Hongyue Tao

Difference in Graft Maturity of the Reconstructed Anterior Cruciate Ligament 2 Years Postoperatively: A Comparison Between Autografts and Allografts in Young Men Using Clinical and 3.0-T Magnetic Resonance Imaging Evaluation

Background: Currently, there is an ongoing debate regarding the optimal graft choice between autograft and allograft tendons in reconstruction of the anterior cruciate ligament (ACL). It has been reported that allograft tendons have a slower onset and rate of revascularization compared with autograft tendons. Hypothesis: Allograft tendons might have inferior graft maturity compared with autograft tendons in ACL reconstruction at 2 years postoperatively. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 52 participants with ACL reconstruction were recruited in this study, including 30 using allograft tendons and 22 using autograft tendons. All of them had unilateral ACL reconstruction and were followed up using 3.0-T magnetic resonance imaging (MRI) at least 2 years postoperatively. Clinical examination was performed on the same day when the MRI examination was performed, including subjective functional examinations (International Knee Documentation Committee [IKDC] and Tegner Lysholm Knee Scoring Scale [TLKS]) and physical examinations (anterior drawer test and Lachman test). Four measurements based on MRI were focused on graft orientation (including tibial tunnel position and graft angles), the edematous condition of the graft, intra-articular graft width at different sites, and signal intensity of the ACL graft using the signal/noise quotient (SNQ) from a region of interest analysis. Differences in each measurement were compared between the allograft group and the autograft group. Results: All the participants returned to normal sports activities at the follow-up time point, as all of them acquired full functional strength and stability. There was no significant difference between the autograft and the allograft group with respect to IKDC or TLKS score. The knees in both of the groups were confirmed stable by physical examination before MRI. On MRI measurements, the allograft group displayed no significant difference in graft orientation compared with the autograft group (P > .05). Moreover, there was also no significant difference between allograft group and autograft group in graft width of the distal site (P > .05), middle site (P > .05), and proximal site (P > .05). However, the mean SNQ value of the allograft group was significantly higher than that of the autograft group in the distal site (6.54 ± 6.58 vs 2.98 ± 5.48; P = .0173), the middle site (7.21 ± 6.31 vs 3.56 ± 4.62; P = .0149), and the proximal site (6.61 ± 8.08 vs 2.45 ± 8.12; P = .0018). Conclusion: The allograft group had a significantly higher SNQ value compared with the autograft group in this study, indicating that allograft tendons might have inferior graft maturity than autograft tendons in ACL reconstruction at 2 years postoperatively.

The use of layer by layer self-assembled coatings of hyaluronic acid and cationized gelatin to improve the biocompatibility of poly(ethylene terephthalate) artificial ligaments for reconstruction of the anterior cruciate ligament

In this study layer by layer (LBL) self-assembled coatings of hyaluronic acid (HA) and cationized gelatin (CG) were used to modify polyethylene terephthalate (PET) artificial ligament grafts. Changes in the surface properties were characterized by scanning electron microscopy, attenuated total reflection Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and contact angle and biomechanical measurements. The cell compatibility of this HA-CG coating was investigated in vitro on PET films seeded with human foreskin dermal fibroblasts over 7days. The results of our in vitro studies demonstrated that the HA-CG coating significantly enhanced cell adhesion, facilitated cell growth, and suppressed the expression of inflammation-related genes relative to a pure PET graft. Furthermore, rabbit and porcine anterior cruciate ligament reconstruction models were used to evaluate the effect of this LBL coating in vivo. The animal experiment results proved that this LBL coating significantly inhibited inflammatory cell infiltration and promoted new ligament tissue regeneration among the graft fibers. In addition, the formation of type I collagen in the HA-CG coating group was much higher than in the control group. Based on these results we conclude that PET grafts coated with HA-CG have considerable potential as substitutes for ligament reconstruction.

