Intercondylar roof impingement after anatomic double-bundle anterior cruciate ligament reconstruction in patients with knee hyperextension

Editorial Commentary: Failure to Regain Full Hyperextension After Anterior Cruciate Ligament Reconstruction Is Associated With Inferior Patient Satisfaction and Lower Functional Outcomes Scores, But the Impact on Graft Rupture Rates and Persistent Instability Is Unclear

Up to one half of patients undergoing anterior cruciate ligament reconstruction demonstrate some degree of knee hyperextension in their contralateral limb. In most cases, this is mild (1°-5°), but it is reported that 9% and 0.8% demonstrate moderate (6°-10°) and severe (>10°) degrees of hyperextension. These characteristics pose challenges and considerations for surgical management. This includes the finding that failure to regain full hyperextension is common and is associated with inferior functional outcomes and patient satisfaction, and the juxtaposition that regaining full hyperextension may increase graft rupture and persistent instability rates. Although the pathophysiology of extension deficit is multifactorial, 2 particularly important and modifiable risk factors in this population are notch impingement and arthrogenic muscle inhibition. Strategies to avoid notch impingement include anterior notchplasty and careful consideration of graft size, graft type, and tibial tunnel placement. Arthrogenic muscle inhibition is clinically characterized by extension deficit and quadriceps activation failure. It is reversible in most patients and therefore an important modifiable risk factor. Since failure to regain full hyperextension is associated with inferior outcomes, abolishing extension deficit should be a key objective of surgical treatment and rehabilitation. Concerns regarding the risks of persistent laxity and graft rupture in knee hyperlaxity/hyperextension patients can be mitigated by the addition of anterolateral ligament reconstruction.

Increased Posterior Tibial Slope Is Associated With Greater Risk of Graft Roof Impingement After Anatomic Anterior Cruciate Ligament Reconstruction

BACKGROUND

Increased posterior tibial slope (PTS) has been reported to be associated with irreducible anterior tibial subluxation in extension after anatomic anterior cruciate ligament (ACL) reconstruction (ACLR), which raises concerns about the greater risk of graft roof impingement (GRI) although the tibial tunnel is positioned anatomically.

HYPOTHESIS

Increased PTS would be associated with greater risk of GRI after anatomic ACLR.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Between January 2016 and December 2017, a total of 418 consecutive patients were diagnosed as having noncontact ACL injuries and underwent primary anatomic ACLR. Among them, 26 patients had ≥1 of the following features during the second-look arthroscopy: fractured/guillotined bundles at the tibial insertion or cyclops lesion. These patients were confirmed to have GRI and were allocated to the study group. They were also matched 1:2 to 52 control participants without GRI. PTS was measured on true lateral whole-leg radiographs. Intra-articular ACL graft signal intensity was evaluated on postoperative magnetic resonance imaging scans (mean, 32.8 months; range, 26-38 months) and divided into 3 grades (I, good; II, moderate; III, poor) based on degree of GRI. Moreover, anterior subluxation of the lateral compartment (ASLC) and medial compartment (ASMC) in extension relative to the femoral condyles were measured on postoperative magnetic resonance imaging scans and compared between the groups. In addition, predictors of GRI were evaluated using multivariate logistic regression analysis and included body mass index, PTS, pivot-shift test, KT-1000 side-to-side difference, and concomitant meniscal tears.

RESULTS

PTS in the study group was significantly higher than that in control group (mean ± SD, 13.8°± 1.5° vs 9.5°± 1.8°; P < .05). In the study group (n = 26), patients with grade III (poor) graft signal intensity (n = 9) showed significantly higher PTS than those with grade II (moderate; n = 17) (16.4°± 1.7° vs 12.4°± 1.3°; P < .05). Moreover, the mean postoperative ASLC and ASMC in extension were significantly larger in the study group than the control group (ASLC, 4.1 ± 1.3 vs 0.8 ± 0.4 mm; ASMC, 4.3 ± 1.5 vs 0.9 ± 0.3 mm; P < .05). Furthermore, the abnormal degree of PTS (≥12°) was determined to be an independent risk factor associated with GRI after anatomic ACLR (odds ratio, 9.0 [95% CI, 3.7-30.2]; P < .001), whereas body mass index, grade of pivot-shift test, KT-1000 side-to-side difference, and concomitant meniscal tears were not.

