More than 3 mm of preoperative medial meniscal extrusion is identified as a key risk factor for varus progression in limb alignment after arthroscopic repair of medial meniscus posterior root tear.

PURPOSE: To investigate the risk factors for varus progression after arthroscopic medial meniscal posterior root tear (MMPRT) repair and to compare the clinical outcomes between two groups: one with more varus progression and the other with less varus progression. METHODS: Patients who underwent isolated arthroscopic repair of MMPRT between 2015 and 2020 were enroled, and 2-year follow-up data were collected. Participants were categorized into two groups based on preoperative values of the weight-bearing line (WBL) ratio: group A with <5.9% increase and group B with ≥5.9% increase. Various factors, including demographic features and radiological findings, were analysed and compared between the two groups. Intra-meniscal signal intensity, meniscal healing, medial meniscal extrusion (MME), and articular cartilage grade were assessed preoperatively and 1-year postoperatively using coronal magnetic resonance imaging. RESULTS: The final cohort consisted of 34 patients in group A and 46 in group B, with a mean age of 55.8 ± 11.2 and 59.8 ± 6.6 years, respectively. Preoperative WBL ratio and cartilage lesions in the medial compartment did not differ between the groups. Preoperative MME were significantly lower in group A than those in group B (2.6 ± 0.6 mm in group A and 3.5 ± 0.7 mm in group B, p < 0.05). Patient-reported outcomes at the 2-year follow-up did not differ between the two groups (n. s.). In a logistic analysis, the odds ratio of MME was 2.1 (p < 0.05), and the cutoff value of MME was 3.02 mm. CONCLUSION: Preoperative MME is a risk factor for varus progression. However, no differences in patient-reported outcomes were observed at 2-year follow-up, even in the group with greater varus progression. LEVEL OF EVIDENCE: Level IV.

Anatomic femoral tunnel position in medial patellofemoral ligament reconstruction: anterior versus posterior.

BACKGROUND: This study aimed to compare the clinical and radiological outcomes of medial patellofemoral ligament reconstruction (MPFLR) between anatomic femoral tunnel positions at anterior and posterior footprints. METHODS: Fifty-seven patients who underwent MPFLR for patellofemoral instability with anterior or posterior femoral tunnels between 2014 and 2021 with at least 2 years of follow-up were retrospectively analyzed. Based on postoperative images, the femoral tunnel positions anterior to the line connecting the adductor tubercle and medial epicondyle were assigned to the anterior group, group A, and those posterior to the line to the posterior group, group P. Thirty-two patients were included in group A (mean age, 22.4 ± 8.8 years), and another 25 patients were included in group P (mean age, 21.1 ± 6.1 years). The International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity score, Kujala score, and complications were evaluated. Radiologically, the Caton-Deschamps index (CDI), patellar tilt angle, and patellofemoral osteoarthritis (PFOA) using the Kellgren-Lawrence (KL) scale were evaluated. The patellofemoral cartilage status according to the International Cartilage Repair Society (ICRS) grade, bone contusion, femoral tunnel enlargement, and MPFL graft signal intensity were also evaluated. RESULTS: All clinical scores significantly improved in both groups (p < 0.01). No differences were noted between the two groups in terms of their preoperative demographic data, postoperative clinical scores (IKDC, Lysholm, Tegner, and Kujala), complications, or radiological findings (CDI, patellar tilt angle, PFOA, bone contusion, femoral tunnel enlargement, and graft signal intensity). The ICRS grade for the medial facet of the patella progressed in group A (30%, p = 0.02) but not in group P (18%, p = n.s.). Additionally, no significant differences were observed in the other compartments of the patellofemoral joint. CONCLUSIONS: The clinical outcomes were significantly improved in both groups; however, MPFLR with anterior femoral tunnel position had worse cartilage status on the medial facet of the patella than the posterior femoral tunnel position. LEVEL OF EVIDENCE: Level III.

Outcomes of Arthroscopic All-Inside Repair Are Improved Compared to Transtibial Pull-Out Repair of Medial Meniscus Posterior Root Tears.

