Early signs of osteoarthritis in differing rat osteochondral defects.

Preclinical models of osteochondral defects (OCDs) are fundamental test beds to evaluate treatment modalities before clinical translation. To increase the rigor and reproducibility of translational science for a robust "go or no-go," we evaluated disease progression and pain phenotypes within the whole joint for two OCD rat models with same defect size (1.5 x 0.8 mm) placed either in the trochlea or medial condyle of femur. Remarkably, we only found subtle transitory changes to gaits of rats with trochlear defect without any discernible effect to allodynia. At 8-weeks post-surgery, anatomical evaluations of joint showed early signs of osteoarthritis with EPIC-microCT. For the trochlear defect, cartilage attenuation was increased in trochlear, medial, and lateral compartments of the femur. For condylar defect, increased cartilage attenuation was isolated to the medial condyle of the femur. Further, the medial ossicle showed signs of deterioration as indicated with decreased bone mineral density and increased bone surface area to volume ratio. Thus, OCD in a weight-bearing region of the femur gave rise to more advanced osteoarthritis phenotype within a unilateral joint compartment. Subchondral bone remodeling was evident in both models without any indication of closure of the articular cartilage surface. We conclude that rat OCD, placed in the trochlear or condylar region of the femur, leads to differing severity of osteoarthritis progression. As found herein, repair of the defect with fibrous tissue and subchondral bone is insufficient to alleviate onset of osteoarthritis. Future therapies using rat OCD model should address joint osteoarthritis in addition to repair itself.

Effects of Preoperative Abnormality of Posterior Tibial Tendon on the Surgical Outcomes of Medial Osteochondral Lesion of the Talus.

BACKGROUND: Although surgical treatment for osteochondral lesion of the talus (OLT) can obtain good clinical outcomes, the rate of return to sports is variable. It is reported that medial OLT unrelated to trauma has abnormal structures in the medial aspect, which may induce the medial OLT due to the medial instability. The posterior tibial tendon (PTT) plays an important role in the stabilization of the foot, and high mechanical stress may be added to the PTT to compensate for medial instability in medial OLT. We investigated whether abnormal PTT findings on preoperative magnetic resonance imaging (MRI) in patients with OLT affect clinical outcomes after surgery.  Methods: Eighty-one ankles in 74 patients who were treated surgically for OLT were included in this study (41 men and 33 women; mean age, 26.0 years). Abnormalities of the PTT were evaluated using preoperative MRI. The Japanese Society for Surgery of the Foot (JSSF) scale, arch height, and ankle activity score (AAS) on standing plain radiogram were compared between patients with and those without preoperative PTT abnormalities. RESULTS: Twenty-five ankles (30.9%) had PTT abnormalities on preoperative MRI. All patients with preoperative PTT abnormalities were medial OLT. There were no significant differences in the preoperative JSSF scale in the procedures for OLT. The postoperative JSSF scale and arch height were significantly lower in patients with preoperative PTT abnormalities than those without them. AAS in patients with preoperative abnormalities significantly decreased at the final follow-up.  Conclusion: PTT abnormalities on preoperative MRI may affect clinical outcomes even in preoperative asymptomatic patients in the medial OLT unrelated to trauma.

Comparative analysis of short-term efficacy between robot-assisted retrograde drilling and arthroscopic microfracture for osteochondral lesions of the talus.

