The risk of DDH between breech and cephalic-delivered neonates using Graf ultrasonography.

PURPOSE: Developmental dysplasia of the hip (DDH) is one of the most common musculoskeletal disorder in infants. The most significant risk factors include female gender, breech presentation, left hip and family history. In this study, we utilized the Graf method at different time intervals to evaluate both breech-delivered and cephalic-born newborns. The objectives were to compare the incidence of DDH in cephalic and breech-delivered neonates and investigate whether the hip joints of neonates delivered in the breech position exhibit a distinct maturation pattern. MATERIAL AND METHODS: We studied prospectively 618 hip joints (309 newborns). Each hip joint was examined with the Graf method in four time periods as follows: Phase #1 (0-1 weeks), Phase #2 (1-4 weeks), Phase #3 (4-7 weeks), and Phase #4 (7-10 weeks). The α and ß angles for each hip joint were measured, and the hips were classified according to Graf classification. With our statistical analysis within the different phases, we were able to investigate potential variations in the maturation patterns between newborns delivered in the breech and cephalic delivery positions. RESULTS: A significant difference (at the 5% level) was observed in Phase 1 between breech and cephalic-delivered neonates (35.6-8.6%). This difference tended to decrease in next phases (13.6-1% in Phase 2, 2.5-0% in Phase 3 and 1.7-0% in Phase 4). A significant difference (at the 5% level) for cephalic-delivered neonates was also observed between Phase 1 and Phase 4 (8.5-0%), but the percentages were low. Additionally, the breech-delivered had extreme difference in incidence of DDH from Phase 1 to Phase 4 (35.6-11.9%, 2.5%, and 1.7%, respectively). CONCLUSION: It appears that there is an actual difference in the incidence of DDH between breech-delivered and cephalic-delivered neonates, although the difference may be less significant than previously considered. The majority of the breech-delivered neonates that were initially considered as pathological (Phase 1) are, in fact, healthy. This is ascertained in subsequent ultrasound examinations conducted in later phases (Phases 2-4), when the incidence of pathological cases decreases. This could be attributed to potential different maturation pattern between these groups.

Ultrasonographic screening for developmental dysplasia of the hip: the Graf method revisited.

Until the 1980s, the diagnosis of developmental dysplasia of the hip (DDH) was based on clinical examination and radiographic imaging. In 1980, Reinhard Graf developed his own ultrasonographic method for the examination of the infant hip joint. Graf's method evaluates the osseous and cartilaginous coverage of the femoral head by the acetabulum in the infantile hip joint by measuring the angles α and ß. The validity of Graf method is that with these measurements the hip joint is further classified by Graf classification into types I to IV that guide treatment. Currently, Graf method is considered the gold standard examination for the diagnosis of DDH in many European countries. This review article aims to discuss the incidence, risk factors and pathophysiology of DDH, and to emphasize on the Graf method for the evaluation, classification, prevention and further management of this entity.

Orthobiologics: a review.

PURPOSE: The use of biologic materials in orthopaedics (orthobiologics) has gained significant attention over the past years. To enhance the body of the related literature, this review article is aimed at summarizing these novel biologic therapies in orthopaedics and at discussing their multiple clinical implementations and outcomes. METHODS: This review of the literature presents the methods, clinical applications, impact, cost-effectiveness, and outcomes, as well as the current indications and future perspectives of orthobiologics, namely, platelet-rich plasma, mesenchymal stem cells, bone marrow aspirate concentrate, growth factors, and tissue engineering. RESULTS: Currently available studies have used variable methods of research including biologic materials as well as patient populations and outcome measurements, therefore making comparison of studies difficult. Key features for the study and use of orthobiologics include minimal invasiveness, great healing potential, and reasonable cost as a nonoperative treatment option. Their clinical applications have been described for common orthopaedic pathologies such as osteoarthritis, articular cartilage defects, bone defects and fracture nonunions, ligament injuries, and tendinopathies. CONCLUSIONS: Orthobiologics-based therapies have shown noticeable clinical results at the short- and mid-term. It is crucial that these therapies remain effective and stable in the long term. The optimal design for a successful scaffold remains to be further determined.

