tensioning technique were evaluated. Clinical evaluation at a minimum of 2 years after surgery included range of motion, Lachman test, pivot-shift test, KT-2000 arthrometer testing (MEDmetric, San Diego, CA), and clinical scores. Plain radiographs were evaluated for tunnel enlargement. MRI was obtained for evaluation of graft continuity, cyclops-like mass lesion, and positioning of the tibial tunnel. Second-look arthroscopy was performed in 33 patients.

RESULTS

The clinical scores improved postoperatively. There were statistically significant differences between preoperative and postoperative Lachman tests, pivot-shift tests, and KT-2000 arthrometer measurements. Postoperative MRI was available in 48 patients, and it showed intact graft in 45 patients, 2 partial tears, and 1 complete loss of graft. There were cyclops-like mass lesions in 12 patients, but none showed an extension limitation or pain at extension. The position of the tibial tunnel on the sagittal and coronal view was similar to the position of the normal ACL tibial insertion. The measured tibial tunnel widening on the radiographs at final follow-up was 2.2 ± 1.5 mm.

CONCLUSIONS

Reconstruction of the ACL by use of preservation and femoral tensioning of the remnant tissue showed good clinical results without increased concerns regarding incorrect tunnel formation. Postoperative MRI showed an increased incidence of cyclops-like mass lesions, but no clinical significance was observed.

LEVEL OF EVIDENCE

Level IV, case series.

In vitro and intraoperative laxities after single-bundle and double-bundle anterior cruciate ligament reconstructions

PURPOSE

The purpose of this study was to objectively evaluate whether double-bundle anterior cruciate ligament (ACL) reconstruction can better restore the normal translational and rotational laxities than the conventional single-bundle ACL reconstruction among the reported biomechanical studies.

METHODS

A systematic literature search was conducted to identify in vitro and in vivo (intraoperative) biomechanical studies that compared the laxities (anterior or anteroposterior or rotational) between single- and double-bundle ACL reconstructions. Because of large variability among the loading conditions and testing methods used to determine the rotational laxities among the studies, a meta-analysis of rotational laxities was not feasible.

RESULTS

Seven in vitro and three in vivo studies were included in this analysis based on the predefined inclusion criteria. The overall mean differences calculated by the random effects model in anteroposterior laxity between the single-bundle and double-bundle ACL reconstruction techniques at 0°, 30°, 60°, and 90° of flexion were 0.99 mm, 0.38 mm, 0.34 mm, and 0.07 mm, respectively. No statistically significant difference was noted between the 2 treatments at all flexion angles. Among the 9 studies that compared the rotational laxity of single-bundle and double-bundle ACL reconstructions, 4 reported that double-bundle reconstruction can provide better rotational control than single-bundle reconstruction. The other 5 studies could not identify any significant difference between the 2 reconstructions in terms of rotational laxity.

CONCLUSIONS

Both single- and double-bundle treatment options for ACL injury result in similar anteroposterior knee joint laxity at time 0. No conclusive evidence on the superiority of 1 reconstruction technique over the other in terms of rotation laxity can be obtained because of several variations in the experimental protocol and the kinematics used to measure the rotational laxity among the studies.

LEVEL OF EVIDENCE

Level III, meta-analysis.

Single-bundle patellar tendon versus non-anatomical double-bundle hamstrings ACL reconstruction: a prospective randomized study at 8-year minimum follow-up

PURPOSE

The purpose of this study was to compare subjective, objective and radiographic outcome of the lateralized single-bundle bone-patellar tendon-bone autograft with a non-anatomical double-bundle hamstring tendons autograft anterior cruciate ligament (ACL) reconstruction technique at long-term follow-up.

