Anatomic anterior cruciate ligament reconstruction utilizing the double-bundle technique

Changes in co-contraction magnitude during functional tasks following anterior cruciate ligament reconstruction: A systematic review

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) is a common orthopedic surgery procedure whose incidence has increased over the past few decades. Nevertheless, it is believed that neuromuscular control remains altered from the early stages after ACLR to later years. Therefore, the aim of this study was to systematically evaluate the magnitude of co-contraction during functional tasks in subjects with unilateral ACLR.

METHODS

A systematic review design was followed. The search strategy was conducted in PubMed, Scopus, EBSCO, PEDro, Cochrane Library, and Web of Science databases from inception to March 2024. The inclusion criteria involved studies using electromyography (EMG) data to calculate muscle pair activation via the co-contraction index (CCI) in ACLR individuals during functional tasks. The Preferred Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed, and study quality was evaluated using National Institutes of Health (NIH) Study Quality Assessment Tools.

RESULTS

The search strategy found a total of 792 studies, of which 15 were included in this systematic review after reviewing the eligibility criteria. The magnitude of co-contraction was assessed in a total of 433 ACLR individuals and 206 controls during functional tasks such as hop, drop-land, step-up/step-down, and gait. Overall, approximately 79.6% of individuals who had undergone ACLR exhibited increased levels of co-contraction magnitude in the ACLR limb, while 8.5% showed low co-contraction levels.

CONCLUSIONS

The findings of the review suggest that, during functional tasks, most individuals who have undergone ACLR exhibit changes of co-contraction magnitude in the involved limb.

U-Dos Double-Bundle and Single-Bundle Allograft Anterior Cruciate Ligament Reconstruction: A Comparative Study

Anterior cruciate ligament (ACL) injuries are very common among athletes. If these injuries are not repaired, meniscus and cartilage damage will arise, with serious consequences in the joint. Different options for ACL reconstruction have been described, aiming for anteroposterior, lateral, and rotational stability. Using single- or double-bundle grafts has been one of the most discussed topics, aiming for better rotational stability. We performed a prospective randomized study to evaluate the outcomes of ACL reconstruction using double- or single-bundle grafts for 72 patients with acute ACL injuries. Patients were blindly randomized into 2 groups of 36 knees before surgery using a blind envelope that contained the technique to be used: double-bundle U-Dos technique (DB group) or single-bundle technique (SB group). All patients had a preoperative and postoperative evaluation and were followed with the same parameters at 2, 4, 6, 12, and 24 months. Both anteroposterior and rotational stability were evaluated using a KT-1000 arthrometer (MEDmetric) and an experimental Pivot-Shift Meter (ORMEDS) device. Functional outcomes were measured using the Tegner-Lysholm scale. The DB group had fewer ACL re-tears, fewer meniscal injuries, and better Tegner-Lysholm and International Knee Documentation Committee scores. This group also had better KT-1000 and Pivot-Shift Meter values. After 2-year follow-up, the DB group had significantly better results than the SB group. [Orthopedics. 2023;46(1):13-18.].

Computer-assisted navigation in ACL reconstruction improves anatomic tunnel placement with similar clinical outcomes

BACKGROUND

While the use of navigation systems in anterior cruciate ligament (ACL) reconstruction theoretically improves tunnel placement accuracy and clinical outcomes, the existing literature remains inconclusive. We aimed to evaluate the potential benefits of navigated ACL reconstruction on tunnel placement and clinical outcomes.

METHODS

In this retrospective study, we evaluated a cohort of patients who underwent conventional or navigated (OrthoPilot system) primary ACL reconstruction at our institution from June 2004 to October 2009. Anteroposterior and lateral radiographic knee assessments were evaluated to assess postoperative tunnel positioning. Clinical outcomes, including the International Knee Documentation Committee classification, Lysholm score, and Tegner score, were evaluated preoperatively and 1-year postoperatively. Radiographic and clinical outcomes were compared and analysed using independent 2-sample t-tests and Chi-square tests.

