Surgical Outcome Prognosis for the Patients with Degenerative Lumbar Spine Disease Y.I. Zhuravlev, G.I. Nazarenko, A.M. Cherkashov, V.V. Ryazanov, A.G. Nazarenko

«Knowledge to foresee in order to be able» To develop algorithms for outcome prognosis for the patients with degenerative lumbar spine disease Auguste Comte Objective:

Groups of Patients 1-st group Radiofrequency destruction of facet nerves (RFG) 185 patients, average age 54.7 years 2-nd group Percutaneous laser discectomy of lumbar discs with clinically significant protrusion detected (LD) 3-rd group Microdiscectomy at one or more levels with intervertebral disc extrusion without stabilization of vertebral segments (MLD) 4-th group Discectomy followed by stabilization, (Fusion) 39 patients, average age 44.6 years 182 patients, average age 44.3 years 105 patients, average age 47 years patients with degenerative lumbar spine diseases were operated on from 1997 through 2010

4-th group Groups of Patients 2-nd group 1-st group 3-rd group

Surgical Outcome Surgical outcome was assessed according to the modified criteria of Kawabata et al. (1973) Marked improvement and no disabilities (minor sensory deficit and paresis grade 4/5 with improvement at least 1 grade) I good (class 1) Some residual symptoms (minor complaints) and abnormal objective findings (minor sensory deficit, mild atrophy, and paresis grade 3/5 or 4/5 with improvement on at least one grade) II fair (class 2) Poor, no improvement (major complaints, marked deficits and atrophy) or deterioration III poor (class 3)

II poor (class 2) I good (class 1) Association of Classes I good (class 1) II fair (class 2) III poor (class 3)

NList of symptoms Points 012 1Low back painnonesometimesalways 2Cross Lasegue symptomnegative < Low extremities muscles paresis nonegrade 3-4grade Knee-jerk reactionnormalassymetricabsent on both sides 5 Achilles-jerk reactionnormalassymetricabsent on both sides 7X-ray features of degenerative disease no1 segment2 and > segments 8 Degeneration on MRI and CTno1 segment2 and > segments 9 Disc herniationnoprotrusionextrusion/sequestration  Measures for the Patient Evaluation, 28 Symptoms

I good (class 1) II poor (class 2) Data was analyzed with original “RECOGNITION” software, allowing the application of the patients’ identification algorithm to the possible outcomes Recognition Software DATABASE Recognition Software

For prognosis building following methods have been applied: Prognosis Methods Recognition Software Test Recognition Algorithm (TRA) Decision Trees (DT) Logical Patterns (LP)

Outcome prognosis was based on collective decision of these methods («voting») Voting Principle Recognition Software Test Recognition Algorithm (TRA) Decision Trees (DT) Logical Patterns (LP) II poor (class 2) I good (class 1) II poor (class 2) II poor (class 2)

Prognostic Accuracy (rate of correct answers at cross-validation) Group I For radiofrequency destruction of facet nerves 89.7 – 100% Group II Group III Group IV For laser discectomy 89.7 – 100% For microdiscectomy 93.8 – 99.2% For spinal stabilization 87.9 – 96.9%

Registry Architecture

Conclusion Algorithms obtained can be used for the outcome prognosis of the arbitrary new patients. The prognostic system allows to select an optimal operation type for the patients with degenerative lumbar spine disease

Prognosis module is a part of «Russian Spine Registry» Prognosis module of «Russian Spine Registry» is available in English language