Biomechanical Assessment of the Reconstruction of the Anterolateral Ligament During ACL Surgery. The In-Vivo Study

Biomechanical Assessment of the Reconstruction of the Anterolateral Ligament During ACL Surgery. The In-Vivo Study

2017 ISAKOS ABSTRACTS Conclusion: We suggest that the potential influence of the ALL on knee stability should be further investigated before performin...

278KB Sizes 188 Downloads 131 Views

2017 ISAKOS ABSTRACTS

Conclusion: We suggest that the potential influence of the ALL on knee stability should be further investigated before performing routine ALL reconstruction. Anterolateral knee ligament may have little impact on rotational laxity when iliotibial band is preserved. Category: Knee - ACL Paper #238: The Impact of the Anterolateral Capsule Injury on the Rotational Laxity in the Anterior Cruciate Ligament InjuredKnees. A Result of Clinical Quantitative Evaluation of the Pivot-Shift Test NOBUAKI MIYAJI, MD, JAPAN YUICHI HOSHINO, MD, PHD, JAPAN KAZUYUKI IBARAKI, MD, JAPAN TOSHIKAZU TANAKA, MD, JAPAN KYOHEI NISHIDA, MD, JAPAN YUICHIRO NISHIZAWA, MD, JAPAN DAISUKE ARAKI, MD, PHD, JAPAN NORIYUKI KANZAKI, MD, PHD, JAPAN TAKEHIKO MATSUSHITA, MD, JAPAN RYOSUKE KURODA, MD, PHD, JAPAN Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, Hyogo, JAPAN

SUMMARY The impact of the anterolateral capsule (ALC) injury on the rotational laxity in the ACL-injured knees was tested using a quantitative evaluation of the pivot-shift test in 82 clinical cases, and the measurements were compared between the ACL-injured knees with and without the ALC injury determined by MRI. As a result, the ALC injury did not worsen the rotational laxity in the ACL-injured knees. ABSTRACT DATA Purpose: The potential impact of the anterolateral capsule (ALC) injury on the rotational laxity in the anterior cruciate ligament (ACL) injured-knees has been suggested by some basic in-vitro studies, however most of such studies utilized their original rotational stress test rather than the clinically-used pivot-shift test. The pivotshift test might be difficult to be simulated by applying a complex rotational stress but is exclusively specific to evaluate the rotational laxity. There are some quantitative measurement devices for the pivot-shift test which can be used in our clinical practice. The purpose of this study was to quantitatively evaluate the pivot-shift test in clinical cases and compared them between ACL injured-knees with and without the ALC injury determined by MRI. Methods: There were 82 patients (38 males and 44 females, age 25.1  11.7 y.o.) who underwent primary unilateral ACL reconstruction in this study. The pivot-shift test was performed under anesthesia before ACL reconstruction, and the quantitative evaluation using electromagnetic measurement system (EMS) was conducted to provide the rotational laxity measurements as the tibial

e157

acceleration (m/sec2) in addition to the four levels of clinical grading according to the IKDC (none, glide, clunk, and gross). The presence of the concomitant ALC injury in the ACL injured knees were assessed on the MRI based on the report of Helito et al, forming two groups ALC-injured group (ALC+) and ALC intact-group (ALC-). Chi-square test and independent t-test were used to assess the difference between ALC+ and ALC- groups for clinical grading and quantitative measurements respectively. Statistical significance was defined as a p value of <0.05. Results: There were 42 knees in the ALC+ group and 40 knees in the ALC- group. In clinical grading, there were 21 knees were graded as glide, 18 knees as clunk, and 3 knees as gross in ALC+ group, whereas 21 knees of ACL- group were judged as glide, 16 knees as clunk, and 3 knees as gross respectively. There was no difference in clinical grading between ALC+ and ALC- groups (p ¼ 0.97). The tibial acceleration during the pivot-shift test was also similar in ALC+ group (1.41  1.16 m/sec2) and ALCgroup (1.65  1.29 m/sec2) (p ¼ 0.19). Discussion: The effect of the ALC injury accompanied with the ACL injury on the rotational laxity was not observed in our clinical cases by either clinical grading or quantitative evaluation. Although the ALC injury cannot be accurately identified especially in clinical cases due to its anatomic variation and immature definition, it has recently been suspected as a major factor to aggravate the knee rotational laxity leading to high-grade pivot-shift. In this study, however, the impact of the ALC injury on the rotational laxity was not confirmed. Therefore, we should pay more attention to the other common and identifiable injures such as meniscus and cartilage tear. Conclusion: The concomitant ALC injury determined by MRI did not affect to the rotational laxity in the ACLinjured knees. Category: Knee - ACL Paper #239: Biomechanical Assessment of the Reconstruction of the Anterolateral Ligament During ACL Surgery. The In-Vivo Study RADEK HART, PROF., MD, PHD, FRCS, CZECH REPUBLIC MARTIN KOMZAK, MD, PHD, CZECH REPUBLIC Dept. of Orthopaedics, Znojmo, CZECH REPUBLIC SUMMARY In about 2/3 of cases the addition of the ALL reconstruction during the ACL surgery is important. ABSTRACT DATA Introduction: Patients diagnosed with „isolated“ tear of the anterior cruciate ligament (ACL) often have different degrees of rotational laxity and ACL reconstruction may not restore it completely. Anterolateral structures, particularly the anterolateral ligament (ALL) may be the key to restoring the rotational stability of the knee. Another option how to restore the rotational stability is to perform

