Biomedical subjects

Rolando M Puno

Publications and source records attributed to Rolando M Puno.

6 recordsLinked to original sources

PubMed2006

Posterolateral lumbar spine fusion with INFUSE bone graft.

BACKGROUND CONTEXT: INFUSE has been proven effective in conjunction with threaded cages and bone dowels for single-level anterior lumbar interbody fusion (ALIF). The published experience with posterolateral fusion, although encouraging, utilizes a significantly higher dose and concentration of recombinant human bone morphogenic protein-2 (rhBMP-2) and a different carrier than the commercially available INFUSE. PURPOSE: To present an assessment of fusion rate for posterolateral spine fusion with INFUSE Bone Graft. STUDY DESIGN/SETTING: Retrospective review of patients treated using INFUSE in posterolateral spine fusion in a single institution. PATIENT SAMPLE: 91 patients with minimum 2-year follow-up who underwent posterolateral spine fusion using INFUSE as an iliac crest bone graft (ICBG) substitute. OUTCOME MEASURES: Fusion rate based on fine-cut computed tomographic (CT) scans with sagittal and coronal reconstructions. METHODS: Fusion was performed using one large INFUSE kit (12 mg rhBMP-2, 1.5 mg/mL), which was prepared according to the manufacturer's instructions. The INFUSE sponge was wrapped around the local bone or graft extender and placed over the decorticated surfaces in the lateral gutters. Postoperative CT scans with reconstructions were reviewed by two independent orthopedic spine surgeons. CT scans of a comparison group of 35 patients who underwent primary single-level posterolateral fusion with ICBG were also reviewed. RESULTS: The overall group had a mean 4.38 CT fusion grade and a 6.6% nonunion rate. Primary one-level fusion cases (n=48) had a mean 4.42 fusion grade a 4.2% nonunion rate. Primary multilevel fusions (n=27) had a mean 4.65 CT grade and no nonunions detected. Assessment of the 35 primary one-level ICBG control cases demonstrated a mean CT grade of 4.35 and a nonunion rate of 11.4%. In the 16 cases of revision for prior nonunion, mean CT grade was 3.81 and 4 subjects had nonunions. Additional subgroup analysis showed that smokers (n=14) had a mean 4.32 CT grade with no nonunions. Men had a mean 4.04 CT grade and an 11.1% nonunion rate compared with a mean 4.61 CT grade and 3.6% nonunion rate in women. This difference was statistically significant (p=.036). No significant differences in fusion rate were observed based upon the specific graft extender used (p=.200). CONCLUSIONS: Posterolateral spine fusion involves a more difficult healing environment with a limited surface for healing, a gap between transverse processes and the milieu of distractive forces. Historically, only ICBG has been able to overcome these challenges and reliably generate a successful posterolateral lumbar spine fusion. In contrast to prior studies, clinically available INFUSE delivers only 12 mg rhBMP-2 at a concentration of 1.5 mg/mL. Despite the lower dose and concentration of rhBMP-2, this study suggests that fusion success with INFUSE is equivalent to ICBG for posterolateral spine fusion. As with ICBG, development of solid fusion or nonunion is a multifactorial process. The use of INFUSE is not a substitute for proper surgical technique or optimization of patient-related risk factors. Additional studies are needed to determine the incremental benefit of a greater rhBMP-2 dose or use of alternative carriers for posterolateral fusion. Finally, correlation between radiographic findings and clinical outcomes, and a cost-benefit analysis are needed. Despite these issues, this study presents compelling evidence that commercially available INFUSE is an effective ICBG substitute for one- and two-level posterolateral instrumented spine fusion.

Adult↗

PubMed2006

Lumbar degenerative classification study.

