Patient description: The patient is a 41-year-old man and a known case of Acromegaly who underwent transsphenoidal surgery 4 months ago. He came to the clinic for the follow up lab studies after his primary resection surgery. His lab study shows the IGF-1 level of 4.5 ULN adjusted by sex and age. His random GH level is 4 ug/L. The recent brain MRI confirmed the residual pituitary tumor. His past medical history is only significant for acromegaly due to pituitary adenoma and the recent surgery. After his surgery he takes only vitamin D and multivitamins.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Degenerative Disc Disease Spinal Stenosis Spondylolisthesis The patient can be included in the study if all of the following are met; 1. is at least 18 years of age and skeletally mature 2. must have symptomatic spinal stenosis and/or spondylolisthesis or degenerative disc disease (DDD) at one or two adjacent levels from L2-S1 requiring a fusion 3. must have completed a minimum of three months of unsuccessful conservative, non-operative care 4. must have discogenic back pain with or without leg pain 5. DDD must be confirmed by MRI or CT scans followed by discography (if necessary) 6. must score at least 40 points on the Oswestry Disability Index 7. must score at least a 4 on a 10 cm Visual Analog Scale for back pain 8. must be able to comply with the protocol"s follow-up schedule 9. must understand and sign the informed consent document  The patient must not exhibit any of the following criteria; 1. symptomatic at more than two levels 2. previous fusion surgery at any lumbar level with or without instrumentation (prior discectomy, laminotomy, laminectomy or nucleolysis at the operative (involved) level > 6 months is permitted) 3. more than 50% spondylolisthesis 4. lumbar scoliosis greater than 11 degrees 5. osteoporosis*, osteopenia, osteomalacia, Paget"s disease or metabolic bone disease. 6. spinal tumors 7. active arachnoiditis Pioneer Surgical Technology Confidential nanOss Bioactive Post Marketing Clinical Study: March 11, 2010 Page 8 8. fractures of the epiphyseal plate or fractures for which stabilization of the fracture is not possible. 9. Impaired calcium metabolism 10. active infection or surgical site infection 11. rheumatoid arthritis or other autoimmune disease 12. chronic steroid use (used steroids for one month within the last 6 months) or any medical condition that requires treatment with drugs known to interfere with bone healing 13. systemic disease such as AIDS, HIV, hepatitis (active), tuberculosis 14. morbid obesity defined as body mass index (BMI) >40 or a weight more than 100 lbs over ideal body weight 15. smokers unless the patient agrees to quit at least 2 weeks prior to and for the duration of the study, confirmed by a carboxyhemoglobin test prior to surgery 16. psychosocial disorders that would preclude accurate evaluation or has a history of substance abuse 17. active malignancy except non-melanoma skin cancer; history of any invasive malignancy unless treated and in remission for at least five years 18. documented allergies to porcine collagen or titanium 19. pregnancy, or interested in becoming pregnant in the next four years 20. participation in another investigational study within 30 days *Osteoporosis will be assessed at the time of the preoperative evaluation based on the patient"s history, physical examination and review of the radiographic evaluations. All patients at risk for osteoporosis must obtain a DEXA scan of the spine and hip to determine if the patient has severe osteoporosis. The definition of a patient at risk used by the National Osteoporosis Foundation includes the following: i. Premature menopause (< 45 years) ii. Prolonged amenorrhea (> one year) iii. Maternal history of hip fracture iv. Primary hyperparathyroidism or hyperthyroidism v. Chronic renal failure vi. Previous fragility fractures, particularly of the hip, spine or wrist vii. Patients who have ever taken corticosteroids in doses >7.5 mg/day for one year or more. Patients will be excluded if their bone mineral density (BMD) in the spine or hip is more than 1.0 standard deviation (SD) below the mean of normal adults in the presence of one or more fragility fractures indicating severe osteoporosis. If severe osteoporosis is diagnosed, the patient must be excluded from the investigational study. If the patient has osteoporosis or osteopenia, they may be included in the study if he or she meets the rest of the and