Surgical treatment of distal hamstring tendon injuries yield a higher return-to-sports rate: A systematic review.

PURPOSE: The purpose of this study is to compare the patient-reported outcomes and return to sports of the conservative and surgical treatment of distal hamstring tendon injuries. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, two reviewers searched PubMed, Scopus and Virtual Health Library databases in January 2023. Clinical studies evaluating conservative or surgical management outcomes of distal hamstring tendon injuries were considered eligible for this systematic review if predefined criteria were fulfilled: (1) published in English or Spanish; (2) evaluated any of the following: patient-reported outcomes, return-to-sports rate (RTS-R) or return-to-sports time (RTS-T). Data were presented in tables using absolute values from individual studies and derived pooled percentages. RESULTS: Eighteen studies were included for 67 patients and 68 distal hamstring tendon injuries. Initially, 39 patients (58.2%) underwent surgical treatment, whereas 28 (41.8%) were treated conservatively. Among conservative treatment patients, 15 failed and had to be operated on (53.6%), all with distal semitendinosus tendon injuries. Anchor fixation was the technique of choice in 20 lesions (36.4%), tenodesis in 16 (29.1%), tenectomy in 14 (25.5%) and sutures were preferred in five (9%). Thirteen out of 28 patients (46.4%) undergoing initial conservative treatment returned to sports at a mean of 3.6 months (range 1 week to 12 months), in contrast to surgical treatment, in which 36 out of 39 patients (92.3%) returned at a mean of 4.2 months (range 6 weeks to 12 months). Additionally, 14 of 15 patients (93.3%) converted to surgical treatment after failed conservative treatment returned to sports at a mean of 7.6 months after injury. CONCLUSION: Initial surgical treatment of distal hamstring tendon injuries yields a high RTS-R (92.3%) at a mean of 4.2 months. Furthermore, 15 out of 28 patients (53.6%) initially treated conservatively had to be operated on, delaying the RTS-T (mean 7.6 months after injury) without affecting their RTS-R. LEVEL OF EVIDENCE: IV.

Isolated meniscus allograft transplantation with soft-tissue technique effectively reduces knee laxity in the presence of previous meniscectomy: In-vivo navigation of 18 consecutive cases.

OBJECTIVES: Although meniscal allograft transplantation (MAT) is a well-established procedure with satisfactory clinical results, limited in vivo kinematic information exists on the effect of medial and lateral MAT performed in the clinical setting. The purpose of the present study was to evaluate the biomechanical effect of arthroscopic isolated medial and lateral MAT with a soft-tissue fixation on pre- and post-operative knee laxity using a surgical navigation system. METHODS: 18 consecutive patients undergoing MAT (8 medial, 10 lateral) were enrolled. A surgical navigation system was used to quantify the anterior-posterior displacement at 30 and 90 degrees of knee flexion (AP30 and AP90), the varus-valgus rotation at 0 and 30 degrees of knee flexion (VV0 and VV30) and the dynamic laxity on the pivot-shift test (PS), which was determined through the anterior displacement of the lateral tibial compartment (APlat) and posterior acceleration of the lateral tibial compartment during tibial reduction (ACC). Data from laxity before and after MAT were compared through paired t-test (p â€‹< â€‹0.05). RESULTS: After medial MAT, there was a significant decrease in tibial translation of 3.1 â€‹mm (31%; p â€‹= â€‹0.001) for AP30 and 2.3 â€‹mm (27%; p â€‹= â€‹0.020) for AP90, a significant difference of 2.5° (50%; p â€‹= â€‹0.002) for VV0 and 1.7° (27%; p â€‹= â€‹0.012) for VV30. However, medial MAT did not determine any reduction in the PS kinematic data. Lateral MAT determined a significant decrease in the tibial translation of 2.5 â€‹mm (38%; p â€‹< â€‹0.001) for AP30 and 1.9 â€‹mm (34%; p â€‹= â€‹0.004) for AP90 as well as a significant difference of 3.4° (59%; p â€‹< â€‹0.001) for VV0 and of 1.7° (23%; p â€‹= â€‹0.011) for VV30. There was also a significant reduction of the PS of 4.4 â€‹mm (22%; p â€‹= â€‹0.028) for APlat and 384.8 â€‹mm/s2 (51%; p â€‹= â€‹0.005) for ACC. CONCLUSION: MAT with soft-tissue fixation results in a significant laxity reduction in an in-vivo setting. Medial MAT improved knee kinematics by determining a significant reduction with particular emphasis on AP translation and VV manoeuvre. Conversely, Lateral MAT determined a massive reduction of the PS and a mild decrease of the AP translation and VV manoeuvre. STUDY DESIGN: Controlled laboratory study.