Objective: To investigate the short-term clinical efficacy of robot-assisted retrograde drilling and arthroscopic microfracture for osteochondral lesions of the talus (OCLT). Methods: This study was divided into two groups: experimental group: robot-assisted retrograde drilling group; control group: arthroscopic microfracture group. A total of 6 OCLT patients who were treated with robot navigation-assisted retrograde drilling and 10 OCLT patients who were treated with arthroscopic microfracture between October 2020 and October 2021 were retrospectively analyzed. There were 11 males and five females, with a mean age of 36 years. The patients were followed up for 6-12 months to compare the changes in the OCLT lesion area by magnetic resonance imaging (MRI), visual analogue scale/score (VAS) and American Orthopedic Foot and Ankle Society score (AOFAS) before and after surgery. Results: All 16 patients were followed up for an average of 8 months, and no complications such as joint infection, nerve injury, or active bleeding occurred during the follow-up period. Only one patient suffered discomfort involving transient postoperative pain in the operative area, but did not experience long-term numbness or chronic pain. Postoperative MRI revealed that none of the patients had severe signs of osteonecrosis, osteolysis or cystic changes of the talus, with lesion areas smaller than those before surgery. The difference was statistically significant (P < 0.01). The patients in the experimental group showed a more significant improvement in the last 3 months than in the first 3 months of the follow-up period. At the last follow-up, the VAS score was 3 points in the experimental group and 2.2 points in the control group, and the AOFAS score was 88.6 points in the experimental group and 88 points in the control group, all of which were significantly higher than those before operation, and the differences were statistically significant, but there was no statistically significant difference between the groups. Conclusion: Both robot navigation-assisted retrograde drilling and arthroscopic microfracture for bone marrow stimulation (BMS) to treat OCLT in all patients obtained satisfactory effects in the short term. In addition, the follow-up revealed that with excellent efficacy and few complications, robot navigation-assisted retrograde drilling was safe and minimally invasive, and greatly reduced operative time. Consequently, robot navigation-assisted retrograde drilling for BMS was a safe and effective procedure for the treatment of OCLT.

No difference between 5 and 6 weeks of non-weight bearing after osteochondral grafts for medial osteochondral defects of the talus with medial malleolar osteotomy.

PURPOSE: The present study aimed to compare the clinical outcomes and safety at a 1-year follow-up after 5 or 6 weeks of non-weight bearing after a Talar OsteoPeriostic grafting from the Iliac Crest (TOPIC) for a medial osteochondral lesion of the talus (OLT). METHODS: A retrospective comparative case-control analysis of prospectively followed patients who underwent a TOPIC procedure with medial malleolus osteotomy was performed. Patients were matched in two groups with either 5 or 6 weeks of non-weight bearing. Clinical outcomes were evaluated using the Numeric Rating Scale (NRS) during walking, rest, running, and stairclimbing. Additionally, the Foot and Ankle Outcome Score (FAOS) and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score were assessed. Moreover, radiology and complications were assessed. RESULTS: Eleven patients were included in the 5-week non-weight bearing group and 22 in the 6-week non-weight bearing group. No significant differences were found in any of the baseline variables. The NRS during walking in the 5-week group improved by 3.5 points and 4 points for the 6-week group (p = 0.58 at 1-year post-operatively). In addition, all other NRS scores, FAOS subscales and the AOFAS scores improved (all n.s. at 1 year follow-up). No significant differences in radiological (osteotomy union and cyst presence in the graft) were found. Moreover, no significant differences were found in terms of complications and reoperations. CONCLUSION: No statistical significant differences were found in terms of clinical, radiological and safety outcomes between 5 or 6 weeks of non-weight bearing following a TOPIC for a medial OLT. LEVEL OF EVIDENCE: Level III, Therapeutic.

Medial malleolar osteotomy in the treatment of osteochondral lesions of the Talus - incidence and impact on functional outcome: a retrospective analysis based on data from the German Cartilage Register (KnorpelRegister DGOU).

BACKGROUND: There has long been discussion regarding the impact of medial malleolar osteotomies (MMO) as an adjunctive treatment for osteochondral lesions of the talus (OCLT). MMO may improve the visibility and accessibility of the talus, but they also pose a risk of periprocedural morbidity. There is a lack of research about the prevalence and consequences of MMO in the surgical treatment of OCLT. METHODS: This study retrospectively evaluated data from the German Cartilage Register (KnorpelRegister DGOU) from its implementation in 2015 to December 2020. The impact of MMO on patient-reported outcome measures (PROMs) was investigated. Wherever possible, subgroups were built and matched using a propensity score which matched a group undergoing OCLT without MMO. Matching included age, sex, weight, localization of the OCLT, the international cartilage repair society (ICRS) grading, surgical procedure and preoperative symptoms using the Foot and Ankle Ability Measure (FAAM) and the Activities of Daily Living Subscale (ADL). RESULTS: The prevalence of MMO in the operative treatment of OCLT was 15.9%. Most of the osteotomies were performed in OCL of the medial talar dome (76.8%) and in more serious lesions with an ICRS grade of III (29.1%) and IV (61.4%). More than half of the osteotomies (55.6%) were performed during revision surgery. A matched pair analysis of n = 44 patients who underwent AMIC® via arthrotomy and MMO vs. arthrotomy alone showed no significant differences in patient-reported outcome measures (PROMs, i.e. FAAM-ADL, and FAOS) at 6,12 and 24 months. CONCLUSIONS: MMO are mostly used in the treatment of severe (≥ ICRS grade 3) OCL of the medial talar dome and in revision surgery. Functional and patient-reported outcome measures are not significantly affected by MMO compared to arthrotomy alone. TRIAL REGISTRATION: The German Cartilage Register (KnorpelRegister DGOU) was initially registered at the German Clinical Trials Register ( https://www.drks.de , register number DRKS00005617, Date of registration 03.01.2014) and was later expanded by the ankle module.