Quantitative MRI T2 Relaxation Time Evaluation of Knee Cartilage Comparison of Meniscus-Intact and -Injured Knees After Anterior Cruciate Ligament Reconstruction

Background: Associated meniscal injury is well recognized at anterior cruciate ligament (ACL) reconstruction, and it is a known risk factor for osteoarthritis. Purpose: To evaluate and characterize the postoperative appearance of articular cartilage after different meniscal treatment in ACL-reconstructed knees using T2 relaxation time evaluation on MRI. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 62 consecutive patients who under ACL reconstruction were recruited in this study, including 23 patients undergoing partial meniscectomy (MS group), 21 patients undergoing meniscal repair (MR group), and 18 patients with intact menisci (MI group) at time of surgery. Clinical evaluation, including subjective functional scores and physical examination, was performed on the same day as the MRI examination and at follow-up times ranging from 2 to 4.2 years. The MRI multiecho sagittal images were segmented to determine the T2 relaxation time value of each meniscus and articular cartilage plate. Differences in each measurement were compared among groups. Results: No patient had joint-line tenderness or reported pain or clicking on McMurray test or instability. There were also no statistically significant differences in functional scores or medial or lateral meniscus T2 values among the 3 groups (P > .05 for both). There was a significantly higher articular cartilage T2 value in the medial femorotibial articular cartilage for the MS group (P < .01) and the MR group (P < .05) compared with that of the MI group, while there was no significant difference in articular cartilage T2 value between the MS and MR groups (P > .05) in each articular cartilage plate. The medial tibial articular cartilage T2 value had a significant positive correlation with medial meniscus T2 value (r = 0.287; P = .024) Conclusion: This study demonstrates that knees with meniscectomy or meniscal repair had articular cartilage degeneration at 2 to 4 years postoperatively, with higher articular cartilage T2 relaxation time values compared with the knees with an intact meniscus.

Quantitative Magnetic Resonance Imaging Assessment of Cartilage Status: A Comparison Between Young Men With and Without Anterior Cruciate Ligament Reconstruction

PURPOSE To assess the cartilage status of the knee joints using magnetic resonance imaging at least 2 years after anterior cruciate ligament reconstruction (ACLR) in young adult men. METHODS Thirty young male patients with unilateral ACLR and 15 age-matched and body mass index--matched healthy men (controls) participated in this study. All participants underwent quantitative magnetic resonance imaging scans. Three-dimensional dual-echo steady-state sagittal images were segmented using solid model software to calculate the mean cartilage thickness, and multi-echo sagittal images were segmented with Siemens software (Siemens, Erlangen, Germany) to determine the T2 relaxation time of each cartilage plate. RESULTS There was no statistically significant difference in the mean thickness of each cartilage plate between the ACLR and control groups (P = .9616 for lateral femoral cartilage, P = .5962 for lateral tibial cartilage, P = .9328 for patellar cartilage, P = .9712 for trochlear cartilage, P = .4408 for medial femoral cartilage, and P = .1933 for medial tibial cartilage). The ACLR group had significantly higher T2 values than the control group in the lateral femoral cartilage (P < .001), lateral tibia (P = .0011), trochlea (P = .0028), medial femur (P < .001), and medial tibia (P < .001). In addition, the patella showed no difference in T2 values between the 2 groups (P = .2152). The medial compartment cartilage showed a much higher percentage change in cartilage T2 values in the ACLR group. CONCLUSIONS Although no difference in cartilage thickness was detected between the ACLR group and the control group, the mean T2 relaxation time in the ACLR patients was significantly longer than that in control subjects. LEVEL OF EVIDENCE Level III, retrospective comparative study.

Delayed Early Passive Motion Is Harmless to Shoulder Rotator Cuff Healing in a Rabbit Model

Background: Postoperative passive motion is the most widely accepted rehabilitation protocol after rotator cuff repair; however, a rotator cuff retear remains a frequent surgical complication. Clinical outcomes indicate that early passive motion is harmless to rotator cuff healing, but no laboratory evidence supports this proposition. Hypotheses: (1) Immediate postoperative immobilization improves rotator cuff healing in rabbits. (2) Early passive motion after short-term immobilization does not harm rotator cuff healing in rabbits. Study Design: Controlled laboratory study. Methods: An injury to the supraspinatus tendon was created and repaired in 90 New Zealand White rabbits, after which they were randomly separated into 3 groups: (1) nonimmobilization (NI; n = 30), (2) continuous immobilization (IM; n = 30), and (3) immobilization with early passive motion (IP; n = 30). At 3, 6, and 12 weeks postoperatively, 5 rabbits from each group were sacrificed for histological evaluation, biomechanical testing, and magnetic resonance imaging. Results: The histological study demonstrated better postoperative healing in the IM and IP groups, with clusters of chondrocytes accumulated at the tendon-bone junction. Magnetic resonance imaging illustrated that the tendon-bone junction was intact in the IM and IP groups. The magnetic resonance quantification analysis showed that the signal-to-noise quotient (SNQ) of the NI group was not significantly higher than that of the immobilization groups at 3 weeks (P = .232) or 6 weeks (P = .117), but it was significantly different at 12 weeks (NI vs IM, P = .006; NI vs IP, P = .009). At 12 weeks, the failure load was significantly higher in the IM and IP groups than in the NI group (NI vs IM, P = .002; NI vs IP, P = .002), but no difference was found between the IM and IP groups (P = .599). Conclusion: Immediate postoperative immobilization led to better tendon-bone healing than immediate postoperative mobilization, and under immobilization, early passive motion was harmless to tendon-bone healing in this study. Clinical Relevance: The results have an implication in supporting the rehabilitation protocol of early passive motion after rotator cuff repair.

