Failure rate of isolated medial meniscus repair in the stable knee: Systematic review and meta-analysis.

PURPOSE: The present meta-analysis aims to determine the outcomes and failure rates for medial meniscus repairs in patients with stable knees. METHODS: A literature search was conducted using PubMed and Scopus with the terms '(medial meniscus OR medial meniscal) AND (repair)'. The search strategy was based on the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) protocol and included 93 articles assessed for eligibility. The search criteria were limited to studies reporting outcomes and failure rates. The exclusion criteria included languages other than English, biomechanical studies, letters to editors, non-full text, review articles, meta-analyses and case reports. RESULTS: In total, 10 studies with 595 patients were included. Degenerative tears or studies reporting meniscus repair outcomes on root repairs, revision or primary anterior cruciate ligament reconstruction, discoid menisci or ramp lesions were excluded. All studies included revision surgery and/or clinical symptoms as failure definitions. The overall medial meniscal repair failure rate was 26% with a 95% confidence interval (CI) [15%-37%]. The mean time to failure from isolated medial meniscus repair surgery was 27.7 months with 95% CI [18.5-36.9 months]. The postoperative Lysholm and IKDC scores were reported in three articles. At the final follow-up, the mean postoperative Lysholm and IKDC scores were 92.3 with 95% CI [84.5-100] and 88.6 with 95% CI [83.5-93.8], respectively. CONCLUSION: The current meta-analysis revealed an overall failure rate of 26% in the case of medial meniscus repair in a stable knee. For these reasons, the patient should be aware of the substantial risk of revision surgery (one out of four cases). Medial meniscus repair in a stable knee yielded good clinical results. LEVEL OF EVIDENCE: II.

Ten-year outcomes of anterior cruciate ligament reconstruction with hamstring tendon autograft and femoral fixation with a cortico-cancellous screw suspension device.

PURPOSE: To evaluate the clinical and radiographic outcomes of anterior cruciate (ACL) reconstruction at minimum 10-year follow-up. METHODS: Ninety-three patients who underwent primary unilateral ACL reconstruction with hamstring tendon autograft, transtibial technique and femoral cortico-cancellous screw suspension device (Athrax, Leader Medica s.r.l) between 2010 and 2012 were retrospectively reviewed. Mean follow-up was 136 months. Evaluation was performed using the International Knee Documentation Committee score (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Lysholm Knee Score and Tegner Activity Level Scale. Incidence of OA was determined by comparing standard anteroposterior and lateral weightbearing radiographs of the ACL-reconstructed and contralateral knee. Osteoarthritis severity was graded according to the Kellgren-Lawrence (KL) score. RESULTS: Median Tegner activity level was 6 (5-7). Lysholm and IKDC scores were 100 (95-100) and 90 (86-95), respectively, KOOS was 98 (95-100). Of ACL-reconstructed knees, 41 (50%) had radiographic OA, of which 6 (7.3%) had severe OA (KL III). Of the contralateral healthy knees, 28 (34.1%) had radiographic evidence of OA. Of these 22 (26.8%) and 6 (7.3%) patients had, respectively, KL-I and KL-II. 11 patients (11.8%) underwent subsequent knee surgery: 5 (5.4%) revisions, 3 (3.2%) meniscal surgeries, 2 (2.2%) other surgeries, 1 (1.1%) contralateral ACL reconstruction. CONCLUSIONS: The study demonstrates that ACL reconstruction with HT autograft and cortico-cancellous screw suspension device determines satisfying clinical results after 10 years of follow-up. From our cohort, a low rate of graft failure has been reported, even though almost 50% of patients present a knee OA greater or equal to grade II KL.

Cannulated screws fixation for nondisplaced femoral neck fractures: early versus late weight-bearing-a prospective analysis.