Short-term outcomes of anterior cruciate ligament reconstruction with or without lateral tenodesis or anterolateral ligament reconstruction: a retrospective cohort.

PURPOSE: This study aimed to compare the short-term outcomes of ACL reconstruction (ACLR) alone, ACLR with lateral tenodesis, and ACL and ALL reconstruction. METHODS: A retrospective cohort of prospectively collected data on all ACL procedures was performed at Aspetar Specialized Orthopaedic and Sports Medicine Hospital between January 2020 and January 2021. Patients were treated with ACLR alone, ACLR with lateral tenodesis, or ACLR with ALL reconstruction. The primary outcome was the subjective International Knee Documentation Committee (sIKDC) score. The secondary outcomes were the ACL Return to Sport after Injury (ACL-RSI) scores, pivot shift grade, subjective knee stability, and subjective pain on activity. RESULTS: A total of 100 cases were included. The most common technique was ACLR with lateral tenodesis (42%), followed by ACLR alone (38%) and ACL with ALL reconstruction (20%). The mean age was 28.15 years (15-60), and 94% of the patients were males. Meniscal procedures were more frequent in the ACLR alone group (65.8%). There was no association between subjective stability, sIKDC, ACL-RSI, and pivot shift grade and the three ACLR techniques while adjusting for age, sex, and concomitant meniscus procedures at six weeks, 12 weeks, six months, and nine months. However, there was a significant decrease in postoperative flexion in the ACL and ALL reconstruction group by a mean of 22° (95% CI - 40.7 - 3.4; P = 0.02) at 6 weeks compared to ACLR alone, which was not evident on later follow-ups. CONCLUSION: ACLR with/without lateral augmentation procedures yields similar subjective IKDC, ACL-RSI, pivot shift grade, and subjective knee instability at short-term follow-up. Therefore, lateral extra-articular augmentation procedures are safe to be performed.

Good stability and mid-term subjective outcomes after repeated anterior cruciate ligament (ACL) revision surgery using allografts.

PURPOSE: To evaluate the mid-term clinical outcomes of a cohort of patients who underwent multiple ACL revision reconstructions. The hypothesis was that patients with pre-existing meniscal deficiency conditions, malalignment and cartilage degeneration would have obtained lower results. METHODS: All cases of multiple ACL revisions performed with allograft tissue at one single sport-medicine institution were extracted and patients with a minimum 2 years of follow-up were included. WOMAC, Lhysolm, IKDC, and Tegner activity level before the injury and at last follow-up was collected and laxity evaluated with KT-1000 arthrometer and KiRA triaxial accelerometer. RESULTS: From a cohort of 241 ACL revisions, 28 patients (12%) with Repeated ACL Revision reconstructions were included. Fourteen cases (50%) were considered "Complex" due to the addition of meniscal allograft transplantation (8) or meniscal scaffold (3) or high tibial osteotomy (3). The remaining 14 cases (50%) were considered as "Isolate". The mean WOMAC score was 84.6 ± 11.4, Lysholm 81.7 ± 12.3, subjective IKDC 77.2 ± 12.1, and median Tegner score 6 (IQR 5-6) at pre-injury and at final follow-up. Statistically significant inferior values of WOMAC (p = 0.008), Lysholm (p = 0.02) and Subjective IKDC (p = 0.0193) were detected between "Complex" and "Isolate" revision groups. Higher average values of anterior translation at KT-1000 at both 125 N (p = 0.03) and manual maximum displacement test (p = 0.03) were reported in "Complex" with respect to "Isolate" revisions. Four patients were considered as failures and occurred in patients with "Complex" revisions, none occurred in the "Isolate" (30% vs 0%; p = 0.04). CONCLUSION: Good mid-term clinical results can be obtained after repeated ACL revision with allograft in patients who experienced multiple failures; however, those who need additional procedure due to malalignment or post-meniscectomy syndrome reported lower objective and subjective results. LEVEL OF EVIDENCE: III.