What do hip fracture patients die from?

Hip fractures in the elderly are associated with an increased mortality rate, even if they are operated within the recommended time window. However, the causes of mortality vary considerably depending on the postoperative period and the patients' comorbidities. In the 30-day postoperative period, the most common causes of death are acute processes such as bacterial and aspiration pneumonia followed by myocardial infarction, cancer, gastrointestinal hemorrhage, stroke, pulmonary embolism, and acute renal failure. In the 6-month and 1-year postoperative period, chronic processes appear to be the most important causes of death, as well as decompensation of patients' chronic diseases. To enhance the literature, we performed this literature review to summarize and discuss the causes of mortality of elderly hip fracture patients depending on the postoperative period that they occur, and possibly to address the question what do hip fracture patients die from? Our aim was to perform an interesting and concise paper that the curious reader will find interesting and informative.

Osteomyelitis of the femur effectively treated with medulloscopy debridement: a case report.

BACKGROUND: Medulloscopy refers to the visualization of the intramedullary canal with an arthroscope, providing access to the infection site without the need for an extensive approach therefore not compromising the surrounding soft tissue. It provides information regarding the extent of the infected endosteal surface of bone, and it allows a thorough debridement of the intramedullary canal in a controlled manner. Therefore, it can be used as an adjunct to traditional open surgical techniques, to perhaps help to visualize hard to see intramedullary areas. MATERIALS AND METHODS: This article reports a patient with chronic osteomyelitis of the distal metaphysis of the femur that was treated successfully with intramedullary debridement through medulloscopy. The sinus tract reaching down to the femoral bone and communicating with the intramedullary canal was excised, and a cortical window was formed through which the arthroscope was inserted and thorough irrigation of the intramedullary canal and excision of necrotic and infected bone was done. A second medulloscopy through the same approach was necessary 3 months later because of persistent infection. RE: SULTS: At 3-year follow-up, the patient was well without any clinical or radiographic evidence of recurrent infection. CONCLUSION: Medulloscopy can be very useful in localized osteomyelitis as an adjunct to traditional surgical techniques; it helps to visualize hard to see intramedullary areas and adequately addresses the infection, while the damage to surrounding soft-tissue is limited.

Knee size chart nomogram for evaluation of tibial tuberosity-trochlear groove distance in knees with or without history of patellofemoral instability.

PURPOSE: Lateralized tibial tubercle is a cause of patellar instability. Before proceeding with reduction of the tibial tubercle-trochlear groove (TT-TG) distance, surgeons prefer to know whether this distance is pathologic. However, the pathological value remains discussed and may vary with the size of the knee. METHODS: We sought to determine variability in the traditional TT-TG distance versus the anthropometric knee size, using dimensions of the distal part of the femur and proximal part of the tibia of 85 CT scans of the knees in two groups of knees, one normal group without history of patellofemoral instability and one pathologic group with history of instability. RESULTS: The average TT-TG distance measured 13 mm in normal knees and 16.4 mm in pathologic knees. The variability in measurements between normal and pathologic knees varied respectively between ± 5 and ± 15 mm, with as consequence absence of threshold value between normal and pathologic knees. These measurements were supplemented by an analysis of a size ratio coefficient. In the normal group without history of instability, linear regression analysis showed that patients with larger knees tended to have higher TT-TG distances and that the values are associated with the mean ML femoro-tibial width (p = 0.014; Pearson coefficient = 0.4). The knees with history of instability also keep proportional increase of TT-TG with the size of the knee as the knees without history of instability. We developed a nomogram to more appropriately represent the normal values for a given size of the knee. Application of the nomographic model on the CT scan TT-TG data of the patients who have knee instability allows the orthopaedic surgeon to associate the TT-TG distance with the knee size and to evaluate the medial transfer corresponding to the knee size. CONCLUSIONS: The average TT-TG distances in normal and pathologic knees were not identical for each size of the knees.