METHODS

Seventy-nine non-consecutive randomized patients (42 men; 37 women) with unilateral ACL insufficiency were prospectively evaluated, before and after ACL reconstruction by means of the above-mentioned techniques, with a minimum follow-up of 8 years (range 8-10 years; mean 8.6 years). In the double-bundle hamstrings technique, we used one tibial and one femoral tunnel combined with one "over-the-top" passage, cortical staple's fixation and we left intact hamstrings' tibial insertion. Patients were evaluated subjectively and objectively, using IKDC score, Tegner level, manual maximum displacement test with KT-2000™ arthrometer. Radiographic evaluation was performed according to IKDC grading system, and re-intervention rate for meniscal lesions was also recorded.

RESULTS

The subjective and objective IKDC were similar in both groups while double-bundle hamstrings group showed significantly higher Tegner level (P = 0.0007), higher passive range of motion recovery (P = 0.0014), faster sport resumption (P = 0.0052), lower glide pivot-shift phenomenon (P = 0.0302) and lower re-intervention rate (P = 0.0116) compared with patellar tendon group. Radiographic evaluation showed significant lower objective degenerative changes in double-bundle hamstrings group at final follow-up (P = 0.0056).

CONCLUSION

Although both techniques provide satisfactory results, double-bundle ACL reconstruction shows better functional results, with a faster return to sport activity, a lower re-operation rate and lower degenerative knee changes.

In vivo stability and clinical comparison of anterior cruciate ligament reconstruction using low or high femoral tunnel positions

BACKGROUND

Several biomechanical studies have supported placing the femoral tunnel at a low position (10 or 2 o'clock) to achieve anterior and rotational knee stabilities after anterior cruciate ligament (ACL) reconstruction. However, no firm consensus has been reached regarding the merits and demerits of ACL reconstruction using a low femoral tunnel versus a high femoral tunnel (11 or 1 o'clock).

HYPOTHESIS

A low femoral tunnel position during ACL reconstruction provides better intraoperative stability (especially, rotational stability) and clinical outcomes than does a high femoral tunnel position.

STUDY DESIGN

Cohort study; Level of evidence 2.

METHODS

Sixty-two patients who underwent ACL reconstruction were equally allocated to low and high femoral tunnel groups; 58 were followed up for a minimum of 2 years (29 in the each group). After reconstruction and using a navigation system, the authors compared intraoperative anterior, internal rotational, and external rotational stabilities at 0°, 30°, 60°, and 90° of knee flexion and compared clinical outcomes, including Lysholm knee scores, Tegner activity scores, Lachman and pivot-shift test findings, and radiographic stabilities at final follow-up visits.

RESULTS

The low group showed significantly better intraoperative internal rotational stability at 0° and 30° of flexion but not at other angles (60° and 90°). Intraoperatively, no significant intergroup differences were found for anterior and external rotational stabilities at any flexion angle. Furthermore, clinical outcomes, including Lysholm knee and Tegner activity scores, showed no significant differences between the 2 groups at final follow-up visits (P > .05), and Lachman and pivot-shift test stability results and radiological stability data obtained at final follow-up were not significantly different between the 2 groups (P > .05).

CONCLUSION

The low femoral tunnel group showed better internal rotational stability at time zero during ACL reconstruction but similar anterior and external rotational stabilities. No significant differences were observed between the 2 groups in terms of clinical outcomes and stabilities after a minimum follow-up of 2 years.

Cost-effectiveness of anterior cruciate ligament reconstruction: a preliminary comparison of single-bundle and double-bundle techniques

BACKGROUND

There has been growing interest in anatomical reconstruction of the anterior cruciate ligament (ACL), including the use of double-bundle (DB) reconstruction techniques.

HYPOTHESIS

The DB technique will not be cost-effective when compared with single-bundle (SB) reconstruction.

STUDY DESIGN

Economic and decision analysis; Level of evidence, 1.

METHODS

A decision-analysis model with input values derived from the literature was used to estimate the cost-effectiveness of DB ACL reconstruction compared with SB ACL reconstruction. Effectiveness was based on the revision rate and the postoperative International Knee Documentation Committee (IKDC) score.

