More passive internal tibial rotation with posterior cruciate ligament retention than with excision in a medial pivot TKA implanted with unrestricted caliper verified kinematic alignment

Purpose Excision of the posterior cruciate ligament (PCL) is recommended when implanting a medial pivot (MP) total knee arthroplasty (TKA) to reduce the risk of limiting flexion by over-tensioning the flexion space. The present study determined whether PCL retention (1) limits internal tibial rotation and (2) causes anterior lift-off of the insert in 90° flexion after implantation of an MP design with unrestricted caliper verified kinematic alignment (KA). Methods Four surgeons implanted an MP TKA design with medial ball-in-socket and lateral flat tibial insert in ten fresh-frozen cadaveric knees. Before and after PCL excision, trial inserts with medial goniometric markings measured the angular I–E tibial orientation relative to the trial femoral component's medial condyle in extension and at 90° flexion, and the surgeon recorded the occurrence of anterior lift-off of the insert at 90° flexion. Results PCL retention resulted in greater internal tibial rotation than PCL excision, with mean values of 15° vs 7° degrees from maximum extension to 90° flexion, respectively (p < 0.0007). At 90° flexion, no TKAs with PCL retention and one TKA with PCL excision had anterior lift-off of the insert (N.S.). Conclusions This preliminary study of ten cadaveric knees showed that PCL retention restored more passive internal tibial rotation than PCL excision with a negligible risk of anterior lift-off. However, in vivo analysis from multiple authors with a larger sample size is required to recommend PCL retention with an MP TKA design implanted with unrestricted caliper verified KA.

Morphological and morphometric studies on the scapula and humerus of Binturong (Arctictis Binturong)

Natural Habitat of Binturong is the forest remnant of South-east Asia. Common characteristic features of a Binturong are its shout legs, thick black body coat and prehensile tail. After collecting the samples from Aizawl Zoological Park, Mizoram with permission from the Department of Environment, Forest and Climate change, Government of Mizoram, those were macerated by the combination of boiling hot water and HODifferent morphometric parameters of scapula and humerus were measured. Scapula of Binturong was a flat almost square shaped bone with similar width in both dorsal and ventral border with a wide scapular neck, average circumference of which is around 8.04 cm. Average maximum length and width of the scapula of Binturong was 8.81 cm and 6.56 cm, respectively. A small foramen was seen at the neck of the scapula perforating the ventral portion of the scapular spine. Average maximum total length of Binturong Humerus was 12.81 cm. Proximal extremity of the humerus carries a caudally present oval shaped head, average maximum width of which is about 2.05cm. Distal extremity of the Binturong humerus is consists of a supracondylar foramen, a radial fossa, a olecranon fossa, lateral and medial condyle and epicondyle. Since not much work has been done on the related field in this particular animal, therefore this present study was conducted to get the baseline data about the two bones of forelimb in Binturong, which can play a predominant role in disease diagnosis, treatments and other applied fields of veterinary biology.

Adjusting Insert Thickness and Tibial Slope Do Not Correct Internal Tibial Rotation Loss Caused by PCL Resection: In Vitro Study of a Medial Constraint TKA Implanted with Unrestricted Calipered Kinematic Alignment

Most medial stabilized (MS) total knee arthroplasty (TKA) implants recommend excision of the posterior cruciate ligament (PCL), which eliminates the ligament's tension effect on the tibia that drives tibial rotation and compromises passive internal tibial rotation in flexion. Whether increasing the insert thickness and reducing the posterior tibial slope corrects the loss of rotation without extension loss and undesirable anterior lift-off of the insert is unknown. In 10 fresh-frozen cadaveric knees, an MS design with a medial ball-in-socket (i.e., spherical joint) and lateral flat insert was implanted with unrestricted calipered kinematic alignment (KA) and PCL retention. Trial inserts with goniometric markings measured the internal–external orientation relative to the femoral component's medial condyle at maximum extension and 90 degrees of flexion. After PCL excision, these measurements were repeated with the same insert, a 1 mm thicker insert, and a 2- and 4-mm shim under the posterior tibial baseplate to reduce the tibial slope. Internal tibial rotation from maximum extension and 90 degrees of flexion was 15 degrees with PCL retention and 7 degrees with PCL excision (p < 0.000). With a 1 mm thicker insert, internal rotation was 8 degrees (p < 0.000), and four TKAs lost extension. With a 2 mm shim, internal rotation was 9 degrees (p = 0.001) and two TKAs lost extension. With a 4 mm shim, internal rotation was 10 degrees (p = 0.002) and five TKAs lost extension and three had anterior lift-off. The methods of inserting a 1 mm thicker insert and reducing the posterior slope did not correct the loss of internal tibial rotation after PCL excision and caused extension loss and anterior lift-off in several knees. PCL retention should be considered when using unrestricted calipered KA and implanting a medial ball-in-socket and lateral flat insert TKA design, so the progression of internal tibial rotation and coupled reduction in Q-angle throughout flexion matches the native knee, optimizing the retinacular ligaments' tension and patellofemoral tracking.