Clinical presentation and arthroscopic treatment of hypermobile Type III Wrisberg variant of lateral discoid meniscus: Report of nine cases.

BACKGROUND: The aim of the present study was to document a series of patients with meniscal hypermobility due to a Type III Wrisberg variant lateral discoid meniscus, describing their clinical presentation, analyzing their magnetic resonance imaging (MRI) and arthroscopic characteristics, and reporting the outcomes of an all-inside stabilization. METHOD: Nine cases of Wrisberg variant Type III discoid lateral menisci were identified based on patient's history and clinical examination. Knee MRIs were reviewed to exclude the presence of Type I-II discoid meniscus (complete or incomplete) or bucket handle tears and general arthroscopic criteria. For the Wrisberg variant discoid lateral meniscus were applied for the final diagnosis. RESULTS: All nine cases presented similar peculiar clinical, radiological, and arthroscopic features, which led to the diagnosis of hypermobile Wrisberg variant of lateral discoid meniscus. This rareclinical entity is responsible for suggestive symptoms such as pain, popping and knee locking; moreover, subtle but peculiar MRI and arthroscopic characteristics can be observed. CONCLUSION: Considering the possibility of repeated dislocation and relocation, diagnosis can be challenging, and a high degree of suspicion should be used, especially in young patients, bilateral symptoms, and absence of trauma.

The 25-year experience of over-the-top ACL reconstruction plus extra-articular lateral tenodesis with hamstring tendon grafts: the story so far.

This article presents with an evidence based approach, the kinematical rationale, biological evidence and the long term results of the "Over-The-Top" anterior cruciate ligament reconstruction with lateral plasty technique. This surgery was developed more than 25 years ago at the Rizzoli Institute by professor Marcacci and Zaffagnini and it is still widely performed in many orthopedic center worldwide.

Double-bundle non-anatomic ACL revision reconstruction with allograft resulted in a low revision rate at 10 years.

PURPOSE: This study aimed at reporting the long-term second revision rate and subjective clinical outcomes from a cohort of patients who underwent a double-bundle (DB) ACLR first revision with allograft at a single institution. METHODS: The Institutional database was searched according to the following inclusion criteria: (1) patients that underwent DB-ACL first revision with Achilles tendon allograft, (2) surgery performed between January 2000 and December 2012, (3) age at revision ≥ 18 y/o. Patients' general information, history, surgical data, and personal contacts were extracted from charts. An online survey platform was implemented to collect responses via email. The survey questions included: date of surgeries, surgical data, date of graft failure and subsequent second ACL revision surgery, any other surgery of the index knee, contralateral ACLR, KOOS score, and Tegner scores. RESULTS: Eighty-one patients were included in the survival analysis, mean age at revision 32 ± 9.2 y/o, 71 males, mean BMI 24.7 ± 2.7, mean time from ACL to revision 6.8 ± 5.4 years, mean follow-up time 10.7 ± 1.4 years. There were 12 (15%) second ACL revisions during the follow-up period, three females and nine males, at a mean of 4.5 ± 3 years after the index surgery. The overall survival rates were 85% from a second ACL revision and 68% from all reoperations of the index knee. Considering only the successful procedures (61 patients), at final follow-up, the mean values for the KOOS subscales were 84 ± 15.5 for Pain, 88.1 ± 13.6 for Symptoms, 93 ± 11.6 for ADL, 75 ± 24.5 for Sport, and 71 ± 19.6 for Qol. Twenty-nine (48%) patients performed sports activity at the same level as before ACLR failure. CONCLUSIONS: Double-bundle ACL revision with fresh-frozen Achilles allograft yields satisfactory results at long-term follow-up, with an 85% survival rate from a second ACL revision at mean 10 years' follow-up and good patient-reported clinical scores. LEVEL OF EVIDENCE: Level IV.

Simultaneous medial unicompartmental knee replacement and anterior cruciate ligament reconstruction: a narrative review and technical note.