PURPOSE: Nondisplaced intracapsular fractures (Garden I/II) are predominantly treated with an internal fixation technique. The purpose of the study is to identify the best rehabilitation protocol after internal fixation with 3 parallel cannulated screws. METHODS: All patients operated on from 2016 to 2021 for femoral neck fractures by internal fixation with 3 cannulated screws were enrolled into this prospective study. The population was divided into two groups: Group A (n = 34) who followed a postoperative rehabilitation protocol involving full and immediate loading, and Group B (n = 22) who followed a postoperative rehabilitation protocol involving late full loading (after 30 days). The two groups were compared with each other by mortality rate, postoperative complications and need for re-interventions. Functional outcome and quality of life were assessed at the minimum follow-up of 1 year using the modified Harris Hip Score (HHS) and the Short form health survey (SF-12) questionnaire. RESULTS: Group A showed a lower complication rate (2.9% vs. 18.2%), a lower 1-year mortality rate (5.9% vs. 9.1%), a better perception of mental health status (SF12-MCS 56.2 vs. 51.4, p = 0.03) but a worse perception of one's physical health status (SF12-PCS 48.1 vs. 56.7, p < 0.01). The two groups were also statistically overlapping in terms of the functional outcome achieved after the intervention (HHS was 90.94 in Group A vs. 93.15 in Group B, p = 0.32). CONCLUSION: Postoperative complications, mortality and revision rate were higher in patients who followed a late-loaded rather than early loaded rehabilitation protocol. Functional outcome at 1-year survival is not significantly different. In nondisplaced intracapsular hip fractures treated with cannulated screws, an immediate full load should be preferred. Query.

Metal-backed or all-poly tibial components: which are better for medial unicompartmental knee arthroplasty? A propensity-score-matching retrospective study at the 5-year follow-up.

BACKGROUND: This retrospective medium-term follow-up study compares the outcomes of medial fixed-bearing unicompartmental knee arthroplasty (mUKA) using a cemented metal-backed (MB) or an all-polyethylene (AP) tibial component. MATERIALS AND METHODS: The database of our institution was mined for primary mUKA patients implanted with an MB or an AP tibial component (the MB-UKA and AP-UKA groups, respectively) from 2015 to 2018. We compared patient demographics, patient-reported outcome measures (PROMs), and motion analysis data obtained with the Riablo™ system (CoRehab, Trento, Italy). We conducted propensity-score-matching (PSM) analysis (1:1) using multiple variables. RESULTS: PSM analysis yielded 77 pairs of MB-UKA and AP-UKA patients. At 5 years, the physical component summary (PCS) score was 52.4 ± 8.3 in MB-UKA and 48.2 ± 8.3 in AP-UKA patients (p < 0.001). The Forgotten Joint Score (FJS-12) was 82.9 ± 18.8 in MB-UKAs and 73.4 ± 22.5 in AP-UKAs (p = 0.015). Tibial pain was reported by 7.8% of the MB-UKA and 35.1% of the AP-UKA patients (p < 0.001). Static postural sway was, respectively, 3.9 ± 2.1 cm and 5.4 ± 2.3 (p = 0.0002), and gait symmetry was, respectively, 92.7% ± 3.7 cm and 90.4% ± 5.4 cm (p = 0.006). Patient satisfaction was 9.2 ± 0.8 in the MB-UKA and 8.3 ± 2.0 in the AP-UKA group (p < 0.003). CONCLUSIONS: MB-UKA patients experienced significantly better 5-year static sway and gait symmetry outcomes than AP-UKA patients. Although the PROMs of the two groups overlapped, MB-UKA patients had a lower incidence of tibial pain, better FJS-12 and PCS scores, and were more satisfied.

Ulnar nerve anteposition with adipofascial flap, an alternative treatment for severe cubital syndrome.

BACKGROUND: Ulnar nerve entrapment at the elbow is the second most common cause of nerve entrapment in the upper limb. Surgical techniques mainly include simple decompression, decompression with anterior transposition and medial epicondylectomy. METHODS: We performed decompression with anterior transposition and protected ulnar nerve by adipofascial flap (a random flap with radial based vascularization, harvested through the avascular plane of Scarpa's fascia. We analyzed patients who underwent ulnar nerve ante-position from 2015 to 2022 according to inclusion and exclusion criteria for a total of 57 patients. All patients included were graded on the McGowan's classification Messina criteria and the British Medical Research Council modified by Mackinnon and Dellon. RESULTS: The average McGowan's score was 2.4 (± 0.6), Messina's criteria 91.2% indicated a satisfactory or excellent result, sensibility at 6 months was 98.5% S3 or more. A preferential technique has not yet been defined. CONCLUSIONS: The adipofascial flap offers numerous advantages in providing a pliable, vascular fat envelope, which mimics the natural fatty environment of peripheral nerves and creates favorable micro-environmental conditions to contribute to neural regeneration via axon outgrowth.