RESULTS

Sixty patients met the inclusion criteria and were included for analysis, comprising of 26 navigated and 34 conventional reconstructions. Postoperative radiographs showed no differences in tibial tunnel position between both groups, but a significantly smaller deviation from the recommended position in the navigated group (navigated: 5.96 %; conventional: 7.92 %; p = 0.008). Femoral tunnel placements in the navigated group were significantly more perpendicularly away from the Blumensaat line (navigated: 38.90 %; conventional: 31.94 %; p = 0.001), with a greater deviation from recommended position (navigated: 11.00 %; conventional: 6.94 %; p = 0.009). There were no differences in 1-year postoperative clinical outcomes (p > 0.05).

CONCLUSION

Navigated ACL reconstruction resulted in a more anatomic femoral tunnel placement and similar clinical outcomes as conventional reconstruction. Further research should be conducted to clarify the potential biomechanical and clinical impacts of navigated ACL reconstruction.

Establishment of near and non isometric anterior cruciate ligament reconstruction with artificial ligament in a rabbit model

Background

Tunnel position deicide the isometry of graft attachment in synthetic anterior cruciate ligament (ACL) reconstruction. Near-isometric tunnel position may have advantage in graft integration and knee function in ACL reconstruction (ACLR) with polyethylene terephthalate (PET) ligament. Few studies focused on tunnel position isometry when conduct ACLR with an animal model. This study aimed to establish a preclinical rabbit model of near and non isometric ACLR with PET ligament and investigate the advantage of near-isometric ACLR compared to non-isometric ACLR.

Methods

Nine hind limbs of rabbit were used in tunnel position study. Two femoral(anatomic, nonanatomic) tunnels and three tibial(anterior, middle, posterior) tunnels were used to measure tunnel position isometry during knee full range of motion. The tunnel position combination with minimal isometry was considered as near-isometric tunnel position. Then, 48 rabbits divided into two groups were conducted near or non isometric ACLR with PET ligament with graft fixation angle of 30° and constant tension of 5N. PET ligament isometry, range of motion(ROM) restriction, knee laxity were recorded after operation and followed up with macroscopic observation, microcomputed tomography (micro-CT) analysis, histology assessment and biomechanical test at 4 and 8 weeks postoperatively.

Results

The tunnel combination with minimal isometry was femoral anatomic position and tibial posterior position(5.19 ​± ​1.78%) and considered as near-isometric tunnel position. ROM restriction were observed in non-isometric group (22.50 ​± ​14.14°) while none in near-isometric group. However, no ROM restriction observed at 8 weeks in both group. Knee laxity compared to contralateral knee were better in near-isometric group than non-isometric group (stable/slack/total 10/2/12 VS 3/9/12, p ​= ​0.012) at 8 weeks postoperatively. Supeiror PET ligament integration were also observed in near-isometric group through macroscopic observation, micro-CT analysis, histology assessment at both 4 and 8 weeks. The failure load in the Near-Isometric group at 8 weeks were higher than timezero reconstruction with statistical difference (156.8N ​± ​25.98N vs.102.6 ​± ​22.96N, p ​= ​0.02).

Conclusion

A rabbit model of ACLR based on tunnel position isometry was successfully established in this study. The near-isometric tunnel position in rabbit model was femoral anatomic position and tibial posterior position. A near-isometric ACLR with PET ligament did not cause ROM restriction and had a better graft integration and follow-up stability than non-isometric ACLR with ROM restriction.

The Translational Potential of this Article

The study demonstrate the establishmentof near-isometric tunnel position and non-isometric tunnel position with significant difference of ROM restriction and graft-bone integration. The described tunnel positions with differential isometry in a rabbit ACLR provides a reproducible and translational small animal model and enables preclinical research between tunnel position isometry and its affection on variable grafts, graft integration and knee function.

No Difference in Ligamentous Strain or Knee Kinematics Between Rectangular or Cylindrical Femoral Tunnels During Anatomic ACL Reconstruction With a Bone-Patellar Tendon-Bone Graft

BACKGROUND

As our understanding of anterior cruciate ligament (ACL) anatomy has evolved, surgical techniques to better replicate the native anatomy have been developed. It has been proposed that the introduction of a rectangular socket ACL reconstruction to replace a ribbon-shaped ACL has the potential to improve knee kinematics after ACL reconstruction.

