Incidence and treatment of delayed symptoms of CSF leak following lumbar spinal surgery.

PURPOSE: Dural tear (DT) resulting in cerebrospinal fluid (CSF) leak is a common complication of spinal surgery. Most cases of DT are recognised and addressed intraoperatively; however, a small percentage of cases may present at a later stage with delayed symptoms of CSF leak, either due to an unrecognised intraoperative DT or as a result of a de novo delayed DT. Apart from few reports describing delayed symptomatic CSF leaks, most studies tend not to separate intraoperatively recognised DTs from delayed symptomatic CSF leaks. To our knowledge, there are no long-term studies describing specifically the incidence and management of this complication. The aim of this study is to determine the incidence of late presentation of dural tear (LPDT) following lumbar spinal surgery, its treatment, associated complications and clinical outcomes from long-term follow-up in a consecutive series of patients. METHODS: A retrospective review was conducted on 2052 consecutive patients who underwent spinal surgery by two spinal surgeons from 2000 to 2005 and 2007 to 2013 at two institutions. RESULTS: A total of 2052 patient records were reviewed. Seventeen patients (0.83%) were found to have LPDT, unrecognised intraoperatively. Fifteen patients required surgical intervention, one patient was treated with insertion of a subarachnoid drain and only one patient settled with conservative measures. Out of the 15 patients who underwent surgery, two patients required another operation and 2 patients were treated with a subarachnoid drain. At 9 months mean follow-up, there was no significant difference in outcome in cases with LPDT compared to those without. CONCLUSION: A delayed symptomatic presentation of DT unrecognised intraoperatively is a specific complication that needs to be recognised and treated appropriately. A high suspicion and vigilance can help discover and address delayed CSF leaks with no long-term sequelae.

Co-activation of the hamstrings and quadriceps during the lunge exercise.

The anterior lunge exercise is a closed chain kinetic exercise that has been developed to improve the function of the lower limb and to strengthen the hamstrings and quadriceps, simultaneously. In this study, a three-dimensional biomechanical analysis of this exercise was conducted in order to understand the mechanics of this rehabilitation activity. Experimental conditions were recorded using an active optoelectronic kinematic data capture system (OPTOTRAK), two force plates (AMTI) and electromyography (EMG). Data were collected from healthy male subjects while performing several lunges. When the distance between the toe of the rear leg and the heel of the front leg (lunging distance) was maximum, a large net flexion moment was predicted in the front leg in the extented position. This moment was reversed to a large net extension moment in the flexed position. A large increase in the net extension moment in the rear leg was also predicted as the front knee was bent from 5 degrees to 90 degrees of flexion. These data suggest that quadriceps and hamstring muscles co-contraction occur during a maximum lunge in the front leg when it is in the flexed position.