Chong-Hyuk Choi

Magnetic Resonance Imaging Evidence of Meniscal Extrusion in Medial Meniscus Posterior Root Tear

PURPOSE The purpose of this study was to evaluate the relation between meniscal extrusion on magnetic resonance imaging (MRI) and tearing of the posterior root of the medial meniscus, as well as to understand the relation between meniscal extrusion and chondral lesions. METHODS From January 2007 to December 2008, 387 consecutive cases of medial meniscal tears were treated arthroscopically. Of these cases, 248 (64.1%) with MRI were reviewed. Arthroscopic findings were reviewed for the type of tear and medial compartment cartilage lesion. Root tear was defined as a radial tear in the posterior horn of the medial meniscus near the tibial spine (i.e., within 5 mm of the root attachment). An MRI scan of the knee was used to evaluate the presence and extent of meniscal extrusion. Meniscal extrusion of 3 mm or greater was considered pathologic. Arthroscopic findings were compared with respect to the extent of meniscal extrusion. RESULTS There were 98 male patients and 150 female patients. The mean age was 53.5 years (range, 15 to 81 years). The results showed 127 cases (51.2%) in which the medial meniscus had meniscal extrusion of 3 mm or greater. Posterior root tears were found in 66 (26.6%) of the 248 knees. The mean meniscal extrusion in patients with root tear was 3.8 ± 1.4 mm, whereas the mean extrusion of those who had no root tear was 2.7 ± 1.3 mm. We found an association between pathologic meniscal extrusion and root tear (P < .001). Meniscal extrusion showed a low positive predictive value (39%) and specificity (58%) with regard to the meniscal root tear. Meniscal extrusion was also significantly correlated with severity of chondral lesions (P < .001). CONCLUSIONS Considerable extrusion (≥3 mm) can be associated with tearing of the medial meniscus root and chondral lesion of the medial femoral condyle. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Bilateral complete discoid medial menisci combined with anomalous insertion and cyst formation

A female student had a complete discoid medial meniscus of right knee combined with a meniscal cyst and anomalous insertion to the anterior cruciate ligament. This was confirmed by magnetic resonance imaging (MRI) and the arthroscopic procedure. Also shown by the MRI, the left knee had the discoid medial meniscus, but it was asymptomatic.

Medial Meniscal Tears in Anterior Cruciate Ligament-Deficient Knees: Effects of Posterior Tibial Slope on Medial Meniscal Tear

Purpose To evaluate the incidence of meniscal tears in patients with chronic anterior cruciate ligament (ACL)-deficient knees, and to determine the influence of posterior tibial slope (PTS) on medial meniscal tears in ACL-deficient knees. Materials and Methods We reviewed 174 patients (174 knees) with a mean age of 30.7 years who underwent ACL reconstruction for chronic ACL tears. We divided the patients into two groups: low group (135 knees with a PTS<13°) and high group (39 knees with a PTS≥13°). Results The incidence of medial meniscus tears was 44% (77/174), and that of lateral meniscus tears was 35% (61/174). The mean PTS in patients with medial meniscal tears was 11.4°±3.0°, whereas that in patients without medial meniscal tears was 9.8°±2.4°. The incidence of meniscal tears was 57.8% (78/135) in the low group and 89.7% (35/39) in the high group (p<0.001). Conclusions Our data demonstrate that PTS≥13° is a risk factor for secondary medial meniscal tears in ACL-deficient knees. So, we suggest that PTS is one of the considerations for determining early ACL reconstruction to prevent secondary meniscal tears.

Graft Selection in Anterior Cruciate Ligament Reconstruction for Smoking Patients