PURPOSE: The purpose of the present study was to compare the clinical outcomes of patients who underwent an all-inside repair (with a bony trough) versus transtibial pull-out repair in medial meniscus posterior root tears (MMPRTs). METHODS: We retrospectively investigated consecutive patients who underwent MMPRT repairs in nonacute tears in age over 40 from November 2015 to June 2019. All patients were divided into a transtibial pull-out repair group and an all-inside repair group. Different surgical techniques were used during different time frames. All patients were followed-up for a minimum of 2 years. The data collected included the International Knee Documentation Committee (IKDC) Subjective, Lysholm, and Tegner activity scores. Magnetic resonance imaging (MRI) was performed at the 1-year follow-up to assess meniscus extrusion, signal intensity, and healing. RESULTS: The final cohort consisted of 28 patients in the all-inside repair group and 16 in the transtibial pull-out repair group. In the all-inside repair group, the IKDC Subjective, Lysholm, and Tegner scores improved significantly at the 2-year follow-up. In the transtibial pull-out repair group, the IKDC Subjective, Lysholm, and Tegner scores did not improve significantly at the 2-year follow-up. Postoperative extrusion ratio increased in both groups, and patient-reported outcomes at follow-up did not differ between the two groups The change in the extrusion ratio was significantly less in the all-inside repair group (P = .009), as was the postoperative meniscus signal (P = .011). Postoperative MRI revealed significantly better healing in the all-inside group (P = .041). CONCLUSION: All-inside repair improved the functional outcome scores. Radiologically, all-inside repair was better than transtibial pull-out repair. All-inside repair may be a viable MMPRT treatment option. LEVEL OF EVIDENCE: III, retrospective cohort study.

Reprint of: Outcomes of Arthroscopic All-Inside Repair Are Improved Compared to Transtibial Pull-Out Repair of Medial Meniscus Posterior Root Tears.

PURPOSE: The purpose of the present study was to compare the clinical outcomes of patients who underwent an all-inside repair (with a bony trough) versus transtibial pull-out repair in medial meniscus posterior root tears (MMPRTs). METHODS: We retrospectively investigated consecutive patients who underwent MMPRT repairs in nonacute tears in age over 40 from November 2015 to June 2019. All patients were divided into a transtibial pull-out repair group and an all-inside repair group. Different surgical techniques were used during different time frames. All patients were followed-up for a minimum of 2 years. The data collected included the International Knee Documentation Committee (IKDC) Subjective, Lysholm, and Tegner activity scores. Magnetic resonance imaging (MRI) was performed at the 1-year follow-up to assess meniscus extrusion, signal intensity, and healing. RESULTS: The final cohort consisted of 28 patients in the all-inside repair group and 16 in the transtibial pull-out repair group. In the all-inside repair group, the IKDC Subjective, Lysholm, and Tegner scores improved significantly at the 2-year follow-up. In the transtibial pull-out repair group, the IKDC Subjective, Lysholm, and Tegner scores did not improve significantly at the 2-year follow-up. Postoperative extrusion ratio increased in both groups, and patient-reported outcomes at follow-up did not differ between the two groups The change in the extrusion ratio was significantly less in the all-inside repair group (P = .009), as was the postoperative meniscus signal (P = .011). Postoperative MRI revealed significantly better healing in the all-inside group (P = .041). CONCLUSION: All-inside repair improved the functional outcome scores. Radiologically, all-inside repair was better than transtibial pull-out repair. All-inside repair may be a viable MMPRT treatment option. LEVEL OF EVIDENCE: III, retrospective cohort study.

Closed-wedge high tibial osteotomy is more advantageous to maintain the correction than open-wedge high tibial osteotomy in osteopenic patients.

PURPOSE: To compare the incidence of correction loss and survival rate between closed-wedge and open-wedge high tibial osteotomies (CWHTO and OWHTO, respectively) in patients with osteopenic and normal bone. METHODS: Retrospective review was conducted for 115 CWHTOs and 119 OWHTOs performed in osteopenic patients [- 2.5 < Bone mineral density (BMD) T scores ≤ - 1] and 136 CWHTOs and 138 OWHTOs performed in normal patients (BMD T score > - 1) from 2012 to 2019. Demographics were not different between CW- and OWHTOs in osteopenic and normal patients (n.s., respectively). Radiographically, the mechanical axis (MA), medial proximal tibial angle (MPTA), and posterior tibial slope (PTS) were evaluated pre- and postoperatively (2 weeks after HTO). The occurrence of hinge fractures was investigated using radiographs taken on the operation day. The correction change was calculated as the last follow-up value minus postoperative MPTA. Correction loss was defined when the correction change was ≥ 3°. The survival rate (failure: correction loss) was investigated. RESULTS: There were no significant differences in the pre and postoperative MA, MPTA, PTS, and value changes between CW- and OWHTOs in osteopenic and normal patients (n.s., respectively); the incidence of unstable hinge fractures also did not differ significantly (CWHTO vs. OWHTO = 7 vs. 7.6% in osteopenic patients; 2.9 vs. 3.6% in normal patients; n.s., respectively). The average correction change (CWHTO = - 0.6°, OWHTO = - 1.3°, p = 0.007), incidence of correction loss (CWHTO = 1.7%, OWHTO = 9.2%, p = 0.019), and 5-year survival rates (CWHTO = 98.3%, OWHTO = 90.8%, p = 0.013) differed significantly in osteopenic patients; there were no significant differences in these results in normal patients (n.s., respectively). CONCLUSION: CWHTO was more advantageous than OWHTO regarding the correction loss in osteopenic patients. Intra- and postoperative care that consider poor bone quality will be required when performing OWHTOs in osteopenic patients. LEVEL OF EVIDENCE: III.

