Jae Gyoon Kim

Anterior Cruciate Ligament Reconstruction Using Remnant Preservation and a Femoral Tensioning Technique: Clinical and Magnetic Resonance Imaging Results

PURPOSE The purpose of this study was to investigate the clinical and magnetic resonance imaging (MRI) results of anterior cruciate ligament (ACL) reconstruction with autogenous hamstring tendon by use of remnant preservation and a femoral tensioning technique. METHODS A total of 53 patients who had ACL reconstruction by use of remnant ACL stump preservation and a femoral tensioning technique were evaluated. Clinical evaluation at a minimum of 2 years after surgery included range of motion, Lachman test, pivot-shift test, KT-2000 arthrometer testing (MEDmetric, San Diego, CA), and clinical scores. Plain radiographs were evaluated for tunnel enlargement. MRI was obtained for evaluation of graft continuity, cyclops-like mass lesion, and positioning of the tibial tunnel. Second-look arthroscopy was performed in 33 patients. RESULTS The clinical scores improved postoperatively. There were statistically significant differences between preoperative and postoperative Lachman tests, pivot-shift tests, and KT-2000 arthrometer measurements. Postoperative MRI was available in 48 patients, and it showed intact graft in 45 patients, 2 partial tears, and 1 complete loss of graft. There were cyclops-like mass lesions in 12 patients, but none showed an extension limitation or pain at extension. The position of the tibial tunnel on the sagittal and coronal view was similar to the position of the normal ACL tibial insertion. The measured tibial tunnel widening on the radiographs at final follow-up was 2.2 ± 1.5 mm. CONCLUSIONS Reconstruction of the ACL by use of preservation and femoral tensioning of the remnant tissue showed good clinical results without increased concerns regarding incorrect tunnel formation. Postoperative MRI showed an increased incidence of cyclops-like mass lesions, but no clinical significance was observed. LEVEL OF EVIDENCE Level IV, case series.

Long-Term Results of Anterior Cruciate Ligament Reconstruction Using Bone–Patellar Tendon–Bone: An Analysis of the Factors Affecting the Development of Osteoarthritis

PURPOSE To evaluate the clinical outcomes and incidence of knee osteoarthritis (OA) and the factors associated with the onset of OA in the 3 compartments of the knee joint separately after anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone autograft. METHODS Clinical and radiologic assessments were obtained from 117 patients (80.1%). At follow-up, knee function was evaluated with the Lysholm score, Hospital for Special Surgery (HSS) score, Tegner score, and International Knee Documentation Committee (IKDC) 2000 forms. We also evaluated stability and donor-site morbidity. On the follow-up radiographs, OA was assessed by IKDC grading. The factors affecting the onset of OA in the 3 compartments of the knee joint were evaluated. RESULTS The mean follow-up period was 10.3 ± 1.0 years. The mean Lysholm and HSS scores significantly increased at final follow-up (P < .001). The mean IKDC subjective score was 90.6, and 93.9% of patients had grade A or grade B knees on the objective evaluation. The mean side-to-side difference measured by KT-2000 arthrometer (MEDmetric, San Diego, CA) was 1.6 ± 1.7 mm, with 82.0% of patients showing a difference of less than 3 mm. Discomfort from knee walking on hard ground and skin numbness were reported by 38.4% and 37.6% of patients, respectively. OA developed in the medial, lateral, and patellofemoral compartments in 30.7%, 9.3%, and 7.6% of patients, respectively. The onset of OA was associated with partial meniscectomy (odds ratio [OR], 20.73; P = .005) or sagittal tibial tunnel position (OR, 1.18; P = .02) in the medial compartment and body mass index (BMI) (OR, 1.56; P = .02) in the lateral compartment. CONCLUSIONS ACL reconstruction with bone-patellar tendon-bone autograft showed satisfactory clinical results after a mean of 10.3 years. However, pain when walking on hard ground (38.4%) and numbness of the skin (37.6%) were reported. Moreover, the onset of OA appeared in over 40% of the patients. The onset of OA in the medial compartment was correlated with partial meniscectomy and sagittal tibial tunnel position, and the onset of OA in the lateral compartment was correlated with higher BMI. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Femoral Graft Bending Angle and Femoral Tunnel Geometry of Transportal and Outside-In Techniques in Anterior Cruciate Ligament Reconstruction: An In Vivo 3-Dimensional Computed Tomography Analysis