PURPOSE

To compare a rectangular femoral tunnel (RFT) with a cylindrical femoral tunnel (CFT) in terms of replicating native ACL strain and knee kinematics in a time-zero biomechanical anatomic ACL reconstruction model using a bone-patellar tendon-bone (BTB) graft.

STUDY DESIGN

Controlled laboratory study.

METHODS

In total, 16 fresh-frozen, human cadaveric knees were tested in a 5 degrees of freedom, computed tomography-compatible joint motion simulator. Knees were tested with the ACL intact before randomization to RFT or CFT ACL reconstruction using a BTB graft. An anterior translation load and an internal rotation moment were each applied at 0°, 30°, 60°, and 90° of knee flexion. A simulated pivot shift was performed at 0° and 30° of knee flexion. Ligament strain and knee kinematics were assessed using computed tomography facilitated by insertion of zirconium dioxide beads placed within the substance of the native ACL and BTB grafts.

RESULTS

For the ACL-intact state, there were no differences between groups in terms of ACL strain or knee kinematics. After ACL reconstruction, there were no differences in ACL graft strain when comparing the RFT and CFT groups. At 60° of knee flexion with anterior translation load, there was significantly reduced strain in the reconstructed state ([mean ±standard deviation] CFT native, 2.82 ± 3.54 vs CFT reconstructed, 0.95 ± 2.69; RFT native, 2.77 ± 1.71 vs RFT reconstructed, 1.40 ± 1.76) independent of the femoral tunnel type. In terms of knee kinematics, there were no differences when comparing the RFT and CFT groups. Both reconstructive techniques were mostly effective in restoring native knee kinematics and ligament strain patterns as compared with the native ACL.

CONCLUSION

In the time-zero biomechanical environment, similar graft strains and knee kinematics were achieved using RFT and CFT BTB ACL reconstructions. Both techniques appeared to be equally effective in restoring kinematics associated with the native ACL state.

CLINICAL RELEVANCE

These data suggest that in terms of knee kinematics and graft strain, there is no benefit in performing the more technically challenging RFT as compared with a CFT BTB ACL reconstruction.

Pain Following Single-bundle versus Double-bundle Anterior Cruciate Ligament Reconstruction: A Systematic Review

BACKGROUND: Double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) has been known to result in better functional outcomes, joint stability, and lower revision rates compared to single-bundle (SB) ACLR. However, given the increased invasiveness and damage to the surrounding tissue area, it is proposed that it may be associated with increased pain. AIM: This review aims to gather all studies and literature that reported pain as an outcome when comparing SB versus DB ACLR. METHODS: Literature searching was conducted across seven search engines for studies reporting pain as an outcome and comparing SB versus DB ACLR. RESULTS: Eight studies met the eligibility criteria and were included in the study. Overall, the studies show variable findings regarding pain in DB compared to SB ACLR, with the only statistically significant results from two studies indicating that DB ACLR is associated with more pain than SB ACLR. CONCLUSION: Based on the limited evidence available, no conclusions can be made regarding the pain experienced between people receiving either procedure. This constitutes a need for additional studies with increased follow-up time periods, larger sample size, and better study design.

[Effectiveness of double-bundle anterior cruciate ligament reconstruction combined with anterolateral ligament reconstruction for revision]

Objective

To investigate the effectiveness of double-bundle anterior cruciate ligament (ACL) reconstruction combined with anterolateral ligament (ALL) reconstruction in the treatment of revision patients with ACL graft failure.