Background and Objective: Reconstruction of the anterior cruciate ligament (ACL) simultaneously with medial unicompartmental knee arthroplasty (UKA) has been suggested as an alternative treatment in patients with ACL deficiency and localized osteoarthritis (OA) in young patients. The objectives of this review were to report the current concepts on the topic and describe an original surgical technique of simultaneous medial UKA and ACL reconstruction. Methods: A literature search was performed on PubMed, including articles written in English until June 2021. The articles regarding ACL reconstruction and UKA were reviewed using the narrative approach. Inclusion criteria: (I) original articles about ACL reconstruction and unicompartmental knee replacement; (II) written in English; (III) involving three or more cases. Two non-blinded authors reviewed the titles and abstracts of each article identified in the literature search. Key Content and Findings: The articles regarding ACL reconstruction and UKA were reviewed using the narrative approach. Conclusions: There is controversial evidence about performing the UKA simultaneously with an ACL reconstruction. Biomechanical and clinical studies show that the benefits of restoring good joint stability outweigh the possible risks associated with performing both surgeries at the same time. With this strategy, it is possible to obtain good clinical results with a high survival rate of the implant and patient satisfaction.

Objective laxity and subjective outcomes are more influenced by meniscal treatment than anterior cruciate ligament reconstruction technique at minimum2 years of follow-up.

OBJECTIVE: The purposes of this study were: (1) to compare three different surgical techniques for anterior cruciate ligament (ACL) reconstruction at a minimum 2 years of follow-up in terms of objective laxity and patient-reported outcomes; (2) to inspect the role of meniscal tears and treatment alongside with ACL reconstruction. METHODS: 59 patients were randomly assigned to one of the three reconstruction groups according to the ACL reconstruction technique: Double Bundle, Single Bundle, Single Bundle with Lateral Plasty. Autologous hamstring tendons were used in all the ACL reconstruction techniques. Objective laxity tests and KOOS were collected before surgery as a baseline and at a minimum of 2 years of follow-up and compared through a Repeated measure ANOVA. Secondary analysis to evaluate the effect of meniscal treatment on laxity reduction and scores improvement was also conducted using ANOVA. Three laxity evaluations were performed: anterior/posterior displacement at 30° of knee flexion (AP 30), anterior/posterior displacement at 90° of knee flexion (AP 90), and pivot-shift test. RESULTS: Objective laxity and KOOS showed statistically significant improvement at follow-up in all three groups (p < 0.0001) without differences among the techniques. A higher AP 30 (mean difference 2.4 mm, p = 0.0333, ES = 0.66) was found at baseline for the patients with irreparable medial meniscal tear compared to the patients with isolated ACL tear; a statistically significant difference in pain score at two-year follow-up was found between patients who underwent lateral meniscectomy and patients with either meniscal repair (mean difference 6.9 ± 12.5) or isolated ACL tear (mean difference 6.8 ± 16.1); patients with reparable meniscal tear had a statistically significant pain score improvement compared to the patients who underwent medial and lateral meniscectomy (mean difference of 9.5 ± 14.53 and 23.4 ± 19.2 respectively). CONCLUSION: Comparable objective laxity and subjective outcomes were found among the three ACL reconstruction techniques at a minimum of 2 years of follow-up. The presence of irreparable medial meniscal tear increased pre-operative laxity (AP 30, mean difference 2.4 ± 3.6 mm). Patients with meniscal repair presented higher pain relief between baseline and follow-up compared with patients undergoing medial or lateral meniscectomy (mean difference of 9.5 ± 14.53 and 23.4 ± 19.2, respectively).

Reduplicated medial parapatellar plica: a case of a medial plica anatomical variation recalcitrant to conservative treatment.

PURPOSE: The current study aims to report the radiologic and clinical appearance of a rare anatomical variation of the knee medial synovial plica along with its response to conservative and surgical treatment. CASE PRESENTATION: This report portrays a 29-year-old male patient with anteromedial gradual onset right knee pain, aggravated when descending stairs or prolonged sitting. Physical examination revealed medial parapatellar local tenderness, a palpable click in this area when the knee was extended, and hamstring tightness. Magnetic resonance imaging showed a duplicated medial plica, characterized by a high-intensity signal of the infrapatellar fat pad medial portion, after which a presumptive diagnosis of medial plica syndrome was proposed. After conservative treatment failure, the patient underwent standard knee arthroscopy that revealed a superior low profile and an inferior high profile medial plica, and hypertrophy of the medial portion of the infrapatellar fat pad. Both plicae and fat pad were resected with a mechanical shaver until no contact between the femoral trochlea and the fat pad was observed during full range of motion. At 4 weeks postoperatively, symptoms completely resolved, and the patient was allowed to return to full activity with no recurrences at 1 year follow-up. CONCLUSIONS: The current study presented a rare anatomical variation of the knee medial synovial plica that was symptomatic and recalcitrant to conservative treatment. This case report may be useful for radiologists and orthopaedic surgeons to differentiate this special plica type and consider its response to conservative and surgical treatment during patient management.