Effects of press-fit biphasic (collagen and HA/ßTCP) scaffold with cell-based therapy on cartilage and subchondral bone repair knee defect in rabbits.

INTRODUCTION: Human spontaneous osteonecrosis of the knee (SPONK) is still challenging as the current treatments do not allow the production of hyaline cartilage tissue. The aim of the present study was to explore the therapeutic potential of cartilage regeneration using a new biphasic scaffold (type I collagen/hydroxyapatite) previously loaded or not with concentrated bone marrow cells. MATERIAL AND METHODS: Female rabbits were operated of one knee to create articular lesions of the trochlea (three holes of 4 × 4mm). The holes were left empty in the control group or were filled with the scaffold alone or the scaffold previously loaded with concentrated bone marrow cells. After two months, rabbits were sacrificed and the structure of the newly formed tissues were evaluated by macroscopic, MRI, and immunohistochemistry analyses. RESULTS: Macroscopic and MRI evaluation of the knees did not show differences between the three groups (p > 0.05). However, histological analysis demonstrated that a higher O'Driscoll score was obtained in the two groups treated with the scaffold, as compared to the control group (p < 0.05). The number of cells in treated area was higher in scaffold groups compared to the control group (p < 0.05). There was no difference for intensity of collagen type II between the groups (p > 0.05) but subchondral bone repair was significantly thicker in scaffold-treated groups than in the control group (1 mm for the control group vs 2.1 and 2.6 mm for scaffold groups). Furthermore, we observed that scaffolds previously loaded with concentrated bone marrow were more reabsorbed (p < 0.05). CONCLUSION: The use of a biphasic scaffold previously loaded with concentrated bone marrow significantly improves cartilage lesion healing.

Open Versus Arthroscopic Mosaicplasty of the Knee: A Cadaveric Assessment of Accuracy of Graft Placement Using Navigation.

PURPOSE: The purpose of this study was to compare an open freehand mosaicplasty technique with an arthroscopic technique for the treatment of osteochondral lesions by measuring the instrument deviation, quantifying this deviation, and providing numerical information on the difference in the outcomes of these techniques. METHODS: Four cadaveric knees were used. Reference markers were attached to the femur, tibia, and donor/recipient site guides. A total of 10 osteochondral grafts were harvested and inserted into recipient sites arthroscopically and 10 similar grafts were inserted freehand. The angles of graft removal and placement were calculated for each of the surgical groups compared. Ostensibly, a navigation system was used as an aid, to measure the graft placement parameters. RESULTS: Statistical analysis revealed that there was no statistically significant difference between the arthroscopic method and the freehand method regarding the angle of graft removal at the donor site (P = .162), recipient site plug removal angle (P = .731), and recipient site graft placement angle (P = .630). In the freehand group, the mean angle of graft removal at the donor site was 12°, the mean angle of recipient site plug removal was 10.7°, and the mean angle of recipient site plug placement was 10.6°. Using the arthroscopic technique, the mean angle of graft removal at the donor site was 17.14°, the mean angle of recipient site plug removal was 12.0°, and the mean angle of recipient site graft placement was 10.14°. CONCLUSIONS: Our study revealed there was no statistically significant difference regarding precision and accuracy during harvesting, recipient site preparation, and plug placement between the 2 techniques. CLINICAL RELEVANCE: Controversy exists whether an open or arthroscopic osteoarticular transfer system (OATS) technique provides superior accuracy. According to our results, there is no statistically significant difference regarding better visualization, precision, and accuracy between the freehand and arthroscopic techniques. However, larger number of specimens are required for study.

Optimizing Hip Replacement Procedure in Cerebral Palsy-Related Spastic Hip Dysplasia: A Case Report.