Synovial Biomarkers to Detect Chronic Periprosthetic Joint Infection: A Pilot Study to Compare Calprotectin Rapid Test, Calprotectin ELISA Immunoassay and Leukocyte Esterase Test.

BACKGROUND: Periprosthetic joint infection (PJI) is a devastating complication after joint replacement surgery, and making diagnosis is often far from obvious. Calprotectin was recently proposed as a promising synovial biomarker to detect PJI. To our knowledge, no comparative study exists between enzyme-linked immunosorbent assay (ELISA) and rapid calprotectin test (CalFAST). Our purpose was to compare these methods with leukocyte esterase (LE) test from synovial fluid of painful knee arthroplasty subjected to infectious workup. METHODS: Ninety-three patients were included in this prospective observational study. They underwent synovial fluid aspiration that was analyzed for cell count, microbiological culture, LE test, calprotectin rapid test, and calprotectin immunoassay dosage. The 2018 Consensus Statements criteria for PJI were used to diagnose PJI. Sensitivity, specificity, positive and negative likelihood ratio, and receiver operating characteristic were calculated for detection methods and compared. RESULTS: We categorized 39 patients as infected and 50 patients as not infected. The sensitivity comparing the ELISA test and CalFAST test was similar, 92.3% and 97.4%, respectively. LE rapid test showed 46% of sensitivity and 94% of specificity. The highest specificity was found with ELISA test (100%). Comparing the receiver operating characteristic curves by z-test, there were statistically significant differences between LE strip test and the other two methods. Otherwise, no statistically significant differences were present between ELISA and CalFAST test. CONCLUSION: Synovial calprotectin detection has high accuracy in knee PJI diagnosis, both ELISA and rapid test. LE strip test remains a good test to confirm the diagnosis of PJI in case of positivity. In clinical practice, the calprotectin rapid test can be considered an excellent point-of-care test.

Comparison of Three 3D Segmentation Software Tools for Hip Surgical Planning.

In hip arthroplasty, preoperative planning is fundamental to reaching a successful surgery. Nowadays, several software tools for computed tomography (CT) image processing are available. However, research studies comparing segmentation tools for hip surgery planning for patients affected by osteoarthritic diseases or osteoporotic fractures are still lacking. The present work compares three different software from the geometric, dimensional, and usability perspectives to identify the best three-dimensional (3D) modelling tool for the reconstruction of pathological femoral heads. Syngo.via Frontier (by Siemens Healthcare) is a medical image reading and post-processing software that allows low-skilled operators to produce prototypes. Materialise (by Mimics) is a commercial medical modelling software. 3D Slicer (by slicer.org) is an open-source development platform used in medical and biomedical fields. The 3D models reconstructed starting from the in vivo CT images of the pathological femoral head are compared with the geometries obtained from the laser scan of the in vitro bony specimens. The results show that Mimics and 3D Slicer are better for dimensional and geometric accuracy in the 3D reconstruction, while syngo.via Frontier is the easiest to use in the hospital setting.

Suture anchor reinsertions of distal biceps rupture: a histologic analysis of a torn tendon and clinical results at short- and long-term follow-up.

BACKGROUND: Distal biceps brachii tendon (DBBT) rupture is a relatively rare injury. Nonsurgical treatment determines 30%-40% power loss of elbow flexion and up to 50% of forearm supination. Therefore, refixation of the DBBT is recommended. The DBBT is exposed to tension and compression loading. It is known that the tendon under compression might develop fibrocartilaginous metaplasia that improves the resistance to compression but reduces the resistance to tension. To test this hypothesis, the present study evaluated the presence of cartilage in DBBT samples. Furthermore, the present study evaluated the clinical and functional outcomes of anatomic reinsertion through suture anchors in a cohort of patients after 1, 3, and 5 years of follow-up. METHODS: Between 2011 and 2014, 21 patients with DBBT tear underwent a suture anchor reattachment. Histochemical and immunohistochemical analysis of torn samples of DBBT collected at the time of surgical repair were performed to test the presence of cartilage. During the follow-up examination, mobility, elbow radiographs, Mayo Elbow Performance Score, and isokinetic analysis were prospectively evaluated. RESULTS: Fibrocartilage was detected in all tendon samples collected. Two cases of transient paresthesia in the lateral antebrachial cutaneous nerve occurred, but they resolved in 6 weeks. There were no vascular deficits, re-ruptures, radioulnar synostoses, or infective complications at follow-up. Three patients reported loss of supination. Mayo Elbow Performance Score showed good and excellent clinical and functional results. No significant differences about strength and fatigue in flexion-supination were recorded between the surgical and contralateral side at 3 and 5 years of follow-up. Arm dominance influenced supination but not flexion. CONCLUSION: On the basis of our results, we find that the presence of cartilage metaplasia might make the DBBT at higher risk of rupture assuming the compression loading and the hypovascular zone of the tendon. However, concerning the lack of histologic analysis of the healthy DBBT, its role in tendon pathology remains to be clearly defined. The technique of suture anchor reinsertion by a single incision was shown to be safe, with few complications and good functional results at 5 years of follow-up. No significant differences were reported between the injured and noninjured side in terms of flexion and supination isokinetic analysis, whereas arm dominance had a positive effect on supination.

