Osteochondritis dissecans of the ankle. A 20-year follow-up study

Treatment of osteochondral lesions of the talus with microfracture technique and postoperative hyaluronan injection

PURPOSE

The aim of this study is to report the outcomes of the treatment of talar osteochondral lesions with arthroscopic microfracture technique and postoperative intra-articular hyaluronan injection.

METHOD

Fifty-seven patients (29 men, 28 women) with osteochondral lesions of the talus were included in this prospective randomized clinical study between the years 2003 and 2009. The patients were treated with arthroscopic debridement and microfracture technique. Randomly selected 41 patients were injected intra-articular hyaluronan (injection group). The remaining 16 patients did not receive postoperative injection (non-injection group). Assessment of the pain and functional outcomes was performed using the Freiburg and AOFAS ankle/hindfoot scoring systems.

RESULTS

In the injection group, the mean postoperative Freiburg functional and pain scores were significantly higher compared to preoperative functional and pain scores (P < 0.001). Similarly, for the patients in non-injection group, the mean postoperative Freiburg functional and pain scores were significantly higher compared to preoperative functional and pain scores (P < 0.001). The AOFAS functional and pain scores of the patients in the injection group were significantly higher (P < 0.001) postoperatively compared to preoperative scores. Scoring the patients in the non-injection group according to AOFAS system also revealed significantly higher (P < 0.001) postoperative functional and pain scores over preoperative scores. The increase in the postoperative scores was found to be significantly higher in the injection group compared to non-injection group in both Freiburg and AOFAS systems (P < 0.001).

CONCLUSION

Treatment of osteochondral lesions of the talus using microfracture technique significantly improved functional and pain scores postoperatively. Additional treatment with intra-articular hyaluronan injection as an adjunct to microfracture technique may offer better clinical outcomes over microfracture technique alone.

LEVEL OF EVIDENCE

Randomized, controlled trial, Level I.

Osteochondral lesions of the talus: effect of defect size and plantarflexion angle on ankle joint stresses

BACKGROUND

Osteochondral lesions of the talus (OLTs) are a common cause of ankle pain and disability. Current clinical guidelines favor autogenous or allogenic osteochondral grafting procedures for lesions larger than 10 mm in diameter because of increased failure rates in these larger lesions with arthroscopic debridement, curettage, and microfracture. There are currently no biomechanical data nor level I clinical data supporting this size threshold.

PURPOSE

The purpose of this study was to determine the effect of OLT defect size on stress concentration, rim stress, and location of peak stress and whether a threshold defect size exists.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Progressively larger medial OLTs were created (6, 8, 10, and 12 mm) in 8 fresh-frozen cadaveric ankle joints. With a calibrated Tekscan pressure sensor in the tibiotalar joint, an axial load of 686 N was applied, and pressure was recorded in neutral and 15° of plantar flexion with each defect size. Peak stress, contact area, peak and average rim stresses, and location of peak stress were determined.

RESULTS

The distance between peak stress and defect rim was significantly decreased with increasing defect size for lesions of 10 mm and larger. Total tibiotalar contact area was significantly decreased with increasing defect size and with ankle plantar flexion. While peak joint stress and peak rim stress were not affected by defect size or plantar flexion, average rim stress was significantly increased by plantar flexion.

CONCLUSION

Reduction in contact area and shift in the location of peak stress with increasing defect size may contribute to articular cartilage degeneration, pain, and defect enlargement in patients with OLTs. There appears to be a threshold of 10 mm after which the distance between the rim of the defect and the peak stress decreases; however, there is no change in peak stress magnitude with increasing defect size.

CLINICAL RELEVANCE

The location of peak stress in the ankle joint becomes closer to the rim of the defect in OLTs at a threshold of 10 mm and greater in diameter. These data may have implications toward OLT size thresholds for surgical decision making in symptomatic lesions (ie, primary osteochondral transplantation procedure vs curettage and debridement). The ultimate goal is to determine whether there is a threshold defect size for primary osteoarticular graft techniques.

Osteochondral lesion of the talus in homozygous twins--the question of heredity

We present a case of osteochondral lesion of the talus (OLT) in homozygous twins in adolescence occurring with no history of trauma. The aetiology of OLT is discussed.