Clinical outcomes, healing rate, and presence of peri-meniscal cysts after all-inside meniscal repair in combination with anterior cruciate ligament reconstruction: a prospective comparative study with magnetic resonance imaging assessment.

PURPOSE: Meniscal repairs are the most common associated procedures during ACL reconstruction, but they present challenging indications and possible risks of complications or failures. The aim of the present study is to assess the clinical outcomes of all-inside meniscal repairs in the setting of ACL reconstruction. METHODS: Twenty patients with ACL reconstruction and all-inside meniscal repair were compared to 20 patients with isolated ACL reconstruction. All patients were prospectively evaluated pre-operatively, at four month, and 18-month follow-up with KT-1000, Kira accelerometer for pivot-shift, KOOS, Marx score, and SF-36. Meniscal healing and presence of peri-meniscal cysts were assessed on standardized 1.5-T MRIs performed at 18 months. RESULTS: Twenty-one meniscal repairs were performed in 20 patients (81% medial, 19% lateral). At 18 months, 48% had complete healing, 38% had incomplete healing, and 14% had no healing. Peri-meniscal cysts were present in 33% of cases. Worst pre-operative KOOS pain (p = 0.0435) and ADL (p = 0 .0201) were present in patients with meniscal lesion, while no differences were present at four months and 18 months between patients with or without meniscal repair (p > 0.05). No significant differences were noted stratifying patients according to meniscal healing or cyst presence, except of a lower Qol KOOS subscale in patients with peri-meniscal cysts (p = 0.0430). CONCLUSIONS: Meniscal repairs produced good short-term results when performed in combination to ACL reconstruction. Full or partial healing at MRI was present in 86% of cases. One patient out of three developed peri-meniscal cysts.

High return to sport rate and few re-ruptures at long term in professional footballers after anterior cruciate ligament reconstruction with hamstrings.

PURPOSE: Anterior cruciate ligament (ACL) ruptures are considered high burden injuries in sports with high pivotal activity, especially for professional footballers. A lack of evidence exists about long-term follow up of professional elite athletes who underwent ACL reconstruction. The purpose of the study is to analyze the return to play and the career of professional footballers who underwent ACL reconstruction with hamstrings, to evaluate re-rupture and reoperation at either indexed and contralateral knee, and to assess the long-term clinical subjective outcomes and satisfaction. METHODS: Twenty-eight professional footballers that underwent 33 ACL reconstructions were retrospectively included in the study. All surgical interventions were performed using hamstring tendons graft and an over the top technique. Inclusion criteria were: inability to compete due to joint instability caused by total or subtotal ACL lesion, patients contracted to a professional football team at time of surgery. Exclusion criteria were: multi-ligament reconstruction or concomitant meniscal allograft transplantation. Patients were contacted by phone and a brief questionnaire about surgery was administered. Subsequently, a Lysholm knee scoring scale was obtained. After that, an online research was performed on publicly available websites in order to retrieve information of the patients included after surgery. RESULTS: In all cases, ACL Reconstruction was performed with hamstring tendons using a non-anatomic Double-Bundle technique in 16 cases (49%), an Over-The-Top Single-Bundle technique in 9 cases (27%), and an Over-The-Top Single-Bundle plus Lateral Plasty technique in 8 cases (24%); moreover, a meniscal lesion was present in 20 cases (61%). Three (9%) of the 33 ACL reconstruction failed (2/16 Double-Bundle, 1/9 Single- Bundle, 0/8 Single-Bundle + Lateral Plasty; p = n.s.), with two of them within 12 months from surgery. Other procedures, mainly arthroscopic meniscectomies, were performed in 10 cases (30%). The first official match was played after an average of 8.0 ± 3.6 (4.6-18.2) months in 31 cases (94%). Patients were evaluated after 12.6 ± 3.3 years (6.7-17.5) from the indexed ACL reconstruction. The average Lysholm score was 94.2 ± 8.3. CONCLUSIONS: In our small case-series, professional soccer players were able to return to play at a competitive level with a hamstrings over the top technique. Patients with long careers had a high percentage of reoperation on the contralateral knee. LEVEL OF EVIDENCE: IV.

