Femoral offset guide facilitates accurate and precise femoral tunnel placement for single-bundle anterior cruciate ligament reconstruction

Comparison of femoral tunnel position and knee function in anterior cruciate ligament reconstruction: a retrospective cohort study using measuring-fluoroscopy method versus bony marker method

BACKGROUND

Previous studies have shown that surgical technique errors especially the wrong bone tunnel position are the primary reason for the failure of anterior cruciate ligament (ACL) reconstruction. In this study, we aimed to compare the femoral tunnel position and impact on knee function during the ACL reconstruction using measuring combined with fluoroscopy method and bony marker method for femoral tunnel localization.

METHODS

A retrospective cohort study of patients undergoing ACL reconstruction using the bony marker method or measuring combined with fluoroscopy for femoral tunnel localization was conducted between January 2015 and January 2020. A second arthroscopic exploration was performed more than 1 year after surgery. Data regarding patient demographics, the femoral tunnel position, results of the Lysholm score, the International Knee Documentation Committee (IKDC) score, KT-1000 side-to-side difference, pivot shift grade, and Lachman grade of the knee were collected.

RESULTS

A total of 119 patients were included in the final cohort. Of these, 42 cases were in the traditional method group, and 77 cases were in the measuring method group. The good tunnel position rate was 26.2% in the traditional method group and 81.8% in the measuring method group (p < 0.001). At the final follow-up, the Lysholm and IKDC scores were significantly greater in the measuring method group than the traditional method group (IKDC: 84.9 ± 8.4 vs. 79.6 ± 6.4, p = 0.0005; Lysholm: 88.8 ± 6.4 vs. 81.6 ± 6.4, p < 0.001). Lachman and pivot shift grades were significantly greater in the measuring method group (p = 0.01, p = 0008). The results of KT-1000 side-to-side differences were significantly better in the measuring method group compared with those in the traditional method group (p < 0.001).

CONCLUSIONS

The combination of the measuring method and intraoperative fluoroscopy resulted in a concentrated tunnel position on the femoral side, a high rate of functional success, improved knee stability, and a low risk of tunnel deviation. This approach is particularly suitable for surgeons new to ACL reconstructive surgery.

Anterior cruciate ligament reconstruction learning curve study - Comparison of the first 50 consecutive patients of five orthopaedic surgeons during a 5-year follow-up

BACKGROUND

The goal of all surgical and orthopaedic training is to ensure necessary education and surgical skills without compromising the quality of operations or patient safety. Anterior cruciate ligament reconstruction (ACLR) is a common multi-staged orthopaedic surgical procedure with a learning curve. Previous studies focus mainly on learning or the learning curve of one surgeon and tunnel placements. The aims of this study were to define the learning curve in arthroscopic ACLRs, define the number of procedures needed before the surgical "knifetime" plateaus, examine the effect of experience on complications, and identify possible individual differences in the surgical learning curve.

METHODS

The study included the first 50 consecutive ACLR operations of five orthopaedic surgeons, thus, a total of 250 patients. For comparison and statistical analysis, patients were arranged into five groups, each comprising 50 patients (=order group). Order group 1 comprised the first 10 patients operated on by each of the five surgeons, group 2 patients 11-20, group 3 patients 21-30, group 4 patients 31-40, and group 5 the last 10 patients. The learning curve was defined with a LOESS curve. Surgical time and complications, including graft failure and postoperative knee instability, were analysed between order groups and between surgeons.

RESULTS

Median surgical time was 105 (interquartile range 82-124) min. The learning curve showed the first steep decline in surgical time and started to settle slowly after 20 reconstructions. Surgical time was significantly longer when order group 1 was compared with order group 2 (p = 0.031), and when order group 1 was compared separately with order groups 3, 4, and 5 (p < 0.001). Operation order alone explained only 17.1% of the alteration in surgical time. No significant difference emerged in graft failure rate between the order groups or the surgeons. Objective instability of the knee showed a significant difference when order group 1 was compared separately with order group 3 and with order group 4 (p = 0.004). Surgical time differed between surgeons (p < 0.001), and the shape of the learning curve showed great individual variability.

