High-Density Autologous Chondrocyte Implantation as Treatment for Ankle Osteochondral Defects

Intermediate-Term Clinical Outcomes of High-Density Autologous Chondrocyte Implantation in Patients with Concomitant Anterior Cruciate Ligament Reconstruction and Focal Chondral Lesions

OBJECTIVE

To investigate intermediate-term clinical results in patients with concomitant anterior cruciate ligament (ACL) reconstruction and chondral defect treated with high-density autologous chondrocyte implantation (HD-ACI) compared to patients without ACL tear but with a chondral lesion and HD-ACI treatment.

DESIGN

Forty-eight patients with focal chondral lesions underwent HD-ACI (24 with ACL reconstruction after an ACL injury and 24 with an intact ACL). Follow-up assessments occurred at 6, 12, and 24 months. Patient-reported knee function and symptoms were assessed using the International Knee Documentation Committee (IKDC) questionnaire, pain was measured using the Visual Analog Scale (VAS), and adverse events were monitored. Physical activity was assessed using the Tegner Activity Level Scale, and cartilage healing was evaluated with the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score.

RESULTS

No significant adverse events occurred during follow-up. Both groups showed significant improvements at 2 years compared to baseline (VAS: 8.0 ± 1.3 to 1.4 ± 2.0 [normal ACL]; 7.4 ± 2.3 to 2.1 ± 2.3 [ACL reconstruction]; IKDC: 39.2 ± 10.6 to 76.1 ± 22.0 [intact ACL]; 35.6 ± 12.1 to 74.6 ± 20.9 [ACL reconstruction]). Patients in both groups exceeded the minimal clinically important difference (MCID) for IKDC scores. The Tegner Activity Level Scale decreased immediately after surgery and increased after 2 years, with 70.6% (normal ACL) and 89.5% (ACL reconstruction) returning to their preinjury activity levels. No significant differences in the MOCART score were observed between the groups.

CONCLUSIONS

ACL reconstruction does not appear to reduce the outcomes (at 2 years) of HD-ACI.

Pleiotrophin inhibited chondrogenic differentiation potential of dental pulp stem cells

OBJECTIVE

Studies have shown that the levels of pleiotrophin (PTN) are greatly elevated in the synovial fluid and cartilage in osteoarthritis. Therefore, the purpose of this study was to investigate the effect and mechanism of PTN on the chondrogenic differentiation of DPSCs in inflammatory and normal microenvironments.

MATERIALS AND METHODS

A lentiviral vector was used to deplete or overexpress PTN in DPSCs. The inflammatory microenvironment was simulated in vitro by the addition of IL-1β to the culture medium. The chondrogenic differentiation potential was assessed using Alcian Blue staining and the main chondrogenic markers. A dual-luciferase reporter assay was used to explore the relationship between miR-137 and PTN.

RESULTS

The results showed that 0.1 ng/mL IL-1β treatment during chondrogenic induction greatly impaired the chondrogenic differentiation of DPSCs. Supplementation with PTN and PTN overexpression inhibited chondrogenic differentiation of DPSCs, while PTN depletion promoted chondrogenic differentiation. MiR-137 negatively regulated the expression of PTN by binding to the 3'UTR of its mRNA. Moreover, miR-137 promoted chondrogenic differentiation of DPSCs in normal and inflammatory microenvironments.

CONCLUSION

Our results suggest that PTN may play an inhibitory role in the chondrogenic differentiation of DPSCs in normal and inflammatory microenvironments, which is regulated by miR-137.

[Progress in surgical treatment of osteochondral lesion of talus]

Objective

To provide a comprehensive overview of the surgical treatments of osteochondral lesion of talus (OLT) and offer valuable insights for clinical practice.

Methods

The advantages and limitations of surgical treatments for OLT were comprehensively summarized through an extensive review of domestic and abroad relevant literature in recent years.

