ASSESSMENT OF ADJACENT-SEGMENT DISEASE IN PATIENTS TREATED WITH CERVICAL FUSION OR ARTHROPLASTY: A PROSPECTIVE 2-YEAR STUDY C A S E S T U D Y – C O R Y J E N S E N

ADJACENT-SEGMENT DISEASE

Name: Assessment of Adjacent-segment disease in patients treated with cervical fusion or arthroplasty: a prospective 2-year study

James T. Robertson – Dept. of Neurosurgery, Univ. of Tennessee Health Science Center

Stephen M. Papadopoulos – Barrow Neurological Inst., Phoenix, AZVincent C. Traynelis – Dept. of Neurosurgery, Univ. of Iowa, Iowa

City, Iowa

GOAL/PURPOSE OF STUDY

To compare evidence of radiologically documented changes in adjacent-level cervical disc disease after a single level discectomy and cervical fusion.

STUDY PARAMETERS

The goal of both was to treat the symptoms of DDD in the Cervical region. The majority of patients were single level herniated disk or spondylosis (degeneration of body).

Post-Op evidence that they were looking for:

New anterior osteophytes Enlargement of existing osteophytes Narrowing of adjacent disc space >30%

HOW WAS THE STUDY (OSTEO)CONDUCTED?

Compared the outcomes of patients using the Affinity Cervical Cage system, and the Bryan Artificial Cervical disc.

Examined Radiography for signs of Adjacent-Level Disk disease

New anterior osteophyte formation, increased narrowing of an interspace, new DDD, and calcification of the anterior longitudinal ligament.

HOW WAS THE STUDY (OSTEO)CONDUCTED?

• Affinity Cage study started 2/15/97, and the last patient was treated 11/15/98.

• The Bryan Study started January 2000, and the last patient follow up review was June 2004.

• The patients were examined 24 months post-op to examine results

COMPARATIVE X-RAYS

Bryan Artificial Cervical disc.Normal Anterior Single-Level Fusion

WHAT DID THEY DO?

Single-level Cervical Discectomy for patients with single level herniated disk or spondylosis producing radiculopathy and/or myelopathy from c2-3 to c7-t1.

103 patients used the Bryan Artificial Cervical Disk 103 patients ranging from 28-97 yrs old. Mean age of 55.9 61 women 41 men158 patients used the Affinity Cervical Cage system

78 men, mean 45.5 80 women, mean 44

AFFINITY CERVICAL CAGE SYSTEM

• The AFFINITY® system uses a simple, easy-to-implant threaded cage, indicated for single-level ACDF’s

• Its tapered design provides for optimal restoration of normal cervical Lordosis

BRYAN ARTIFICIAL CERVICAL DISC

• Designed to closely act as a Vertebral disk

• Not intended for fusion• Created to keep natural

motion of the spine

Video: https://www.youtube.com/watch?v=8N7PB12Xefg

BRYAN ARTIFICIAL CERVICAL DISC

COMPARISON/OUTCOME

• Radiological review demonstrated new anterior osteophyte formation in 17.8% of Affinity cage, and 10.8% of Bryan Disc.

• Osteophyte enlargement was documented in 8.9% of Affinity patients, 0% for Bryan System

• Increase in DDD was present in 3.8% of Affinity, 4% Bryan

• New DDD was 1.9% Affinity, 1.3% Bryan• DDD is based off >30% increase in disc narrowing• New radiographic changes – 34.6% Affinity, 17.5%

Bryan

COMPARISON/OUTCOME

• For Affinity 85% of new osteophytes appeared in superior space, 15% inferior

• For Bryan, only 1 inferior osteophyte was produced • Symptomatic DDD occurred in 7% using the Affinity

system, 0 for Bryan• 11 Adjacent herniated discs happened with Affinity,

1 for Bryan System• Medical treatment was needed in 33% of Affinity

cases for neck, shoulder, and/or arm pain. 1.3% for Bryan.

• For Bryan, only 1 patient required adjacent-level surgery for symptomatic disc disease.

CONCLUSION OF STUDY• Advocates of procedures in which an anterior

discectomy is followed by a moveable prosthesis has found that preserving motion will eliminate or diminish the prevalence of adjacent-level DD.

• This study shows that arthrodesis is very commonly followed by radiographic changes of adjacent-level disease.

• Based on the radiographic and clinical evidence, it appears that maintaining motion (Bryan) after a single level anterior discectomy will delay or prevent symptomatic disc disease, and will decrease to a significant degree the adjacent-level DD.

CONCLUSION OF STUDY

• Also, fusion is associated with a morbidity rate of 6.4% from non-union. Repeat operation needed.

• Based on the radiographic and clinical evidence, it appears that maintaining motion (Bryan) after a single level anterior discectomy will delay or prevent symptomatic disc disease, and will decrease to a significant degree the adjacent-level DD.

THINGS TO CONSIDERDisclosure: Dr. Robertson is the Medical Director of the Cervical Division of

Medtronic Sofamor Danek. Drs. Papadopoulos and Traynelis are Consultants of Medtronic

Sofamor Danek.

Was the Study well done? Yes Strict qualifications to join the study created an even playing field

Bryan – Started at 103, ended at 74 Affinity Cage – Started at 202 ended at 158 Eliminated for pre-existing conditions and prior spine surgeries