An Observational Prospective Clinical Study for the Evaluation of a Collagen-Hydroxyapatite Composite Scaffold in Hip Revision Surgery.

One of the greatest challenges of hip revision surgery is the need to restore extensive bone loss by creating a stable reconstruction with long-term durability. The present observational, investigator-initiated prospective study was carried out to evaluate the clinical and radiological results of the use of a commercial biomimetic collagen-hydroxyapatite composite biomaterial (RegenOss) applied in hip revision surgery. Thirty-three patients who underwent hip revision were included in this study, and 29 received up to 2 years of follow-up. The acetabulum was reconstructed using an uncemented hemispherical shell both with or without an iliac fixation stem. Functional recovery was assessed according to the Harris Hip Score (HHS) at the pre-hospitalisation check-up, and at 6-, 12-, and 24-month follow-ups. Radiological evaluation consisting of X-ray analyses (6, 12, and 24 month follow-ups) and CT scan exams (within 10 weeks post-surgery and at 12-month follow-up) were performed to evaluate the reduction in bone defect and new bone regeneration. All the patients reported a complete recovery and a considerable improvement in functional outcome assessed by the HHS, which was significantly higher at all the follow-ups than at pre-hospitalisation. Moreover, radiological assessments revealed good scaffold integration. Overall, collected data suggest that RegenOss is a valid and safe alternative to restoring acetabular bone loss in revision hip arthroplasty.

Cell-Free Biomimetic Osteochondral Scaffold for the Treatment of Knee Lesions: Clinical and Imaging Results at 10-Year Follow-up.

BACKGROUND: Cell-free devices have been introduced to restore osteochondral defects, avoiding the limitations of cell-based procedures. Among these, an osteochondral scaffold made of type I collagen and hydroxyapatite has been investigated with promising results up to medium-term follow-up. However, the clinical and imaging results over time still need to be documented. PURPOSE: To evaluate the clinical outcome and tissue maturation at long-term follow-up after the implantation of the osteochondral scaffold. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 24 patients (7 women, 17 men; age, 36 ± 9.5 years) underwent surgical implantation of the osteochondral scaffold and were prospectively evaluated before surgery, at 2-, 5-, and 10-year follow-up. The mean defect size was 2.9 ± 1.4 cm2. Patients were evaluated using the International Knee Documentation Committee (IKDC) subjective and objective scores, and the activity level was documented with the Tegner score. Magnetic resonance imaging (MRI) evaluation involved the use of the magnetic resonance observation of cartilage repair tissue score combined with 5 more variables focused on the bone layer. RESULTS: A statistically significant improvement of all clinical scores was documented from the baseline to the final evaluation. The IKDC subjective score improved from the preoperative level to 2 years (41 ± 13.2 and 77.1 ± 14.6, respectively) (P < .0005), with stable results up to 10 years (77.4 ± 19.4). The IKDC objective score changed from 52% of normal and nearly normal knees before the treatment to 84% at 10 years (P < .0005). Tegner sports activity at the final evaluation (3.8 ± 1.7) was higher compared with the preoperative level (1.6 ± 1.1; P < .05), but it remained significantly lower compared with the preinjury level (5.5 ± 2.6; P < .05). Treatment failed in 1 patient. Persisting graft alterations were observed on MRI scans, although without correlating with the clinical outcome. CONCLUSION: The regenerative potential of this scaffold is limited, as demonstrated by the signal alterations persisting over time on MRI scans. On the other hand, the clinical improvement was significant and stable over time both in terms of subjective and objective outcomes, including activity level, with overall good results.

Weight bearing versus conventional CT for the measurement of patellar alignment and stability in patients after surgical treatment for patellar recurrent dislocation.

