Kinematic analysis of chewing and swallowing function after cervical spine surgery.

PURPOSE: Although movement of the hyoid bone is different for masticatory swallowing and liquid swallowing in normal subjects, it has not been studied after cervical spine surgery. Therefore, we analyzed the swallowing dynamics of masticatory swallowing in anterior cervical spine disease surgery using foods that require chewing close to actual meals. METHODS: A day before and one week after the surgery, a videofluoroscopic swallow study (VFSS) was performed, and the distance of hyoid bone movement in the anterior and superior directions, amount of opening of the upper esophageal sphincter (UES), time of passage through the pharynx, number of swallows, and amount of pharyngeal residual were measured on the VFSS images during a masticatory swallow of corn flakes. The swallowing function was evaluated by DSS (dysphagia severity scale) and FOIS (functional oral intake scale). Imaging software was used for the measurements. RESULTS: Postoperative hyoid movement during masticatory swallowing was not significantly different for anterior movement but significantly limited in upward movement (p = 0.002); UES opening volume was significantly decreased (p < 0.001), and bolus residue was significantly worse (p < 0.001), compared to preoperative. The pharyngeal transit time was not significantly different; the number of swallows increased (p < 0.001), along with DSS (p < 0.001) and FOIS (p < 0.001), with significant differences before and after surgery, indicating worsened swallowing function. CONCLUSIONS: Swallowing function worsened in masticatory swallowing after surgery for cervical spine disease, mainly due to the restriction of upward movement of the hyoid bone and the resulting increase in pharyngeal residuals after swallowing.

The Safety of Oral Rehydration Solution Jelly for Water and Electrolyte Intake in Patients with Dysphagia.

Purpose: Oral rehydration solutions (ORSs) are effective in replacing fluids and electrolytes and are widely used. OS-1 Jelly (Otsuka Pharmaceutical Factory, Tokushima, Japan) is a jelly drink corresponding to code 2-1 of the 2021 Japanese Dysphagia Diet. Although jelly drinks are less likely to be aspirated than liquids, their physical properties vary depending on the product. Therefore, the severity of dysphagia may affect intake status. This study aimed to investigate the association between the intake status of ORS jelly and swallowing function. Patients and Methods: Thirty-six patients with dysphagia who required videoendoscopic swallowing evaluation at our university hospital were enrolled. Videoendoscopic swallowing evaluation was performed, and each participant swallowed 5 mL of OS-1 Jelly or thickened water modified to International Dysphagia Diet Standardization Initiative (IDDSI) level 2 three times. Statistical analysis was performed to determine the difference in the number of swallows, time until the swallowing reflex, position for inducing the swallowing reflex, presence of pharyngeal residue, penetration, or aspiration between ORS jelly and thickened water. Results: The time until the swallowing reflex was induced and the position of the swallowing reflex triggered were significantly earlier for ORS jelly (p=0.012, p=0.001). The incidence of pharyngeal residue was significantly lower with ORS jelly (p=0.002). The Penetration-Aspiration Scale score was similar for both samples (p=0.062), and no aspiration was observed in either sample. Conclusion: Patients with dysphagia who can swallow thickened water modified to IDDSI level 2 can consume ORS jelly. ORS jelly, which requires no thickening and can be easily and safely consumed, is effective for water and electrolyte intake in patients with dysphagia.

Analysis of swallowing function after anterior/posterior surgery for cervical degenerative disorders and factors related to the occurrence of postoperative dysphagia.

BACKGROUND CONTEXT: Dysphagia is one of the postoperative complications of cervical degenerative disorders. However, few studies have evaluated the pre- and postoperative swallowing function in detail. PURPOSE: To analyze pre- and postoperative swallowing dynamics kinetically and investigate factors associated with postoperative dysphagia in patients with cervical degenerative disorders. STUDY DESIGN: Retrospective review of prospectively collected data. PATIENT SAMPLE: A total of 41 consecutive patients who underwent an anterior approach (anterior cervical discectomy/corpectomy and fusion (ACDF, ACCF), hybrid surgery (ACDF+ACCF) and total disc replacement) and 44 consecutive patients who underwent a posterior approach (laminoplasty and laminoplasty/laminectomy with fusion). OUTCOME MEASURES: We compared the pre- and postoperative functional oral intake scale (FOIS), dysphagia severity scale (DSS), esophageal dysphagia, anterior/superior hyoid movement, upper esophageal sphincter (UES) opening, pharyngeal transit time, bolus residue scale (BRS), and the number of swallows. METHODS: Videofluoroscopy was performed on the day before surgery and within two weeks after surgery. Data related to age, gender, disease, surgical procedure, surgical site, operative time, and blood loss were collected from the medical records. Pre- and postoperative data were compared for each item in the anterior and posterior approaches. The odds ratio of dysphagia after an anterior approach was also calculated. RESULTS: In the anterior approach, DSS, FOIS, the anterior and superior hyoid movements, maximum UES opening, BRS, and number of swallows worsened postoperatively (p<.05, respectively). In the posterior approach, DSS, FOIS, the anterior hyoid movement, and BRS worsened postoperatively (p<.05, respectively). The factors associated with dysphagia were a proximal surgical site above C3 (OR: 14.40, CI: 2.84-73.02), blood loss >100 mL (OR: 9.60, CI: 2.06-44.74), an operative time >200 minutes (OR: 8.18, CI: 1.51-44.49), and an extensive surgical field of more than three intervertebral levels (OR: 6.72, CI: 1.50-30.07). The decline in swallowing function after the posterior approach was related to aging (p=.045). CONCLUSIONS: Each approach may decrease swallowing function, especially because of the limitation on the anterior hyoid movement. Dysphagia after anterior approaches was associated with the operative site, operative time, and blood loss.