The use of intra-articular injection of autologous micro-fragmented adipose tissue as pain treatment for ankle osteoarthritis: a prospective not randomized clinical study.

PURPOSE: The objective of this study was to evaluate the safety and the efficacy of intra-articular injections of autologous micro-fragmented adipose tissue in patients affected by early or moderate ankle osteoarthritis (AOA). METHODS: A total of 31 symptomatic patients, aged 28-71 years, affected by AOA, were treated with 5 ml of autologous micro-fragmented adipose tissue. Clinical evaluations before the treatment and after six, 12, and 24 months were performed through American Orthopaedic Foot and Ankle Society (AOFAS) scale, the Foot and Ankle Disability Index (FADI), and Visual Analogue Scale (VAS) scores. Adverse events were recorded. RESULTS: No severe complications were noted during the treatment and the follow-up period. A statistically significant improvement from basal evaluation to the six, 12-, and 24-month follow-up visit was observed, whereas a statistically significant worsening from the 12-month to the 24-month follow-up visit was showed. CONCLUSION: The autologous micro-fragmented adipose tissue for the treatment of pain in ankle osteoarthritis seems safe and able to provide positive clinical outcomes, potentially offering a new minimally invasive therapeutic option for patients who are not eligible for more invasive approaches. Further high-quality studies are needed to confirm these findings.

Stem Cells in Autologous Microfragmented Adipose Tissue: Current Perspectives in Osteoarthritis Disease.

Osteoarthritis (OA) is a chronic debilitating disorder causing pain and gradual degeneration of weight-bearing joints with detrimental effects on cartilage volume as well as cartilage damage, generating inflammation in the joint structure. The etiology of OA is multifactorial. Currently, therapies are mainly addressing the physical and occupational aspects of osteoarthritis using pharmacologic pain treatment and/or surgery to manage the symptomatology of the disease with no specific regard to disease progression or prevention. Herein, we highlight alternative therapeutics for OA specifically considering innovative and encouraging translational methods with the use of adipose mesenchymal stem cells.

K-wire fixation vs 23-gauge percutaneous hand- crossed hypodermic needle for the treatment of distal phalangeal fractures.

BACKGROUND: Distal Phalanx (DP) fractures are the most common hand injuries. Bone fixation associated with soft tissue reconstruction, is often required to ensure more effective outcomes. The aim of the present study is to compare functional outcomes of DP fractures surgically treated with crossed manual drilled 23 Gauge needles vs crossed Kirschner-wires (k-wire). METHODS: Clinical data included analysis of patient demographics, range of motion (ROM), and complications. Radiographic assessment considered fracture type, location, fracture displacement, and radiographic union. Functional outcomes analysis was performed.The statistical significance was assessed at the level of probability lower than 5%. RESULTS: A total of 60 patients from 2012 to 2015 were retrospectively enrolled and among them 12 patients suffering from diabetes or current smokers. A total of 60 DP fractures were treated, 32 with needles (group A) and 28 with k-wire fixation (group B). Time to union, showed in different time points, was significantly lower in group A (≤ 40 days, p = 0.023*) compared to group B. ROM of the distal interphalangeal joint at six months follow-up was 60° in group A and 40° in group B. A significant improvement was observed (p = 0.001*) in the 23 G needle treated group. Functional outcome analysis showed that VAS was significantly lower in group A compared to group B (p = 0.023*). CONCLUSION: Our study showed that the 23 G needle yielded satisfactory results in terms of time to union and range of motion compared to k-wire fixation especially for tuft and shaft DP fractures. Therefore, should be a valid alternative to k-wire fixation in selected patients.

