Greater Knee Rotatory Instability After Posterior Meniscocapsular Injury Versus Anterolateral Ligament Injury: A Proposed Mechanism of High-Grade Pivot Shift.

Background: For anterolateral rotatory instability as a result of secondary soft tissue injuries in anterior cruciate ligament (ACL)-deficient knees, there is increasing interest in secondary stabilizers to prevent internal rotation (IR) of the tibia. Purpose: To determine which secondary stabilizer is more important in anterolateral rotatory instability in ACL-deficient knees. Study Design: Controlled laboratory study. Methods: The lower extremities of 10 fresh-frozen cadavers (20 extremities) without anterior-posterior or rotational instability were included. Matched-pair randomization was performed, with each side per specimen assigned to 1 of 2 groups. In group 1, the ACL was sectioned, followed by the anterolateral ligament (ALL); in group 2, the ACL was sectioned, followed by sequential sectioning of the posterolateral meniscocapsular complex (PLMCC) and posteromedial meniscocapsular complex (PMMCC). The primary outcome was the change in relative tibial IR during a simulated pivot-shift test with 5 N·m of IR torque and 8.9 N of valgus force. The secondary outcomes were the International Knee Documentation Committee grade in the pivot-shift test and the incidence of the grade 3 pivot shift. Results: In group 1, compared with baseline, the change in relative tibial IR at 0° of knee flexion was 1.4° (95% CI, -0.1° to 2.9°; P = .052) after ALL release. In group 2, it was 2.5° (95% CI, 0.4° to 4.8°; P = .007) after PLMCC release and 4.1° (95% CI, 0.5° to 7.8°; P = .017) after combined PLMCC and PMMCC release. Combined PLMCC and PMMCC release resulted in greater change of tibial IR with statistical significance at 0°, 15°, and 30° of knee flexion (P = .008, .057, and .004, respectively) compared with ALL release. The incidence of grade 3 pivot shifts was 10% in group 1 and 90% in group 2. Conclusion: Posterior meniscocapsular laxity caused an increase in relative tibial IR as much as ALL injury in ACL-deficient knees in our simulated laboratory test, and greater anterolateral rotatory instability occurred with posterior meniscocapsular injury compared with ALL injury. Clinical Relevance: Repair of the injured posterior meniscocapsular complex may be an important treatment option for reducing anterolateral rotatory instability in the ACL-deficient knee.

Risk factors for residual popliteal cyst after arthroscopic decompression and cystectomy: Associated with degenerative cartilage lesions.

BACKGROUND: In previous studies, good results have been reported after arthroscopic treatment of popliteal cysts and concomitant intra-articular pathology. However, only a few studies have reported the associated factors with residual popliteal cysts. The aim of this study was to examine the clinical and radiographic outcomes and investigate the factors associated with the recurrence of popliteal cyst after arthroscopic cyst decompression and cyst wall resection. HYPOTHESIS: The authors hypothesized that residual popliteal cyst after arthroscopic decompression and cystectomy would be associated with degenerative cartilage lesions. PATIENTS AND METHODS: From December 2010 to December 2018, 54 patients with popliteal cysts were treated with arthroscopic decompression and cyst wall resection through an additional posteromedial cystic portal. Magnetic resonance imaging (MRI) or ultrasonography was used to observe whether the popliteal cyst had disappeared or decreased. The maximum diameter of the popliteal cyst was measured after surgery. The patients were classified into the disappeared and reduced groups according to the treatment outcome. Age, sex, symptom duration, preoperative degenerative changes based on the Kellgren-Lawrence (K-L) grade, cartilage lesions according to the International Cartilage Repair Society (ICRS) grades, synovitis, functional outcomes, and associated intra-articular lesions were compared between the two groups. The functional outcome was evaluated on the basis of the Rauschning and Lindgren knee score. The study included 22 men and 32 women, with mean age of 49.6 years (range, 5-82 years). According to the ICRS grade system, 28 (51.8%) patients had grade 0 to II, 26 (48.2%) patients had grade III to IV. RESULTS: Follow-up radiographic evaluation revealed that the cyst had completely disappeared in 20 patients (37%) and reduced in size in 34 (63%). The mean cyst size was decreased significantly from 5.7cm (range, 1.7-15cm) to 1.7cm (range, 0-6.4cm), and the Rauschning and Lindgren knee score showed improved clinical features in all the patients. Between the disappeared and reduced groups, the presence of degenerative cartilage lesions (p=0.022, odds ratio 8.702, 95% confidence interval: 1.368-55.362) showed statistically significant differences. DISCUSSION: Through the posteromedial cystic portal, cysts were completely removed in approximately 40% of patients, and the size was reduced in 60% of patients. Presence of degenerative cartilage lesion represents an associated risk factor for residual popliteal cyst. These findings could be helpful in ensuring explaining poor prognostic factors. LEVEL OF EVIDENCE: IIIb; retrospective cohort study.

