Impact of bone and cartilage segmentation from CT and MRI on both bone forearm osteotomy planning

INTRODUCTION

The use of MRI scans for pre-operative surgical planning of forearm osteotomies provides additional information of joint cartilage and soft tissue structures and reduces radiation exposure in comparison with the use of CT scans. In this study, we investigated whether using 3D information obtained from MRI with and without cartilage information leads to a different outcome of pre-operative planning.

METHODS

Bilateral CT and MRI scans of the forearms of 10 adolescent and young adult patients with a unilateral bone deformation were acquired in a prospective study. The bones were segmented from CT and MRI, and cartilage only from MRI. The deformed bones were virtually reconstructed, by registering the joint ends to the healthy contralateral side. An optimal osteotomy plane was determined that minimized the distance between the resulting fragments. This process was performed in threefold: using the CT and MRI bone segmentations, and the MRI cartilage segmentations.

RESULTS

Comparison of bone segmentation from MRI and CT scan resulted in a 0.95 ± 0.02 Dice Similarity Coefficient and 0.42 ± 0.07 mm Mean Absolute Surface Distance. All realignment parameters showed excellent reliability across the different segmentations. However, the mean differences in translational realignment between CT and MRI bone segmentations (4.5 ± 2.1 mm) and between MRI bone and MRI bone and cartilage segmentations (2.8 ± 2.1 mm) were shown to be clinically and statistically significant. A significant positive correlation was found between the translational realignment and the relative amount of cartilage.

CONCLUSION

This study indicates that although bone realignment remained largely similar when using MRI with and without cartilage information compared to using CT, the small differences in segmentation could induce statistically and clinically significant differences in the osteotomy planning. We also showed that endochondral cartilage might be a non-negligible factor when planning osteotomies for young patients.

Insights and trends review: the role of three-dimensional technology in upper extremity surgery

The use of three-dimensional (3-D) technology in upper extremity surgery has the potential to revolutionize the way that hand and upper limb procedures are planned and performed. 3-D technology can assist in the diagnosis and treatment of conditions, allowing virtual preoperative planning and surgical templating. 3-D printing can allow the production of patient-specific jigs, instruments and implants, allowing surgeons to plan and perform complex procedures with greater precision and accuracy. Previously, cost has been a barrier to the use of 3-D technology, which is now falling rapidly. This review article will discuss the current status of 3-D technology and printing, including its applications, ethics and challenges in hand and upper limb surgery. We have provided case examples to outline how clinicians can incorporate 3-D technology in their clinical practice for congenital deformities, management of acute fracture and malunion and arthroplasty.

Cold ablation robot‐guided laser osteotomy in hand, wrist and forearm surgery—A feasibility study

Introduction

Traditional bone surgery using saws and chisels is associated with direct contact of instruments with the bone causing friction, heat and pressure and hence, damaging the bone and the surrounding soft tissues.

Method

Cold ablation laser osteotomy offers new possibilities to perform corrective osteotomies in the field of bone surgery. We introduce the technology of navigated cold ablation robot‐guided laser osteotomy, present potential applications, and preliminary pre‐clinical cadaver test results in the field of hand‐, wrist‐ and forearm surgery.

Results

The cadaver tests showed first promising results for corrections in all planes and axes using different cutting patterns.

Conclusion

Cold ablation laser osteotomy seems to be a feasible new method to perform osteotomies in the field of hand‐, wrist‐ and forearm surgery. Primary osseous stability could be achieved using various cutting patterns which could lead to reduction of the amount of hardware required for osteosynthesis. Further tests are required to proof the latter and precision.

The malunion of distal radius fracture: Corrective osteotomy through planning with prototyping in 3D printing

INTRODUCTION

Distal radius fractures (DRF) are among the most frequent in the body. About one third of these fractures can result in malunion with restriction of movement and pain in the wrist, the treatment in these cases consists of corrective osteotomy of the deformity. Due to its three-dimensional (3D) complexity, careful preoperative planning is a fundamental step in correction. The prototyping from the 3D reconstruction of the computed tomography of the affected wrist, allows the real understanding of the deformity.

METHODS

Patients with malunion of the distal radius with indication for surgical treatment, from December 2019, were included in the group of corrective osteotomies through planning with prototyping in 3D printing. The postoperative functional outcome was assessed by the Disabilities of the Arm, Shoulder and Hand Score (DASH) and visual analogue scale (VAS). Radiographic data including radial inclination, volar tilt and joint step were recorded from standard posteroanterior and lateral radiographic views.

RESULTS

A total of 9 patients were included. The mean age was 47 years. The average postoperative DASH value of the patients was 24.9 and VAS was 3.6. Radiographically, the palmar tilt had an average improvement of 25.22°, and the radial inclination had an average improvement of 2°.

CONCLUSION

Corrective osteotomy through planning with prototyping in 3D printing is an effective method of treating symptomatic distal radius malunions. The possibility of performing the osteotomy in a 3D model, simulating the surgery, making the procedure more predictable.