CONCLUSION

Increased PTS (≥12°) was associated with greater risk of GRI after anatomic ACLR. This may provide additional information for counseling patients with greater risk of GRI.

Radiographic assessment of the tibiofemoral relationship in anterior cruciate ligament deficient knees

Background

The intercondylar roof line is one of the indicators used during anterior cruciate ligament (ACL) reconstruction to see the relation to the position of the tibial tunnel. The tibial tunnel can be made posteriorly in the anteriorly subluxated tibia. During ACL reconstruction, the tibiofemoral relationship of the opposite or normal knee should be considered. The purpose of this study was to examine the radiographic tibiofemoral relationship of the sagittal plane in a standing position in ACL deficient knees.

Methods

In this study, 64 patients were evaluated for inclusion. Lateral radiographs of the injured and uninjured knee were obtained preoperatively in a standing position. The knee was fully extended with the opposite foot on a step, asking the patients to bear weight fully on one leg. The tibiofemoral relationship was evaluated in the radiographs.

Results

The mean value of anterior tibial subluxation was 1.2 mm in the injured side and -1.6 mm in the uninjured side. The tibia was located in a significantly anterior position in the injured knee (p < 0.0001). The mean distance of the space for the ACL was 9.7 mm in the injured side and 10.7 mm in the uninjured side (p < 0.01). Roof-plateau angle averaged 63.6° in the injured side and 67.4° in the uninjured side (p < 0.001).

Conclusion

The tibiofemoral relationship of the ACL deficient knee was different from that of normal knee in the standing position. The relationship of the normal knee should be considered during ACL reconstruction and the risk of secondary lesions in the ACL deficient knee in activities of daily life should be considered.

Risk factors for postoperative graft laxity without re-injury after double-bundle anterior cruciate ligament reconstruction in recreational athletes

BACKGROUND

Although high activity is a risk factor for graft failure after anterior cruciate ligament (ACL) reconstruction, the risk factors for postoperative laxity after ACL reconstruction in recreational athletes are unknown.

METHODS

We enrolled 91 patients (40 males, 51 females; mean age 29.2 years; mean follow-up 4.3 years) who scored ≤ 6 on the Tegner activity scale, underwent double-bundle ACL reconstruction between 2010 and 2018, and did not experience re-injury. In the stable group (75 patients, <3.0 mm side-to-side difference (SSD) in anterior translation, grade 0 or 1 pivot shift 1 year after surgery) and unstable group (16 patients, ≥3.0 mm SSD, ≥grade 2 pivot shift), multivariate logistic regression analyses adjusted for factors showing P ≤ 0.3 on univariate analysis assessed risk factors for graft laxity. Lysholm score and graft intensity on MRI (Howell grade) were compared at final follow-up.

RESULTS

Mean SSD in anterior translation was 0.7 mm (stable group) and 3.3 mm (unstable group). Pivot shift grades were 0 (88%) and 1 (12%) in the stable group, and 0 (12.5%), 1 (50%), and 2 (37.5%) in the unstable group. Multivariate regression analyses showed that younger age and knee hyperextension were significant risk factors for graft laxity (P = 0.018 and 0.0016; cutoffs 18 years old and 8°, respectively). Lysholm scores in both groups were comparable, but graft intensity on MRI demonstrated significantly worse Howell grade in the unstable group (P = 0.002).

CONCLUSION

Younger age and knee hyperextension were risk factors for postoperative graft laxity without re-injury in recreational athletes.

