Purpose

compare the radiological results in sagittal balance correction obtained with pedicle subtraction osteotomy (PSO) versus anterior-posterior osteotomy (APO) by double approach in adults.

Study Design: A prospective observational study including 43 patients who underwent surgery for degenerative lumbar disease.

Objective: The purpose of this study was to know wich were the expectancies about improvement of patients who underwent a degenerative lumbar disease surgery.

Materials and Methods: Patients with a surgical indication for a degenerative lumbar disease, and followed by spine surgery unit of our insitution, were included. During the day before surgery, Health related quality of life mesures were administrated including SF-36, Oswestry Disability Index (ODI) and a questionnaire adapted to know which ones were our patients preoperative expectancies and the grade of unsatisfaction in case they didn’t accomplish those expectancies after surgery.

Results: 43 patients (22 male, 21 female) were included. Age average was 54 years (rang 22–83), average preoperative ODI value was 48,14 (SD 22’4) and average expected value was 13,14 (SD12,1), with an average of improvement of 72’8% (SD 24’8). Diagnose of estenosis with neurological simptoms was the only parameter associated to improvement in front of isolated low back pain (66,0 SD 29’3; 79’6 SD 17’6 p=0’26%). Previous state, gender, age, SF-36 scores were’nt globaly related to expectancies.

‘Pain’ and ‘to seat’ expectancies were worse in females (r= 0’40 p= 0’023). Age was associated to ‘to lift weight’(r=0’337 p= 0’041), ‘to travel’ (r=0’513 p=0’001) and borderline for ‘sexual activity’ (r=0’315 p= 0’061).

Mental SF-36 score was inversely associated to ‘pain intensity’ (r=−0’449 p= 0’013) and ‘sexual activity’ (r=−0’362 p=0’05). Patients included in our study didn’t expect any improvement for subjects as ‘Personal care’, ‘to sleep’ and ‘to lift weight’ (p=0’9 p=0’2 y p=0’7).

In the group fo workers (16 individuals, 47% of sample), the grade of unsatisfaccion in case of not to be able to return to their occupation, was low. This result was independant to age, gender and diagnose.

Conclusions: Preoperative expectancies of patients before underwent the same surgery are differents. To know about it using a Health related quality of life mesure wich gives the same especific weight to all activities of daily life without knowing which ones are more importants for our patients (according to age, gender, diagnose, social estatus..) could be a bias to evaluate results and the grade of satisfaction of them. More studies are necessary to know if the accomplishment of those expectancies affects the final result of surgery.

Background: Control of acute postoperative pain remains a serious problem. Postoperative pain is associated with an increase in thrombotic or respiratory complications. In the other hand the association between surgery, acute postoperative pain and ongoing chronic pain is well defined.

Target: To evaluate the incidence of severe pain after surgery for degenerative lumbar pain, with two analgesic techniques; intravenous analgesia (i.v.) (group 1) and patient controlled analgesia (PCA) (group 2).

Study design: Retrospective study with dates obtains prospectively.

Patient sample: We studied 206 patients operated between january 04 and june 05. Group 1 (intravenous) 80 patients and 126 in group 2 (PCA).

Outcomes mesasures: Percentage of patients with severe pain, number of rescues and complications.

Materials and methods: The type of postoperative analgesia administrated was decided by the anaesthesiologist. To measure pain intensity the VAS was assessed every 6 hours and worst score was used, excluding recovery room. Type of rescue analgesia was the same in all patients and these was recommended in VAS > 3. We evaluate sex, age and comorbidity by ASA. We have defining analgesic ‘failure’ by the overall incidence of pain intensity in two categories: the percentage of patients who experienced moderate-severe pain (VAS > 3) and severe pain (VAS> or = 7). As the pain scores were not normally distributed we not used mean and SD of VAS. The number of rescues and complications were also evaluated.

Results: There was not differences in median age (group 1 50’85 sd 15’4; group 2 52’44 sd 15’4 p=0’47), ASA (group 1 1’89 sd 0’75; group 2 1’90 sd 0’57 p=0’88) or diagnosis between two groups. There were differences in percentages of sexes, group 1 with 40% of women and 62’69% in group 2 (p=0’013). There were not differences in incidence of patients with moderate-severe pain (group 1 15/80; group 2 30/126. p=0’392) neither in incidence of patients with severe pain (group 1 33/80; group 2 51/126. p=0’912). There were not differences in number of rescues (p=0’912) neither in number of complications between groups. Global incidence of VAS > 3 were 40’8 but the incidence of rescues were 25’2%

Conclusions: Our findings suggest that both techniques have similar effectiveness, although the global incidence of severe pain was not optimal (21’8%). It is important to remark the different between incidence of patients with VAS > 3 and number of rescues administrated.

Objective: The purpose of this study was to evaluate the effectiveness of surgical reconstruction of posttraumatic deformity. Posttraumatic kyphosis (PTK) causes pain, neurological deficit, sagittal imbalance, progressive deformity, cosmetic and functional deterioration. Its treatment is cause of controversy and technically demanding. There are few reviews in the literature about the results of its surgical treatment.