RESULTS

Sixty-four percent of DB knees result in an IKDC score of A, compared with 54% of SB knees. The incremental cost-effectiveness ratio of a DB reconstruction compared with an SB reconstruction was $6416 per quality adjusted life year in the baseline scenario and $64 371 per quality adjusted life year in the alternate scenario. The model is very sensitive to the proportions of IKDC A outcomes. The model is also sensitive to the utility values assigned to IKDC A and B outcomes and is less sensitive to the marginal cost of a DB reconstruction.

CONCLUSION

This preliminary analysis based on published clinical results to date shows DB ACL reconstruction may be cost-effective, despite increased upfront cost. More research is needed to confirm whether there is any difference in the distribution of IKDC outcomes between the 2 techniques. Perhaps more importantly, the lack of any other demonstrated clinical benefit from the DB technique questions the clinical relevance of this difference in IKDC scores.

CLINICAL RELEVANCE

Revision data and longer term outcomes after DB reconstruction and more reliable clinical utility data are needed to definitively compare the cost-effectiveness of DB and SB ACL reconstruction. Studies of ACL reconstruction and other sports medicine procedures should report the distribution of outcomes data to facilitate future analyses of clinical effectiveness.

ACL reconstruction in sports active people: transtibial DB technique with ST/G vs. transtibial SB technique with BPTB: preliminary results

The single-bundle ACL reconstruction ensures good outcomes and it is a well-established and widespread technique. Nevertheless, some patients still present residual pain and instability. Recent studies have showed that the double-bundle technique restores better natural ACL-fitting kinematics. Long-term clinical studies comparing the two surgical techniques are not frequent and there is no instrument to evaluate function and kinematics during the knee rotation in vivo. In this randomised prospective study performed on sportive people, we compare the BPTB single-bundle ACL reconstruction technique, which is the most common surgical technique performed on these patients' category, with the ACL double-bundle reconstruction technique (DB), in order to evaluate possible differences between the groups. Comparing the two groups, no statistically significant difference regarding the post-operative Lysholm score (p=0.368) the Tegner activity scale (p=0.519) and the arthrometric evaluation with KT-1000 (p=0.74) have been observed. On the contrary, the IKDC evaluation showed a statistically significant difference (p=0.004) better results of the DB group. Moreover, as assessed by the Tegner activity scale, only patients of the DB group were able to return to sports at a pre-injury level. Our data suggest that the double bundle ST/G ACL reconstruction technique results into slightly better outcome than the traditional technique of single-bundle BPTB. The verification and quantification of the advantages of this technique is anticipated with future studies focusing to the accurate measurement of knee rotation during different activities.

Comparison of intraoperative stability in ACL reconstruction based on femoral tunnel positions

This study evaluated and compared the intraoperative stabilities using the low and high femoral tunnel techniques in ACL reconstruction. Seventy patients who underwent ACL reconstruction were equally allocated to low or high femoral tunnel groups (35 in the low femoral tunnel group and 35 in the high femoral tunnel group) for this study. The authors compared intraoperative anterior, internal rotational, and external rotational stabilities at 0°, 30°, 60°, and 90° of knee flexion using a navigation system after reconstruction. The low femoral tunnel group showed significantly better intraoperative internal rotational stability at 0° and 30° of flexion than the high tunnel group; however, no significant intergroup differences were found for anterior and external rotational stabilities at any flexion angle. These findings suggested that the low femoral tunnel group showed better internal rotational stability at time zero condition during ACL reconstruction than the high femoral tunnel group, but anterior and external rotational stabilities were similar. However, to determine whether these results may affect clinical results, further studies based on more accurate measurement of rotational stability in clinical settings are needed.

