Stuart, Michael J.

Background: Previous studies have demonstrated that medial meniscus posterior root tear (MMPRT) repair is superior to debridement in terms of patient-reported outcomes, rates of conversion to total knee arthroplasty (TKA), and long-term costs. Despite the known poor midterm outcomes, there is a paucity of long-term results of partial meniscectomy for degenerative MMPRTs. Purpose: To 1) evaluate long-term patient-reported and radiographic outcomes of patients who underwent partial medial meniscectomy (PMM) for MMPRTs, and 2) determine the rate of and risk factors for conversion to total knee TKA. Study Design: Case series; Level of evidence, 4. Methods: A previously identified cohort of 26 patients treated with partial meniscectomy for isolated MMPRTs between 2005 and 2013 was prospectively followed for long-term outcomes at a minimum 10-year follow-up. Patients were evaluated for International Knee Documentation Committee (IKDC) outcome score, reoperation, and conversion to TKA. Failure was defined as conversion to arthroplasty or a severely abnormal IKDC subjective score <75.4. Results: This study included 26 patients (10 men, 16 women; mean age, 54 ± 8.7 years [range, 38-71 years] at diagnosis; body mass index, 32.9 ± 5.5) who were followed for a mean of 14.0 ± 3.6 years (range, 10.1-19.6 years). At the final follow-up, 1 patient was deceased and 18 (72%) of the remaining 25 patients had progressed to TKA, with 1 (4%) patient undergoing repeat meniscectomy. The 6 (24%) patients who had not progressed to TKA or revision surgery reported a mean IKDC score of 57 ± 23. Nineteen patients underwent subsequent surgery and 5 demonstrated severely abnormal IKDC scores resulting in a clinical failure rate of 96% (24 of the 25 living patients) at a mean 14-year follow-up. Conclusion: PMM for medial meniscus posterior horn root tears demonstrated 72% progression to TKA and 96% failure according to subjective clinical outcomes at a minimum 10-year follow-up.

Objectives: Medial meniscus posterior root tears (MMPRTs) render the meniscus essentially non-functional, resulting in increased peak contact pressures, reduced forced dissipation, and increased risk of early osteoarthritis. Transtibial root repair has shown promise at restoring meniscus function and improving clinical outcomes; however, a paucity of literature exists evaluating the prognostic clinical and radiographic factors for poor outcomes following isolated meniscus root repair. The purpose of this study was to 1) describe the patient reported clinical outcomes after isolated MMPRT repair at minimum 2-year follow-up, 2) determine the retear and conversion to arthroplasty rates, and 3) identify prognostic factors for clinical outcomes and International Knee Documentation Committee (IKDC) Patient Acceptable Symptom State (PASS) achievement. Methods: Isolated MMPRT repairs from 2010-2020 at three institutions in Rochester, MN; Jacksonville, FL; and Phoenix, AZ were followed prospectively for postoperative Tegner Activity Scale, Visual Analog Scale (VAS) for pain, IKDC, Forgotten Joint Score (FJS), subjective improvement and knee preference, and subsequent surgeries at minimum 2-year follow up. PASS for IKDC was set at 69. Demographics, injury characteristics, and surgical details were collected. Results: Eighty-four patients were included in this study (age: 49.7 ± 11.0 years [range: 13-76]; sex: 75.0% female; BMI: 31.6 ± 6.9 kg/m 2 [MH1] ). Forty-five patients (53.6%) had BMI >30 kg/m 2 , and 14 patients (16.7%) reported a history of active smoking (Table 1). Mean medial compartment Outerbridge grade was 2.0 ± 1.1, with 73.8% of patients having grade ≥2 changes. Mean preinjury Tegner score, preoperative VAS at rest, and preoperative VAS with use were 4.6 ± 2.4, 3.6 ± 2.7, and 6.5 ± 2.5, respectively. At final follow-up (mean 3.9 ± 2.0 years), mean Tegner score was 4.3 ± 1.8, mean VAS at rest was 1.2 ± 2.0, and mean VAS with use was 2.3 ± 2.2. There was no significant difference in preinjury vs. postoperative Tegner scores (p = 0.208), and preinjury Tegner was significantly positively correlated with postoperative Tegner (p < 0.001). Significant (p < 0.001) postoperative improvements in both VAS at rest and with use were observed. Mean postoperative IKDC score was 73.3 ± 17.0, and mean FJS was 59.6 ± 27.9 at final follow-up. When asked to rate their knee at final follow-up compared to before surgery on a scale from 0-5 (0 = “significantly worse”, 1 = “mildly worse”, 3 = “unchanged”, 4 = “mildly improved”, 5 = “significantly improved”), the mean score 4.6 ± 0.8. Forty-one patients (74.5%) reported significant improvement, 8 (14.5%) reported mild improvement, 3 (5.5%) reported no change, and 3 (5.5%) reported mild