Computed tomography and structured light imaging guided orthopedic navigation puncture system: effective reduction of intraoperative image drift and mismatch.

Background: Image-guided surgical navigation systems are widely regarded as the benchmark for computer-assisted surgical robotic platforms, yet a persistent challenge remains in addressing intraoperative image drift and mismatch. It can significantly impact the accuracy and precision of surgical procedures. Therefore, further research and development are necessary to mitigate this issue and enhance the overall performance of these advanced surgical platforms. Objective: The primary objective is to improve the precision of image guided puncture navigation systems by developing a computed tomography (CT) and structured light imaging (SLI) based navigation system. Furthermore, we also aim to quantifying and visualize intraoperative image drift and mismatch in real time and provide feedback to surgeons, ensuring that surgical procedures are executed with accuracy and reliability. Methods: A CT-SLI guided orthopedic navigation puncture system was developed. Polymer bandages are employed to pressurize, plasticize, immobilize and toughen the surface of a specimen for surgical operations. Preoperative CT images of the specimen are acquired, a 3D navigation map is reconstructed and a puncture path planned accordingly. During surgery, an SLI module captures and reconstructs the 3D surfaces of both the specimen and a guiding tube for the puncture needle. The SLI reconstructed 3D surface of the specimen is matched to the CT navigation map via two-step point cloud registrations, while the SLI reconstructed 3D surface of the guiding tube is fitted by a cylindrical model, which is in turn aligned with the planned puncture path. The proposed system has been tested and evaluated using 20 formalin-soaked lower limb cadaver specimens preserved at a local hospital. Results: The proposed method achieved image registration RMS errors of 0.576 ± 0.146 mm and 0.407 ± 0.234 mm between preoperative CT and intraoperative SLI surface models and between preoperative and postoperative CT surface models. In addition, preoperative and postoperative specimen surface and skeletal drifts were 0.033 ± 0.272 mm and 0.235 ± 0.197 mm respectively. Conclusion: The results indicate that the proposed method is effective in reducing intraoperative image drift and mismatch. The system also visualizes intraoperative image drift and mismatch, and provides real time visual feedback to surgeons.

More potential uses of specific perforator flaps in the calf - A cadaveric study on the subdermal vascular structure of the lower leg.

BACKGROUND: The perforator flap has garnered significant interest since its inception due to its advantage of not needing a vascular network at the deep fascial level. Perforator flaps are commonly utilized in different flap transplant surgeries, and the thigh flap is presently the most widely used perforator flap. Is it possible for the calf to replace the thigh as a more suitable site for harvesting materials? Currently, there is a lack of relevant anatomical research. This study aims to address this question from an anatomical and imaging perspective. METHODS: This study used cadavers to observe the branches and courses of perforators on the calf and the distribution of skin branches using microdissection techniques, digital X-ray photography, and micro-computed tomography techniques. RESULTS: The perforators had three main branches: the vertical cutaneous branch, the oblique cutaneous branch, and the superficial fascial branch. The superficial fascial branch traveled in the superficial fascia and connected with the nearby perforators. The vertical and oblique cutaneous branches entered the subdermal layer and connected with each other to create the subdermal vascular network. CONCLUSIONS: We observed an intact calf cutaneous branch chain between the cutaneous nerve and the perforator of the infrapopliteal main artery at the superficial vein site. Utilizing this anatomical structure, the calfskin branch has the potential to serve as a substitute for thigh skin flap transplantation and may be applied to perforator flap transplantation in more locations.

Comparison of biomechanical parameters of two Chinese cervical spine rotation manipulations based on motion capture and finite element analysis.