The efficacy of autologous matrix-induced chondrogenesis (AMIC) for osteochondral lesions of the talus in the mid-long term: a systematic review and meta-analysis.

PURPOSE: The objective of this study was to provide a comprehensive review of the existing literature regarding the treatment of osteochondral lesions of the talus (OLT) using autologous matrix-induced chondrogenesis (AMIC), while also discussing the mid-long term functional outcomes, complications, and surgical failure rate. METHODS: We searched Embase, PubMed, and Web of Science for studies on OLT treated with AMIC with an average follow-up of at least 2 years. Publication information, patient data, functional scores, surgical failure rate, and complications were extracted. RESULTS: A total of 15 studies were screened and included, with 12 case series selected for meta-analysis and 3 non-randomized controlled studies chosen for descriptive analysis. The improvements in the Visual Analog Scale (VAS), the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot, and Tegner scores at the last follow-up were (SMD = - 2.825, 95% CI - 3.343 to - 2.306, P < 0.001), (SMD = 2.73, 95% CI 1.60 to 3.86, P < 0.001), (SMD = 0.85, 95% CI 0.5 to 1.2, P < 0.001) respectively compared to preoperative values. The surgery failure rate was 11% (95% CI 8-15%), with a total of 12 patients experiencing complications. CONCLUSION: The use of AMIC demonstrates a positive impact on pain management, functional improvement, and mobility enhancement in patients with OLT. It is worth noting that the choice of stent for AMIC, patient age, and OLT size can influence the ultimate clinical outcomes. This study provides evidences supporting the safety and efficacy of AMIC as a viable treatment option in real-world medical practice.

Comparable Clinical and Functional Outcomes Between Osteochondral Allograft Transplantation and Autologous Chondrocyte Implantation for Articular Cartilage Lesions in the Patellofemoral Joint at a Mean Follow-up of 5 Years.

PURPOSE: To assess clinical outcomes and return to sport (RTS) rates among patients that undergo osteochondral allograft (OCA) transplantation and autologous chondrocyte implantation (ACI) or matrix-induced autologous chondrocyte implantation (MACI), for patellofemoral articular cartilage defects. METHODS: A retrospective review of patients who underwent an OCA or ACI/MACI from 2010-2020 was conducted. Patient-reported outcomes (PROs) collected included: Visual Analog Scale for pain/satisfaction, Knee Injury and Osteoarthritis Outcome Score (KOOS), and RTS. The percentage of patients that met the Patient Acceptable Symptom State (PASS) for KOOS was recorded. Logistic regression was used to identify predictors of worse outcomes. RESULTS: A total of 95 patients were included (78% follow-up) with ACI or MACI performed in 55 cases (57.9%) and OCA in 40 (42.1%). A tibial tubercle osteotomy was the most common concomitant procedure for OCA (66%) and ACI/MACI (98%). Overall, KOOS pain was significantly poorer in OCA than ACI/MACI (74.7, 95% CI [68.1, 81.1] vs 83.6, 95% CI [81.3, 88.4], p= 0.012), while the remaining KOOS subscores were non-significantly different (all p>0.05). Overall, RTS rate was 54%, with no significant difference in return between OCA or ACI/MACI (52% vs 58%, p= 0.738). There were 26 (27%) reoperations and 5 (5%) graft failures in the entire group. Increasing age was associated with lower satisfaction in OCA and poorer outcomes in ACI/MACI, while larger lesion area was associated with lower satisfaction and poorer outcomes in ACI/MACI. CONCLUSION: Clinical and functional outcomes were similar in patients that underwent OCA or ACI/MACI for patellofemoral articular cartilage defects at a mean follow-up of 5 years. Patients who received OCA had a higher proportion of degenerative cartilage lesions and, among those with trochlear lesions, reported higher pain at final follow-up than their ACI/MACI counterparts. Overall, increasing age and a larger lesion size were associated with worse patient-reported outcomes.

