Ultrasound properties of articular cartilage immediately after osteochondral grafting surgery: in cases of traumatic cartilage lesions and osteonecrosis

Although osteochondral grafting surgery is believed to replace damaged cartilage with healthy-looking normal cartilage, no study focuses on ultrasound quantification of those cartilage immediately after the surgery. It is unknown whether the ultrasound properties of damaged cartilage from trauma or osteonecrosis are same with each other. We have examined ultrasound properties of damaged cartilage, adjacent intact cartilage and plug cartilage during osteochondral grafting surgery for 15 knees of 15 patients, mean age of 43.4 (range, 14–61) years. Results showed that signal intensities of ultrasound (a measure of superficial cartilage integrity) of intact cartilage, damaged cartilage, and plug cartilage were 1.91 (arbitrary unit), 0.40, and 2.13, respectively, in 11 knees of 11 patients of traumatic cartilage lesions. Interval between signals of ultrasound (a parameter related to thickness) were 2.79 (μs), 1.90, and 2.85, respectively. The signal intensity and the interval between signals of plug cartilage were 533% (P < 0.01) and 150% (P < 0.01) of damaged cartilage, respectively. In four knees of four patients of osteonecrosis, the signal intensities of intact cartilage, damaged cartilage, and plug cartilage were 1.25, 0.30, and 1.39, respectively. The interval between signals were 2.36, 2.00, and 2.69, respectively. The signal intensity and the interval between signals of plug cartilage were 463% (P < 0.01) and 135% (P < 0.05) of damaged cartilage. We conclude that ultrasound properties of the damaged cartilage from trauma or osteonecrosis did not differ a lot especially in the late stages of osteonecrosis and that the osteochondral grafting surgery replaced the damaged cartilage with plug cartilage that had greater superficial cartilage integrity and greater thickness parameter immediately after the surgery. Long-term effect of the osteochondral grafting surgery should be verified in further study.     

Hybrid fixation: evaluation of a novel technique in adult osteochondritis dissecans of the knee

Purpose  

Treatment of osteochondritis dissecans of the adult knee requires bone and cartilage integration of the loose fragment. Screw fixation provides primary stability but does not guarantee bony consolidation. Additional biological fixation using osteochondral grafts—hybrid fixation—could improve fragment integration.     

Fluoro-Free navigated retrograde drilling of osteochondral lesions

Purpose  

Retrograde drilling of osteochondral lesions (OCLs) is a recommended, but demanding operative approach for revascularization of lesions in stage 1–3 according to Berndt and Harty after failed conservative treatment. The gold standard of intraoperative driller guidance is fluoroscopic control. Limitations are a 2D visualization of a 3D procedure and sometimes limited view of the OCL in fluoroscopy, leading to increased radiation exposure. A new image-free navigation procedure was evaluated for practicability and precision in first clinical applications.     

High-resolution MR imaging of talar osteochondral lesions with new classification

Purpose  

Retrospective review of high-resolution MR imaging features of talar dome osteochondral lesions and development of new classification system based on these features.     

Role of arthroscopic microfracture for cystic type osteochondral lesions of the talus with radiographic enhanced MRI support

Purpose  

Comparatively little literature is available on treatment evaluations of individual osteochondral lesions of the talus (OLT), such as cystic type OLT. It is also noteworthy that controversy still exists regarding the best primary treatment option for cystic type OLT. The purpose of this study was to evaluate the clinical outcomes of arthroscopic microfracture of symptomatic cystic type OLT, irrespective of lesion size, and to verify the efficacy of enhanced ankle MRI for predicting the nature of cystic osteochondral lesions.     

Platelet-rich plasma activation in combination with biphasic osteochondral scaffolds–conditions for maximal growth factor production

Purpose  

The combination of scaffolds and biological factors may enhance articular cartilage repair. Little is known regarding the activation and subsequent growth factor release of platelet-rich plasma (PRP) in contact with biosynthetic scaffolds. The purpose of this study was i) to identify whether the addition of thrombin was required to activate PRP in the presence of a collagen osteochondral scaffold and ii) to compare the activity of PRP when applied to both collagen- and polylactide-based osteochondral scaffolds.     

Effectiveness and limitations of autologous osteochondral grafting for the treatment of articular cartilage defects in the knee

Purpose  

To evaluate the effectiveness and limitations of autologous osteochondral grafting for the treatment of articular cartilage defects in the knee.     

Scanty integration of osteochondral allografts cryopreserved at low temperatures with dimethyl sulfoxide

Purpose  

To compare the integration of osteochondral allografts cryopreserved at different temperatures and different concentrations of dimethyl sulfoxide in an in vivo sheep animal model.     

Repair of osteochondral lesions in the knee by chondrocyte implantation using the MACI? technique

Purpose  

Matrix-associated autologous chondrocyte implantation (MACI^?) is an innovative therapeutic option for the treatment of chondral and osteochondral lesions of the knee.     

