The role of bone marrow edema on osteochondral lesions of the talus

The severity of preoperative bone marrow oedema negatively influences short-term clinical outcomes following arthroscopic bone marrow stimulation for osteochondral lesions of the talus

PURPOSE

The purpose of this study was to study the effects of the severity of preoperative bone marrow oedema (BME) on the postoperative short-term outcomes following bone marrow stimulation (BMS) for osteochondral lesions of the talus (OLTs) and to propose a new metric that combines volume and signal density to evaluate BME.

METHODS

Sixty-five patients with symptomatic OLTs (<100 mm2) and preoperative BME, who received BMS in our institution from April 2017 to July 2021 with follow-ups of 3, 6 and 12 months, were analysed retrospectively. The area, volume and signal value of the BME were collected on preoperative magnetic resonance imaging. The enroled patients were divided into two groups according to the BME index (BMEI), which was defined as the product of oedema relative signal intensity and the relation of oedema volume to total talar volume. Visual analogue scale, American Orthopedic Foot and Ankle Society (AOFAS), Tegner, Foot and Ankle Ability Measure (FAAM)-activities of daily living (ADL) and Sports scores were assessed before surgery and at each follow-up. The relationship between the scores and the volume, relative signal intensity and BMEI was explored.

RESULTS

Sixty-five patients with preoperative BME were divided into the mild (n = 33) and severe (n = 32) groups based on the BMEI. A significant difference was found for each score with the general linear model for repeated measures through all follow-up time points (p < 0.001). For the preoperative and 12-month postoperative changes of the enroled patients, 53 patients (81.5%) exceeded the minimal clinically important difference of AOFAS and 26 (40.0%) exceeded that of FAAM-sports in this study. The mild group showed significantly more improvement in AOFAS scores at 12 months (89.6 ± 7.0 vs. 86.2 ± 6.2) and FAAM-ADL scores at 6 months (83.6 ± 7.6 vs. 79.7 ± 7.7) and 12 months (88.5 ± 8.5 vs. 84.4 ± 7.7) than the severe group (p < 0.05). No significant difference of all the scores between the groups was found at 3 months. No significant correlation was found in each group between BMEI and clinical outcomes.

CONCLUSION

The severity of the preoperative BME negatively affected short-term clinical outcomes following arthroscopic BMS for OLTs. Worse clinical outcomes were shown at postoperative 6 and 12 months in patients with a high preoperative BMEI, which could be a favourable parameter for assessing the severity of BME and assist in developing personalised rehabilitation plans and determining the approach and timing of surgery.

LEVEL OF EVIDENCE

Level III.

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.

Osteochondral Lesions of the Talus: Etiology, Clinical Presentation, Treatment Options, and Outcomes

This article reviews the etiology, clinical presentation, classification schemes, and treatment options for osteochondral lesions of the talus. These lesions typically occur after a traumatic injury and are best diagnosed on MRI. Asymptomatic lesions and incidentally found lesions are best treated conservatively; however, acute displaced osteochondral fragments may require surgical treatment. Lesion characteristics may dictate surgical technique. Outcomes following surgical treatment may be impacted by patient age, BMI, and lesion characteristics.

Comparison of Arthroscopic Microfracture for Osteochondral Lesions of the Talus With and Without Small and Shallow Subchondral Cysts

BACKGROUND

Whether arthroscopic microfracture is effective in treating cystic osteochondral lesions of the talus (OLTs) remains controversial. In this study, outcome parameters in patients with small and shallow subchondral cysts are compared to patients without cysts with the hypothesis that equivalent outcomes may be found after primary microfracture treatment.

METHODS

From 2018 to 2021, all 50 OLTs treated with arthroscopic microfracture in the authors' hospital were retrospectively reviewed for eligibility. Single unilateral symptomatic lesions were included and divided into the cyst and noncyst groups, whereas kissing lesions and arthritic lesions were excluded. Numeric rating scale (NRS) scores, American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores, Tegner activity level scores, Foot and Ankle Ability Measure (FAAM) scores, and magnetic resonance (MR) imaging results were used to describe outcomes.