PURPOSE: To compare weight-bearing cone-beam computer tomography (CBCT) and conventional computer tomography (CT)-based measurements of patellofemoral alignment and stability in patients surgically treated for recurrent patellar dislocation. These scans implied respectively single-leg up-right posture, the knee flexed, and lower limb muscles activation, versus supine position with the knee extended. METHODS: A total of 17 patients (11 males/6 females) after surgical reconstruction with fascia lata allograft for recurrent patellofemoral dislocation were analyzed at 60-month follow-up. Tilt and congruence angles and tibial tuberosity-trochlear groove (TT-TG) offset were measured on images obtained from CBCT and conventional CT scans by three independent and expert radiologists. Paired t tests were performed to compare measurements obtained from the two scans. Inter-rater reliability was assessed using a two-way mixed-effects model intra-class correlation coefficient (ICC). RESULTS: Only TT-TG offset was found significantly smaller (p < 0.001) in CBCT (mean 9.9 ± 5.3 mm) than in conventional CT (mean 15.9 ± 4.9 mm) scans. ICC for tilt and congruence angles and for TT-TG offset ranged between 0.80-0.94 with measurements in CBCT scans, between 0.52 and0.78 in conventional CT. CONCLUSION: In patients surgically treated for recurrent patellar dislocation, TT-TG offset was found overestimated with conventional CT. All measurements of patellofemoral stability and alignment were found more consistent when obtained with weight-bearing CBCT compared to conventional CT.

Autologous chondrocytes versus filtered bone marrow mesenchymal stem/stromal cells for knee cartilage repair-a prospective study.

PURPOSE: To document clinical, radiologic, and cellular data of a prospective patient series treated by a tri-layer collagen-hydroxyapatite biomimetic osteochondral scaffold (CHAS) intra-operatively seeded with cultivated autologous chondrocytes (AC) or with filtered bone marrow stem/stromal cells (fBMSC) to address chronic osteochondral knee lesions. METHODS: Thirty-six consecutive patients (15 to 59 years) with chronic osteochondral lesions (1.8-10 cm2) in the condylar or patellofemoral knee surfaces were enrolled. Lesions were covered with CHAS fixed with a fibrin glue. The superficial layer of CHAS was intra-operatively injected with active cells: in initial five patients, ACs were put directly onto dry CHAS (dry-AC); next, eight AC patients had CHAS moistened with cell culture media (media-AC), while the tourniquet was released allowing blood soaking of CHAS in the rest (14 blood-AC, 9 blood-fBMSC). Seventeen (50%) patients required different concomitant procedures. All patients were followed for serious adverse events (SAE) or graft failures; clinical, radiographic, and MRI evaluation was conducted. Cellular data on the injected cells were assessed. RESULTS: At a follow-up of 39 months (16-81), 17 patients required an additional surgical intervention: seven graft-related SAE (early post-operative synovitis and/or arthrofibrosis) were registered (3 dry-AC, 3 media-AC, 1 blood-fBMSC). There were two graft failures (1 dry-AC, 1 blood-fBMSC) for secondary reasons. All clinical scores significantly improved from pre- to post-operative values: IKCD subjective 44 to 65; IKDC examination (9/17/5/5) to (20/10/5/1); KOOS (P61/S59/ADL67/Sp32/QoL31) to (P79/S75/ADL84/Sp55/QoL51); Tegner activity scale 3.3 to 4.4. There was evidence of radiographic osteoarthritis progression-Kellgren-Lawrence 1.0 to 1.5. MOCART scores at the final follow-up averaged 71 (10 to 95). Graft-type analysis demonstrated an increased rate of graft-related SAE in dry-AC and media-AC, but their final outcomes were equivalent. Cellular data of AC at the implantation were as follows: cells in suspension 9.2 × 106, viability 95%. In blood-fBMSC group, a cell suspension with 87% viability was injected, which contained 1156 CFU-Fs. CONCLUSION: CHAS with intra-operative seeding of active cells, either AC or fBMSC, led to an overall successful outcome for the treatment of chronic osteochondral lesions in the knee. Blood soaking of CHAS in situ before cell seeding significantly decreased early post-operative adverse events, such as synovitis and arthrofibrosis.

Matrix-assisted chondrocyte transplantation with bone grafting for knee osteochondritis dissecans: stable results at 12 years.