Remnant Preservation of the Primary Vertical Graft in Revision Anterior Cruciate Ligament Reconstruction.

Background: The remnant preservation of a primary vertical graft in revision anterior cruciate ligament reconstruction (ACLR) can benefit anteroposterior stability. However, studies that address this concept are rare. Purpose: To evaluate clinical outcomes of remnant preservation of primary vertical graft in revision ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 74 patients with revision ACLR were included in this retrospective study. Remnant preservation revision ACLR was performed only in patients with primary vertical grafts. The patients were divided into 2 groups according to whether the primary remnant vertical graft was preserved (remnant group; n = 48) or absent or sacrificed (no-remnant group; n = 26). The remnant group was further divided according to the degree of remnant tissue: sufficiently preserved subgroup (graft coverage, ≥50%; n = 25) and insufficiently preserved subgroup (graft coverage, <50%; n = 23). Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective form, Lysholm score, Tegner activity scale, manual laxity tests, and side-to-side difference in anterior tibial translation on Telos stress radiographs. Results: The mean time to final follow-up was 40.7 ± 16.8 months. The remnant group showed more improved results in the postoperative Lachman test and Telos side-to-side difference than did the no-remnant group (P = .017 and .016, respectively). The post hoc test revealed that the side-to-side difference in laxity in the sufficiently preserved subgroup significantly outperformed that in the no-remnant group (P = .001), although no significant difference existed between the insufficiently preserved and no-remnant subgroups (P = .850). The postoperative IKDC subjective form, Lysholm score, and Tegner activity scale did not show significant differences between the 2 groups (P = .480, .277, and .883, respectively). Conclusion: The remnant preservation of the primary vertical graft in revision ACLR may result in better anteroposterior stability. However, subjective outcomes in the remnant group did not exceed that of the no-remnant group. The subgroup analysis revealed that only sufficiently preserved remnants demonstrated better anteroposterior stability.

One-Stage Anatomical Revision Anterior Cruciate Ligament Reconstruction: Results According to Tunnel Overlaps.

PURPOSE: To present clinical results according to tunnel overlap in 1-stage anatomical revision anterior cruciate ligament reconstruction (ACLR). METHODS: All patients who underwent revision ACLR performed by a single surgeon (J.H.A.) from 2012 to 2017 and were followed up for >24 months were retrospectively evaluated. The exclusion criteria were concomitant ligament injury, including medial collateral ligament injury, modified Outerbridge grade ≥3 cartilage lesion, and severe meniscus defects. Tunnel overlap was measured on 3-dimensionally reconstructed computed tomography images. Patients in the nonoverlapped femoral tunnel group (group NO, n = 52) were treated with new tunnel drilling that completely avoided previous tunnels, and those in the overlapped femoral tunnel group (group O, n = 41) were treated with a new tunnel that overlapped with previous tunnels. Clinical outcomes were evaluated using the subjective International Knee Documentation Committee (IKDC) and Lysholm scores. Knee joint stability was measured using the Lachman and pivot shift tests. Patients with femoral tunnel widening of ≥14 mm underwent 2-stage ACLR. RESULTS: The mean follow-up duration of 93 patients was 46.9 months (range, 24-97 months). All preoperative subjective and objective IKDC (P<0.001) and Telos stress test scores (P = .016) were significantly improved at the last follow-up. Forty-one patients had overlapping femoral tunnels, whereas 87 had overlapping tibial tunnels. At the last follow-up, subjective IKDC and Lysholm scores (73.6 ± 15.3 vs 74.9 ± 12.1, P = .799 and 80.0 ± 19.2 vs 81.44 ± 13.5, P = .505, respectively) and objective pivot shift (IKDC grade) in the Lachman test (P = .183 and P = .450, respectively) did not differ significantly between groups NO and O, respectively. CONCLUSIONS: One-stage anatomical revision ACLR significantly improved the clinical results. Most tibial tunnels (94%) and approximately one-half (44%) of the femoral tunnels overlapped. The overlapped femoral tunnel group did not show inferior outcomes or stability. LEVEL OF EVIDENCE: Level III, cohort study.