Osteochondritis dissecans (OCD), an endoplasmic reticulum storage disease?: a morphological and molecular study of OCD fragments

Osteochondritis dissecans (OCD) fragments, cartilage and blood from four patients were used for morphological and molecular analysis. Controls included articular cartilage and blood samples from healthy individuals. Light microscopy and transmission electron microscopy (TEM) showed abnormalities in chondrocytes and extracellular matrix of cartilage from OCD patients. Abnormal type II collagen heterofibrils in "bundles" and chondrocytes with abnormal accumulation of matrix proteins in distended rough endoplasmic reticulum were typical findings. Further, Von Kossa staining and TEM showed empty lacunae close to mineralized "islands" in the cartilage and hypertrophic chondrocytes containing accumulated matrix proteins. Immunostaining revealed: (1) that types I, II, VI and X collagens and aggrecans were deposited intracellulary and (2) co-localization within the islands of types I, II, X collagens and aggrecan indicating that hypertrophic chondrocytes express a phenotype of bone cells during endochondral ossification. Types I, VI and X collagens were also present across the entire dissecates suggesting that chondrocytes were dedifferentiated. DNA sequencings were non-conclusive, only single nucleotide polymorphism was found within the COL2A1 gene for one patient. We suggest that OCD lesions are caused by an alteration in chondrocyte matrix synthesis causing an endoplasmic reticulum storage disease phenotype, which disturbs or abrupts endochondral ossification.

Medial approaches to osteochondral lesion of the talus without medial malleolar osteotomy

The purpose of this study was to determine the area of the talus that can be reached through combined anterior and posterior arthrotomy without medial malleolar osteotomy. Five fresh-frozen cadaver foot-ankle specimens were examined using posteromedial approach and anteromedial approach. We calculated the size of the marked area beginning from the posteromedial corner of the talus in the posteromedial approach and beginning from the anteromedial corner in the anteromedial approach. From the posteromedial talus, we can access 33% of the talus' AP length and 30% of its medial to lateral length through a posteromedial approach. From the anteromedial arthrotomy, 50% of the AP length and 31% of the medial to lateral length can be reached. This leaves approximately 20% that is not accessible. If the osteochondral lesion is within the accessible area through either a posteromedial or anteromedial approach as viewed on MRI/CT, it can be safely reached without a medial malleolar osteotomy.

SPECT/CT imaging in general orthopedic practice

The availability of hybrid devices that combine the latest single-photon emission computed tomography (SPECT) imaging technology with multislice computed tomography (CT) scanning has allowed us to detect subtle, nonspecific abnormalities on bone scans and interpret them as specific focal areas of pathology. Abnormalities in the spine can be separated into those caused by pars fractures, facet joint arthritis, or osteophyte formation on vertebral bodies. Compression fractures can be distinguished from severe degenerative disease, both of which can cause intense activity across the spine on either planar or SPECT imaging. Localizing activity in patients who have had spinal fusion can provide tremendous insight into the causes of therapeutic failures. Infections of the spine now can be diagnosed with gallium SPECT/CT, despite the fact that gallium has long been abandoned because of its failure to detect spine infection on either planar or SPECT imaging. Small focal abnormalities in the feet and ankles can be localized well enough to make specific orthopedic diagnoses on the basis of their location. Moreover, when radiographic imaging provides equivocal or inadequate information, SPECT/CT can provide a road map for further diagnostic studies and has been invaluable in planning surgery. Our ability to localize activity within a bone or at an articular surface has allowed us to distinguish between fractures and joint disease. Increased activity associated with congenital anomalies, such as tarsal coalition and Bertolotti's syndrome have allowed us to understand the pathophysiology of these conditions, to confirm them as the cause of the patient's symptoms, and to provide information that is useful in determining appropriate clinical management. As our experience broadens, SPECT/CT will undoubtedly become an important tool in the evaluation and management of a wider variety of orthopedic patients.

A novel implantation technique for engineered osteo-chondral grafts

We present a novel method to support precise insertion of engineered osteochondral grafts by pulling from the bone layer, thereby minimizing iatrogenic damage associated with direct manipulation of the cartilage layer. Grafts were generated by culturing human expanded chondrocytes on Hyaff-11 meshes, sutured to Tutobone spongiosa cylinders. Through the bone layer, shaped to imitate the surface-contours of the talar dome, two sutures were applied: the first for anterograde implantation, to pull the graft into the defect, and the second for retrograde correction, in case of a too deep insertion. All grafts could be correctly positioned into osteochondral lesions created in cadaveric ankle joints with good fit to the surrounding cartilage. Implants withstood short-term dynamic stability tests applied to the ankle joint, without delamination or macroscopic damage. The developed technique, by allowing precise and stable positioning of osteochondral grafts without iatrogenic cartilage damage, is essential for the implantation of engineered tissues, where the cartilage layer is not fully mechanically developed, and could be considered also for conventional autologous osteochondral transplantation.

Matrix-Induced Autologous Chondrocyte Implantation (MACI) grafting for osteochondral lesions of the talus

BACKGROUND

Articular cartilage is limited in its ability to repair itself. Matrix-induced Autologous Chondrocyte Implantation (MACI) is an established treatment method for such articular cartilage defects in the knee. Recently the technique has been used in the ankle. We present a series of patients treated with MACI for osteochondral defects of the ankle, and assess the functional and clinical results.

MATERIALS AND METHODS

From August 2003 to February 2006, 20 patients underwent MACI grafting for osteochondral defects in the ankle. Age ranged from 19 to 61 (mean, 36) years. Mean followup was 21.1 months. Clinical and functional evaluations were conducted using the AOFAS scoring system.

