Abstract
Introduction
In the 1970's, Kirkaldy-Willis first described the “Degenerative Cascade” of DDD. Observation of demographic studies shows more back pain in younger adults (30 to 50 years) than in elderly adults (over 60 years) in which osteoarthritis problems are prevalent to disc problems. The aim of this study is to demonstrate if and when an interlaminar elastic motion preservation device for disc assistance can stop or reverse the degenerative cascade of the lumbar spine in younger adults. We used in this study a new motion preservation device not interspinous but interlaminar. The IntraSpine® device (Cousin Biotech, France), is manufactured in medical silicon 65 shore coated by an adherent pure polyester terephtalate sleeve and the frontal extremity is further covered by a silicone film that prevents adhesion to the neural structures in cases of surgical bone or soft tissue removal.
Material and Methods
Group 1: 60 patients (mean age 34.5 years, 38 female an 22 male) affected from back pain from a minimum time of two years and after the failure of conservative treatment for at least 6 months, received a minimally invasive surgical procedure implanting this IntraSPINE® device at one or two levels. Group 2: 54 patients (mean age 32,6 years, 24 male and 16 female) affected from big extruded disc hernia received the some implant after the removal of the hernia in the some surgical procedure at one level, to prevent the subsequent chronic LBP due to a rapid collapse of the disc height. From the literature we know that in this young group of patients the percentage of the chronic LBP in the late follow up (5 years) it's ~70%. The results with a minimum follow-up of 4 years were evaluated from the clinical point of view regarding the LBP with VAS and ODI tests. All patients were also subjected to an MRI control. The surgical procedure was performed by monolateral approach and in many cases in local anesthesia in group 1 and in general anesthesia and equally by monolateral approach in group 2. The source of the pain in this group of patients (facet joint pain) was demonstrated by a positive response to the facet joint block test (The response was considered positive for a transient reduction of pain at least of 70%). Prior to surgical procedure, all patients underwent an MRI, a CT Scan and a dynamic X-ray of the lumbar spine. The stage of the degenerative cascade was between grade III and IV according to Pfirrmann.
Results
Group 1:in ~20% also in presence of good clinical results we highlighted a moderate progression of the cascade, in about the 50% the Pfirrmann grade was unchanged, but in ~30% we highlighted a partial rehydration of the disc which means a initial reversion of the degenerative cascade (patients with the lower grades of degeneration). Group 2: the percentage of a very uncomfortable LBP in this group was 24%, and the number of the recurrences was 2 (5%) and in only 1 case we performed a new surgical procedure. The maximum amount of blood lost in both group was 80 cc and the mean time of the surgical procedure was 28 minutes (from 18 to 37) in the group 1 and 41 minutes (from 34 to 46) in the group 2.
Conclusion
The close observation of the right indications and the proper selection of patients is strictly recommended. The mininvasive and relatively easy surgical procedure do not induce the surgeons of an indiscriminate use of this device. The wrong level implant is the mast frequent mistake. From the observation of these very important points we believe that are obtained this very good results even should be necessary a big number of case study, a longer follow up and a randomized multicenter study. The absence of major complications, the minimally invasive surgical procedure and the good clinical results allow us to say that with a correct patient selection we can prevent that this disease from acute becomes chronic, and thus its natural progression. Last but not least if we performed this surgical procedure in the earliest stages of the degenerative cascade, we can reverse its trend.