worsening. No patients reported significant worsening. When asked which knee they preferred, 13 patients (26.0%) reported preferring their operated knee, compared to 18 (36.0%) who preferred their nonoperated knee. The remaining 19 patients (38.0%) had no preference for one knee over the other. A summary of all patient reported outcomes is reported in Table 2. At the time of final follow-up, 16 (19.0%) of patients had reached a clinical endpoint. Twenty-nine patients (34.5%) underwent postoperative MRIs at an average of 1.5 ± 1.7 years (range: 0.3-5.9 years) after surgery[MH1] . Twelve of the MRIs (41.4%) were ordered for evaluation of continued pain, while 7 (24.1%) were ordered for new pain or injury, and 10 (34.5%) were ordered for research purposes. Five patients (6.0%) had MRI-confirmed retears of the MMPRT repair at an average of 1.1 ± 1.3 years (range: 0.3-3.4) after surgery[HMMP2] , one of which was in an asymptomatic patient who received a follow-up MRI for research purposes. No patients underwent revision MMPRT repair surgery, and 7 patients (8.3%) progressed to arthroplasty (6 TKA, 1 UKA) at an average of 3.4 ± 4.3 years (range 0.6-12.6), one of whom also sustained a root retear. Therefore, the surgical failure was noted in 11 patients, corresponding to a surgical failure rate of 13.1% in this cohort. Of note, three of the five patients with MRI-confirmed retears had not received any further surgical intervention[MH3] [BA(M4] at the time of final follow-up 2.7, 3.8, and 8.5 years after surgery. Additionally, there were six non-MMPRT revision, non-arthroplasty subsequent surgeries in five patients, and there were three patients (3.6%) who sustained new medial meniscus tears 2.8-, 3.6-, and 5.9-years postoperatively, respectively. A concise summary of clinical endpoints can be found in Table 3 and Table 4. Significantly more females experienced surgical failures than males (17.5% vs. 0%, p = 0.040), and significantly more patients with medial compartment Outerbridge grades ≥2 experienced surgical failure than those with grades <2 (17.7% vs. 0%, p = 0.034). Additionally, patients who failed did have significantly higher mean KL grades than those who did not (1.4 ± 0.9 vs. 0.7 ± 0.7, p = 0.012). There were no other significant differences in the demographic or pathologic characteristics of patients who experienced surgical failure and those who did not. Of note, 37% of patients failed to achieve IKDC PASS, with smoking status associated with a 15-point reduction in IKDC (p=0.010) Conclusions: Patients undergoing transtibial root repair demonstrate restoration of pre-injury activity levels, significant clinical improvements in pain and function, and low surgical failure rates at minimum 2-year follow-up, with 89% of patients reporting subjective improvement after surgery. However, only 63% of patients were able to achieve PASS thresholds, suggesting that while effective, additional research on root repair technical and clinical optimization is warranted.

Purpose To report the rate of anterior cruciate ligament (ACL) graft failure by physis status (open, closing, closed) and to analyze which factors were associated with higher risk of ACL graft failure. Methods Patients younger than 18 years who underwent transphyseal ACL reconstruction (ACLR) between 2000 and 2018 at a single institution were reviewed at minimum 2 years after ACLR. Patient records were reviewed for anthropometrics, surgical techniques, and ACL graft failure. Patients were subsequently stratified based on physis status (open, closing, closed) and analyzed. Results A total of 272 patients (mean age of 15.4 ± 1.3 years) were assessed. The transtibial technique was used in 63.6% of cases. A hamstring autograft was used exclusively in the open physis group. A patellar tendon autograft was used in 65.9% of patients with a closing physis and 80.9% of patients with a closed physis. The overall graft failure rate was 13.2%, with a contralateral ACL injury rate of 11.0%. Kaplan‐Maier analysis by physis status showed different injury free from ACL reinjury ( P < .001). An open physis was associated with increased risk of ACL reinjury (hazard ratio, 5.2; P < .001) when compared to a closed physis. A closing physis presented a higher hazard ratio but was not statistically significant (hazard ratio, 2.6; P = .08). Hamstring graft type ( P = .03) and lower graft diameter ( P = .04) were significantly related to higher ACL reinjury after adjusting for physis status. Conclusions Transphyseal ACLR is a safe procedure in pediatric patients. The rate of reinjury was 13.2%. This rate decreases with skeletal maturity, use of patellar tendon autograft, and a larger graft diameter. Level of Evidence Level III, retrospective cohort study.