Cytokine Receptor-like Factor 1 (CRLF1) and Its Role in Osteochondral Repair.

BACKGROUND: Since cytokine receptor-like factor 1 (CRLF1) has been implicated in tissue regeneration, we hypothesized that CRLF1 released by mesenchymal stem cells can promote the repair of osteochondral defects. METHODS: The degree of a femoral osteochondral defect repair in rabbits after intra-articular injections of bone marrow-derived mesenchymal stem cells (BMSCs) that were transduced with empty adeno-associated virus (AAV) or AAV containing CRLF1 was determined by morphological, histological, and micro computer tomography (CT) analyses. The effects of CRLF1 on chondrogenic differentiation of BMSCs or catabolic events of interleukin-1beta-treated chondrocyte cell line TC28a2 were determined by alcian blue staining, gene expression levels of cartilage and catabolic marker genes using real-time PCR analysis, and immunoblot analysis of Smad2/3 and STAT3 signaling. RESULTS: Intra-articular injections of BMSCs overexpressing CRLF1 markedly improved repair of a rabbit femoral osteochondral defect. Overexpression of CRLF1 in BMSCs resulted in the release of a homodimeric CRLF1 complex that stimulated chondrogenic differentiation of BMSCs via enhancing Smad2/3 signaling, whereas the suppression of CRLF1 expression inhibited chondrogenic differentiation. In addition, CRLF1 inhibited catabolic events in TC28a2 cells cultured in an inflammatory environment, while a heterodimeric complex of CRLF1 and cardiotrophin-like Cytokine (CLC) stimulated catabolic events via STAT3 activation. CONCLUSION: A homodimeric CRLF1 complex released by BMSCs enhanced the repair of osteochondral defects via the inhibition of catabolic events in chondrocytes and the stimulation of chondrogenic differentiation of precursor cells.

Osteochondral Injuries of the Talus.

Osteochondral lesions of the talus are a common sequelae of trauma and are often associated with ankle sprains and ankle fractures. Because the surface of the talus is composed primarily of hyaline cartilage, the regenerative capacity of these injuries is limited. Therefore, several open and arthroscopic techniques have been described to treat osteochondral injuries of the talus and underlying bone marrow lesions. Throughout this review, these treatment options are discussed along with their indications and currently reported outcomes. A commentary on the authors' preferences among these techniques is also provided.

A Biomimetic Osteochondral Scaffold Augmented With Filtered Bone Marrow Aspirate for the Treatment of Joint Surface Lesions in the Knee.