Methods: From 1995 to 2002 twenty-one patients suffering from posttraumatic thoracolumbar kyphosis were operated. The average follow-up was 3.9 years (range 6 – 1 years). The average age was 38 years (range 23–62): 13 female and 8 male. All patients complained about vertebral pain, 16 located at the apex of the deformity, 2 patients in the lumbar area and 3 patients referred also pain above the lesion. Three patients had irradiated circumferential pain and 4 patients mild neurological deficit. Two patients showed sexual dysfunction. In one patient only anterior approach with allograft reconstruction and anterior plate fixation was performed. In 17 patients simultaneous or staged approach with posterior release, anterior discectomy and allograft reconstruction and posterior compressed instrumentation was performed. In three patients a posterior closing wedge osteotomy was performed

Results: Postoperative pain decreased from 7.5 to 2.8 (VAS). Functional status: preoperative 42.3 % and postoperative 13.8% (Oswestry score). There was no hardware failure. All cases showed solid fusion without significant loss of correction. The average corrected kyphosis was 27.3°. All patients were satisfied with their cosmetic result. No cavity drainage was performed in 2 patients with syringomielia. 1 of 4 patients with neurological deficit did not improve. Two patients had thoracic neuropathic postoperative pain; one of them needed pain clinic treatment until remission. One case had superficial infection. One patient showed a Chylous leakage.

Discussion: Only few works analyze the results of surgical treatment of PTK. The controvesrsy between anterior-aposterior surgery versus posterior closing wedge osteotomy depens of classification of posttraumatic spinal deformities based on three criteria: the region involved, the neurological status and the presence of any sagittal or frontal plane deformities outsides the local kyphosis

Conclusions: Our results suggest that the double approach with anterior allograft and posterior instrumentation shows clinical and radiological efficacy for sagittal posttraumatic deformity. In spite of surgical risk, there have been few complications with a high rate of patient satisfaction.

Aim: Investigate the influence of various types of allograft (from the tibia, femur, and fibula) through finite element analysis to evaluate the best clinical configuration.

Methods: A non-linear 3D finite element model of a lumbar spine L3–L5 was used as a physiologic model (Noailly, 2003). The model was modified with the insertion of a transpedicular instrumentation (Surgival SA, Spain) and the removal of the L4 body and two adjacent discs. CT scans of a femur, tibia and fibula from the same patient were performed. Fragments of each bone were reconstructed and inserted within the model. Four configurations of allografts were investigated: one femur fragment, one tibial fragment, three fragments of fibula, six fragments of fibula. Four types of loadings were applied: compression (1000N), flexion, extension, and rotation (15Nm). Strain and stresses were calculated in large displacement (MARC, MSC Software).

Results: Von Mises stresses within the internal fixator are well below the Yield stress and the fatigue limit and therefore no fracture of the fixator is foreseen. The use of a fixator to create fusion of the two vertebras makes the lumbar spine much stiffer. The geometry and configuration of the allografts have a large influence on the strain and stresses within the adjacent vertebrae with a reduction of strains and stresses. The use of fragments of fibula gives the most stable configuration. However, this is also the configuration that changes most the maximal principal strains within the vertebrae. Results obtained with the femur or the tibia are very similar between each other. However, due to its ellipsoidal geometry, the allograft in tibia gives more asymmetric deformations than the femur.

Conclusion: Allografts harvested from the femur seems to be more reliable and change least the strain and stress distributions within the lumbar spine compared to allografts from the tibia or fibula.

Aim: Investigate the influence of end-plate preparation in a model of corporectomy to evaluate the best biomechanical configuration.

Methods: A non-linear 3D finite element model of a lumbar spine L3–L5 was used as a physiologic model (Noailly, 2003). The model was modified with the insertion of a transpedicular instrumentation (Surgival SA, Spain) and the removal of the L4 vertebral body and two adjacent discs. A femur allograft was inserted anteriorly. Four configurations were investigated: with allograft supported on the entire end-plate, with allograft supported on the half of cartilage endplate thickness, with allograft supported on the subcondral cortical shell and, finally, with allograft supported on the trabecular bone. Four types of loadings were applied: compression (1000N), flexion, extension, and rotation (15Nm). Strain and stresses were calculated in large displacement (MARC, MSC Software).

Results: Results indicate that the preparation of the end-plates has a minor influence on the strain and stresses within the adjacent vertebrae when rigid transpedicular instrumentation was placed. The use of a fixator to create fusion of the two vertebras makes the lumbar spine much stiffer. The resection of the cartilage and support the allograft in the cortical shell changes most the maximal principal strains in the remaining end-plate, and creates a peak stress in the contact area. On the other hand, complete resection of cartilage and subcondral cortical end-plate is the configuration that changes least the maximal principal strains within the adjacent vertebrae.

Conclusion: Preservation of the cortical end-plate may not offer a significant biomechanical advantage in reconstructing the anterior column when rigid transpedicular instrumentation was used.