The purpose of this study was to develop and validate a classification of indications for fusion in lumbar degenerative disease. Nineteen spine surgeons reviewed a series of 32 case histories and selected the indication for fusion based on an outlined classification system. To determine the degree of interrater variability, K coefficients were calculated (K for all 32 cases, 0.63). Results from this study show the significant difficulty in classifying the indication for fusion in lumbar degenerative disease. The level of the 19 surgeons' agreement regarding surgical indication was only moderate, despite a study design that eliminated controversial issues of patient and procedure selection. To a significant extent, the difficulty in classifying indication for fusion underlines the importance of the process. If we cannot agree on why a specific patient is selected for fusion, it is then impossible to accurately compare outcomes for a given disease process or surgical technique. For this reason, an ongoing effort to refine nomenclature and classification is necessary.

Adult↗

PubMed2005

Initial fusion rates with recombinant human bone morphogenetic protein-2/compression resistant matrix and a hydroxyapatite and tricalcium phosphate/collagen carrier in posterolateral spinal fusion.

STUDY DESIGN: Prospective, randomized, unblinded study of iliac crest bone graft (ICBG) versus recombinant human bone morphogenetic protein-2/compression resistant matrix (rhBMP-2/CRM)in a posterolateral instrumented fusion procedure. OBJECTIVES: Document initial radiographic characteristics, based on computed tomography, with rhBMP-2/CRM for posterolateral fusion at 6 and 12-month intervals. SUMMARY OF BACKGROUND DATA: As the acceptance of INFUSE bone graft as an ICBG replacement becomes more widespread, surgeons have begun to study applications for rhBMP-2 in posterior spinal fusion. Preclinical studies have examined variables including carrier composition, rhBMP-2 concentration, and rhBMP-2 dose. Pilot studies have been performed with encouraging initial results. METHODS: Patients with single level lumbar degenerative disease were enrolled in a randomized study of ICBG versus rhBMP-2/CRM in a posterolateral instrumented fusion procedure. Computed tomography scans at 6 and 12 months were graded as demonstrating no fusion (grade 1), partial or limited unilateral fusion (grade 2), partial or limited bilateral fusion (grade 3), solid unilateral fusion (grade 4), or solid bilateral fusion (grade 5). RESULTS: At our institution, 74 patients (38 rhBMP-2/CRM, 36 ICBG) reached minimum 1-year follow-up and were included in this analysis. Mean fusion grade (scale1-5) at 6 months after surgery was 4.35 in the rhBMP-2/CRM group versus 3.09 in the ICBG group (P < 0.0001). At 1 year after surgery mean fusion grade was 4.62 in the rhBMP-2/CRM group versus 3.77 in the ICBG group (P < 0.0023). CONCLUSIONS: These early results are encouraging and suggest a more rapid incorporation and development of the fusion mass with rhBMP-2/CRM than iliac crest autograft in a single level posterior instrumented fusion.

Adult↗

PubMed2005

Platelet gel (AGF) fails to increase fusion rates in instrumented posterolateral fusions.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To determine the effect on fusion of adding platelet gel to autologous iliac crest graft. SUMMARY OF BACKGROUND DATA: Platelet gel is an osteoinductive material prepared by ultra-concentration of platelets and contains multiple growth factors. Proprietary commercial methods are available for harvesting autologous platelet gel concentrates for use as graft supplement in spine fusions. METHODS: We reviewed 76 consecutive patients who underwent instrumented posterolateral lumbar fusion with autologous iliac crest bone graft mixed with autologous growth factor (AGF). A control group was randomly selected from patients who underwent instrumented posterolateral lumbar fusion with autologous bone graft alone. The groups were matched for age, sex, smoking history, and number of levels fused. Demographic, surgical, and clinical data were collected from medical records. Diagnosis of nonunion was based on exploration during revision surgery or evidence of nonunion on computerized tomography. The Fisher exact test was used to compare fusion rates. RESULTS: In both groups, mean age was 50 years, and 24% were smokers. The nonunion rate was 25% in the AGF group and 17% in the control group. This difference was not statistically significant (P = 0.18). CONCLUSIONS: Platelet gel preparation requires blood draws from the patient. This procedure adds to the risk and cost of surgery. The technique for AGF harvest evaluated in this study provides the highest concentration of platelets among the commercially available methods. Despite this, we showed that platelet gel failed to enhance fusion rate when added to autograft in patients undergoing instrumented posterolateral spinal fusion. The authors do not recommend the use of platelet gel to supplement autologous bone graft during instrumented posterolateral spinal fusion.