RESULTS

A total of 35 patients were included, 16 in the cyst group and 19 in the noncyst group. The patient characteristics were similar between the 2 groups (P > .05). In the cyst group the average cysts depth was 5.0 ± 1.3 mm. After a mean follow-up duration of 36.2 ± 10.2 months, no significant differences were found between the 2 groups in NRS, AOFAS, FAAM, or Tegner score improvement (P > .05). Three patients (19%) in the cyst group had no NRS score improvement.

CONCLUSION

OLTs with small and shallow subchondral cysts can be treated with arthroscopic microfracture and achieve similar outcomes as noncystic lesions. A few cystic lesions may not respond to microfracture treatment.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

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.

Clinical Outcomes of Osteochondral Fragment Fixation Versus Microfracture Even for Small Osteochondral Lesions of the Talus

BACKGROUND

The bone marrow stimulation (BMS) technique is performed for osteochondral lesions of the talus (OLTs) with a lesion size of <100 mm². The lesion defect is covered with fibrocartilage, and the clinical outcomes deteriorate over time. In contrast, the osteochondral fragment fixation can restore the native articular surface. The difference in clinical outcomes between these procedures is unclear.

PURPOSE

To compare the clinical outcomes of BMS and osteochondral fragment fixation for OLTs and examine the characteristics of patients with poor clinical outcomes of BMS.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

In total, 62 ankles in 59 patients with OLTs were included. BMS was performed for 26 ankles, and fixation was performed for 36 ankles. Clinical outcomes, including the American Orthopaedic Foot & Ankle Society (AOFAS) Ankle Hindfoot Scale and bone marrow edema (BME) as identified on magnetic resonance imaging, were compared between the 2 groups. On computed tomography scans, the lesion location was compared with or without BME in each group.

RESULTS

The AOFAS scores in the fixation group (97.3 ± 4.3 points) were significantly higher than those in the BMS group (91.3 ± 7.7 points), even when the lesion size was <100 mm² (P < .05). When comparing the ankles with or without BME in each group, the AOFAS scores at the final follow-up were significantly lower for the ankles with BME (88.6 ± 7.8 points) than for those without BME (95.0 ± 6.1 points) in the BMS group (P < .05). Lesions with BME in the sagittal plane were located more centrally than those without BME in the BMS group. In the fixation group, there were no significant differences in AOFAS scores and location of the lesion in ankles with or without BME.

CONCLUSION

The clinical outcomes of osteochondral fragment fixation are superior to those of BMS in OLTs, even for lesions sized <100 mm². Fixation is recommended even for small lesions, especially for more centralized lesions in the medial and lateral sides of the talus.

AMIC Procedure for Treatment of Osteochondral Lesions of Talus-A Systematic Review of the Current Literature

Osteochondral lesions of talus are a common injury where surgery is indicated in case of failed non-operative treatment or displaced lesions. Many studies have been conducted on the effectiveness of the AMIC procedure. The goal of our study is to create an overview of the current literature. A systematic search adhering to the PRISMA guidelines was conducted in PubMed (MEDLINE) and EMBASE on May 27, 2020. All included studies were evaluated according to the modified Coleman Methodology Score and information on study type, patient numbers, age, follow-up period, grade, location and size of the lesion, study in- and exclusion criteria, associated surgery, surgical technique, scaffold- and fixation technique, postoperative restrictions, reoperation rates, study outcome score, rehabilitation program, and surgical complications was extracted. Ninety-six studies were identified with 18 studies being included in our analysis. The overall quality of the literature was fair with no studies being graded as excellent. Data on preoperative evaluation and surgical technique, complication and reoperation rates, postoperative management and study outcome was extracted in order to create an overview of the current literature. The literature supports the use of the AMIC procedure as an effective treatment for osteochondral lesions of talus. Great heterogeneity exists and comparative studies are missing. While the number of studies on the topic is increasing further are needed and especially with optimized design.

Simultaneous Treatment of Osteochondral Lesion Does Not Affect the Mid- to Long-Term Outcomes of Ligament Repair for Acute Ankle Sprain: A Retrospective Comparative Study with a 3–11-Year Follow-up

Purpose

This study aims to evaluate the mid- to long-term outcome of concurrent arthroscopic treatment of osteochondral lesion (OCL) and open anatomical repair of lateral ankle ligaments for severe acute ankle sprain patients and compare them to the outcome of those without OCL.