Intercondylar Notch Impingement of the Anterior Cruciate Ligament: A Cadaveric In Vitro Study Using Robots

Background

Research has indicated that a smaller intercondylar notch could cause contact between the anterior cruciate ligament and the femoral notch, which may predispose individuals to an increased rate of anterior cruciate ligament injury.

Hypothesis

Contact between the lateral notch wall and the anterior cruciate ligament does increase the strain past the structural integrity of the ligament.

Study Design

A descriptive laboratory study.

Methods

A biomechanical study using robotic manipulators was conducted to investigate the occurrence of impingement in human cadaver specimens. Six cadaveric knees from six donors (three male and three female) were instrumented with a thin force sensor, placed on the lateral wall of the femoral condyle, and a differential variable reluctance transducer (DVRT) was attached to the middle section of the anterior medial bundle of the ACL. The knees were then moved through a series of flexion (5° to 90°), valgus (0 to 7.5°), and external rotation (0 to 7.5°) movements using two interacting robots.

Results

The results revealed that impingement occurred in both male and female specimens with a maximum impingement force of 28 N. Impingement occurred more prominently in female knees and in the combination loading of valgus and external rotation for both genders. The corresponding strain due to impingement was small or compressive, with the male knee maximum strain less than 1.28% and the female knee strain less than 7.1% in the worse case conditions.

Conclusion

The lack of increased force or strain when impingement occurred indicates that impingement may not affect the healthy function of the knee with a nonstenotic notch. Additionally, the analysis shows that impingement may not be a major contributing factor to anterior cruciate ligament injury, but rather a common occurrence in healthy knees.

Clinical Relevance

Impingement within the femoral notch does not appear to be a major contributory factor to ACL injury. Other more severe injuries to the knee would occur before ACL impingement with the femoral notch becoming a contributing factor to ACL injury. The small sample size limits the conclusivity of the results presented in this research; thus, additional large sample size studies are warranted.

Physiologic Preoperative Knee Hyperextension Is a Predictor of Failure in an Anterior Cruciate Ligament Revision Cohort: A Report From the MARS Group

BACKGROUND

The occurrence of physiologic knee hyperextension (HE) in the revision anterior cruciate ligament reconstruction (ACLR) population and its effect on outcomes have yet to be reported. Hypothesis/Purpose: The prevalence of knee HE in revision ACLR and its effect on 2-year outcome were studied with the hypothesis that preoperative physiologic knee HE ≥5° is a risk factor for anterior cruciate ligament (ACL) graft rupture.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Patients undergoing revision ACLR were identified and prospectively enrolled between 2006 and 2011. Study inclusion criteria were patients undergoing single-bundle graft reconstructions. Patients were followed up at 2 years and asked to complete an identical set of outcome instruments (International Knee Documentation Committee, Knee injury and Osteoarthritis Outcome Score, WOMAC, and Marx Activity Rating Scale) as well as provide information regarding revision ACL graft failure. A regression model with graft failure as the dependent variable included age, sex, graft type at the time of the revision ACL surgery, and physiologic preoperative passive HE ≥5° (yes/no) to assess these as potential risk factors for clinical outcomes 2 years after revision ACLR.

RESULTS

Analyses included 1145 patients, for whom 2-year follow-up was attained for 91%. The median age was 26 years, with age being a continuous variable. Those below the median were grouped as "younger" and those above as "older" (age: interquartile range = 20, 35 years), and 42% of patients were female. There were 50% autografts, 48% allografts, and 2% that had a combination of autograft plus allograft. Passive knee HE ≥5° was present in 374 (33%) patients in the revision cohort, with 52% being female. Graft rupture at 2-year follow-up occurred in 34 cases in the entire cohort, of which 12 were in the HE ≥5° group (3.2% failure rate) and 22 in the non-HE group (2.9% failure rate). The median age of patients who failed was 19 years, as opposed to 26 years for those with intact grafts. Three variables in the regression model were significant predictors of graft failure: younger age (odds ratio [OR] = 3.6; 95% CI, 1.6-7.9; P = .002), use of allograft (OR = 3.3; 95% CI, 1.5-7.4; P = .003), and HE ≥5° (OR = 2.12; 95% CI, 1.1-4.7; P = .03).