Methods

Between January 2018 and June 2019, 15 patients underwent ACL revision with double-bundle ACL reconstruction combined with ALL reconstruction. There were 12 males and 3 females with an average age of 30.1 years (range, 17-49 years). The technique of primary ACL reconstruction included single-bundle reconstruction in 13 cases and double-bundle reconstruction in 2 cases. These reconstructions applied autografts in 14 cases and allograft in 1 case. The causes of ACL reconstruction failure were identified as traumatic rupture in 9 cases and non-traumatic failure in 6 cases, including 2 cases of graft absorption and 3 cases of graft laxity. The average time from the primary ACL reconstruction to revision was 28.5 months (range, 8-60 months). The subjective and objective indicators of knee joint function were compared before operation and at last follow-up to evaluate the effectiveness. The subjective indicators included International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner score. The objective indicators included anterior tibial translation (dynamic and static) and side-to-side difference (SSD), pivot-shift test, Lachman test, the difference of single-legged hop test, and the loss ratio of extensor muscle strength on the affected side.

Results

All incisions healed by first intetion, and no complications such as infection, venous thrombosis of lower extremity, or neurovascular injury occurred. All patients were followed up for an average of 19.1 months (range, 12-30 months). At last follow-up, all patients had returned to pre-injury sports level. The IKDC score, Lysholm score, and Tegner score were significantly improved ( P<0.05); anterior tibial translations (dynamic and static) significantly decreased when compared with preoperative one ( P<0.05) and returned to the physiological range. The SSD, Lachman test, pivot-shift test, the difference of single-legged hop test, and the loss ratio of extensor muscle strength on the affected side were significantly better than those before operation ( P<0.05).During the follow-up, there was no re-rupture of the graft, no stiffness of the knee joint and limitation of mobility; 1 case had a protruding femoral end compression screw, which was removed through the original incision under local anesthesia.

Conclusion

Double-bundle ACL reconstruction combined with ALL reconstruction can significantly improve the knee function in revision patients with ACL graft failure. It can reduce the anterior translation of tibia, and effectively prevent postoperative rotational instability of the knee.

Over-the-Top Anterior Cruciate Ligament Reconstruction Using Single- or Double-Strand Hamstrings Autograft

The purpose of this study is to (1) report the long-term clinical and radiographic outcomes of a nonanatomical anterior cruciate ligament (ACL) reconstruction using an over-the-top (OTT) femoral route and (2) compare single-strand (1SHG) and double-strand (2SHG) hamstrings graft reconstruction. Fifty-one consecutive patients (mean age, 29.2±3.8 years) underwent nonanatomical ACL reconstruction using OTT femoral passage. Twenty patients underwent 1SHG reconstruction and 31 underwent 2SHG reconstruction. International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), Tegner score, and KT-1000 (Medmetric Corporation, San Diego, California) evaluation were recorded at a mean follow-up of 12.1±1.6 years. At final follow-up, radiographic evaluation was performed according to the IKDC grading system. Mean IKDC subjective score at follow-up was 76.6±21.9 in the 1SHG group and 88.9±10.0 in the 2SHG (P=.009). Average KOOS was 82.6±18.7 in the 1SHG group and 92.4±9.2 in the 2SHG group (P=.016). Objective IKDC evaluation showed a higher percentage of normal knees in the 2SHG group (P=.018). Pivot shift testing revealed a significantly higher number of normal knees in the 2SHG group (P=.001). Radiographs showed fewer degenerative changes in the 2SHG group at final follow-up in the medial (P=.01) and lateral (P=.037) compartments. Nonanatomical ACL reconstruction using the OTT technique provided satisfactory results in terms of control of both static and dynamic instability at long-term follow-up, thus preventing degenerative joint disease. The 2SHG group showed better subjective and functional outcomes with fewer degenerative changes compared with the 1SHG group at long-term follow-up.

Features extraction in anterior and posterior cruciate ligaments analysis

The main aim of this research is finding the feature vectors of the anterior and posterior cruciate ligaments (ACL and PCL). These feature vectors have to clearly define the ligaments structure and make it easier to diagnose them. Extraction of feature vectors is obtained by analysis of both anterior and posterior cruciate ligaments. This procedure is performed after the extraction process of both ligaments. In the first stage in order to reduce the area of analysis a region of interest including cruciate ligaments (CL) is outlined in order to reduce the area of analysis. In this case, the fuzzy C-means algorithm with median modification helping to reduce blurred edges has been implemented. After finding the region of interest (ROI), the fuzzy connectedness procedure is performed. This procedure permits to extract the anterior and posterior cruciate ligament structures. In the last stage, on the basis of the extracted anterior and posterior cruciate ligament structures, 3-dimensional models of the anterior and posterior cruciate ligament are built and the feature vectors created. This methodology has been implemented in MATLAB and tested on clinical T1-weighted magnetic resonance imaging (MRI) slices of the knee joint. The 3D display is based on the Visualization Toolkit (VTK).

