Prospective Long-term Follow-up of Autologous Chondrocyte Implantation With Periosteum Versus Matrix-Associated Autologous Chondrocyte Implantation: A Randomized Clinical Trial

Background: Matrix-associated autologous chondrocyte implantation (MACI) is a further development of the original autologous chondrocyte implantation periosteal flap technique (ACI-P) for the treatment of articular cartilage defects. Purpose: We aimed to establish whether MACI or ACI-P provides superior long-term outcomes in terms of patient satisfaction, clinical assessment, and magnetic resonance imaging (MRI) evaluation. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: A total of 21 patients with cartilage defects at the femoral condyle were randomized to MACI (n = 11) or ACI-P (n = 10) between the years 2004 and 2006. Patients were assessed for subjective International Knee Documentation Committee (IKDC) score, Lysholm and Gillquist score, Tegner Activity Score, and 36-Item Short Form Health Survey (SF-36) preoperatively (T0), at 1 and 2 years postoperatively (T1, T2), and at the final follow-up 8 to 11 years after surgery (T3). Onset of osteoarthritis was determined using the Kellgren-Lawrence score and Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score, and delayed gadolinium-enhanced MRI of cartilage was used to evaluate the cartilage. Adverse events were recorded to assess safety. Results: There were 16 patients (MACI, n = 9; ACI-P, n = 7) who were reassessed on average 9.6 years after surgery (76% followup rate). The Lysholm and Gillquist score improved in both groups after surgery and remained elevated but reached statistical significance only in ACI-P at T1 and T2. IKDC scores increased significantly at all postoperative evaluation time points in ACIP. In MACI, IKDC scores showed a significant increase at T1 and T3 when compared with T0. In the majority of the patients (10/16; MACI, 5/9; ACI-P, 5/7) a complete defect filling was present at the final follow-up as shown by the MOCART score, and 1 patient in the ACI-P group displayed hypertrophy of the repair tissue, which represents 6% of the whole study group and 14.3% of the ACI-P group. Besides higher SF-36 vitality scores in ACI-P at T3, no significant differences were seen in clinical scores and MRI scores between the 2 methods at any time point. Revision rate was 33.3% in MACI and 28.6% in ACI-P at the last follow-up. Conclusion: Our long-term results suggest that first- and third-generation ACI methods are equally effective treatments for isolated full-thickness cartilage defects of the knee. With the number of participants available, no significant difference was noted between MACI and ACI-P at any time point. Interpretation of our data has to be performed with caution due to the small sample size, which was further limited by a loss to follow-up of 24%

CT-guided radiofrequency ablation of osteoid osteoma: correlation of clinical outcome and imaging features

PURPOSEWe aimed to retrospectively evaluate the computed tomography (CT) and magnetic resonance imaging (MRI) findings of patients with osteoid osteoma treated with CT-guided radiofrequency ablation (RFA) along with the clinical outcome and long-term success.MATERIALS AND METHODSSeventy-three CT-guided RFA procedures were performed in 72 patients. The long-term success was assessed using a questionnaire including several visual analog scale scores. The CT evaluation included pre- and immediate postprocedural imaging of all 72 patients, and MRI was performed in 18 patients with follow-up imaging (mean, 3.4±2.2 months). The evaluation criteria included nidus morphology and a correlation with markers of clinical success.RESULTSThe primary technique effectiveness rate was 71/72 (99%). One relapse was successfully retreated, leading to a secondary technique effectiveness rate of 72/72 (100%). The long-term follow-up (mean, 51.2±31.2 months; range, 3–109 months) revealed a highly significant reduction of all assessed limitation scores (P < 0.001). The CT morphology was typical in all cases and did not change during the short-term follow-up. The follow-up MRI patterns varied considerably, including persistent nidus contrast enhancement in one-third (6/18) and persistent marrow edema in half (9/18) of the patients. None of the investigated MRI and CT patterns correlated with the clinical outcome.CONCLUSIONThe long-term outcome of CT-guided RFA of osteoid osteoma is excellent. There is no correlation of the CT and MRI patterns with the clinical outcome. Thus, the treatment decisions should not be solely based on the imaging findings. Investigators should also be aware of the variety of imaging patterns after RFA

