A Comparative Study of Clinical Outcomes and Second-Look Arthroscopic Findings between Remnant-Preserving Tibialis Tendon Allograft and Hamstring Tendon Autograft in Anterior Cruciate Ligament Reconstruction: Matched-Pair Design.

BACKGROUND: This study aimed to compare stability, functional outcome, and second-look arthroscopic findings after anterior cruciate ligament reconstruction between remnant-preserving tibialis tendon allograft and remnant-sacrificing hamstring tendon autograft. METHODS: We matched two groups (remnant-preserving tibialis tendon allograft group and hamstring tendon autograft group) in terms of demographic characteristics, associated injury, and knee characteristics. Each group consisted of 25 patients. RESULTS: Operation time was longer in the remnant-preserving tibialis tendon allograft group, but there was no significant intergroup difference in stability, clinical outcome, and second-look arthroscopic findings. CONCLUSIONS: When an autograft is not feasible in anterior cruciate ligament reconstruction, the remnant-preserving technique can produce comparable results in terms of restoration of function, stability of the knee, and degree of synovium coverage at second-look arthroscopy compared to remnant-sacrificing hamstring autograft.

Immunohistochemical and immunocytochemical study of mechanoreceptors in anterior cruciate ligament reconstruction with the remnant-preserving technique using Achilles tendon allografts.

BACKGROUND: Attempts have been made to validate the significance of remnant preservation with anterior cruciate ligament (ACL) reconstruction using immunohistochemical and immunocytochemical techniques. The purpose of this study was to examine the expression of mechanoreceptors in the remnant tissue of ACL reconstruction performed with the remnant-preserving technique. METHODS: Tissue samples were obtained from 10 patients who underwent ACL reconstruction with the remnant-preserving technique. The specimens were obtained from remnant ACL tissue and Achilles allografts superficially and at the tibial attachment. The control group consisted of three normal ACLs procured from young males who underwent partial meniscectomy. Tissues and cells from the ACL remnants and Achilles allografts were characterized using hematoxylin and eosin (H&E) staining and immunohistochemical, immunocytochemical, and immunoblotting assays. In particular, the sensitivity of neural cell validation was improved using nerve growth factor (NGF) to stimulate the expression of neural cells. RESULTS: The results are summarized as follows. (1) In H&E staining and immunohistochemical assays, no neural cells were detected in remnant or allograft tissue. (2) In the immunocytochemical study, neural cells were detected in remnant tissue. (3) The increased proliferation of remnant ACL cells with NGF treatment suggested their identity as neural cells. (4) NGF treatment also stimulated protein and RNA expression of Nestin (a specific marker for neural cells) in remnant ACL cells. CONCLUSIONS: The improved immunocytochemical methodology proved useful. Although mechanoreceptors were detected relatively less frequently than expected, the authors consider that this finding does not negate the necessity of remnant-preserving ACL reconstruction.

A Comparative Study of Clinical Outcomes and Second-Look Arthroscopic Findings between Remnant-Preserving Tibialis Tendon Allograft and Hamstring Tendon Autograft in Anterior Cruciate Ligament Reconstruction: Matched-Pair Design

BACKGROUND: This study aimed to compare stability, functional outcome, and second-look arthroscopic findings after anterior cruciate ligament reconstruction between remnant-preserving tibialis tendon allograft and remnant-sacrificing hamstring tendon autograft. METHODS: We matched two groups (remnant-preserving tibialis tendon allograft group and hamstring tendon autograft group) in terms of demographic characteristics, associated injury, and knee characteristics. Each group consisted of 25 patients. RESULTS: Operation time was longer in the remnant-preserving tibialis tendon allograft group, but there was no significant intergroup difference in stability, clinical outcome, and second-look arthroscopic findings. CONCLUSIONS: When an autograft is not feasible in anterior cruciate ligament reconstruction, the remnant-preserving technique can produce comparable results in terms of restoration of function, stability of the knee, and degree of synovium coverage at second-look arthroscopy compared to remnant-sacrificing hamstring autograft.

Does the tibial remnant of the anterior cruciate ligament promote ligamentization?

BACKGROUND: The purpose of this study was to clarify the difference in ligamentization between the remnant-preserving (RP) and remnant-sacrificing (RS) techniques in anterior cruciate ligament (ACL) reconstruction using magnetic resonance imaging (MRI). METHODS: A retrospective comparative study was carried out on 98 patients undergoing ACL reconstruction using either an RP (n=56) or RS (n=42) technique. MRI was performed at one of four time points postoperatively, and the signal intensity of the ACL graft was analyzed using the signal to noise quotient (SNQ) ratio and inter-bundle high signal intensity, along with an analysis of the survival rate of remnant tissue. RESULTS: The mean SNQ ratio of grafted tendons in the RP group was significantly higher than that seen in the RS group in the proximal and middle regions two to four months after surgery (P<0.05) and was significantly lower than that seen in the RS group in all regions at 12 -18months (P<0.05). The inter-bundle high signal intensity was observed more frequently in the RP group (73.7%) at two to four months. Tibial remnants were observed on postoperative MRI regardless of when MRI was conducted. CONCLUSION: The ACL graft of the RP group showed higher signal intensity in the early stage and lower signal intensity in the late stage compared to that of the RS group. The ligamentization of grafts in the RP group proceeded more quickly. Preserving the remnant in ACL reconstruction appears to have a positive effect on ligamentization.

