Management of Osteochondral Lesions of the Talar Dome

Comparison of the medial midline and the anterolateral portal in ankle arthroscopy for the treatment of osteochondral lesions of the medial talus

PURPOSE

To compare the clinical efficacy and complication rates between the medial midline and anterolateral portals in ankle arthroscopy for treating medial osteochondral lesions of the talus (OLTs).

METHODS

We retrospectively analyzed patients with medial OLTs who underwent either a dual medial approach (via the medial midline and anteromedial portal) or a traditional approach (via the anterolateral and anteromedial portal) between June 2017 and January 2023. The degree of injury was evaluated by radiographs, computed tomography, and magnetic resonance imaging. Clinical outcomes were assessed using the visual analog scale (VAS), the American Orthopaedic Foot and Ankle Society (AOFAS) score, and the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scoring system. The incidence of postoperative complications, including superficial peroneal nerve (SPN) injury, was evaluated in all patients.

RESULTS

There were 39 patients in total; 16 patients underwent the dual medial approach, and 23 patients underwent the traditional approach. The mean age was 39.4 ± 9.0 years, and the mean follow-up duration was 18.7 ± 6.4 months. The clinical outcomes improved significantly in both groups (*P < 0.05), but there was no significant difference between the two groups (P > 0.05). Postoperative complications were mainly SPN injury. The incidence of SPN injury was 13.0% in the traditional approach group and 0% in the dual medial approach group, with no significant difference between the two groups (P > 0.05), but a trend of reduction in SPN injury was observed in the dual medial approach group.

CONCLUSION

The dual medial approach can also treat medial OLTs well, providing clear visualization and more convenient operation and reducing the possibility of injury to the SPN compared with the traditional approach. Therefore, we consider that the MM portal would be a good alternative to the anterolateral portal in treating medial OLTs.

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.

Reporting of Morphology, Location, and Size in the Treatment of Osteochondral Lesions of the Talus in 11,785 Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

Uniformity of reporting is a requisite to be able to compare results of clinical studies on the treatment of osteochondral lesions of the talus (OLT). The primary aim of this study was to evaluate the frequency and quality of reporting of size, morphology, and location of OLTs.

DESIGN

A literature search was performed from 1996 to 2023 to identify clinical studies on surgical treatment of OLTs. Screening was performed by 2 reviewers, who subsequently graded the quality using the methodological index for non-randomized studies (MINORS). The primary outcome was the frequency and qualitative assessment of reporting of size, morphology, and location.

RESULTS

Of 3,074 articles, 262 articles were included. This comprised a total of 11,785 patients. Size was reported in 248 (95%) of the articles and was described with a measure for surface area in 83%, however, in 56%, definition of measurement is unknown. Intraclass coefficient (ICC) value for the reliability of size measurement was 0.94 for computed tomography (CT) scan and 0.87 for MRI scan. Morphology was reported in 172 (66%) of the articles and using a classification system in 23% of the studies. Location was reported in 220 (84%) of the studies.

CONCLUSION

No consensus was found on the reporting of morphology, with non-validated classification systems and different terminologies used. For location, reporting in 9 zones is underreported. Size was well reported and measurements are more reliable for CT compared with MRI. As these prognostic factors guide clinical decision-making, we advocate the development of a standardized and validated OLT classification to reach uniform reporting in literature.

LEVEL OF EVIDENCE

Level III, systematic review.

Acute ankle injuries: association between sprain severity and ancillary findings

Miranda et al. reported a correlation between the significance of injuries to osseous, chondral, tendon, and ligamentous tissues in participants with low-grade versus high-grade acute ankle sprains. They demonstrated that participants with high-grade ankle sprains presented with shorter calcaneonavicular distances and increased rates of structural abnormalities compared to those with low-grade sprains. Special attention should be paid to acute ankle sprains in emergency settings to avoid failure in detecting severe injuries that could lead to chronic pain, impairment, or instability. Participants presenting acute ankle sprains (<15 days) were divided into low-grade versus high-grade sprain,according to the presence of a complete tear in at least one component of lateral ligament complex. High-grade ankle sprains group presented increased rates of medial malleolus bone bruise, deltoid ligament tears,extensor retinaculum lesions, and articular effusion. The calcaneonavicular distance was statistically shorter in patients with high-grade sprains (median, 3.0mm) when compared to those with low-grade sprains (median, 4.0mm) Objective: To correlate the significance of osseous, chondral, tendon, and ligamentous injuries with anatomical variations in low-grade versus high-grade acute ankle sprains.