Imaging of hip and thigh muscle injury: a pictorial review

Abstract Muscle injuries of the hip and thigh are a highly relevant issue in competitive sports imaging. The gold standard in diagnostic imaging of muscle injuries is magnetic resonance imaging (MRI). Radiologists need to be familiar with typical MRI findings in order to accurately detect and classify muscle injuries. Proper interpretation of the findings is crucial, especially in elite athletes. In soccer players, muscle injuries of the hip and thigh are the most common reason for missing a game. The present pictorial review deals with the diagnostic assessment, especially MRI, of muscle injuries of the hip and thigh. Typical MR findings in muscle injuries include edema, hematoma, and tendinous avulsion as well as partial or complete muscle tear. To estimate the time to return to play, a grading into three groups—muscle strain, partial tear, complete tear—has traditionally been used. Taking into account the most recent literature, there are other prognostic factors such as the longitudinal length of a tear, the tendon’s intramuscular component, or persisting edema

Fixation of Unstable Femoral Juvenile Osteochondritis Dissecans Lesions with Bioabsorbable Pins—Clinical and Radiographic Outcomes

Juvenile Osteochondritis Dissecans (JOCD) is a common reason for knee pain among children. The aim of this case study was to report on clinical and radiographic outcomes after fixation of an osteochondral fragment with bioabsorbable pins in children with open growth plates. We hypothesized that surgical treatment with this technique will result in good function, high rates of radiographic healing and high return to sport rates. A total of 13 knees in 12 patients (6 male, 6 female) with a median of 13 years (11, 17) were evaluated retrospectively at a minimum clinical follow-up of 24 months. Inclusion criteria were defined as open growth plates and an unstable osteochondral lesion grade III or IV. The clinical outcome was evaluated utilizing three standardized patient-reported outcome scores (Tegner Activity Scale [TAS], Knee Injury and Osteoarthritis Outcome Score [KOOS], Lysholm Score). All patients underwent magnetic resonance imaging 15 months (3, 34) after surgical treatment and defect healing was evaluated utilizing a modified version of the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Due to the small sample size, the data was reported descriptively. The interobserver variability was calculated with the Spearman rank correlation coefficient. Comparisons were made with Wilcoxon sign rank test (or sign test). At final follow-up the median KOOS Score was 98% (79.2%, 100%) and the median Lysholm Score was 94 (69, 100) points. The Tegner Activity Scale was 7 (4, 10) points preoperatively and 7 (4,10) points postoperatively (p = 0.5). Complete bony ingrowth occurred in 9 knees (69%), complete cartilage defect repair in 10 knees (77%) and integration to the border zone was found in 11 knees (85%) 15 (3, 34) months following surgical treatment. Fixation of osteochondral fragments with bioabsorbable pins resulted in good functional and radiographic outcomes, a high return to sport- and a low complication rate among children with open growth plates

MRI patterns indicate treatment success and tumor relapse following radiofrequency ablation of osteoblastoma