Results

Currently, there exist numerous surgical treatments for the OLT, all of which can yield favorable outcomes. However, each method possesses its own set of merits and demerits. The short-term effectiveness of bone marrow stimulation in treating primary OLT with a diameter less than 15 mm is evident, but its long-term effectiveness diminishes over time. Autologous osteochondral transplantation (AOT) and osteochondral allograft transplantation (OAT) are suitable for OLT with large defects and subchondral bone cysts. However, incomplete anatomical matching between the donor and recipient bones may results in the formation of new subchondral bone cysts, while AOT also presents potential complications at the donor site. In contrast to AOT and OAT, particulated juvenile cartilage allograft transplantation obviates the need for additional osteotomy. Furthermore, juvenile cartilage exhibits enhanced potential in delivering active chondrocytes to the site of cartilage defect, surpassing that of adult cartilage in tissue repair efficacy. Cell transplantation has demonstrated satisfactory effectiveness; however, it is associated with challenges such as the requirement for secondary surgery and high costs. Autologous matrix-induced chondrogenesis technology has shown promising effectiveness in the treatment of primary and non-primary OLT and OLT with large defect and subchondral bone cysts. However, there is a scarcity of relevant studies, most of which exhibit low quality. Adjuvant therapy utilizing biological agents represents a novel approach to treating OLT; nevertheless, due to insufficient support from high-quality studies, it has not exhibited significant advantages over traditional treatment methods. Furthermore, its long-term effectiveness remain unclear.

Conclusion

The optimal choice of surgical treatment for OLT is contingent not only upon the characteristics such as nature, size, and shape but also takes into consideration factors like advancements in medical technology, patient acceptance, economic status, and other pertinent aspects to deliver personalized treatment.

Second-Look Arthroscopy Shows Inferior Cartilage after Bone Marrow Stimulation Compared with Other Operative Techniques for Osteochondral Lesions of the Talus: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare cartilage quality after different surgical interventions for osteochondral lesions of the talus (OLT), evaluated by second-look arthroscopy. Secondary aims were to report concomitant diagnoses, and to correlate cartilage quality with clinical and radiological outcomes. This review hypothesizes that the cartilage repair after bone marrow stimulation (BMS) is inferior to the other available treatment options.

METHODS

PROSPERO ID: CRD42022311489. Studies were retrieved through PubMed, EMBASE (Ovid), and Cochrane Library. Studies were included if they reported cartilage quality after second-look investigation after surgical treatment of OLT. The primary outcome measure was the cartilage quality success and failure rates (%) per surgical intervention group. Correlations between the cartilage quality and clinical or radiological outcomes were calculated.

RESULTS

Twenty-nine studies were included, comprising 586 ankles that had undergone second-look arthroscopy on average 16 months after initial surgery. The success rate for BMS was 57% (95% confidence interval [CI] = 48%-65%), for fixation (FIX) 86% (95% CI = 70%-94%), for osteo(chondral) transplantation (OCT) 91% (95% CI = 80%-96%), for cartilage implementation techniques (CITs) 80% (95% CI = 69%-88%), and for retrograde drilling 100% (95% CI = 66%-100%). The success rate of BMS was significantly lower than FIX, OCT, and CIT (P < 0.01). There were no significant differences between other treatment groups. A moderate positive significant correlation between the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score and the International Cartilage Repair Society score (ICRS) was found (ρ = 0.51, P < 0.001).

CONCLUSIONS

Successful restoration of cartilage quality was found in the majority of surgically treated OLTs. However, BMS yields inferior cartilage quality compared with FIX, OCT, and CIT. Study Design. Systematic review and meta-analysis. Level of evidence. Level IV, systematic review and meta-analysis.

Clinical Applicability of Autologous Chondrocyte Implantation for the Treatment of Osteochondral Defects: A Meta-analysis

PURPOSE

Osteoarthritis and other joint disorders are the leading cause of disability in the elderly and the treatment of joint lesions is challenging. Autologous chondrocyte implantation (ACI) has been reported with variable effects for the treatment of osteochondral and other joint lesions. In this study, we performed a meta-analysis of the recent literature to determine the clinical applicability of ACI for osteochondral defects.