RESULTS

The mean size was 233 mm(2). There was a significant improvement in mean AOFAS score from 60 (range, 25 to 87) to 87 (range, 41 to 100) (p < 0.0001). Overall improvement in pain scores was also significant (p < 0.0001). All osteotomies healed. Four patients required hardware removal and two underwent arthroscopic debridement for anterior impingement. There were two failures which are awaiting subsequent procedures.

CONCLUSION

We believe MACI is a reliable treatment method for talar osteochondral defects. The method usually requires an intra-articular osteotomy, although this proved to be a reasonably simple aspect of the procedure for the treatment of cartilage defects of the talus.

Treatment of a distal tibial osteochondral lesion with a synthetic osteochondral plug: a case report

Level of Evidence: V, Expert Opinion

Osteochondrosis dissecans of the medial malleolus: a case report

Osteochondrosis dissecans of the ankle accounts for approximately 4% of all osteochondrosis dissecans. Most osteochondrosis dissecans in the ankle is found in the talar dome. We report the case of osteochondrosis dissecans of the medial malleolus in a 46-year-old patient which has not been described yet.

Osteochondral lesions of the distal tibial plafond: localization and morphologic characteristics with an anatomical grid

BACKGROUND

The aim of this study was to evaluate the incidence and morphologic characteristics of osteochondral lesions of the distal tibial plafond (OLTP) by location and morphologic characteristics on MRI.

MATERIAL AND METHODS

We assigned 9 zones to the distal tibial plafond articular surface in an equal 3 x 3 grid configuration. Zone 1 was the most anterior and medial, zone 3 was anterior and lateral, zone 7 was most posterior and medial, and zone 9 was the most posterior and lateral. The grid was designed with all 9 zones being equal in surface area. Two observers reviewed MRI examinations of 38 patients (12 males and 26 females; mean age, 38.7 years; age range, 10 to 68 years) with reported OLTPs. We recorded the frequency of involvement and size of lesion for each zone. A chart review was performed.

RESULTS

Of the 38 OLTP found in this study, 14 (37%) of the lesions were on the medial tibial plafond [zones 1, 4 and 7] and 11 (29%) involved the lateral tibial plafond [zones 3, 6 and 9]; 13 lesions (34%) localized to the center third of the plafond [zones 2, 5 and 8]. Nine of the lesions (24%) were on the anterior tibial plafond [zones 1, 2 and 3], 15 lesions (39%) predominately involved the posterior plafond [zones 7, 8 and 9], and 14 lesions (37%) localized to the central third of the plafond [zones 4, 5 and 6]. The medial central tibial plafond was most frequently involved site with 8 of the 38 (21%) lesions located there; the posterior medial tibial plafond was second most frequently involved with six of the 38 lesions (16%). Six of 38 ankles had both a talar osteochondral lesion and an OLTP. Of these, only one was a ;kissing' lesion. Chart review revealed that all subjects had ankle pain at time of MRI examination.

CONCLUSION

We conclude that osteochondral lesions of the distal tibial plafond must be considered in the differential diagnosis of patients with symptomatic ankles and that no location had a significantly higher incidence.

A review of osteochondral lesions of the talus

This article provides an in-depth overview of the most current information.

Treatment of osteochondritis dissecans of the ankle with hyaluronic acid injections: a prospective study

BACKGROUND

No studies have evaluated the efficacy of hyaluronic acid (HA) in reducing pain caused by osteochondritis dissecans (OCD) of the ankle. We report our initial results with this treatment.

MATERIALS AND METHODS

Fifteen subjects aged 18 to 60 treated for OCD of the talus were followed for 26 weeks, in a pre- and post-treatment repeated measurements design, after receiving three weekly injections of intra-articular HA. The efficacy of HA injections in reducing pain and improving function was assessed at each visit and adverse events were recorded. Efficacy was evaluated by comparing scores determined using a Visual Analog Scale for pain, stiffness and function over time with baseline values. In addition, frequency of symptoms and global function over time were assessed using questionnaires and the AOFAS Ankle-Hindfoot Scale. Data analysis was made using ANCOVA models and paired t-tests. All statistical tests were based on an alpha level of 0.05.

RESULTS

The majority of subjects were male (60%) and had Grade 3 lesions (60%). Mean VAS scores, reported on a scale from 1 (e.g., no pain) to 10 (e.g., worst pain) decreased for pain (5.6 to 3.2), stiffness (5.1 to 2.9), and function (5.9 to 3.3) from baseline to week 26. Subjective global function scores, reported on a scale from 0 to 100 (with 100 representing healthy, pre-injury function), improved on average from 57.3 at baseline to 74.3 by week 26. All of these results were statistically significant, as was the decrease in frequency of pain reported by subjects at the end of the study.

