Variation characteristics of stress distribution in the subchondral bone of the knee joint of judo athletes with long-term stress changes

OBJECTIVE

To investigate the distribution of bone density in the subchondral bone tissue of the knee joint due to the mechanical stress load generated by judo, the bone tissue volume of different densities and the bone remodeling characteristics of the subchondral bone of the knee joint.

METHODS

CT imaging data of the knee joint were collected from 15 healthy individuals as controls and 15 elite judo athletes. Firstly, they were processed by the CTOAM technique, and secondly, the distribution pattern of high-density areas of the knee joint was localized using nine anatomical regions. In addition, three tomographic images were selected in the sagittal, coronal, and axial 2D image windows to observe the distribution of different densities of bone tissue. Finally, the percentage of bone tissue volume (%BTV) and bone remodeling trend of bone tissues with different densities were determined.

RESULTS

In this study, high-density areas were found in the 4th, 5th, and 6th regions of the articular surface of the distal femur and the 1st, 2nd, 3rd, 4th, 5th, 6th, 7th and 8th regions of the tibial plateau in judo athletes; the distribution of high-density areas on the articular surface of the distal femur in control subjects was similar with judo athletes, and high-density areas were mainly found in the 4th and 5th regions of the tibial plateau. The %BTV of low (401-500HU in the distal femur; 301-400 HU and 401-500HU in the tibial plateau), moderate, and high bone density was higher in judo athletes than in controls in the subchondral bone of the distal femur and tibial plateau (P< 0.05).

CONCLUSION

The history of compressive stresses, struck stresses, soft tissue tension and pull, self-gravity and intra-articular stress loading generated by the lower limb exercise technique of judo leads to specific forms of stress distribution and bone tissue remodeling in the subchondral bone tissue within the distal femur and tibia plateau.

Osteochondral Allograft Reconstruction of the Tibia Plateau for Posttraumatic Defects-A Novel Computer-Assisted Method Using 3D Preoperative Planning and Patient-Specific Instrumentation

Background  Surgical treatment of posttraumatic defects of the knee joint is challenging. Osteochondral allograft reconstruction (OCAR) is an accepted procedure to restore the joint congruity and for pain relief, particularly in the younger population. Preoperative three-dimensional (3D) planning and patient-specific instrumentation (PSI) are well accepted for the treatment of posttraumatic deformities for several pathologies. The aim of this case report was to provide a guideline and detailed description of the preoperative 3D planning and the intraoperative navigation using PSI in OCAR for posttraumatic defects of the tibia plateau. We present the clinical radiographic results of a patient who was operated with this new technique with a 3.5-year follow-up.

Materials and Methods  3D-triangular surface models are created based on preoperative computer tomography (CT) of the injured side and the contralateral side. We describe the preoperative 3D-analysis and planning for the reconstruction with an osteochondral allograft (OCA) of the tibia plateau. We describe the PSI as well as cutting and reduction techniques to show the intraoperative possibilities in posttraumatic knee reconstructions with OCA.

Results  Our clinical results indicate that 3D-assisted osteotomy and OCAR for posttraumatic defects of the knee may be beneficial and feasible. We illustrate the planning and execution of the osteotomy for the tibia and the allograft using PSI, allowing an accurate anatomical restoration of the joint congruency.

Discussion  With 3D-planning and PSI the OCAR might be more precise compared with conventional methods. It could improve the reproducibility and might allow less experienced surgeons to perform the precise and technically challenging osteotomy cuts of the tibia and the allograft. Further, this technique might shorten operating time because time consuming intraoperative steps such as defining the osteotomy cuts of the tibia and the allograft during surgery are not necessary.

Conclusion  OCAR of the tibia plateau for posttraumatic defects with 3D preoperative planning and PSI might allow for the accurate restoration of anatomical joint congruency, improve the reproducibility of surgical technique, and shorten the surgery time.

Morphometric analysis of medial and lateral tibia plateau and adaptability with Oxford partial knee replacement in a Japanese population

AIMS

In unicompartmental knee arthroplasty (UKA), tibial components must be correctly sized and positioned so that tibial cut surfaces are well covered without marked under- or overhang with impingement of the surrounding soft tissue. We used morphometric data of both medial and lateral tibial plateaus separately to plan UKA and evaluated the compatibility of the measurement data to the dimensions of six currently available tibial prostheses in a Japanese population.