High recall bias in retrospective assessment of the pediatric International Knee Documentation Committee Questionnaire (Pedi-IKDC) in children with knee pathologies.

PURPOSE: The increasing incidence of knee injuries among children is well known by sports physicians. Papers dealing with this topic have often collected patient-reported outcomes measures (PROMs) in a retrospective manner; this limitation could lead to a misinterpretation of the results, because pediatric patients might not remember their preoperative conditions adequately. This study aims to evaluate the reliability and the reproducibility of the IKDC pediatric score when administered retrospectively at a 12-month follow-up. METHODS: From September 2018 and June 2019, all patients aged 7-18 scheduled for surgery due to different knee pathologies in a single center were considered eligible. Parents were contacted by phone for consent. An open-source platform was implemented to collect the responses: two surveys were created (Q1, Q2). They included general information and the Pedi-IKDC score. Q1 was completed prospectively, while Q2 was completed 12 months after surgery. The two questionnaires were identical, and patients were carefully advised to complete Q2 recalling their health status before surgery. ICC and the concordance correlation coefficient (ρc) were used to assess the reproducibility between the prospective and recalled scores. RESULTS: Sixty-six patients responded to Q1 and Q2, and the mean age was 12.9 ± 2.2 years at Q1 and 14.1 ± 2.2 years at Q2. The mean time between Q1 and Q2 was 14.1 ± 2.1 months. Between prospective-IKDC and recall-IKDC, the ICC coefficient was "poor" at 0.32 (CI 0.09 to 0.5) and the ρc was "poor" at 0.4 (CI 0.29 to 0.51). Mean prospective-IKDC was 76.8 ± 23.52 mean recalled-IKDC was 60.4 ± 11.5 (P < 0.0001), while mean difference was -16.3 ± 2.09. Simple linear regression models showed that Δ-IKDC is independently associated with age at Q1 (R2 = 0.2676; P0.0001) and prospective-IKDC (R2 = 0.653; P < 0.0001). CONCLUSIONS: Retrospective collection of the Pedi-IKDC score is not reliable and has high recall bias. This should be avoided in children with knee conditions. LEVEL OF EVIDENCE: III.

Side-to-side anterior tibial translation on monopodal weightbearing radiographs as a sign of knee decompensation in ACL-deficient knees.

PURPOSE: To evaluate the influence of time from injury and meniscus tears on the side-to-side difference in anterior tibial translation (SSD-ATT) as measured on lateral monopodal weightbearing radiographs in both primary and secondary ACL deficiencies. METHODS: Data from 69 patients (43 males/26 females, median age 27-percentile 25-75: 20-37), were retrospectively extracted from their medical records. All had a primary or secondary ACL deficiency as confirmed by MRI and clinical examination, with a bilateral weightbearing radiograph of the knees at 15°-20° flexion available. Meniscal status was assessed on MRI images by a radiologist and an independent orthopaedic surgeon. ATT and posterior tibial slope (PTS) were measured on the lateral monopodal weightbearing radiographs for both the affected and the contralateral healthy side. A paired t-test was used to compare affected/healthy knees. Independent t-tests were used to compare primary/secondary ACL deficiencies, time from injury (TFI) (≤ 4 years/ > 4 years) and meniscal versus no meniscal tear. RESULTS: ATT of the affected side was significantly greater than the contralateral side (6.2 ± 4.4 mm vs 3.5 ± 2.8 mm; p < 0.01). There was moderate correlation between ATT and PTS in both the affected and healthy knees (r = 0.43, p < 0.01 and r = 0.41, p < 0.01). SSD-ATT was greater in secondary ACL deficiencies (4.7 ± 3.8 vs 1.9 ± 3.2 mm; p < 0.01), patients with a TFI greater than 4 years (4.2 ± 3.8 vs 2.0 ± 3.0 mm; p < 0.01) and with at least one meniscal tear (3.9 ± 3.8 vs 0.7 ± 2.2 mm; p < 0.01). Linear regression showed that, in primary ACL deficiencies, SSD-ATT was expected to increase (+ 2.7 mm) only if both a meniscal tear and a TFI > 4 years were present. In secondary ACL deficiencies, SSD-ATT was mainly influenced by the presence of meniscal tears regardless of the TFI. CONCLUSION: SSD-ATT was significantly greater in secondary ACL deficiencies, patients with a TFI greater than 4 years and with at least one meniscal tear. These results confirm that SSD-ATT is a time- and meniscal-dependent parameter, supporting the concept of gradual sagittal decompensation in ACL-deficient knees, and point out the importance of the menisci as secondary restraints of the anterior knee laxity. Monopodal weightbearing radiographs may offer an easy and objective method for the follow-up of ACL-injured patients to identify early signs of soft tissue decompensation under loading conditions. LEVEL OF EVIDENCE: Level III.