METHODS

We retrospectively identified the magnetic resonance imaging findings of acute ankle sprains (<15 days). Participants with a history of previous sprains, arthritis, tumors, infections, or inflammatory conditions were excluded. Images were independently evaluated by two musculoskeletal radiologists and assessed for osseous, chondral, tendon, and ligamentous injuries and anatomical variations. Participants were divided into low-grade versus high-grade sprain groups, according to the presence of a complete tear in at least one component of the lateral ligament complex.

RESULTS

The final study group comprised 100 magnetic resonance images (mean age, 36 years), the majority of males (54%), the right ankle (52%), and a mean sprain duration of 5 days. Participants with high-grade sprains presented with increased rates of medial malleolus edema (p<0.001), moderate and large articular effusions (p=0.041), and shorter calcaneonavicular distance (p=0.008). Complete tears of the anterior talofibular ligament and calcaneofibular ligaments were observed in 100% and 51.2% of the participants in the High-Grade Group, respectively. The deltoid ligament complex was partially torn in this group (55.8% versus 8.8%, p<0.001). Extensor tendon retinaculum lesions occurred significantly more frequently in this group (41.9%) compared to the overall study population (23%) (p<0.001).

CONCLUSION

Participants with high-grade ankle sprains presented with shorter calcaneonavicular distances and increased rates of medial malleolus edema, deltoid complex partial tears, extensor retinaculum lesions, and articular effusion.

Osteochondral lesions of the talar dome

Ankle pain and/or instability is a frequent, non-specific reason for consultation, and may reveal an osteochondral lesion of the talar dome (OLTD). There are 2 types of OLTD: (1) posteromedial, usually idiopathic, wide and deep, featuring isolated pain with severe functional impact; (2) anterolateral, often implicating trauma and associated in 30% of cases with lateral ligament involvement, in a clinical presentation associating pain and instability. The aim of the present study was to review the issue of OLTD, with 5 questions: HOW TO ESTABLISH THE DIAGNOSIS, WITH WHAT WORK-UP?: There are no specific clinical signs. A diagnosis of OLTD should be considered in all cases of painful and/or unstable ankle and especially in case of history of sprain. The clinical work-up screens systematically for laxity or associated hindfoot malalignment. CT-arthrography is the gold-standard, enabling morphologic analysis of OLTD. WHAT CLASSIFICATIONS SHOULD BE USED?: CT-arthrography determines length, depth and any cartilage dissection, classifying OLTD in 3 grades. Grade 1 is a lesion<10mm in length and<5mm in depth. Grade 2 is>10mm in length and/or>5mm in depth with intact cartilage around the lesion. Grade 3 is the same as grade 2 but with overlying cartilage dissection. WHAT ARE THE CURRENT TREATMENT INDICATIONS?: After failure of 6 months' well-conducted medical treatment (sports rest, analgesics, physiotherapy), surgical options in France today comprise microfracture in grade 1 OLTD, raising the fragment, freshening the floor of the lesion and fixing the fragment (known as "lift, drill, fill, fix" (LDFF)) in grade 2, and mosaicplasty in grade 3. WHAT ARE THE PROSPECTS FOR FUTURE TREATMENTS AND THEIR ROLES?: Treatments are progressing and improving. Ideal treatment should restore hyaline cartilage to prevent secondary osteoarthritis. Matrix and cell culture techniques need to be validated. WHAT RESULTS CAN BE EXPECTED AND WHAT SHOULD PATIENTS BE TOLD?: Management according to grade secures AOFAS scores≥80/100 in 80% of cases, whatever the grade. Return to sport is feasible in 80% of case, at a mean 6 months. Progression is satisfactory after treatment adapted to the lesion. LEVEL OF EVIDENCE: V, expert opinion.

Comparison of arthroscopic debridement and microfracture in the treatment of osteochondral lesion of talus

Objective

This study was performed to compare the clinical effect of arthroscopic debridement vs. arthroscopic microfracture in the treatment of osteochondral lesions of the talus.

Methods

We retrospectively reviewed patients with osteochondral lesion of talus who were admitted to our hospital from April 2020 to April 2021. The patients were divided into Group A (arthroscopic debridement group, n = 39) and Group B (arthroscopic microfracture group, n = 42), and the intraoperative details in the two groups were analyzed. The American Orthopaedic Foot and Ankle Society (AOFAS) score and visual analogue scale (VAS) score were compared between the two groups before surgery and at the last follow-up.

