Understanding the Role of Surface Modification of Randomized Trabecular Titanium Structures in Bone Tissue Regeneration: An Experimental Study

Background and Objectives: Three-dimensional (3D) metallic trabecular structures made by additive manufacturing (AM) technologies promote new bone formation and osteointegration. Surface modifications by chemical treatments can improve the osteoconductive properties of metallic structures. An in vivo study in sheep was conducted to assess the bone response to randomized trabecular titanium structures that underwent a surface modification by chemical treatment compared to the bone response to the untreated specimens. Material and Methods: Sixteen specimens with a randomized trabecular titanium structure were implanted in the spongious bone of the distal femur and proximal tibia and the cortical bone of the tibial diaphysis of two sheep. Of them, eight implants had undergone a chemical treatment (treated) and were compared to eight implants with the same structure but native surfaces (native). The sheep were sacrificed at 6 weeks. Surface features of the lattice structures (native and treated) were analyzed using a 3D non-contact profilometer. Compression tests of 18 lattice cubes were performed to investigate the mechanical properties of the two structures. Excellent biocompatibility for the trabecular structures was demonstrated in vitro using a cell mouse fibroblast culture. Histomorphometric analysis was performed to evaluate bone implant contact and bone ingrowth. Results: A compression test of lattice cubic specimens revealed a comparable maximum compressive strength value between the two tested groups (5099 N for native surfaces; 5558 N for treated surfaces; p > 0.05). Compared to native surfaces, a homogenous formation of micropores was observed on the surface of most trabeculae that increased the surface roughness of the treated specimens (4.3 versus 3.2 µm). The cellular viability of cells seeded on three-dimensional structure surfaces increased over time compared to that on plastic surfaces. The histomorphometric data revealed a similar behavior and response in spongious and cortical bone formation. The percentage of the implant surface in direct contact with the regenerated bone matrix (BIC) was not significantly different between the two groups either in the spongious bone (BIC: 27% for treated specimens versus 30% for native samples) or in the cortical bone (BIC: 75% for treated specimens versus 77% for native samples). Conclusions: The results of this study reveal rapid osseointegration and excellent biocompatibility for the trabecular structure regardless of surface treatment using AM technologies. The application of implant surfaces can be optimized to achieve a strong press-fit and stability, overcoming the demand for additional chemical surface treatments

Reliability of forced internal rotation and active internal rotation to assess lateral instability of the biceps pulley

Purpose: the aim of this study was to investigate the relationship between positive painful forced internal rotation (FIR) and lateral pulley instability in the presence of a pre-diagnosed posterosuperior cuff tear. The same investigation was conducted for painful active internal rotation (AIR). Methods: a multicenter prospective study was conducted in a series of patients scheduled to undergo arthroscopic posterosuperior cuff repair. Pain was assessed using a visual analog scale (VAS) and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) was administered. The VAS score at rest, DASH score, and presence/absence of pain on FIR and AIR were recorded and their relationships with lesions of the lateral pulley, cuff tear patterns and shape of lesions were analyzed. Results: the study population consisted of 115 patients (mean age: 55.1 years) recruited from 12 centers. The dominant arm was affected in 72 cases (62.6%). The average anteroposterior extension of the lesion was 1.61 cm. The mean preoperative VAS and DASH scores were 6.1 and 41.8, respectively. FIR and AIR were positive in 94 (81.7%) and 85 (73.9%) cases, respectively. The lateral pulley was compromised in 50 cases (43.4%). Cuff tears were partial articular in 35 patients (30.4%), complete in 61 (53%), and partial bursal in 19 (16.5%). No statistical correlation between positive FIR or AIR and lateral pulley lesions was detected. Positive FIR and AIR were statistically associated with complete lesions. Negative FIR was associated with the presence of partial articular tears. Conclusions: painful FIR in the presence of a postero-superior cuff tear does not indicate lateral pulley instability. When a cuff tear is suspected, positive FIR and AIR are suggestive of full-thickness tear patterns while a negative FIR suggests a partial articular lesion. Level of evidence: level I, validating cohort study with good reference standards

Balancing in Unicompartmental Knee Arthroplasty: Balancing in Flexion or in Extension?