T 2-Mapping evaluation of early cartilage alteration of talus for chronic lateral ankle instability with isolated anterior talofibular ligament tear or combined with calcaneofibular ligament tear: Early Cartilage Alteration of Talus

To quantitatively evaluate the cartilage alteration of talus for chronic lateral ankle instability (LAI) with isolated anterior talofibular ligament (ATFL) tear and combined ATFL and calcaneofibular ligament (CFL) tear using T2‐mapping at 3.0T.

Correlation Analysis of Potential Factors Influencing Graft Maturity After Anterior Cruciate Ligament Reconstruction

Background: Postoperatively, signal changes of the reconstructed anterior cruciate ligament (ACL) graft on magnetic resonance imaging (MRI) images commonly occurs, which may be a cause for concern. The signal intensity changes are usually expressed by signal/noise quotient (SNQ) value, representing graft maturity. To date, little is known about the factors influencing the SNQ value of the reconstructed ACL graft. Purpose: To evaluate ACL graft SNQ value and associated factors after ACL reconstruction. Study Design: Case series; Level of evidence, 4. Methods: Male patients who underwent ACL reconstruction using autograft or allograft tendon from September 2004 to September 2011 were randomly invited to take part in this investigation, including functional scores, physical examination, and MRI scan. The femoral side graft was fixed with Endobutton CL or Rigidfix pins, and the tibial side graft was fixed with a bio-intrafix. SNQ values of each graft were measured on MRI to represent graft maturity. Sagittal ACL angle, ACL–Blumensaat line angle, and medial and lateral posterior tibial slope (PTS) were measured using MRI 3-dimensional dual-echo steady-state images. Potential risk factors, including age, body mass index, postoperative time, Tegner activity scale (TAS), sagittal ACL angle, ACL–Blumensaat line angle, medial PTS, lateral PTS, and primary graft diameter, were tested for their association with the graft SNQ value by multivariate stepwise regression analysis. Results: A total of 104 male subjects (mean follow-up, 30.7 months) were examined, including 62 allograft and 42 autograft reconstructions. There was a significant association between graft SNQ and postoperative time (r = −0.431, P < .001), TAS (r = 0.295, P = .002), and ACL–Blumensaat line angle (r = −0.304, P = .002). Univariate regression analysis showed that TAS (β = 6.15, P < .001) positively correlated, postoperative time (β = −0.26, P < .001) negatively correlated, and ACL–Blumensaat line angle (β = −0.40, P = .038) negatively correlated with graft SNQ. Multivariate stepwise regression analysis showed that TAS, postoperative time, ACL–Blumensaat line angle, and age were significant independent factors associated with graft SNQ. Conclusion: The graft SNQ value had a significant positive correlation with physical activity level and a significant negative correlation with postoperative time in this study. Males with a shorter postoperative time and a higher physical activity level had higher graft signal intensity postoperatively.