CONCLUSION

OCD of the ankle treated with intra-articular injections of HA caused a decrease in pain scores and increase in global functioning over a short period of time (within 12 weeks) which then lasted for more than 6 months with minimal adverse events.

Arthroscopic treatment of chronic osteochondral lesions of the talus: long-term results

BACKGROUND

Osteochondral lesions of the talus are relatively uncommon but may be a cause of significant pain and disability in symptomatic patients.

HYPOTHESIS

Arthroscopic treatment of osteochondral lesions of the talus will result in good long-term clinical outcomes in the majority of patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Fifty patients with chronic osteochondral lesions of the talus underwent arthroscopic treatment. Average age was 32 years (range, 12-72 years). Average follow-up was 71 months (range, 24-152 months). Treatment consisted of either drilling of the osteochondral lesions of the talus in situ (n = 4), excision of the osteochondral lesions of the talus and abrasion arthroplasty (n = 6), or excision of the osteochondral lesions of the talus and drilling (n = 40). Preoperative and intraoperative staging of the osteochondral lesions of the talus was performed. Follow-up evaluation included 3 clinical rating systems: Alexander, modified Weber, and American Orthopaedic Foot and Ankle Society Ankle/Hindfoot scores.

RESULTS

There were 72% excellent/good, 20% fair, and 8% poor results on the Alexander scale. According to the modified Weber scale, there were 64% excellent/good, 30% fair, and 6% poor results. The average American Orthopaedic Foot and Ankle Society Ankle/Hindfoot score was 84 (range, 34-100). We found no correlation between plain radiographs, computed tomography, or magnetic resonance imaging staging and clinical results. However, there was significant correlation between arthroscopic stage and clinical outcome. Seventeen patients had been seen 5 years previously and evaluated using the same criteria; 35% demonstrated a deterioration in their result over time.

CONCLUSION

Arthroscopic treatment of chronic symptomatic osteochondral lesions of the talus results in good clinical outcomes in the majority of patients. However, pain and functional limitation may persist in some patients, especially those noted to have unstable osteochondral defects at the time of arthroscopy.

Arthroscopic treatment of osteochondral lesions of the distal tibia

BACKGROUND

Osteochondral lesions of the tibia are much less frequent than those of the talus, and treatment guidelines have not been established. We hypothesized that arthroscopic treatment methods used for osteochondral lesion of the talus would also be effective for those of the distal tibia.

METHODS

A review of 880 consecutive ankle arthroscopies identified 23 patients (2.6%) with osteochondral lesions of the distal tibia. Four patients were excluded because of concomitant acute ankle fractures requiring open reduction and internal fixation and two were lost to followup, leaving 17 in the study. The mean age was 38 (19 to 71) years. Six (35%) had osteochondral lesions of the tibia and talus; 11 had isolated lesions of the distal tibia. Treatment included excision, curettage, and abrasion arthroplasty in all patients. Five patients had transmalleolar drilling of the lesion, two had microfracture, and two had iliac bone grafting. At last followup, patients were evaluated with a questionnaire, physical examination, and ankle radiographs.

RESULTS

Mean followup was 44 (24 to 99) months. Preoperatively, the median American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score was 52; postoperatively, it was 87. Using the Wilcoxon signed-rank test to compare preoperative and postoperative scores, there was significant improvement in the ankle-hindfoot score postoperatively (p < 0.001). Seven patients had excellent results, seven had good results, one had a fair result, and two had poor results.

CONCLUSIONS

Osteochondral lesions of the distal tibia present a challenge to the orthopedic surgeon. Arthroscopic treatment by means of debridement, curettage, abrasion arthroplasty, and, in some patients, transmalleolar drilling, microfracture, or iliac crest bone grafting, resulted in excellent and good results in 14 of 17 patients at medium-term followup.

Histological and cell biological characterization of dissected cartilage fragments in human osteochondritis dissecans of the femoral condyle

INTRODUCTION

Osteochondritis dissecans (OCD) within the weight-bearing femoral condyle carries a high risk of osteoarthritis. The definitive pathogenetic cause is unclear. Therefore biochemical and cellular features of OCD were analyzed and compared to macroscopically normal cartilage of the same joint surface.

MATERIALS AND METHODS

Dissected fragments from 14 patients and biopsies of normal cartilage from the intercondylar notch as controls were harvested at arthroscopy. Staining with safranin O to monitor proteoglycan content, alkaline phosphatase activity, and immunohistochemistry with mouse monoclonal antibodies to collagen types I, II, and X. Chondrocytes were isolated for RT-PCR to detect GAPDH, collagen types I, II, X, aggrecan, TGF-beta, BMP-7, bFGF, VEGF and IL-1.

