A New Total Knee Arthroplasty Technique for Valgus Knees that preserves the deep layer of the medial collateral ligament.

OBJECTIVE: The aim of this study was to assess the outcomes and complications, such as tibiofemoral instability and recurrence of valgus deformity, of total knee arthroplasty for valgus knees with a new technique preserving the deep layer of the medial collateral ligament. METHODS: In this study 33 (4 male and 29 female) patients, and a total of 36 (26 knees with osteoarthritis and 10 with rheumatoid arthritis) knees with a standing femorotibial angle (FTA) of <170° were included. Posterior Stabilized (PS) implants were used in 34 knees, rotating hinged knee implants were used in 2 knees. The procedures were carried out by a single surgeon protecting the deep layer of the medial collateral ligament. The patients' average age at the time of the operation was 67.6 ± 12 years, and the average follow-up period was 9.0 ± 3 years (range, 4-15 years). The Japanese Orthopaedic Association (JOA) knee score, range of motion (ROM) (extension/flexion; measured in degrees), FTA (measured in degrees) and complications were investigated. RESULTS: The Japanese Orthopaedic Association knee score significantly improved from an average of 51 ± 12 points before the operation to 86 ± 9 points after the operation (P <0.001). The extension ROM and flexion ROM improved from, -13 ± 13° to a postoperative average of -2 ± 4°, and 115 ± 25° to a postoperative average of 125 ± 18° respectively (P <0.001). The standing FTA significantly improved from 158 ± 9° to an average of 173 ± 2° after the operation (P <0.001). Thirty-four knees with severe valgus deformity were operated on using pos- terior stabilised implants, while only two knees required constrained implants. During follow-up, no complications, such as tibiofemoral instability, recurrence of valgus deformity, patellar necrosis, deep infection, wound problems, or peroneal nerve paralysis were observed. CONCLUSION: This study has shown us that after performing TKA while preserving the d-MCL for valgus knee deformity good clinical results were obtained and no complications were observed. LEVEL OF EVIDENCE: Level IV, Therapeutic Study.

Mutation screening of the muscarinic m2 and m3 receptor genes in asthmatics, outgrow subjects, and normal controls.

Muscarinic receptors are important in the development of airway hyperresponsiveness. In some patients with asthma and in animal models of hyperreactivity, functional abnormalities in these receptors are suggested to contribute to disease. Here, we have screened for single nucleotide polymorphisms in the coding region of human muscarinic m2 and m3 receptor genes using direct fluorescence sequencing. DNA samples from 102 current asthmatics and 58 who had outgrown asthma ("outgrow" patients) were compared with 70 random non-asthmatic controls. A mutation characterized by a single base substitution (A1050G, Ser350Ser) was identified in the muscarinic m2 receptor gene. This polymorphism was common and was represented in all three groups studied. In contrast, in the m3 receptor coding region examined, we found a very rare nucleotide variant (C261T, Ile87Ile), identified in only one of the 230 samples genotyped. Therefore, neither A1050G in the m2 receptor nor C261T in the m3 receptor is likely to be functionally significant for airway hyperresponsiveness in asthma. Our data suggest that both the m2 and m3 receptor genes are highly conserved, and no significant genetic mutations are related to their possible functional changes in human asthma.