Costal chondrocyte-derived pellet-type scaffold-free autologous chondrocyte implantation provided acceptable mid-term outcomes in osteochondral defects with up to 10-mm depth.

PURPOSE: To evaluate clinical, radiographic, and magnetic resonance (MR) results of costal chondrocyte-derived pellet-type scaffold-free autologous chondrocyte implantation (CCP-ACI) in osteochondral defects (ODs) up to 10-mm depth during 5 years of follow-up. METHODS: Ten patients with CCP-ACI performed in ODs with depth up to 10 mm were retrospectively analyzed. The minimum follow-up period was 5 years. The median age was 36.5 (range 20-55) years. The median size and the depth of the OD lesion were 4.25 cm2 (range 2-6) and 7.0 mm (6-9), respectively. Clinically, the International Knee Documentation Committee, Lysholm, and visual analog scale pain scores were evaluated. Radiographically, the hip‒knee‒ankle (HKA) angle and the Kellgren‒Lawrence (K‒L) grade were assessed. On MR imaging, the magnetic resonance observation of cartilage repair tissue (MOCART) 2.0 score and the defect depth were evaluated. RESULTS: All average clinical scores improved significantly by 1, 2, and 5 years postoperatively. The average HKA angle and the proportion of K‒L grade did not change significantly within 5 years. The median total MOCART scores were 50 (range 45-65), 50 (35-90), 57.5 (40-90), and 65 (50-85) at 6 months, 1 year, 2 years, and 5 years postoperatively, respectively (p = 0.001), with significant improvement at 2 years compared to that at 6 months postoperatively. The signal intensity of the repair tissue and subchondral change significantly improved from 10 (range 10-10) to 12.5 (10-15) (p = 0.036), and from 10 (10-10) to 17.5 (0-20) (p = 0.017), respectively. Significant improvements were seen at 5 years postoperatively for the former and at 2 years postoperatively for the latter. The average depths on MR imaging were 6.7, 6.7, 6.8, 6.6, and 6.6 mm preoperatively and at 6 months, 1 year, 2 years, and 5 years postoperatively with no significant changes (n.s). CONCLUSION: CCP-ACI provided acceptable mid-term outcomes in ODs up to 10-mm in depth without bone grafting despite of no scaffold. The procedure can be one of minimally invasive treatment options for ODs without scaffold-related problems. LEVEL OF EVIDENCE: IV.

Additional anteromedial staple fixation prevents changes in the posterior tibial slope in retrotuberosity bi-planar open-wedge high tibial osteotomy.

PURPOSE: To compare the changes in posterior tibial slope (PTS) between retrotuberosity biplane open-wedge high tibial osteotomies (RT-OWHTOs) with and without additional anteromedial staple fixation. METHODS: Seventy-nine and 77 cases of RT-OWHTOs without (Group N) and with (Group S) additional staple fixation, respectively, were retrospectively reviewed. All procedures were performed using a locking spacer plate. Demographics and preoperative knee condition were similar between the groups. Clinically, the Western Ontario and McMaster Universities Arthritis Index and range of motion were evaluated preoperatively and 2 years postoperatively. Radiographically, the mechanical axis (MA), medial proximal tibial angle (MPTA), and PTS were evaluated preoperatively and within 2 years postoperatively. Hinge fractures were investigated using computed tomography at 2 weeks postoperatively. PTS loss was defined as the difference between the corresponding values at 2 weeks and 2 years postoperatively. The incidence of PTS failure (PTS loss ≥ ± 3°) was also investigated. RESULTS: The clinical results were not significantly different between groups N and S preoperatively and 2 years postoperatively. There were no significant differences in the MA, MPTA, and PTS between the groups preoperatively and 2 weeks postoperatively; changes in these variables did not differ significantly between the groups. The incidence of hinge fractures, all of which were categorized as Takeuchi type 1, did not differ significantly. PTS loss within 2 years postoperatively was significantly greater in group N than in group S (1.0° vs. 0.1°; p < 0.01). The incidence of the PTS failure was 16.5% (13/79) and 2.6% (2/77) in groups N and S, respectively (p < 0.01). CONCLUSION: Additional anteromedial staple fixation could prevent changes in the PTS in RT-OWHTO. It is a simple method for preventing an increase in the PTS after RT-OWHTO. LEVEL OF EVIDENCE: III.