e158

2017 ISAKOS ABSTRACTS

the double-bundle (DB) reconstruction. Therefore, the aim of this study was to evaluate the effect of the ALL recontruction during the singl-bundle (SB) ACL surgery and to compare it with the DB reconstruction. Material and Methods: We have conducted a prospective randomised controled study. 40 patients with isolated ACL ruptures were included and divided at random into two groups: SB ACL and ALL reconstruction (Group I; 20 cases) and DB ACL reconstruction (Group II; 20 cases). To evaluate the rotational stability in time “zero“ objectively, all measurements were performed using an image-free computer navigation system. Internal rotation (IR) were done with the rollimeter (force 2,5 Nm) attached to the iron shoe during the surgery. All tests were performed at 30 of flexion. In Group I, IR was tested before the surgery, after the SB ACL reconstruction, and after the additional ALL reconstruction. In Group II, IR was tested before and after the surgery. Demographic data in both groups was similar. The Mann-Whitney U test was used to statistically evaluate the outcomes (p < 0,05). Results: In Group I, mean IR before surgery was 17,6 , after the ACL reconstruction 12,3 (p < 0,05), and after the ALL reconstruction 8,6 (p < 0,05). In 7 cases (35 %) with remaining rotational laxity after the ACL reconstruction less than 12 the stability in IR after the ALL reconstruction did not improve significantly (p > 0,05). In Group II, IR was 18,2 at average before the surgery and 10,4 after the ACL reconstruction (p < 0,05). We found no statistically significant difference between both groups in terms of IR laxity before and after the surgery. Conclusions: Isolated SB reconstruction stabilizes the knee in IR sufficiently only in about 1/3 of patients. In remaining 2/3 of cases the addition of the ALL reconstruction is important. There is no significant difference regarding IR stability between DB reconstruction and SB together with ALL reconstruction. After DB reconstruction remaining IR laxity is higher, but without statistical significance.

Category: Knee - ACL Paper #240: Anatomic Anterolateral Ligament Combined with Single-Bundle Anterior Cruciate Ligament Reconstruction Using the Same Hamstring Graft: Technique Report XUAN HUANG, MD, PHD, CHINA Department of orthopeadics, Changhai hospital, Shanghai, Shanghai, CHINA

SUMMARY Combined anatomic ALL and ACL reconstruction using the same hamstring graft allow the knee to be stabilised in the sagittal plane and the rotatory instability to be controlled in the majority of cases without specific complications.

ABSTRACT DATA Background: Combinations of intra- and extra-articular procedures have been proposed for anterior cruciate ligament (ACL) reconstruction with the aim of achieving an optimal control of translational and rotational knee laxities. Recently, the anterolateral ligament (ALL) has been identified as an important structure involved in rotational laxity after ACL injury. This study aimed to report a novel technique of anatomic ACL and ALL reconstruction with the same hamstring graft. Methods: Sixteen pts, with an isolated ACL injury and grade 3 pivot shift test, underwent the combined procedure. Two different graft settings were selected, 4 strands graft inside the joint and 2 strands for ALL or 2 strands for the whole graft. The outside-in ACL femoral guide was introduced to allow the ALL graft insert at the level of isometric point on the lateral femoral condyle. The distal insertion of the ALL was taken to be roughly halfway between the Gerdy tubercle and the middle of the fibular head. The graft was secured with 3 outside-in bioabsorbable interference screws respectively. Results: All pts were re-examined at an average followup of 76  12months. The average differential anterior drawer test at the last review was 2.5  3.4 mm and 75% pts had a negative pivot shift test at final follow-up. Conclusion: This study demonstrates that a combined anatomic ALL and ACL reconstruction using the same hamstring graft allow the knee to be stabilised in the sagittal plane and the rotatory instability to be controlled in the majority of cases without specific complications. Category: Shoulder - Arthroplasty Paper #241: Does Sex Impact Outcomes Following Shoulder Arthroplasty? RACHEL M. FRANK, MD, UNITED STATES SIMON LEE, MPH, UNITED STATES TIMOTHY LEROUX, UNITED STATES JUSTIN GRIFFIN, MD, UNITED STATES NIKHIL N. VERMA, MD, UNITED STATES BRIAN J. COLE, MD, MBA, UNITED STATES GREGORY P. NICHOLSON, MD, UNITED STATES ANTHONY A. ROMEO, MD, UNITED STATES Rush University Medical Center, Chicago, IL, UNITED STATES

SUMMARY While both males and females undergoing shoulder arthroplasty experience significant clinical improvement, for both TSA and RSA, the magnitude of improvement and final scores in female patients are significantly lower than in male patients. This information can be used to counsel patients undergoing shoulder arthroplasty on their expected outcomes. ABSTRACT DATA Background: The impact of patient sex as an independent factor on clinical outcomes following total shoulder arthroplasty (TSA) and reverse total shoulder