Objective: The purpose of this study was to obtain the stress-strain of the cervical spine structure during the simulated manipulation of the oblique pulling manipulation and the cervical rotation-traction manipulation in order to compare the mechanical mechanism of the two manipulations. Methods: A motion capture system was used to record the key kinematic parameters of operating the two manipulations. At the same time, a three-dimensional finite element model of the C0-T1 full healthy cervical spine was established, and the key kinematic parameters were loaded onto the finite element model in steps to analyze and simulate the detailed process of the operation of the two manipulations. Results: A detailed finite element model of the whole cervical spine including spinal nerve roots was established, and the validity of this 3D finite element model was verified. During the stepwise simulation of the two cervical spine rotation manipulations to the right, the disc (including the annulus fibrosus and nucleus pulposus) and facet joints stresses and displacements were greater in the oblique pulling manipulation group than in the cervical rotation-traction manipulation group, while the spinal cord and nerve root stresses were greater in the cervical rotation-traction manipulation group than in the oblique pulling manipulation group. The spinal cord and nerve root stresses in the cervical rotation-traction manipulation group were mainly concentrated in the C4/5 and C5/6 segments. Conclusion: The oblique pulling manipulation may be more appropriate for the treatment of cervical spondylotic radiculopathy, while cervical rotation-traction manipulation is more appropriate for the treatment of cervical spondylosis of cervical type. Clinicians should select cervical rotation manipulations for different types of cervical spondylosis according to the patient's symptoms and needs.

Corrigendum to 'Fabrication of a bio-instructive scaffold conferred with a favorable microenvironment allowing for superior implant osseointegration and accelerated in situ vascularized bone regeneration via type H vessel formation' [Bioactive Materials, Volume 9 (March 2022) Page 491-507].

[This corrects the article DOI: 10.1016/j.bioactmat.2021.07.030.].

Fabrication of a bio-instructive scaffold conferred with a favorable microenvironment allowing for superior implant osseointegration and accelerated in situ vascularized bone regeneration via type H vessel formation.

The potential translation of bio-inert polymer scaffolds as bone substitutes is limited by the lack of neovascularization upon implantation and subsequently diminished ingrowth of host bone, most likely resulted from the inability to replicate appropriate endogenous crosstalk between cells. Human umbilical vein endothelial cell-derived decellularized extracellular matrix (HdECM), which contains a collection of angiocrine biomolecules, has recently been demonstrated to mediate endothelial cells(ECs) - osteoprogenitors(OPs) crosstalk. We employed the HdECM to create a PCL (polycaprolactone)/fibrin/HdECM (PFE) hybrid scaffold. We hypothesized PFE scaffold could reconstitute a bio-instructive microenvironment that reintroduces the crosstalk, resulting in vascularized bone regeneration. Following implantation in a rat femoral bone defect, the PFE scaffold demonstrated early vascular infiltration and enhanced bone regeneration by microangiography (µ-AG) and micro-computational tomography (µ-CT). Based on the immunofluorescence studies, PFE mediated the endogenous angiogenesis and osteogenesis with a substantial number of type H vessels and osteoprogenitors. In addition, superior osseointegration was observed by a direct host bone-PCL interface, which was likely attributed to the formation of type H vessels. The bio-instructive microenvironment created by our innovative PFE scaffold made possible superior osseointegration and type H vessel-related bone regeneration. It could become an alternative solution of improving the osseointegration of bone substitutes with the help of induced type H vessels, which could compensate for the inherent biological inertness of synthetic polymers.

Antioxidant-enriched autologous biogel promoted diabetic wound healing by remodeling inherent posttraumatic inflammatory patterning and restoring compromised microenvironment homeostasis.

Successful wound healing depends on the reconstruction of proper tissue homeostasis, particularly in the posttraumatic inflammatory tissue microenvironment. Diabetes jeopardizes tissues' immune homeostasis in cutaneous wounds, causing persistent chronic inflammation and cytokine dysfunction. Previously, we developed an autologous regeneration factor (ARF) technology to extract the cytokine composite from autologous tissue to restore immune homeostasis and promote wound healing. However, treatment efficacy was significantly compromised in diabetic conditions. Therefore, we proposed that a combination of melatonin and ARF, which is beneficial for proper immune homeostasis reconstruction, could be an effective treatment for diabetic wounds. Our research showed that the utilization of melatonin-mediated ARF biogel (AM gel) promoted diabetic wound regeneration at a more rapid healing rate. RNA-Seq analysis showed that AM gel treatment could restore more favorable immune tissue homeostasis with unique inflammatory patterning as a result of the diminished intensity of acute and chronic inflammation. Currently, AM gel could be a novel and promising therapeutic strategy for diabetic wounds in clinical practice through favorable immune homeostatic reconstructions in the tissue microenvironment and proper posttraumatic inflammation patterning.