BACKGROUND: Multilayered osteochondral scaffolds are becoming increasingly utilized for the repair of knee joint surface lesions (KJSLs). However, the literature on predictive factors is rather limited. PURPOSE: To (1) evaluate the clinical outcomes and safety of a combined single-step approach using a biomimetic collagen-hydroxyapatite scaffold (CHAS) and filtered bone marrow aspirate (fBMA) for the treatment of KJSLs and (2) identify significant predictors of the treatment outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: All patients who underwent surgery because of a KJSL (size ≥1.5 cm2; International Cartilage Regeneration & Joint Preservation Society grades 3-4) using the combination above were selected from a hospital registry database (100 patients; minimum 2-year follow-up). Patient characteristics, medical history, knee joint and lesion status, intraoperative details, and cellular parameters of the injected fBMA were collected. The arthroscopic evaluation of chondral and meniscal tissue quality in all knee compartments was performed using the Chondropenia Severity Score. Treatment outcomes were determined clinically using patient-reported outcome measures (Knee Injury and Osteoarthritis Outcome Score, EuroQol-5 Dimensions-3 Levels, EuroQol-Visual Analog Scale, and Tegner Activity Scale) and by assessing the occurrence of serious adverse events and graft failure. Multivariable regression analysis was performed to identify significant predictors of the treatment outcomes. RESULTS: At a mean follow-up of 54.2 ± 19.4 months, 78 (87%) patients completed the questionnaires with significant improvements toward the baseline (P < .00625): KOOS Pain subscale from 62 ± 17 to 79 ± 18, KOOS Total score from 57 ± 16 to 70 ± 20, EuroQol-Visual Analog Scale from 61 ± 21 to 76 ± 16, EuroQol-5 Dimensions-3 Levels from 0.57 ± 0.20 to 0.80 ± 0.21, and Tegner Activity Scale from 2.8 ± 1.5 to 3.9 ± 1.9. The graft failure rate was 4%. A longer duration of preoperative symptoms, previous surgery, larger lesions, older age, and female sex were the main negative predictors for the treatment outcomes. The Chondropenia Severity Score and the number of fibroblast colony-forming units in fBMA positively influenced some of the clinical results and safety. CONCLUSION: A CHAS augmented with fBMA proved to be an adequate and safe approach for the treatment of KJSLs up to midterm follow-up. Based on the subanalysis of predictive factors, the surgical intervention should be performed in a timely and precise manner to prevent lesion enlargement, deterioration of the general knee cartilage status, and recurrent surgical procedures, especially in older and female patients. When a CHAS is used, the quantity of MSCs seems to play a role in augmentation. REGISTRATION: NCT06078072 (ClinicalTrials.gov identifier).

Effect of Cigarette Smoking on Postoperative Outcomes After Arthroscopic Bone Marrow Stimulation for Osteochondral Lesions of the Talus.

BACKGROUND: Bone marrow stimulation (BMS) is presently considered first-line surgical treatment for osteochondral lesions of the talus (OLTs); however, some patients still experience pain or dysfunction after surgery, and the reasons for success or failure remain somewhat unclear. This study aimed to investigate the effect of smoking on postoperative outcomes after arthroscopic BMS for OLTs. METHODS: Consecutive patients with OLTs who underwent BMS between January 2017 and January 2020 were included. Smokers were defined as patients who actively consumed cigarettes before surgery and postoperatively, whereas nonsmokers were patients who never smoked. Visual analog scale (VAS), American Orthopaedic Foot & Ankle Society ankle hindfoot score (AOFAS), Karlsson-Peterson, and Tegner scores were assessed preoperatively and at follow-up. Additionally, a general linear model (GLM) was performed, followed by the interaction analysis to explore the potential influence of smoking. RESULTS: The study enrolled 104 patients with a mean follow-up of 30.91 ± 7.03 months, including 28 smokers and 76 nonsmokers. There were no significant differences in patient age (35.2 ± 10.0 years vs 37.6 ± 9.7 years, P = .282) or OLT area (63.7 ± 38.7 mm2 vs 52.8 ± 37.0 mm2, P = .782). Both univariate analysis and GLM revealed that smoking was associated with worse postoperative pain levels, Karlsson-Peterson, and AOFAS scores (P < .05). The interaction analysis showed a significant interaction between smoking and OLT area for postoperative Karlsson-Peterson scores (general ankle function) (P = .031). Simple main effects analysis revealed that the negative effect of smoking on Tegner score significantly increased among patients >32 years old or with OLT area>50 mm2 (P < .05). CONCLUSION: Smoking was associated with worse clinical outcomes following BMS of OLTs. As the size of OLTs increased, the difference in general ankle function between smokers and nonsmokers also increased. Furthermore, smokers who were older than 32 years or had larger OLTs were less likely to resume participation in high-level activities.

Medial cystic osteochondral lesions of the talus exhibited lower sports levels, higher cyst-presence rate, and inferior radiological outcomes compared with lateral lesions following arthroscopic bone marrow stimulation.