Spacer-based gap balancing is useful in total knee arthroplasty: a 3-year follow-up of a retrospective study

Background Which technique, gap balancing or measured resection, can obtain better femoral component alignment and soft tissue balance in total knee arthroplasty (TKA) is still controversial. This study aimed to determine whether the gap balancing technique using a modified spacer block in TKA can result in better postoperative clinical outcomes than the measured resection technique. Methods A total of 124 patients who underwent consecutive primary TKA between May 2016 and August 2018 were retrospectively reviewed. The gap balancing technique assisted by a modified spacer block was used in 61 patients, and the measured resection technique was used in 63 patients. The surgical, imaging and knee function outcomes of the two groups were compared. Results The thickness of the posterior medial condyle bone resection using the modified spacer block tool in gap balancing was significantly larger than that of the MR technique (P = 0.001). Compared with the measured resection group, the gap balancing group had a greater external rotation resection angle of the femur (4.06 ± 1.10° vs. 3.19 ± 0.59°, P < 0.001°). Despite these differences, the mean ROM, KSS scores, and WOMAC scores at the 6-week, 1-year, and 2-year follow-ups were not significantly different. Postoperatively, there was no significant difference between the two groups in mechanical axis measurements (P = 0.275), the number of HKA outliers (P = 0.795) or the joint line displacement (P = 0.270). Conclusion The functional outcomes of the gap balancing technique based on the modified spacer are similar to those of measured resection at 3 years. Compared with the MR technique, the GB technique resulted in a greater external rotation resection angle and thicker posterior medial condylar cuts in TKA with knee varus.

Morphometric study of upper end of tibia and its implications in total knee replacement

: Knee deformities can be reliably assessed by using morphometric parameters of upper end of tibia. Total knee arthroplasties are done to treat many types of arthritis and injuries involving knee joint. So, there is a need to have data of various morphometric parameters of upper end of tibia in order to have better surgical outcomes. The present study was attempted to provide values of different parameters in the population of Bihar.: The present study was a cross-sectional and prospective study conducted on 50 tibia of unknown gender and age in the Department of Anatomy, Indira Gandhi Institute of Medical Sciences, Patna. Fully ossified, dried, macerated and thoroughly cleaned tibia were taken to measure different parameters of upper end with the help of digital vernier calliper. The data thus obtained were tabulated and analysed statistically using Microsoft excel software.: It was found that the diameters of medial condyle were more than the lateral condyle. The antero-posterior diameter was more than the transverse diameter in case of both the condyles. But the difference between the right and the left side was not statistically significant.: The present study will help in providing a baseline data for designing of the prosthesis used in total knee replacement surgeries. It will also be helpful to anthropologists and forensic experts.

Hypermobility of ulnar nerve does not affect throwing performance (122)

