Yong-jian Wang

Comparative study on immediate versus delayed meniscus allograft transplantation: 4- to 6-year follow-up.

Background: Meniscus allograft transplantation (MAT) is generally used for patients who sustain symptoms after meniscectomy, which could be called delayed MAT. Meniscus allograft transplantation for patients immediately after meniscectomy has not been reported. Hypothesis: Compared with the conventional delayed MAT, immediate MAT might provide better clinical results and reduce joint degeneration. Study Design: Cohort study; Level of evidence, 3. Methods: The study was performed with 18 transplanted menisci (6 medial, 12 lateral) from 16 patients. Eight menisci were transplanted immediately after meniscectomy (IM group); 10 menisci, from patients who complained of knee symptoms at a mean time of 35 months (range, 9-92 months) after total meniscectomy, underwent delayed transplantation (DE group). Fourteen patients undergoing meniscectomy during the same period were included as controls (ME group). Degenerative changes in knee joints were evaluated by plain radiographs and magnetic resonance imaging (MRI). Allograft extrusion and relative percentage of extrusion were measured on MRI. Other outcome assessments included preoperative and postoperative International Knee Documentation Committee (IKDC), Tegner, and Lysholm scores; visual analog scale (VAS) for pain; and range of motion and isokinetic muscle strength evaluation. Results: The mean length of follow-up was 50.8 months (range, 44-62 months) for the IM group, 72.0 months (range, 44-94 months) for the DE group, and 54.3 months (range, 45-62 months) for the ME group. A statistically significant difference in favor of the IM and ME groups was found on the VAS (0.4 [IM group] vs 1.1 [ME group] vs 2.5 [DE group]) and muscle strength (P < .05). The mean IKDC score in the IM group was significantly higher than that in the DE group (93 [range, 85-99] vs 74 [range, 38-95], respectively; P < .05). The IM group showed significantly less preoperative to postoperative cartilage degeneration changes on radiographs and MRI when compared with the DE and ME groups (Kellgren-Lawrence score changes: 0.25 [IM group] vs 1.0 [DE group] vs 1.7 [ME group]; Yulish score changes: 0.25 [IM group] vs 1.0 [DE group] vs 1.1 [ME group]; P < .05). Extrusion of the allograft was observed in the body of the menisci in all patients. No significant difference was found in terms of the Lysholm score, Tegner score, joint narrowing, or meniscus extrusion (P > .05). Conclusion: Compared with delayed MAT, immediate MAT led to more satisfactory subjective results, less joint degeneration, and less muscle strength deficits. The short-term results of delayed meniscus transplantation were close to those of meniscectomy.

Second-Look Arthroscopic Evaluation of Chondral Lesions After Isolated Anterior Cruciate Ligament Reconstruction Single- Versus Double-Bundle Reconstruction

Background: Double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) has been reported to yield better joint stability than single-bundle (SB) reconstruction. Few studies have compared the 2 techniques with regard to postoperative articular cartilage changes. Hypothesis: Less cartilage damage should occur in the short term after DB ACLR than after SB ACLR. Study Design: Cohort study; Level of evidence, 2. Methods: The study included 52 patients (27 in the DB group and 25 in the SB group) with no chondral or meniscus injury at primary ACLR, as confirmed under arthroscopy. Four-strand and 6- to 8-strand hamstring autografts, respectively, were used for transtibial SB and 4-tunnel DB reconstruction. Each graft was fixed with an EndoButton bioabsorbable interference screw and a staple. Cartilage status at 6 identified regions was evaluated by second-look arthroscopy and the Outerbridge classification. Other assessments at final follow-up included International Knee Documentation Committee (IKDC) score, Tegner and Lysholm scores, side-to-side difference on KT-2000 arthrometer, and range of motion. Results: The mean time from reconstruction to second-look arthroscopy was 18.2 and 17.3 months for the DB and SB groups, respectively. Both groups had cartilage lesions at the patellofemoral joint (patella, 9 vs 13; trochlea, 5 vs 12) and the medial compartment (1 vs 2). Significantly less severe lesions were found in the DB group than in the SB group (mean grade, 0.33 vs 0.96; P < .05). No significant differences were found between the 2 groups in terms of cartilage status at other regions, IKDC score, Lysholm score, Tegner score, KT-2000 arthrometer anterior laxity, or range of motion. Conclusion: Chondral lesions were found postoperatively in both DB and SB ACLR groups with hamstring autograft. The DB ALCR led to less cartilage damage at the femoral trochlea at short-term follow-up.