Adult↗

PubMed2003

Treatment recommendations for idiopathic scoliosis: an assessment of the Lenke classification.

OBJECTIVE: To determine the usefulness of the treatment recommendation criteria based on the Lenke classification for treatment of idiopathic scoliosis. DESIGN A retrospective radiographic review of 183 patients who underwent anterior and/or posterior fusion for the treatment of idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Recent studies have proven that the Lenke system is relatively efficient and consistent in classifying scoliosis curves. However, the recommendations regarding fusion level have yet to be established as reliable. MATERIALS AND METHODS: One hundred eighty-three patients with idiopathic scoliosis and with a minimum follow-up period of 24 months were included in the study and classified according to the Lenke system. Among these patients, 135 patients were treated with fusion and instrumentation in accordance with the Lenke classification system and are described as Group I. The 48 patients whose treatments were not based on the Lenke system constitute Group II. These two groups were compared in regard to the correction of the Cobb angle and the trunk shift after surgery in order to establish the effectiveness and reliability of the treatment recommendations based on the Lenke classification system. RESULTS: Type 1 primary thoracic curve: there was no difference between the results from the group with selective thoracic fusion (Group I) and from the group with both thoracic and lumbar curves fused (Group II). Type 2 double thoracic scoliosis: the correction of the upper thoracic curve, the first thoracic vertebral tilt, and left shoulder elevation were better in the group with both thoracic curves fused (Group I) than in the group with midthoracic fusion (Group II). Type 3 double major scoliosis: the lumbar curve correction was better in the group with both thoracic and lumbar curves fused (Group I) than in the group with selective thoracic fusion (Group II), and decompensation occurred more frequently in Group II. Type 4 triple major scoliosis: because there were only two patients with this type of curve, no analysis was completed. Type 5 thoracolumbar or lumbar curve: there was no difference between the results from the group with selective thoracolumbar or lumbar fusion (Group I) and the group with thoracic and lumbar curves fused (Group II). Type 6 double major scoliosis with larger lumbar curve: the thoracic curve correction was better in the group with both curves fused (Group I) than in the group with only the lumbar curve fused (Group II). CONCLUSION: Better radiologic results were achieved through the use of the Lenke classification system for the selection of fusion levels by avoiding unnecessary fusion of the nonstructural lumbar or thoracic spine as well as avoiding undercorrection of the structural secondary curves.

Adolescent↗

PubMed2003

Perioperative complications of posterior lumbar decompression and arthrodesis in older adults.

BACKGROUND: Lumbar arthrodesis is commonly done in elderly patients to treat degenerative spine problems. These patients may be at increased risk for complications because of their age and associated medical conditions. In this study, we examined the rates of perioperative complications associated with posterior lumbar decompression and arthrodesis in patients sixty-five years of age or older. METHODS: We reviewed the hospital records of ninety-eight patients who were sixty-five years of age or older when they had a posterior decompression and lumbar arthrodesis with instrumentation, between 1993 and 1995, to treat degenerative disease of the spine. The average age was seventy-two years (range, sixty-five to eighty-four years). RESULTS: Perioperative complications occurred in seventy-eight patients. Twenty-one patients had at least one major complication, and sixty-nine had at least one minor complication. Forty-nine patients had more than one complication. The most common major complication was wound infection (prevalence, 10%), and the most common minor complication was urinary tract infection (prevalence, 34%). The complication rate increased with older age, increased blood loss, longer operative time, and the number of levels of the arthrodesis. CONCLUSIONS: Surgeons should be vigilant about perioperative complications in elderly patients treated with multi-level lumbar decompression and arthrodesis with instrumentation. Elderly patients should be made aware that they are at increased risk for surgical complications because of their age. Attention should be paid to controlling blood loss and limiting operative time.

Aged↗