Discoid lateral meniscus: importance, diagnosis, and treatment.

Discoid lateral meniscus (DLM) is a common anatomic variant in the knee typically presented in young populations, with a greater incidence in the Asian population than in other populations. As DLM is a congenital anomaly, the ultrastructural features and morphology differ from those of the normal meniscus, potentially leading to meniscal tears. Snapping and pain are common symptoms, with occasional limitations of extension, in patients with DLM. Examination of the contralateral knee is necessary as DLM affects both knees. While simple radiographs may provide indirect signs of a DLM, magnetic resonance imaging (MRI) is essential for diagnosis and treatment planning. Although DLM was traditionally classified into three categories, namely, complete, incomplete, and Wrisberg DLM, a recent MRI classification provides useful information for surgical planning because the MRI classification was based on the peripheral detachment in patients with DLM, as follows: no shift, anterocentral shift, posterocentral shift, and central shift. Asymptomatic patients require close follow-up without surgical treatment, while patients with symptoms often require surgery. Total or subtotal meniscectomy, which has been traditionally performed, leads to an increased risk of degenerative arthritis; thus, partial meniscectomy is currently considered the treatment of choice for DLM. In addition to partial meniscectomy, meniscal repair of peripheral detachment is recommended for stabilization in patients with DLM to preserve the function of the meniscus. Previous studies have reported that partial meniscectomy with or without meniscal repair is effective and shows superior clinical and radiological outcomes to those of total or subtotal meniscectomy during the short- to long-term follow-up. Our preferred principle for DLM treatment is reduction, followed by reshaping with reference to the midbody of the medial meniscus and repair as firm as possible.

Arthroscopic-assisted anatomical reconstruction of the posterolateral corner of the knee joint.

Several surgical techniques have been suggested to anatomically reconstruct the posterolateral corner of the knee joint. However, most of them are open techniques that require dissection of the skin and soft tissues without utilizing the advantages of arthroscopic-assisted techniques. Therefore, this study aimed to describe a novel arthroscopic technique that anatomically reconstructs the posterolateral corner of the knee joint. This novel arthroscopic technique can properly identify important landmarks for reconstruction and anatomically reconstruct the three key components (lateral collateral ligament, popliteus tendon, and popliteofibular ligament) of the posterolateral corner of the knee joint.

Types of posterolateral corner injury associated with both bundle and selective-bundle ACL tears.

BACKGROUND: It is unknown whether a selective-bundle tear of the anterior cruciate ligament (ACL) shows a different prevalence of posterolateral corner (PLC) injury than a both-bundle tear. PURPOSE: The prevalence of injury of PLC stabilizer in relation to the type of combined ACL tear (both-bundle and selective-bundle tears) has been investigated. MATERIAL AND METHODS: This retrospective study included 94 patients who were diagnosed with an ACL tear after knee joint magnetic resonance imaging and underwent arthroscopic surgery. We compared the prevalence of each lesion in relation to the type of ACL injury and the type of selective-bundle tear. We used Fischer exact tests to compare the prevalence of each lesion in relation to the type of ACL injury and the type of selective-bundle tear. RESULTS: Both-bundle tears occurred in 55 cases (56%) and selective-bundle tears in 39 cases (44%). The most common PLC injury with an ACL tear was inferior popliteomeniscal fascicle (PMF) injury, followed by superior PMF injury. The prevalence of each PLC injury was higher for both-bundle tears than selective-bundle tears, with the exception of popliteus tendon injury diagnosed by reader 1 (P.H.J). However, these differences were statistically significant for superior PMF injury only ( p < 0.05). The prevalence of PLC injury was unrelated to the type of selective-bundle tear (anteromedial vs posterolateral). CONCLUSION: Superior PMF injury is more common in both-bundle tears than selective-bundle tears. There is no statistically significant difference in the prevalence of PLC injury between both-bundle tears and selective-bundle tears.