RESULTS

The dissected cartilage displayed significant variability. Apart from normal cartilage matrix components also atypical molecules such as collagen type X and alkaline phosphatase were detected at the tidemark but also across the entire dissecate, suggesting chondrocyte hypertrophy. Extended fibrous degeneration associated with collagen type I deposition was observed at the surface and may indicate chondrocyte dedifferentiation. Viable cells could be extracted from OCD and notch. Both expressed similar mRNA levels for matrix molecules, growth factors, and interleukin-1 (IL-1), however significantly more Col X mRNA was detected in dissecates.

CONCLUSION

Histology suggests focal alteration of cartilage matrix originating from the basis of the joint cartilage, potentially the mineralized layer or subchondral bone. The molecular analysis indicates a disorganization of cartilage homeostasis across the joint accompanied by embryogenetic processes. The surprisingly high viability and quality of the extracted cells suggests a still preserved intrinsic repair capacity of those vital dissecates.

Osteochondral lesions of the talus: change in MRI findings over time in talar lesions without operative intervention and implications for staging systems

BACKGROUND

MRI findings are used in several staging systems to help determine appropriate treatment. The purposes of this study were to evaluate longitudinal changes in MRI characteristics of osteochondral lesions of the talus (OLT) and to evaluate published staging systems in a cohort of nonoperatively treated patients.

METHODS

Twenty-nine patients were identified; MR images were reviewed for location, size, and interface signal of OLT as well as cysts, marrow edema and osteoarthritis. Lesions were classified as unchanged, progressed, or improved based on changes in size or interface signal. Each lesion was assigned a stage based on four different staging systems.

RESULTS

Of the 29 lesions, 13 progressed, seven improved, and nine were unchanged over an average followup of 13.7 months. In the 13 that progressed, marrow edema remained present in ten and developed in two. Four had persistent cysts and four developed new cysts. Two had progression of osteoarthritis and two developed it anew. In the seven that improved, six had some degree of marrow edema that persisted and one had a persistent cyst. Initial staging changed for at least one classification system in 16 (55%) of the 29 lesions at followup. Change in stage was primarily due to development (four of 16) or disappearance of cysts or progression of the lesion in the extent of bone marrow edema (five of 16).

CONCLUSIONS

OLT did not invariably progress over the short-term without operative intervention. Because some cysts and bone marrow edema resolved on MRI, they may not be reliable signs of lesion severity nor show progression of degenerative changes. Since these findings determine the stage and severity of OLT in some staging systems, they may require reconsideration and adjustment of the current staging systems.

Early results of autologous chondrocyte implantation in the talus

Autologous chondrocyte implantation (ACI) has been used most commonly as a treatment for cartilage defects in the knee and there are few studies of its use in other joints. We describe ten patients with an osteochondral lesion of the talus who underwent ACI using cartilage taken from the knee and were prospectively reviewed with a mean follow-up of 23 months. In nine patients the satisfaction score was 'pleased' or 'extremely pleased', which was sustained at four years. The mean Mazur ankle score increased by 23 points at a mean follow-up of 23 months. The Lysholm knee score returned to the pre-operative level at one year in three patients, with the remaining seven showing a reduction of 15% at 12 months, suggesting donor-site morbidity. Nine patients underwent arthroscopic examination at one year and all were shown to have filled defects and stable cartilage. Biopsies taken from graft sites showed mostly fibrocartilage with some hyaline cartilage. The short-term results of ACI for osteochondral lesions of the talus are good despite some morbidity at the donor site.

Cartilage restoration, part 2: techniques, outcomes, and future directions

In part 1 of this 2-part Current Concepts article, the authors reviewed the basic science of normal articular and meniscal cartilage and its response to injury. They reviewed the historical perspectives and basic science behind these various methods and presented a rationale for patient evaluation, treatment selection, and timing. In part 2, the authors review the specific indications for the treatment of chondral injuries and describe the techniques and outcomes of the various treatment options, including palliative, reparative, and restorative procedures. In addition, they will examine specific complex clinical scenarios emphasizing treatment options of comorbid conditions including ligament instability, meniscal deficiency, and malalignment. A limited review of the application of these techniques in joints other than the knee will also be presented. A conceptual algorithm is developed to assist in clinical decision making.

Impact of high field (3.0 T) magnetic resonance imaging on diagnosis of osteochondral defects in the ankle joint

OBJECTIVE

To evaluate high field magnetic resonance (MR) imaging for imaging of osteochondral defects.

MATERIALS AND METHODS

Nine osteochondral defects were simulated in three cadaveric talus specimens using a diamond drill. All specimens were examined on a 1.0 T MR unit and a 3.0 T MR unit. A T2-weighted turbo spin-echo (TSE) sequence with a 2 mm slice thickness and a 256 x 256 matrix size was used on both scanners. The visibility of the osteochondral separation and the presence of susceptibility artifacts at the drilling bores were scored on all images.