METHODS

A meta-analysis was performed on the recent literature showing the effects of ACI on osteochondral defects. The PUBMED, ScienceDirect and Google Scholar databases were used to identify eligible studies from Jan 2010 to Sep 2022. Both fixed and random models of meta-analysis were applied with all reported scoring systems to quantify the effectiveness of ACI on osteochondral defects.

RESULTS

The pool data of 965 patients as a case series after ACI from a fixed model showed a significant improvement in the osteochondral defects (odds ratio = 8.75, 95%CI = 7.127 to 10.743, p = 0.000). These results were further verified by a random model of meta-analysis. The data also showed a substantial heterogeneity among the studies used in the meta-analysis (Q-value = 160.41, I-squared = 87.53, p = 0.000). Furthermore, this meta-analysis also compared different ACI procedures with different scoring systems but the overall outcome remains the same as ACI was found to be useful for the healing of the osteochondral defects.

CONCLUSION

This meta-analysis of 965 case series revealed that the ACI markedly improved the damage osteochondral defects scores but the optimal treatment is still controversial, therefore further studies are needed to validate these findings in a clinical setting.

Postoperative Management of Osteochondral Lesions of the Ankle: A Survey Among German-Speaking Foot and Ankle Surgeons

OBJECTIVE

To assess the current treatment of osteochondral lesions of the ankle (OCLA) by German-speaking foot and ankle surgeons, focusing on the management of postoperative care and rehabilitation.

DESIGN

A questionnaire was created by a panel of 4 experienced foot and ankle surgeons on behalf of the "Clinical Tissue Regeneration" (CTR) working group of the German Society of Orthopaedics and Trauma Surgery (DGOU), and distributed electronically to members of the CTR, participants of the German Cartilage Registry (Knorpelregister DGOU©), and members of 6 German-speaking orthopedics or sports medicine societies. Results were classified depending on the consensus within the answers (agreement ≥75% "strong tendency," 50%-74% "tendency," 25%-49% "weak tendency," <25% "no tendency").

RESULTS

A total of 60 participants returned the questionnaire. The main results are as follows: regarding the frequency of surgical procedures for OCLA, refixation of the fragment, retrograde drilling, and bone marrow stimulation with or without using a matrix were performed by at least 75% of the surgeons and was considered a strong tendency. There was a strong tendency to stabilize the ankle (76.7%) and perform corrective osteotomies (51.7%). In total, 75.5% and 75% of the surgeons performed bone marrow stimulation with and without using a matrix, respectively. Corrective osteotomy and ankle stabilization were performed in 64.5% and 65.2% cases, respectively. Most participants included published recommendations on postoperative rehabilitation and the return to sports activities in their postoperative management. The main surgical procedures were considered the most critical factor in influencing the postoperative management by 81% of the participants (strong tendency). Adjunct surgical procedures such as corrective osteotomy and stabilization of the ankle were considered important by 67.8% of the respondents (tendency).

CONCLUSIONS

The management of OCLA varies among German-speaking foot and ankle surgeons. Therefore, guidelines remain essential to standardize the management of OCLA, to achieve improved and stable results. This survey will assist clinicians and patients with rehabilitation to return to sports after treating the ankle's cartilage injury.