Anatomic double-bundle anterior cruciate ligament reconstruction

Several double-bundle anterior cruciate ligament (ACL) reconstruction procedures were reported in the 1980s and 1990s. However, no significant differences were found in the clinical results between these double-bundle procedures and single-bundle procedures because the double-bundle procedures appeared to reconstruct only the anteromedial bundle with 2 bundles. In the early 2000s, we proposed a new concept of anatomic reconstruction of the anteromedial and posterolateral bundles, in which 4 independent tunnels were created through the center of each anatomic attachment of the 2 bundles. We called it "anatomic" double-bundle ACL reconstruction. Biomechanical studies have shown that the anatomic double-bundle ACL reconstruction can restore knee stability significantly more closely to the normal level than the conventional single-bundle reconstruction. Recent intraoperative measurement studies have shown that the clinically available anatomic double-bundle procedures can reconstruct knee stability significantly better and improve knee function close to the normal level at the time immediately after surgery compared with the conventional single-bundle procedures. However, the greatest criticism of the anatomic double-bundle reconstruction is whether its clinical results are better than the results of single-bundle reconstruction. To date (January 2010), 10 prospective comparative clinical trials (Level I or II) and 1 meta-analysis have been reported comparing single-bundle and anatomic double-bundle reconstructions using hamstring tendons. In 8 of the 10 studies, the anterior and/or rotatory stability of the knee was significantly better with the anatomic double-bundle ACL reconstruction than with the conventional single-bundle reconstruction. However, 1 original trial and the meta-analysis found that there were no differences in the results between the 2 types of reconstructions. Thus the utility of the anatomic double-bundle reconstruction has not yet been established. Our review does show how much evidence exists as to the benefits of double-bundle ACL reconstruction at present.

Kinematic impact of anteromedial and posterolateral bundle graft fixation angles on double-bundle anterior cruciate ligament reconstructions

BACKGROUND

Currently in double-bundle anterior cruciate ligament (ACL) reconstructions, the range of knee flexion angles that surgeons use for anteromedial (AM) and posterolateral (PL) bundle graft fixation spans from 0 degrees to 90 degrees for both bundle grafts. Despite the recent popularity of this procedure, no consensus exists on an optimal set of AM and PL graft fixation angles.

HYPOTHESIS

Graft fixation angles that simulate the native tensioning relationship of the AM and PL bundles will produce kinematic results similar to the intact knee, while graft fixation angles that do not simulate this relationship will under- or overconstrain the knee.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twelve cadaveric knees were biomechanically tested in the intact state, ACL-sectioned state, and a randomized order of 7 double-bundle ACL reconstructed states at multiple graft fixation angle combinations. For each test state, data were collected for 88 N anterior tibial loads, 10 N.m valgus torques, 5 N.m internal rotation torques, and 2 simulated pivot shift loads consisting of a 5 N.m internal rotation torque coupled with either a 10 N.m valgus torque or an 88 N anterior tibial load at 0 degrees, 20 degrees, 30 degrees, 60 degrees, and 90 degrees of knee flexion.

RESULTS

The AM and PL graft fixation angle combinations of 0 degrees /0 degrees (AM graft fixation angle/PL graft fixation angle), 60 degrees /0 degrees, 45 degrees /15 degrees, and 75 degrees /15 degrees restored normal laxity to the reconstructed knee in all of the biomechanical tests. The 30 degrees /30 degrees, 60 degrees /60 degrees, and 90 degrees /90 degrees graft fixation angle combinations significantly restricted knee laxity compared with the intact state in various biomechanical tests.

CONCLUSION

We found that as long as the PL bundle graft was fixed between 0 degrees and 15 degrees , the AM graft could be fixed up to 75 degrees without restricting knee laxity. However, fixation of the PL graft at 30 degrees of knee flexion and above significantly overconstrained the knee.

CLINICAL RELEVANCE

This study provides a range of angles that can be used in double-bundle ACL reconstructions to restore normal knee stability without causing overconstraint.

Tunnel position and relationship to postoperative knee laxity after double-bundle anterior cruciate ligament reconstruction with a transtibial technique

BACKGROUND

Several laboratory studies have pointed out a potential risk of femoral tunnel misplacement in anterior cruciate ligament reconstruction with a transtibial technique. The tunnel malposition away from the anatomic attachment may result in increased postoperative knee laxity in double-bundle reconstruction.