The usefulness of the oblique coronal plane of three-dimensional isotropic T2-weighted fast spin-echo (VISTA) knee MRI in the evaluation of posterior cruciate ligament reconstruction with allograft: Comparison with the oblique coronal plane of two-dimensional fast spin-echo T2-weighted sequences.

PURPOSE: We compared two imaging techniques to assess whether 3D VISTA imaging could replace 2D FSE in diagnosing PCL reconstruction complications. MATERIALS AND METHODS: This retrospective study included 40 patients who underwent surgery of PCL reconstruction and follow-up knee MRI (3D VISTA and 2D FSE) for evaluation of PCL graft integrity. Each image was interpreted independently by two radiologists without knowledge of radiologic reports or clinical history. The diagnostic performance of the 2D FSE PCL view, 3D VISTA PCL view, orthogonal 2D FSE image, and combined sequences were evaluated in terms of sensitivity, specificity, and accuracy for diagnosing complications of PCL graft. The reference diagnoses were made arthroscopically or clinically. RESULTS: The sensitivities of the 3D VISTA PCL view were similar to those of the 2D PCL view. The sensitivities of the combination of the orthogonal view and the 3D VISTA PCL view were also similar to those of the combination of the orthogonal view and the 2D PCL view. The specificities and accuracies of each image exhibited similar results. There was no statistically significant difference in diagnostic performance between the 3D VISTA PCL view and the 2D PCL view (solitary or combined with the orthogonal view). CONCLUSIONS: The diagnostic performance of the PCL views on 3D VISTA images is comparable to that of 2D FSE images in the diagnosis of PCL graft complications.

Arthroscopic Treatment of Diffuse Pigmented Villonodular Synovitis of the Knee: Complete Synovectomy and Septum Removal-Midterm Results.

The purpose of this study was to evaluate and describe the clinical results of complete arthroscopic synovectomy through the four arthroscopic portals in the knees affected by diffuse pigmented villonodular synovitis (DPVNS). Between 2009 and 2012, 21 patients (15 men and 6 women) with the diffuse form of PVNS of the knee were enrolled in the study after qualification. The clinical diagnosis was confirmed by magnetic resonance imaging and postsurgical pathologic examination. All patients underwent complete synovectomy through posteromedial, posterolateral, anteromedial, and anterolateral portals. Each patient was evaluated before treatment and followed up for a minimum of 5 years (range: 60-79 months) using the Lysholm score and International Knee Documentation Committee (IKDC) score. Both Lysholm score and IKDC scores were significantly improved in all study participants. No cases of clinical recurrence, infection, joint stiffness, or neurovascular lesions were observed. This study showed that an attentive arthroscopic synovectomy is a safer alternative with better clinical outcomes, with no clinical recurrences.

Evaluation of Healing After Medial Meniscal Root Repair Using Second-Look Arthroscopy, Clinical, and Radiological Criteria.

BACKGROUND: Previous studies have reported various healing rates (0%-100%) as evaluated by second-look arthroscopy after repair of medial meniscal root tears (MMRTs). Such variable results might provoke suspicion of the necessity for repair. Furthermore, the effect of meniscal healing on the clinical outcomes has not been reported. PURPOSE: To more precisely determine the healing rate of MMRTs repaired through the transseptal portal, which could provide objective visualization of the healed meniscus, and to identify the effect of meniscal healing on the clinical and radiological outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between June 2010 and April 2015, 56 patients underwent pullout suture for MMRT. Lysholm score, Hospital for Special Surgery score, International Knee Documentation Committee subjective score, medial joint space height, and Kellgren-Lawrence (K-L) grade were evaluated. Thirty-three patients underwent second-look arthroscopy and were divided into a "stable healed group" and "unhealed group" according to their healing status, as evaluated through the transseptal portal. The intraoperative, clinical, and radiological outcomes of the 2 groups were compared. RESULTS: All other clinical outcomes improved. However, medial joint space became significantly narrower ( P < .001), and 23 patients (41%) showed K-L grade progression. On the basis of second-look arthroscopy, 23 patients (69.7%) were classified into a stable healed group and 10 (30.3%) into a unhealed group. The stable healed group showed a higher Hospital for Special Surgery score ( P = .023), International Knee Documentation Committee subjective score ( P = .031), and successful microfracture rate ( P = .023), with less progression of medial joint space narrowing ( P < .001) and K-L grade ( P < .001). CONCLUSION: Despite degenerative change progression, clinical outcomes were improved. The successful healing rate was 69.7% after repair of MMRTs. Compared with the unhealed group, the stable healed group showed better clinical outcomes and less degenerative change progression.