Cartilage Defect Treatment Using High-Density Autologous Chondrocyte Implantation (HD-ACI)

Hyaline cartilage's inability to self-repair can lead to osteoarthritis and joint replacement. Various treatments, including cell therapy, have been developed for cartilage damage. Autologous chondrocyte implantation (ACI) is considered the best option for focal chondral lesions. In this article, we aimed to create a narrative review that highlights the evolution and enhancement of our chondrocyte implantation technique: High-Density-ACI (HD-ACI) Membrane-assisted Autologous Chondrocyte Implantation (MACI) improved ACI using a collagen membrane as a carrier. However, low cell density in MACI resulted in softer regenerated tissue. HD-ACI was developed to improve MACI, implanting 5 million chondrocytes per cm2, providing higher cell density. In animal models, HD-ACI formed hyaline-like cartilage, while other treatments led to fibrocartilage. HD-ACI was further evaluated in patients with knee or ankle defects and expanded to treat hip lesions and bilateral defects. HD-ACI offers a potential solution for cartilage defects, improving outcomes in regenerative medicine and cell therapy. HD-ACI, with its higher cell density, shows promise for treating chondral defects and advancing cartilage repair in regenerative medicine and cell therapy.

The Frequency and Severity of Complications in Surgical Treatment of Osteochondral Lesions of the Talus: A Systematic Review and Meta-Analysis of 6,962 Lesions

OBJECTIVE

The primary aim was to determine and compare the complication rate of different surgical treatment options for osteochondral lesions of the talus (OLTs). The secondary aim was to analyze and compare the severity and types of complications.

DESIGN

A literature search was performed in MEDLINE (PubMed), EMBASE (Ovid), and the Cochrane Library. Methodological quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS). Primary outcome was the complication rate per surgical treatment option. Secondary outcomes included the severity (using the Modified Clavien-Dindo-Sink Complication Classification System for Orthopedic Surgery) and types of complications. The primary outcome, the severity, and the sub-analyses were analyzed using a random effects model. A moderator test for subgroup-analysis was used to determine differences. The types of complications were presented as rates.

RESULTS

In all, 178 articles from the literature search were included for analysis, comprising 6,962 OLTs with a pooled mean age of 35.5 years and follow-up of 46.3 months. Methodological quality was fair. The overall complication rate was 5% (4%-6%; treatment group effect, P = 0.0015). Analysis resulted in rates from 3% (2%-4%) for matrix-assisted bone marrow stimulation to 15% (5%-35%) for metal implants. Nerve injury was the most observed complication.

CONCLUSIONS

In 1 out of 20 patients treated surgically for an OLT, a complication occurs. Metal implants have a significantly higher complication rate compared with other treatment modalities. No life-threatening complications were reported.

Arthroscopic defect size measurement in osteochondral lesions of the talus underestimates the exact defect size and size measurement with arthro-MRI (MR-A) and high-resolution flat-panel CT-arthro imaging (FPCT-A)

PURPOSE

The size of osteochondral lesions of the talus (OLTs) is highly relevant for their treatment. In addition to intraoperative measurement of defect size, preoperative planning by means of magnetic resonance imaging (MRI) or computed tomography (CT) is crucial.

METHODS

Four defects of different sizes and depths were created on the talar joint surface in 14 cadaver feet. All defects were evaluated, both arthroscopically and via arthrotomy with a probe. Arthro-MRI (MR-A) and high-resolution flat-panel CT arthro scans (FPCT-A) were acquired. Length, width, and depth were measured for every defect and the defect volume was calculated. To determine the exact defect size, each talar defect was filled with plastic pellets to form a cast and the casts were scanned using FPCT to create a 3D multiplanar reconstruction data set. Finally, the surgically measured values were compared with the radiological values and the exact defect size.

RESULTS

Overall, the surgically measured values (both arthroscopic and open) underestimated the exact defect size (p < 0.05). Arthroscopically determined defect length and width showed the largest deviation (p < 0.05) and underestimated the size in comparison with MR-A and FPCT-A. The FPCT-A measurements demonstrated higher correlation with both the arthroscopic and open surgical measurements than did the MR-A measurements (p < 0.05).