RESULTS

Compared to the 1.0 T MR unit, the protocol on the 3.0 T MR unit allowed a better delineation of the disruption of the articular cartilage and a better demarcation of the subchondral defect. Differences regarding the visualization of the subchondral defect were found to be statistically significant (P<0.05). Differences with regard to susceptibility artifacts at the drilling bores were not statistically significant (P>0.05). The average SNR was higher using 3.0 T MRI (SNR=12), compared to 1.0 T MRI (SNR=7).

CONCLUSION

High field MRI enables the acquisition of images with sufficient resolution and higher SNR and has therefore the potential to improve the staging of osteochondral defects.

Operative treatment of osteochondral lesions of the talar dome: current concepts review

Osteochondral lesions of the talar dome are common problems encountered in orthopaedics. Procedures for the treatment of osteochondral lesions of the talus, including debridement of the joint, shaving of fibrillated cartilage, and resection or perforation of subchondral bone in the last decade, have been performed arthroscopically with very low morbidity. These seem to be inadequate in lesions larger than 1.5 cm(2) and have not been histologically effective in restoring the hyaline cartilage sheath. Osteochondral allografts or autogenous grafts and autologous chondrocyte transplantation have proven to be capable of restoring the articular hyaline cartilage surface, including defects larger than 2 cm(2), although with higher costs and morbidity. In this review, the aforementioned methods of operative treatment are examined and issues that are related to these methods are discussed.

Adolescent osteochondral lesion of the talus. Ankle arthroscopy in pediatric patients

Osteochondral lesions of the talus can be difficult to diagnose and can result in a significant functional limitation in young, active patients. New imaging modalities have improved the diagnosis and staging of these lesions. In general, nonoperative treatment results in poorer outcomes compared with operative treatment, and arthroscopic treatment has results similar to open treatment. Although the literature is limited, the treatment of adolescents results in outcomes similar to the adult population.

Nonoperatively managed stage 5 osteochondral talar lesions

Thirty-five ankles in 34 subjects with non-surgically managed stage 5 (chronic) osteochondral lesions of the talus (OLT) were reassessed an average of 38 months post diagnosis--88 months post symptom onset. The overall clinical result was rated good or excellent in 54%, fair in 17% and poor in 29%. Six patients opted for surgery--arthroscopic drilling--after a trial of one year of nonsurgical treatment and were therefore rated as poor. Tomogram or CT scans at the time of diagnosis and follow-up were compared in 25 patients. We found no significant change in lesion size and there was a poor correlation between change in lesion size and clinical outcome. X-rays performed at follow-up on 20 patients showed mild degenerative changes in 13 of 20 ankles with OLT. No correlation was found between the presence of degenerative changes and the clinical outcome. We conclude that: 1. Non-surgical management of stage 5 OLT is a viable option with little or no risk of developing significant osteoarthritis. 2. Most lesions remain radiographically stable. 3. There is a poor correlation between changes in lesion size and clinical outcome. However, the few patients with lesions which decrease significantly in size tend to do well and those with lesions which increase significantly in size do poorly. 4. The development of mild radiographic changes of OA does not correlate with clinical outcome. 5. The general course of stage 5 OLT is benign with over half of the patients improving to good or excellent results with non-surgical management. 6. Lateral lesions tend to do better than medial ones. 7. Adult onset lesions tend to do better than juvenile onset lesions.

Mosaicplasty of the talus: a joint contact analysis in a cadaver model

Treating large osteochondral defects of the talar dome is a challenging problem for the foot and ankle surgeon. The purpose of this study was to determine if ankle joint surface mechanics can be restored by repairing large osteochondral defects with multiple osteochondral cylinder grafts. Pressure-sensitive film was used to measure total contact area and mean contact pressure of the ankle joint using a cadaver foot model. Specimens were sequentially tested evaluating the following conditions: 1) intact ankle, 2) with osteochondral defect, and 3) after mosaicplasty. An ovoid chondral defect measuring 8 x 12 mm for each specimen was consistently placed within the center of the contact zone. Multiple osteochondral grafts were harvested from donor tali and placed in the defect. Two graft arrays arranged in either a cluster of four 4 x 10 mm or two 6 x 10 mm plugs were inserted sequentially to fill the defect and were tested separately. Specimens were positioned in a neutral alignment on a custom load frame and axially loaded to 560 N with the pressure transducer in place. The transducers were then digitized and analyzed with an imaging software program. Data for total contact area and mean contact pressures for all conditions of each specimen were collected and statistically analyzed. Results demonstrated that the 6-mm grafts were less than optimal in fully restoring the defect in the contact zone of the talus. There was significant decrease in mean total contact area and increase in contact zone mean pressure compared to the intact condition (p < .05). Whereas, 4-mm plugs nearly restored joint contact area and pressure to normal levels. These findings suggest that focal talar dome defects can be repaired to restore normal ankle contact characteristics via the placement of small, osteochondral cylindrical grafts of talar origin.