PURPOSE To compare femoral graft bending angles and femoral tunnel geometries between the transportal (TP) and outside-in (OI) techniques after anatomic double-bundle (DB) anterior cruciate ligament (ACL) reconstruction. METHODS Thirty-nine patients underwent DB ACL reconstruction with the TP and OI techniques. They were randomized on the day of surgery to either the TP group (group I, 21 cases) or the OI group (group II, 18 cases). Femoral graft bending angle, femoral tunnel geometry, posterior wall breakage, and tunnel communication were assessed by computed tomography imaging with OsiriX imaging software (Pixmeo, Geneva, Switzerland). RESULTS The mean anteromedial (AM) and posterolateral (PL) femoral graft bending angles of group II (97.3° ± 8.3° and 97.4° ± 8.6°, respectively) were significantly more acute than those of group I (108.2° ± 8.4° and 109.9° ± 8.8°, respectively) (P < .001). The mean AM femoral tunnel length of group II (34.3 ± 3.9 mm) was significantly longer than that of group I (31.9 ± 2.7 mm) (P = .02). However, the mean PL femoral tunnel lengths did not differ between groups. In 7 cases-4 cases (19.0%) in group I and 3 cases (16.6%) in group II-the femoral tunnel communication was found around the intra-articular aperture. Posterior wall breakage was observed in 5 cases (23.8%), which were all in AM femoral tunnels of group I. CONCLUSIONS The OI technique resulted in more acute femoral graft bending angles (difference of 10.9° and 12.5° for AM and PL, respectively) and longer mean AM femoral tunnel lengths (difference of 2.4 mm) than the TP technique after anatomic DB ACL reconstruction, even though these small differences might be unlikely to be of clinical significance. Femoral tunnel communication was found in both groups, and posterior wall breakage was observed in AM femoral tunnels with the TP technique. LEVEL OF EVIDENCE Level I, prospective randomized trial.

Computed Tomography Analysis of the Femoral Tunnel Position and Aperture Shape of Transportal and Outside-In ACL Reconstruction Do Different Anatomic Reconstruction Techniques Create Similar Femoral Tunnels?

Background: The desire to perform independent femoral drilling in anterior cruciate ligament (ACL) reconstruction has prompted interest in both the transportal (TP) and outside-in (OI) techniques. However, there have been no in vivo studies on the differences in femoral aperture shape between the 2 techniques. Purpose: To evaluate the femoral tunnel aperture shape and femoral tunnel position between ACL reconstruction using the TP and OI techniques. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A total of 80 patients were randomized to undergo double-bundle ACL reconstruction using either the TP (n = 40) or OI (n = 40) technique. The femoral tunnel aperture shape (height/width ratio), aperture axis angle (angle between the aperture axis and femoral shaft axis), and femoral tunnel position were assessed by computed tomography. Results: The mean height/width ratio of the anteromedial (AM) femoral tunnels in the TP group (1.35 ± 0.16) was significantly more ellipsoidal than that in the OI group (1.22 ± 0.16) (P = .008). There was no difference between the 2 groups in the posterolateral (PL) tunnels (TP, 1.32 ± 0.23; OI, 1.35 ± 0.29; P = .99). The mean aperture axis angle of the PL femoral tunnels in the OI group was significantly more perpendicular to the femoral shaft axis and had a more variable range than that in the TP group (P = .007). The mean PL femoral tunnel position in the OI group was significantly shallower and a little higher than that in the TP group (P = .006). Conclusion: The TP technique revealed a more ellipsoidal AM femoral tunnel aperture than the OI technique. The mean PL femoral tunnel position in the OI group was significantly shallower than that in the TP group, with a more variable and more perpendicular aperture axis angle to the femoral shaft axis. Clinical Relevance: The TP technique might be more advantageous than the OI technique in terms of graft coverage, with a more ellipsoidal AM femoral tunnel and more horizontal and consistent PL aperture axis angle. In addition, it may be useful to consider the shallower PL femoral tunnel positions created with the OI technique.

Is Femoral Tunnel Length Correlated With the Intercondylar Notch and Femoral Condyle Geometry After Double-Bundle Anterior Cruciate Ligament Reconstruction Using the Transportal Technique? An In Vivo Computed Tomography Analysis