Results

The postoperative AOFAS score (Group A, 40.9-82.26; Group B, 38.12-87.38), VAS score (Group A, 6.44-3.92; Group B, 6.38-2.05) significantly improved in both groups, but the improvement was significantly greater in Group B than in Group A (P < 0.05). Among all patients, the AOFAS and VAS scores of men aged ≤30 years and patients with a low body mass index (BMI) improved more significantly (P < 0.05).

Conclusion

The arthroscopic microfracture for the treatment of osteochondral lesion of talus is superior to joint debridement in terms of improving ankle function, especially in relatively young men with a relatively low BMI.

Talar Dome Osteochondral Lesions: Pre- and Postoperative Imaging

We suggest a similar approach to evaluating osteochondral lesions of the talar dome both pre- and postoperatively. This review addresses the etiology, natural history, and treatment of talar dome osteochondral lesions with an emphasis on imaging appearances. High-resolution magnetic resonance imaging, ideally combining a small field-of-view surface coil with ankle traction, optimizes visibility of most of the clinically relevant features both pre- and postoperatively.

The effect of talus osteochondral defects of different area size on ankle joint stability: a finite element analysis

BACKGROUND

Osteochondral lesion of the talus (OLT) is one of the most common ankle injuries, which will lead to biomechanical changes in the ankle joint and ultimately affect ankle function. Finite element analysis (FEA) is used to clarify the effect of talus osteochondral defects on the stability of the ankle joint at different depths. However, no research has been conducted on talus osteochondral defect areas that require prompt intervention. In this research, FEA was used to simulate the effect of the area size of talus osteochondral defect on the stress and stability of the ankle joint under a specific depth defect.

METHODS

Different area sizes (normal, 2 mm* 2 mm, 4 mm* 4 mm, 6 mm* 6 mm, 8 mm* 8 mm, 10 mm* 10 mm, and 12 mm* 12 mm) of the three-dimensional finite element model of osteochondral defects were established. The model was used to simulate and calculate joint stress and displacement of the articular surface of the distal tibia and the proximal talus when the ankle joint was in the heel-strike, midstance, and push-off phases.

RESULTS

When OLT occurred, the contact pressure of the articular surface, the equivalent stress of the proximal talus, the tibial cartilage, and the talus cartilage did not change significantly with an increase in the size of the osteochondral defect area when the heel-strike phase was below 6 mm * 6 mm. Gradual increases started at 6 mm * 6 mm in the midstance and push-off phases. Maximum changes were reached when the defect area size was 12 mm * 12 mm. The same patterns were observed in the talus displacement.

CONCLUSIONS

The effect of the defect area of the ankle talus cartilage on the ankle biomechanics is evident in the midstance and push-off phases. When the size of the defect reaches 6 mm * 6 mm, the most apparent change in the stability of the ankle joint occurs, and the effect does not increase linearly with the increase in the size of the defect.

Outcomes of Talar Osteochondral and Transchondral Lesions Using an Algorithmic Approach Based on Size, Location, and Subchondral Plate Integrity: A 10-Year Study on 204 Lesions

The management of transchondral and osteochondral talar lesions has evolved, with microfracturing originally considered the best initial treatment. Despite talar lesions being a tri-dimensional defect, most studies use 2-dimensional parameters to grade them. We propose in this study that tri-dimensional sizing may be more appropriate in evaluation for treatment. The present study evaluated the outcomes of treatment of talar lesions performed by a single surgeon, creating and using an algorithm based on volume, location, and integrity of the subchondral plate. The lesions were classified as "small" (up to 125 mm³), "medium" (125 mm³-1500 mm³), and "large" (>1500 mm³) based upon evaluation of the preoperative magnetic resonance imagining. Location of the lesion was also noted on a 9-region grid pattern of the talar dome. These 3 parameters dictated whether a lesion required microfracturing or retrograde drilling, autogenous or allogenous bone graft, and whether an open versus an arthroscopic approach was required. Over a 10-year period, surgery was performed on 204 lesions. Overall, the average time to return to activity was 7.93 ± 5.00 (range 2-36) months. The average preoperative American Orthopaedic Foot and Ankle score was 76.44 ± 10.98 (range 52-86), and the average postoperative American Orthopaedic Foot and Ankle score was 96.12 ± 3.46 (range 81-100), p = .0001. By using the proposed algorithm, the outcome and return to activity for most patients can be better predicted, regardless of the size or location of the osteochondral lesion. The treatment algorithm implemented in the present investigation yielded overall acceptable results, with only 7 of the 204 lesions needing additional surgery.