Magnetic Resonance Imaging and Clinical Results of Outside-in Anterior Cruciate Ligament Reconstruction: A Comparison of Fixed- and Adjustable-Length Loop Cortical Fixation.

BACKGROUND: Cortical suspensory femoral fixation is commonly performed for graft fixation to the femur in anterior cruciate ligament (ACL) reconstruction using hamstring tendons. The purpose of this study was to compare graft healing in the femoral tunnel, implant-related failure, and clinical results between fixed- and adjustable-length loop devices in outside-in ACL reconstruction. METHODS: A total of 109 patients who underwent ACL reconstruction using the outside-in technique from December 2010 to July 2014 were included. For femoral graft fixation, a fixed-length loop device was used in 48 patients (fixed-loop group) and an adjustable-length loop device was used in 61 patients (adjustable-loop group). For evaluation of graft healing in the femoral tunnel, magnetic resonance imaging was performed at postoperative 6 months and the signal-to-noise ratios (SNRs) of the tendon graft and tendon-bone interface in the femoral bone tunnel were evaluated. The presence of synovial fluid was evaluated to determine loop lengthening at the femoral tunnel exit. Clinical results assessed using International Knee Documentation Committee score, Tegner-Lysholm Knee Scoring scale, and knee instability tests were compared between groups. RESULTS: The SNRs of the tendon graft and tendon-bone interface were not statistically different between groups. The presence of synovial fluid at the femoral exit showed no statistical difference between groups. Clinical results were not significantly different between groups. CONCLUSIONS: The adjustable-length loop device provided comparable graft healing, implant-related failure, and clinical results with the fixed-length loop device, allowing adaptation of the graft to the different tunnel lengths. Therefore, it could be effectively used with an adjustment according to the femoral tunnel length.

Arthroscopic meniscus repair for recurrent subluxation of the lateral meniscus.

PURPOSE: This study was undertaken to diagnose and to document the clinical results and technical aspects of arthroscopic meniscus repair for recurrent subluxation with peripheral tears around the popliteal hiatus of the lateral meniscus. METHODS: Twenty-three patients (24 knees) with symptomatic recurrent subluxation of the lateral meniscus treated by arthroscopic meniscus repair were included. The inclusion criteria were: (1) patients with knee pain, locking or snapping symptoms despite 3 months of conservative treatment; (2) non-discoid lateral meniscus; (3) stable knee, and (4) tears involving the red-white or red-red zone. All tears were repaired by either the modified all-inside suture technique only or a combination of the modified all-inside and modified outside-in suture techniques. Clinical results were evaluated preoperatively and at final follow-up according to Tegner activity level, Lysholm knee, and Hospital for Special Surgery (HSS) scores. RESULTS: No reoperations were required after a median follow-up of 41 months (range 24-124). Although recurrence of a locking episode was documented in one knee and catching sensations were experienced in three knees, those patients did not require reoperation. At the last follow-up, the median Tegner activity level had improved significantly from 4 (range 2-6) to 7 (range 3-10, p < 0.0001), the median Lysholm knee score improved from 76 (range 25-90) preoperatively to 94 (range 76-100) at final follow-up (p < 0.0001), and the median preoperative HSS score improved from 86 to 95 at final follow-up (p < 0.0001). CONCLUSION: The described arthroscopic meniscus suture technique is effective for treating symptomatic recurrent subluxation of the lateral meniscus without any complications or recurrence. Clinical suspicion and understanding of recurrent subluxation with lateral meniscus are important to diagnose the disease especially when definite meniscal tear signs are absent on magnetic resonance imaging. LEVEL OF EVIDENCE: IV.