Synovial Fluid Calprotectin for the Preoperative Diagnosis of Chronic Periprosthetic Joint Infection.

BACKGROUND: The diagnosis of periprosthetic joint infection (PJI) represents a challenge in clinical practice and the analysis of synovial fluid is a useful diagnostic tool. Calprotectin is an inflammatory biomarker widely used in the evaluation of chronic inflammatory diseases; however, little is known about its role in PJI. The purpose of this study is to determine the reliability of synovial calprotectin in the diagnosis of PJI. METHODS: Seventy-six patients with painful knee arthroplasty were included in this prospective observational study. Synovial fluid was analyzed for cell count, percentage of polymorphonuclear neutrophils, microbiological culture, leukocyte esterase strip test, alpha-defensin rapid test, and calprotectin immunoassay dosage. The 2018 Consensus Statements criteria for PJI were used as standard reference to define the presence of infection. Sensitivity, specificity, positive and negative likelihood ratio, and receiver-operation characteristic curve were calculated for calprotectin immunoassay test. RESULTS: By 2018 Consensus Statements criteria for PJI, 28 patients were considered infected, 44 patients were considered not infected, and 4 patients were classified as inconclusive. The calprotectin synovial fluid test resulted in 2 false-positive results and no false-negative results. The calprotectin synovial fluid test demonstrated a sensitivity of 100% (95% confidence interval [CI] 99.96-100) and specificity of 95% (95% CI 89.4-100) for the diagnosis of PJI. The positive likelihood ratio was 22 (95% CI 5.680-85.209) and the negative likelihood ratio was 0 (95% CI 0-0.292). The area under the receiver-operation characteristic curve was 0.996 (95% CI 94.3-100). CONCLUSION: The present study suggests that synovial calprotectin immunoassay test has a high sensitivity and specificity in the diagnosis of knee PJI. Moreover, it is easily applied, quick and valuable in clinical practice.

Treatment of avascular osteonecrosis of femoral head by core decompression and platelet-rich plasma: a prospective not controlled study.

PURPOSE: Core decompression is a surgical option since the 1960s for hip osteonecrosis treatment. This technique promotes bone repair by reducing intramedullary pressure, but this is not often enough to stop the progression of necrosis. The aim of this study was to associate core decompression with the regenerative stimulus provided by platelet-rich plasma (PRP) and compare our results with other regenerative techniques. METHODS: Femoral head osteonecrosis was prospectively evaluated in 30 hips (22 patients, 15-60 years) treated by core decompression and PRP graft. Patients presented monolateral or bilateral osteonecrosis in stage I-IIA-IIB according to Arlet and Ficat classification. The outcome was assessed by changes in Harris Hip Score (HHS) and the need for total hip replacement (THA). RESULTS: The mean preoperative HHS was 64 points, at two years from surgery was roughly 84 points. Sixteen of 30 hips showed osteonecrosis progression of the femoral head and were converted to THA. At the five year follow-up, the survival rate was 100% for patients at stage I, 67% for stage IIA, and 0% for stage IIB and was 68% and 32% for idiopathic and secondary osteonecrosis, respectively. CONCLUSION: Core decompression combined with PRP could be indicated as a treatment for the I and IIA stages of osteonecrosis, as it significantly reduces joint pain and delays THA. This procedure should be avoided in AVNFH related to cortisone therapy because only a few benefits have been proven. It also has the advantage of being technically simple, minimally invasive, and free from complications.

Percutaneous k-wire leverage reduction and retrograde transphyseal k-wire fixation of angulated radial neck fractures in children.