Anterior Cruciate Ligament Reconstruction and Lateral Plasty in High-Risk Young Adolescents: Revisions, Subjective Evaluation, and the Role of Surgical Timing on Meniscal Preservation.

BACKGROUND: In adolescents, the rate of meniscal injury at the time of anterior cruciate ligament (ACL) reconstruction, the rate of ACL graft revision, and clinical outcomes has not yet been investigated. HYPOTHESIS: In patients younger than 16 years, the rate of meniscal injuries at the time of ACL reconstruction increases with time from injury. The mid-term revision rate and reoperation rate after ACL reconstruction with hamstrings and lateral tenodesis are lower than those reported in literature for isolate ACL reconstruction. STUDY DESIGN: Case series. LEVEL OF EVIDENCE: Level 4. METHODS: Patients younger than 16 years who underwent ACL reconstruction with hamstring and lateral tenodesis, with a follow-up ≥2 years were included. The number of meniscal lesions was stratified according to the delay between injury-to-surgery (<3, 3-12, >12 months). All reoperations, Lysholm score, Knee Injury and Osteoarthritis Outcome Score subscales for pain (at rest and during activity), and return to sport were collected. RESULTS: A total of 151 patients (mean age 14.8 ± 1.2 years) were included. Patients undergoing surgery at <3 months after injury had a lower meniscal injury rate (36%) than those treated at 3 to 12 months (55%) and >12 months (63%) after injury (P = 0.04). Medial meniscal lesions were more likely to be repaired when surgery was performed <3 months after injury (91%). Subjective follow-up data were available for 132 patients, and 19 were lost to follow-up. At 6.0 ± 2.6 years, 6% of patients underwent ACL revision; 1 of 20 (5%) patients with posterior tibial slope ≥12° and 4 of 45 (9%) patients with Tegner level ≥8. Nine new meniscal procedures were performed; 19% of repaired menisci underwent meniscectomy. Good or excellent Lysholm score was reported by 88% of patients; 56% of patients with concurrent lateral meniscectomy had pain during activity, 91% returned to sport, and 79% were still participating at final follow-up. CONCLUSION: Patients younger than 16 years undergoing ACL reconstruction within 3 months from injury had the lowest rate of meniscal injuries. ACL reconstruction with lateral tenodesis had low revision rate (6%) and good or excellent clinical outcomes in 88% of young adolescents. CLINICAL RELEVANCE: Sport physicians should be aware that adolescent patients undergoing ACL reconstruction within 3 months after injury have the lowest rate of meniscal injuries; the mid-term revision rate of ACL reconstruction with lateral plasty is lower than 10% and the patients' perceived outcomes are good with almost all patients returning to sport activity.

Anterior cruciate ligament reconstruction with lateral plasty restores anterior-posterior laxity in the case of concurrent partial medial meniscectomy.