Usefulness of oblique coronal and sagittal MR images of the knee after double-bundle and selective anterior cruciate ligament reconstructions

BACKGROUND

The use of double-bundle and selective-bundle anterior cruciate ligament (ACL) reconstruction is increasing. Few studies have been conducted to determine the diagnostic efficacy of additional oblique views of knee magnetic resonance imaging (MRI) for grading ACL graft injury for double-bundle and selective-bundle ACL reconstructions.

PURPOSE

To evaluate the diagnostic value of combining oblique coronal and sagittal imaging with orthogonal views for diagnosis of ACL graft failure after double-bundle or selective-bundle ACL reconstruction.

MATERIAL AND METHODS

This retrospective study included 64 patients who underwent double-bundle or selective-bundle ACL reconstruction surgery and received oblique coronal and oblique sagittal MRI of the knee. Subjective scoring of the images was performed by two radiologists who assessed the possibility of ACL graft failure based on full length view, full width view, and margin sharpness according to a 4-point scale. Diagnostic performance for ACL graft failure based on orthogonal views alone, ACL views alone, and orthogonal views with additional ACL views was evaluated by calculating the sensitivity, specificity, and accuracy.

RESULTS

The full length scores and total scores on ACL views were significantly higher than those of orthogonal views. The specificities and accuracies of diagnoses were highest for a combination of orthogonal, ACL sagittal, and ACL coronal views.

CONCLUSION

After double-bundle or selective-bundle ACL reconstruction, oblique sagittal and coronal images of the ACL provide better anatomic evaluation of the ACL than orthogonal views and specificity and accuracy of diagnoses were improved when oblique views were combined.

A comparison of pain scores and medication use in patients undergoing single-bundle or double-bundle anterior cruciate ligament reconstruction

BACKGROUND

No gold standard exists for the management of postoperative pain following anterior cruciate ligament reconstruction (ACLR). We compared the pain scores and medication use of patients undergoing single-bundle (SB) or double-bundle (DB) ACLR in the acute postoperative period. Pain and medication use was also analyzed for spinal versus general anesthesia approaches within both surgery types.

METHODS

We assessed 2 separate cohorts of primary ACLR patients, SB and DB, for 14 days postoperatively. We used a standard logbook to record self-reported pain scores and medication use. Pain was assessed using a 100 mm visual analogue scale (VAS). Medications were divided into 3 categories: oral opioids, oral nonsteroidal anti-inflammatories and acetaminophen.

RESULTS

A total of 88 patients undergoing SB and 41 undergoing DB ACLR were included in the study. We found no significant difference in VAS pain scores between the cohorts. Despite similar VAS pain scores, the DB cohort consumed significantly more opioid and analgesia medication (p = 0.011). Patients who underwent DB with spinal anesthesia experienced significantly less pain over the initial 14-day postoperative period than those who received general anesthesia (p < 0.001).

CONCLUSION

Adequate pain relief was provided to all ACLR patients in the initial postoperative period. Patients in the DB cohort experienced more pain, as evidenced by the significant diffrence in consumption of opioids and acetaminophen, than the SB cohort. Patients who underwent spinal anesthesia experienced less pain in the acute postoperative period than those who received general anesthesia.