CONCLUSION

The exact defect size is underestimated on intraoperative measurement, in both arthroscopic and open approaches. Arthroscopic defect size measurement underestimates defect size in comparison with MR-A and FPCT-A. FPCT-A was shown to be a reliable imaging technique that allows free image reconstruction in every plane and could be considered as the new reference standard for preoperative evaluation of defect size in OLT.

Efficacy and safety of autologous chondrocyte implantation for osteochondral defects of the talus: a systematic review and meta-analysis

INTRODUCTION

Studies have reported various effects of autologous chondrocyte implantation (ACI) on osteochondral defects of the talus. Therefore, to assess the effectiveness of ACI for osteochondral defects of the talus, we used the meta-analytic approach.

MATERIALS AND METHODS

Electronic databases PubMed, Embase, and the Cochrane Library were systematically searched to identify eligible studies from their inception until November 2020. The random-effects model was used to calculate the incidence of success rate and American Orthopaedic Foot and Ankle Society (AOFAS) score for patients after ACI treatment. Subgroup analyses were also conducted based on age, technique, indication, size, and follow-up duration.

RESULTS

For the final meta-analysis, we selected 23 case series studies with a total of 458 patients with osteochondral defects of the talus. Overall, after ACI for patients with osteochondral defects of the talus, we noted that the incidence of success rate was 89% (95% confidence interval (95% CI) 85%-92%; P < 0.001). Moreover, after ACI for patients with osteochondral defects of the talus, the AOFAS score was 86.33 (95% CI 83.33-89.33; P < 0.001). Subgroup analysis showed that the AOFAS score after ACI is significantly different when stratified by the mean age of the patients (P = 0.006).

CONCLUSIONS

This study revealed that the use of ACI could provide a relatively high success rate and improve the AOFAS score for patients with osteochondral defects of the talus, which should be recommended in clinical practice.

Prognostic factors for the management of chondral defects of the knee and ankle joint: a systematic review

Purpose

Different surgical techniques to manage cartilage defects are available, including microfracture (MFx), autologous chondrocyte implantation (ACI), osteoarticular auto- or allograft transplantation (OAT), autologous matrix-induced chondrogenesis (AMIC). This study investigated the patient-related prognostic factors on the clinical outcomes of surgically treated knee and ankle cartilage defects.

Methods

This study followed the PRISMA statement. In May 2022, the following databases were accessed: PubMed, Google Scholar, Embase, and Scopus. All the studies investigating the outcomes of surgical management for knee and/or talus chondral defects were accessed. Only studies performing mesenchymal stem cells transplantation, OAT, MFx, ACI, and AMIC were considered. A multiple linear model regression analysis through the Pearson Product–Moment Correlation Coefficient was used.

Results

Data from 184 articles (8905 procedures) were retrieved. Female sex showed a positive moderate association with visual analogue scale at last follow-up (P = 0.02). Patient age had a negative association with the American Orthopaedic Foot and Ankle Score (P = 0.04) and Lysholm Knee Scoring Scale (P = 0.03). BMI was strongly associated with graft hypertrophy (P = 0.01). Greater values of VAS at baseline negatively correlate with lower values of Tegner Activity Scale at last follow-up (P < 0.0001).

Conclusion

The clinical outcomes were mostly related to the patients’ performance status prior surgery. A greater BMI was associated with greater rate of hypertrophy. Female sex and older age evidenced fair influence, while symptom duration prior to the surgical intervention and cartilage defect size evidenced no association with the surgical outcome. Lesion size and symptom duration did not evidence any association with the surgical outcome.

Location Distribution of 2,087 Osteochondral Lesions of the Talus

OBJECTIVE

The primary aim of this study was to evaluate the exact location distribution in patients with osteochondral lesions of the talus (OLTs) using a 9-grid scheme. The secondary aim is to match lesion location to lesion size, arthroscopic or open operation, and trauma occurrence.