Background: Patients with isolated anterior cruciate ligament (ACL) reconstruction have demonstrated an increased risk of ACL graft failure and lower patient-reported outcome (PRO) scores when increased posterior tibial slope (PTS) is present. However, there is a paucity of literature evaluating the effect of PTS on outcomes after combined bicruciate multiligamentous knee reconstruction. Purpose: To determine whether differences exist for graft failure rates or PRO scores based on PTS after combined bicruciate multiligamentous knee reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: All patients who underwent combined ACL and posterior cruciate ligament (PCL) reconstruction between 2000 and 2020 at our institution were identified. Exclusion criteria were age <18 years, knee dislocation grade 5 injuries, concomitant osteotomy procedures, and <2 years of clinical follow-up. Demographic and outcomes data were collected from our prospectively gathered multiligamentous knee injury database. Lysholm and International Knee Documentation Committee (IKDC) scores were analyzed in relation to PTS. Outcomes were compared for patients with a PTS above and below the mean for the total cohort, PTS >12° versus <12°, positive versus negative Lachman test at follow-up, and positive versus negative posterior drawer test at follow-up. Results: A total of 98 knees in 98 patients were included in the study, with a mean clinical follow-up of 5.1 years (median, 4.6 years; range, 2-16 years). The mean PTS was 8.7° (range, 0.4°-16.9°). Linear regression analysis showed no significant correlation between PTS and IKDC or Lysholm scores. Patients with a PTS above the mean of 8.7° trended toward lower IKDC ( P = .08) and Lysholm ( P = .06) scores. Four patients experienced ACL graft failure and 5 patients experienced PCL graft failure. There were no differences in graft failure rates or PRO scores for patients with a PTS >12°. Patients with a positive Lachman test trended toward higher PTS (9.6° vs 8.5°, P = .15). Conclusion: In this series of bicruciate multiligamentous knee reconstructions at midterm follow-up, no differences in graft failures, complications, reoperations, revisions, or PRO scores based on PTS were identified. Patients with a positive Lachman test were found to have a slightly higher PTS, although this did not reach statistical significance.

Background: Increased posterior tibial slope (PTS) leads to a relative anterior translation of the tibia on the femur. This is thought to decrease the stress on posterior cruciate ligament (PCL) reconstruction (PCLR) grafts. Purpose/Hypothesis: The purpose of this study was to analyze the effect of PTS on knee laxity, graft failure, and patient-reported outcome (PRO) scores after PCLR without concomitant anterior cruciate ligament reconstruction (ACLR). It was hypothesized that patients with higher PTS would have less knee laxity, fewer graft failures, and better PROs compared with patients with lower PTS. Study Design: Case-control study; Level of evidence, 3. Methods: All patients who underwent PCLR between 2001 and 2020 at a single institution were identified. Patients were excluded if they underwent concomitant or prior ACLR or proximal tibial osteotomy, were younger than 18 years, had <2 years of in-person clinical follow-up, and did not have documented PRO scores (Lysholm score and International Knee Documentation Committee [IKDC] score). Data were collected retrospectively from a prospectively gathered database. PTS measurements were recorded from perioperative lateral knee radiographs. A linear regression model was created to analyze PTS in relation to PRO scores. Patients with a grade 1 (1-5 mm) or higher posterior drawer were compared with those who had a negative posterior drawer. Results: A total of 37 knees met inclusion criterion; the mean age was 30.7 years at the time of surgery. The mean clinical follow-up was 5.8 years. No significant correlation was found between either the Lysholm score or the IKDC score and the PTS. Twelve knees (32.4%) had a positive posterior drawer at final follow-up. The mean PTS in knees with a positive posterior drawer was 6.2°, whereas that for knees with a negative posterior drawer was 8.3° ( P = .08). No significant differences in PRO scores were identified for knees with versus knees without a positive posterior drawer. No documented graft failures or revisions were found. Conclusion: No significant differences were found in PROs or graft failure rates based on PTS at a mean of 5.8 years after PCLR. Increased tibial slope trended toward being protective against a positive posterior drawer, although this did not reach statistical significance.