Bony periosteum-covered iliac crest plug transplantation for severe osteochondral lesions of the talus: a modified mosaicplasty procedure

Purpose

This study reports first evidence of a modified procedure for osteochondral autologous transplantation where bony periosteum-covered plugs are harvested at the iliac crest and transplanted into the talar osteochondral lesion.

Methods

Thirteen out of 14 patients, average age 39.6 (SD 14.4) years, were followed clinically and radiographically for a median of 25 (24–28) months (minimal follow-up, 24 months).

Results

For these 13 patients, the American Orthopaedic Foot and Ankle Society hindfoot score increased from 47 (SD 11) points pre-operatively, to 81 (SD 14) points postoperatively (p < 0.0001). The average pain score decreased from 6.6 (SD 1.3) points pre-operatively, to 1.4 (SD 1.9) points postoperatively (p < 0.0001). Seven patients returned to sports activity. Radiographically good plug osteointegration was observed in nine out of 11 ankles. Follow-up arthroscopy showed fibrous cartilage in four ankles, periosteum hypertrophy in five ankles, and partial or total missing of coverage of the bone in three ankles. Three revision surgeries had to be performed.

Conclusions

This modified mosaicplasty might be recommended for severe and recurrent osteochondral lesions of the talus and may lead to restoration of the subchondral bone stock, formation of fibro-cartilage, and stable joint function.

Level of evidence

IV.     

Nutrition and degeneration of articular cartilage

Purpose

To determine the importance of synovial fluid (SF) or subchondral bone marrow (BM) as nutrition sources in cartilage degeneration.

Methods

Ninety-five-month-old male rabbits were randomly divided into 5 groups according to sources of nutrition: SFBM-both; BM-only; SF-only; None-SFBM; and Free plug (unrestricted). Nutrition to 4-mm-diameter cylindrical osteochondral plugs created on the trochlea of the distal femurs was obstructed by Polyvinyl Chloride (PVC) cap. Cartilage changes were assessed after 4, 8, and 12 weeks by histology, immunohistochemistry, and real-time PCR.

Results

Cartilage in the BM-only group suffered the greatest damage, followed by the None-SFBM and SF-only groups. Apoptosis was increased in the BM-only and None-SFBM groups compared with others. Cartilage was significantly thinner at all time points in the BM-only and None-SFBM groups when compared with SFBM-both and Free plug, whereas in the SF-only group, this difference occurred after 8 weeks. Compared with SFBM-both and Free plug, expression of collagen II and aggrecan mRNAs in all groups was decreased but MMP-3 increased, respectively.

Conclusion

Our data indicate that SF-derived nutrition is the dominant source of sustenance for adult cartilage structure and function. Cartilage damage is observed when the only nutrition source is the BM.     

Arthroscopic autologous chondrocyte implantation in osteochondral lesions of the talus: mid-term T2-mapping MRI evaluation

Purpose  

Autologous chondrocyte implantation (ACI) in the ankle has become an established procedure to treat osteochondral lesions. However, a non-invasive method able to provide information on the nature of the repair tissue is needed. Recently, MRI T2 mapping was identified as a method capable of qualitatively characterizing articular cartilage. The aim of this study was to evaluate the mid-term results of a series of patients arthroscopically treated by ACI and investigate the nature of the repair tissue by MRI T2 mapping.     

Osteochondral lesions of the humeral trochlea in the young athlete

Objective  The purpose of this study was to characterize the variety of osteochondral abnormalities of the humeral trochlea in the pediatric athlete. Materials and methods  Patients with trochlear abnormalities were identified through keyword search of radiology dictations from 1999 to 2007. The patient’s medical record, imaging studies, and surgical reports were reviewed. The osteochondral lesions were categorized based on the imaging appearance. Surgical results were reviewed in conjunction with the imaging findings. Results  Eighteen patients were identified. Trochlear lesions were stratified into two imaging groups: Osteochondral injury/osteochondritis dissecans (OCD) vs. avascular necrosis (AVN). The osteochondral injury group was stratified into medial and lateral trochlear abnormalities. The medial lesions (n = 3) were small (<6 mm) and were located on the posterior articular surface of the medial trochlea. The lateral lesions (n = 10) were larger (10–14 mm), circumscribed, and were located on the posterior inferior aspect of the lateral trochlea. Trochlear AVN (n = 5) affected development of the lateral trochlea (type A) or both the medial and lateral aspects of the trochlea (type B). AVN occurred exclusively in athletes with history of remote distal humeral fracture. Seven of the 18 patients underwent elbow arthroscopy. Surgical findings and treatment regimens are summarized. Conclusion  Trochlear lesions should be considered in throwing athletes presenting with medial elbow pain and flexion contracture/extension block. Medial trochlear osteochondral injuries may result from posteromedial olecranon abutment. Lateral OCD lesions occur in a characteristic vascular watershed zone resulting from the unique blood supply of the trochlea. Trochlear AVN may be unmasked years following treated distal humeral fracture when the athletic demands upon the adolescent elbow increase, revealing the altered growth and biomechanics.     