The efficacy of intraarticular viscosupplementation after arthroscopic partial meniscectomy: a randomized controlled trial.

BACKGROUND: This study aimed to evaluate the efficacy of viscosupplementation after arthroscopic partial meniscectomy. METHOD: A randomized controlled trial of 47 patients who underwent arthroscopic partial meniscectomy was conducted between March 2020 and March 2021. Patients were randomized into two groups: a viscosupplementation group (n = 23) and a control group (n = 24). A single-dose intraarticular hyaluronic acid injection was used as viscosupplementation. The 100 mm visual analogue scale (VAS) for pain assessment was measured at baseline and at 1 day, 2 weeks, 6 weeks, and 3 months post-surgery. The International Knee Documentation Committee (IKDC), Tegner, Lysholm, and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) scores and range of motion (ROM) of the knee were measured at baseline, 2 weeks, 6 weeks, and 3 months. RESULTS: The 100 mm VAS score for pain was significantly lower in the viscosupplementation group at 2 weeks post-surgery (27.5 mm vs. 40.7 mm, P = 0.047). ROM was significantly greater in the viscosupplementation group than in the control group at 2 weeks (131.5° vs. 121.0°, P = 0.044) post-surgery. No significant differences were observed in the IKDC or in the Tegner, Lysholm, and WOMAC scores between the two groups. CONCLUSIONS: Viscosupplementation after arthroscopic partial meniscectomy significantly reduced pain at 2 weeks post-surgery and improved ROM of the knee at 2 weeks post-surgery. There might be some benefits in terms of pain and functional recovery of viscosupplementation after arthroscopic surgery. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. TRIAL REGISTRATION: This randomized controlled trial was registered at cris.nih.go.kr # KCT0004921 .

The amount of displacement can determine non-operative treatment in posterior cruciate ligament avulsion fracture.

PURPOSE: It is generally agreed that surgical treatment is warranted for acute posterior cruciate ligament (PCL) avulsion fracture with displacement. However, the amount of displacement that warrants surgical treatment has not been defined. The purpose of this study was to determine the optimal cut-off value for displacement of posterior cruciate ligament avulsion fracture in determining non-operative treatment and to compare the results of non-operative treatment in acute isolated PCL avulsion fractures with non-operative treatment of acute PCL injury. METHODS: Between 2007 and 2017, 30 consecutive patients with acute isolated PCL avulsion fractures and 70 consecutive patients with acute isolated PCL injuries, all of whom underwent non-operative treatment (cast immobilization with > 2 years of follow-up) were retrospectively analyzed. Clinical scores including the International Knee Documentation Committee subjective score, Lysholm score, and Tegner activity score, as well as side-to-side differences on stress radiographs, were compared between the PCL avulsion fracture and PCL injury groups at the final follow-up. The failure rates of non-operative treatment were also compared. The predictive value of the amount of fracture displacement for successful non-operative treatment was calculated using area under the receiver operating characteristic curve (AUROC). The optimal cut-off of the amount of fracture displacement to determine non-operative treatment was based on the maximal sum of sensitivity and specificity. RESULTS: The two groups exhibited comparable clinical scores and mean side-to-side differences on stress radiographs. There were 5 (16.6%) failures of non-operative treatment in the PCL avulsion fracture group and 19 (27.1%) failures in the PCL injury group. (n.s) There was a significant positive correlation between the amount of initial avulsion fracture displacement and side-to-side difference in posterior stress radiographs at final follow up (P < 0.001). The optimal cut-off value for the amount of fracture displacement in PCL avulsion fracture to predict failure of non-operative treatment was 6.7 mm (AUROC = 1.0). CONCLUSION: The outcomes of non-operative treatment of acute isolated PCL avulsion fractures were comparable to those of patients with acute isolated PCL injuries. Acute PCL avulsion injuries with displacement of less than 6.7 mm should be considered for non-operative treatment. LEVEL OF EVIDENCE: IV.

Comparable clinical and radiological outcomes between anatomical and high femoral tunnels in posterior cruciate ligament reconstruction.