PURPOSE: To describe clinical and radiographic outcomes after surgical management of angulated radial neck fracture in children. METHODS: Twenty children (aged 2-11 years) with angulated radial neck fracture with more than 30° angulations (Judet type III and IV fractures) were retrospectively reviewed. All the enrolled patients were surgically treated with percutaneous k-wire leverage reduction and retrograde transphyseal k-wire fixation. Clinical outcomes were evaluated using Tibone and Stoltz score and the Mayo Elbow Performance Score (MEPS). Radiographic outcomes were evaluated with Métaizeau score. Complications were also evaluated. RESULTS: At a mean follow-up of 20 months, no patients showed axial deformity of the upper limb or instability of the elbow. The mean value of the MEPS was 99.2, and excellent clinical results were achieved in 14 patients (73.7%) at Tibone and Stoltz score. The final X-rays showed fracture healing in all patients; furthermore, 75% of patients showed excellent reduction at Métaizeau score. No patient developed complication. There were no iatrogenic nerve injuries or pin infections. CONCLUSIONS: The results demonstrate that percutaneous k-wire leverage reduction and retrograde transphyseal k-wire fixation of angulated radial neck fracture treatment is a simple, effective, rapid and inexpensive procedure. LEVEL OF EVIDENCE: IV (case series and systematic review of level IV studies).

Synovium-derived stromal cell-induced osteoclastogenesis: a potential osteoarthritis trigger.

Purpose: To shed light on the idea that mesenchymal stem/stromal cells (MSCs) recruited in synovium (SM) (i.e. Synovium-Derived Stromal Cells, SDSCs) could be involved in Osteoarthritis (OA) pathophysiology. Attention was also paid to a further stromal cell type with a peculiar ultrastructure called telocytes (TCs), whose role is far from clarified. Methods: In the present in vitro study, we compared SDSCs isolated from healthy and OA subjects in terms of phenotype, morphology and differentiation potential as well as in their capability to activate normal Peripheral Blood Mononuclear Cells (PBMCs). Histological, immunohistochemical and ultrastructural analyses were integrated by qRT-PCR and functional resorbing assays. Results: Our data demonstrated that both SDSC populations stimulated the formation of osteoclasts from PBMCs: the osteoclast-like cells generated by healthy-SDSCs via transwell co-cultures were inactive, while OA-derived SDSCs have a much greater effectiveness. Moreover, the presence of TCs was more evident in cultures obtained from OA subjects and suggests a possible involvement of these cells in OA. Conclusions: Osteoclastogenic differentiation capability of PBMCs from OA subjects, also induced by B synoviocytes has been already documented. Here we hypothesized that SDSCs, generally considered for their regenerative potential in cartilage lesions, have also a role in the onset/maintenance of OA. Clinical relevance: Our observations may represent an interesting opportunity for the development of a holistic approach for OA treatment, that considers the multifaceted capability of MSCs in relation to the environment.

Treatment of complex foot deformities with hexapod external fixator in growing children and young adult patients.

BACKGROUND: Treatment of complex foot deformities in growing children and young adult patients is challenging. The traditional approach consists of extensive soft tissues releases, osteotomies and/or arthrodesis. More recently, distraction osteogenesis has been proposed as an alternative strategy. The aim of this study was to describe our treatment strategy and report clinical outcomes of the patients affected from complex foot deformities treated by distraction osteogenesis and hexapod external fixator. MATERIALS AND METHODS: We retrospectively reviewed 10 consecutive patients with complex foot and ankle deformities treated from 2014 to 2016 at our unit. A TrueLok external fixator system was used in all patients. Final outcome was classified as good, fair and poor according to the criteria indicated by Paley and Ferreira. The results were also evaluated by the pre-operative and post operative American Orthopedic Foot and Ankle Score (AOFAS) and The Manchester-Oxford Foot Questionnaire (MOXFQ). RESULTS: A plantigrade foot was obtained in eight patients at the end of treatment, while in two patients a recurrence of the deformity was noted. Result was classified as good in 6 patients, fair in 2 patients, and poor in 2 patients. The AOFAS score improved from 33.9±21.2 pre-operatively to 67.25±15.1 post-operatively (p=0.005). A statistically significant improvement was observed for the MOXFQ score as well (from 60.6±23.3 to 33.0±25.2, p=0.020). CONCLUSIONS: Our study shows that the TrueLok hexapod external fixator is a safe and effective tool in treatment of complex rigid foot deformities. Nevertheless, deformity recurrence can be observed in some cases and treatment remains challenging. Distraction osteogenesis should be reserved as a salvage solution for particularly complex cases and should be performed at dedicated specialized centers.

Fibrocartilaginous metaplasia identified in the long head of the biceps brachii.