Intraoperative anthropometric measurements of tibial morphology: comparisons with the dimensions of current tibial implants

PurposesThis study analyzed morphological differences in the resected proximal tibial surfaces of Chinese males and females undergoing total knee arthroplasty (TKA) and compared the measurements with the dimensions of five currently used tibial implants.MethodsThe mediolateral (ML), middle anteroposterior (AP), medial anteroposterior (MAP), and lateral anteroposterior (LAP) dimensions of the resected tibial surfaces of 976 Chinese TKA knees (177 male, 799 female) were measured. The ML/AP ratio of every knee was calculated. These morphological data were compared with the dimensions of five currently used tibial implants.ResultsThe ML, AP, MAP, and LAP dimensions of the resected proximal tibias showed significant differences according to gender. Compared with currently used tibial implants, the smaller implants showed tibial ML undersizing and the larger implants showed tibial ML overhang. The ML/AP aspect ratio progressively decreased with increasing AP dimension in the resected proximal tibias, which contrasts with the relatively constant or increased (NexGen) aspect ratio in currently used tibial implants. Males showed a higher ML/AP aspect ratio than females for a given AP dimension. This indicates that for an implant with a given AP dimension, the tibial ML dimension tends to be undersized in males and to overhang in females.ConclusionThe results of this study may provide fundamental data for designing suitable tibial implants for use in the Chinese population, especially for design of gender-specific prostheses.Level of evidenceII.

Double-Bundle Anterior Cruciate Ligament Reconstruction Using Bone–Patellar Tendon–Bone Allograft Technique and 2- to 5-Year Follow-up

Background: Nonanatomic transtibial single-bundle anterior cruciate ligament reconstruction (SB-ACLR) with a bone–patellar tendon–bone (BPTB) allograft has been used for a long time and has shown the same satisfactory clinical results as an autograft; however, it has not been reported if a double-bundle ACLR (DB-ACLR) could be performed with a BPTB allograft and achieve even better results. Hypothesis: The DB-ACLR with a BPTB allograft is technically feasible and will be superior to the SB technique in restoring better anterior and rotating stability. Study Design: Cohort study; Level of evidence, 2. Methods: The study was performed with 56 patients, and 52 (25 in the DB group and 27 in the SB group) of them were followed up at 2 to 5 years. With an irradiated deep-frozen BPTB allograft, a standard single-incision arthroscopic technique was used, and the graft was fixed with bioabsorbable interference screws on both the femoral and tibial sides. Outcome assessment at final follow-up included International Knee Documentation Committee (IKDC), Tegner, and Lysholm scores; side-to-side difference by conventional KT-2000 arthrometer; total anteroposterior (AP) laxity by the back-pushing KT-2000 arthrometer; pivot shift (0, +, ++); range of motion (ROM); and isokinetic muscle strength evaluation. Results: Mean follow-up was 47.3 ± 11.5 and 58.2 ± 6.6 months for the DB group and SB group, respectively. A statistically significant difference in favor of the DB group was found with the total AP laxity at 30° (P < .05). The overall incidence of pivot shift in the DB group (4% ++) was significantly lower than that in the SB group (26%: 19% + and 7% ++; P = .029). No significant differences were found between the 2 groups in terms of IKDC score, Lysholm score, Tegner score, conventional KT-2000 arthrometer anterior laxity, ROM, and muscle strength. Conclusion: A DB-ACLR with a BPTB allograft is feasible and achieved more satisfactory results than the transtibial SB technique in terms of total AP stability and rotational stability in spite of no significant differences among other clinical parameters.

