Meniscal Scaffold Implantation Research Articles

Usefulness of Probing Sensor Device for Evaluating Meniscal Suture and Scaffold Implantation.

Appropriate suture tension is a key factor in successful meniscal repair. This study aimed to clarify the appropriate value of meniscal stabilization with suture repair based on a probing procedure for healthy porcine menisci and a novel meniscal scaffold. After evaluating the reliability of the probing sensor, meniscal vertical tear and partial meniscectomy models were developed, in which suture repair and meniscal scaffold implantation were performed at suture intervals ranging between 20 and 2.5 mm. The residence forces at each interval were evaluated using a probing sensor. Moreover, a tensile test was conducted to evaluate the displacement and presence or absence of gaps. We found that normal and meniscal scaffolds should be fixed within 5 mm of suture interval. The probing residence forces required were at least 1.0 N for vertical tears and 3.0 N for meniscal scaffolds. These findings may be taken into consideration to reduce suture failure following meniscal tear repair and stabilizing meniscal scaffold fixation.

Clinical Outcomes After Polyurethane Meniscal Scaffolds Implantation Remain Stable Despite a Joint Space Narrowing at 10-Year Follow-Up

To report the clinical outcomes, radiologic evolution, and survivorship of a series of patients affected by the postmeniscectomy syndrome and treated with a polyurethane scaffold at a minimum 10-year follow-up. In addition, the radiologic evolution of these patients was also assessed. All the patients operated on with a polyurethane meniscal scaffold implantation to treat postmeniscectomy syndrome from 2008 to 2011 were prospectively followed. Clinical evaluations and radiologic studies were assessed at the preoperative period, at 5-year follow-up, and at minimum 10-year follow-up. Clinical outcomes were based on patient-reported outcomes (e.g., the Knee injury and Osteoarthritis Outcome Score, International Knee Documentation Committee, Lysholm, and Tegner). Radiographical evaluation of the joint-space narrowing was done in the Rosenberg view. Failure was defined as patients who required surgery to remove the scaffold or those patients who needed surgery for a total or partial knee replacement. Twenty-one of 27 patients, with a mean age of 56 ± 9.8 years, were available for the final follow-up. The mean follow-up was 11.8 (range, 10-12.7) years. Six patients were lost to follow-up. All functional scores showed a significant improvement (P < .001) at the 5- and 10-year follow-up. The exception was the Tegner score, which remained stable. The joint-space width was maintained from the preoperative period (1.9 ± 1.2 mm) up to the 5-year follow-up (1.3 ± 1.5 mm, P= .3) and decreased by the last evaluation (0.6 ± 1.2 mm, P= .001) at the last follow-up. Two (9.5%) of 21 patients were converted to a total knee replacement during the study period. None of the other patients needed revision surgery during the study period. The polyurethane meniscal scaffold provides significant and stable pain relief over time and improved functional outcomes at a minimum of 10 years after surgery. However, degenerative changes progressed in the treated compartment, with a joint-space narrowing over the 10-year period. Level IV, retrospective case series.

Risk Factors Affecting the Survival Rate of Collagen Meniscal Implant for Partial Meniscal Deficiency: An Analysis of 156 Consecutive Cases at a Mean 10 Years of Follow-up

Background: Collagen meniscal implant (CMI) is a biologic scaffold that can be used to replace meniscus host tissue after partial meniscectomy. The short-term results of this procedure have already been described; however, little is known about risk factors for failure. Purpose: To determine the factors that predict failure of meniscal scaffold implantation in a large series of patients treated at a single institution and to better define the indications for surgery. Study Design: Case-control study; Level of evidence, 3. Methods: The analysis included 186 consecutive patients with a minimum 5-year follow-up who underwent CMI scaffold implantation or combined procedures. Patients’ characteristics and details of the surgery were obtained via chart review. Patients with a Lysholm score <65 were considered to have experienced clinical failure. Surgical failure was defined as partial or total scaffold removal. Results: The final analysis included 156 patients (84%) at a mean follow-up of 10.9 ± 4.3 years. The patients’ mean age at surgery was 42.0 ± 11.1 years, and the survival rate was 87.8%. Subgroup analysis identified Outerbridge grade 3-4 (Hazard ratio [HR], 3.8; P = .004) and a lateral meniscal implant (HR, 3.2; P = .048) as risk factors for failure. The survival rate was 90.4% for medial implants and 77.4% for lateral implants. An Outerbridge grade 3-4 (HR, 2.8; P < .001) and time from meniscectomy to scaffold >10 years (HR, 2.8; P = .020) were predictive of surgical or clinical failure. Conclusion: CMI for partial meniscal deficiency provided good long-term results, with 87.8% of the implants still in situ at a mean 10.9 years of follow-up. Outerbridge grade 3-4, lateral meniscal implants, and longer time from the meniscectomy to implantation of the CMI were identified as risk factors for clinical and surgical failure.