Comparison of Magnetic Resonance Imaging of Remnant Preserving versus Remnant Sacrificing Technique after Anterior Cruciate Ligament Reconstruction; Clinical Results and Second-Look Arthroscopic Findings: Pilot Study / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to clarify the difference between the remnant-preserving and remnant-sacrificing techniques in anterior cruciate ligament (ACL) reconstruction using stress test, functional score, 2nd look arthroscopy and magnetic resonance imaging (MRI). MATERIALS AND METHODS: Among 66 patients having anatomical ACL reconstruction with the fourstrand hamstring autograft using outside-in technique (FlipCutter(R)) for the femoral tunnel from April 2012 to April 2014, 23 patients who underwent 2nd look arthroscopy and MRI were included. The remnant-preserving group included 12 patients and the remnant-sacrificing group included 11 patients. The two groups were compared and analyzed with regard to stability (Stress test using GNRB(R), pivot shift test), functional assessment (International Knee Documentation Committee [IKDC] scale, Lysholm score, one leg hoop test), and the result of second-look arthroscopy and signal to noise quotient (SNQ) ratio of the graft in MRI. RESULTS: The two groups did not differ significantly in the stability test, IKDC scale, and Lysholm test. The remnant-preserving group showed significant improvement in one leg hoop test compared with the remnant-sacrificing group (p0.05). CONCLUSION: More than 12 months after surgery, the graft of the remnant-preserving group showed lower signal intensity compared to that of the remnant-sacrificing group by MRI evaluation. The remnant preserving technique has biological difference compared with the remnant sacrificing technique in human study.

Comparison of second-look arthroscopic findings and clinical results according to the amount of preserved remnant in anterior cruciate ligament reconstruction.

BACKGROUND: Although ACL reconstruction is prevalent, the most effective method for ACL reconstruction still remains controversial. The purpose of this study was to evaluate the effect of the preserved remnant in ACL reconstruction on graft morphology at second-look arthroscopy and clinical outcomes. METHODS: 66 consecutive patients who underwent a second-look arthroscopy after a remnant-preserving ACL reconstruction were enrolled. The patients were divided into two groups according to whether the remnant ACL fibers could be preserved by over 50% (Group I) or not (Group II). The Lysholm score, IKDC subjective score, Tegner activity score, pivot-shift test, and KT-2000 arthrometric findings were evaluated preoperatively and just prior to the second-look arthroscopy to assess clinical outcomes. At second-look arthroscopy, graft morphology was evaluated using hypertrophy rate and synovialization. RESULTS: At second-look arthroscopy, the hypertrophy rate of Group I (42.1%) was higher than Group II (25.1%), which was statistically significant (p=0.002). In graft synovialization, there was a statistically significant difference between the two groups (p<0.001). The IKDC subjective score improved from 42.9, 43.1 to 77.8, 75.0 for Group I and Group II, respectively (p=0.025). For the Lysholm score, Group I and Group II improved from 55.4 and 55.7 to 87.8 and 84.9 (p=0.031). There was also a significant difference between the pivot shift tests between the groups (p=0.039). Other clinical tests showed no statistically significant differences. CONCLUSION: Preserving the remnant ACL tissue during ACL reconstruction could have a positive effect on graft hypertrophy, synovialization and clinical outcomes. LEVEL OF EVIDENCE: III, retrospective comparative study.

Comparison of Clinical Results and Second-Look Arthroscopic Findings of Remnant Preserving versus Non-Remnant Preserving Technique after Anterior Cruciate Ligament Reconstruction Using Achilles Allograft / 대한정형외과학회잡지

PURPOSE: This study was conducted for evaluation of clinical uses of anterior cruciate ligament (ACL) reconstruction with an Achilles allograft using the remnant technique by comparison and analysis stability, functional assessment and results of second-look arthroscopy between the remnant technique and the non-remnanat technique. MATERIALS AND METHODS: A total of 48 patients who underwent ACL reconstruction using an Achilles allograft were selected and divided into two groups depending on the presence of remnant. The preserving group included 26 patients and non-preserving group included 22 patients. The two groups were compared and analyzed with regarding to stability (Stress view Lachman test, pivot shift test), functional assessment (International Knee Documentation Committee, Lysholm score, Tegner score, single hoop test, shuttle turn, carioca test), and the result of second-look arthroscopy (study design: prosepective cohort study). RESULTS: In the final result, the remnant group showed significant improvement in the Tegner and carioca tests compared with the non-remnant group (p<0.05). In second-look arthroscopy, the remnant group showed better coverage of synovium (p<0.05). CONCLUSION: ACL reconstruction with an Achilles allograft using the remnant technique showed better results in functional assessment and finding in second-look arthroscopy compared with the non-remnant technique group.

Proprioceptive and Knee Joint Kinematics for Comparison of Remnant Preserved versus Non-remnant Anterior Cruciate Ligament Reconstruction Using Achilles Allograft / 대한스포츠의학회지

The purpose of remnant preserving technique in anterior cruciate ligament (ACL) reconstruction is to preserve mechanoreceptor and accelerate revascularization. In this study, we compared a group who underwent remnant preserving technique using Achilles tendon allograft with the other group of conventional ACL reconstruction in terms of proprioception, kinematic analysis, knee strength test and dynamic postural stability. Twenty-four patients were followed up for longer than 12 months after ACL reconstruction. They were separated into two groups; remnant preserving group (n=12) and non-remnant group (n=12). Proprioception test was conducted through joint position sense (JPS) and threshold to detection of passive motion. The remnant preserving group showed significantly less difference from the normal side than the non-remnant group. In kinematic analysis, there was statistically significant difference in peak flexion angle during the swing phase. However the 60degrees JPS, knee strength test, performance capacity test and dynamic postural stability did not showed the significant difference. Remnant preserving technique of ACL reconstruction was meaningful in preserving proprioception and the result showed akin to the unaffected gait.