PURPOSE: To compare the patient-reported outcomes and radiological outcomes of the patients with medial- and lateral-cystic osteochondral lesions of the talus (OLTs) following bone marrow stimulation (BMS). METHODS: Patients with cystic OLTs who underwent BMS between January 2016 and February 2021 were retrospectively analyzed, and the minimum follow-up time was more than 24 months. Patients were paired in a 1:1 ratio (medial-: lateral-cystic OLT; MC-OLT: LC-OLT) based on the OLT area within 30mm2, follow-up within 1 year, age within 5 years, and ligament surgery (Yes/No). The Visual analog scale, Foot and Ankle Ability Measure (FAAM)-Activities of Daily Life and Sports scores were assessed preoperatively and postoperatively. The magnetic resonance observation of cartilage repair tissue (MOCART) scores, and presence of cysts after BMS were also evaluated. Additionally, the receiver operating characteristic curve was performed. RESULTS: The matched patients were divided into the MC-OLT(n=31, 43.35±12.32 months) and LC-OLT groups (n=31, 43.32±14.88 months, P=.986). Thirty patients of each group achieved a power of 80% and an α = 0.05 in this study. The MC-OLT group showed significantly less improvement in FAAM-ADL and sports scores (P = .034, P <0.001, respectively), lower MOCART scores (80.80±11.91 vs. 86.00±8.50, P = .010), and higher presence-rate of cyst after BMS (45.16% vs. 16.12%, P = .013). Regarding FAAM sports scores, the LC-OLT group had significantly more patients exceeding the MCID (80.64% vs. 51.61%, P = .031). Furthermore, an OLT depth of 7.23mm (sensitivity: 78.6%; specificity: 70.6%) might serve as a cut-off value for predicting the presence of cysts in medial-cystic OLTs following BMS. CONCLUSION: Medial cystic OLTs exhibited markedly lower sports levels, higher cyst-presence rate, and inferior radiological outcomes following BMS than lateral counterparts. Additionally, an OLT depth of 7.23mm could be the cut-off value for predicting the presence of cysts regarding medial-cystic OLTs after BMS. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Long-Term Structural Changes in the Osteochondral Unit in Patients with Osteoarthritis Undergoing Corrective Osteotomy with Platelet-Rich Plasma or Stromal Vascular Fraction Post-Treatment.

This pilot study examined the long-term structural changes in the osteochondral unit of 20 patients with knee osteoarthritis (KOA) who underwent high tibial osteotomy (HTO) and received post-treatment with either platelet-rich plasma (PRP) or stromal vascular fraction (SVF). Ten patients were injected with autologous PRP (PRP subgroup), while another ten patients received autologous SVF (SVF subgroup) six weeks after surgery and were monitored for 18 months. Histological samples of bone and cartilage (2 mm in diameter and 2 cm long) were taken from tibial and femoral sites during surgery and 18-month post-HTO, and morphometric analyses were conducted using Mega-Morf12 software. Both post-treatment resulted in an increase in articular cartilage height at both sites (p < 0.001 in the tibia and femur), indicating positive outcomes. Significant improvements in subchondral and trabecular bone architecture were also observed, with SVF injection showing higher reparative capacity in terms of bone volume (p < 0.001 for the tibia and p = 0.004 for the femur), subchondral bone height (p < 0.001 for the tibia and p = 0.014 for the femur), trabecular bone volume (p < 0.001 for the femur), and intertrabecular space (p = 0.009 for the tibia and p = 0.007 for the femur). This pilot study, for the first time, demonstrates that HTO surgery combined with PRP and SVF post-treatments can lead to significant enhancements in knee articular cartilage and bone architecture in KOA patients, with SVF showing higher regenerative potential. These findings may contribute to improving treatment strategies for better clinical outcomes in HTO therapy for patients with KOA.

Functionally graded hydrogels with opposing biochemical cues for osteochondral tissue engineering.