PURPOSE: To evaluate the in vivo knee laxity in the presence of a partial medial meniscectomy before and after a single-bundle ACL reconstruction with a lateral plasty (SBLP) and to compare it with the knee laxity after a single-bundle ACL reconstruction (SB). METHODS: One-hundred and one patients with ACL tear were enrolled in the study and grouped according to the surgical technique and the meniscus treatment: regarding the SBLP technique (n = 55), 31 patients underwent isolated ACL reconstruction ("SBLP Isolated ACL Group"), while 24 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SBLP ACL + MM Group"); regarding the SB technique (n = 46), 33 patients underwent isolated ACL reconstruction ("SB Isolated ACL Group"), while 13 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SB ACL + MM Group"). Anterior-posterior clinical laxity at 30° (AP30) and 90° (AP90) of knee flexion was quantified before and after surgery through a surgical navigation system dedicated to kinematic assessment. RESULTS: In the ACL-deficient status, the antero-posterior laxity was significantly higher in the presence of a combined MM in both the AP30 and the AP90, with no differences between the two surgical techniques. After the ACL reconstruction, both AP30 and AP90 translations decreased significantly (p < 0.0001) compared to the ACL-deficient status. No differences were found for AP30 and AP90 between SBLP Isolated ACL and SBLP + MM groups, while a significantly higher AP90 translation was found for the SB + MM group compared to the SB Isolated ACL group. Moreover, the AP90 translation in the SB ACL + MM group was significantly higher than the one of the other three groups, i.e., SBLP ACL + MM, SB, and SBLP Isolated ACL group. CONCLUSION: The ACL reconstruction with lateral plasty reduced the AP knee laxity caused by the medial meniscectomy in the context of an ACL surgery. LEVEL OF EVIDENCE: Level II.

Biomechanics of the lateral meniscus: evidences from narrative review.

Lateral meniscus plays a crucial role in the knee stability and function. Although complex settings are required for lateral meniscus biomechanical assessment, such characteristics have been investigated over time to optimize the daily clinical practice surgical procedure. The aim of the present study was to provide an overview of literature knowledge regarding the biomechanics of lateral meniscus and give further insights about novel experimental analyses. Studies regarding lateral meniscus mobility, effect on knee laxity, and contact mechanics were included in the review. The effect of meniscal lesion, meniscal repair, partial meniscectomy, and meniscus allograft transplantation were retrieved for either in vivo, cadaveric, or in-silico computational settings. Knee laxity was evaluated both in presence of isolated meniscal tears and in anterior cruciate ligament (ACL) deficient knees. Surgical navigation systems and robots were mainly used for the investigations in vivo and in cadaveric studies, while accelerometers emerged as an alternative for ambulatory assessments. Contact mechanics was only assessed in cadaveric and computational studies. Great effort has been put into exploring lateral meniscus biomechanics from multiple perspectives. Strong evidence emerged regarding the importance of lateral meniscus repair: increased knee stability at high degrees of knee flexion and reduction of peak contact pressures on tibial cartilage were the most reported benefits. The meniscus allograft transplantation also emerged as a concrete solution for irreparable tears and further studies are needed to investigate its long-term influence on knee stability.

The hypermobile and unstable lateral meniscus: a narrative review of the anatomy, biomechanics, diagnosis and treatment options.

Objective: The purpose of this review is to improve the awareness of lateral meniscal hypermobility by describing its relevant anatomy, biomechanics, pathophysiology, imaging and arthroscopic findings as well as the treatment options. Background: The lateral meniscus is less stable than the medial meniscus. Its important posterior stabilizers are the popliteomeniscal fascicles, the posterior capsule, the meniscofemoral ligaments and the posterior meniscotibial ligament, which are divided by a bare area, the popliteal hiatus. Atraumatic insufficiency or rupture of one of these key structures may impact the mobility of the lateral meniscus and can lead to an unstable, hypermobile lateral meniscus. Lateral meniscus hypermobility can cause lateral knee pain and mechanical symptoms as locking. Ruptures of the popliteomeniscal fascicles are frequently associated with anterior cruciate ligament and posterolateral corner injuries. Their repair may be important to fully restore knee stability. Methods: This is a narrative overview of the literature synthesizing current knowledge about the hypermobile lateral meniscus. Anatomy, biomechanics, diagnosis and treatment of this entity was of particular interest for this review. Literature was retrieved from PubMed database, hand searches and cross-reference checking. Conclusions: Diagnosing lateral meniscus hypermobility is challenging since the magnetic resonance imaging are often unspecific and may show no structural alterations of the meniscus and its attachments. The only hint can be the patient's history and clinical symptoms (e.g., locking). Ultimately, the diagnosis is confirmed during knee arthroscopy, when the lateral meniscus can be mobilized over 50% of the lateral tibial plateau or lateral femoral condyle while anterior probing or by using the aspiration function during arthroscopy. Treatment includes stabilizing the posterior lateral meniscus by repairing the injured structures. Therefore, a systematic arthroscopic evaluation of the lateral compartment is important to fully recognize the problem. Repair can be achieved arthroscopically with various suturing techniques used for meniscal repair with satisfactory results and low recurrence rates.