PURPOSE To analyze femoral tunnel geometry using computed tomography (CT) imaging and evaluate the anatomic factors affecting femoral tunnel length after anterior cruciate ligament (ACL) reconstruction by the transportal technique. METHODS Twenty-nine patients underwent an anatomic double-bundle ACL reconstruction with a femoral tunnel drill by the transportal technique. CT imaging with OsiriX software (version 3.8; Pixmeo, Geneva, Switzerland) was used to measure femoral tunnel length (anteromedial [AM], posterolateral [PL], and central), femoral tunnel divergent angle, and femoral condyle size and intercondylar notch size parameters. Correlations between femoral tunnel length and femoral condyle size and intercondylar notch size parameters were analyzed. RESULTS The mean AM, PL, and central femoral tunnel lengths were 33.3 ± 3.9 mm, 33.6 ± 3.6 mm, and 34.3 ± 3.2 mm, respectively. A femoral tunnel length of less than 30 mm developed in 7 cases (24.1%) in the AM aspect and 4 cases (13.8%) in the PL aspect. The mean femoral tunnel divergent angle was 14.4° ± 4.1°. A positive correlation was found between AM, not PL or central, femoral tunnel length and medial femoral condyle anteroposterior (AP) distance (P = .01, r = 0.46), lateral femoral condyle AP distance (P = .01, r = 0.43), medial-to-lateral epicondylar distance (P = .03, r = 0.39), middle notch width (P = .009, r = 0.47), notch height (P = .001, r = 0.57), and notch area (P < .001, r = 0.58). CONCLUSIONS After double-bundle ACL reconstruction with the transportal technique through the accessory anteromedial portal, the AM and PL femoral tunnels showed mean tunnel length greater than 30 mm and a divergent angle. However, a femoral tunnel length of less than 30 mm developed in some cases. AM femoral tunnel length was correlated with femoral condyle size (medial femoral condyle AP distance, lateral femoral condyle AP distance, and medial-to-lateral epicondylar distance) and intercondylar notch size (notch width, notch height, and notch area). LEVEL OF EVIDENCE Level IV, therapeutic case series.

Comparison of femoral tunnel geometry, using in vivo 3-dimensional computed tomography, during transportal and outside-in single-bundle anterior cruciate ligament reconstruction techniques

PURPOSE To compare the transportal (TP) and outside-in (OI) techniques regarding femoral tunnel position and geometry after anatomic single-bundle (SB) anterior cruciate ligament (ACL) reconstruction. METHODS This study included 51 patients who underwent anatomic SB ACL reconstruction with the TP (n = 21) or OI (n = 30) technique. All patients underwent 3-dimensional computed tomography 3 days after the operation. The femoral tunnel position (quadrant method), femoral graft bending angle, femoral tunnel length, and posterior wall breakage were assessed by immediate postoperative 3-dimensional computed tomography with OsiriX imaging software. RESULTS The OI technique had a shallower femoral tunnel position (arthroscopic position) than did the TP technique (P = .005). The mean femoral graft bending angle was significantly more acute with the OI technique (101.3° ± 8.2°) than with the TP technique (107.9° ± 10.0°) (P = .02). The mean femoral tunnel length was significantly greater with the OI technique (33.0 ± 3.5 mm) than with the TP technique (29.6 ± 3.9 mm) (P = .003). Posterior wall breakage occurred in 7 cases (33.3%) with the TP technique and 1 case (3.3%) with the OI technique (P = .02). CONCLUSIONS The mean femoral tunnel position was significantly shallower (arthroscopic position) with the OI technique than with the TP technique. The OI technique resulted in a more acute femoral graft bending angle, longer femoral tunnel length, and lower incidence of posterior wall breakage than did the TP technique. These results might be helpful for anatomic SB ACL reconstruction using TP and OI techniques. LEVEL OF EVIDENCE Level III, retrospective comparative study.

Gender differences of the morphology of the distal femur and proximal tibia in a Korean population

PURPOSE We conducted this study to determine whether the sizes of distal femurs and proximal tibiae in Korean men and women are different, and to assess suitability of the sizes of prostheses currently used in Korea. MATERIALS AND METHODS We performed morphological analysis of proximal tibia and distal femur on 115 patients (56 male, 59 female) using MRI to investigate a gender difference. Tibial mediolateral dimension (tMAP), tibial medial anteroposterior dimension (tMAP), tibial lateral anteroposterior dimension (tLAP) femoral mediolateral dimension (fML), femoral medial anteroposterior dimension (fMAP), and femoral lateral anteroposterior dimension (fLAP) were measured. The ratio of tMAP and tLAP to tML (plateau aspect ratio, tAP/tML×100%), and that of fMAP and fLAP to fML (condylar aspect ratio, fAP/fML×100%) were calculated. The measurements were compared with the similar dimensions of four total knee implants currently used. RESULTS The tML and tAP lengths showed a significant gender difference (P<0.05). The plateau aspect ratio (tMAP/tML) revealed a significant difference between male (0.74±0.05) and female (0.68±0.04, P<0.05). For morphotype of distal femur, males were found to have significantly large values (P<0.05) in the parameters, except for fLAP. With regards to the ratio of the ML width to the AP length, the women showed a narrower ML width than the men. Both genders were distributed within the range of the dimensions of the prostheses currently used prostheses. CONCLUSIONS Korean population revealed that women have smaller dimensions than male counterparts. In both genders, a relatively small size of prostheses matches distal femur and proximal tibia better among the implants currently used in Korea.