Paper 31: Risk factors affecting the survival rate of Collagen Meniscus Implant (CMI) for partial meniscus deficiency. An analysis of 156 consecutive cases at a mean 10 years of follow-up

Objectives:The present study aimed to determine the factors that predict failure of meniscus scaffold implantation in a large series of patients treated at a single institution, to better refine the indications for surgery and better inform future patients.Methods:156 consecutive patients with a minimum 5-year follow-up who underwent isolate CMI scaffold implantation or combined procedures were included in the analysis. Demographic and surgical information were obtained via chart review. Patients with partial meniscal deficiency requiring CMI implant, who had an Outerbridge grade of at least 3 and also underwent an additional surgery were considered as “complex cases”. Patients were asked to complete the Lyshlom questionnaire and those with a “poor” Lysholm score (<65 points) were considered a clinical failure. Patients were also inquired regarding further reoperations on the ipsilateral knee during the follow-up period to determine the incidence of surgical failure, defined as partial or total scaffold removal.Results:156 patients (84%) with a mean age at surgery of 42.0 ± 11.1 were included in the final analysis at an average follow-up of 10.9 ± 4.3 years. The overall survival rate from surgical failure was 87.8%. When further evaluating the different subgroups of patients, an Outerbridge grade of III-IV (HR 3.8; P =.004) and lateral scaffold (HR, 3.2; P= .0048) were identified as risk factors In the specific, the overall survival rate of the medial scaffold was 90.4%, while the survival rate of the lateral one was 77.4%. Finally, 42 patients (26.9%) were considered either a surgical or clinical failure. In this case, risk factors identified were: an Outerbridge grade of III-IV (HR, 3.1; P =.000), and time from meniscectomy to scaffold greater than 10 years (HR, 2.7; P = .042).Conclusions:Collagen meniscus implant for partial meniscus deficiency provided good long-term results, with 87.8% of the implants still in-situ at a mean 10.9 years of follow-up. The cartilage status, laterality of the scaffold, and time from meniscectomy to CMI surgery were identified to affect significantly clinical and/or surgical failures.

Clinical application of polyurethane meniscal scaffold: A meta-analysis

ObjectiveIn patients with partial meniscus defect, the implantation of polyurethane meniscal scaffold has become a common method for the treatment of meniscus vascular entry and tissue regeneration. However, it is unclear whether polyurethane meniscal scaffold will yield better clinical and MRI results after surgery. This meta-analysis compared the clinical and MRI results of polyurethane meniscal scaffold in some patients with meniscus defects. MethodsBy searching PubMed, Embase, and Cochrane Library, a systematic review of studies evaluating the clinical outcomes of patients with polyurethane meniscal scaffold implantation. The search terms used are: “meniscus”, “meniscal”, “scaffold”, “Actifit” “polyurethane” and “implant”. The study was evaluated based on the patient's reported outcome score, accompanying surgery, and radiology results. Genovese scale was used to evaluate morphology and signal intensity, and Yulish score was used to evaluate the imaging performance of articular cartilage. ResultsThere were 16 studies that met the inclusion criteria, a total of 613 patients, and the overall average follow-up time was 41 months. The clinical scores at the final follow-up, such as VAS, IKDC, Tegner, and KOOS, were significantly improved compared with preoperatively. The MS, SI, and IIRMC scores evaluated in MRI showed no significant difference between preoperative and final follow-up. However, for AC (OR 0.34, 95% CI 0.11–1.00; P = 0.05) and AME (OR 0.08, 95% CI 0.03–0.22; P < 0.01), the final follow-up results were worse than preoperatively. ConclusionsThis meta-analysis found that compared with preoperative, the clinical effect of the final follow-up was significantly improved. However, MS, SI, and IIRMC in MRI parameters did not change significantly. In addition, the final follow-up results of AC and AME showed a deteriorating trend. Therefore, for patients with partial meniscus defects, polyurethane meniscal scaffold seem to be a viable option, and further research is needed to determine whether the deterioration of AC and AME is clinically relevant.