Effectiveness of concurrent procedures during high tibial osteotomy for medial compartment osteoarthritis: a systematic review and meta-analysis.

INTRODUCTION: The purpose of this systematic review and meta-analysis was to evaluate the efficacy of concurrent cartilage procedures during high tibial osteotomy (HTO) for medial compartment osteoarthritis (OA) by comparing the outcomes of studies that directly compared the use of HTO plus concurrent cartilage procedures versus HTO alone. MATERIALS AND METHODS: Results that are possible to be compared in more than two articles were presented as forest plots. A 95% confidence interval was calculated for each effect size, and we calculated the I 2 statistic, which presents the percentage of total variation attributable to the heterogeneity among studies. The random effects model was used to calculate the effect size. RESULTS: Seven articles were included to the final analysis. Case groups were composed of HTO without concurrent procedures and control groups were composed of HTO with concurrent procedures such as marrow stimulation procedure, mesenchymal stem cell transplantation, and injection. The case group showed a higher hospital for special surgery score and mean difference was 4.10 [I 2 80.8%, 95% confidence interval (CI) - 9.02 to 4.82]. Mean difference of the mechanical femorotibial angle in five studies was 0.08° (I 2 0%, 95% CI - 0.26 to 0.43). However, improved arthroscopic, histologic, and MRI results were reported in the control group. CONCLUSION: Our analysis support that concurrent procedures during HTO for medial compartment OA have little beneficial effect regarding clinical and radiological outcomes. However, they might have some beneficial effects in terms of arthroscopic, histologic, and MRI findings even though the quality of healed cartilage is not good as that of original cartilage. Therefore, until now, concurrent procedures for medial compartment OA have been considered optional. Nevertheless, no conclusions can be drawn for younger patients with focal cartilage defects and concomitant varus deformity. This question needs to be addressed separately.

A Comparative Biomechanical Study of Femoral Cortical Suspension Devices for Soft-Tissue Anterior Cruciate Ligament Reconstruction: Adjustable-Length Loop Versus Fixed-Length Loop.

PURPOSE: To determine whether there are differences between adjustable-length loop and fixed-length loop devices in terms of the amount of displacement, temporal pattern of displacement, and ultimate failure load when tested using 4,500 cycles of sinusoidal loading with high loads (100-400 N). METHODS: Two cortical suspension devices with a fixed- or adjustable-length loop were tested. For our comparisons, a 20-mm fixed-length loop device and a fixed-length loop device with the same loop length were used. Comparisons between the devices used both a device-only model (DOM) and a device-bone-soft-tissue graft construct model (CM). RESULTS: In the DOM, the adjustable-length loop device showed weaker mechanical properties. Mean cumulative peak displacement was 1.91 mm for the adjustable-length loop device and 0.74 mm for the fixed-length loop device (P = .001). The displacement of the adjustable-length loop device increased between 1,000 and 4,500 cycles; in contrast, that of the fixed-length loop device reached a plateau. However, there was never displacement greater than 3 mm. In addition, the adjustable-length loop device showed a weaker ultimate failure load (925 N vs 1,410 N, P = .001). In the CM, the difference in cumulative peak displacement between the 2 groups decreased and did not reach statistical significance. The displacement of both devices showed a similar pattern. In addition, there was no difference in ultimate failure load between the 2 groups. CONCLUSIONS: There was no significant difference in terms of total displacement, temporal pattern of displacement, and ultimate failure load between the 2 devices in the CM, which is the more clinically relevant model. Furthermore, even in the DOM, the difference in total displacement was small and did not reach a clinically meaningful level. Therefore, both devices can be used effectively during anterior cruciate ligament reconstruction with soft-tissue graft. CLINICAL RELEVANCE: Both femoral cortical suspension devices with adjustable- and fixed-length loops can be used with similar mechanical properties during anterior cruciate ligament reconstruction.