Methods

A total of 166 patients with grade III acute lateral ankle ligament injuries underwent concurrent ankle arthroscopy and open anatomic ligament repair. Forty-three patients (group A) with OCL underwent arthroscopic treatment followed by open ligament repair. A total of 105 patients (group B) without OCL were followed up as the control. The evaluation parameters included sports recovery, postoperative visual analog scale (VAS) pain score, American Orthopaedic Foot and Ankle Society (AOFAS) score, Tegner score, sprain recurrence, satisfaction, and range of motion. Patients in group A were then subgroup-analyzed according to age, sex, body mass index, injury side, OCL location, and stage (Ferkel and Cheng’s staging system).

Results

The postoperative exercise level of the two groups recovered to more than 90% of the normal level (91.2% ± 11.2% in group A and 90.9% ± 13.3% in group B, n.s.). The average time of group A and group B to return to preinjury sports activity was respectively 4.4 ± 1.0 months and 4.4 ± 1.2 months with no significant difference (p = 0.716). No significant differences were found in the preoperation VAS pain score, AOFAS score, and Tegner score between the two groups. The postoperative VAS pain score in group A was significantly higher than that in group B (0.8 ± 1.7 vs. 0.3 ± 0.8, p = 0.027), but the difference was not clinically important. The postoperative VAS pain score of patients with stage D–F lesions was significantly higher than that of patients with stage B–C lesions (1.3 ± 2.1 vs. 0.3 ± 0.9, p = 0.038).

Conclusions

For the severe acute ankle sprain combined with OCL, the simultaneous arthroscopic treatment and open lateral ankle ligament repair achieved good mid- to long-term outcomes. Except that the pain was more pronounced than in the control group, there were no differences in other outcomes. Postoperative pain was positively correlated with the grade of OCL.

Correlation of Postoperative Imaging With MRI and Clinical Outcome After Cartilage Repair of the Ankle: A Systematic Review and Meta-analysis

Background:

Magnetic resonance imaging (MRI) is commonly used for evaluation of ankle cartilage repair, yet its association with clinical outcome is controversial. This study analyzes the correlation between MRI and clinical outcome after cartilage repair of the talus including bone marrow stimulation, cell-based techniques, as well as restoration with allo- or autografting.

Methods:

A systematic search was performed in MEDLINE, Embase, and Cochrane Collaboration. Articles were screened for correlation of MRI and clinical outcome. Guidelines of Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) were used. Chi-square test and regression analysis were performed to identify variables that determine correlation between clinical and radiologic outcome.

Results:

Of 2687 articles, a total of 43 studies (total 1212 cases) were included with a mean Coleman score of 57 (range, 33-70). Overall, 93% were case series, and 5% were retrospective and 2% prospective cohort studies. Associations between clinical outcome and ≥1 imaging variable were found in 21 studies (49%). Of 24 studies (56%) using the composite magnetic resonance observation of cartilage repair tissue (MOCART) score, 7 (29%) reported a correlation of the composite score with clinical outcome. Defect fill was associated with clinical outcome in 5 studies (12%), and 5 studies (50%) reported a correlation of T2 mapping and clinical outcome. Advanced age, shorter follow-up, and larger study size were associated with established correlation between clinical and radiographic outcome (P = .021, P = .028, and P = .033).

Conclusion:

Interpreting MRI in prediction of clinical outcome in ankle cartilage repair remains challenging; however, it seems to hold some value in reflecting clinical outcome in patients with advanced age and/or at a shorter follow-up. Yet, further research is warranted to optimize postoperative MRI protocols and assessments allowing for a more comprehensive repair tissue evaluation, which eventually reflect clinical outcome in patients after cartilage repair of the ankle.

Level of Evidence: Level III, systematic review and meta-analysis.

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.

Arthroscopic debridement of osteochondral lesions of the talus: A systematic review

BACKGROUND

Arthroscopic debridement (AD) for the osteochondral lesions of the talar dome (OLT) was widely documented in the nineties with satisfactory results. However, in modern treatment algorithms, its role is not described. The present systematic review aims to evaluate the current evidence on the clinical outcomes of AD in the management of OLT.