Unicompartmental knee arthroplasty (UKA) is an established procedure for the treatment of predominant single compartmental femorotibial osteoarthritis (OA) or osteonecrosis [...

The role of bone marrow edema on autologous matrix induced chondrogenesis for the treatment of osteochondral lesions of the talus

Category: Ankle, Arthroscopy, Basic Sciences/Biologics Introduction/Purpose: to assess the functional and radiological outcomes after AT-AMIC® (arthroscopic talus autologous matrix induced chondrogenesis) in 2 groups: patients with and without bone marrow edema (BME). Methods: Thirty-seven patients of which 24 without edema (GNE) and 13 with edema (GE) were evaluated. All patients were treated with AT-AMIC® repair for osteochondral talar lesion. MRI and CT-scan evaluations, as well as clinical evaluations measured by the VAS score for pain, AOFAS and SF-12 were performed preoperatively (T0) and at 6 (T1), 12 (T2), and 24 (T3) months postoperatively. Results: GNE consisted of 24 patients while GE consisted of 13 patients. In both groups we found a significant difference for clinical and radiological parameters with ANOVA for repeated measures through four time points(p<0.001). In GNE, AOFAS improved significantly at each follow-up(p<0.05); while CT and MRI showed a significant decrease between T1 and T2 and T2 and T3(p<0.05). In GE, AOFAS improved significantly between T0 and T1 and T2 and T3(p<0.05); CT decreased between T1 and T2(p<0.05), while MRI showed a reduction at each follow-up(p<0.05). Lesion size was significantly higher both in MRI and CT in GE in respect to GNE(p<0.05). In the GNE no patients presented edema at T3, while in GE only 23.08% of the patients presented edema at T3. Conclusion: The study revealed that osteochondral lesions of the talus were characterized by bigger size both in MRI and CT in patients with edema. We conclude that AT-AMIC® can be considered a safe and reliable procedure that allows effective healing, regardless of edema and more than half of patients did not present edema six months after surgery

Arthroscopic autologous-matrix induced chondrogenesis in association with microfractures and autologous bone graft for the treatment of osteochondral talar lesions in young patients

Category: Ankle, Ankle Arthritis, Arthroscopy, Basic Sciences/Biologics Introduction/Purpose: The purpose is to evaluate the clinical and radiological outcomes of patients younger than 20 years, treated with the arthroscopic-talus autogolous matrix-induced chondrogenesis (AT-AMIC®) technique and autologous bone graft for osteochondral lesion of the talus (OLT) at a follow-up of 24 months. Methods: 13 patients under 20 years (range 13.2 – 19.85) underwent the AT-AMIC® procedure and autologous bone graft for OLTs. Patients were evaluated pre-operatively (T0) and at 6 (T1), 12 (T2) and 24 (T3) months postoperatively, using the AOFAS score, the VAS and the SF-12 respectively in its Mental (MCS) and Physical component (PCS). Radiological assessment included CT-scan, MRI and intraoperative measurement of the lesion. A multivariate statistical analysis was performed. Results: Mean size lesion measured during surgery was 1.1102 cm3 ± 0.518 cm3. We found a significant difference in clinical and radiological parameters with ANOVA for repeated measures (p<0.001). All clinical scores significantly improved (p<0.05) from T0 to T3. Lesion area significantly reduced from 120.12 ± 29.58 mm2 pre-operatively to 75.78 ± 15.00 mm2 (p<0.05) at final follow- up as assessed by CT, and from 133.32 ± 32.42 mm2 to 83.45 ± 15.54 mm2 (p<0.05) as assessed by MRI. Moreover we noted an important correlation between intra-operative size measurement of the lesion and BMI (p=0.0114). Conclusion: The technique can be considered safe and effective, reporting early good results in young patients. Moreover we demonstrated a significant correlation between BMI and lesion size and a significant impact of OLTs on quality of life