Evaluation of Selective Bundle Injury to the Anterior Cruciate Ligament: T2-Weighted Fast Spin-Echo 3-T MRI With Reformatted 3D Oblique Isotropic (VISTA) Versus 2D Technique.

OBJECTIVE: The purpose of this study was to compare the diagnostic utility of oblique sagittal and oblique coronal 3D volume isotropic turbo spin-echo acquisition (VISTA) images with that of 2D fast spin-echo (FSE) T2-weighted images in the diagnosis of selective bundle tears of the anterior cruciate ligament (ACL). MATERIALS AND METHODS: This retrospective study included 56 patients who underwent 2D FSE and 3D VISTA 3-T MRI of the knee before arthroscopic procedures. Images obtained with the two sequences were interpreted by two musculoskeletal radiologists independently, and the results were analyzed with the surgical diagnosis as the reference. RESULTS: Among the 56 patients with suspected ACL injury, the arthroscopic records revealed 14 cases (25%) of complete tear, four cases (7%) of selective posterolateral bundle tear, and three cases (5%) of selective anteromedial bundle tear. The contrast-to-noise ratio between the ACL and joint fluid for 3D VISTA was 1.97 times as high as that for 2D FSE (p < 0.001). The entire width evaluation and margin sharpness scores for 2D FSE were significantly higher than those for 3D VISTA for both readers (p < 0.05). No significant differences were found in sensitivity, specificity, or accuracy of 2D FSE and 3D VISTA in the diagnosis of selective ACL tears (p > 0.05). CONCLUSION: The diagnostic utility of oblique sagittal and oblique coronal 3D VISTA sequences was similar to that of 2D FSE sequences in the MRI diagnosis of selective bundle tear of the ACL, but the image quality of 3D VISTA was inferior to that of 2D FSE.

Does high location and thickness of the Wrisberg ligament affect discoid lateral meniscus tear type based on peripheral detachment?

BACKGROUND: The aim of this study was to evaluate the relationship between discoid lateral meniscus (DLM) types based on peripheral detachment and anatomic features of Wrisberg ligament (WL) such as location and thickness based on magnetic resonance image (MRI). METHODS: A total of 322 knees in 292 patients were reviewed. Patients were divided into four DLM types according to peripheral detachment: no shift (type 1), anterocentral shift (type 2), posterocentral shift (type 3) and central shift (type 4). We reviewed all MRI concentrating on the presence, location (high or low location), running angle, thickness of WL, and WL/posterior cruciate ligament (PCL) thickness ratio. The relationship between DLM types and anatomic features of WL were analyzed using one-way analysis of variance and chi-square test. RESULTS: According to DLM types based on peripheral detachment, 149 knees were type 1, 38 were type 2, 79 were type 3, and 56 were type 4. Among the 322 knees, 302 (93.8%) had WL on MRI. In DLM patients, type 3 showed a statistically significant (P<0.001) relationship with high location of WL. In addition, type 3 had significantly larger (P<0.0001) running angle of WL, thicker (P<0.0001) WL, and higher (P<0.0001) WL/PCL ratio compared to other types. CONCLUSION: A high location and thick WL are related to posterocentral shift type of DLM based on peripheral detachment. Based on our results, the high location and thick WL might provide information to surgeons in predicting the direction of peripheral detachment in symptomatic DLM patients.

Systematic Review of the Long-term Surgical Outcomes of Discoid Lateral Meniscus.