Purpose To explore the typical magnetic resonance imaging (MRI) pattern of osteoblastoma (OB) after radiofrequency ablation (RFA) treatment and to identify signs indicating treatment success or relapse. Materials and methods Forty-four follow-up MRI examinations of 15 patients with OB who had undergone 19 RFA procedures were analyzed retrospectively. An early follow-up group (1–4 months after RFA) and a late follow-up group (8–131 months after RFA) were established. The groups were further subdivided according to treatment success. Images were analyzed for the presence of central nidus enhancement (CNE), peripheral nidus enhancement (PNE), perifocal bone marrow edema (PBME) and fatty nidus conversion (FNC). Results The early follow-up MRI image from every patient in the treatment success group exhibited a target-like appearance with negative CNE and positive PNE or PBME. PNE and PBME were observed in 93% and 71% of the early follow-up images, respectively. A target-like appearance was observed in 25% of the late follow-up images, and PNE and PBME were each observed in 20% of these images. FNC was not observed in the early follow-up images, but was seen in 55% of the late follow-up images. All three MRI images of the patients exhibiting clinical recurrence demonstrated strong CNE, PNE and extensive PMBE, which was in contrast to the images of the patients exhibiting treatment success. Conclusion A target-like appearance of OB in early follow-up MRI examination indicates treatment success. PNE and PBME typically reduce over time and can lead to FNC in successfully treated patients. CNE recurrence, PNE and extensive PBME are signs of relapse

CT-Guided Biopsy in Suspected Spondylodiscitis--The Association of Paravertebral Inflammation with Microbial Pathogen Detection.

To search for imaging characteristics distinguishing patients with successful from those with futile microbiological pathogen detection by CT-guided biopsy in suspected spondylodiscitis.34 consecutive patients with suspected spondylodiscitis underwent CT-guided biopsy for pathogen detection. MR-images were assessed for inflammatory infiltration of disks, adjacent vertebrae, epidural and paravertebral space. CT-images were reviewed for arrosion of adjacent end plates and reduced disk height. Biopsy samples were sent for microbiological examination in 34/34 patients, and for additional histological analysis in 28/34 patients.Paravertebral infiltration was present in all 10/10 patients with positive microbiology and occurred in only 12/24 patients with negative microbiology, resulting in a sensitivity of 100% and a specificity of 50% for pathogen detection. Despite its limited sensitivities, epidural infiltration and paravertebral abscesses showed considerably higher specificities of 83.3% and 90.9%, respectively. Paravertebral infiltration was more extensive in patients with positive as compared to negative microbiology (p = 0.002). Even though sensitivities for pathogen detection were also high in case of vertebral and disk infiltration, or end plate arrosion, specificities remained below 10%.Inflammatory infiltration of the paravertebral space indicated successful pathogen detection by CT-guided biopsy. Specificity was increased by the additional occurrence of epidural infiltration or paravertebral abscesses

63 year-old male patient with suspected spondylodiscitis.

<p>Sagittal T1-weighted fat-saturated contrast-enhanced sequence <b>(A)</b> demonstrates florid enhancement of adjacent vertebral bodies and paravertebral soft tissue. Note concomitant T2-hyperintensity of the disk space as well as vertebral and paravertebral edema on sagittal STIR image <b>(B)</b>. Sagittal CT reconstructions reveal arrosion of adjoining end-plates <b>(C)</b>. Paravertebral soft tissue enhancement is even more conspicuous on contrast-enhanced axial T1-weighted fat-saturated sequence <b>(D)</b>. An abscess is identified in the left psoas muscle as T2-hyperintensity surrounded by a T2-hypointense rim <b>(E)</b>. CT-guided biopsy of the psoas abscess disclosed methicillin-resistant staphylococcus aureus infection <b>(F)</b>.</p

53 year-old female patient with suspected spondylodiscitis.

<p>Sagittal T1-weighted fat-saturated contrast-enhanced sequence <b>(A)</b> again illustrates prominent enhancement of adjacent vertebral bodies but not of paravertebral soft tissue. T2-hyperintensity of the disk space and vertebral edema is documented on sagittal STIR image <b>(B)</b>. Sagittal CT reconstructions illustrate arrosion of the bottom end-plate L4 <b>(C)</b>. No significant paravertebral soft tissue infiltration is appreciated on contrast-enhanced axial T1-weighted fat-saturated <b>(D)</b> or axial T2-weighted <b>(E)</b> sequences. 2.2 cm CT-guided core biopsies of the intervertebral space from the documented position failed to provide a causative microbiological pathogen <b>(F)</b>.</p