Origin of the direct and reflected head of the rectus femoris: an anatomic study.

PURPOSE: This study aimed to define the footprint of the direct and reflected heads of the rectus femoris and the relation of the anterior inferior iliac spine (AIIS) to adjacent neurovascular (lateral circumflex femoral artery and femoral nerve), bony (anterior superior iliac spine [ASIS]), and tendinous structures (iliopsoas). METHODS: Twelve fresh-frozen cadaveric hip joints from 6 cadavers, average age of 44.5 (±9.9) years, were carefully dissected of skin and fascia to expose the muscular, capsular, and bony structures of the anterior hip and pelvis. Using digital calipers, measurements were taken of the footprint of the rectus femoris on the AIIS, superior-lateral acetabulum and hip capsule, and adjacent anatomic structures. RESULTS: The average dimensions of the footprint of the direct head of the rectus femoris were 13.4 mm (±1.7) × 26.0 mm (±4.1), whereas the dimensions of the reflected head footprint were 47.7 mm (±4.4) × 16.8 mm (±2.2). Important anatomic structures, including the femoral nerve, psoas tendon, and lateral circumflex femoral artery, were noted in proximity to the AIIS. The neurovascular structure closest to the AIIS was the femoral nerve (20.8 ± 3.4 mm). CONCLUSIONS: The rectus femoris direct and reflected heads originate over a broad area of the anterolateral pelvis and are in close proximity to critical neurovascular structures, and care must be taken to avoid them during hip arthroscopy. CLINICAL RELEVANCE: A thorough knowledge of the anatomy of the proximal rectus femoris is valuable for any surgical exposure of the anterior hip joint, particularly arthroscopic subspine decompression and open femoroacetabular impingement (FAI) surgery.

A Radiographic Sizing Algorithm for Tibial Plateau Osteochondral Allografts.

OBJECTIVE: Tibial plateau osteochondral allograft transplantation is a promising treatment for symptomatic chondral damage of the proximal tibia due to a variety of etiologies. The purpose of this investigation is to develop an accurate and reproducible algorithm for sizing tibial plateau allografts based on recipient radiographs. DESIGN: A cadaveric study was performed in which radiographs of 10 fresh frozen cadaveric knees were compared to measured digital photographs of the disarticulated specimens. By comparing the average distance between standard anatomical landmarks on the radiographs to the gross specimens, a correlation factor was calculated that could be applied to recipient radiograph measurements for more accurate sizing of tibial plateau allografts. RESULTS: In the coronal plane there were no differences between the mean radiographic and mean morphologic measurements of either the medial or lateral tibial plateau. However, in the sagittal plane the anatomic specimens of the medial and lateral plateau were 90% and 80%, respectively, of the measurements made from the lateral radiograph. CONCLUSIONS: This cadaveric investigation is the first to propose a sizing algorithm for tibial plateau osteochondral allografts. Based on the results, an anteroposterior radiograph can reliably measure the width of both the medial and lateral tibial plateau without any correction needed. The average morphological lengths of the medial and lateral tibial plateau, on the other hand, were found to be 90% and 80%, respectively, of the radiographically measured lengths. Without correction, this would lead to the implantation of oversized grafts that may contribute to early failure.

Interrater and Intrarater Reliability of Arthroscopic Measurements of Articular Cartilage Defects in the Knee.