METHODS

Two independent reviewers searched PubMed, EMBASE, Scopus, and Virtual Health Library databases evaluating the clinical outcomes of AD of OLT with a minimum 6-month follow-up. The following terms "talus", "chondral", "cartilage", "injury", "lesion", "delamination", "damage", "excision", "curettage", "debridement", "chondrectomy", "chondroplasty", were used alone and in combination with Boolean operators AND and OR. Studies in which surgical technique was not described, an additional procedure was performed after debridement, and/or outcomes were not reported separately when more than one technique was implemented were excluded. The modified Coleman methodology score (mCMS) was used to evaluate the methodological quality of the included studies. A narrative analysis was conducted. Publication bias was assessed using the ROBIS tool.

RESULTS

AD showed satisfactory short and medium-term outcomes for the primary treatment of OLT irrespectively of size and depth. However, the heterogeneity of the included studies and the level of available evidence hinders its recommendation.

CONCLUSIONS

There is a paucity of evidence evaluating AD alone for OLT treatment in the last two decades. Bone-marrow stimulation techniques remain the first-line surgical strategy for OLT treatment without proven superiority. Adopting AD for OLT treatment instead of MF could represent a paradigm breakthrough in clinical practice given its many potential advantages while preserving the subchondral plate.

Is there clinical evidence to support autologous matrix-induced chondrogenesis (AMIC) for chondral defects in the talus? A systematic review and meta-analysis

BACKGROUND

The aim of this study is to systematically review the literature on clinical outcomes of patients who have undergone autologous matrix-induced chondrogenesis (AMIC) for treatment of osteochondral lesions of the talus (OCL) and compare the studies' outcomes.

METHODS

Pubmed and Embase were searched in January 2020 for articles concerning OCL surgery. Studies were included if they had a minimum 1-year follow-up and the primary measures were functional outcomes. The meta-analysis compared the Visual Analogic Score (VAS), the American Orthopedic Foot and Ankle Score (AOFAS), and the Foot Function Index (FFI) between baseline and follow-up of 1-2years, and 3-5years. A random effects model was used to evaluate outcome changes.

RESULTS

The search returned 15 studies, with a total of 492 patients. The VAS improved 4.45 and 4.6 points from baseline to the 1-2year and 3-5yearfollow-up, respectively (p<0.001). AOFAS improved 31.59 and 32.47 points from baseline to the 1-2year and 3-5yearfollow-up, respectively (p<0.001). The FFI showed a significant improvement of 30.93 points from baseline to year 3-5 (p<0.001). A total of 6 patients with revision surgeries have been reported within the follow up period. It was not possible to correlate clinical features like lesion size, surgical approach, and bone marrow stimulation technique to the reported outcome.

CONCLUSION

Surgical treatment of OCL via the AMIC procedure provided significant improvement in the functional outcome and pain scores when compared to the pre-operative values. Improvements were observed up to 5years post-operatively.

Autologous matrix-induced chondrogenesis for the treatment of osteochondral lesions of the talus: A systematic review

This study was performed to determine whether Autologous Matrix-Induced Chondrogenesis (AMIC) is an effective and safe treatment option for patients with symptomatic Osteochondral defects of the Talus (OCTs) and to identify factors that influence the clinical outcome. A systematic review of the literature was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Three reviewers independently conducted the literature search using the MEDLINE/PubMed database and the Cochrane Database of Systematic Reviews. The databases were queried using the terms "autologous" AND "matrix" AND "induced" AND "chondrogenesis." Thirteen studies were eligible for review. All studies that compared the preoperative and postoperative mean values of different clinical/functional scores showed significant clinical improvement. The final postoperative mean Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score ranged from 50.9 to 74.5. The included studies indicated that age and body mass index may have a detrimental impact on the postoperative outcome. A higher re-intervention rate is expected with the open technique, mainly because of hardware removal after malleolar osteotomy. This data analysis demonstrated that both arthroscopic and open AMIC procedures are effective and safe for the treatment of OCTs. Level IV, systematic review of therapeutic studies.