CONCLUSION

This study revealed that preoperative physiologic passive knee HE ≥5° is present in one-third of patients who undergo revision ACLR. HE ≥5° was an independent significant predictor of graft failure after revision ACLR with a >2-fold OR of subsequent graft rupture in revision ACL surgery. Registration: NCT00625885 ( ClinicalTrials.gov identifier).

Y-reconstruction could be better for ACL reconstruction in knee hyperextension versus double-bundle double-tunnel technique: a retrospective comparative study of 56 patients

PURPOSE

To compare the clinical outcomes of double-bundle (DB) single-tibial tunnel technique and double-tunnel technique for ACL reconstruction in patients with knee hyperextension.

METHODS

Defined as having constitutional hyperextension of greater than 10°, 56 patients with knee hyperextension who underwent ACL reconstruction were included in this study. To exclude concomitant lesions, preoperative magnetic resonance imaging (MRI) was performed in all knees. 24 patients (Group A) were treated with the anatomic DB/single-tibial tunnel ACL reconstruction and 32 patients (Group B) were treated with DB/double-tibial tunnel ACL reconstruction, all the included patients had knee hyperextension. Clinical results were evaluated by the extension angle, ROM, IKDC 2000 subjective score, rotational stability, pivot-shift test and anterior-posterior translation test before the operation and at the end of follow-up. MRI scan of the knee positioned in full extension was performed after 6 months post-operation. Location of tibial tunnels and graft signal intensity were assessed according to the MRI.

RESULTS

Postoperative extension deficit was detected in Group B, ROM of the injured knee in Group A was from extension angle 8.91 ± 3.16° to flexion angle 115.58 ± 10.53°. ROM of the injured knee in Group B was from extension angle - 2.13 ± 5.88° to flexion angle 119.25 ± 12.63°. Flexion angles of two groups did not show any significant difference (p = 0.24), while extension angles were quite different (p < 0.0001). Group A was slightly higher than Group B in IKDC subjective scores, but without significant difference (Group A 45.1 ± 6.5, Group B 42.4 ± 4.8, p = 0.09). There was no significant difference between two groups in pivot-shift test. Post-operational MRI showed more anterior located tibial tunnel and higher graft signal intensity in Group B when compared with Group A. One patient in the Group B had ligament retear, and required revision surgery.

CONCLUSION

DB/single-tibial tunnel technique restored the knee stability and overcame the shortcomings (such as knee extension deficit and graft impingement) of DB/double tibial tunnel, which might be more suitable for ACL reconstruction in knees with hyperextension.

LEVEL OF EVIDENCE

Level II to III.

Knee hyperextension does not adversely affect dynamic in vivo kinematics after anterior cruciate ligament reconstruction

PURPOSE

To evaluate the effect of knee hyperextension on dynamic in vivo kinematics after anterior cruciate ligament reconstruction (ACL-R).

METHODS

Forty-two patients underwent unilateral ACL-R. Twenty-four months after surgery, subjects performed level walking and downhill running on a treadmill while dynamic stereo radiographs were acquired at 100 (walking) and 150 Hz (running). Tibiofemoral motion was determined using a validated model-based tracking process, and tibiofemoral translations/rotations were calculated. The range of tibiofemoral motions from 0 to 10% of the gait cycle (heel strike to early stance phase) and side-to-side difference (SSD) were calculated. Maximum knee extension angle of ACL-reconstructed knees during walking was defined as active knee extension angle in each subject. Correlations between maximum knee extension angle and tibiofemoral kinematics data were evaluated using Spearman's rho (P < 0.05).