BACKGROUND: Cartilage lesions of the knee are difficult to treat. Lesion size is a critical factor in treatment algorithms, and the accurate, reproducible sizing of lesions is important. In this study, we evaluated the interrater and intrarater reliability of, and correlations in relation to, various arthroscopic sizing techniques. METHODS: Five lesions were created in each of 10 cadaveric knees (International Cartilage Repair Society grade 3C). Three orthopaedic surgeons used 4 techniques (visualization and use of a 3-mm probe, a simple metal ruler, and a sliding metallic ruler tool) to estimate lesion size. Repeated-measures data were analyzed using a mixed-effect linear model. The differences between observed and gold-standard (plastic mold) values were used as the response. Intraclass and interclass correlation coefficient (ICC) values for intrarater and interrater reliability were computed, as were overall correlation coefficients between measurements and gold standards. RESULTS: The mean lesion size was 2.37 cm (range, 0.36 to 6.02 cm). Rater, lesion location and size, and measurement method all affected the cartilage defect measurements. Surgeons underestimated lesion size, and measurements of larger lesions had a higher percentage of error compared with those of smaller lesions. When compared with plastic molds of lesions, 60.5% of surgeon measurements underestimated lesion size. Overall, the correlation between measurements and gold standards was strongest for the simple metal ruler method and weakest for the visualization method. CONCLUSIONS: Several factors may influence arthroscopic estimation of cartilage lesion size: the lesion location, measurement tool, surgeon, and defect size itself. The intrarater and interrater reliability was moderate to good using a 3-mm probe, sliding metallic ruler tool, or simple metal ruler and was fair to moderate using visualization only. CLINICAL RELEVANCE: There is a need for more accurate methods of determining the size of articular cartilage lesions.

Meniscal Allograft Transplantation: State of the Art.

Meniscal allograft transplantation has evolved over the years to provide a state-of-the-art technique for the sports medicine surgeon to utilize in preserving contact mechanics and function of the knee in irreparable meniscal pathology. However, this procedure continues to spark considerable debate on proper tissue processing techniques, acceptable indications, methods of implantation, and potential long-term outcomes.

The Prevalence of Meniscal Pathology in Asymptomatic Athletes.

BACKGROUND: Meniscal pathology is a commonly seen orthopedic condition that can affect a wide age range of patients. Athletes subject their menisci to an increased amount of stress during their careers and may increase their risk of meniscal pathology. OBJECTIVE: The purpose of this systematic review is to evaluate the prevalence of isolated meniscal pathology in asymptomatic athletes. METHODS: A systematic review was undertaken to determine the prevalence of meniscal pathology in asymptomatic athletes. A search of multiple databases was conducted. Recreational and higher-level athletes were included. Fourteen articles including 295 athletes (208 male, 87 female) were identified for inclusion (age range 14-66 years, mean 31.2 years). Meniscal pathology was visualized with magnetic resonance imaging and graded on a 1-4 scale (grades 1 and 2 indicating intrasubstance damage, grades 3 and 4 indicating a tear). RESULTS: There was an overall prevalence of 27.2 % (105/386) of knees with intrasubstance meniscal damage (grades 1 and 2), and 3.9 % (15/386) of knees with a tear (grades 3 and 4). When athletes were split into those who participate in pivoting sports versus non-pivoting sports, pivoting athletes showed an overall prevalence of 15.3 % (31/202) of knees with intrasubstance meniscal pathology and 2.5 % (5/202) of knees with a tear. Non-pivoting athletes showed a prevalence of 54.5 % (61/112) of knees with intrasubstance meniscal pathology and 5.4 % (6/112) of knees with a tear. CONCLUSION: The overall prevalence of isolated meniscal pathology in asymptomatic athletes was 31.1 % (27.2 % with intrasubstance meniscal damage and 3.9 % with a meniscal tear). More studies of age-comparable, non-athletic populations are necessary for direct comparison with these groups.

Venous thromboembolism following arthroscopic knee surgery: a current concepts review of incidence, prophylaxis, and preoperative risk assessment.

The purpose of this review was to compile existing knowledge regarding venous thromboembolism (VTE) after arthroscopic knee surgery (AKS). We reviewed the reported incidence, published prophylaxis guidelines, randomized controlled trials (RCT) of prophylaxis, and current prophylaxis practice patterns. In this context we then considered the most appropriate VTE risk assessment model for patients undergoing knee arthroscopy. The existing body of literature regarding VTE and AKS reports a wide range of incidence, often utilizing primary outcome measures with unclear clinical significance: asymptomatic and distal deep vein thrombosis (DVT). Published prophylaxis guidelines provide limited practical guidance and it is unclear how to translate the results of RCTs to clinical practice, as many of the VTE prevented by routine prophylaxis are asymptomatic or distal DVT. Literature regarding actual implementation of pharmacologic prophylaxis following AKS suggests that no consensus exists. Patients undergoing knee arthroscopy would be best managed with the individual model of VTE risk assessment rather than the group model that is applied to hip and knee arthroplasty patients.