Operative treatment of primary anterior cruciate ligament rupture in adults

Operative management of an acute anterior cruciate ligament (ACL) rupture may be required in young and active patients to stabilize the knee and return patients to desired daily activities. ACL reconstruction should be performed anatomically. The majority of studies show no differences between anatomic single-bundle and double-bundle ACL reconstruction with respect to patient-reported outcome scores. Double-bundle reconstruction may provide superior knee joint laxity measurements compared with the single-bundle technique. Following ACL reconstruction, the age and activity level of a patient are predictive of his or her time of return to sports and reinjury. Concomitant meniscal and/or cartilage damage at the time of surgery, in addition to a persistent knee motion deficit, are associated with the development of osteoarthritis after ACL reconstruction.

Gait analysis of anterior cruciate ligament reconstructed subjects with a combined tendon obtained from hamstring and peroneus longus

BACKGROUND

Stability of the knee joint is achieved by a complex process in which the anterior cruciate ligament (ACL) plays an important role. The rupture of this ligament is quite frequent especially in athletic young subjects. Various methods have been used to reconstruct the ACL. One of the new methods is to use a graft combined from peroneus longus and hamstring. As there is no evidence regarding this method, it was aimed to evaluate the efficiency of this method.

METHOD

Two groups of normal and those with ACL injury, in whom their ACLs were reconstructed with the new method, participated in this study. The kinematic and kinetic parameters during walking on level surface were evaluated by a motion analysis system (Qualysis) and a Kistler force plate. The difference between the parameters of operated and non-operated sides and also between patients and normal subjects was evaluated by use of a two sample t test (p-value was 0.05).

RESULTS

The results of this study showed that the pattern and magnitude of the loads transmitted by lower extrimity joints differed between normal and ACL reconstructed subjects. The sound side pattern and magnitude of motion were also influenced by ACL insufficiency.

CONCLUSIONS

The results of the current study showed that the reconstructed ACL by use of this method did not have enough performance to restore the function of the leg. As the knee joint is unstable following the use of this method, it is recommended to find a new method of ACL reconstruction to improve the function of this ligament after reconstruction.

The shape and the thickness of the anterior cruciate ligament along its length in relation to the posterior cruciate ligament: a cadaveric study

PURPOSE

The purpose of this study was to evaluate the shape of the native anterior cruciate ligament (ACL) along its length in relation to the posterior cruciate ligament (PCL) and compare it with the size of the 3 commonly used autografts (bone-patellar tendon-bone [BPTB], single-bundle hamstring, and double-bundle hamstring).

METHODS

With the knee in extension, we filled the intercondylar notch with paraffin, fixing the cruciate ligaments in their natural position, in 8 cadaveric specimens. The ACL-PCL tissue specimen, embedded in paraffin, was removed en bloc. Gross sections were prepared in the coronal plane and were evaluated histologically. The width, thickness, and cross-sectional area of both the ACL and PCL were determined. The dimensions of the semitendinosus tendon (ST), gracilis tendon (GT), and BPTB grafts were measured and compared with those of the native ACL.

RESULTS

The PCL occupies the largest part of the intercondylar area, leaving only a small space for the ACL in knee extension. The ACL midsubstance has a width of 5 mm, resembling a band shape. Only before its tibial insertion does the ACL fan out and take the form of its tibial attachment. The BPTB graft has a thickness of 5.8 mm, whereas the ST and GT grafts have a thickness of 6.25 mm and 4.5 mm, respectively, and are comparable to the midsubstance of the ACL but undersized in the tibial insertion (P = .0016 for BPTB graft, P = .002 for ST graft, and P = .0003 for GT graft). A quadruple-looped ST-GT graft, with a diameter of 8 mm, is oversized in the midsubstance (P = .0002) but fits better in the tibial attachment.

CONCLUSIONS

The ACL midsubstance has a width of 5 mm, resembling a band shape. Before its tibial insertion, the ACL fans out like a trumpet, taking the form of its wide tibial attachment.

CLINICAL RELEVANCE

The dimensions of the native ACL have to be considered in graft selection for anatomic ACL reconstruction.

Anatomic double-bundle reconstruction techniques result in graft obliquities that closely mimic the native anterior cruciate ligament anatomy

BACKGROUND

It has been reported previously that single-bundle anterior cruciate ligament (ACL) reconstruction with more accurate restoration of the footprint of the native ACL fails to restore the graft obliquity of the native ACL in the coronal plane. Whether double-bundle ACL reconstruction restores the graft obliquity of each bundle of the native ACL has not yet been determined.