Relationship Between Quadriceps Strength and Patellofemoral Joint Chondral Lesions After Anterior Cruciate Ligament Reconstruction

Background: The incidence of the patellofemoral joint chondral lesions after anterior cruciate ligament reconstruction (ACLR) is disturbingly high. Few studies have assessed the factors affecting patellofemoral joint chondral lesions postoperatively. Hypothesis: The recovery of quadriceps strength after ACLR could be associated with patellofemoral joint cartilage damage. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 88 patients who underwent arthroscopic anatomic double-bundle ACLR with hamstring autografts received second-look arthroscopy at the time of metal staple removal at an average of 24.1 months (range, 12-51 months) postoperatively. All patients underwent standardized isokinetic strength testing for bilateral quadriceps and hamstrings 1 to 2 days before second-look arthroscopy. The patients were divided into 2 groups: Patients in group 1 had a ≥20% deficit on the peak torque measures for quadriceps compared with that of the contralateral knee, whereas those in group 2 had a <20% deficit on peak torque. Cartilage status at the patellofemoral joint and tibiofemoral joint were evaluated by second-look arthroscopy and the Outerbridge classification. Other assessments included the International Knee Documentation Committee (IKDC) score, Tegner and Lysholm scores, side-to-side difference on KT-2000 arthrometer, and range of motion. Results: There were 42 patients included in group 1 and 46 patients in group 2. The mean postoperative quadriceps peak torque of the involved knee compared with the contralateral knee was 70% (range, 57%-80%) in group 1 and 95% (range, 81%-116%) in group 2. For all patients, a significant worsening was seen in the patellar and trochlear cartilage (P = .030 and <.001, respectively) but not at the medial or lateral tibiofemoral joint after ACLR. A significant worsening in the status of both patellar and trochlear cartilage was seen after ACLR in group 1 (P = .013 and =.011, respectively) and of trochlear cartilage in group 2 (P = .006). Significantly fewer severe chondral lesions of the patella were found in group 2 than in group 1 (proportion of patients whose cartilage grade worsened: 26% vs 48%, P < .05; difference in cartilage grade: 0.09 vs 0.62, P < .05). There was no significant difference for trochlear chondral worsening between the 2 groups. No significant differences were detected between the 2 groups in terms of hamstring strength; Lysholm, Tegner, and IKDC scores; KT-2000 arthrometer anterior laxity; or range of motion. Conclusion: Greater than 80% recovery of quadriceps strength after ACLR is associated with less severe patellar cartilage damage at short-term follow-up.

Computed tomographic measurement of gender differences in bowing of the sagittal femoral shaft in persons older than 50 years.

Surgeons do not give enough weight to the effects of bowing of the sagittal femoral shaft in total knee arthroplasty (TKA), which can result in damage to the cortex, fractures, or malalignment of the femoral component. To determine gender differences in bowing, we used spiral computed tomography to scan the femurs of 26 men and 47 women older than 50 years who required TKA. Skeletal extraction of the total sagittal femoral shaft from computed tomographic images was done by a matrix laboratory. The extracted curves were evenly divided into 3 sections. Comparison of the curvature on different sections of the same side of the femur showed that the distal third was significantly bowed. In addition, the curvature of the distal third was significantly larger in women than in men. Such morphological characteristics put forward new requirements in how intramedullary guide rods are used in TKA.

The Position of the Posterolateral Bundle Femoral Tunnel During Arthroscopic Double-Bundle Anterior Cruciate Ligament Reconstruction: A Cadaveric Study

PURPOSE The purpose was to find a simple guideline to help establish accurate positioning of the posterolateral bundle (PLB) femoral bone tunnel during double-bundle anterior cruciate ligament reconstruction by measuring the distance between the center of the PLB femoral footprint to the shallow and the deep articular cartilage borders of the lateral wall of the intercondylar notch. METHODS The femoral insertions of the anteromedial bundle and PLB of the anterior cruciate ligament were dissected in 22 male cadaveric knees, aged 25 to 45 years. By use of the intercondylar notch as the landmark, the distances between the center of the PLB femoral footprint and the shallow and the deep articular cartilage borders of the lateral wall of the intercondylar notch were measured with the knees flexed at 90°. The measured data (mean ± standard deviation) were evaluated and compared. RESULTS The center of the PLB was positioned 8.60 ± 1.52 mm and 8.65 ± 1.54 mm from the shallow and the deep cartilage borders of the lateral wall of the intercondylar notch, respectively (P = .95). The distance between the center of the PLB footprint to the low cartilage border of the lateral intercondylar wall was 5.05 ± 0.76 mm. CONCLUSIONS The findings suggest that the position of the center of the PLB femoral footprint is at the middle of the line joining the shallow and the deep borders of the femoral cartilage. CLINICAL RELEVANCE Surgeons can use our results as a guideline and use the PLB footprint remnant as a reference at the same time to locate the femoral PLB tunnel in a simple, easy, and repeatable way.