Subchondroplasty of the Ankle and Hindfoot for Treatment of Osteochondral Lesions and Stress Fractures: Initial Imaging Experience

Objective:To describe the imaging findings of patients treated with subchondroplasty (SCP) of the ankle and hindfoot. Materials and Methods: Eighteen patients (10 men, 8 women; age mean 43.1 years [range 20.1-67.7 years]) underwent ankle and hindfoot SCP at a single center over a 14-month period. Imaging data were reviewed retrospectively by 2 radiologists by consensus interpretation, including preoperative radiography (18), computed tomography (CT) (11), and magnetic resonance imaging (MRI) (13) and postoperative radiography (10), CT (4), and MRI (6). Follow-up imaging was acquired 1 month to 1.6 years following SCP. Results: Indications for SCP included symptomatic bone marrow lesions (BMLs) secondary to an osteochondral lesion (OCL) (16/18) or stress fracture (2/18). While focal radiodensity related to the SCP procedure was retrospectively identifiable on postoperative radiography in all except 1 case (10/11), postprocedural findings were not described by the interpreting radiologist in 6/11 cases. On CT, the average injected synthetic calcium phosphate (CaP) volume was 1.15 cm³ (SD = 0.33 cm³); mean CT attenuation of the injectate was 1220 HU (range 1058-1465 HU). In all patients who had pre- and postoperative MRI (5/18), BML size decreased on follow-up MRI. Extra-osseous extrusion of CaP was not seen on postoperative radiography, CT, or MRI. Conclusion: Physicians should be aware of the expanding preoperative indications and postoperative imaging findings of SCP, which is being performed with increasing frequency in the ankle and hindfoot.Levels of Evidence: Diagnostic, Level III: Retrospective cohort study.

Retrograde Drilling for Osteochondral Lesion of the Talus in Juvenile Patients

Background:

Retrograde drilling (RD) is generally used for treating osteochondral lesion of the talus (OLT) with a stable osteochondral fragment and nearly normal articular cartilage surface. Previous studies that included participants of various ages have reported good clinical results. This study aimed to clarify the clinical outcomes of RD for OLT in juvenile patients whose bone-forming ability and physical activity might affect the healing process.

Methods:

This retrospective study included 8 juvenile patients who underwent RD for OLT (5 boys and 3 girls, mean age 14.9 years, mean follow-up 2 years, 7 medial and 1 central lesion). American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score and ankle activity score were evaluated, and arthroscopic findings were graded according to the International Cartilage Research Society (ICRS) classification system. The condition of the underlying bone was assessed on preoperative computed tomographic images. The stability, incorporation, and subsidence of the osteochondral fragment, articular surface congruity, and the area of the bone marrow lesion (BML) were evaluated using magnetic resonance imaging (MRI).

Results:

AOFAS ankle-hindfoot score and ankle activity score significantly improved postoperatively. Arthroscopically, the lesions were classified as ICRS grade 0 or 1. Bone sclerosis or multiple small cysts of the underlying bone were observed in all patients. MRI demonstrated no signs of osteochondral fragment instability or subsidence, good or fair fragment incorporation, good articular surface congruity, or slight irregularity. The postoperative BML was reduced; however, these BMLs were still detectable at 1 year after surgery.

Conclusion:

Our data suggested that RD is an option for treating juvenile patients with OLT refractory to nonoperative treatment at short-term follow-up. Although bone sclerosis or multiple small cysts were identified in the underlying bone preoperatively and the BML under the osteochondral fragment remained postoperatively, clinical status such as pain and physical activity level were improved by RD.

Level of Evidence:

Level IV, retrospective case series.

How We Manage Bone Marrow Edema-An Interdisciplinary Approach

Bone marrow edema (BME) is a descriptive term for a common finding in magnetic resonance imaging (MRI). Although pain is the major symptom, BME differs in terms of its causal mechanisms, underlying disease, as well as treatment and prognosis. This complexity together with the lack of evidence-based guidelines, frequently makes the identification of underlying conditions and its management a major challenge. Unnecessary multiple consultations and delays in diagnosis as well as therapy indicate a need for interdisciplinary clinical recommendations. Therefore, an interdisciplinary task force was set up within our large osteology center consisting of specialists from internal medicine, endocrinology/diabetology, hematology/oncology, orthopedics, pediatrics, physical medicine, radiology, rheumatology, and trauma surgery to develop a consenus paper. After review of literature, review of practical experiences (expert opinion), and determination of consensus findings, an overview and an algorithm were developed with concise summaries of relevant aspects of the respective underlying disease including diagnostic measures, clinical features, differential diagnosis and treatment of BME. Together, our single-center consensus review on the management of BME may help improve the quality of care for these patients.