BACKGROUND: In the glenohumeral joint, the long head of biceps brachii (LHBB) is exposed to tension and compression loading. The short head of biceps brachii (SHBB) works only in tension. It is known that tendon under compression might develop fibrocartilaginous metaplasia that improves the resistance to compression but reduces the resistance to tension. This study evaluated the presence of cartilage in LHBB and SHBB samples, supporting its possible role in tendon tear. METHODS: Between 2014 and 2016, 13 samples of LHBB and SHBB were collected during surgery for shoulder instability, glenohumeral arthritis, and massive rotator cuff tears. The samples were stained with hematoxylin and eosin, safranin-O, and Alcian blue (pH 1.0) for light microscopy. Immunohistochemistry was performed using anti-S100, anti-collagen I and II, and anti-tenascin-C antibodies. RESULTS: Histochemistry: LHBB samples showed matrix disorganization, with clusters of chondrocyte surrounded by collagen fibers and glycosaminoglycans. Safranin-O showed evident metachromasia. SHBB samples did not show any matrix disorganization or cartilaginous metaplasia. Immunohistochemistry: In all LHBB samples, anti-S100 and anti-collagen II showed cartilage in proximity of the tendon tear. Tenascin C immunostained closely to the disorganized matrix areas. SHBB, however, showed no positive areas for S-100, anti-collagen II, or tenascin C. CONCLUSIONS: According to our results, we hypothesize that the repeated stimulation in compression may induce the formation of fibrous cartilage. However, to date its role in tendon pathology remains to be clearly defined.

Superior capsular reconstruction of the shoulder: the ABC (Arthroscopic Biceps Chillemi) technique.

Superior capsular reconstruction (SCR) demonstrated its efficacy as a treatment option available in patients affected with irreparable posterosuperior rotator cuff tears without any signs of arthritis. Originally, the fascia lata autograft was fixed medially to the glenoid (with two or more anchors) and laterally to the greater tuberosity (with a compression double-row technique using four anchors or three transosseous tunnels). Additionally, side-to-side sutures were used to anteriorly and posteriorly connect the graft to the native residual rotator cuff tissue. However, the fascia lata as an autograft has a disadvantage related to the donor-site morbidity. To solve this aspect, allografts were employed with initial promising results. Nowadays, SCR is to be considered a technically demanding and expensive procedure, because of the cost of the allograft plus that of all the anchors employed to fix it. The Arthroscopic Biceps Chillemi's technique addresses these concerns in performing SCR and presents numerous advantages being a safe, easier, time and cost-saving way compared to the other published techniques. This technique has only one conditio sine qua non: the presence of the long head of the biceps tendon (LHB), used as an autograft. This condition may be interpreted as a disadvantage of this procedure in the presence of some anatomic variations of the intra-articular portion of the LHB and the very rare absence of the tendon or in case of partial or complete rupture of the LHB tendon associated with a rotator cuff tear.

Genipin-Crosslinked Chitosan Gels and Scaffolds for Tissue Engineering and Regeneration of Cartilage and Bone.

The present review article intends to direct attention to the technological advances made since 2009 in the area of genipin-crosslinked chitosan (GEN-chitosan) hydrogels. After a concise introduction on the well recognized characteristics of medical grade chitosan and food grade genipin, the properties of GEN-chitosan obtained with a safe, spontaneous and irreversible chemical reaction, and the quality assessment of the gels are reviewed. The antibacterial activity of GEN-chitosan has been well assessed in the treatment of gastric infections supported by Helicobacter pylori. Therapies based on chitosan alginate crosslinked with genipin include stem cell transplantation, and development of contraction free biomaterials suitable for cartilage engineering. Collagen, gelatin and other proteins have been associated to said hydrogels in view of the regeneration of the cartilage. Viability and proliferation of fibroblasts were impressively enhanced upon addition of poly-l-lysine. The modulation of the osteocytes has been achieved in various ways by applying advanced technologies such as 3D-plotting and electrospinning of biomimetic scaffolds, with optional addition of nano hydroxyapatite to the formulations. A wealth of biotechnological advances and know-how has permitted reaching outstanding results in crucial areas such as cranio-facial surgery, orthopedics and dentistry. It is mandatory to use scaffolds fully characterized in terms of porosity, pore size, swelling, wettability, compressive strength, and degree of acetylation, if the osteogenic differentiation of human mesenchymal stem cells is sought: in fact, the novel characteristics imparted by GEN-chitosan must be simultaneously of physico-chemical and cytological nature. Owing to their high standard, the scientific publications dated 2010-2015 have met the expectations of an interdisciplinary audience.