Splenic Artery Syndrome After Orthotopic Liver Transplantation: Treatment With the Amplatzer Vascular Plug

Purpose  

To evaluate the safety and efficacy of the Amplatzer vascular plug (AVP) for embolization of the splenic artery in patients with hepatic hypoperfusion after orthotopic liver transplantation (OLT).     

Computer-assisted mosaic arthroplasty using patient-specific instrument guides

Purpose  

Success of mosaic arthroplasty requires that the transplanted plugs be positioned to reconstruct the curvature and height of the original articular surface. This case report demonstrates how to achieve correct plug positioning using patient-specific instrument guides manufactured on a 3D printer.     

The treatment of chondral and osteochondral defects of the knee with autologous matrix-induced chondrogenesis (AMIC): method description and recent developments

Purpose  

Articular resurfacing by treatment of chondral defects may include chondral abrasion, autologous chondrocyte Implantation (ACI), matrix-induced chondrocyte transplantation (MACT) or osteochondral autologous transplantation (OATS). This technical note describes the method of autologous matrix-induced chondrogenesis (AMIC), a one-step procedure combining subchondral microfracture with the fixation of a collagen I/III membrane with fibrin glue or sutures.     

Embolization of pulmonary arteriovenous malformations using the Amplatzer vascular plug: successful treatment of 69 consecutive patients

Objective  

The technique of embolization of pulmonary arteriovenous malformations (PAVMs) with the Amplatzer vascular plug (AVP) has been reported, but no large series has evaluated the effectiveness of this relatively new embolic device. The purpose of this study is to assess the role of AVPs in the treatment of PAVMs.     

Arthroscopic microfracture for osteochondral lesions of the talus

The purpose of the present study was to evaluate the outcomes of arthroscopic microfracture for isolated osteochondral lesions of the talus without combined lesions, in patients of less than 50 years old with lesions of <1.5 cm². Thirty-five patients (35 ankles) with isolated osteochondral lesions of the talus were treated by arthroscopic microfracture. There were 27 men and 8 women of average age 35 years (range 17–50) and mean body mass index (BMI) 25 kg/m² (range 20–34) at the time of surgery. Clinical outcome evaluations were performed at a mean follow-up of 33 months. Overall results, as determined using American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot scores, were excellent in 16 (46%), good in 15 (43%), and fair in 4 (11%). Mean AOFAS scores improved from 63 points (range 52–77) preoperatively to 90 points (range 73–100) at final follow-up, median Ankle Activity Score (AAS) from 3 points (range 1–5) to 6 points (range 3–8), mean Visual Analogue Scale (VAS) scores from 7 points (range 5–8) to 2 points (range 0–5), and mean Short Form-36 scores showed improvements in physical function, role limitation, bodily pain, social function, and general health (P < 0.05). In terms of prognostic factors, a longer symptom duration was found to negatively affect outcome, as determined by AOFAS scores, AAS, and VAS scores. Arthroscopic microfracture for isolated osteochondral lesions of the talus is a safe and effective procedure, which provides good clinical outcomes in the majority of patients.     

Fibrin glue does not improve the fixation of press-fitted cell-free collagen gel plugs in an ex vivo cartilage repair model

Purpose  

Adequate graft fixation over a certain time period is necessary for successful cartilage repair and permanent integration of the graft into the surrounding tissue. The aim of the present study was to test the primary stability of a new cell-free collagen gel plug (CaReS^?-1S) with two different graft fixation techniques over a simulated early postoperative period.     

The effect of surface incongruity of grafted plugs in osteochondral grafting: a report of five cases

Although grafted osteochondral plugs should ideally have a smooth surface for mosaicplasty, surface incongruity is sometimes evident at the time of surgery. There may be no problem if there is depression of the grafted plugs, but graft protuberance may have an adverse effect. We studied five knees in five patients who had incongruity (protuberance or depression) of grafted osteochondral plugs at the time of mosaicplasty. The mean age at surgery was 36.6 years (range, 15–65 years), and the mean follow-up period was 32.9 months (range, 24–49 months). All patients underwent second-look arthroscopy after a mean post-surgical period of 14.8 months (range, 3–18 months). We divided the cases so that there were two in the protuberant group (P) and three in the depressed group (D). In P, all patients had a catching sensation about 4 months after surgery, and sometimes pain in the knee joint. Second-look arthroscopy revealed fissuring of the plugs and fibrillation around the recipient site. In D, there were no symptoms due to the depressed plugs. Second-look arthroscopy showed that the depressed areas were covered with fibrocartilage-like tissue, and that the joint surface was smooth. In conclusion, our clinical results and second-look arthroscopic evaluation suggest that isolated osteochondral plug depressions of not greater than 1 mm could still promote acceptable cartilage healing leading to good clinical outcomes. However, plug protuberance at mosaicplasty should always be avoided.