Arthroscopic microfracture vs. arthroscopic autologous matrix-induced chondrogenesis for the treatment of articular cartilage defects of the talus

PURPOSE

Microfracture is an established method to treat osteochondral defects of the talus. The value of the addition of an acellular matrix is still under debate. This study compared the results of arthroscopic microfracture vs. arthroscopic autologous matrix-induced chondrogenesis using a collagen I/III matrix (AMIC) in the management of articular cartilage defects of the talus.

METHODS

Patients with a minimum follow-up of 5 years after arthroscopic management for an articular cartilage defect of the talus with either microfracture alone or an additional acellular matrix were matched according to age, sex and BMI. The Hannover Scoring System for the ankle (HSS) and a Visual analog scale (VAS) for pain, function and satisfaction were used to evaluate the clinical outcome. Postoperative MRI was used to assess cartilage repair tissue based on the degree of defect repair and filling of the defect, integration to border zone, surface of the repair tissue, structure of the repair tissue, and subchondral bone alterations.

RESULTS

Thirty-two patients (16 microfracture, 16 AMIC) were included. No significant between-group differences were observed in demographic data and preoperative score values. Both groups showed statistically significant improvement when comparing the pre- and postoperative score values. No statistically significant differences were identified between the median values of the groups with the HSS (microfracture: 82 (range 71-96) points; AMIC 88 (range 40-98) points). Accordingly, no significant differences were observed for the VAS pain (microfracture: 0.95 (range 0-3.8); AMIC: 1.0 (range 0-8.5)), VAS function (microfracture: 8.4 (range 3.5-10); AMIC: 9.0 (range 1.5-10)) and VAS satisfaction (microfracture: 8.9 (range 2.8-10); AMIC: 9.45 (range 1.5-10)). MRI showed regeneration of tissue in the treated area without differences between the two groups.

CONCLUSION

Good clinical results were observed for arthroscopic microfracture with or without an additional acellular collagen I/III matrix in the treatment for articular cartilage defects of the talus. It appears that for defects as treated in this study, it is not worthwhile adding the collagen I/III matrix to the microfractures.

LEVEL OF EVIDENCE

III.

Identification of bone marrow edema of the ankle: diagnostic accuracy of dual-energy CT in comparison with MRI

OBJECTIVE

To evaluate the diagnostic accuracy of dual-energy computed tomography (DECT) to identify bone marrow edema (BME) of the ankle.

METHODS

This prospective institutional review board approved study included 40 consecutive patients (29 males and 11 females; mean age of 32.3 years) studied with DECT (80 kV and tin filter 150 kV) and MRI within 10 days. DECT data were post-processed for generating non-calcium images of the ankle. Two radiologists evaluated the presence of BME on color-coded maps. Diagnostic accuracy values for diagnosing BME were calculated for DECT maps (qualitative assessment) and for CT numbers (quantitative assessment) by using receiver operator curves and area under the curve (AUC), using MRI as the gold standard. Interobserver and intraobserver agreements were calculated with k-statistics. A p < 0.05 was considered statistically significant.

RESULTS

DECT depicted BME in 23/25 patients (92.0%). The sensitivity, specificity, PPV and NPV, and accuracy achieved by evaluating the DECT images were 92.0, 86.6, 92.0, 84.6, and 90.0%, for reader 1 and 88.0, 86.6, 91.6, 78.6, and 87.5, for reader 2, respectively. The interobserver and intraobsever agreements were near perfect (k = 0.87 and k = 0.83, respectively). DECT numbers were significantly different between positive (mean - 12.6 ± 29.6 HU) and negative cases (mean - 64.2 ± 34.5 HU) with a p value < 0.001. By using - 20HU cutoff to identify BME (AUC of 0.896.), the sensitivity, specificity, PPV and NPV, and accuracy of the quantitative analysis were 88.0, 92.6, 95.7, 92.6, and 87.5%, respectively.

CONCLUSION

DECT represents an accurate imaging tool for demonstration of BME of the ankle when compared to MRI.