ABSTRACT: High tibial osteotomy (HTO) is a method used to treat medial compartmental osteoarthritis in the knee. The realignment of the knee changes the loading patterns within the joint and may allow for regeneration of articular cartilage. Magnetic resonance imaging methods can be used to assess the quality of the regenerated cartilage.
Altering mechanical alignment through HTO will have predictable effects on articular cartilage, allowing cartilage preservation and possible regeneration. Quality of regenerated cartilage will be inferior to normal articular cartilage.
Case series; Level of evidence, 4.
Ten patients undergoing medial opening wedge HTO were evaluated using dGEMRIC methods (ie, delayed gadolinium-enhanced magnetic resonance imaging of cartilage) preoperatively and at 6 months, 1 year, and 2 years after HTO. Magnetic resonance images were evaluated by hand segmentation, and T1(Gd) relaxation times reflective of glycosaminoglycan content were determined for these regions of interest using magnetic resonance imaging analysis software.
The lateral compartment displayed higher T1(Gd) values than the medial compartment at baseline. Initially, a decrease in T1(Gd) values on the medial side were observed for all patients at 6 months and remained reduced for all but 2 participants at 1 year and 2 years after HTO. However, on the medial side after 6 months, the rate of change for T1(Gd) values shifted from being negative (-9.6 milliseconds per month) to being positive (1.7 milliseconds per month). A positive change in the T1(Gd) of the medial tibial plateau was responsible for the positive overall change in the medial compartment. There was no significant difference in the rate of change on the lateral side (P = .141), with the average over the 2-year period being a decrease of 2.28 milliseconds per month.
Medial opening wedge HTO provides subjective improvements in pain and quality of life, but the potential benefit of allowing articular cartilage preservation and possible regeneration is not well established. Results showed that after a nonweightbearing period, the rate of change in the medial compartment changes from negative to positive, indicating the potential for articular cartilage recovery secondary to an improved mechanical environment.
The American journal of sports medicine 02/2011; 39(5):1039-45. · 3.61 Impact Factor
ABSTRACT: To describe the associations between physical disability measures and knee cartilage defects in obese adults.
One hundred and eleven obese subjects were recruited from laparoscopic adjustable gastric banding or exercise/diet weight loss programmes. All subjects completed disease-specific (WOMAC) and general health status (SF-36) questionnaires, and were assessed for range of knee motion, tibiofemoral alignment and quadriceps strength. Knee cartilage defects were graded on MRI according to established protocol. Regression analysis was adjusted for age, gender, BMI and presence of clinical knee OA.
The association between higher whole compartment cartilage defect scores and increasing BMI, age and clinical knee OA was confirmed in this obese cohort (r = 0.27, P = 0.01; r = 0.26, P = 0.007; P < 0.0001, respectively), whereas new associations were found with reduced knee range of motion (r = 0.5, P < 0.0001). No associations were found between defect scores and quadriceps strength. Varus malalignment was associated with higher medial cartilage defect scores (r = 0.33, P = 0.013). Higher levels of pain, stiffness and physical disability (WOMAC, SF-36) were associated with higher medial compartment and patella cartilage defect scores.
Knee cartilage defects increase with increasing obesity and are associated with both objective and self-reported measures of physical disability. Longitudinal studies are required to assess the potential for change or improvement in cartilage defects with weight loss.
Rheumatology (Oxford, England) 08/2009; 48(10):1290-3. · 4.24 Impact Factor
ABSTRACT: The purpose of our study was to evaluate the impact of preoperative magnetic resonance imaging (MRI) assessment of articular knee pathology on the clinical management of patients presenting with joint line pain.
A preliminary study on 100 patients was performed to assess the accuracy of specific MRI sequences, using arthroscopy as a gold standard. Six hundred and eighteen consecutive patients with knee symptoms presenting to 2 specialist knee surgeons were then recruited. A clinical diagnosis of an arthroscopically treatable lesion was made in all cases. Clinical assessment data were correlated to subsequent MRI findings, recording any discrepancy and in particular whether or not MRI findings influenced management decisions.
In the preliminary study, MRI sequences had an overall sensitivity of 83.2% and a specificity of 94.3% for the detection of chondral lesions. However, when considering arthroscopic grade III and IV lesions, MRI sensitivity and specificity were improved to 84.5% and 97.1%. In the second phase of the study, 141 (22.8%) of the 618 patients presenting with knee symptoms had an altered clinical management subsequent to MRI. The presence of unexpected chondral lesions was found in 77 of these patients. Conversely, 22 patients with clinical symptoms suspicious for simple chondral degeneration had unstable meniscal tears.
We suggest that preoperative MRI scanning identifies a group of patients who have more advanced degenerative joint disease than the clinical assessment and the plain radiographs suggest. This would expedite definitive surgery in patients with advanced osteoarthritis on MRI scans.
Level II, development of diagnostic criteria on basis of consecutive patients with universally applied gold standard.
Arthroscopy The Journal of Arthroscopic and Related Surgery 06/2009; 25(5):473-80. · 3.02 Impact Factor
The Journal of Bone and Joint Surgery 01/2006; 87(12):2763-7. · 3.27 Impact Factor