PURPOSE: To compare clinical and radiological outcomes and failure rates between anatomical and high femoral tunnels in remnant-preserving single-bundle posterior cruciate ligament (PCL) reconstruction. METHODS: 63 patients who underwent remnant-preserving single-bundle PCL reconstruction between 2011 and 2018 with a minimum 2-year follow-up were retrospectively reviewed. Patients were divided into two groups according to the femoral tunnel position: group A (33 patients with anatomical femoral tunnel) and group H (30 patients with high femoral tunnels). The femoral tunnel was positioned at the center (group A) or upper margin (group H) of the remnant anterolateral bundle. The position of the femoral tunnel was evaluated using the grid method on three-dimensional computed tomography. Clinical and radiological outcomes and failure rates were compared between the groups at the 2-year follow-up. RESULTS: The position of the femoral tunnel was significantly high in group H than in group A (87.4% ± 4.2% versus 76.1% ± 3.7%, p < 0.001). Clinical outcomes were not significantly different between the two groups in terms of the clinical scores (International Knee Documentation Committee subjective, Lysholm, and Tegner activity scores), range of motion, and posterior drawer test. Radiological outcomes also showed no intergroup differences in the side-to-side differences of posterior tibial translation and osteoarthritis progression. Side-to-side difference on the Telos stress radiograph was 5.2 ± 2.9 mm in group A and 5.2 ± 2.7 mm in group H (n.s.). There were four failures in group A (12.1%) and one in group H (3.3%). The differences between the groups were not statistically significant. CONCLUSION: The clinical and radiological outcomes and failure rates of the high femoral tunnels were comparable with those of the anatomical femoral tunnels at the 2-year follow-up after remnant-preserving single-bundle PCL reconstruction. The findings of this study suggest that high femoral tunnels can be considered an alternative in remnant-preserving single-bundle PCL reconstruction. LEVEL OF EVIDENCE: III.

Clinical Outcomes and the Failure Rate of Revision Anterior Cruciate Ligament Reconstruction Were Comparable Between Patients Younger Than 40 Years and Patients Older Than 40 Years: A Minimum 2-Year Follow-Up Study.

PURPOSE: To compare the clinical outcomes and failure rates of revision anterior cruciate ligament reconstruction (ACLR) between young and middle-aged surgery patients. METHODS: Patients who underwent revision ACLRs between January 2008 and June 2017 with a minimum 2-year follow-up were retrospectively evaluated. Patients were divided into 2 groups according to age: ≥40 years (group A) and <40 years (group B). Detailed patient demographic data, preoperative radiographic data, and concurrent meniscal and chondral lesion were reviewed. Clinical scores, laxity tests results, and graft failures were compared between groups at the final follow-up. RESULTS: Eighty-six patients (group A, n = 24, 46.6 ± 4.5 years; group B, n = 62, 26.2 ± 6.3 years) were included in this study. Demographic data showed that the time interval from primary to revision ACLR was longer in group A than in group B (96.2 ± 80.9 vs. 52.0 ± 42.1 months, P = .011). Group A had a higher prevalence of chondral defects of the trochlea (P = .016). No significant differences were identified in the prevalence and severity of meniscal lesions. At the final follow-up, all clinical scores were improved postoperatively but did not differ significantly between the groups. No significant differences were identified in side-to-side difference on Telos stress radiographs (group A, 6.3 ± 5.0 mm; group B, 5.6 ± 3.8 mm; P = .403) and graft failure rate (group A, 33.3%; group B, 30.6%; P = .358) at the final follow-up. CONCLUSIONS: The current study showed that the clinical outcomes of revision ACLRs in patients improved significantly in patients younger than 40 years and were comparable to those observed in patients older than 40 years at a minimum 2-year follow-up. LEVEL OF EVIDENCE: III.

Inside-Out Repair of the Meniscus in Concomitant Anterior Cruciate Ligament Reconstruction: Absorbable Versus Nonabsorbable Sutures.

PURPOSE: To compare the clinical and magnetic resonance imaging (MRI) outcomes of meniscal repair using absorbable versus nonabsorbable sutures in patients undergoing concomitant anterior cruciate ligament reconstruction. METHODS: Data of 142 patients who underwent meniscal repair with concomitant anterior cruciate ligament reconstruction using either absorbable or nonabsorbable sutures for longitudinal meniscal tear were retrospectively reviewed. Inside-out suture technique was used for all meniscal repairs. Weight bearing and flexion (>90°) were allowed after 6 weeks postoperatively. Clinical evaluations were assessed by the International Knee Documentation Committee subjective score, Lysholm score, and Tegner activity score preoperatively and at 2-year follow-up. MRI outcomes at 1-year follow-up were compared to identify the successful healing (complete or partial healing) rate and incidence of additional meniscal tears. Subgroup analysis was performed to evaluate the results of medial or lateral meniscus. RESULTS: Eighty patients underwent meniscal repair using absorbable sutures (mean age, 26.3 ± 11.9 years) and 62 patients with nonabsorbable sutures (mean age, 27.2 ± 10.0 years). There were no differences in zone and length of meniscal tears and stability tests between the groups. At a 2-year follow-up, all clinical scores had improved in both groups but did not differ significantly between the groups. Successful healing rate based on 1-year postoperative MRI was not significantly different between the absorbable and nonabsorbable sutures (93.7% vs 96.8%, P = .469). However, the absorbable sutures showed a lower additional tear incidence than the nonabsorbable sutures (2.5% vs 9.6%, P = .031). Subgroup analysis showed that the successful healing rate was not significantly different between the suture materials in both the medial and lateral menisci. CONCLUSIONS: The use of absorbable sutures leads to comparable healing rates to and lower incidence of additional tears than nonabsorbable sutures in patients undergoing meniscal repair with anterior cruciate ligament reconstruction. LEVEL OF EVIDENCE: Level III, retrospective comparative therapeutic trial.

