Successful treatment of painful irreparable partial meniscal defects with a polyurethane scaffold: two-year safety and clinical outcomes.

BACKGROUND: A novel, biodegradable, polyurethane scaffold was designed to fulfill an unmet clinical need in the treatment of patients with painful irreparable partial meniscal defects. HYPOTHESIS: The use of an acellular polyurethane scaffold for new tissue generation in irreparable partial meniscal defects provides both pain relief and improved functionality. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Fifty-two patients with irreparable partial meniscal defects (34 medial and 18 lateral, 88% with 1-3 previous surgeries on the index meniscus) were implanted with a polyurethane scaffold in a prospective, single-arm, multicenter, proof-of-principle study. Safety was assessed by the rate of scaffold-related serious adverse events (SAEs) and the International Cartilage Repair Society articular cartilage scoring system comparing magnetic resonance imaging (MRI) at 24 months to MRI at baseline (1 week). Kaplan-Meier time to treatment failure distributions were performed. Clinical outcomes were measured comparing visual analog scale, International Knee Documentation Committee, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Lysholm scores at 24 months from baseline (entry into study). RESULTS: Clinically and statistically significant improvements (P < .0001) compared with baseline were reported in all clinical outcome scores (baseline/24 months): visual analog scale (45.7/20.3), International Knee Documentation Committee (45.4/70.1), KOOS symptoms (64.6/78.3), KOOS pain (57.5/78.6), KOOS activities of daily living (68.8/84.2), KOOS sports (30.5/59.0), KOOS quality of life (33.9/56.6), and Lysholm (60.1/80.7), demonstrating improvements in both pain and function. The incidence of treatment failure was 9 (17.3%) patients, of which 3 patients (8.8%) had medial meniscal defects and 6 patients (33.3%) had lateral meniscal defects. There were 9 SAEs requiring reoperation. Stable or improved International Cartilage Repair Society cartilage grades were observed in 92.5% of patients between baseline and 24 months. CONCLUSION: At 2 years after implantation, safety and clinical outcome data from this study support the use of the polyurethane scaffold for the treatment of irreparable, painful, partial meniscal defects.

A new symptomatic intra-articular cord-like structure associated with discoid meniscus.

We introduce a new, not yet described cord-like structure of the knee of children associated with discoid or enlarged menisci. This structure was responsible for knee pathology (loss of extension) in 3 cases. The patients (5 to 8 years of age) complained of knee pain without skeletal abnormality or trauma. Magnetic resonance imaging revealed enlarged or discoid lateral menisci. The patients showed increasing limp with limited range of motion. Lack of extension was between 10 degrees and 45 degrees and continued under anesthesia. During arthroscopy, the menisci and the anterior and posterior cruciate ligaments (ACL, PCL) showed no abnormality other than the variant of the lateral meniscus described above. A tight cord-like structure was imposed, running laterally along the ACL. This cord-like structure was attached to the lateral femoral intercondylar area and the posterior horn region of the lateral meniscus in a sail-like shape. Two knees showed abnormal mobility of the lateral meniscus, tending to luxate. The ligamentous structure was cut stepwise lateral to the ACL, leaving the entire lateral meniscus undisturbed. Finally, full extension was achieved. Examination 7 to 27 months after surgery showed asymptomatic knees. This ligamentous structure is an important differential diagnosis to symptoms usually referred to as meniscus pathology. The appropriate treatment involves dissection. A loss of meniscal tissue followed by development of osteoarthritis can be prevented.

Arthroscopical removal of a projectile from the intra-articular cavity of the knee joint.

We report the case of a 29-year-old patient with an uncommon handgun accident. A gun was resting in his pocket when an accidental shot was fired. The projectile penetrated the skin of the thigh, travelled through the quadriceps muscle and entered the articular cavity at the upper pole of the suprapatellar recess. It passed the femoropatellar joint space and stopped within the infra-articular fad pad. The bullet was localized by conventional X-rays and removed by arthroscopy. The patient developed no infection, and in a clinical follow-up examination 6 months postoperatively, we observed no pathological findings.

Arthroscopic all-inside meniscus repair using a new refixation device: a prospective study.

PURPOSE: To evaluate complications and clinical results after meniscus refixation using a new all-inside technique. TYPE OF STUDY: Prospective clinical study. METHODS: This study reports clinical results of 37 patients after refixation of an unstable bucket-handle meniscus tear using a new all-inside technique (Mitek Meniscal Repair System; Mitek, Ethicon, Norderstedt, Germany). Twenty tears were located in the peripheral third (red zone) and 17 in the middle third (red/white zone). The average operating time of meniscus refixation was 29.4 minutes. In 17 patients, a reconstruction of the anterior cruciate ligament (ACL) was performed 6 to 8 weeks after the refixation. All patients (aged 15 to 48 years) were re-examined after a minimum follow-up of 12 months. RESULTS: In the ACL group (n = 17) we examined the menisci arthroscopically at surgery. All menisci were still in the reduced position and they were stable to probing. In 12 cases, the anchors were not visible at arthroscopy; in 7 cases, the vertical bar was lying just beyond the femoral meniscus surface. In 1 case, we observed superficial damage of the femoral cartilage in the corresponding area. One patient developed superficial posteromedial knee pain after 4 weeks due migration of a staple into the subcutaneous fat tissue. There were 5 reruptures during the first postoperative year. Two patients reported an adequate trauma, but all had tears in the middle one third of the meniscus (red/white zone). At the 1-year follow-up, none of the remaining 32 patients had clinical symptoms indicating a rerupture such as blocking, medial joint pain, or positive meniscus signs. No patient had an effusion or local swelling. The average pretraumatic Lysholm score decreased from 95 to 91 points. The Tegner activity score decreased from 4.9 (pretrauma) to 3.6 (postoperatively). CONCLUSIONS: Short-term clinical results using an all-inside meniscus repair system seem to be promising. However, a longer follow-up is needed.