PURPOSE: To evaluate the surgical treatment of the discoid lateral meniscus (DLM) with long-term follow-up and to search which factors are related to good clinical or radiological outcomes. METHODS: Search was performed using a MEDLINE, EMBASE, and Cochrane database, and each of the selected studies was evaluated for methodological quality using a risk of bias (ROB) covering 7 criteria. Clinical and radiological outcomes with more than 5 years of follow-up were evaluated after surgical treatment of DLM. They were analyzed according to the age, follow-up period, kind of surgery, DLM type, and alignment. RESULTS: Eleven articles (422 DLM cases) were included in the final analysis. Among 7 criteria, 3 criteria showed little ROB in all studies. However, 4 criteria showed some ROB ("Yes" in 63.6% to 81.8%). The minimal follow-up period was 5.5 years (weighted mean follow-up: 9.1 years). Surgical procedures were performed with open or arthroscopic partial central meniscectomy, subtotal meniscectomy, total meniscectomy, or partial meniscectomy with repair. The majority of the studies showed good clinical results. Mild joint space narrowing was reported in the lateral compartment, but none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy could be related to degenerative change. The majority of the complications was osteochondritis dissecans at the lateral femoral condyle (13 cases) and reoperation was performed by osteochondritis dissecans (4 cases), recurrent swelling (2 cases), residual symptom (1 case), stiffness (1 case), and popliteal stenosis (1 case). CONCLUSIONS: Good clinical results were obtained with surgical treatment of symptomatic DLM. The progression of degenerative change was minimal and none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy were possible risk factors for degenerative changes. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.

Comparison of transtibial and retrograde outside-in techniques of anterior cruciate ligament reconstruction in terms of graft nature and clinical outcomes: a case control study using 3T MRI.

INTRODUCTION: This study was performed to compare ACL graft maturation and morphologies using MRI between trans-tibial (TT) and retrograde outside-in (OI) techniques, and to compare clinical outcomes between the two groups. MATERIALS AND METHODS: Patients underwent single-tunnel ACL reconstruction using quadrupled hamstring autografts, with the TT technique used on 42 patients (TT group) and the retrograde OI technique used on 39 patients (OI group). All patients were examined with 3 T MRI at 6 months (between 5 and 7 months) after surgery. The signal intensity of the reconstructed graft was analyzed and compared between the two groups, using the signal/noise quotient (SNQ), the orientation of the ACL graft and the tibial tunnel location of the graft. The SNQ value is indicative of graft maturation, and the orientation of the graft and the tibial tunnel location of the graft represent graft morphology. Clinical evaluation was performed before the surgery and 2 years or more after the surgery. RESULTS: The mean SNQ value of the TT group was significantly (P = 0.030) lower than that of the OI group. The mean sagittal ACL angle (P < 0.001) and the mean coronal ACL angle (P < 0.001) were more vertical in the TT group. The tibial tunnel aperture was located at a significantly (P < 0.001) more posterior position in the TT group. There was no statistically significant difference in the clinical results between the two groups. CONCLUSIONS: The OI technique showed a more anteriorly positioned tibial tunnel and a more oblique graft orientation in both sagittal and coronal planes. However, in comparison with the TT group, a significantly higher SNQ value was noticed in the follow-up MRI of the OI group at 6 months, although clinical results of the two groups were not significantly different during at least the 2-year follow-up.

Arthroscopic all-inside ramp lesion repair using the posterolateral transseptal portal view.

PURPOSE: The purpose of this study was to evaluate and describe the clinical results and outcomes of a novel method for all-inside suture repair of medial meniscus ramp lesions through posteromedial and posterolateral transseptal portals during anterior cruciate ligament (ACL) reconstruction. Further, this investigation compared the posterolateral view to the notch view for diagnosis and repair. METHODS: Between 2011 and 2014, 166 patients had ramp lesions concomitantly with ACL injury; 128 patients (107 men and 21 women) were enrolled in the study after qualification. All patients underwent repair of the posterior horn ramp lesion of the medial meniscus, using a suture hook device with PDS No. 1 through a posteromedial portal while viewing from the posterolateral transseptal portal during ACL reconstruction, with a minimum of a 2-year follow-up. RESULTS: Patients were followed up for a minimum of 2 years (range 24-47 months). Their average Lysholm score increased from 61.7 ± 3.2 preoperatively to 87.8 ± 3.9 at last follow-up (p < 0.001). Moreover, their average IKDC scores also improved from 53.6 ± 2.1 (pre-op) to 82.1 ± 3.5 (at last follow-up) (p < 0.001). The peroneal nerve and the popliteal neurovascular bundle were not damaged in any of the patients. CONCLUSION: This study provides evidence that the posterolateral transseptal technique protects neurovascular structures. This technique may be used safely and easily for repair of the posterior horn ramp lesion of the medial meniscus during ACL reconstruction. LEVEL OF EVIDENCE: IV.