RESULTS

No significant correlation was observed between maximum knee extension angle and the range of anterior tibial translation during functional activities in the ACL-R knees. Maximum knee extension angle was weakly correlated with internal tibial rotation range in ACL-R knee during running (ρ = 0.376, P = 0.014); however, maximum extension angle was not correlated with SSD of internal tibial rotation. SSD of internal tibial rotation was -0.4° ± 1.9° (walking), -1.6° ± 3.1° (running), indicating ACL-R restored rotatory knee range of motion during functional movements.

CONCLUSION

Knee hyperextension was not significantly correlated with greater SSD of anterior translation and internal rotation. The clinical relevance is that knee hyperextension does not adversely affect kinematic outcomes after ACL-R and that physiologic knee hyperextension can be restored after ACL-R when knee hyperextension is present.

LEVEL OF EVIDENCE

III.

Contralateral knee hyperextension is associated with increased anterior tibial translation and fewer meniscal injuries in the anterior cruciate ligament-injured knee

PURPOSE

To investigate the influence of hyperextension of the contralateral healthy knee on anterior tibial translation (ATT) and the presence of associated injuries in the anterior cruciate ligament (ACL)-injured knee.

METHODS

A local patient data register containing the surgical and clinical data of patients undergoing ACL reconstruction was analyzed. Patients were divided into groups according to the degree of hyperextension of the contralateral knee: normal (Group A ≤ 0°), mild (Group B 1°-5°), moderate (Group C 6°-10°), and severe (Group D > 10°). The ATT was measured in both knees preoperatively and 6 months postoperatively using the KT-1000 arthrometer. The presence of associated meniscal and cartilage injuries was noted. Using multivariate analysis, Groups B, C, and D were compared with Group A, using this group as a reference.

RESULTS

A total of 10,957 patients were available in the register and 8502 (Group A n = 4335, Group B n = 3331, Group C n = 771, Group D n = 65) were included in the final analysis. Groups B (10.3 mm; 95% CI 0.06-0.042, p < 0.0001) and C (10.6 mm; 95% CI 0.23-0.89, p = 0.006) showed significantly greater preoperative ATT in the injured knee compared with the control group (10.1 mm). Moreover, at the 6-month follow-up, greater ATT was observed for Groups B (8.5 mm; 95% CI 0.13-0.45, p < 0.0001), C (8.5 mm; 95% CI 0.02-0.60, p = 0.035), and D (9.1 mm; 95% CI - 0.08-1.77, p = 0.082) compared with Group A (8.2 mm). Meniscal injuries were less frequent in patients with contralateral hyperextension [Group B 903 (27.1%) p < 0.0001, Group C 208 (27.0%) p = 0.0003, and Group D 12 (18.5%), 0.012] compared with the control group [Group A 1479 (34.1%)].

CONCLUSION

Contralateral knee hyperextension is associated with greater pre- and postoperative ATT in the ACL-injured knee. In patients with contralateral knee hyperextension, concomitant injuries to the menisci are less frequent. Surgeons should consider grafts with superior properties regarding postoperative anteroposterior laxity to patients with contralateral knee hyperextension.

LEVEL OF EVIDENCE

Retrospective cohort study, Level IV.

Collagen application reduces complication rates of mid-substance ACL tears treated with dynamic intraligamentary stabilization

PURPOSE

Dynamic intraligamentary stabilization was recently proposed as an option for the treatment of acute ACL ruptures. The aim of this study was to investigate the feasibility of the procedure in mid-substance ACL ruptures and examine whether the additional application of a bilayer collagen I/III membrane would provide for a superior outcome.

METHODS

The study group consisted of patients presenting with a mid-substance ACL rupture undergoing dynamic intraligamentary stabilization using the Ligamys™ device along with application of a collagen I/III membrane to the surface of the ACL (group A, n = 23). The control group comprised a matched series of patients presenting with a mid-substance ACL rupture also treated by dynamic intraligamentary stabilization Ligamys™ repair, however, without additional collagen application (group B, n = 33). Patients were evaluated preoperatively and at 24-month follow-up for stability as well as Tegner and Lysholm scores. Knee laxity was measured as a difference in anterior translation (ΔAP) and pivot shift. Any events occurring during the follow-up period of 24 months were documented. Logistic regression of complications was performed, and adjustment undertaken where necessary.

