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The purpose of this study was to quantify the effect of the flexor carpi ulnaris and the extensor carpi ulnaris muscles on distal radioulnar joint stability. The anteroposterior ulnar head translation in relation to the radius was measured sonographically when the forearm was in a neutral resting position and when the hand was actively pressed on to a surface, with and without intentional flexor carpi ulnaris and extensor carpi ulnaris activation, while also being monitored by an electromyogram. Data on 40 healthy participants indicated a mean anteroposterior translation in the distal radioulnar joint of 4.1 mm (SD 1.08) without and 1.2 mm (SD 0.54) with muscle activation. Our results indicate that intentional ulnar forearm muscle activation results in 70% less anteroposterior ulnar head translation and greater distal radioulnar joint stability. Therefore, the flexor carpi ulnaris and extensor carpi ulnaris muscles serve as dynamic stabilizers of the distal radioulnar joint. This finding may be clinically significant since ulnar forearm muscles strengthening may increase distal radioulnar joint stability.

Background: Sufficient and timely spinal cord decompression is a critical surgical objective for neurological recovery in spinal cord injury (SCI). Residual cord compression may be associated with disturbed cerebrospinal fluid pressure (CSFP) dynamics., Objectives: This study aims to assess whether intrathecal CSFP dynamics in SCI following surgical decompression are feasible and safe, and to explore the diagnostic utility., Methods: Prospective cohort study. Bedside lumbar CSFP dynamics and cervical MRI were obtained following surgical decompression in N = 9 with mostly cervical acute-subacute SCI and N = 2 patients with non-traumatic SCI. CSFP measurements included mean CSFP, cardiac-driven CSFP peak-to-valley amplitudes (CSFPp), Valsalva maneuver, and Queckenstedt's test (firm pressure on jugular veins, QT). From QT, proxies for cerebrospinal fluid pulsatility curve were calculated (ie, relative pulse pressure coefficient; RPPC-Q). CSFP metrics were compared to spine-healthy patients. computer tomography (CT)-myelography was done in 3/8 simultaneous to CSFP measurements., Results: Mean age was 45 ± 9 years (range 17-67; 3F), SCI was complete (AIS A, N = 5) or incomplete (AIS B-D, N = 6). No adverse events related to CSFP assessments. CSFP rise during QT was induced in all patients [range 9.6-26.6 mmHg]. However, CSFPp was reduced in 3/11 (0.1-0.3 mmHg), and in 3/11 RPPC-Q was abnormal (0.01-0.05). Valsalva response was reduced in 8/11 (2.6-23.4 mmHg). CSFP dynamics corresponded to CT-myelography., Conclusions: Comprehensive bedside lumbar CSFP dynamics in SCI following decompression are safe, feasible, and can reveal distinct patterns of residual spinal cord compression. Longitudinal studies are required to define critical thresholds of impaired CSFP dynamics that may impact neurological recovery and requiring surgical revisions.

Background . Given individuals with spinal cord injury (SCI) approaching 2 million, viable options for regenerative repair are desperately needed. Human central nervous system stem cells (HuCNS-SC) are self-renewing, multipotent adult stem cells that engraft, migrate, and differentiate in appropriate regions in multiple animal models of injured brain and spinal cord. Preclinical improved SCI locomotor function provided rationale for the first-in-human SCI clinical trial of HuCNS-SC cells. Evidence of feasibility and long-term safety of cell transplantation into damaged human cord is needed to foster translational progression of cellular therapies. Methods . A first-ever, multisite phase I/IIa trial involving surgical transplantation of 20 million HuCNS-SC cells into the thoracic cord in 12 AIS A or B subjects (traumatic, T2-T11 motor-complete, sensory-incomplete), aged 19 to 53 years, demonstrated safety and preliminary efficacy. Six-year follow-up data were collected (sensory thresholds and neuroimaging augmenting clinical assessments). Findings . The study revealed short- and long-term surgical and medical safety (well-tolerated immunosuppression in population susceptible to infections). Preliminary efficacy measures identified 5/12 with reliable sensory improvements. Unfortunately, without thoracic muscles available for manual muscle examination, thoracic motor changes could not be measured. Lower limb motor scores did not change during the study. Cervical cord imaging revealed, no tumor formation or malformation of the lesion area, and secondary supralesional structural changes similar to SCI control subjects. Interpretation . Short- and long-term safety and feasibility support the consideration of cell transplantation for patients with complete and incomplete SCI. This report is an important step to prepare, foster, and maintain the therapeutic development of cell transplantation for human SCI.

The degree of residual stenosis by fresh thrombus after laser recanalization was compared by use of angiography and angioscopy. Fifteen NZW rabbits were used. Occlusive fresh thrombus in rabbit aorta was produced by mechanical deendothelialization and external constrictions simulating clinical situations. Argon laser angioplasty using microlens-tipped optical fiber and/or 2 mm hot-tip probe was done to recanalize thrombosed aorta in 10 animals. Two-mm hybrid probe was used in 5. Percent area stenosis (% AST) was derived by use of the mean radius method obtained by angiography of stenotic segments in two orthogonal views and/or from angioscopy. All 15 totally occluded vessels with fresh thrombus were recanalized. Four minor perforations occurred. Following argon laser angioplasty with the microlens optical fiber, percent stenosis was reduced to 53% in diameter by angiography and 66 in % AST by angioscopy, and to 48% and 55 respectively following hot-tip probe. After laser angioplasty with the hybrid probe, residual stenosis by fresh thrombus was 37% in diameter on angiography and 63 in % AST on angioscopy. Mean percent AST was 62% with angiography and 52% with angioscopy, and there was no correlation between them (r = -0.028). Angioscopy provided cross-sectional topographic views of thrombosed lumen and showed charring and shrinkage of thrombus following laser angioplasty. This study suggests that (1) continuous-wave laser angioplasty using modified optical fibers can recanalize thrombotic vascular occlusion, (2) laser angioplasty by hot-tip probe could evacuate fresh thrombus more than microlens fiber on angioscopy, and (3) angiographic % AST did not correlate with angioscopic % AST.