Arturo Makino

Osteonecrosis of the knee following arthroscopic meniscectomy in patients over 50-years old

We reviewed eight patients over 50-years old, with an initial diagnosis of medial meniscal tear confirmed with magnetic resonance imaging (MRI) and with no evidence of osteonecrosis. After arthroscopic meniscectomy, all patients had recurrent aggravated knee pain and reevaluation with MRI showed images compatible with osteonecrosis. The average age was 65 years (range 54 to 75 years). The mean time from MRI to surgery was 8 weeks (range 1 to 28 weeks). In five patients a total meniscectomy, and in three a partial meniscectomy with recontouring of the meniscus were performed. Surgical treatment was initially successful, but all eight patients returned to our office with recurrent aggravated pain in the treated knee. Reevaluation with MRI, at an average of 18 weeks postoperatively, found abnormalities at the medial condyle consistent with osteonecrosis. The purpose of this study is to report a potentially serious outcome after arthroscopic meniscectomy in patients over 50-years old.

Arthroscopic Fixation of Osteochondritis Dissecans of the Knee Clinical, Magnetic Resonance Imaging, and Arthroscopic Follow-up

Background Optimal treatment of osteochondritis dissecans of the knee is still controversial. Purpose To review a group of patients with osteochondritis dissecans of the knee who were treated with arthroscopic compressive screw fixation and who were evaluated with magnetic resonance imaging studies and a second-look arthroscopic procedure at follow-up. Study Design Case series; level of evidence, 4. Methods A total of 14 patients (15 knees) with osteochondritis dissecans of the knee were treated with arthroscopic titanium Herbert screw fixation of the osteochondral fragment. A second-look arthroscopic procedure was performed to remove hardware and to evaluate fragment stability. At final follow-up, magnetic resonance imaging studies were used to evaluate potential healing of the subchondral bone. Outcomes were clinically evaluated at a mean follow-up of 50 months (range, 25-104 months) by the Lysholm score and by the International Knee Documentation Committee score. Results At second-look arthroscopy, 14 of 15 knees showed evidence of a stable fragment with an intact smooth surface. According to magnetic resonance imaging parameters, 14 knees showed evidence of a healing process of the osteochondral fragment. The average Lysholm score improved 18 points from a mean of 79 preoperatively to 97 postoperatively, and according to the International Knee Documentation Committee score, 13 of 15 knees showed a normal result. Conclusion This study suggests that magnetic resonance imaging parameters of a healed osteochondral fragment and patients with satisfactory functional results correspond with arthroscopic evidence of fragment stability. According to this study, arthroscopic fixation with compressive screws is an effective method of repair for osteochondritis dissecans of the knee.

Treatment of Chronic Patellar Tendinopathy with Autologous Bone Marrow Stem Cells: A 5-Year-Followup

The purpose of this study is to determine if patients with chronic patellar tendinopathy will improve clinically after the inoculation of bone marrow mononuclear cells (BM-MNCs). Eight patients with chronic patellar tendinopathy were included. Patients averaged 24 years old (range 14–35). All patients were refractory to conservative treatment for at least 6 months before the procedure. BM-MNCs were harvested from the iliac bone crest and inoculated under ultrasound guide in the patellar tendon lesion. Improvement was assessed through established clinical scores and ultrasound. At 5-year followup, statistically significant improvement was seen for most clinical scores. Seven of eight patients said they would have the procedure again if they had the same problem in the opposite knee and were completely satisfied with the procedure. Seven of 8 patients thought that the results of the procedure were excellent. According to our results, inoculation of BM-MNCs could be considered as a potential therapy for those patients with chronic patellar tendinopathy refractory to nonoperative treatments.

Tumors About the Knee Misdiagnosed as Athletic Injuries

Background: Musculoskeletal tumors may originally mimic a traumatic condition, and, on the basis of an erroneous diagnosis of an athletic injury, an invasive diagnostic or therapeutic procedure may be performed. We determined the number of such cases treated at our institution, and we analyzed the initial and final diagnoses as well as the changes in the indicated oncologic surgical technique due to the initial erroneous diagnosis. Methods: Twenty-five patients who had a bone or soft-tissue tumor about the knee that originally had been diagnosed as an athletic injury were referred to our institution. The complete clinical, radiographic, and pathological records were reviewed. Studies that had been performed prior to the invasive procedure and at the time of admission to our institution were evaluated to determine differences in the tumor stage and the oncologic treatment that was indicated at each time. Results: Of 667 knee tumors diagnosed in our institution, twenty-five (3.7%) previously had been treated with an intra-articular procedure as a result of a misdiagnosis of an athletic injury. The final diagnoses made at our institution were a benign tumor in eleven patients and a malignant tumor in fourteen. Oncologic surgical treatment was affected in fifteen of the twenty-five patients. Conclusions: When a knee tumor is initially misdiagnosed as an athletic injury, treatment may be adversely affected by the delay in diagnosis or an inappropriate invasive procedure that results in extension of the tumor. Initial poor-quality radiographs and an unquestioned original diagnosis despite persistent symptoms were the most frequent causes of an erroneous diagnosis. Level of Evidence: Prognostic study, Level IV (case series). See Instructions to Authors for a complete description of levels of evidence.

Localized pigmented villonodular synovitis of the posterior compartment of the knee: Diagnosis with magnetic resonance imaging

Localized Pigmented Villonodular Synovitis (LPVS) is a lesion that may affect any joint but is frequently found in the knee. Detection and diagnosis of this entity are clinically difficult, and plain roentgenograms are usually within normal limits. We present a case report of a LPVS localized at the posterior compartment of the knee that mimics a meniscal lesion. Magnetic resonance imaging (MRI) performed before the resection through an arthroscopic procedure helped to diagnose the tumor, which in this case had an infrequent location. MRI is a valuable clinical tool for the assessment of intraarticular tumors of the knee joint that otherwise may be misdiagnosed and treated as a meniscal tear.

Simultaneous rupture of the anterior cruciate ligament and a knee tumor

We report two patients with simultaneous lesions about the knee; a traumatic injury (acute anterior cruciate ligament rupture) and a musculoskeletal tumour; that may be particularly misleading for the treating surgeon.