RESULTS

A high total complication rate of 78.8 % was noted in group B, compared to group A (8.7 %) (p = 0.002). The addition of a collagen membrane was the only independent prognostic factor associated with reduced complications (OR 8.0, CI 2.0-32.2, p = 0.003, for collagen-free treatment). In group B, 6 patients suffered a re-rupture with subsequent instability requiring secondary hamstring reconstruction surgery, and 11 developed extension loss requiring arthroscopic debridement, whilst in group A, 2 patients required arthroscopic debridement for loss of exension, with no further encountered complication. Median Lysholm score was significantly higher in group A compared to group B (median 100 range 93-100 vs median 95 range 60-100, p = 0.03) at final follow-up.

CONCLUSIONS

A high complication rate following ACL Ligamys™ repair of mid-substance ruptures was noted. Application of a collagen membrane to the surface of the ACL resulted in a reduced incidence of extension deficit and re-ruptures. The results indicate that solitary ACL Ligamys™ repair does not present an appropriate treatment modality for mid-substance ACL ruptures. Collage application proved to provide healing benefits with superior clinical outcome after ACL repair.

LEVEL OF EVIDENCE

Case control study, Level III.

Do graft diameter or patient age influence the results of ACL reconstruction?

PURPOSE

Hamstring tendons are commonly used as a graft source for ACL reconstruction. This study seeks to determine whether either the diameter of the tendon graft or the age of the patient influences the outcome of the ACL reconstruction when measured using a standard, previously validated laxity measurement device.

METHODS

This is a retrospective study of 88 patients who underwent ACL reconstruction with a short, quadrupled tendon technique, using the semitendinosus ± gracilis tendons. Patients included in this study were sequential, unilateral, complete ACL ruptures. The patients were followed for a minimum of 1 year postoperatively, with a mean follow-up of 26 months. Patients were divided into three groups according to the diameter (Ø) of the graft: group 1 (32 patients): 8 mm ≤ Ø ≤ 9 mm; group 2 (28 patients): 9 mm < Ø ≤ 10 mm; and group 3 (28 patients): Ø > 10 mm. Three groups with differential laxity at 134 N (Δ134 = healthy side vs. operated side) measured with the laximeter GNRB(®) were compared. The risk of residual laxity (OR) between the three groups taking age, gender, BMI and meniscus status into account was calculated. A side-to-side laxity >3 mm was considered as a residual laxity.

RESULTS

The mean patient age at the time of reconstruction was 29.4 years. The three groups were comparable. Postoperative Δ134 was 1.50 ± 1.3, 1.59 ± 1.5 and 2 ± 1.7 mm for groups 1 through 3, respectively. Δ134 > 3 mm was observed in three patients in group 1, four patients in group 2 and nine patients in group 3. As compared to group 1, OR was 1.46 (95 % CI 0.35-6.05) and 3.31 (95 % CI 0.89-12.34) in groups 2 and 3, respectively. Adjustment for age, gender, BMI and meniscus did not change the estimates [OR 1.44 (95 % CI 0.34-6.16) and 3.92 (95 % CI 1-15.37)] in groups 2 and 3, respectively. Patients younger than 20 had a significantly higher average postoperative laximetry (2.4 ± 1.5 mm) compared to those aged 20 years and over (1.5 ± 1.5 mm) (p = 0.03), regardless of the diameter of the graft.

CONCLUSION

The diameter of the graft between 8 and 10 mm does not affect the laximetric results of an ACL reconstruction. Therefore, there does not appear to be a benefit to harvesting and adding further tissue to increase the diameter of the graft above 10 mm. Patients younger than 20 represent a population at risk of graft elongation. In these patients at risk, postoperative management needs to be modified (delayed weight bearing, articulated splinting, slower rehabilitation) in the first months.