Cerebral palsy (CP) often results in severe hip issues, disrupting musculoskeletal development and mobility due to problems such as dislocations and contractures, aggravated by spasticity and heightened muscular tone. While total hip arthroplasty (THA) is required in CP patients, the procedure carries high risks due to concerns about dislocation and wear. This study explores a method of intraoperative navigation to precisely execute preoperative strategies for spinopelvic alignment and optimal cup placement. We discuss a case of a 22-year-old male CP patient with bilateral hip dislocations who experienced significant discomfort, impeding mobility and affecting his performance as a Paralympic rower. He underwent bilateral hip replacement surgeries, guided by preoperative gait analysis and imaging, with navigation aiding in accurate acetabular component placement and correction of excessive femoral anteversion using a modular stem. The patient achieved excellent stability in both standing and rowing postures. Overall, computer navigation enhances complex hip repair by facilitating intraoperative data collection and precise execution of preoperative plans. This approach may extend the lifespan of prostheses, particularly by achieving precise acetabular component placement based on spinopelvic alignment principles, thereby offering significant benefits for CP patients undergoing THA.

comparison of postoperative gait parameters after total ankle arthroplasty and ankle fusion: A systematic review.

Ankle pathology, such as severe arthritis, often necessitates surgical intervention to restore mobility and alleviate pain. Two commonly performed procedures for end-stage ankle disease are ankle fusion (AF) and total ankle arthroplasty (TAA). This review aims to compare the impact of AF and TAA on postoperative gait parameters. An extensive search in PubMed, Scopus, and Web of Science electronic databases was conducted with the use of the keywords ("ankle arthrodesis" OR "ankle fusion") AND ("ankle replacement" OR "ankle arthroplasty") AND "gait." Clinical studies in terms of postoperative gait parameters were included in this review. At least one of the following gait parameters, included in gait analysis, should be researched: spatiotemporal variables and joint kinematics and kinetics. An initial search revealed 221 studies. After the removal of duplicates and screening of titles,10 studies (7 prospective and 3 retrospective case series) were included for qualitative analysis. In the majority of studies, there is no significant difference in spatiotemporal parameters, such as walking speed, cadence, stance duration, step length, and stride length among AF and TAA patients. Postoperative sagittal ankle ROM, mainly maximum ankle dorsiflexion angle is significantly higher in TAA patients, while results concerning hip and knee ROM are variable. The comparison of AF and TAA in terms of postoperative gait parameters has shown variable results. In the majority of studies, there is no significant difference in spatiotemporal and kinetic parameters among AF and TAA patients. Further high-quality prospective studies are needed to fully elucidate the comparison of postoperative gait parameters.

Arthroscopic mosaicplasty for osteochondral lesions of the knee: computer-assisted navigation versus freehand technique.

PURPOSE: The purpose of this study was to compare a freehand arthroscopic approach versus mosaicplasty for treatment of osteochondral lesions of the knee with a navigated arthroscopic technique. METHODS: Four whole cadaveric lower limbs were used. A conventional navigation system was used in combination with an autologous osteochondral graft transplantation system (Osteochondral Autograft Transfer System [OATS]; Arthrex, Naples, FL). The congruity of the articular surface was measured with the navigation probe to detect any difference between the surface created by the grafts and the surface of the femoral condyle surrounding them. The angle relates to a line perpendicular to the articular surface. This line is made by the cutting instrument for graft harvesting and insertion and the articular surface. RESULTS: The mean angle of graft harvest was 3.4° (range, 0° to 10°) in the navigated group versus 14.8° (range, 6° to 26°) in the freehand group (P < .0003). The mean angle for recipient-site coring was 1.5° (range, 0° to 5°) in the navigated group versus 12.6° (range, 4° to 17°) in the freehand group (P < .0003). The mean angle of graft placement was 2° (range, 1° to 5°) in the navigated group versus 10.8° (range, 5° to 15°) in the freehand group (P = .0002). The mean protrusion height of the plug was 0.23 mm (range, 0.1 to 0.5 mm; SD, 0.16) in the navigated group versus 0.34 mm (range, 0.0 to 0.7 mm; SD, 0.25) in the freehand group (P = .336). CONCLUSIONS: Computer-assisted arthroscopic mosaicplasty for treatment of osteochondral lesions in the cadaveric model presented in this study allows permanent visualization of the angle of recipient-site preparation, the depth of the donor plug and the recipient plug, and the angle of insertion of the graft at the recipient site. CLINICAL RELEVANCE: This study shows evidence of potentially greater precision and reproducibility of navigated arthroscopic mosaicplasty when compared with an arthroscopic freehand technique in a cadaveric model. However, true clinical outcome benefit will only be elucidated upon performance of appropriate clinical studies.