PURPOSE: To document clinical and radiological results of arthroscopic matrix-assisted autologous chondrocyte transplantation (MACT) combined with bone grafting for the treatment of knee osteochondritis dissecans (OCD) at long-term follow-up. METHODS: Thirty-one knees in 29 patients (20.4 ± 5.7 years) were treated for symptomatic unfixable OCD lesions (2.6 ± 1.1 cm2) and prospectively evaluated at 2, 5, and 12 years (average, minimum 10 years). Patients were evaluated over time with IKDC subjective score, EQ-VAS, and Tegner scores. Failures were also documented. At the final follow-up, MRI evaluation was performed in 14 knees with the MOCART 2.0 score. RESULTS: Beside 4 early failures, an overall clinical improvement was documented: the IKDC subjective score improved from 39.9 ± 16.8 to 82.1 ± 17.0 and 84.8 ± 17.2 at 2 and 5 years, respectively (p < 0.0005), and remained stable for up to 12 years (85.0 ± 20.2). EQ-VAS and Tegner scores presented similar trends, but patients did not reach their original activity level. Worse results were obtained for lesions bigger than 4 cm2. At MRI evaluation, subchondral bone abnormalities were detected in over 85% of knees at long-term follow-up. CONCLUSIONS: Arthroscopic bone grafting followed by MACT for unfixable knee OCD can offer a promising and stable clinical outcome over time in lesions smaller than 4 cm2, with a low failure rate of 13%. Persistent subchondral alterations were documented at long-term MRI evaluation, suggesting the limits of this approach to regenerate the osteochondral unit in patients affected by knee OCD. LEVEL OF EVIDENCE: IV.

A multilayer biomaterial for osteochondral regeneration shows superiority vs microfractures for the treatment of osteochondral lesions in a multicentre randomized trial at 2 years.

PURPOSE: The increasing awareness on the role of subchondral bone in the etiopathology of articular surface lesions led to the development of osteochondral scaffolds. While safety and promising results have been suggested, there are no trials proving the real potential of the osteochondral regenerative approach. Aim was to assess the benefit provided by a nanostructured collagen-hydroxyapatite (coll-HA) multilayer scaffold for the treatment of chondral and osteochondral knee lesions. METHODS: In this multicentre randomized controlled clinical trial, 100 patients affected by symptomatic chondral and osteochondral lesions were treated and evaluated for up to 2 years (51 study group and 49 control group). A biomimetic coll-HA scaffold was studied, and bone marrow stimulation (BMS) was used as reference intervention. Primary efficacy measurement was IKDC subjective score at 2 years. Secondary efficacy measurements were: KOOS, IKDC Knee Examination Form, Tegner and VAS Pain scores evaluated at 6, 12 and 24 months. Tissue regeneration was evaluated with MRI MOCART scoring system at 6, 12 and 24 months. An external independent agency was involved to ensure data correctness and objectiveness. RESULTS: A statistically significant improvement of all clinical scores was obtained from basal evaluation to 2-year follow-up in both groups, although no overall statistically significant differences were detected between the two treatments. Conversely, the subgroup of patients affected by deep osteochondral lesions (i.e. Outerbridge grade IV and OCD) showed a statistically significant better IKDC subjective outcome (+12.4 points, p = 0.036) in the coll-HA group. Statistically significant better results were also found for another challenging group: sport active patients (+16.0, p = 0.027). Severe adverse events related to treatment were documented only in three patients in the coll-HA group and in one in the BMS group. The MOCART score showed no statistical difference between the two groups. CONCLUSIONS: This study highlighted the safety and potential of a biomimetic implant. While no statistically significant differences were found compared to BMS for chondral lesions, this procedure can be considered a suitable option for the treatment of osteochondral lesions. LEVEL OF EVIDENCE: I.

One-Step Treatment for Patellar Cartilage Defects With a Cell-Free Osteochondral Scaffold: A Prospective Clinical and MRI Evaluation.