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.

Comparing the Efficacy of True-Volume Analysis Using Magnetic Resonance Imaging With Computerized Tomography and Conventional Methods of Evaluation in Cystic Osteochondral Lesions of the Talus: A Pilot Study

Background: Osteochondral lesions of the talus (OLT) often require advanced imaging if they prove to be refractory to preliminary microfracture. Orthopedic surgeons may misinterpret the size and morphology of the OLT when evaluating through conventional methods. The purpose of this study was to evaluate MRI as a modality for calculating true-volumes and compare its utility to that of CT true-volume and conventional methods of measuring lesion size.

METHODS

With IRB approval, an institutional radiology database was queried for patients with cystic OLT that had undergone and failed microfracture and had compatible CT and MR scans between 2011 and 2016. Five lesions, previously analyzed and described in the literature using CT true-volume, were selected. 10 orthopedic surgeons independently estimated the volume of these 5 OLT via standard MRI. Next, 3D reconstructions were created and morphometric true-volume (MTV) analysis measurements of each OLT were generated. The percent change in volumes from CT and MR was compared based upon MTVs determined from 3D reconstructive analysis.

RESULTS

The volume calculated using conventional methods in CT and MR scans grossly overestimated the size by of the OLT by 285-864% and 56-374% respectively when compared to 3D true-volume analysis of those CT and MR scans.

CONCLUSIONS

This study demonstrates that true-volume is more accurate for calculating lesion size than conventional methods. Additionally, when comparing MRI and CT, thin slice CT true-volume is superior to MRI true-volume. True-volume calculation improves accuracy with CT and MRI and should be recommended for use in revision OLT cases.Levels of Evidence: Level III: Case control study.

Sufficient Cartilage for Most Talar Articular Defects Can Be Harvested From the Non-Loadbearing Talus: A Cadaveric Analysis

Purpose

To assess the quantity of morselized cartilage that can be harvested from the non–load-bearing portion of the talus for immediate reimplantation.

Methods

Non–load-bearing talar cartilage was harvested from 5 cadaveric specimens using a standard arthroscopic approach. Cartilage was separated from the talus in maximum dorsiflexion at the junction of the talar head and neck, grasped, and morselized into a graft using a cartilage particulator. The volume of reclaimed cartilage was measured, and the extrapolated area of coverage was compared to average osteochondral lesions of the talus previously reported.

Results

The total yield of cartilage graft following processing that was obtained from 5 ankle joints ranged from 0.3 mL to 2.1 mL with a mean volume of 1.3 ± 0.7 mL, yielding a theoretical 13.2 ± 7.1 cm² coverage with a 1-mm monolayer. While the average size of osteochondral lesions of the talus is difficult to estimate, they may range from 0.5 cm² to 3.7 cm² according to the literature.

Conclusions

This study validated that it is possible to harvest sufficient amount of cartilage for an autologous morselized cartilage graft via a single-stage, single-site surgical and processing technique to address most talar articular cartilage defects.

Clinical Relevance

Particulated cartilage autografts have shown promise in surgical management of cartilage defects. A single-site, single-staged procedure that uses a patient’s autologous talar cartilage from the same joint has the potential to reduce morbidity associated with multiple surgical sites, multistaged procedure, or nonautologous tissue in ankle surgery.

Proposal of a new CT arthrographic classification system of osteochondral lesions of the talus

BACKGROUND

Surgical treatment of osteochondral lesions of the talus (OLT) is warranted if medical treatments fail, achieving good results in around 85% of cases. Numerous classification systems, based on all possible imaging modalities (radiography, MRI, CT scan, scintigraphy, and CT arthrography), have been proposed to guide surgical treatments, but none has proven to be superior. A recent study demonstrated the prognostic value of CT arthrography by accurately describing the subchondral bone plate. A systematic review of the literature has brought new criteria to predict good outcome following bone marrow stimulation surgical techniques: lesions should measure less than 1 centimeter in size and 5 millimeters in depth. Based on these data, we are proposing a new simple, 3-stage CT arthrographic classification system of OLT.