Scientific Production and total ankle arthroplasty

Category: Ankle Arthritis Introduction/Purpose: The purpose of this systematic review was to report clinical outcomes on total ankle replacement (TAR) whose data were extracted from national registers. Methods: A systematic review of the literature, to identify all studies reporting outcomes after total ankle replacement, was performed. Two independent investigators performed the research using MEDLINE, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Embase and Cochrane Databases (1950 to December 2017). Results: Analysis of the literature included 18 articles from 2007 to 2017. Of these 5 articles performed a comprehensive analysis of the national registers, 5 articles evaluated complications and reasons of failure after TAR, 6 articles made a specific outcome register analysis, one article compared TAR and ankle arthrodesis while the last one analysed the role of TAR in patients with rheumatoid arthritis. Conclusion: Scientific publications extracted from national joint registers for total ankle replacement provide useful but heterogeneous information on implants survivorship, implant models and risk factors. There is still a discrepancy between the data reported by designers in clinical studies and the data reported by the registries. The centralization of registers in specialized hospitals with dedicated surgeons, the use of patient reported outcomes (PROMs) in association with surgeon assessments and periodical publications can improve the development of registries and consequently of the literature in this regard

MaioRegen Osteochondral Substitute for the Treatment of Knee Defects: A Systematic Review of the Literature

Background: This study aims to investigate the clinical and radiological efficacy of three-dimensional acellular scaffolds (MaioRegen) in restoring osteochondral knee defects. Methods: MEDLINE, Scopus, CINAHL, Embase, and Cochrane Databases were searched for articles in which patients were treated with MaioRegen for osteochondral knee defects. Results: A total of 471 patients were included in the study (mean age 34.07 ± 5.28 years). The treatment involved 500 lesions divided as follows: 202 (40.4%) medial femoral condyles, 107 (21.4%) lateral femoral condyles, 28 (5.6%) tibial plateaus, 46 (9.2%) trochleas, 74 (14.8%) patellas, and 43 (8.6%) unspecified femoral condyles. Mean lesion size was 3.6 ± 0.85 cm2. Only four studies reported a follow-up longer than 24 months. Significant clinical improvement has been reported in almost all studies with further improvement up to 5 years after surgery. A total of 59 complications were reported of which 52 (11.1%) experienced minor complications and 7 (1.48%) major complications. A total of 16 (3.39%) failures were reported. Conclusion: This systematic review describes the current available evidence for the treatment of osteochondral knee defects with MaioRegen Osteochondral substitute reporting promising satisfactory and reliable results at mid-term follow-up. A low rate of complications and failure was reported, confirming the safety of this scaffold. Considering the low level of evidence of the study included in the review, this data does not support the superiority of the Maioregen in terms of clinical improvement at follow-up compared to conservative treatment or other cartilage techniques

No difference in Oxford Knee Score between medial and lateral unicompartmental knee arthroplasty after two years of follow‐up: a clinical trial

Abstract Purpose In patients with monocompartmental knee osteoarthritis, unicompartmental knee arthroplasty (UKA) can be performed. This study compared the medial versus lateral UKA in patients with monocompartimental knee arthroplasty. It was hypothesised that both implants achieve a similar outcome in OKS. Methods The UKAs were fixed‐bearing medial PPK (Zimmer‐Biomet, Warsaw, Indiana, USA) and fixed‐bearing lateral Zuk (Lima Corporate, Udine, Italy). An intraarticular drain was placed and removed on the first postoperative day. Enoxaparin sodium 4000 units subcutaneously daily for 45 days was used as thromboembolic prophylaxis. The Italian version of the OKS was used for the clinical assessment. The following complications were also recorded: anterior knee pain, infection and revision surgeries. Results Data from 203 patients were collected. The mean age of the patients was 68.9 ± 6.7 years and the mean BMI was 28.1 ± 4.1 kg/m2. The mean OKS on admission was 22.1 ± 4.5 points. On admission, women, patients older than 70 years, and those with a BMI lower than 28 kg/m2 who underwent lateral UKA evidenced lower OKS. At the last follow‐up, 26.7 and 26.9 months for the lateral and medial UKA, respectively, no between groups difference in OKS was evidenced. No patients experienced complications. Conclusion Medial and lateral UKA achieve similar outcomes in OKS at a minimum of two years of follow‐up