BACKGROUND: The treatment of symptomatic cartilage defects of the patella is particularly challenging, and no gold standard is currently available. PURPOSE: To evaluate the clinical results of a biphasic cell-free collagen-hydroxyapatite scaffold and to evaluate osteochondral tissue regeneration with magnetic resonance imaging (MRI). STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Thirty-four patients (18 men and 16 women; mean ± SD: age, 30.0 ± 10 years) were treated by scaffold implantation for knee chondral or osteochondral lesions of the patella (area, 2.1 ± 1 cm2). The clinical evaluation was performed prospectively at 12 and 24 months via the IKDC (International Knee Documentation Committee; objective and subjective) and Tegner scores. MRI evaluation was performed at both follow-ups in 18 lesions through the MOCART score (magnetic resonance observation of cartilage repair tissue) and specific subchondral bone parameters. RESULTS: A statistically significant improvement in all the scores was observed at 12- and 24-month follow-up as compared with the basal evaluation. The IKDC subjective score improved from 39.5 ± 14.5 to 61.9 ± 14.5 at 12 months ( P > .0005) with a further increase to 67.6 ± 17.4 at 24 months of follow-up (12-24 months, P = .020). The MRI evaluation showed a stable value of the MOCART score between 12 and 24 months, with a complete filling of the cartilage in 87.0% of the lesions, complete integration of the graft in 95.7%, and intact repair tissue surface in 69.6% at final follow-up. The presence of osteophytes or more extensive bony overgrowth was documented in 47.8% of the patients of this series, but no correlation was found between MRI findings and clinical outcome. CONCLUSION: The implantation of a cell-free collagen-hydroxyapatite osteochondral scaffold provided a clinical improvement at short-term follow-up for the treatment of patellar cartilage defects. Women had lower outcomes, and the need for realignment procedures led to a slower recovery. MRI evaluation showed some abnormal findings with the presence of bone overgrowth, but no correlation has been found with the clinical outcome.

Magnetic resonance-guided focused ultrasound treatment of extra-abdominal desmoid tumors: a retrospective multicenter study.

OBJECTIVES: To assess the feasibility, safety and preliminary efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) for the treatment of extra-abdominal desmoid tumours. METHODS: Fifteen patients with desmoid fibromatosis (six males, nine females; age range, 7-66 years) were treated with MRgFUS, with seven patients requiring multiple treatments (25 total treatments). Changes in viable and total tumour volumes were measured after treatment. Efficacy was evaluated using an exact one-sided Wilcoxon test to determine if the median reduction in viable tumour measured immediately after initial treatment exceeded a threshold of 50 % of the targeted volume. Median decrease after treatment of at least two points in numerical rating scale (NRS) worst and average pain scores was tested with an exact one-sided Wilcoxon test. Adverse events were recorded. RESULTS: After initial MRgFUS treatment, median viable targeted tumour volume decreased 63 %, significantly beyond our efficacy threshold (P = 0.0013). Median viable total tumour volume decreased (105 mL [interquartile range {IQR}, 217 mL] to 54 mL [IQR, 92 mL]) and pain improved (worst scores, 7.5 ± 1.9 vs 2.7 ± 2.6, P = 0.027; average scores, 6 ± 2.3 vs 1.3 ± 2, P = 0.021). Skin burn was the most common complication. CONCLUSIONS: MRgFUS significantly and durably reduced viable tumour volume and pain in this series of 15 patients with extra-abdominal desmoid fibromatosis. KEY POINTS: • Retrospective four-centre study shows MRgFUS safely and effectively treats extra-abdominal desmoid tumours • This non-invasive procedure can eradicate viable tumour in some cases • Alternatively, MRgFUS can provide durable control of tumour growth through repeated treatments • Compared to surgery or radiation, MRgFUS has relatively mild side effects.

Hamstring graft tibial insertion preservation versus detachment in anterior cruciate ligament reconstruction: a prospective randomized comparative study.