CONCLUSION

In the first 10 to 20 ACLR operations, the surgical time was longer and the complication rate higher, but thereafter both started to settle down. We recommend that first 10-20 ACLR operations should be supervised.

Freehand vs. Medial Portal Offset Aimer Technique for Accurate Femoral Tunnel Placement in Arthroscopic ACL Reconstruction

Purpose

In this study, our aim was to reveal the effect of the medial femoral offset aimer usage through the femoral tunnel entry and exit points and the tunnel length during femoral tunnel drilling in arthroscopic anterior cruciate ligament (ACL) reconstruction.

Methods

One hundred patients who underwent arthroscopic single-bundle ACL reconstruction were included in the study. Group 1 consisted of 50 patients who underwent femoral tunnel drilling using a medial portal offset aimer device, while Group 2 consisted of 50 patients who were operated on using the freehand technique. Both groups were compared in terms of femoral tunnel and graft tunnel lengths, femoral tunnel angle in the coronal plane, and the location of the femoral tunnel entry and exit points.

Results

The mean femoral tunnel and graft tunnel lengths were significantly longer in Group 2 (p = 0.000). There was no significant difference in terms of localization of the femoral tunnel entry point in both the axial and sagittal planes. The tunnel exit point was located significantly more posterior in Group 1 in the axial plane (p = 0.028). There was no significant difference in terms of the coronal plane femoral tunnel angle between the two groups.

Conclusion

In arthroscopic ACL reconstructions, more successful results may be obtained with the freehand technique compared to drilling with a femoral offset aimer. For an experienced orthopedic surgeon, using a medial portal offset aimer device during femoral tunnel drilling does not seem necessary.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-023-00929-z.

Distribution of bone tunnel positions and treatment efficacy of bone landmark positioning method for anatomical reconstruction of the anterior cruciate ligament: a case control study

BACKGROUND

This study aimed to investigate the distribution of femoral tunnel and explore the influences of bone tunnel positions on knee functions. The bone landmark positioning method was used to position the femoral tunnel during the anatomical reconstruction surgery in patients with anterior cruciate ligament (ACL) rupture.

METHODS

Data of patients who underwent anatomical reconstruction of the ACL between January 2015 and July 2018, were retrospectively analyzed. The distribution of the femoral tunnel was recorded on 3-D CT after surgery. The tunnel positions were classified into good and poor position groups based on whether the position was in the normal range (24-37% on the x-axis and 28-43% on the y-axis). The Lysholm and IKDC scores, KT-1000 side-to-side difference, pivot shift test and Lachman test results of the knee joints were recorded, and then the differences in knee joint functions between the two groups were analyzed.

RESULTS

84 eligible patients (84 knees) were finally included in this study. Twenty-two and 62 of the patients were categorized in the good and poor position groups, respectively, and the rate of good position was 26.2%. The distribution of bone tunnel was as follows: (x-axis) deep position in 10 patients (12%), normal position in 58 patients (69%), and shallow position in 16 patients (19%); (y-axis) high position in 54 patients (64%), normal position in 26 patients (31%), and low position in 4 patients (5%). 1 year later, the Lysholm and IKDC scores were significantly better in the good position group (P < 0.05), the KT-1000 side to side difference, the pivot shift test and Lachman test results were better in the good position group (P < 0.05).

CONCLUSIONS

The bone tunnels were found to be distributed in and beyond the normal range using the bone landmark method to position the femoral tunnel in the single-bundle anatomical reconstruction of ACL, while the rate of good bone tunnel position was low. The knee joint function scores and stability were lower in patients with poor position of the femoral tunnel.