Influence of Posterior Tibial Slope on Clinical Outcomes and Survivorship After Anterior Cruciate Ligament Reconstruction Using Hamstring Autografts: A Minimum of 10-Year Follow-Up.

PURPOSE: To investigate the influence of medial and lateral posterior tibial slope (PTS) on long-term clinical outcomes and survivorship after anterior cruciate ligament (ACL) reconstruction using hamstring autografts. METHODS: A total of 232 patients (mean age, 28.2 ± 8.9 years) who underwent primary ACL reconstruction from October 2002 to July 2007 were retrospectively reviewed. Patients with multiple ligament reconstruction, total meniscectomy, contralateral knee surgery before ACL reconstruction, open growth plate, and less than 10-year follow-up were excluded in the study. The medial and lateral PTS were measured from preoperative magnetic resonance imaging. Based on Li et al.'s previous study, the patients were divided into 2 groups according to their medial PTS (≤5.6° vs >5.6°) and lateral PTS (≤3.8° vs >3.8°), respectively. Clinical outcomes (clinical scores, stability tests and failure rate) were compared between the groups at the last follow-up. Furthermore, survival analysis was performed using the Kaplan-Meier method. RESULTS: All clinical scores (International Knee Documentation Committee subjective, Lysholm, and Tegner activity scores) and stability tests (physical examinations and side-to-side difference in Telos stress radiographs) were insignificantly different between the 2 groups classified based on medial or lateral PTS. However, the failure rate was significantly higher in patients with medial PTS >5.6° (16.1% vs 5.1%, P = .01) or lateral PTS >3.8° (14.5% vs 4.7%; P = .01). The odds ratios of graft failure due to increased medial and lateral PTS were 3.18 (95% confidence interval, 1.22-8.28; P = .02) and 3.43 (95% confidence interval, 1.29-9.09; P = .01), respectively. In addition, the 10-year survivorship was significantly lower in patients with medial PTS >5.6° (83.9% vs 94.9%, P = .01) or lateral PTS >3.8° (85.5% vs 96.0%; P = .01). CONCLUSIONS: Increased medial (>5.6°) and lateral (>3.8°) PTS were associated with higher failure rate and lower survivorship at a minimum of 10-year follow-up after primary ACL reconstruction using hamstring autografts. LEVEL OF EVIDENCE: Level III, retrospective comparative trial.

Re-revision anterior cruciate ligament reconstruction showed more laxity than revision anterior cruciate ligament reconstruction at a minimum 2-year follow-up.

PURPOSE: This study aimed to compare patient demographics, associated lesions (concurrent meniscal and chondral injuries), and clinical outcomes between revision and re-revision anterior cruciate ligament reconstructions. METHODS: Patients who underwent revision or re-revision anterior cruciate ligament reconstruction between 2008 and 2016 with a minimum 2-year follow-up were retrospectively evaluated. Detailed patient demographic data, radiographic preoperative tunnel diameters, posterior tibia slope, and concurrent meniscal and chondral lesion were reviewed. Clinical scores and laxity tests' results were compared between the groups at the last follow-up. RESULTS: Eighty-two patients (mean age, 33.8 ± 9.9 years; revision group, n = 62; re-revision group, n = 20) were included. The re-revision group showed a higher grade for preoperative arthritis (P < 0.001); more severe preoperative bone defects of the femoral (13.8 ± 2.6 vs 11.7 ± 2.7 mm, P = 0.004) and tibial tunnels (14.6 ± 2.4 vs 13.0 ± 2.3 mm, P = 0.010); and a higher prevalence of subtotal medial meniscectomy (P = 0.008) and chondral defects of the medial (P = 0.006) and lateral femoral condyles (P < 0.001), patella (P = 0.040), and trochlea (P = 0.036). At the final follow-up, the clinical scores did not differ significantly between the groups. However, the re-revision group showed more instability in the anterior drawer (P = 0.001), Lachman (P < 0.001), and pivot-shift (P < 0.001) tests, while a side-to-side difference was observed on the Telos stress radiographs (7.1 ± 4.7 vs 4.9 ± 3.7 mm, P = 0.038). CONCLUSION: These findings showed that the patients who underwent re-revision had poor prognostic factors as compared with those who underwent revision anterior cruciate ligament reconstruction. Although the clinical scores did not differ significantly between the groups, the re-revision group showed more laxity at the 2-year follow-up. LEVEL OF EVIDENCE: Cohort study; IV.