Background: Osteochondral allograft transplantation (OCAT) is an accepted knee joint–preserving treatment strategy for focal osteochondral lesions that is often conducted in combination with meniscal allograft transplantation (MAT). Despite its frequent and simultaneous utilization, there remains a lack in the literature reporting on outcomes and failure rates after concomitant procedures. Purpose: To determine (1) the midterm clinical success rate after OCAT+MAT in comparison with a matched-pair cohort undergoing isolated OCAT, (2) whether patient-specific and procedural variables influence the risk of failure, and (3) patient-reported outcome measures over time. Study Design: Cohort study; Level of evidence, 3. Methods: A single-center matched-pair cohort study was conducted investigating outcomes in patients who underwent OCAT of the medial or lateral femoral condyle with and without MAT between 2004 and 2020. Patients were matched 1:1 by age (±5 years), sex (male or female), body mass index (±5), and grouped Kellgren and Lawrence grade (grades 0-1 or 2-4). The minimum follow-up time was 2 years. Radiographic variables (International Cartilage Regeneration & Joint Preservation Society [ICRS] grade and Kellgren and Lawrence grade) were assessed preoperatively and at follow-up. Subjective patient-reported outcome measures (Lysholm score, Knee injury and Osteoarthritis Outcome Score [KOOS] including subscores, International Knee Documentation Committee [IKDC] score, and visual analog scale score) were collected preoperatively and at follow-up. Clinical failure was defined as revision surgery for graft failure or conversion to total knee arthroplasty. Patient-reported, clinical, and radiographic outcomes were compared between groups. Results: In total, 66 patients (33 treated with isolated OCAT, 33 treated with OCAT+MAT; 57.6% male) with a mean age of 26.3 years (range, 18-62 years) were followed for a mean of 5.6 years (minimum, 2 years; range, 24-218 months). The 2 cohorts showed no difference in Kellgren and Lawrence grade postoperatively ( P = .59). There was a significantly higher ICRS grade detected at follow-up in the OCAT+MAT group (2.81 ± 1.10) compared with the OCAT group (2.04 ± 0.96) ( P < .05). There were no statistically significant differences between the groups regarding reoperation rate (OCAT: n = 6; OCAT+MAT: n = 13; P = .116), time to reoperation (OCAT: 46.67 ± 47.27 months vs OCAT+MAT: 28.08 ± 30.16 months; P = .061), and failure rate (OCAT: n = 4 [12.1%] vs OCAT+MAT: n = 5 [15.2%]; P = .66). In the OCAT+MAT group, an increase of tibial slope by 1° conferred a 1.65-fold increase in the hazard for failure over decreased slope (hazard ratio, 1.65; 95% CI, 1.10-2.50; P < .05). The overall survival rate was 86% at a mean follow-up of 5.6 years. Patient-reported outcome scores were significantly improved at the final follow-up compared with preoperative status. No significant differences were seen between groups with respect to subjective IKDC, Lysholm, Tegner, and KOOS results, except for the KOOS Symptoms subscale score, which was significantly higher in the OCAT+MAT group than in the OCAT group (mean difference, 14.6; P < .05) and did exceed the minimal clinically important difference threshold of 10.7. Conclusion: Midterm results after isolated OCAT and OCAT+MAT show high rates of healing and sustainable subjective improvement of knee function and quality of life. However, it should be noted that the difference in reoperation rate and time to reoperation between the groups is arguably clinically important and that lack of statistical significance may be because of low power. These results imply that isolated OCAT is an efficient joint-preserving treatment that can be combined with MAT in well-selected patients with meniscal insufficiency without negative influence on global clinical outcomes.