Pediatric Revision Anterior Cruciate Ligament Reconstruction: Current Concepts Review

OBJECTIVE

We present a review of revision anterior cruciate ligament (ACL) reconstruction in pediatric patients, discussing risk factors for rerupture, physical examination and imaging, treatment principles and surgical techniques, postoperative rehabilitation, and clinical outcomes.

DATA SOURCES

PubMed, Cochrane, and Embase databases were queried for relevant articles about revision ACL topics. All types of manuscripts, including clinical studies, basic science studies, case series, current concepts reviews, and systematic reviews were analyzed for relevant information. Current concepts on risk factors for rerupture, physical examination and imaging, treatment principles and surgical techniques, postoperative rehabilitation, and clinical outcomes were synthesized.

MAIN RESULTS

Surgical treatment should be individualized, and the graft type, fixation devices, tunnel placement, and complementary procedures (eg, extra-articular tenodesis) should be tailored to the patient's needs and previous surgeries. Rehabilitation programs should also be centered around eccentric strengthening, isometric quadriceps strengthening, active flexion range of motion of the knee, and an emphasis on closed chain exercises. Despite adherence to strict surgical and postoperative rehabilitation principles, graft refailure rate is high, and return to sports rate is low.

CONCLUSION

Rerupture of the ACL in the pediatric population is a challenging complication that requires special attention. Diagnostic evaluation of repeat ACL ruptures is similar to primary injuries. Although outcomes after revision ACL reconstruction are expectedly worse than after primary reconstruction, athletes do return to sport after proper rehabilitation. Further research is needed to continue to improve outcomes in this high-risk population, aimed at continued knee stability, graft survivorship, and improved quality of life.

High variability in anterior cruciate ligament femoral footprint: Implications for anatomical anterior cruciate ligament reconstruction

BACKGROUND

The study aimed to (1) investigate the variability of the femoral ACL center in ACL-ruptured patients, (2) identify whether the currently available over-the-top femoral ACL guides could allow for anatomical reconstruction of the native ACL footprint.

MATERIAL AND METHODS

Magnetic resonance images of 95 knees with an ACL rupture were used to create three-dimensional models of the femur. The femoral ACL footprint area was outlined on each model, and the location of the femoral ACL center was reported using an anatomical coordinate system. The distance of the femoral ACL center from the over-the-top position was measured.

RESULTS

The femoral ACL center demonstrated a high intersubject variability ranging from 1.8 mm (9%) to 12.3 mm (60%) posterior and from 7.7 mm (37%) distal to 4.8 mm (23%) proximal using the posterior condyle circle reference. The average distance of the femoral ACL center from the over-the-top position was 1.9 ± 1.5 mm posterior and 13.8 ± 2.7 mm distal, respectively. The contemporary over-the-top femoral ACL aimers could restore the femoral ACL center in only 6.5% of the patients.

CONCLUSIONS

The femoral ACL center demonstrated a high variation on its location, which resulted in a high intersubject variability from the over-the-top position. The contemporary over-the-top femoral tunnel guides do not provide sufficient offset to allow for an anatomical ACL reconstruction. Anteromedial-portal specific femoral ACL guides with a femoral offset ranging from 10 to 18 mm in the proximal/distal direction are required to restore the native ACL footprint.

Positioning Technique of the Fixed Knee in Hyperflexion for the Transportal Femoral Tunnel During Reconstruction of the Anterior Cruciate Ligament

During reconstruction surgery of the anterior cruciate ligament, the evolution of the femoral tunnel from the transtibial to the transportal path provides greater accuracy in reaching the desired anatomic point. However, there are also some new challenges, such as correct execution, reproducibility, and minimizing the risk of iatrogenic injury from its use. In an effort to overcome these challenges, we have proposed the use of a positioner, which was developed by our group and allows the leg to stay in the desired position, without variations in the operation or aid from a medical assistant. This manuscript presents our femoral tunnel preparation technique and its application in clinical practice.