Background: There has been no previous study regarding graft selection in anterior cruciate ligament (ACL) reconstruction for smoking patients. Purpose: To compare the clinical outcomes of ACL reconstruction between smokers and nonsmokers and to find an optimal graft in ACL reconstruction with regard to clinical outcomes for smoking patients. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 487 patients who underwent unilateral ACL reconstruction were retrospectively reviewed. Included patients were divided into 2 groups according to their history of smoking. Group 1 was composed of patients who had never smoked (n = 322), and group 2 consisted of patients who had reported smoking before ACL reconstruction and during rehabilitation (n = 165). Additionally, each group was divided into 4 subgroups according to the selected graft type (bone–patellar tendon–bone autograft, hamstring [semitendinosus-gracilis] tendon autograft, quadriceps tendon–bone autograft, or Achilles tendon–bone allograft). Patients were assessed for knee instability with the Lachman and pivot-shift tests as well as anterior translation measured by the KT-2000 arthrometer. Functional outcomes were evaluated with the Lysholm knee score, International Knee Documentation Committee (IKDC) subjective score, and IKDC objective grade. Results: The minimum follow-up period was 24 months. At the final follow-up evaluation, there were significant mean between-group differences regarding the side-to-side difference in anterior translation (group 1, 2.15 ± 1.11 mm; group 2, 2.88 ± 1.38 mm; P < .001), Lysholm knee score (group 1, 90.25 ± 6.18; group 2, 84.79 ± 6.67; P < .001), IKDC subjective score (group 1, 89.16 ± 5.01; group 2, 83.60 ± 7.48; P < .001), and IKDC objective grade (group 1, grade A = 151, B = 130, C = 36, D = 5 patients; group 2, grade A = 48, B = 71, C = 37, D = 9 patients; P < .001). With regard to differences in outcomes between the selected grafts within each group, the Achilles tendon–bone allograft showed the worst outcomes, with statistically significant mean differences for smoking patients in the side-to-side difference in anterior translation (3.59 ± 1.26 mm), Lysholm knee score (81.05 ± 2.82), and IKDC subjective score (79.73 ± 4.29). Conclusion: Unsatisfactory outcomes with regard to stability and functional scores were shown in the smoking group compared with the nonsmoking group. In smokers, the patients receiving an Achilles tendon–bone allograft had poorer outcomes than those with autografts. The bone–patellar tendon–bone autograft is recommendable for ACL reconstruction in a smoking patient.

Correction of lumbosacral hyperlordosis in achondroplasia.

Anterior bulging of the abdomen and posterior protrusion of the buttocks are externally visible deformities reflecting lumbosacral hyperlordosis. Imbalance in pelvic femoral muscles may account for this posture. Despite the clinical significance of hyperlordosis, its surgical treatment has not been well-described. In the current preliminary study, the authors compare two techniques used at the authors’ institution for lower limb lengthening, one of which affects the correction of lumbosacral hyperlordosis. Ten patients had bilateral lower extremity lengthening procedures. Seven patients had bilateral tibial lengthening and three patients had combined femoral and tibial lengthening. Ring external fixators were used. Correction of hyperlordosis was assessed by comparing four radiographs with measurements in the sagittal plane obtained preoperatively with those at the latest followup. In the femoral lengthening group, the average preoperative lumbar lordosis angle was 18°, the lumbosacral joint angle was 12°, the sacral inclination angle was 58.3°, and the sacrohorizontal angle was 31°. The mean changes at the latest followup were: lumbar lordosis angle (+1°), lumbosacral joint angle (+0.3°), sacral inclination angle (−19°), and sacrohorizontal angle (−15°). In the tibia lengthening group, all parameters were relatively unaltered at the last followup compared with their preoperative levels. Tibial lengthening had no effect on lumbosacral hyperlordosis. However, femoral lengthening resulted in an improved apparent lumbosacral hyperlordosis, although the lumbar lordosis angle was not changed significantly. The change in sacrum tilting provides a likely explanation for the improvement in cosmetic hyperlordosis observed in patients who have had femoral lengthening.

Intertunnel Relationships in Combined Anterior Cruciate Ligament and Posterolateral Corner Reconstruction An In Vivo 3-Dimensional Anatomic Study

Background: Combined anterior cruciate ligament (ACL) and posterolateral corner (PLC) injuries are relatively common, and tunnel convergence could occur in combined ACL and PLC reconstruction. Purpose: This study sought to elucidate the ranges of angles and distances of lateral collateral ligament (LCL) and popliteus tendon (PT) femoral tunnels that do not violate the intercondylar notch distally and ACL tunnels proximally during combined ACL and PLC reconstruction. Study Design: Descriptive laboratory study. Methods: Three-dimensional anatomic knee models were developed using customized software from computed tomography images of 14 patients at 0°, 90°, and 120° of flexion. Single-bundle (SB) and double-bundle (DB) ACL tunnels using the transtibial method for anteromedial bundles and the anteromedial portal method for posterolateral bundles were created. The ranges of safe angles and distances were measured at 10° and 20° posterior, neutral (0°), and 10° and 20° anterior on the horizontal plane relative to the transepicondylar axis from the isometric LCL and PT femoral insertions. The SB ACL reconstruction using the accessory medial portal and LCL reconstruction using the anatomic footprint were also analyzed. Results: Distal and proximal angles from insertions of the LCL and PT, not violating the intercondylar notch or the ACL tunnels, increased as the LCL or PT headed from a posterior to anterior direction. Safe distances from the LCL and PT femoral insertions were approximately over 35 mm distally and 30 mm proximally. For SB ACL reconstruction using the accessory medial portal, safe angles were larger proximally than those of SB ACL reconstruction using the transtibial technique. For LCL reconstruction using the anatomic footprint, proximal angles were significantly smaller than those of the isometric LCL. Conclusion: Considering the relationship between the LCL and PT tunnels and fixation strength, tunneling will be safe when the LCL and PT are positioned at an angle of approximately 20° anterior and 10° proximal to the transepicondylar axis. Clinical Relevance: These results will help to reduce the incidence of tunnel convergence in combined ACL and PLC reconstructions.