Are Navigation Systems Accurate Enough to Predict the Correction Angle During High Tibial Osteotomy? Comparison of Navigation Systems With 3-Dimensional Computed Tomography and Standing Radiographs

Background: Unpredicted overcorrection of the mechanical axis can occur during navigation-assisted high tibial osteotomy (HTO). It is not clear whether the erroneous overcorrection stems from the navigation system itself or from other causes. Purpose: To evaluate the accuracy of the navigation system in HTO by comparing the change in the femorotibial angle provided by the navigation system with the bony correction angle of the proximal tibia on 3-dimensional computed tomography (3D CT) and with the change in mechanical femorotibial alignment on standing whole-leg radiographs. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A total of 16 knees underwent navigation-assisted HTO, and their alignment data were obtained before and after correction. For comparison, preoperative and follow-up standing whole-leg anteroposterior radiographs, lateral knee radiographs, and preoperative and postoperative 3D CT scans were taken. The medial proximal tibial angle (MPTA), posterior tibial slope, and mechanical femorotibial angle (mFTA) were measured in these images, and the 3 coronal and 3 sagittal correction angles were compared with each other. Results: In the coronal plane, the mean correction angle of the navigation system was 9.3° ± 2.0° valgus (range, 6°-13°), and the mean MPTA on 3D CT increased 9.7° ± 2.0° (range, 6.7°-13.8°) after correction. The mean correction angle of the mFTA on standing radiographs was 11.9° ± 3.2° valgus (range, 6.9°-16.5°). There was no statistical significance between the navigation system and 3D CT (P = .187), but there was a statistically significant difference between the navigation system and standing radiographs (P = .001). The results of the correction angle in the sagittal plane were similar to those in the coronal plane. Conclusion: The correction of the femorotibial angle by the navigation system was not different from the bony correction angle on 3D CT. There was a discrepancy between the correction angle of the navigation system and that of the standing radiograph. Clinical Significance: Surgeons must be cautious about the tension of soft tissue, even when using the navigation system during HTO.

A Comparative Study of Screw and Helical Proximal Femoral Nails for the Treatment of Intertrochanteric Fractures

The goal of this study was to compare treatment outcomes of screw proximal femoral nails and helical proximal femoral nails and to investigate the effectiveness of helical proximal femoral nails for the treatment of intertrochanteric fractures. Forty patients with intertrochanteric fractures were treated at our institution between January 2005 and January 2007, with a minimum follow-up of 1.5 years. Seventeen patients were treated with screw proximal femoral nails (mean patient age, 67 years; age range, 45-89 years; men:women ratio, 3:14), and 23 were treated with helical proximal femoral nails (mean patient age, 74 years; age range, 64-91 years; men:women ratio, 6:17). We evaluated mean operation time, amount of bleeding, time to ambulation, average union period, changes in neck shaft angle, and complications, and performed radiographic reviews, telephone interviews, and direct contact interviews at an outpatient clinic. We evaluated postoperative function and mobility using social function scores and mobility scores.Helical proximal femoral nails produced better results in terms of social function scores, mobility scores, and complication rates with statistical significance. No significant differences were found between the 2 nails in terms of mean operation time, amount of bleeding, average union period, time to ambulation, or neck shaft angle changes. Screw proximal femoral nails and helical proximal femoral nails are suitable implants for intertrochanteric fractures, but helical proximal femoral nails are better in terms of functional aspects and complication rates.

Incarcerated patellar tendon in Hoffa fracture: an unusual cause of irreducible knee dislocation.

Irreducible knee dislocation due to incarcerated soft tissue structures in associated fractures is extremely uncommon. We report a case of irreducible, closed dislocation of the knee secondary to incarcerated patellar tendon in a Hoffa fracture (unicondylar fracture of femur in the coronal plane) with associated communited fracture of patella and disruption of both cruciates. We treated this case initially with open reduction and internal fixation of fracture and repair of the patellar tendon. During the total followup period of eighteen months, the patient had restricted joint range of motion with no joint instability despite aggressive physiotherapy and further surgical intervention. The prognosis of such complex knee injuries with combination of ligamentous injuries and associated fractures is much worse when compared to either injuries alone.