Computer-assisted navigation in knee surgery.

Although computer-assisted navigation has been used in clinical practice for more than 15 years, it has only recently started to gain acceptance in a variety of orthopedic procedures. Different types of computer-assisted navigation are available, which allow the surgeon to obtain real-time feedback and offer him the potential to decrease intraoperative errors. However, its increased cost and lacking evidence of long-term superiority have made many surgeons skeptical about its clinical usefulness. The scope of this article is to review the clinical applications of computer-assisted navigation in orthopedic surgery of the knee joint.

Developmental Dysplasia of the Hip: A Review.

Developmental dysplasia of the hip (DDH) is the most common musculoskeletal disorder of the infant age. Its incidence ranges from 0.06/1000 to 76.1/1000 live births and is more frequent in female infants. Breech position, family history and firstborn children are the main risk factors for DDH and this disorder is also associated with the presence of other congenital deformities. Anatomically, the acetabulum remains shallow and the femoral head grows in a wrong position. Clinical examination is important and tests such us Barlow and Ortolani give indications only for a part of the spectrum of this entity. Nowadays the sonographic examination is the most accurate option for the diagnosis. Graf classification categorizes the DDH cases in four types, from normal to dislocated hip, by description and measuring specific angles in sonographic examination. The wide usage of ultrasonography has decreased the non-diagnosed or neglected cases; treatment begins immediately in young age and is usually conservative with the usage of devices such as Pavlik harness and hip spica. To enhance the literature, we searched for published studies on DDH, to summarize the pathogenesis and the diagnosis and to discuss the treatment and outcome of the patients with this disorder.

Higher Infection Rate after ACL Reconstruction with Hamstrings Tendon Autografts Compared with Bone Patellar Bone Tendon Autografts: A Review.

Infection after anterior cruciate ligament reconstruction is a rare but devastating complication resulting in a deleterious impact on knee function as well as an increased related cost for treatment and rehabilitation for the patients. There are conflicting reports regarding the rate of infection between bone patellar tendon bone (BPTB) and hamstrings tendon (HT) autografts for anterior cruciate ligament reconstruction. Therefore, we performed this review to summarize all the available data regarding the risk of infection after ACL reconstruction, to provide insight on the infection risk between BPTB and HT autografts, and to discuss current recommendations for the diagnosis and treatment of these infections. The incidence and risk of infection after ACL reconstruction with HT graft is higher compared with BPTB grafts. The most commonly subacute and late infections, quadruple type, need for cannulated instruments for harvesting, size and shape and fixation of the extra-tunnel material of the HT are important risk factors for infection. Combined antibiotics administration and adequate arthroscopic lavage and debridement are the optimal treatments for ACL reconstruction infection. Early diagnosis and treatment is the most important predictor for graft retention, which accounts more commonly for BPTB grafts. The treating physicians should be aware of the higher incidence of infection after ACL reconstruction with HT graft, as well as for the need for a high clinical suspicion for early diagnosis of the infection. These will increase the possibility of eradication of the infection and retention of the graft.