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction with hamstring graft (HG) is a commonly performed procedure. Despite the type of reconstruction chosen, the detached HG undergoes a remodeling process known as ligamentization. In order to shorten the ligamentization process, the maintenance of HG tibial insertion, aimed to spare the tendons vascular supply, has been postulated. The aim of this paper is to report the results of a prospective randomized study comparing clinical and MRI results between two different ACL reconstructive procedures with and without HG tibial insertion preservation. METHODS: Forty patients (mean age 27.5 ± 9.5 years) were enrolled and randomly divided into two groups. The study group underwent an ACL reconstruction using a distally inserted HG, while the control group underwent a technique encompassing HG tibial detachment. Subjective and objective IKDC score was administered preoperatively and at 3-, 6-, 12- and 24-month follow-up. Graft morphology was assessed through MRI evaluation performed at 6-month follow-up. RESULTS: Clinical results were excellent in both groups. Regarding MRI results, a better intra-articular graft morphology was observed in the study group (Tau = 0.313, p = 0.024). No differences in graft integration were noticed. CONCLUSION: The main finding of this preliminary study is that preservation of the hamstring tibial insertion seems to enhance graft ligamentization with improved morphology of the intra-articular portion of the graft compared to a detachment of the hamstring tendons from the tibial side. Further well-designed studies with higher number of patients as well as more serial MRI evaluations are required to validate these preliminary findings.

Anterior cruciate ligament injury: post-traumatic bone marrow oedema correlates with long-term prognosis.

PURPOSE: Bone marrow oedema (BME) in the knee is a feature of several pathological conditions, and it has been described with high frequency in patients with acute anterior cruciate ligament (ACL) injury. The aim of this study is to evaluate the significance of BME, assessed in MRIs performed for ACL injury, with regards to clinical outcome and return to sport. METHODS: A total of 134 patients (98 men, 36 women) with ACL tear and MRI knee scan within six months from trauma were analysed. The presence of BME was evaluated on MRI images considering: extension and hyperintensity, the WORMS score oedema classification, and measuring the BME area. The clinical results were documented by IKDC-subjective score and the sport activity level by Tegner score at a minimum of five years follow up. RESULTS: BME was present in 74 knees (55.2 %), with a mean area of 523 ± 370 mm². The presence of BME showed a gradual decrease over time (p = 0.008), being detectable in MRIs performed more than three months after trauma in just 25.0 % of cases. Although 54 % of the patients without BME after three months returned to their previous sport level, no patients with oedema reached a full sport recovery (p = 0.01). In the group that underwent ACL reconstruction, the BME area was significantly correlated with a return to the previous sport level at the mid/long-term follow-up (p = 0.038). CONCLUSIONS: BME is a common finding, which decreases over time after injury. However, when BME is still detectable it correlates with clinical prognosis, and even in sport-active patients undergoing ACL reconstruction, a higher BME area is a negative predictive factor for a successful outcome at the mid/long-term follow-up.

Biodegradable polyurethane meniscal scaffold for isolated partial lesions or as combined procedure for knees with multiple comorbidities: clinical results at 2 years.

PURPOSE: The aim of this study is to evaluate the safety and clinical efficacy of this novel polyurethane meniscal scaffold to treat partial meniscal loss. METHODS: Eighteen patients (11 men and 7 women, mean age: 45 years) affected by irreparable acute meniscal tears requiring partial meniscectomy or chronic prior loss of meniscal tissue were enrolled in the study. They underwent arthroscopic polyurethane meniscal scaffold implantation (13 medial and 5 lateral) and, in case of presence of other comorbidities, concurrent procedures were also performed. Patients were prospectively evaluated up to 2 years of follow-up through IKDC objective, IKDC subjective, and Tegner scores. Furthermore, MRI evaluation of the meniscal scaffold was performed. RESULTS: No major adverse events were observed. A statistically significant increase in all the clinical parameters considered was found. The IKDC objective score increased from 61 % of normal or nearly normal knees at basal evaluation to 94 % at 2 years of follow-up (p = 0.01). There was also a significant increase in the IKDC subjective score both at 6-12 months of follow-up (p = 0.03 and p < 0.005), which was confirmed at 24 months. The Tegner score also showed a significant increase from the pre-operative level (median value 2, range 1-5) to final evaluation (median value 3, range 2-5; p = 0.005), albeit not reaching the pre-injury sports activity level. CONCLUSIONS: The implantation of this novel polyurethane scaffold proved to be a safe and potentially effective procedure to treat partial meniscal loss with encouraging results at short-term follow-up. Further high-quality studies with larger numbers of patients and longer evaluation times are needed to confirm these preliminary data.

