Is there a rational basis for post-surgical lifting restrictions? 2. Possible scientific approach

Lifting restrictions postoperatively are quite common but there appears to be little scientific basis for them. Lifting restricitions are inhibitory i n terms of return to work and may be a factor in chronicity. The mean chang es in functional spinal motion unit (FSU) stiffness with in vitro or comput er-simulated discectomies, facetectomies and laminectomies were reviewed fr om the literature. We modified the NIOSH lifting equation to include anothe r multiplier related to stiffness change post surgery. The new recommended lifts were computed for different lifting conditions seen in industry. The reduction of rotational stiffness ranged from 21% to 41% for a discectomy, 1% to 59% for a facetectomy and 4% to 16% for a partial laminectomy. The re commended lifts based on our modified equation were adjusted accordingly. T here is no rational basis for current lifting resctrictions. The risk to th e spine is a function of many other variables as well as weight (i.e., dist ance of weight from body). The adjusted NIOSH guidelines provide a reasonab le way to estimate weight restrictions and accomodations such as lifting ai ds. Such resitrictions should be as liberal as possible so as to facilitate , not prevent, return to work. Patients need more advice regarding lifting activities and clinicians should be more knowledgeable about the working co nditions and constraints of a given workplace to effectively match the solu tion to the patient's condition.