Case: A 29-year-old man sustained a bilateral acute patellar tendon rupture (PTR) while jumping on a trampoline. He was initially treated with bilateral transosseous patellar tendon repairs. Bilateral rerupture occurred during a fall 10 weeks after. He subsequently underwent staged bilateral patellar tendon reconstructions using an Achilles tendon allograft. At 3-year follow-up, he has maintained full range of motion and leg strength without rerupture or other complications. Conclusion: The use of Achilles tendon allograft in the presence of inadequate and poor-quality tendon tissue for reconstruction of the patellar tendon in the revision setting is a viable and effective treatment option.

Background: Multiligamentous knee injuries (MLKIs) are devastating injuries with concomitant injuries that complicate treatment and recovery. Short-term studies have shown satisfactory patient outcomes after surgical treatment; however, evaluations of long-term outcomes remain scarce. Purpose: To evaluate long-term outcomes after surgically reconstructed MLKIs and further investigate the relationship between patient age on clinical outcomes. Study Design: Case series; Level of evidence, 4. Methods: A total of 55 knees (age, 36 ± 11 years; 24% female subjects) who underwent surgical reconstruction for MLKI between 1992 and 2013 met the study inclusion criteria and were evaluated with postoperative patient-reported outcomes (PROs) including International Knee Documentation Committee (IKDC) score, Lysholm score, visual analog scale (VAS) for pain, Forgotten Joint Score, subjective improvement ratings and surgery satisfaction, and Tegner activity scores. PRO scores, revision, and conversion to arthroplasty were analyzed using descriptive statistics, linear regression, Wilcoxon rank-sum, and Fisher exact tests. Results: At final follow-up (mean, 15 ± 5 years; range, 10-31 years), 67% of the cohort reported subjective improvement in their knee, and 82% reported satisfaction with their surgery. Compared with preoperative scores, there were significant improvements in postoperative VAS pain at rest in the full cohort, age ≤30-year cohort, and age >30-year cohort (4 ± 1 vs 2 ± 2; 4 ± 1 vs 2 ± 3; 4 ± 1 vs 1 ± 2, respectively; P≤ .029 for all) but significant reductions in Tegner scores (6 ± 3 vs 4 ± 2; 7 ± 2 vs 5 ± 2; 5 ± 2 vs 3 ± 1; P≤ .003 for all). Younger patients had higher postoperative Tegner scores than older patients (5 ± 2 vs 3 ± 1, respectively; P = .003), but no other differences in PROs were observed based on age. At a mean 15-year follow-up, 3.6% of the cohort underwent revision ligament surgery and 10.9% required arthroplasty. Conclusion: The majority of the cohort reported modest subjective improvement and were satisfied with their surgery. Gradual but expected age-related decreases in Tegner scores were observed, and some patients demonstrated continued symptomatic and functional limitations, but mean PRO scores remained satisfactory. Revision surgery and conversion to arthroplasty were not commonly required.

Background: The medial patellofemoral ligament (MPFL) is the primary soft tissue restraint to lateral patellar translation and is often disrupted by lateral patellar dislocation. Surgical management for recurrent patellar instability focuses on restoring the MPFL function with repair or reconstruction techniques. Recent studies have favored reconstruction over repair; however, long-term comparative studies are limited. Purpose: To compare long-term clinical outcomes, complications, and recurrence rates of isolated MPFL reconstruction and MPFL repair for recurrent lateral patellar instability. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 55 patients (n = 58 knees) with recurrent lateral patellar instability were treated between 2005 and 2012 with either MPFL repair or MPFL reconstruction. The exclusion criteria were previous or concomitant tibial tubercle osteotomy or trochleoplasty and follow-up of <8 years. Pre- and postoperative descriptive, surgical, imaging, and clinical data were recorded for each patient. Results: MPFL repair was performed on 26 patients (n = 29 knees; 14 women, 15 men), with a mean age of 18.4 years. MPFL reconstruction was performed on 29 patients (n = 29 knees; 18 women, 11 men), with a mean age of 18.2 years. At a mean follow-up of 12 years (range, 8.3-18.9 years), the reconstruction group had a significantly lower rate of recurrent dislocation compared with the repair group (14% vs 41%; P = .019). There were no differences in the number of preoperative dislocations or tibial tubercle–trochlear groove distance. The reconstruction group had significantly more time from initial injury to surgery compared with the repair group (median, 1460 days vs 627 days; P = .007). There were no differences in postoperative Tegner, Lysholm, or Kujala scores at the final follow-up. In addition, no statistically significant differences were detected in return to sport (RTS) rates (repair [81%] vs reconstruction [75%]; P = .610) or reoperation rates for recurrent instability (repair [21%] vs reconstruction [7%]; P = .13). Conclusion: MPFL repair resulted in a nearly 3-fold higher rate of recurrent patellar dislocation (41% vs 14%) at the long-term follow-up compared with MPFL reconstruction. Given this disparate rate, the authors recommend MPFL reconstruction over repair because of the lower failure rate and similar, if not superior, clinical outcomes and RTS.