METHODS

A systematic review was performed in the databases PubMed, EMBASE, and Cochrane. Search terms consisted of "talus" and "osteochondral lesion." Two independent reviewers evaluated search results and conducted the quality assessment using the Methodological Index for Non-Randomized Studies (MINORS). Primary outcome measure was OLT location in the 9 zone-grid. Secondary outcome measures were OLT size in 9-zones, preoperative radiological modality use, demographic lesion size variables as well as open or arthroscopic treatment.

RESULTS

Fifty-one articles with 2,087 OLTs were included. Heterogeneity concerning methodological nature was observed and methodological quality was low. The posteromedial (28%) and centromedial (31%) zones combined as one location was the location with the highest incidence of OLTs with a rate of 59%. Individual OLT size was reported for only 153 lesions (7%). Preoperative combination of X-ray and magnetic resonance imaging (MRI), and/or computed tomography (CT) was reported in 20 studies (43%). Trauma was reported in 78% of patients. Furthermore, 67% was treated arthroscopically and 76% received primary OLT treatment.

CONCLUSION

The majority of OLTs are located in the posteromedial and centromedial zone, while the largest OLTs were reported in the centrocentral zone. Further research is required to identify the prognostic impact of location occurrence on the outcomes following OLT treatment.

Influence of the Medial Malleolus Osteotomy on the Clinical Outcome of M-BMS + I/III Collagen Scaffold in Medial Talar Osteochondral Lesion (German Cartilage Register/Knorpelregister DGOU)

OBJECTIVE

Osteochondral lesions of the talus are common injuries, with one of the leading treatment options being the M-BMS (matrix-augmented bone marrow stimulation) + I/III collagen scaffold. Osteotomy of the medial malleolus is not unusual but presents the risk of malunion or irritation by hardware. The aim of the study was to analyze data from the German Cartilage Society (Knorpelregister DGOU) to evaluate the influence of medial malleolar osteotomy on clinical results of M-BMS + I/III collagen scaffold.

DESIGN

The ankle module of the Cartilage Register includes a total of 718 patients, while 45 patients met the inclusion criteria. Patients were treated with an M-BMS + I/III collagen scaffold of the medial talus, 30 without and 15 with an osteotomy of the medial malleolus. The follow-up evaluations included FAAM (Foot and Ankle Ability Measure), FAOS (Foot and Ankle Outcome Score), and VAS (visual analogue scale).

RESULTS

Forty-five patients (22 male, 23 female) aged between 18 and 69 years (mean: 34 years) were included in this study. Between preoperative and 12 months postoperative, we noted a significant improvement in FAAM-ADL (Activity of Daily Living) (P = 0.004) as well as FAOS-Pain (P = 0.001), FAOS-Stiffness (P = 0.047), FAOS-ADL (P = 0.002), FAOS-Sport (P = 0.001), and FAOS Quality of Life (P = 0.009). There was no significant difference between patients who underwent an osteotomy or not.

CONCLUSION

The results show a significant improvement in patients' outcome scores following a M-BMS + I/III collagen scaffold. No statistical difference was noted among those undergoing medial malleolar osteotomy.

The management of talar osteochondral lesions - Current concepts

Osteochondral lesions of the talus (OLTs) are a common complication following trauma, involving both the articular cartilage and the underlying subchondral bone, with variable aetiologies and often presenting with non-specific symptoms. Diagnosis of OLTs requires a combination of clinical assessment and imaging and despite many different treatment options, there is no generalised consensus regarding which option is the most effective. Left untreated, OLTs risk progressing to osteoarthritis. Acute non-displaced OLTs can be treated non-operatively. However, OLTs refractory to non-surgical care for three to six months may be suitable for surgical care. In these cases, conservative treatments are often unsuccessful, particularly for larger and more severe defects and so the majority require surgical intervention. Although bone marrow stimulation techniques remain the "gold standard" for lesions <150 mm2, there still requires a need for better long term clinical data and cost-benefit analyses compared with other treatment options. Biological attempts at either regenerating or replacing the articular cartilage are however demonstrating some promising results, but each with their own advantages and disadvantages. In this review, we summarise the clinical management of OLTs and present the current concepts of different treatment regimes.