A Lumbar Paravertebral Space Ultrasound Lumbar Plexus Block Technique for Hip Fracture Surgery in the Elderly.

Ultrasound imaging of peripheral nerves is challenging in elderly population. In cases involving the lumbar plexus (LP), we have employed ultrasound imaging and neurostimulation guidance for successful localization and block of the LP. The postero-medial segment of the psoas muscle (PSM), superior to the vertebral body and anterior to the transverse process ("corner pocket") was used as an imaging landmark for the implementation of the LP block. By advancing the needle through the lateral abdominal wall into the "corner pocket" we were afforded a seamless advancement of the needle into the postero-medial segment of the PSM, which is the standard anatomic position of LP in the PSM. Forty-eight patients in whom ultrasound imaging of the LP was not feasible, but the "corner pocket" was clearly depicted were included in the study. LP block characteristics and adverse events were recorded. The LP was localized in 43/48 patients. The average imaging, needling, and performance times to complete the block were 51 sec (range, 6-180 sec), 81 sec (range, 16-236 sec), and 132 sec (range, 24-270 sec), respectively. The median number of needle redirections per patient was 5.5 (range, 1-13). The local anesthetic spread was visualized in the postero-medial segment of the PSM in 39/43 patients. No complications were recorded. The imaging, needling, and performance times, as well as the number of needle passes did not significantly differ between obese and non-obese patients. In conclusion, in cases with challenging ultrasound imaging of the LP, ultrasound-assisted LP block can be accomplished through the lateral abdominal wall by using as an imaging landmark the "corner pocket" at the postero-medial quadrant of the PSM.

Freehand versus navigated glenoid anchor positioning in anterior labral repair.

PURPOSE: Anchor placement on the glenoid rim is challenging with the angle of insertion critical to achieving satisfactory results. Incorrect anchor placement is a common problem. METHODS: Three plastic shoulder models were used. Reference markers were attached in the posterior portion of the acromion. Using the navigation system, reference point data from the glenoid were acquired. An anterior labral lesion of the glenoid was created that extended from the 1 o'clock to the 5 o'clock position. Three suture anchors were placed under arthroscopic guidance without the aid of navigation system (Group A) and with the aid of navigation system (Group B). Deviation from the optimal angle of 45° for anchor placement was measured and compared between the two groups. RESULTS: The mean insertion angles for anchor placement were 45.9° (SD 3.4°, 40.2°-50.4°) and 41.4° (SD 3.9°, 33.1°-47.6°) in the freehand (Group A) and navigated (Group B) groups, respectively. There was a statistically significant difference between the groups (P < 0.05). The mean deviation (from the optimal angle) was 4.2° (SD 3.2°, 0.0°-11.9°) and 2.8° (SD 2.2°, 0.2°-8.4°) in the freehand and navigated groups, respectively. CONCLUSION: Navigation systems may improve the accuracy of glenoid anchor placement amongst low-volume shoulder surgeons. However, it does not provide any significant advantage over the freehand technique in a plastic shoulder model. Constant multiplanar visualization throughout anchor placement as facilitated by navigation made the procedure more manageable, even for an experienced surgeon.

Echinococcosis of the spine.

Echinococcosis or hydatid disease affecting the spine is an uncommon manifestation of Echinococcus granulosus infection of the spine.More commonly found in endemic areas, it causes significant morbidity and mortality as it grows slowly and produces symptoms mainly by compressing the spinal cord.As diagnostic methods are non-specific, diagnosis and management are usually delayed until the disease is advanced, thereby therapy is usually unlikely.Treatment is usually surgical, aiming at cyst excision, spinal cord decompression and spinal stabilization.This article summarizes the clinical findings of echinococcosis of the spine, discusses the specific laboratory and diagnostic findings, lists the current treatment options, and reviews the patients' outcomes.The aim is to prompt clinicians to be aware of the possibility of echinococcosis as a possible diagnosis in endemic areas. Cite this article: EFORT Open Rev 2021;6:288-296. DOI: 10.1302/2058-5241.6.200130.