Autologous chondrocyte transplantation for osteochondritis dissecans of the talus

Eight patients with osteochondritis dissecans of the talus were reviewed. The average followup was 17.6 months (range, 8-26 months). The mean age of the patients was 31.8 years (range, 22-42 years). All patients had a preoperative examination, magnetic resonance imaging, and radiologic classification of the lesion through regular anteroposterior and lateral radiographs. Diagnostic arthroscopy and biopsies of healthy cartilage were done, which then had chondrocyte extraction and culture. After an average of 2.5 weeks, an arthrotomy, malleolar osteotomy, subchondral bone sclerosis debridement, and autologous chondrocyte transplantation were done. The postoperative treatment included nonweightbearing for 6 to 7 weeks, physiotherapy, and continuous passive motion. According to the postoperative evaluation score, all results were excellent to good with an average score of 0.6. No complications occurred. The arthroscopic reexamination of three patients at the sixth postoperative month and the radiologic evaluation of all patients showed the existence of cartilagelike tissue with complete coverage of the chondral defect. This method enables reconstructive intervention for unicompartmental defects of articular cartilage through implantation of new chondrocytes, establishment of a subchondral blood supply, and reconstruction of the articular surface.

Bilateral distal tibial osteochondral lesion: a case report

Osteochondral lesion of the talar dome is a well-known clinical and radiographic entity. Less known is osteochondral lesion of the articular surface of the distal tibia. A case report, which demonstrates bone-scintigraphy and MRI findings of bilateral osteochondral lesion of tibial plafond and related literature, is presented.

Pediatric foot fractures: evaluation and treatment

Foot fractures account for 5% to 8% of all pediatric fractures and for approximately 7% of all physeal fractures. A thorough understanding of the anatomy of the child's foot is of central importance when treating these injuries. Due to the difficulties that may be encountered in obtaining an accurate physical examination of a child with a foot injury and the complexities of radiographic evaluation of the immature foot, a high index of suspicion for the presence of a fracture facilitates early and accurate diagnosis. Although the treatment results in pediatric foot trauma are generally good, potential pitfalls in the treatment of Lisfranc fractures, talar neck and body fractures, and lawn mower injuries to the foot must be anticipated and avoided if possible.

Osteochondral defects of the talus treated with fresh osteochondral allograft transplantation

Between 1980 and 1996, 9 patients with osteocartilagenous lesions of the talus were treated surgically using fresh osteochondral allograft transplantation. In 8 cases the reason for surgery was osteochondritis dissecans (4 of these cases had a previous traumatic injury). In 1 case a fresh osteochondral allograft of the talus was required following a traumatic open fracture of the talus sustained in a motor vehicle accident. Of these 9 grafts, 6 grafts remain in situ with a mean survival of 11 years (range 4 to 19). In the three cases requiring fusion the reason for surgery was not related to arthritic deterioration but due to resorption and fragmentation of the graft.

Osteochondral injuries. Clinical findings

Osteochondral injuries are common, mainly affecting a young, active population. Failure to recognize these injuries can lead to long-term disability. A heightened awareness and understanding of the common mechanisms of injury will lead to early diagnosis and rapid recovery. This, along with improved treatment modalities, will keep any long-term disability to a minimum.

Osteochondritis dissecans of the tibial plafond: imaging characteristics and a review of the literature

OBJECTIVE; Osteochondritis dissecans of the talar articular surface of the ankle joint has been well described. We report the imaging characteristics of osteochondritis dissecans of the tibial articular surface (tibial plafond).

CONCLUSION

Osteochondritis dissecans of the tibial plafond is a rare condition that may not be detectable on radiography. Its radiologic findings are similar to those of osteochondritis dissecans located elsewhere in the body.

Arthroscopy of the ankle: analysis of results and indications on a series of 75 cases

The purpose of this study was to evaluate the results of arthroscopy of the ankle. Of the 114 arthroscopies of the ankle that we performed between 1991 and 1996, 13 were for diagnosis, 6 were associated with open surgery, and 10 were ankle arthrodeses. We report the results of the remaining 85 therapeutic arthroscopies. We identified five groups according to preoperative indications: (1) anterolateral synovitis after a sprained ankle (33 cases), (2) sequelae of fractured ankles (17 cases), (3) anterior impingement as a result of osteophytes (12 cases), (4) loose foreign bodies as a result of avulsion of fragments of bone (6 cases), and (5) osteochondral lesions of the talar dome (17 cases). In anterolateral synovitis, results were better when the pain followed a single sprain than when after chronic instability. In osteochondral lesions of the talar dome, results were better in anterolateral lesions than in posteromedial lesions.

Arthroscopic drilling for the treatment of osteochondral lesions of the talus

BACKGROUND

An osteochondral lesion of the talus is a relatively rare disorder of the ankle. While a number of treatment options have been reported, it appears to be difficult to manage all lesions with a single approach. We evaluated the indications for and the results of arthroscopic drilling for the treatment of an osteochondral lesion of the talus.

