Grip force control during object manipulation in cervical myelopathy.

STUDY DESIGN: Cross-sectional research. OBJECTIVES: To objectively evaluate grip force (GF) control while holding a freely movable object in individuals with cervical myelopathy (CM). SETTING: Harunaso Hospital, Takasaki, Japan. METHODS: We studied 52 hands from 26 individuals with CM. Participants performed a grip-and-lift task by pulp pinch using the thumb and index finger before surgery. We monitored individual finger GF (N) during the first 3 s while lifting and holding an object. Correlations between the GF and other clinical tests were evaluated. A multiple stepwise regression analysis was used to examine the contribution of the GF to the severity of clinical symptoms. RESULTS: Thumb GF was negatively correlated with the 10-s test (rs = -0.32), and index finger GF was positively correlated with its cutaneous pressure threshold (rs = 0.34). Multiple regression for the severity of upper extremity symptoms revealed that the model including the GF had a larger adjusted R2 and a lower AIC value than that of conventionally used clinical tests. CONCLUSIONS: These results suggested that the assessment of individual finger GF control could provide an indicator of the clinical severity of upper extremity in individuals with CM.

Changes in reaching skill in patients with cervical spondylosis after cervical decompression surgery.

[Purpose] The aim of this study was to evaluate the changes in reaching function during a reaching task in cervical spondylosis (CS) patients before and after surgery. [Participants and Methods] Nine patients participated in the study. Wrist acceleration peaks were monitored pre- and postoperatively using a tri-axial accelerometer, and the Japanese Orthopedic Association (JOA) score was recorded preoperatively. Additional upper extremity function tests were performed pre- and postoperatively. Multiple stepwise regression analysis was used to investigate the contribution of wrist acceleration peak to the severity of clinical symptoms. Moreover, we compared the acceleration peaks produced during the reaching task before and after surgery. [Results] Multiple regression analysis showed that wrist acceleration peak, grip strength and pinch strength were associated with the upper extremity function of the JOA score, explaining 61.0% of the variance. There was a significant improvement in x-axis acceleration peak after surgery. [Conclusion] Our results suggested that quantitative assessments of reaching function are useful to objectively evaluate the changes in reaching function in patients undergoing cervical decompression surgery.