Background: Meniscal allograft transplantation (MAT) is an accepted and effective treatment option in the context of unsalvageable menisci, particularly in young and active patients. It has been shown to reduce pain and improve knee function in previously symptomatic patients. However, there is still limited knowledge about the long-term survival rates of allografts, the durability of clinical results, and the influence of patient-specific parameters, such as leg alignment, tibial slope, and preoperative International Cartilage Regeneration & Joint Preservation Society (ICRS) grade. Purpose: To determine (1) the long-term clinical success rate after MAT with bony fixation in a large, single-center cohort of consecutive patients, and (2) if patient-specific and procedural variables influence the clinical, anatomic, and subjective outcomes and risk of failure. Study Design: Case-control study; Level of evidence, 3. Methods: Data on 185 consecutive knees undergoing MAT in a single institution were prospectively collected and screened for inclusion in this study. The minimum follow-up time was 2 years. Radiographic variables (ICRS grade and Kellgren-Lawrence grade) were assessed preoperatively and at follow-up. Subjective patient-reported outcome measures (PROMs) (Lysholm score, Knee injury and Osteoarthritis Outcome Score [KOOS] including subscores, International Knee Documentation Committee [IKDC] score, and visual analog scale [VAS] score) were collected preoperatively and at follow-up. Clinical failure was defined as revision surgery due to graft failure or conversion to total knee arthroplasty. Anatomic failure was considered a tear covering >20% of the allograft, any peripheral tear, and unstable peripheral fixation leading to dislocation of the graft. Subjective failure was defined as Lysholm score ≤65. Preoperative tibial slope and leg alignment were assessed. Survival analyses were performed using the Kaplan-Meier estimate. Univariate and multivariate analyses were performed to determine risk factors for clinical and anatomic failure. Results: A total of 157 knees met inclusion criteria. After a mean follow-up time of 7 ± 3.5 years, 127 (80.9%) knees were free of clinical, anatomic, and subjective failure. Fourteen (8.9%) knees experienced clinical failure, 26 (16.6%) knees were identified as having experienced anatomic failure, and 13 (8.3%) patients experienced subjective failure with a reported Lysholm score of ≤65 at a mean follow-up of 7 years. Concurrent osteochondral allograft transplantation was identified as a predictor of both clinical (hazard ratio [HR], 4.55; 95% CI, 1.46-14.17; P = .009) and anatomic (HR, 3.05; 95% CI, 1.34-6.92; P = .008) failure. Cartilage damage of ICRS grade 3 or 4 of the index compartment conveyed an increased risk for clinical (HR, 3.41; 95% CI, 1.05-11.01; P = .04) and anatomic (HR, 3.04; 95% CI, 1.31-7.11; P = .01) failure. High-grade cartilage damage preoperatively (HR, 10.67; 95% CI, 1.037-109.768; P = .046), patient age >25 years (HR, 5.44; 95% CI, 0.120-246.070; P = .384), and a body mass index >30 (HR, 2.24; 95% CI, 0.748-6.705; P = .149) were associated with subjective failure. PROMs including KOOS and IKDC were significantly improved at final follow-up compared with preoperative scores across all measurements ( P < .005). Conclusion: MAT showed good to excellent clinical results at a mean follow-up of 7 years. Low ICRS lesion grade was associated with a higher clinical and anatomic survival rate. Patients with concurrent OCA transplantation are at a higher risk of clinical and anatomic failure, but still report significantly improved PROMs. These results suggest that MAT has a lasting beneficial effect both in isolation and in complex cases with ≥1 concurrent procedures.