MATERIALS AND METHODS

Using computed tomography, we preoperatively examined 60 patients (30 medial and 30 lateral osteoarthritis (OA)) scheduled for primary UKA at our hospital between 2013 and 2017. Each tibial cutting surface was measured in the transverse plane at 2 mm below the respective joint line. We used anteroposterior and mediolateral length to calculate the mediolateral length/anteroposterior ratio of both medial and lateral compartments. We then compared measurements across six current UKA systems: Oxford fixed tibia and fixed lateral tibia, Triathlon, TRIBRID, JOURNEY UNI, and HLS Uni Evolution.

RESULTS

We found no significant differences in morphometric data between the medial and the lateral OA. The cutting surface of lateral plateau, however, had smaller anteroposterior dimensions, greater mediolateral length, and higher mediolateral length/anteroposterior ratio than those of medial plateau. Therefore, in this Japanese population-based study, Oxford lateral tibia had good compatibility with the measurement data of lateral compartments.

CONCLUSIONS

Lateral compartments had lower anteroposterior length, greater mediolateral length, and higher mediolateral length/anteroposterior ratio than those of medial compartments. We, therefore, strongly recommend using Oxford fixed lateral tibia for lateral OA over other current tibial prostheses because of superior coverage.

Physiotherapy after tibial plateau fracture fixation: A systematic review of the literature

Background

Tibial plateau fractures are frequent injuries that orthopaedic surgeons face. It has been reported that they have a significant negative impact on the patients' lives, decreasing their quality of live, keeping them of work for long periods of time and reducing their activity levels.

Aim

Interestingly, there is not enough focus in the literature about the post-operative rehabilitation of these patients. The aim of the present review is to investigate this field of the literature and try to give answers in four main questions: the range of motion exercises post-surgery, the immobilisation, the weight-bearing status and the ongoing rehabilitation.

Materials and Methods

A literature search was conducted using the PubMed and the Google Scholar search engines. A total of 39 articles met the criteria to be included in the study.

Results

The literature about this subject is scarce and controversial. Early range of motion exercises should be encouraged as soon as possible after the procedure. The immobilisation after plate fixation does not seem to be correlated with any benefits to the patients. The weight-bearing status of the patients was the most controversial in the literature with the early weight-bearing gaining ground at the most recent studies. Tibia plateau fractures can have significant impact on the patients' lives, so ongoing rehabilitation with focus on quadriceps strengthening and proprioception exercises is recommended.

Conclusion

The present literature review illuminates the controversy that exists in the literature about the physiotherapy following tibia plateau fracture fixation. Early range of motion exercises and early weight bearing should be encouraged. Immobilisation does not seem to provide any benefit. Ongoing rehabilitation should be considered with the view of better clinical outcomes.

Reconstruction of the lateral tibia plateau fracture with a third triangular support screw: A biomechanical study

Background

Split fractures of the lateral tibia plateau in young patients with good bone quality are commonly treated using two minimally invasive percutaneous lag screws, followed by unloading of the knee joint. Improved stability could be achieved with the use of a third screw inserted either in the jail-technique fashion or with a triangular support screw configuration. The aim of this study was to investigate under cyclic loading the compliance and endurance of the triangular support fixation in comparison with the standard two lag-screw fixation and the jail technique.

Methods

Lateral split fractures of type AO/OTA 41-B1 were created on 21 synthetic tibiae and subsequently fixed with one of the following three techniques for seven specimens: standard fixation by inserting two partially threaded 6.5 mm cannulated lag screws parallel to each other and orthogonal to the fracture plane; triangular support fixation-standard fixation with one additional support screw at the distal end of the fracture at 30° proximal inclination; and jail fixation-standard fixation with one additional orthogonal support screw inserted in the medial nonfractured part of the bone. Mechanical testing was performed under progressively increasing cyclic compression loading. Fragment displacement was registered via triggered radiographic imaging.

Results

Mean construct compliance was 3.847 × 10^-3 mm/N [standard deviation (SD) 0.784] for standard fixation, 3.838 × 10^-3 mm/N (SD 0.242) for triangular fixation, and 3.563 × 10^-3 mm/N (SD 0.383) for jail fixation, with no significant differences between the groups (p = 0.525). The mean numbers of cycles to 2 mm fragment dislocation, defined as a failure criterion, were 12,384 (SD 2267) for standard fixation, 17,708 (SD 2193) for triangular fixation, and 14,629 (SD 5194) for jail fixation. Triangular fixation revealed significantly longer endurance than the standard one (p = 0.047).

Conclusion

Triangular support fixation enhanced interfragmentary stability at the ultimate stage of dynamic loading. However, the level of improvement seems to be limited and may not legitimate the intervention with an additional third screw.