A two-portal technique using a flexible reamer system is a safe and effective method for transportal anterior cruciate ligament reconstruction.

INTRODUCTION: A flexible reamer system (FRS) for transportal anterior cruciate ligament reconstruction (ACLR) has been developed to overcome the technical challenges of a rigid reamer system. The purpose of this study was to investigate the safety and effectiveness of the two-portal technique using an FRS by evaluating femoral tunnel geometry. METHODS: This study included 30 patients (mean age 30 ± 12.1) who underwent transportal single-bundle ACLR. Operations were performed with the two-portal technique using an FRS. Three-dimensional computed tomography was performed for all patients 2 days after the operation. The femoral tunnel position, femoral graft bending angle, femoral tunnel length, and posterior wall breakage were evaluated. These radiologic outcomes were compared to previous literature-reported outcomes. RESULTS: The mean distances (measured as a percentage) from the posterior wall and the intercondylar notch roof to the femoral tunnel center were 29.6 ± 5.5% and 20.1 ± 6.7%, respectively. The femoral graft bending angle (108.4° ± 6.9°) was similar to that associated with the traditional transportal technique using a rigid reamer system, but it was less acute than that associated with the three-portal technique using an FRS. The femoral tunnel length (32.8 ± 4.5 mm) was also similar to the results of the traditional transportal technique using a rigid reamer system, but it was shorter than that of three-portal technique using an FRS. The prevalence of posterior wall breakage was as low as the reported outcomes of the outside-in technique (2 cases, 6.6%). CONCLUSIONS: The two-portal technique for transportal ACLR using an FRS can achieve comparable femoral graft bending angle and femoral tunnel length compared with the conventional three-portal technique using the rigid reamer system and had a low risk of posterior wall breakage. Therefore, the two-portal technique using the FRS can be considered a safe and effective method for transportal ACLR. LEVEL OF EVIDENCE: Retrospective case series; level of evidence, 4.

Is Lateral Posterior Tibial Slope Correlated With Clinical Outcomes of Lateral Meniscus Allograft Transplantation?

PURPOSE: To investigate (1) the correlation between lateral posterior tibial slope (PTS) and clinical outcomes of lateral meniscus allograft transplantation (MAT) and (2) the difference of lateral PTS between the extrusion and nonextrusion groups or between the failure and nonfailure groups in lateral MAT. METHODS: Between January 2001 and February 2016, we retrospectively evaluated 61 patients (mean age, 29.1 ± 12.2 years) who underwent postoperative magnetic resonance imaging (MRI) and were followed for a minimum of 2 years after primary lateral MAT. The lateral PTS and graft extrusion in the coronal and sagittal planes were assessed by using MRI performed at 1 year postoperatively. Clinical scores and graft failure were evaluated at the last follow-up visit. The correlation between lateral PTS and clinical outcomes (clinical scores, graft extrusion) was analyzed. Lateral PTS was compared between the extrusion and nonextrusion groups and between the failure and nonfailure groups. RESULTS: Mean lateral PTS on MRI was 6.6° ± 3.1° (range, 0.8° to 15.7°). A significant correlation was not identified between lateral PTS and clinical outcomes (clinical scores, graft extrusion in the coronal and sagittal planes). A significant difference in lateral PTS was not identified between the extrusion and nonextrusion groups in the coronal (6.2° ± 2.5° vs 7.0° ± 3.4°, P = .400) and sagittal (anterior horn, 6.5° ± 2.3° vs 6.7° ± 3.7°, P = .988; posterior horn, 6.8° ± 3.5° vs 6.5° ± 2.7°, P = .771) planes. Moreover, a significant difference was not identified between the failure and nonfailure groups (7.5° ± 3.3° vs 6.4° ± 3.0°, P = .388). CONCLUSIONS: A significant correlation between lateral PTS and clinical or radiologic outcomes of lateral MAT was not identified. LEVEL OF EVIDENCE: Level IV, therapeutic case series with subgroup analysis.

Clinical outcomes and survival rate of autologous chondrocyte implantation with and without concomitant meniscus allograft transplantation: 10- to 15-year follow-up study.