Objectives: Ulnar nerve neuropathy around the elbow is a common pathology in throwing athletes, and occurs due to many factors including valgus elbow, and ulnar nerve hypermobility. For patients with ulnar nerve neuropathy, anterior transposition of the ulnar nerve is common procedures. Meanwhile, Ulnar nerve hypermobility has been reported to be present in 2% to 47% of asymptomatic individuals. However, no studies have investigated the rate of ulnar nerve hypermobility in throwing athletes, and the relationship between ulnar nerve mobility, and clinical symptom and throwing performance. This study was designed to classify the sonographic assessment for the mobility of the ulnar nerve compared to physical evaluation, and to determine whether ulnar nerve hypermobility is associated with clinical symptoms and throwing performance in baseball players. We investigated ulnar nerve hypermobility using ultrasound to evaluate the relationship between the ulnar nerve hypermobility and clinical sign including throwing performance in college baseball players. Methods: 138 elbows in 69 college baseball players were examined. Each participant was queried regarding symptoms attributable to the ulnar nerve. In addition, structural measurements consisting of the tinel test and elbow flexion compression testing were examined. Sonographic examiners were, unaware of reported symptoms, independently performed a standardized examination of both elbows to assess ulnar nerve hypermobility. For sonographic assessment, the ultrasound probe was located at the medial condyle of the humerus to visualize the ulnar nerve in short-axis view in the extended elbow position. During extension to flexion of the elbow, the mobility of ulnar nerves was assessed, and categorized as stable, or hypermobile, which was further subclassified as subluxation, or dislocation (Figure 1A, 1B, 1C). Pared t-test was used to compare the mobility of the ulnar nerve between throwing and non-throwing sides. Fisher’s exact test was used to assess the relationship between physical exams and the mobility of the ulnar nerve. Values of p<0.05 were considered statistically significant. Results: Ulnar nerve hypermobility was identified in 54 (78.3%) of the 69 elbows in throwing side. Meanwhile, hypermobility was 53 (76.8%) in non-throwing side without significant difference, compared to non-throwing side. Elbows with nerve hypermobility did not experience a higher prevalence of subjective symptoms (snapping, pain, and tingling) than did elbows with stable nerves. Provocative physical examination testing for ulnar nerve irritability, however, showed consistent trends toward heightened irritability in hypermobile nerves (p = 0.04 to 0.16). Demographic data and anatomic measurements were similar between the subjects with stable nerves and those with hypermobile nerves. Additionally, all participants did not show decrease of throwing performance. Conclusions: Ulnar nerve hypermobility occurs in over half of the baseball players in throwing and non-throwing sides. Utilizing a standardized sonographic examination, a diagnosis of ulnar nerve hypermobility can be established with substantial interobserver reliability. In baseball players, ulnar nerve hypermobility does not appear to be associated with an increased symptomatology attributable to the ulnar nerve and throwing performance. Anterior transplantation of ulnar nerve may not be needed for baseball players with ulnar nerve neuropathy.

Clinical examination of various jaw fractures and evaluation of open and closed reductions: Six case reports

Aim: This study aims to present the fracture types and treatment methods of jaw fracture cases that presented at our center. Methodology: Of six presenting cases, two were angulus, one was parasymphysis, three were subcondylar, and one was a medial condyle fracture only. All patients were evaluated both clinically and radiologically by CT of the atlanto-occipital joint. We managed two of the mandibular fractures with open and closed reduction (mixed) and four with closed reduction only. Dislocation was observed in only two patients. Internal fixation was performed using either mini plates (Medartis, Basel, Switzerland) or mini-screws. All cases united within three weeks to three months. Results: After analyzing the epidemiology of six fractures and the outcomes of the surgical treatment, as well as assessing the complications related to the surgical procedures, it was determined that in cases with dislocation, bimaxillary fixation should be applied as a maintenance to open reduction therapy. In cases without dislocation, bimaxillary fixation only is sufficient. Conclusion: An analysis of dislocation conditions according to fracture type supports that the incidence of dislocation is low in condyle fractures. Conclusion: An analysis of dislocation conditions according to fracture type supports that the incidence of dislocation is low in condyle fractures. How to cite this article: Özüdoğru S, Başaran MM, Ataözden T. Clinical examination of various jaw fractures and evaluation of open and closed reductions: Six case reports. Int Dent Res 2021;11(Suppl.1):274-8. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.40 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Intraoperative Fractures of the Tibia and Femur in Knee Revision Surgery

Intra-operative fractures in knee revision surgery are relatively rare and have not been well studied. They may occur during joint exposition, removal of the prosthesis or cement, or implantation of trial or original components. The fractures affect both the metaphyseal area and diaphysis of the tibia and femur. Tibial fractures are slightly more common than femur fractures. On the femur, the medial condyle is most frequently affected, followed by the femur diaphysis. The use of non-cemented stems is associated with a greater risk of intra-operative diaphyseal fractures than that of cemented stems. Overall, women and patients with an osteopenic bone structure have a higher risk of fractures. It is common that fractures are diagnosed post-operatively. In these cases, conservative therapy may be successful, depending on the stability of the prosthesis and bones. The most common surgical fixation options are cerclages and screws, followed by stem extensions for bridging the fracture. Plate fixation or use of strut grafts are also sensible therapy options. Overall, intraoperative fractures have a high healing potential with stable and good joint function. The revision rate is still 15%, which is most often caused by peri-prosthetic infection.