Meniscal polyurethane scaffold plus cartilage repair in post meniscectomy syndrome patients without malalignment improves clinical outcomes at mid-term follow-up

BackgroundThe aim of this study is to report the mid-term follow-up results of a prospective cohort of patients who underwent a polyurethane (PU) meniscal scaffold implantation for post meniscectomy syndrome (PMS), without limb realignment procedures. MethodsProspective study in patients with PU meniscal scaffolds implanted during 2014–2016. Limb realignment procedures excluded. Clinical outcomes were prospectively evaluated pre-operatively and every year post-operatively using patient-reported outcome scores (KOOS, VAS, Lysholm and IKDC). Post-operative radiologic evaluation was done using 3.0 T magnetic resonance imaging (MRI). Meniscal scaffold extrusion, signal intensity, tibio-femoral cartilage degeneration progression and complications were analyzed. ResultsFourteen patients with an average age of 25.8 years (range: 17–47) received a PU scaffold (8 lateral and 6 medial). Associated procedures were done in all patients, with an osteochondral allograft transplantation (OAT) being the most common. Mean follow up was 51.6 (range: 39–66) months. Post-operative mean clinical outcomes scores showed significantly improved results compared to the pre-operative scores. Lysholm scores increased from 62.4 to 80.2 (P = 0.0023), KOOS from 68.9 to 80 (P = 0.0083) and VAS for pain decreased from 5.3 to 3.1 (P = 0.0024). Average post-operative IKDC score was 67.7. There were 8 cases of complete extrusion (>3 mm). The mean extrusion value was 4.0 mm (range: 3–6 mm). Three patients showed signs of a ruptured meniscal scaffold. One patient showed progression of the cartilage degenerative process. ConclusionThe use of a PU scaffold, associated with other surgical procedures in the knee, especially chondral repair, had a significant improvement in clinical outcomes compared to the baseline status, at an average of 51.6 months follow-up in patients suffering from PMS. Although imaging results show a high proportion of implant extrusion, this does not appear to imply a worsening in clinical outcomes in the short term. Level of evidenceIV. Case series.

Functional and magnetic resonance imaging outcome after polyurethane meniscal scaffold implantation following partial meniscectomy.

Prevention of the knee osteoarthritis following meniscectomy is implantation of an allotransplant or an artificial meniscus. We present retrospective study of our early results of the treatment using polyurethane meniscal scaffold. From 2016 to 2020, we implanted nine polyurethane scaffolds (Actifit) after partial meniscectomy, five males and four females, age 36 (16-47), BMI 26.7 (17.2-35.9) kg/m2. Functional status, activity, pain, and MRI were assessed. FU 20.8 (6-48.5) months, 35.2 (0-68) months from the meniscectomy to the implantation. The average implant length was 46.1 (35-60) mm, average number of sutures was 7.6 (5-10). Lysholm score before surgery was 61.7 (49-85), after the surgery 86.4 (62-95) with p 0.0045, Tegner activity score before meniscectomy was 5.8 (4-7), after 3.8 (2-5), and after the scaffold implantation 4.6 (3-7) with p 0.0488. Before surgery, VAS score was 3.1 (2-4), and after 7.7 (5-9) with p 0.0042. Pursuant to the Genovese classification, the last follow-up MRI showed a type 2 meniscal morphology in four cases and a type 3 in five cases. Seven patients had type 1 and two had type 2 signal intensity. On average, the absolute extrusion of a transplanted meniscus was 3.67mm, and the relative extrusion was 0.58mm. Extrusion progress was not detected. Significantly improved knee functionality, increased level of physical activity, and reduced pain. MRI analysis revealed the meniscal transplant morphology and volume loss, as well as its extrusion without progression.