Endogenous Repair and Regeneration of Injured Articular Cartilage: A Challenging but Promising Therapeutic Strategy

Articular cartilage (AC) has a very limited intrinsic repair capacity after injury or disease. Although exogenous cell-based regenerative approaches have obtained acceptable outcomes, they are usually associated with complicated procedures, donor-site morbidities and cell differentiation during ex vivo expansion. In recent years, endogenous regenerative strategy by recruiting resident mesenchymal stem/progenitor cells (MSPCs) into the injured sites, as a promising alternative, has gained considerable attention. It takes full advantage of body's own regenerative potential to repair and regenerate injured tissue while avoiding exogenous regenerative approach-associated limitations. Like most tissues, there are also multiple stem-cell niches in AC and its surrounding tissues. These MSPCs have the potential to migrate into injured sites to produce replacement cells under appropriate stimuli. Traditional microfracture procedure employs the concept of MSPCs recruitment usually fails to regenerate normal hyaline cartilage. The reasons for this failure might be attributed to an inadequate number of recruiting cells and adverse local tissue microenvironment after cartilage injury. A strategy that effectively improves local matrix microenvironment and recruits resident MSPCs may enhance the success of endogenous AC regeneration (EACR). In this review, we focused on the reasons why AC cannot regenerate itself in spite of potential self-repair capacity and summarized the latest developments of the three key components in the field of EACR. In addition, we discussed the challenges facing in the present EACR strategy. This review will provide an increasing understanding of EACR and attract more researchers to participate in this promising research arena.

Outcomes from Osteochondral Autograft Transplant or Mosaicplasty in 26 Patients with Type V Osteochondral Lesions of the Talus

Background

Mosaicplasty osteochondral transplantation (MOT) has been proved a feasible choice for the treatment of talus osteochondral injury. It can reduce ankle pain and allow performance of daily living activities and elementary sports. However, there are very little data on the restoration of normal life with large lesions. Our investigation focused on assessing outcomes in patients with large lesions.

Material/Methods

The MOT operation was used, and the donor site was located at the lateral condyle of the femur. Clinical evaluation included the Berndt and Harty outcome question, Visual Analog Scale (VAS) pain score (during rest, walking and running), American Orthopedic Foot and ankle Association (AOFAS) score, International Knee Documentation Committee (IKDC) subjective knee evaluation form, and the Short Form 36 (SF-36). Twenty-four months after surgery, the graft binding was assessed by MRI using the magnetic resonance observation of cartilage repair tissue (MOCART) score.

Results

We assessed 26 patients, including 14 males and 12 females. The average follow-up time was 33.9±5.2 months. The average lesion size was 173.1±23.5 mm². The average VAS score during rest improved from 4.62±0.85 preoperatively to 1.08±0.27 postoperatively (P<0.05), the score during walking improved from 5.19±0.63 preoperatively to 1.15±0.37 postoperatively (P<0.05), and the score during running improved from 6.08±0.74 preoperatively to 1.39±0.57 postoperatively (P<0.05). The average postoperative AOFAS ankle score improved to 91.5±2.6 (range, 88 to 96), compared with preoperative 75.0±2.8 (range, 70 to 79) (P<0.05). Two patients developed pain in the donor site of the knee joint, and both of them had 2 or more osteochondral plugs harvested. The postoperative SF-36 score increased to 92.2±2.4 (P<0.05). In the last follow-up, 18 patients answered the Berndt and Harty outcome question, all with “good” as the result.

Conclusions

MOT is a feasible choice for patients with larger lesions. It can improve the VAS/AOFAS/IKDC/SF-36 scores, and has high patient satisfaction. Graft incorporation helps improve patient quality of life. Our results indicate that a larger osteochondral plug area increases the risk of developing knee donor site pain.