Open wedge valgus tibial osteotomies: affecting the distinct ACL bundles.

Valgus alignment affects the biomechanical behavior of the ACL, resulting in an increase of the in situ forces in the posterolateral (PL) bundle of the graft. The amount of valgus alignment creating such effects on the force remains unclear. Furthermore, the mechanistic rational for the increase in situ forces on the PL bundle when compared with the AM during the valgus osteotomy remained unclear. We hypothesized that increasing valgisation of the knee results in significantly increased obliquity and a resulting increasing elongation pattern and apparent strain of the PL bundle compared to the AM bundle. Six cadaver legs were used utilizing two commercial navigation systems including navigated high tibial osteotomy (HTO) and ACL measurements simultaneously. ACL footprints were registered for the central and identified AM and PL bundle. A stepwise oblique open wedge osteotomy was performed for 7.5° and 15° valgisation. Length changes and coronal plane obliquity were determined at 0° and 30° flexion. The apparent strain for each fiber was calculated. Valgisation significantly affects the length and obliquity of the PL portion of ACL. Valgisation of 7.5° appears to be a threshold for affecting PL length and obliquity without significant changes compared to 15°. The mean apparent strain for the PL bundle increases up to 14% with a 15° osteotomy in full extension, compared to 4% for the central and 2% for the AM bundle. HTO should be done prior to fixation the ACL graft in combined procedures as valgisation does affect graft length. Relative alignment influence on obliquity and length of the PL bundle should be considered in valgus knees.

Adjustable cutting blocks for computer-navigated total knee arthroplasty: a cadaver study.

Computer-navigation in total knee arthroplasty has been reported to increase accuracy but also procedure duration. We compared surgical time and precision using a novel adjustable cutting block vs freehand navigation with conventional blocks on 12 bilateral cadaver tibiae. The mean time required was significantly less to position the adjustable block than the conventional block (2 minutes 10 seconds vs 6 minutes 35 seconds, P = .006). Guide positioning precision (standard deviation) for the adjustable block vs conventional block was as follows: varus/valgus, 0.24 degrees vs 1.16 degrees (P = .015); posterior slope, 0.35 degrees vs 0.74 degrees (P = .13); and cut height, 0.37 vs 1.41 mm (P = .010). There were no significant differences in the final bone cut accuracy between the 2 groups. The use of adjustable cutting blocks simplifies navigated procedures and may reduce the time required to perform a navigated total knee arthroplasty.

Superiority of synovial membrane mesenchymal stem cells in chondrogenesis, osteogenesis, myogenesis and tenogenesis in a rabbit model.

Engineering complex tissues is perhaps the most ambitious goal of all tissue engineers. Despite significant advances in tissue engineering, which have resulted in successful engineering of simple tissues such as skin and cartilage, there are a number of challenges that remain in engineering of complex, hybrid tissue structures, such as osteochondral tissue. Mesenchymal stem cells (MSCs) have the capacity to highly proliferate in an undifferentiated state and the potential to differentiate into a variety of different lineages, providing a promising single cell source to produce multiple cell types. MSC obtained from adult human contribute to the regeneration of mesenchymal tissues such as bone, cartilage, fat, muscle, tendon and marrow stroma. In the present study, the regeneration capacity of multipotent MSCs derived from different tissues in the rabbit were compared. Specifically the aim of this study was to isolate and characterize rabbit adult stem cell populations from bone marrow, adipose, synovial membrane, rotator cuff, ligament and tendon and assess their cell morphology, growth rate, cell surface markers and differentiation capacity. MSCs derived from synovial membrane showed superiority in terms of chondrogenesis, osteogenesis, myogenesis and tenogenesis, suggesting that synovial membrane-derived MSCs would be a good candidate for efforts to regenerate musculoskeletal tissues.