PURPOSE: The purpose of this study was to compare the clinical outcomes and survival rate of autologous chondrocyte implantation (ACI) with or without concomitant meniscus allograft transplantation (MAT). METHODS: Patients who underwent ACI of the medial or lateral femoral condyle with or without concomitant MAT were retrospectively reviewed. There were 14 patients (mean age, 31.2 ± 9.9 years) who underwent isolated ACI and 19 patients who underwent ACI with concomitant MAT (mean age, 34.8 ± 8.4 years). The International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity score, and 10- to 15-year survival rate were compared between groups. RESULTS: All clinical scores showed significant improvement postoperatively in both groups. At final follow-up, the IKDC subjective score was superior in isolated ACI (75.8 ± 18.4) compared to ACI with MAT (61.0 ± 16.6, p = 0.024). The Lysholm score was also higher in isolated ACI (77.5 ± 19.1) than ACI with MAT (62.5 ± 18.1, p = 0.029). The Tegner activity score did not differ between treatments (isolated ACI, 5.3 ± 1.1; ACI with MAT, 4.5 ± 1.3; p = 0.072). The 15-year survival rate for isolated ACI was higher than that of ACI with concomitant MAT (69.6% vs 50.2%), but this difference was not statistically significant (p = 0.19). CONCLUSIONS: ACI with concomitant MAT did not restore clinical outcomes as much as isolated ACI. There was a trend for the long-term survival rate to be greater in isolated ACI than ACI with MAT. These results should be considered in planning for the treatment of focal chondral defect with meniscus deficiency. LEVEL OF STUDY: Retrospective comparative trial; level of evidence, 3.

The Influence of Segond Fracture on Outcomes After Anterior Cruciate Ligament Reconstruction.

PURPOSE: To determine the prevalence of Segond fractures using computed tomography (CT) and to investigate the effects of Segond fractures on the outcomes of primary anterior cruciate ligament (ACL) reconstruction for isolated ACL injuries. METHODS: Between January 2010 and July 2015, we retrospectively evaluated 383 patients who underwent primary ACL reconstruction, who underwent CT scans immediately after surgery, and who were available at 2 years of follow-up. The absence or presence of a Segond fracture was confirmed using CT. The following parameters were evaluated in all patients at the 2-year follow-up visit: clinical scores (International Knee Documentation Committee subjective score, Lysholm score, and Tegner activity score) and knee joint stability (anterior drawer test, Lachman test, pivot-shift test, and side-to-side difference in anterior tibial translation on Telos stress radiographs). RESULTS: Among 383 patients with primary ACL tears, a Segond fracture was confirmed in 8.9% (n = 34) using 3-dimensional CT. We placed 349 patients into the group with ACL tears without Segond fractures (group A) and the other 34 into the group with ACL tears with Segond fractures (group B). Between the 2 groups, there were no significant differences in the postoperative International Knee Documentation Committee subjective score (P = .97), Lysholm score (P = .17), or Tegner activity score (P = .95). No significant differences in the anterior drawer test (P = .28), Lachman test (P = .45), pivot-shift test (P = .14), and side-to-side difference in anterior tibial translation on Telos stress radiographs (P = .93) between the 2 groups were found preoperatively and postoperatively. CONCLUSIONS: The presence of a Segond fracture did not affect knee joint stability in patients with ACL tears. Moreover, the 2 groups did not show significant differences in clinical scores or knee joint stability after undergoing ACL reconstruction. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Multiple looping technique for tibial fixation in posterior cruciate ligament reconstruction using free tendon Achilles allograft.

PURPOSE: This study was conducted to evaluate case series outcomes of a new tibial fixation technique using a free tendon graft during posterior cruciate ligament (PCL) reconstruction which is less affected by tibial metaphysis bone density. METHODS: Thirty-two subjects underwent single-bundle PCL reconstruction using a free tendon Achilles allograft. The graft was looped to be double stranded. The free ends of the graft were fixed to the femoral side using suture washer, and the looped end was fixed to the tibial side using the multiple looping technique. Range of motion of the knee and side-to-side difference were assessed at the last follow-up. The Lysholm Knee score was evaluated preoperatively and at the last follow-up. The Tegner Activity Scale score was evaluated before injury and at the last follow-up. RESULTS: Twenty-eight subjects were followed up for at least 18 months. Mean follow-up was 27.7 ± 4.8 months. All subjects showed normal range of motion at the last follow-up. The mean side-to-side difference was 10.4 ± 2.8 mm preoperatively and 2.3 ± 1.8 mm at the last follow-up (p < 0.001). The mean Lysholm Knee score was 58 ± 9 preoperatively and 91 ± 5 at the last follow-up (p < 0.001). The median Tegner Activity Scale score was 7 (range 5-9) before injury and 6 (range 4-8) at the last follow-up (p = 0.001). CONCLUSIONS: The multiple looping technique for tibial fixation resulted in satisfactory outcomes from single-bundle PCL reconstruction without any significant complications. LEVEL OF EVIDENCE: Therapeutic case series, Level IV.