HYPOTHESIS

Anatomic double-bundle ACL reconstruction using transportal (TP) and outside-in (OI) techniques can restore the graft obliquities of both anteromedial (AM) and posterolateral (PL) bundles in the native ACL in both sagittal and coronal planes.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Seventy-six patients underwent anatomic double-bundle ACL reconstruction. Patients were randomized to 2 groups to undergo either TP or OI tibial tunnel-independent anatomic ACL reconstruction. All participants underwent postoperative magnetic resonance imaging of both knees, and the native ACL obliquity was determined using the participant's contralateral knee. Graft obliquities were determined by measuring the angles between the center line of the graft and the surface line of the tibial plateau, and the obliquities of paired knees were compared. Graft obliquities were analyzed in each group.

RESULTS

In the sagittal plane, the mean AM graft obliquity was 54.2° on the operated side and 54.6° on the nonoperated side, and the difference between sides was not statistically significant (P = .352). The mean PL graft obliquity in the sagittal plane was 54.1° on the operated side and 53.0° on the nonoperated side, and the difference between sides was also not statistically significant (P = .228). In the coronal plane, the mean AM graft obliquity was 73.8° on the operated side and 73.4° on the nonoperated side, and the mean PL graft obliquity was 65.5° on the operated side and 66.4° on the nonoperated side. There were no statistically significant differences between sides (P = .418 for AM graft; P = .328 for PL graft). Differences in the paired graft obliquities in each group were also statistically insignificant between the TP and OI groups.

CONCLUSION

Both TP and OI anatomic double-bundle reconstruction techniques can result in graft obliquities in both bundles that resemble the native ACL in both sagittal and coronal planes.

CLINICAL RELEVANCE

Double-bundle ACL reconstruction techniques might more closely restore the normal kinematics of the native ACL by restoring the normal obliquity of both ACL bundles.

Open kinetic chain exercises in a restricted range of motion after anterior cruciate ligament reconstruction: a randomized controlled clinical trial

BACKGROUND

Recent studies have shown that an early start of open kinetic chain (OKC) exercises for quadriceps strengthening in a full range of motion (ROM) could increase anterior knee laxity after anterior cruciate ligament (ACL) reconstruction with flexor tendons. However, there are no clinical trials that evaluated outcomes of OKC exercises in a restricted ROM for pain, function, muscle strength, and anterior knee laxity at 1 year after surgery.

PURPOSE

To determine if an early start of OKC exercises for quadriceps strength in a restricted ROM would promote a clinical improvement without causing increased anterior knee laxity in patients after ACL reconstruction.

STUDY DESIGN

Randomized controlled clinical trial; Level of evidence, 1.

METHODS

A total of 49 patients between 16 and 50 years of age who underwent ACL reconstruction with semitendinosus and gracilis autografts were randomly assigned to an early start OKC (EOKC) exercise group or a late start OKC (LOKC) exercise group. The EOKC group (n = 25; mean age, 26 years) received a rehabilitation protocol with an early start of OKC (fourth week postoperatively) within a restricted ROM between 45° and 90°. The LOKC group (n = 24; mean age, 24 years) performed the same protocol with a late start of OKC exercises between 0° and 90° (12th week postoperatively). Quadriceps and hamstring muscle strength, 11-point numerical pain rating scale (NPRS), Lysholm knee scoring scale, single-legged and crossover hop tests, and anterior knee laxity were measured to assess outcomes at the 12-week, 19-week, 25-week, and 17-month postoperative follow-up (range, 13-24 months).

RESULTS

No difference (P < .05) was noted between groups with respect to demographic data. Both groups (EOKC and LOKC) had a higher level of function and less pain at the 19-week, 25-week, and 17-month assessments when compared with 12 weeks postoperatively (P < .05). The EOKC group had improved quadriceps muscle strength at the 19-week, 25-week, and 17-month follow-up when compared with 12 weeks postoperatively (P < .05); the LOKC group showed improvement only at the 17-month postoperative assessment. However, the analysis between groups showed no difference for all pain and functional assessments, including anterior knee laxity (P > .05).