Osteochondral tissue (OC) repair remains a significant challenge in the field of musculoskeletal tissue engineering. OC tissue displays a gradient structure characterized by variations in both cell types and extracellular matrix components, from cartilage to the subchondral bone. These functional gradients observed in the native tissue have been replicated to engineer OC tissuein vitro. While diverse fabrication methods have been employed to create these microenvironments, emulating the natural gradients and effective regeneration of the tissue continues to present a significant challenge. In this study, we present the design and development of CMC-silk interpenetrating (IPN) hydrogel with opposing dual biochemical gradients similar to native tissue with the aim to regenerate the complete OC unit. The gradients of biochemical cues were generated using an in-house-built extrusion system. Firstly, we fabricated a hydrogel that exhibits a smooth transition of sulfated carboxymethyl cellulose (sCMC) and TGF-ß1 (SCT gradient hydrogel) from the upper to the lower region of the IPN hydrogel to regenerate the cartilage layer. Secondly, a hydrogel with a hydroxyapatite (HAp) gradient (HAp gradient hydrogel) from the lower to the upper region was fabricated to facilitate the regeneration of the subchondral bone layer. Subsequently, we developed a dual biochemical gradient hydrogel with a smooth transition of sCMC + TGF-ß1 and HAp gradients in opposing directions, along with a blend of both biochemical cues in the middle. The results showed that the dual biochemical gradient hydrogels with biochemical cues corresponding to the three zones (i.e. cartilage, interface and bone) of the OC tissue led to differentiation of bone-marrow-derived mesenchymal stem cells to zone-specific lineages, thereby demonstrating their efficacy in directing the fate of progenitor cells. In summary, our study provided a simple and innovative method for incorporating gradients of biochemical cues into hydrogels. The gradients of biochemical cues spatially guided the differentiation of stem cells and facilitated tissue growth, which would eventually lead to the regeneration of the entire OC tissue with a smooth transition from cartilage (soft) to bone (hard) tissues. This promising approach is translatable and has the potential to generate numerous biochemical and biophysical gradients for regeneration of other interface tissues, such as tendon-to-muscle and ligament-to-bone.

The Comparison of the Results of Microfracture and Mosaicplasty in Talus Osteochondral Lesions.

PURPOSE:  This study aims to compare the mid-term functional outcomes of microfracture and mosaicplasty techniques in talus osteochondral lesions. MATERIALS AND METHODS: This study consists of 47 patients with talus osteochondral lesions who underwent arthroscopic surgery. These patients were divided into two groups: microfracture (28 patients) and mosaicplasty (19 patients). The American Orthopedic Foot and Ankle Society (AOFAS) scoring system was used to evaluate ankle function, and the Visual Analog Scale (VAS) score was used for pain assessment. RESULTS: The mean follow-up period was 26 months (range 10-36 months). It was determined that the mean preoperative AOFAS score of individuals in the mosaicplasty group was 38.84±2.83, and the postoperative AOFAS score was 78.79±3.91. A statistically significant difference was found between the two measurements of AOFAS scores (preoperative and postoperative) in the mosaicplasty group (*t=33.756; p<0.001). The effect size for this difference observed in the mosaicplasty group was determined to be r=0.992 (large). Similarly, a statistically significant difference was found between the two measurements of AOFAS scores (preoperative and postoperative) in the microfracture group (*t=28.152; p<0.001). The effect size for this difference observed in the microfracture group was determined to be r=0.983 (large). CONCLUSION: We believe that both treatment methods have similar positive effects on pain and ankle function. However, larger controlled studies with longer follow-up periods are needed to reach a definitive conclusion.

Autologous osteoperiosteal transplantation is effective in the treatment of single cystic osteochondral lesions of the talus and the prognostic impact of age should be emphasized.

