ABSTRACT
BACKGROUND AND OBJECTIVE: Preincisional and postoperative transcutaneous electrical nerve stimulation (TENS) administration reduces postoperative opioid demand in abdominal surgery. Aim of this study was to find out whether a comparable effect of TENS applies in major spinal surgery. METHODS: Thirty-eight patients of both sex scheduled for lumbar interbody fusion were enrolled and divided randomly into 3 groups. Group A received TENS preincisional and postoperative, group B received this treatment postoperative only, and group C was the sham controlled. The postoperative demand on piritramid to achieve a visual anlog scale pain score <3 was delivered either by nurse or by a patient-controlled analgesia pump, when the patients were alert. The setting of the patient-controlled analgesia pump, bolus of piritramid 2 mg intravenously (IV), lockout time of 20 minutes, and maximum dose of piritramid 15 mg within 4 hours, the coanalgesic therapy diclofenac 75 mg IV, and the rescue medication metamizol 1 g IV was identical for all patients. The total amount of piritramid administered over the first 24 hours after surgery and an optional rescue medication were recorded. RESULTS: All groups were compared by pairs. The postoperative demand on piritramid differed significantly A versus B (P<0.05), A versus C (P<0.05), and B versus C (P<0.05). Neither sex, body mass index, current, duration, and type of operation nor the occurrence of hypotensive phases showed any significant association with postoperative piritramid demand. The necessity of rescue medication was significantly higher in group C than in group A. CONCLUSIONS: Postoperative TENS as well as the combination of preincisional and postoperative TENS therapy reduce the postoperative demand of piritramid in major spinal surgery in a safe and simple way free of systemic side effects.
Subject(s)
Analgesics, Opioid/administration & dosage , Pain, Postoperative/therapy , Postoperative Care/methods , Preoperative Care/methods , Spine/surgery , Transcutaneous Electric Nerve Stimulation/methods , Adult , Aged , Aged, 80 and over , Analgesia, Patient-Controlled , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Diclofenac/administration & dosage , Dipyrone/administration & dosage , Drug Administration Schedule , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Pain Measurement/methods , Pirinitramide/administration & dosage , Prospective Studies , Single-Blind MethodABSTRACT
The definition of spinal instability is still controversial. For this reason, it is essential to better understand the difference in biomechanical behaviour between healthy and degenerated human spinal segments in vivo. A novel computer-assisted instrument was developed with the objective to characterize the biomechanical parameters of the spinal segment. Investigation of the viscoelastic properties as well as the dynamic spinal stiffness was performed during a minimally invasive procedure (microdiscectomy) on five patients. Measurements were performed intraoperatively and the protocol consisted of a dynamic part, where spinal stiffness was computed, and a static part, where force relaxation of the segment under constant elongation was studied. The repeatability of the measurement procedure was demonstrated with five replicated tests. The spinal segment tissues were found to have viscoelastic properties. Preliminary tests confirmed a decrease in stiffness after decompression surgery. Patients with non-relaxed muscles showed higher stiffness and relaxation rate compared to patients with relaxed muscles, which can be explained by the contraction and relaxation reflex of muscles under fast and then static elongation. The results show the usefulness of the biomechanical characterization of the human lumbar spinal segment to improve the understanding of the contribution of individual anatomical structures to spinal stability.
Subject(s)
Lumbar Vertebrae/physiopathology , Lumbar Vertebrae/surgery , Lumbosacral Region/physiopathology , Spine/physiopathology , Spine/surgery , Biomechanical Phenomena , Elasticity , Equipment Design , Humans , Lumbosacral Region/surgery , Minimally Invasive Surgical Procedures/instrumentation , Orthopedic Procedures/instrumentation , Reproducibility of Results , Spinal Fusion/instrumentation , Stress, Mechanical , ViscosityABSTRACT
OBJECTIVE: To test a new tiny-tipped intraoperative diagnostic tool that was designed to provide the surgeon with reliable stiffness data on the motion segment during microdiscectomy. A decrease in stiffness after nuclectomy and a measurable influence of muscle tension were assumed. If the influence of muscle tension on the motion segment could at least be ruled out, there should be no difference with regard to stiffness between women and men. If these criteria are met, this new intraoperative diagnostic tool could be used in further studies for objective decision-making regarding additional stabilization systems after microdiscectomy. METHODS: After evaluation of the influence of muscle relaxation during in vivo measurements with a spinal spreader between the spinous processes, 21 motion segments were investigated in 21 patients. Using a standardized protocol, including quantified muscle relaxation, spinal stiffness was measured before laminotomy and after nuclectomy. RESULTS: The decrease in stiffness after microdiscectomy was highly significant. There were no statistically significant differences between men and women. The average stiffness value before discectomy was 33.7 N/mm, and it decreased to 25.6 N/mm after discectomy. The average decrease in stiffness was 8.1 N/mm (24%). CONCLUSION: In the moderately degenerated spine, stiffness decreases significantly after microdiscectomy. Control for muscle relaxation is essential when measuring in vivo spinal stiffness. The new spinal spreader was found to provide reliable data. This spreader could be used in further studies for objective decision-making about additional stabilization systems after microdiscectomy.