Is the clinical outcome after cartilage treatment affected by subchondral bone edema?

PURPOSE: Subchondral bone edema is a common finding after cartilage treatment, but its interpretation is still debated. The aim of this study is to analyse the presence of edema after matrix-assisted autologous chondrocyte transplantation (MACT) for knee cartilage lesions at different follow-up times and its correlation with the clinical outcome. METHODS: Two hundred and forty-eight magnetic resonance imagings (MRIs) of patients treated with a hyaluronic acid-based MACT for lesions of the knee articular surface were considered. The MRIs belonged to 116 patients (mean age at surgery 28.6 ± 10.3 years, average defect size 2.4 ± 1.0 cm(2)), 57 affected by degenerative cartilage lesions, 27 traumatic and 32 were osteochondritis dissecans (OCD). MRI follow-up was performed from 6 to 108 months after treatment. Other than its presence or absence, the subchondral bone edema was evaluated using a 3-level grading considering extension and hyperintensity, and with the WORMS score edema classification. The IKDC subjective score was collected at the time of every MRI. RESULTS: An analysis of the entire MRI group showed that edema is not constantly present through the follow-up, but presents a particular and well-defined trend. Edema was present within the first 2 years and was then markedly reduced or disappeared at 2 and 3 years (p = 0.044). Afterwards the level of edema increased again (p < 0.0005) and remained steadily present at medium/long-term follow-up. Patellar lesions presented significantly lower edema (p = 0.012), whereas OCD lesions presented more edema at all follow-up (p = 0.002) and a different trend, with an increasing level of edema over time. No correlation was found between edema and clinical outcome. CONCLUSIONS: Edema after MACT is present during the first phases of cartilage maturation up to 2 years of follow-up, and then tends to disappear. However, after a few years, it tends to reappear. Less edema was found in the patella, whereas more edema was found in the OCD, where subchondral bone is primarily involved. Interestingly, the presence of edema was not correlated with a poorer clinical outcome. Whether this might be a prognostic factor at longer follow-up remains to be determined, but our results give some indication on what to expect on both MRI edema and clinical outcome after MACT. LEVEL OF EVIDENCE: Case series, Level IV.

Arthroscopic collagen meniscus implantation for partial lateral meniscal defects: a 2-year minimum follow-up study.