Mechanical Parameters and Trajectory of Two Chinese Cervical Manipulations Compared by a Motion Capture System.

Objective: To compare the mechanical parameters and trajectory while operating the oblique pulling manipulation and the cervical rotation-traction manipulation. Methods: An experimental research measuring kinematics parameter and recording motion trajectories of two cervical manipulations were carried out. A total of 48 healthy volunteers participated in this study, who were randomly divided into two groups of 24 representing each of the two manipulations. A clinician performed two manipulations in two groups separately. A motion capture system was used to monitor and analyze kinematics parameters during the operation. Results: The two cervical manipulations have similar thrust time, displacement, mean velocity, max velocity, and max acceleration. There were no significant differences in active and passive amplitudes between the two cervical rotation manipulations. The thrust amplitudes of the oblique pulling manipulation and the cervical rotation-traction manipulation were 5.735 ± 3.041° and 2.142 ± 1.742°, respectively. The thrust amplitudes of the oblique pulling manipulation was significantly greater than that of the cervical rotation-traction manipulation (P < 0.001). Conclusion: Compared with the oblique pulling manipulation, the cervical rotation-traction manipulation has a less thrust amplitudes.

An experimental study on the digital precision of internal fixation via the sinus tarsi approach for calcaneal fractures.

OBJECTIVE: To investigate the effectiveness and accuracy of internal fixation of calcaneal fractures with a three-dimensional (3-D) printing navigation module via the sinus approach. METHODS: Eleven lateral lower extremity specimens were used in the experiment and divided into the digital design (DD) group ( n = 11) and the real surgery (RS) group ( n = 11). For the DD group, thin-section computed tomography (CT) scans, virtual fracture modeling, virtual bone plate fixation, sinus occlusal module design, and navigation module design were performed for the cadaver specimens. A 3-D navigation module was printed using a 3-D printer. For the RS group, the sinus approach incision was made, and the navigation module was used to assist the placement of screw fixation and anatomically locked bone plate fixation. Thin-layer CT scans, 3-D reconstructions, and reconstruction of the nail paths were performed in the RS group and 3-D registered with the DD group. 3-D coordinate values for the screw entry and exit points in the RS and DD groups were recorded, and the corresponding offset values of the screw points were calculated. The number of qualified nails at different accuracy levels was counted. The χ2 test was used to compare the data for the DD and RS groups to obtain the accuracy level for both groups when p > 0.05, which is the critical value for experimental accuracy. RESULTS: A total of 11 bone plates were placed and 120 screws were locked. None of them protruded from the inferior articular surface. The screw entry and exit point offsets were 1.71 ± 0.11 mm and 3.10 ± 0.19 mm, respectively. When the accuracy requirement for the entry point was 3.8 mm, there was no statistically significant difference between the two groups ( p > 0.05). Similarly, the accuracy of the exit point of the screw could only reach 6.6 mm. CONCLUSION: Internal fixation of calcaneal fractures via the sinus tarsi approach with an anatomical locking plate based on the 3-D printing navigation module can achieve accurate screw placement and good overall internal fixation.

Anatomical reduction and precise internal fixation of intra-articular fractures of the distal radius with virtual X-ray and 3D printing.

To evaluate and precisely internal fix intra-articular distal radial fracture (IDRF) using the virtual X-ray and three-dimensional (3D) printing technologies. Twenty-one patients with IDRF were recruited, and the data from digital design group (DDG) and real surgery group (RSG) were collected and analyzed. In DDG, the data from thin-slice computed tomography scan, virtual X-ray measurement parameters, including volar tilt, palmar tilt, radius length (D1), ulnar variation (D2), locking plate position parameter (D3) and distance between key nail and joint surface (D4) were collected. The bone was virtually fixed with the locking plate, and the final model of radius with the screw was obtained by 3D printing. In RSG, the locking plate was precisely pre-bended and used in surgery. During the surgery, the key K-wire was accurately placed and the locking plate was adjusted with the aid of the U-shaped navigation arm. The C-arm was used to observe the positions of key K-wires and the locking plate, and the same above-mentioned parameters were measured intra- and post-operatively. The data from RSG and DDG were compared statistically by t test. This approach proved to be successful in all 21 patients, and none of the screws pierced through the wrist joint surface. All the measured parameters, including the volar tilt, palmar tilt, D1-4, in RSG were not significantly different from preoperative DDG data. Virtual X-ray measurement of anatomical reduction parameters and 3D printing can help the anatomical reduction and precise internal fixation by providing quantitative references, preoperatively, intraoperatively and postoperatively.