Muscle strength but not balance improves after arthroscopic biodegradable polyurethane meniscus scaffold application.

This study aimed to assess the impact of biodegradable polyurethane meniscus scaffold implantation (BPMSI) on muscle strength and balance in comparison with the healthy contralateral knee in patients with irreparable medial meniscus defect. This observational and prospective case-cohort study was conducted with patients who had irreparable meniscal defects and underwent arthroscopic meniscus scaffold implantation. Surgeries were carried out on the medial meniscus of 16 right and 4 left knees. Visual analog scale (VAS) was used to assess the degree of pain relief. Knee Injury and Osteoarthritis Outcome Score (KOOS) and Lysholm (LYS) score were used to evaluate the functional improvement at weeks 12, 24 and 36. Concentric and eccentric quadriceps and hamstring peak torque (PT) as well as the peak torque-to-body weight (PTB) ratio, anterior-posterior, mediolateral and overall stability indexes were assessed at the same time points. Twenty male patients with a mean age and body mass index of 32.2 ± 8.8years and 26.2 ± 4.2kg/m2, respectively, were included in the study. The amount of pain decreased from 7.6 ± 1.5% to 2.9 ± 1.5% at postoperative week 36. Range of motion, Lysholm score and KOOS increased from 87.0ο ± 9.5ο to 115.0ο ± 15.1ο, 30.8 ± 4.3 to 81.5 ± 5.3 and 37.4 ± 5.3 to 74.1 ± 7.2, respectively. Concentric quadriceps and hamstring peak torque values and peak torque/body weight ratios were improved in the knees that received a meniscus scaffold implant. Anterior/posterior, medial/lateral, and overall stability indexes with or without biofeedback exhibited a slight improvement, which was not statistically significant. BPMSI led to decreased pain and improved function at postoperative week 36. Although muscle strength almost returned to normal, balance parameters did not recover within 36weeks after the procedure.

Lateral Meniscus Replacement Using Peroneus Longus Tendon Autograft

Nowadays, several techniques are available for preserving the lateral aspect of the knee after meniscectomy; meniscus transplantation is the gold standard, and meniscus scaffold implantation is an effective alternative. However, meniscus transplantation is technically difficult and has many potential complications, whereas scaffolds resorb over time. Autografts are commonly used for labroplasty in shoulder and hip surgeries. We attempted to adapt this technique to the knee, using autografts for meniscus replacement. In this report, we describe a meniscus-replacement technique, using a peroneus longus autograft, for lateral meniscus deficits. This technique significantly simplifies the procedure and is cost effective, and thus can be considered as an alternative technique for preventing osteoarthritis of the lateral aspect of the knee.

Medial Meniscus Scaffold Implantation in Combination with Concentrated Bone Marrow Aspirate Injection: Minimum 3-Year Follow-up

The objective of this study is to show the short-term clinical and radiological outcomes of concentrated bone marrow aspirate (CBMA) injection administered in combination with medial meniscus scaffold implantation. Twenty-three patients who received intra-articular CBMA injection in combination with polyurethane-based medial meniscus scaffold implantation were evaluated within the scope of this study. The International Knee Documentation Committee (IKDC) questionnaire and the Knee injury and Osteoarthritis Outcome Score (KOOS) were used to evaluate the results, and the visual analog scale was used to assess the pain scores. Magnetic resonance imaging (MRI) scans were obtained in the preoperative period and at postoperative months 1, 12, 24, and 36 to assess the scaffold position as well as chondral degeneration/damage in a comparative manner. MRI assessment was performed by using the modified Outerbridge scale for cartilage and the Genovese scoring system for the meniscal implant. Twenty-three patients who were included in the study were evaluated for a mean follow-up period of 38.3 months. Patients exhibited statistically significant improvement according to all scoring data from the preoperative period until the follow-up period. The mean postoperative extrusion at year 3 was 2.39 mm (distribution 2.30-2.56 mm). There was no significant difference in the distribution of the degree of chondral damage between the preoperative and 3-year follow-up periods. Four patients did not show any improvement nor had lower scores according to the assessment. Medial meniscus scaffold implantation combined with intra-articular CBMA injection resulted in a significant improvement in all functions and pain scores as well as a statistically significant clinical improvement in IKDC and KOOS values in the short-term follow-up. The Level of evidence for this study is IV.