MATERIALS AND METHODS

After a brief overview of the classification, 60 CT-arthrographies of ankles with OLT were organized according to this new CT arthrographic classification system by four surgeons (two juniors and two seniors). Two imaging assessments were performed one month apart. Statistical analysis was performed using the Fleiss' kappa coefficient to determine the inter- and intraobserver agreement.

RESULTS

An excellent inter- and intraobserver agreement was found with overall Fleiss' kappa coefficients of 0.897 and 0.847, respectively.

CONCLUSION

The results of our study showed an excellent inter- and intraobserver agreement for this new CT arthrographic classification system of OLT. The principal advantage of this new classification system, based on the latest data in the literature, is its ability to easily distinguish lesions that are more amenable to bone marrow stimulation techniques.

LEVEL OF EVIDENCE

II.

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.

Finite Element Analysis of the Effect of Talar Osteochondral Defects of Different Depths on Ankle Joint Stability

Background

Talus cartilage injury leads to changes in biomechanics of the ankle joint and ultimately affects ankle joint function, but which talus cartilage defects require surgery is still uncertain. This research used a finite element method to simulate the effect of different depth of talus cartilage defects on the stress and stability of the ankle joint in a certain area.

Material/Methods

A three-dimensional finite element model with different depths of osteochondral defects was created to simulate and calculate joint stress and displacement of the articular surface of the distal tibia and the proximal talus while the ankle joint was in the push-off, midstance, and heel-strike phases.

Results

The equivalent stress of the proximal talus did not change significantly at a defect depth of 1 mm, whereas the equivalent stress of the upper talus increased significantly at a defect depth of ≥3 mm or more, reaching a maximum value at a defect depth of 10 mm. The equivalent stress of the tibial cartilage and the equivalent stress and displacement in the corresponding forces in the midstance phase and heel-strike phase were significantly different from those in the normal group, but the difference in stress in each defect group was not obvious.

Conclusions

The effect of cartilage defects of the talus on biomechanics of the ankle is clear, especially in the midstance and push-off phases. When the defect reaches the subchondral bone (at a depth of 3 mm), the most obvious change in ankle joint stability occurs, and it does not increase linearly with the increase in depth of the defect.

Approaching Foot and Ankle Injuries in the Ambulatory Setting

Foot and ankle injuries account for a significant volume of primary care office visits each year. Given the incidence of injury and concern for long-term sequelae, it is imperative that primary care physicians familiarize themselves with commonly encountered foot and ankle injuries. Coupling a sound understanding of key anatomic structures with an appropriately gathered history can help to quickly narrow the differential diagnosis in this clinical presentation. This article focuses on key elements from the history and physical examination as well as provides a concise review of imaging modalities and recommended treatment strategies.

The Role of 3D Reconstruction True-Volume Analysis in Osteochondral Lesions of the Talus: A Case Series

BACKGROUND

Evaluation and management of osteochondral lesions of the talus (OLTs) often warrant advanced imaging studies, especially in revision or cases with cystic defects. It is possible that orthopedic surgeons may overestimate the size and misinterpret the morphology of OLT from conventional computed tomography (CT), thereby influencing treatment strategies. The purpose of this study was to determine the utility of a novel means to estimate the true-volume of OLTs using 3D reconstructed images and volume analysis.

METHODS

With Institutional Review Board approval, an institutional radiology database was queried for patients with cystic OLTs that failed previous microfracture, having compatible CT scans and magnetic resonance imaging (MRI) between 2011 and 2016. Fourteen patients met inclusion criteria. Of these, 5 cases were randomly selected for 3D CT reconstruction modeling. Ten orthopedic surgeons independently estimated the volume of these 5 OLTs via standard CT. Then 3D reconstructions were made and morphometric true-volume (MTV) analysis measurements of each OLT were generated. The percent change in volumes from CT were compared to MTVs determined from 3D reconstructive analysis.

RESULTS

On average, the volume calculated by conventional CT scanner grossly overestimated the actual size of the OLTs. The volume calculated on conventional CT scanner overestimated the size of OLTs compared to the 3D MTV reconstructed analysis by 285% to 864%.

CONCLUSIONS

Our results showed that conventional measurements of OLTS with CT grossly overestimated the size of the lesion. The 3D MTV analysis of cystic osteochondral lesions may help clinicians with preoperative planning for graft selection and appropriate volume while avoiding unnecessary costs incurred with overestimation.

LEVEL OF EVIDENCE

Level IV, case series.