LEVEL OF EVIDENCE

Retrospective case series, Level IV.

Clinical Outcomes After Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction: Comparison of Extreme Knee Hyperextension and Normal to Mild Knee Hyperextension

PURPOSE

The aim of this study was to compare postoperative outcomes after anatomic double-bundle anterior cruciate ligament reconstruction (ACLR) in extreme knee hyperextension versus normal to mild knee hyperextension.

METHODS

For 100 patients who underwent anatomic double-bundle ACLR using semitendinosus tendon, we evaluated the side-to-side difference (SSD) in anterior tibial translation (measured on stress radiographs) and rotational stability (assessed by the pivot-shift test) 2 years after surgery. Loss of extension (LOE) was evaluated on lateral radiographs of both knees in full extension, and graft integrity was assessed during second-look arthroscopy 1 to 2 years after surgery. In accordance with the Beighton and Honan criteria, patients with an extension angle less than or equal to 10° in the contralateral uninjured knee composed the group with 10° or less hyperextension (N group), and those with an extension angle of greater than 10° composed the group with more than 10° hyperextension (H group). Postoperative results were compared between these groups.

RESULTS

Mean extension angles in the N and H groups were 5.8° ± 2.9° and 14.7° ± 3.0°, respectively. The mean SSD in anterior translation was 2.2 ± 2.9 mm for the N group and 2.8 ± 2.9 mm for the H group, with no significant difference. The positive ratios on the pivot-shift test were not significantly different between the groups. Mean LOE in the N and H groups was -0.7° ± 3.7° and 1.3° ± 3.3°, respectively, with a significant difference (P = .007). During second-look arthroscopy, 6 of 58 knees in the N group and 13 of 42 knees in the H group had superficial graft laceration of the anteromedial bundle graft, with a significant difference (P = .01) seen between groups.

CONCLUSIONS

Anatomic double-bundle ACLR for extreme knee hyperextension may attain the same postoperative anterior and rotational stability as seen in knees with normal to mild hyperextension. However, it increased superficial graft laceration.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Anatomic anterior cruciate ligament (ACL) reconstruction: a global perspective. Part 1

PURPOSE

In August 2011, orthopaedic surgeons from more than 20 countries attended a summit on anatomic anterior cruciate ligament (ACL) reconstruction. The summit offered a unique opportunity to discuss current concepts, approaches, and techniques in the field of ACL reconstruction among leading surgeons in the field.

METHODS

Five panels (with 36 panellists) were conducted on key issues in ACL surgery: anatomic ACL reconstruction, rehabilitation and return to activity following anatomic ACL reconstruction, failure after ACL reconstruction, revision anatomic ACL reconstruction, and partial ACL injuries and ACL augmentation. Panellists' responses were secondarily collected using an online survey.

RESULTS

Thirty-six panellists (35 surgeons and 1 physical therapist) sat on at least one panel. Of the 35 surgeons surveyed, 22 reported performing "anatomic" ACL reconstructions. The preferred graft choice was hamstring tendon autograft (53.1 %) followed by bone-patellar tendon-bone autograft (22.8 %), allograft (13.5 %), and quadriceps tendon autograft (10.6 %). Patients generally returned to play after an average of 6 months, with return to full competition after an average of 8 months. ACL reconstruction "failure" was defined by 12 surgeons as instability and pathological laxity on examination, a need for revision, and/or evidence of tear on magnetic resonance imaging. The average percentage of patients meeting the criteria for "failure" was 8.2 %.

CONCLUSIONS

These data summarize the results of five panels on anatomic ACL reconstruction. The most popular graft choice among surgeons for primary ACL reconstructions is hamstring tendon autograft, with allograft being used most frequently employed in revision cases. Nearly half of the surgeons surveyed performed both single- and double-bundle ACL reconstructions depending on certain criteria. Regardless of the technique regularly employed, there was unanimous support among surgeons for the use of "anatomic" reconstructions using bony and soft tissue remnant landmarks.