Ligament reconstruction in congenital absence of the anterior cruciate ligament: a case report.

Congenital absence of the cruciate ligament is an extremely rare condition that was first reported in Giorgis radiographic study in 1956. The authors report on a case of anterior cruciate ligament reconstruction performed on a 21-year-old female patient with congenital anterior cruciate ligament absence. We also discuss radiographic evidence that could provide clues to the congenital absence and possible difficulties that may be encountered during surgery with a review of the relevant literature.

Results of Microfracture in the Osteoarthritic Knee with Focal Full-Thickness Articular Cartilage Defects and Concomitant Medial Meniscal Tears

Purpose To evaluate the efficacy of arthroscopic microfracture in patients with focal full-thickness cartilage defects in the osteoarthritic knee. Materials and Methods Seventy-six patients were enrolled in this study. They were divided into group I (n=38) who underwent microfracture plus meniscectomy and group II (n=38) who underwent only meniscectomy. Clinical and radiological evaluations were performed. Results At the time of the three-year follow-up, a total of five failures (6.6%) were reported: four patients in group I and one in group II. The two groups showed no significant difference in the Lysholm score, the Tegner activity score and the visual analog pain scale score at three years after surgery. However, at the time of the three-month follow-up, group II showed significantly more improvement in the Tegner activity and the visual analog pain score compared with group I. Conclusions In the osteoarthritic knee, additional microfracture did not confer any additional benefit to meniscectomy.

Clavicle hook plate fixation for distal-third clavicle fracture (Neer type II): comparison of clinical and radiologic outcomes between Neer types IIA and IIB

BACKGROUND The purpose of this study was to investigate clinical and radiologic outcomes of clavicle hook plate fixation for distal-third clavicle fracture (Neer type II) and to compare the clinical and radiologic outcomes and complications between Neer type IIA and type IIB. METHODS We retrospectively reviewed 35 patients who underwent open reduction and internal fixation with AO hook locking compression plate (LCP) for distal clavicle fracture, including 13 patients with Neer type IIA and 22 patients with type IIB. Visual analog scale pain score, shoulder scores (subjective shoulder value, University of California-Los Angeles shoulder score, American Shoulder and Elbow Surgeons score), and active range of motion were evaluated to determine clinical outcome. Coracoclavicular distance was measured, and that of the injured side at last follow-up was compared with that of the uninjured side to evaluate radiologic outcomes. RESULTS AO hook LCP fixation for distal-third clavicle fracture (Neer type II) produced satisfactory radiologic outcomes, including high union rates (100%) and coracoclavicular distance maintenance, as well as satisfactory clinical outcomes, including visual analog scale score for pain, shoulder scores (subjective shoulder value, University of California-Los Angeles shoulder score, American Shoulder and Elbow Surgeons score), and active range of motion. There were no significant differences between Neer type IIA and type IIB. With regard to complications, 22.9% of patients experienced shoulder stiffness and 17.1% had subacromial erosion; however, there were no significant differences between the 2 groups. CONCLUSION The AO hook LCP is a suitable choice for Neer type IIA and type IIB distal-third clavicle fracture fixation.

Single-leaf partial meniscectomy in extensive horizontal tears of the discoid lateral meniscus: Does decreased peripheral meniscal thickness affect outcomes? (Mean four-year follow-up)

BACKGROUND To evaluate whether single-leaf partial meniscectomy in horizontal tears along the entire discoid lateral meniscus has any advantages in clinical and radiological results compared with other meniscectomies in discoid lateral meniscus. METHODS A total of 145 patients with a horizontal tear pattern in symptomatic lateral discoid meniscus were retrospectively reviewed. Twenty-seven patients had undergone full-extent single-leaf partial meniscectomy (group A), 60 had undergone conventional partial meniscectomy (saucerization) maintaining peripheral meniscal height (group B), and 58 patients had undergone total meniscectomy (group C). Each patient was evaluated with the Lysholm knee score, International Knee Documentation Committee (IKDC) subjective grading, and modified Kellgren-Lawrence grade in plain radiography at their last follow-up. RESULTS Group C had inferior functional results to groups A and B on the Lysholm knee score and IKDC subjective score. There was no significant difference between groups A and B. Group C fared significantly worse than groups A and B (p=0.003, p<0.001) by modified Kellgren-Lawrence grade. CONCLUSION With regard to clinical and radiological evaluations in lateral discoid meniscus tears, the full-extent single-leaf partial meniscectomy group had no adverse results compared with the total meniscectomy group and was not significantly different compared to the conventional partial meniscectomy group. STUDY DESIGN Cohort study. LEVEL OF EVIDENCE Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.