Polyurethane scaffold implants for partial meniscus lesions: delayed intervention leads to an inferior outcome

The purpose of this study was to assess the clinical outcomes of the implantation of an aliphatic polyurethane scaffold for the treatment of partial loss of meniscal tissue at a mean follow-up of 36months. A retrospective review on prospectively collected data was performed on patients who underwent implantation of an aliphatic polyurethane-based synthetic meniscal scaffold. Patients were evaluated for demographics data, lesion and implant characteristics (sizing, type and number of meniscal sutures), previous and combined surgeries and complications. Clinical parameters were rated using NRS, IKDC subjective, Lysholm, KOOS, and Tegner activity score, both preoperatively and at final follow-up. Sixty-seven patients were evaluated at a mean follow-up of 36months (48 M and 19 F; mean age 40.8 ± 10.6years; mean BMI 25.4 ± 4.3). The scaffold was implanted on the medial side in 54 cases, and on the lateral one in 13. Forty-seven patients had undergone previous surgical treatment at the same knee and 45 required combined surgical procedures. All evaluated scores improved significantly from the baseline. Among possible prognostic factors, a delayed scaffold implantation had lower post-operative clinical scores: IKDC subjective (P = 0.049), KOOS Sport (P = 0.044), KOOS total (p = 0.011), and Tegner (P = 0.03) scores at follow-up. The polyurethane meniscal scaffold implantation led to a significant clinical benefit in a large number of patients. A delayed intervention correlated with worse results. IV.

Magnetic Resonance Imaging and Functional Outcomes After a Polyurethane Meniscal Scaffold Implantation: Minimum 5-Year Follow-up

To report the magnetic resonance imaging (MRI) and clinical outcomes at a minimum 5-year follow-up in a series of patients with postmeniscectomy syndrome and treated with a polyurethane scaffold. All consecutive patients operated on from September 2008 to February 2011 for either persistent medial or lateral joint line compartmental pain receiving a polyurethane scaffold due to a previous partial meniscus resection with a minimum 5-year follow-up were included. Functional scores (Knee Injury and Osteoarthritis Outcomes Score, International Knee Documentation Committee, Lysholm, and Tegner) were assessed preoperatively and at the last follow-up. The state of the scaffold as well as postoperative scaffold extrusion and the total remaining meniscal volume was also evaluated in MRI. Thirty-two patients were included. The mean follow-up was 70.8 ± 7.5months. The functionality of the knees improved in all the scores used (P < .001) except for the Tegner score that stayed steady. Most of meniscal implants showed extrusion of 2.4mm (95% confidence interval [CI], 1.1-3.7) were smaller and a hyperintensity signal was seen in the MRI. Three scaffolds were resorbed at the last follow-up. The meniscal volume, determined by MRI, was 1.14cm3 (95% CI, 0.96-1.31) preoperatively and 1.61cm3 (95% CI, 1.43-1.7) at the last follow-up. No differences were presented. Theuse of a polyurethane meniscal scaffold in patients with a symptomatic meniscus deficit had a good functional outcome at 5years after surgery. However, the implanted scaffolds did not present normal meniscal tissue with MRI, and the implant volume was considerably less than expected. The fact that most of patients included received different concomitant procedures during scaffold implantation introduces a degree of performance bias into the results. Level IV, case series.

Similar clinical outcomes following collagen or polyurethane meniscal scaffold implantation: a systematic review.