PURPOSE

This study was conducted to evaluate the femoral and tibial tunnel positions in transtibial double-bundle reconstruction, and to determine the relationship between the tunnel positions and the results of the postoperative knee laxity examinations.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Fifty-three of 71 patients who underwent transtibial double-bundle reconstruction from 2004 to 2005 were followed more than 24 months. The tunnel positions for the anteromedial and posterolateral grafts were measured using 3-dimensional computed tomography images applying the quadrant method. The postoperative knee laxity was examined with the KT-1000 arthrometer manual maximum test, anterior drawer test, and pivot-shift test.

RESULTS

The deep-shallow position (parallel to Blumensaat's line) and high-low position (perpendicular to Blumensaat's line) of the femoral tunnels were 27.7% +/- 5.6% from the most posterior condylar contour and 16.3% +/- 5.2% from Blumensaat's line for the anteromedial graft, and 35.5% +/- 6.4% and 48.0% +/- 5.4% for the posterolateral graft. The medial-lateral and anterior-posterior positions of the tibial tunnels were 46.1% +/- 2.6% from the most medial contour and 36.5% +/- 4.9% from the most anterior contour for the anteromedial graft, and 47.5% +/- 3.1% and 51.6% +/- 5.0% for the posterolateral graft. There was no statistical correlation between any parameters of the femoral or tibial tunnel position and the results of the knee laxity tests.

CONCLUSION

The femoral tunnels placed in transtibial double-bundle reconstruction were located appropriately in high-low and deep-shallow orientation, but had larger variability than the previously reported data of the anatomic femoral attachment. However, the variability of the femoral tunnel position was not so large as to result in graft insufficiency with increased postoperative knee laxity.

Comparison between single-and double-bundle anterior cruciate ligament reconstruction: a prospective, randomized, single-blinded clinical trial

BACKGROUND

Double-bundle ACL reconstruction popularity is increasing with the aim to reproduce native ACL anatomy and improve ACL reconstruction outcome. However, to date, only a few randomized clinical studies have been published.

PURPOSE

The aim of this study was to prospectively compare the clinical results of single- and double-bundle ACL reconstruction.

STUDY DESIGN

Randomized controlled clinical trial; Level of evidence, 1.

METHODS

Seventy patients with a chronic unilateral ACL rupture who underwent arthroscopically assisted ACL reconstruction using a hamstring graft were randomized to receive a single- (SB) or double-bundle (DB) reconstruction. Both groups were comparable with regard to preoperative data. A double-incision surgical technique was adopted in both groups. The graft was fixed by looping the hamstring tendons around a bony (DB) or a metallic (SB) bridge on the tibial side and with interference screws reinforced with a staple on the femur. The same rehabilitation protocol was adopted. Outcome assessment was performed by a blinded, independent observer using the visual analog scale (VAS) score, the new International Knee Documentation Committee (IKDC) form, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and KT-1000 arthrometer evaluation.

RESULTS

All the patients reached a minimum follow-up of 2 years. No differences between the 2 groups were observed in terms of KOOS and IKDC subjective score. A statistically significant difference in favor of the DB group was found with the VAS (P < .03). The objective IKDC final scores showed statistically significantly more "normal knees" in the DB group than in the SB group (P = .03). There was 1 stability failure in the DB group and 3 in the SB group. The KT-1000 arthrometer data showed a statistically significant decrease in the average anterior tibial translation in the DB group (1.2 mm DB vs 2.1 mm SB; P < .03). The incidence of a residual pivot-shift glide was 14% in DB and 26% in SB (P = .08).

CONCLUSION

In the 2-year minimum follow-up, DB ACL reconstructions showed better VAS, anterior knee laxity, and final objective IKDC scores than SB. However, longer follow-up and accurate instrumented in vivo rotational stability assessment are needed.