CONCLUSION

An early start of OKC exercises for quadriceps strengthening in a restricted ROM did not differ from a late start in terms of anterior knee laxity. The EOKC group reached the same findings in relation to pain decrease and functional improvement when compared with the LOKC group but showed a faster recovery in quadriceps strength. The nonweightbearing exercises seem appropriate for patients who have undergone ACL reconstruction, when utilized in a specific ROM. The magnitude of difference in quadriceps strength between the 2 rehabilitation protocols was around 5%; however, this difference was not clinically significant, especially because both groups had equal function on the hop tests.

Relationship of the intercondylar roof and the tibial footprint of the ACL: implications for ACL reconstruction

BACKGROUND

Debate exists on the proper relation of the anterior cruciate ligament (ACL) footprint with the intercondylar notch in anatomic ACL reconstructions. Patient-specific graft placement based on the inclination of the intercondylar roof has been proposed. The relationship between the intercondylar roof and native ACL footprint on the tibia has not previously been quantified.

HYPOTHESIS

No statistical relationship exists between the intercondylar roof angle and the location of the native footprint of the ACL on the tibia.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Knees from 138 patients with both lateral radiographs and MRI, without a history of ligamentous injury or fracture, were reviewed to measure the intercondylar roof angle of the femur. Roof angles were measured on lateral radiographs. The MRI data of the same knees were analyzed to measure the position of the central tibial footprint of the ACL (cACL). The roof angle and tibial footprint were evaluated to determine if statistical relationships existed.

RESULTS

Patients had a mean ± SD age of 40 ± 16 years. Average roof angle was 34.7° ± 5.2° (range, 23°-48°; 95% CI, 33.9°-35.5°), and it differed by sex but not by side (right/left). The cACL was 44.1% ± 3.4% (range, 36.1%-51.9%; 95% CI, 43.2%-45.0%) of the anteroposterior length of the tibia. There was only a weak correlation between the intercondylar roof angle and the cACL (R = 0.106). No significant differences arose between subpopulations of sex or side.

CONCLUSION

The tibial footprint of the ACL is located in a position on the tibia that is consistent and does not vary according to intercondylar roof angle. The cACL is consistently located between 43.2% and 45.0% of the anteroposterior length of the tibia. Intercondylar roof-based guidance may not predictably place a tibial tunnel in the native ACL footprint. Use of a generic ACL footprint to place a tibial tunnel during ACL reconstruction may be reliable in up to 95% of patients.

The use of intra-operative fluoroscopy for tibial tunnel placement in anterior cruciate ligament reconstruction

OBJECTIVES

Our aim was to assess the use of intra-operative fluoroscopy in the assessment of the position of the tibial tunnel during reconstruction of the anterior cruciate ligament (ACL).

METHODS

Between January and June 2009 a total of 31 arthroscopic hamstring ACL reconstructions were performed. Intra-operative fluoroscopy was introduced (when available) to verify the position of the guidewire before tunnel reaming. It was only available for use in 20 cases, due to other demands on the radiology department. The tourniquet times were compared between the two groups and all cases where radiological images lead to re-positioning of the guide wire were recorded. The secondary outcome involved assessing the tibial interference screw position measured on post-operative radiographs and comparing with the known tunnel position as shown on intra-operative fluoroscopic images.

RESULTS

Of the 20 patients treated with fluoroscopy, the imaging led to repositioning of the tibial guide wire before reaming in three (15%). The mean tourniquet time with intra-operative fluoroscopy was 56 minutes (44 to 70) compared with 51 minutes (42 to 67) for the operations performed without. Six patients (30%) had post-operative screw positions that were > 5% more posterior than the known position of the tibial tunnel.

CONCLUSION

Intra-operative fluoroscopy can be effectively used to improve the accuracy of tibial tunnel positions with minimal increase in tourniquet time. This study also demonstrates the potential inaccuracy associated with plain radiological assessment of tunnel position.