The purpose of this systematic review is to evaluate the current literature in an effort to assess specific clinical outcomes following meniscal scaffold implantation using the two available scaffolds: Collagen Meniscal Implant (CMI) and the Actifit polyurethane meniscal scaffold. A systematic review was performed by searching PubMed, Embase, and Cochrane Library to find studies evaluating clinical outcomes of patients undergoing meniscal scaffold implantation. Search terms used were "meniscus", "meniscal", "scaffold", and "implant". Studies were evaluated based on scaffold type, treatment failure rates, patient-reported outcome scores, concomitant procedures, and radiological findings. Radiological findings were recorded using the Genovese scale to assess morphology and signal intensity and the Yulish score to assess articular cartilage. Nineteen studies (1 level I, 1 level II, 17 level IV evidence) were identified that met inclusion criteria, including a total of 658 patients (347 Actifit, 311 CMI). The overall average follow-up was 45 months. Treatment failure occurred in 9.9% of patients receiving the Actifit scaffold at a mean follow-up of 40 months and 6.7% of patients receiving CMI at a mean follow-up of 44 months (n.s.). However, the rate of failure ranged from 0 to 31.8% amongst the included studies with a variable definition of failure. Additionally, overlapping patients and presence of concomitant surgeries such as anterior cruciate ligament reconstruction (ACLR) and high tibial osteotomy (HTO) may have a significant influence on these results. Outcomes for the Visual Analog Scale (VAS) for pain, Lysholm knee score, and Tegner activity score improved from preoperatively to latest follow-up in both groups, while the Knee Injury and Osteoarthritis Outcome Score and International Knee Documentation Committee scores improved from preoperatively to latest follow-up for Actifit scaffold patients. Overall, patients receiving CMI scaffolds had higher grades for Genovese morphology and signal intensity when compared to Actifit scaffold patients. Patients undergoing meniscal scaffold implantation with either CMI or Actifit scaffold can both be expected to experience improvement in clinical outcomes when used in association with concomitant procedures such as ACLR and HTO. IV, systematic review.

Polyurethane meniscal scaffolds lead to better clinical outcomes but worse articular cartilage status and greater absolute meniscal extrusion.

Implantation of polyurethane (PU) meniscal scaffolds has become a popular procedure to provide a scaffold for vessel ingrowth and meniscal tissue regeneration in patients with partial meniscal defects. However, it is unclear whether PU meniscal scaffolds lead to better clinical and magnetic resonance imaging (MRI) outcomes post-operatively. This meta-analysis compared the clinical and MRI outcomes in patients with partial meniscal defects treated with PU meniscal scaffolds. This meta-analysis reviewed all studies that assessed Lysholm score, International Knee Documentation Committee (IKDC) score, visual analogue scale (VAS) for pain, Tegner score, Knee Injury and Osteoarthritis Outcomes Score (KOOS), articular cartilage (AC), absolute meniscal extrusion (AME), morphology and size (MS), signal intensity (SI) of meniscal implant, and interface of the implant-residual meniscus complex (IIRMC) in patients with partial meniscal defects treated with PU meniscal scaffolds. Eighteen studies were included in the meta-analysis. The proportion of patients who evaluated MS (OR 0.71, 95% CI 0.38-1.33; n.s.), SI (OR 1.07, 95% CI 0.53-2.18; n.s.), and IIRMC (OR 1.00, 95% CI 0.33-3.06; n.s.) did not differ significantly between baseline and final follow-up. However, AC (OR 0.31, 95% CI 0.11-0.84; P=0.02) and AME (OR 0.05, 95% CI 0.01-0.18; P<0.00001) worsened between baseline and final follow-up. Conversely, Lysholm score (95% CI -1.87 to -1.07; P<0.00001), IKDC score (95% CI -2.19 to -1.08; P<0.00001), VAS for pain (95% CI -2.29 to -1.07; P<0.00001), Tegner score (95% CI -0.76 to -0.15; P=0.003), and overall KOOS (95% CI -29.48 to -23.17; P<0.00001) were significantly greater at final follow-up when compared to baseline. This meta-analysis found no significant differences in the tested MRI parameters, including MS, SI, and IIRMC. However, AC and AME worsened between baseline and final follow-up. Conversely, patients treated with PU meniscal scaffolds showed significant functional improvement and pain relief when compared with baseline scores. Thus, PU meniscal scaffolds appear to be a viable alternative for patients with partial meniscal defects, although further studies are needed to determine whether worsened AC and AME are clinically relevant. In particular, precise measurement of PU meniscal scaffolds in combination with thorough investigation of the baseline articular cartilage status and meniscal defect size may be effective for pain relief or functional improvement in patients with PU meniscal scaffold implantation. III.