Clinical and magnetic resonance imaging assessment of anatomical lateral ankle ligament reconstruction: comparison of tendon allograft and autograft

PurposeTo compare the results of anatomical lateral ankle ligament (LAL) reconstruction with tendon allograft and autograft using clinical scores and ultrashort echo time (UTE) sequence of MRI.MethodsA total of 26 patients with LAL reconstruction were recruited in this study, including 16 using semitendinosus allografts and 10 using semitendinosus autograft. All of them were diagnosed as chronic ankle instability and accepted anatomic reconstruction. The American Orthopedic Foot and Ankle Society (AOFAS) score, Karlsson score, and radiological evaluation using MRI UTE scanning were extracted from each patient. The comparative analysis of the clinical assessments and UTE-T2* values were performed between the patients using autografts and allografts.ResultsFor the allograft group, the mean AOFAS score improved from 69.9 ± 13.3 to 94.8 ± 5.4 (P = 0.000), and the mean Karlsson score improved from 70.3 ± 12.2 to 93.8 ± 5.6 (P = 0.000). For the autograft group, the mean AOFAS score improved from 68.4 ± 10.0 to 94.7 ± 5.0 (P = 0.000), and the mean Karlsson score improved from 64.5 ± 14.4 to 95.0 ± 5.8 (P = 0.000). No significant differences were found between the allograft and autograft neither before (AOFAS P = 0.756, Karlsson P = 0.285) nor after (AOFAS P = 0.957, Karlsson P = 0.574) surgery. While the UTE T2* values in allograft were higher than those of autograft group both in anterior talofibular ligament (8.3 ± 1.0 vs 7.6 ± 1.1 P = 0.027) and intra-tunnel graft (7.8 ± 0.6 vs 7.2 ± 0.8 P = 0.045).ConclusionBoth allograft and autograft reconstructions could get an ideal patient satisfaction and clinical functional outcomes at the follow-up. Higher T2* values were found in allograft group which indicated that autograft had some superiorities in respect of revascularization process, collagen structure, water content, and tendon properties.

T2‐Mapping evaluation of early cartilage alteration of talus for chronic lateral ankle instability with isolated anterior talofibular ligament tear or combined with calcaneofibular ligament tear

To quantitatively evaluate the cartilage alteration of talus for chronic lateral ankle instability (LAI) with isolated anterior talofibular ligament (ATFL) tear and combined ATFL and calcaneofibular ligament (CFL) tear using T2‐mapping at 3.0T.

A Randomized Clinical Trial to Evaluate Attached Hamstring Anterior Cruciate Ligament Graft Maturity With Magnetic Resonance Imaging

Background: The hamstring tendons are commonly harvested for anterior cruciate ligament (ACL) reconstruction with detachment of the tibial insertion. Retaining the insertion may help to preserve vascularity and viability of the graft and bypass the stages of avascular necrosis and revascularization, which might be beneficial to graft maturity. Purpose: To investigate and compare graft maturity by magnetic resonance imaging (MRI) after ACL reconstruction with preservation or detachment of hamstring tendon tibial insertion at up to 2 years. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: Forty-five patients (age range, 18-45 years) undergoing isolated ACL reconstruction with hamstring tendon were enrolled and randomized to 2 groups. The tibial insertion of the hamstring tendon was preserved in the study group (n = 21) and detached in the control group (n = 24). Patients had follow-up at 3, 6, 12, and 24 months, which consisted of the following: (1) clinical examination and (2) MRI evaluation of graft signal intensity based on signal/noise quotient (SNQ) values. Finally, 18 patients in the study group and 19 in the control group received full follow-up evaluation (ie, at all 4 time points). Results: All knees acquired full range of motion at 24 months without significant laxity. At each time point, the KT-1000 arthrometer revealed no significant difference between groups; the clinical scores significantly improved in both groups, although the difference between groups was not significant. In the control group, the SNQ value increased from 3 months, peaked at 6 months, and then decreased (3 months, 21.4 ± 12.7; 6 months, 25.6 ± 12; 12 months, 18.3 ± 7.7; 24 months, 15.3 ± 6.3). However, the insertion-preserved graft in the study group maintained relatively lower and unchanged signal intensity throughout all time points (3 months, 15.0 ± 11.2; 6 months, 14.9 ± 6.3; 12 months, 12.6 ± 7.0; 24 months, 14.6 ± 7.0). Between groups, there was no significant difference at 3 or 24 months (P = .11 and .75, respectively), while the SNQ values were significantly lower in the study group versus the control group at 6 and 12 months (P = .002 and .02, respectively). Conclusion: The insertion-detached hamstring tendon grafts underwent a significantly increasing change in signal intensity during the first 2 years after ACL reconstruction, while the insertion-preserved grafts kept a relatively lower and unchanged signal intensity. The difference was most significant at 6 and 12 months postoperatively.