[REPAIR OF COMPOSITE TISSUE DEFECTS OF DORSAL THUMB INCLUDING INTERPHALANGEAL JOINT BY TRANSPLANTATION OF MODIFIED HALLUX TOE-NAIL COMPOSITE TISSUE FLAP].

OBJECTIVE: To explore a new improved technique and its effectiveness to repair dorsal thumb composite tissue defects including interphalangeal joint by transplantation of modified hallux toe-nail composite tissue flap. METHODS: The hallux toe-nail composite tissue flap carrying distal half hallux proximal phalanx, extensor hallucis longus, and interphalangeal joint capsule were designed and applied to repair the dorsal skin, nails, and interphalangeal joint defect of thumb in 14 cases between January 2007 and June 2013. They were all males, aged from 19 to 52 years (mean, 30 years). The time from injury to hospital was 0.5-2.0 hours (mean, 1.2 hours). The area of the thumb nail and dorsal skin defects ranged from 2.5 cm x 1.5 cm to 5.0 cm x 2.5 cm. The dorsal interphalangeal joint had different degrees of bone defect, with residual bone and joint capsule at the palm side. The length of bone defect ranged from 2.5 to 4.0 cm (mean, 3.4 cm). The hallux nail flap size ranged from 3.0 cm x 2.0 cm to 6.0 cm x 3.0 cm. The donor sites were repaired by skin grafting in 5 cases, and retrograde second dorsal metatarsal artery island flap in 9 cases. RESULTS: After operation, arterial crisis occurred in 1 case and the flap survived after relieving pressure; the other flaps survived, and wounds healed by first intention. Liquefaction necrosis of the skin grafting at donor site occurred in 3 cases, and the other skin grafting and all retrograde second dorsal metatarsal artery island flaps survived. The follow-up ranged from 9 months to 3 years and 6 months (mean, 23 months). The secondary plastic operation was performed in 4 cases at 6 months after operation because of slightly bulky composite tissue flaps. The other composite tissue flaps had good appearance, color, and texture. The growth of the nail was good in 12 cases, and slightly thickened in 2 cases. At last follow-up, X-ray examination showed that bone graft and proximal phalanx of the thumb had good bone healing in 12 cases. Good bone healing was obtained at the donor site. According to the Hand Surgical Branch of Chinese Medical Association standard for thumb and finger reconstruction function, the results were excellent in 12 cases and good in 2 cases, and the excellent and good rate was 100%. No pain at donor site was observed, with normal gait. CONCLUSION: Transplantation of modified hallux toe-nail composite tissue flap to repair dorsal thumb composite tissue defects including interphalangeal joint can effectively improve the appearance and function of the impaired thumb.

[The Chinese osteoporosis-targeted quality of life short questionnaire: design and reliability and validity assessment].

OBJECTIVE: To design a disease-targeted life-of-quality questionnaire for Chinese patients with primary osteoporosis. METHODS: From October 2013 to January 2014, 144 patients out- and inpatients were selected for assessment of their quality of life using the Chinese Osteoporosis-targeted Quality-of-Life short questionnaire (COQOL, 16 items) designed and reformed based on QUALEFFO-41. Statistics analysis was conducted to assess the validity of the COQOL. RESULTS: Statistics analysis showed good test-retest reliability, internal consistency, content validity, construct validity and criterion validity of COQOL. CONCLUSION: COQOL is reliable and valid for evaluating participants with low bone mass in clinical practice.