Polyurethane-based cell-free scaffold for the treatment of painful partial meniscus loss.

The aim of this study was to document, at mid-term follow-up, the clinical and MRI outcome of a polyurethane-based cell-free scaffold implanted to treat painful partial meniscus loss. Eighteen consecutive patients were enrolled and treated with arthroscopic polyurethane meniscal scaffold implantation and, in case of other comorbidities, with concurrent surgical procedures: 16 patients (9 men and 7 women, mean age 45±13years, mean BMI 25±3, 12 medial and 4 lateral implants) were prospectively evaluated with the subjective and objective IKDC and the Tegner scores at 24, 36, 48, 60, and 72months of follow-up. Eleven patients were also evaluated by 1.5-T MRI at the final follow-up. The IKDC subjective score showed a significant improvement from baseline to 24months (45.6±17.5 and 75.3±14.8, respectively; p=0.02) and subsequent stable results over time for up to 72months (final score 75.0±16.8). The Tegner score improvement between pre-operative status and final follow-up was also significant (p=0.039). Nevertheless, the final score remained significantly lower than the pre-injury sports activity level (p=0.027). High-resolution MRIs documented the presence of abnormal findings in terms of morphology, signal intensity, and interface between the implant and the native meniscus. Implant extrusion and bone oedema at the treated compartment were also observed in most of the cases, even though no correlation was found between imaging findings and clinical outcome. The present study reports satisfactory clinical outcomes at mid-term follow-up after polyurethane-based meniscal cell-free scaffold implantation. The treatment was effective both in cases of isolated partial meniscal lesions and in complex cases requiring the combination with other surgical procedures. On the other hand, a high rate of altered MRI aspects was documented. However, no correlation was found between the altered imaging parameters and the overall positive clinical findings, thus supporting the use of this procedure to treat painful partial meniscus loss. Case series, Level IV.

Association of a hi-tech with a bio-tech technique in the treatment of early osteoarthritis of the knee: a case report.

Meniscal replacement to treat early osteoarthritis of the knee after meniscectomy may be accompanied by other surgical procedures to treat factors predisposing to a negative intervention outcome. Overload of the medial compartment in slight varus can be reduced by applying the new KineSpring system, which can promote the best possible outcome of a biodegradable meniscal scaffold implantation, without producing biomechanical and anatomical alterations of the joint. This is the first case report on the combination of these hi-tech and bio-tech techniques.

Meniscal scaffolds.

There are two scaffold products designed for meniscal reconstruction or substitution of partial meniscal defects that are currently available in the Europe: the collagen meniscal implant (CMI; Ivy Sports Medicine, Gräfelfing, Germany) and the polymer scaffold (PS; Actifit, Orteq Bioengineering, London, United Kingdom). The CMI has demonstrated improved clinical outcomes compared with baseline in patients with chronic postmeniscectomy symptoms with follow-up ranging from 5 to more than 10 years. There are also several comparative studies that report improved clinical scores in patients with chronic medial meniscus symptoms treated with CMI versus repeat partial meniscectomy, and a lower reoperation rate. Recently, PS insertion was shown to result in improved clinical outcomes in patients with chronic postmeniscectomy symptoms of the medial or lateral meniscus at short-term follow-up. However, there is currently no medium- or long-term data available for the PS. The use of meniscal scaffolds in the acute setting has not been found to result in improved outcomes in most studies. The authors' surgical indications for meniscal scaffold implantation, preferred surgical technique, and postoperative rehabilitation protocol are described.

Meniscal scaffolds: results and indications. A systematic literature review.