PURPOSE: To investigate the clinical efficacy and prognostic factors associated with autologous osteoperiosteal transplantation for the treatment of single cystic osteochondral lesions of the talus (OLT). METHODS: The clinical data of patients with single cystic OLT undergoing autologous osteoperiosteal transplantation at the Department of Foot and Ankle Surgery of our hospital between 2018 and 2022, including complete follow-up, were retrospectively analyzed. Imaging data from each patient were imported into Mimics software to measure the surface area, volume and depth of the lesions. Then, the talus nine-compartment partitioning method was used to partition the injury site. Preoperative and final follow-up assessments were performed using the American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS) for pain and 36-item Short-Form Health Survey (SF-36) to evaluate treatment efficacy and analyze prognostic factors. RESULTS: Of the 31 patients with single cystic OLT with a complete set of follow-up data, there were 17 males and 14 females, with a mean age of 43.3 ± 13.6 years, a mean follow-up time of 30.1 ± 14.0 months and a mean illness duration of 30.4 ± 20.0 months. The postoperative final follow-up AOFAS score was 90.7 ± 5.5; this represented significant improvement when compared to the preoperative score of 57.0 ± 8.5 (P < 0.001). The final postoperative follow-up VAS score was 18.5 ± 8.3; this was significantly better than the preoperative score of 57.8 ± 8.7 (P < 0.001). The physical component summary (PCS) score and mental component summary (MCS) score on the SF-36 scale showed significant improvement at the final postoperative follow-up when compared to preoperative scores (p < 0.001). No other complications were observed during follow-up, such as wound infection or pain at the donor site. One of the patients showed less improvement, which may be related to premature weight-bearing or re-sprained ankle after surgery. There was no significant correlation between the duration of illness, gender and the location, depth, surface area and volume of the OLT and the postoperative scores. However, patient age showed a significant negative correlation with the postoperative SF-36 PCS and MCS scores. CONCLUSION: Autologous osteoperiosteal transplantation for single cystic OLT demonstrated good clinical efficacy with a low incidence of complications. Furthermore, age represents an important factor influencing prognosis. LEVEL OF EVIDENCE: Level II.

Ankle Instability: Facts and Myths to Protect Your Cartilage Repairing.

The majority of patients with an osteochondral lesion of the talus (OLT) report a history of trauma. Therefore, it is important to assess for concomitant ankle instability when dealing with patients with a symptomatic OLT. The History; Alignment; Ligaments; Others "(HALO)" approach can be a helpful tool in the evaluation of patients with an OLT. If conservative treatment fails, surgery may be indicated. Although there is a lack of comparative studies investigating the effect of stabilization procedures on cartilage repair, we believe that addressing instability is a key factor in improving patient outcome.

Regeneration: AT-AMIC Technique: Limits and Indication.

Osteochondral lesion of the talus (OLT) is a commune cause of chronic ankle pain. Symptomatic lesions require surgical treatment. Currently, lesions with diameter less than 107.4 mm2 are treated with bone marrow stimulating technique with notable success rate. However, more extensive lesions show less predictable surgical results. Autologous matrix-induced chondrogenesis has proven to provide satisfactory medium and long-term results on OLTs. In the current review, we describe an all-arthroscopic technique and the Milan-Tel Aviv lesion assessment protocol.

Evaluation of the efficacy of autogenous tibial periosteal bone grafting in the treatment of osteochondral lesions of the talus and analysis of three-dimensional factors in the necrotic zone.

PURPOSE: This study aims to explore the clinical value of autogenous tibial periosteal bone grafting in the treatment of osteochondral lesions of the talus (OLT) and analyze the three-dimensional factors in the necrotic zone of the talus. METHODS: A retrospective analysis was performed on 36 patients who underwent autogenous tibial periosteal bone grafting in the Foot and Ankle Surgery Department of our hospital between September 2018 and September 2022. The American Orthopaedic Foot and Ankle Society (AOFAS), Visual Analogue Scale (VAS), and Chinese Short-Form 36 Health Survey (SF-36) were used to evaluate treatment efficacy prior to surgery and at the last follow-up. Furthermore, Mimics 21.0 software was employed to measure the three-dimensional data of the necrotic area, including surface area, volume, and depth, in order to investigate their potential impact on patient prognosis. RESULTS: Among the 36 OLT patients who obtained complete follow-up, there were 22 males and 14 females. No complications such as surgical site infection, non-union of cartilage, post-traumatic arthritis, or donor site pain were observed. The AOFAS, VAS, and Chinese SF-36 scores of all patients at the last follow-up showed significant improvement compared to preoperative values. There was no significant correlation between the AOFAS, VAS, and Chinese SF-36 scores at the last follow-up and the depth, surface area, and volume of the necrotic zone. CONCLUSION: The use of autogenous tibial periosteal bone grafting can safely and effectively treat Hepple V OLT. Additionally, there is no significant correlation between the three-dimensional factors of the necrotic area and the prognosis of the patients.