Jau-Ching Wu, Wen-Cheng Huang, Ming-Chao Huang, Yun-An Tsai, Yu-Chun Chen, Yang-Hsin Shih and Henrich Cheng
In this study, the authors evaluated the efficacy of a new surgical strategy for reconnecting the injured brachial plexus with the spinal cord using fibrin glue containing acidic fibroblast growth factor as an adhesive and neurotrophic agent.
Eighteen patients with preganglionic brachial plexus injuries, each with varying degrees of upper limb dysfunction, underwent cervical laminectomy with or without sural nerve grafting. The treatment of each avulsed root varied according to the severity of the injury. Some patients also underwent a second-stage operation involving supraclavicular brachial plexus exploration for reconnection with the corresponding segment of cervical spinal cord at the trunk level. Muscle strength was graded both pre- and postoperatively with the British Medical Research Council scale, and the results were analyzed with the Friedman and Wilcoxon signed-rank tests.
Muscle strength improvements were observed in 16 of the 18 patients after 24 months of follow-up. Significant improvements in mean muscle strength were observed in patients from all repair method groups at 12 and 24 months postoperatively (p < 0.05). Statistical significance was not reached in the groups with insufficient numbers of cases.
The authors' new surgical strategy yielded clinical improvement in muscle strength after preganglionic brachial plexus injury, such that nerve regeneration may have taken place. Reconnection of the brachial plexus to the cervical spinal cord is possible. Functional motor recovery, observed through increases in Medical Research Council–rated muscle strength in the affected arm, is likewise possible.
Chin-Chu Ko, Hsiao-Wen Tsai, Wen-Cheng Huang, Jau-Ching Wu, Yu-Chun Chen, Yang-Hsin Shih, Hung-Chieh Chen, Ching-Lan Wu and Henrich Cheng
Dynamic stabilization systems are used to stabilize degenerative lumbar spondylosis. Loosening of the pedicle screws in such nonfusion implants is predictable. This retrospective study evaluated the incidence of screw loosening and its effect on clinical outcomes.
Charts, radiographic films, and medical records of 71 consecutive patients who underwent decompression using Dynesys dynamic stabilization for 1- or 2-level lumbar spondylosis were reviewed. Radiographic films were evaluated and compared to detect screw loosening. A visual analog scale (VAS) for back pain and the Oswestry Disability Index (ODI) were used for measuring clinical outcome. Statistical analysis was conducted using the chisquare test and Student t-test.
The 71 patients in the study sample had a mean age of 59.2 ± 11.65 years (range 23–80 years), with slight female predominance (39 women, 32 men). The mean follow-up duration was 16.6 months (range 8–29 months). There were loose screws in 14 of 71 patients (19.7%), for a rate of 4.6% per screw (17 of 368 screws). Most screw loosening occurred in patients ≥ 55 years old (13 of 14 patients) although age and sex had no effect on screw loosening (p = 0.233 and 0.109, respectively). Both the loose screw and solid screw groups experienced significant improvement after the surgery in VAS and ODI scores. On the VAS, scores improved from 5.9 ± 2.99 to 2.1 ± 2.14 in the loose screw group (p = 0.003), and from 5.7 ± 3.45 to 2.9 ± 2.68 in the solid screw group (p < 0.001). For the ODI scale, scores improved from 43.5 ± 16.78% to 28.0 ± 18.18% (p = 0.006) in the loose screw group, and from 52.1 ± 20.92% to 24.6 ± 19.78% (p < 0.001) in the solid screw group. There were no significant differences between the 2 groups (p = 0.334 for VAS, p = 0.567 for ODI).
The preliminary study of this pedicle-based dynamic stabilization device for 1- and 2-level lumbar spondylosis shows radiographic evidence of screw loosening in 19.7% of patients and 4.6% of screws. Nonetheless, the loosening of screws has no adverse effect on clinical improvement.
Tsung-Hsi Tu, Jau-Ching Wu, Wen-Cheng Huang, Wan-Yuo Guo, Ching-Lan Wu, Yang-Hsin Shih and Henrich Cheng
Heterotopic ossification (HO) after cervical total disc replacement (TDR) has been reported to impede artificial disc motion. In all previously reported cases of HO, assessment was based on plain radiographs. The authors hypothesized that CT scan is a more sensitive and accurate detector. The aims of this study were to assess the actual incidence of HO and its effect on outcome in a cohort of patients undergoing cervical TDR with the Bryan disc and to compare HO detection by means of plain radiographs and CT.
The authors retrospectively assessed data from medical records, radiological studies, and clinical evaluations of patients who underwent 1- or 2-level cervical TDR with the Bryan disc and were followed up for more than 12 months. The presence and grading of HO according to the McAfee classification were assessed by CT scan, and these findings were compared with findings on plain radiographs. Thirty-six patients (mean age 46.61 ± 7.24 years; range 29–60 years; 21 men and 15 women) who underwent Bryan TDR at 52 levels were included in the study. The mean duration of CT follow-up was 19.03 ± 4.64 months; the mean duration of clinical follow-up was 26.78 ± 7.20 months.
On the basis of CT, HO was identified in 18 (50%) of 36 patients and 25 (48.1%) of 52 levels treated. Grade 1 HO was present in 9 of the levels treated (17.3%), Grade 2 in 13 levels (25.0%), Grade 3 in 2 levels (3.8%), and Grade 4 in 1 level (1.9%). Nineteen (76%) of the 25 affected levels were in patients who had undergone 2-level TDR. There was no significant association with patient sex or disc pathology. There was a tendency for HO development among older patients, but this finding was not statistically significant (mean age 48.8 ± 6.8 in patients with HO vs 44.4 ± 7.2 in those without HO, p = 0.065). Although HO was found in 25 levels, 96.2% of the treated levels (50 of 52) had segmental range of motion on dynamic (flexion and extension) radiographs. The concordance between HO grading by CT and radiography was high, with an intraclass correlation coefficient of 0.822 (lower limit of 95% CI: 0.710, p < 0.001). Patients who had HO had the same clinical success rate as those who did not (94.4% vs 94.4%, p = 1.00). The visual analog scale scores for neck and arm pain were significantly improved in both the HO and the non-HO group.
The rate of HO detected by CT scan in this cohort of patients undergoing cervical TDR with a Bryan disc was 48.1% per level treated and 50% per patient with minimal limitation of segmental motion (96.2% of levels remained mobile), but plain radiograph is an acceptable detection tool. Two-level surgery has a higher risk of HO, although development of HO does not affect clinical outcome.