The aim of this systematic review was to document the available clinical evidence to support meniscal scaffold implantation, analysing results and indications for the treatment of meniscal loss. The systematic review of the literature was performed searching three medical electronic databases: PubMed, Scopus, and the Cochrane Collaboration. The guidelines for preferred reporting items for systematic reviews and meta-analysis (PRISMA) were used. Relevant data were then extracted and collected in a unique database with consensus of two observers. To assess the methodological quality of the collected data, the subscales of a modified Coleman methodology score (CMS) were determined. A total of 23 studies on two scaffolds (CMI, Ivy Sports Medicine GmbH, Germany; Actifit, Orteq, United Kingdom) met the inclusion criteria and were used for the final analysis, of which more than half have been published in the last three years. Good clinical results have been documented in 613 patients, mainly young men affected by symptomatic chronic lesions, with a cumulative failure rate of 6.1% and presence of newly formed tissue documented both at histological and MRI evaluation in most cases. However, there is a lack of comparative trials and the average study quality is low. An increase in publications regarding this topic has been seen recently, due to the introduction in the clinical practice of the second synthetic scaffold. Safety and positive results have been shown for both scaffolds. Although, literature lacks randomized trials at long-term follow-up to confirm real potential and most appropriate indications of meniscal scaffold implantation.

Polyurethane scaffold for the treatment of partial meniscal tears. Clinical results with a minimum two-year follow-up.

to evaluate the safety and effectiveness of the polyurethane meniscal scaffold through clinical examination, MRI and arthroscopic second look, over a minimum two-year follow-up. between 2009 and 2011, 19 patients underwent meniscal scaffold implantation in our department (medial meniscus in 16 cases lateral meniscus in two cases, and bilateral in one case). All the patients were clinically evaluated preoperatively, and at 6, 12, and 24 months after surgery using Lysholm score, Tegner score, and VAS. Ten patients were studied with MRI, and nine patients were evaluated arthroscopically. no adverse reactions to the implant were observed. The clinical scores showed a significant improvement at 6 months and increased progressively over time. On MRI studies, the implants showed a clear hyperintense signal, sometimes irregular, and the chondral surface was preserved in all cases. At arthroscopic second look in the first months after surgery, the scaffold size was unchanged and the scaffold appeared light yellowish in color and well integrated into the surrounding tissues. At arthroscopic second look at 12 and 24 months the scaffold was found to have an irregular morphology and to be slightly reduced in size. polyurethane meniscal scaffold is a good alternative to a collagen scaffold, but a longer follow-up is needed to evaluate the scaffold degradation and chondral coverage. level IV, therapeutic case series.

Osteochondral scaffold reconstruction for complex knee lesions: a comparative evaluation

BackgroundThe primary aim of the present study is to evaluate the results obtained in challenging knee lesions with the implant of an osteochondral scaffold and concomitant treatment of all comorbidities. The secondary aim is to compare the results obtained with those found when a chondral scaffold was applied. Materials and methodsPatients affected by complex lesions of the knee articular surface were included. “Complex cases” were defined according to the following criteria: previous clinical history of intra-articular fracture, lesion located at the tibial plateau, concurrent knee axial realignment procedure, concurrent meniscal scaffold or allograft implantation, and multiple articular surface lesions treated. Thirty-three patients were treated with the implantation of an osteochondral scaffold. The results of a homogeneous group of 23 patients previously treated and prospectively evaluated after implantation of a chondral scaffold were analyzed and compared. ResultsIKDC subjective score improved significantly from pre-operative (40.4±14.1) to 12months' follow-up (69.6±17.0; p<0.0005) with a further improvement at the final evaluation at 24months (75.5±15.0; p=0.038). The same positive trend was confirmed by the VAS and Tegner scores. At final follow-up the group treated with the osteochondral scaffold presented a better subjective IKDC score with respect to the group treated with the chondral scaffold (p=0.034). ConclusionsA regenerative procedure to address the entire osteochondral unit, together with the treatment of all comorbidities, might offer good results also in complex cases otherwise doomed to non-biological resurfacing. Level of evidence IIIComparative study.