METHODS

Eighteen ankles (seventeen patients) with a symptomatic osteochondral lesion of the talus were examined. The ages of the patients ranged from ten to seventy-eight years (mean, 28.0 years) at the time of the operation, and the patients were followed postoperatively for two to 9.5 years (mean, 4.6 years). After the continuity of the cartilage overlying the lesion and the stability of the lesion had been confirmed, arthroscopic drilling was performed with use of a Kirschner wire that was 1.0 to 1.2 millimeters in diameter. A cast was not applied postoperatively, and full weight-bearing was allowed six weeks after the procedure.

RESULTS

The clinical result was good for thirteen ankles and fair for five; all ankles had improvement. Twelve of the thirteen ankles that were in patients who were less than thirty years old had a good result. In contrast, only one of the five ankles in patients who were fifty years old or more had a good result. Thus, the clinical results tended to be better for younger patients. Improvement was seen radiographically in fifteen ankles. However, the three ankles in patients who were more than sixty years old were found to have no improvement on radiographic examination. Analysis of the group of patients who had a history of trauma revealed that the mean interval between the injury and the operation was 6.3 months for the three ankles that had a good radiographic result and 11.3 months for the six that had a fair result. Thus, the radiographic results tended to be better when the interval between the injury and the operation was shorter.

CONCLUSIONS

Arthroscopic drilling for the treatment of medial osteochondral lesions of the talus does not require osteotomy of the medial malleolus or postoperative immobilization; thus, the procedure is less invasive than other types of operative treatment for the condition and it allows early resumption of daily activities and sports. On the basis of the results in this study, we believe that the procedure is effective and useful in young patients, especially those who have not yet had closure of the epiphyseal plate. A specific indication for the procedure is an early lesion with only mild osteosclerosis of the surrounding talar bone, continuity of the cartilaginous surface, and stability of the osteochondral fragment.

Treatment of unstable osteochondritis dissecans lesions of the knee using autogenous osteochondral grafts (mosaicplasty)

Symptomatic osteochondritis dissecans lesions with minimal fragmentation that may be replaced within their crater have classically been treated by reattachment. The choice for internal fixation is varied. This article reports on the treatment of unstable osteochondritis dissecans lesions using autogenous osteochondral plugs as a means of biological internal fixation. The appearance on magnetic resonance imaging of osteochondral plugs at 6 and 9 months after transplantation is also presented.

Osteochondrosis of the canine tibiotarsal joint

This article reviews previous literature and current conclusions regarding osteochondrosis dissecans in the canine tarsus since it was first reported only 20 years ago. Breed, signalment, and clinical characteristics can greatly aid the clinician in suspicion of this condition. Specific radiographic techniques for confirmation of osteochondrosis are discussed. Treatment options, expectations, and specific surgical approaches are reviewed.

Osteochondral lesions of the talar dome

Osteochondral lesions of the talar dome are a common cause of ankle disability. Management options are as numerous as the terms used to describe these lesions. The recognition of a traumatic etiology has increased our understanding and management of these disorders. Modern imaging technology has enhanced the ability to fully evaluate and accurately classify this lesion, which is fundamental for proper treatment.

Osteochondrosis dissecans of the talus. Comparison of results of surgical treatment in adolescents and adults

Clinical results in two groups of patients treated for osteochondrosis dissecans tali were examined in a follow-up examination: adolescents up to age 16 years versus adults. Thirteen patients were reexamined in each group. Clinical comparison revealed distinct differences between the groups. In adolescents there were eight excellent and three good results, only one fair, and one poor result. In contrast, adults demonstrated excellent results in only two and good results in five patients; five patients showed fair results and one a poor outcome. No signs of osteoarthrosis were detected in adolescents whereas in four adult patients slight radiological signs of osteoarthritis were visible. In both groups clinical and radiological results were better when the cartilage layer at the talar dome was found to be intact at the time of surgical intervention. Detectable cartilage damage at the time of operation was accompanied by a worse result at the time of follow-up examination. In conclusion, adolescents without any signs of joint locking or loose body formation should first be treated conservatively. The older the patient the shorter the period of nonsurgical treatment should be. In cases of increasing stages, joint locking, or formation of loose bodies surgical intervention is recommended.

Demonstration of osteochondritis dissecans of the talus by coronal computed tomographic arthrography

Ten cases of osteochondritis dissecans of the talus are reviewed. Coronal computed tomographic arthrography identified the precise location in each case and consistently revealed the extent of the lesion to be greater than that apparent on the plain radiographs. The talar cartilage over the lesion was shown to be thinned in four cases, deficient in two, and fissuring of the cartilage was demonstrated in four. Subarticular cysts were identified in all but two cases and contrast medium was shown to enter the cysts in two cases indicating a communication with the ankle joint. The aetiology and relevance of these findings to treatment are discussed.