BACKGROUND: Loss of knee meniscal tissue often leads to increased pain and decreased function. HYPOTHESIS: At a minimum 2-year follow-up, patients receiving a lateral collagen meniscus implant (CMI) would show improved knee function and decreased pain compared with their preoperative status. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty-four patients with irreparable lateral meniscal tears (n = 7) or previous partial lateral meniscectomy (n = 17) underwent arthroscopic lateral collagen meniscus implantation. Clinical evaluation was performed preoperatively, at 6 months, and at a minimum 2-year follow-up with Lysholm, visual analog scale (VAS) for pain, Tegner, objective International Knee Documentation Committee (IKDC), and EuroQol 5 dimensions (EQ-5D) scores. A magnetic resonance imaging (MRI) evaluation was performed preoperatively and at final follow-up using the modified Yulish score for cartilage and the Genovese score for implant size and signal intensity. RESULTS: All clinical scores significantly improved from preoperative evaluation to final follow-up. Average Lysholm scores improved from 64.0 ± 16.2 to 92.7 ± 13.8 (P < .0001), VAS for pain from 55.2 ± 29.4 to 19.5 ± 25.6 (P < .0001), Tegner from 3 (interquartile range, 2-4) to 5 (interquartile range, 4-7) (P = .0062), objective IKDC from 6A, 14B, 4C to 20A, 3B, 1D (P = .0002), and EQ-5D from 0.58 ± 0.28 to 0.89 ± 0.14 (P < .0001). Good to excellent (A + B) objective IKDC scores improved from 83% preoperatively to 96% at 2-year follow-up. The Tegner index (the percentage of the lost activity level that was regained as a result of the treatment intervention) was 47% at 6-month follow-up and 79% at 2-year follow-up: this improvement was statistically significant (P = .0062). The MRI evaluations for tibial and femoral modified Yulish scores for cartilage remained similar over the course of the study; 87.5% of implants were reduced in size, and in 3 cases (12.5%), they were completely resorbed; 50% of the implants had a slightly hyperintense signal (relative to the normal meniscus), and signal intensity changes suggested that full maturation had occurred in 37.5% at final follow-up (based on the Genovese scores). CONCLUSION: The lateral CMI demonstrated that it was safe in this population study, with decreased pain and improved knee function in 96% of patients with excellent/good Lysholm results in 87% of patients at a minimum 2-year follow-up. The MRI scans demonstrated a decreased implant size relative to a normal meniscus.

Human dermal matrix scaffold augmentation for large and massive rotator cuff repairs: preliminary clinical and MRI results at 1-year follow-up.

The high incidence of recurrent tendon tears after repair of massive cuff lesions is prompting the research of materials aimed at mechanically or biologically reinforcing the tendon. Among the materials studied upto now, the extracellular matrix (ECM) scaffolds of human origin have proved to be the safest and most efficient, but the current laws about grafts and transplants preclude their use in Europe. In order to overcome this condition in 2006, we started a project regarding the production of an ECM scaffold of human origin which could be implanted in Europe too. In 2009, the clinical study began with the implantation of dermal matrix scaffolds in 7 middle-aged patients affected with large/massive cuff lesions and tendon degeneration. Out of 5 cases, followed for at least 1 year in which the scaffold was employed as an augmentation device, there were 3 patients with complete healing, 1 partial re-tear, and 1 total recurrence. The absence of adverse inflammatory or septic complications allows to continue this line of research with a prospective controlled study in order to define the real advantages and correct indications offered by scaffold application.

Novel nano-composite multilayered biomaterial for osteochondral regeneration: a pilot clinical trial.

BACKGROUND: In recent years, there has been an increasing interest in and awareness of the importance of subchondral bone, for its role in the pathogenesis of articular surface damage and for the care that should be taken when treating such damage. PURPOSE: The objective of this pilot clinical study was to test the safety and performance of a newly developed type I collagen-hydroxyapatite nanostructured biomimetic osteochondral scaffold that aims to regenerate cartilage and subchondral bone. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A multilayer gradient nano-composite scaffold was obtained by nucleating collagen type I fibrils with hydroxyapatite nanoparticles. Thirty patients (9 female, 21 male; mean age, 29.3 years) with knee chondral or osteochondral lesions were treated with scaffold implantation. Lesion size varied from 1.5 cm(2) to 6.0 cm(2). Twenty-eight patients were followed for 2 years and were clinically evaluated using the International Knee Documentation Committee and Tegner scores. At final follow-up, magnetic resonance imaging evaluation was performed in 24 patients, and they were evaluated with the MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) score. RESULTS: The Tegner and International Knee Documentation Committee objective and subjective scores improved significantly from the baseline evaluation to the 6-, 12-, and 24-month follow-ups. Further analysis showed a slower recovery but the same results for patients who presented with adverse events, for older patients, for patients who underwent previous surgery, and for those with patellar lesions. In contrast, a faster recovery was observed in active patients. At magnetic resonance imaging evaluation, complete filling of the cartilage and complete integration of the graft was shown in 70% of the lesions. However, the subchondral lamina and bone were considered intact in a minority of cases (7% and 47%, respectively). CONCLUSION: This open 1-step procedure was used for the treatment of chondral and osteochondral knee defects. The present pilot study highlighted the safety and potential clinical benefit of the graded biomimetic osteochondral scaffold in promoting bone and cartilage tissue restoration by itself and with good clinical and magnetic resonance imaging results at the 2-year follow-up.

Knee osteochondral autologous transplantation: long-term MR findings and clinical correlations.

We evaluated long-term magnetic resonance imaging (MRI) features of Knee Osteochondral Autologous Transplantation (OAT)-Mosaicplasty and correlated MRI findings and clinical outcome. Twenty-four patients (mean age 29.9±8.7, 70.8% male) undergoing arthroscopic OAT between 1997 and 2000 were prospectively enrolled. The International Cartilage Repair Society (ICRS)/International Knee Documentation Committee (IKDC) scores and Tegner scores were employed for clinical evaluation. The magnetic resonance observation of cartilage repair tissue (MOCART) was utilized for description and assessment of the repair tissue. Median follow up was 113 months (interquartile range [IQR] 106-122). MRI showed good survival of grafted cartilage in 62.5% of patients. The integration of the graft was complete in 75% of cases, while the repaired tissue was intact in 62.5% and had an homogeneous structure in 70.8%. The MOCART score significantly correlated with objective and subjective scores (p=0.003 and p=0.002). Contrastingly, overall MOCART showed no correlation with the Tegner score. MRI revealed to be a powerful tool for non-invasive long-term assessment of OAT.

MR imaging of bone metastases and choice of sequence: spin echo, in-phase gradient echo, diffusion, and contrast medium.

Magnetic resonance imaging (MRI) is the only imaging technique allowing the direct visualization of the bone marrow and is the most sensitive to detect bone metastases. Sensitivity is high, but a good understanding and an informed choice of acquisition sequences can easily improve specificity. Fat and water distribution (spin echo), indirect visualization of bone trabeculae (in-phase gradient echo), evaluation of bone edema and cell density (diffusion), and the study of vascularization (contrast medium) should be cleverly combined to enable good detection and lesion characterization.

Arthroscopic autologous osteochondral grafting for cartilage defects of the knee: prospective study results at a minimum 7-year follow-up.

BACKGROUND: Articular cartilage lesions, with their inherent limited healing potential, remain a challenging problem for orthopaedic surgeons. Various approaches have been proposed to treat these lesions; nevertheless, opinions on indications and clinical efficacy of these techniques are still controversial. PURPOSE: To evaluate the outcome of osteochondral autografts for treatment of femoral condyle cartilage lesions at a medium-to long-term follow-up. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We prospectively evaluated 30 patients (mean age, 29.3 years) with full-thickness knee chondral lesions (<2.5 cm(2)) treated with arthroscopic autologous osteochondral transplantation. Thirteen patients underwent previous surgery, while 17 patients were operated on for the first time. In 19 patients, associated procedures were performed. All patients were evaluated at 2- and 7-year follow-up. The International Cartilage Repair Society form, Tegner score, and magnetic resonance imaging were used for clinical evaluation. RESULTS: The International Cartilage Repair Society objective evaluation showed 76.7% of patients had good or excellent results at 7-year follow-up, and International Knee Documentation Committee subjective score significantly improved from preoperative (34.8) to 7-year follow-up (71.8). The Tegner evaluation showed a significant improvement after the surgery at 2- and 7-year follow-up (from 2.9 to 6.2 and 5.6, respectively); however, we noticed reduced sports activity from 2- to 7-year follow-up. Magnetic resonance imaging evaluation showed good integration of the graft in the host bone and complete maintenance of the grafted cartilage in more than 60% of cases. CONCLUSION: The results of this technique at medium- to long-term follow-up are encouraging. This arthroscopic 1-step surgery appears to be a valid solution for treatment of small, grade III to IV cartilage defects.