[Primary study of relationship between lumbar degenerative disease and morbidity of primary knee osteoarthritis].

OBJECTIVE: To study the relationship between lumbar degenerative disease and morbidity of primary unilateral knee osteoarthritis. METHODS: The clinical data of 115 unilateral knee osteoarthritis patients and 119 bilateral knee osteoarthritis patients undergoing TKR (total knee replacement) at our hospital in 2008 were retrospectively analyzed. According to clinical signs of lumbar degenerative disease and radiological changes, these patients were divided into upper/lower/whole/none lumbar degenerative disease group respectively. chi(2) test was performed to compare the difference of lumbar degenerative conditions between unilateral knee osteoarthritis and bilateral knee osteoarthritis patients. RESULTS: The morbidity side of lumbar intervertebral disc protrusion or nerve root canal stenosis in primary unilateral osteoarthritis patients was the same as the morbidity side of primary unilateral osteoarthritis. Lumbar degenerative disease morbidity [(34 + 20 + 15)/115 = 60%] of primary unilateral knee osteoarthritis was higher than that [(3 + 5 + 4 + 6 + 19)/119 = 31.1%] of primary bilateral knee osteoarthritis (chi(2) = 19.723, P = 0.000);Upper lumbar degenerative disease morbidity (34/115 = 29.6%)of primary unilateral knee osteoarthritis was higher than that [(3 + 5)/119 = 6.7%] of primary bilateral knee osteoarthritis, (chi(2) = 20.720, P = 0.000); lower lumbar degenerative disease morbidity (20/115 = 17.4%)of primary unilateral knee osteoarthritis was higher than that [(4 + 6)/119 = 8.4%] of primary bilateral knee osteoarthritis (chi(2) = 4.227, P = 0.040); there was no difference for whole lumbar degenerative disease morbidity between primary unilateral and bilateral knee osteoarthritis patients (chi(2) = 0.402, P = 0.526). CONCLUSION: The primary unilateral knee osteoarthritis morbidity is correlated with lumbar degenerative disease for the same elder patient. Upper lumbar degenerative disease can induce the incidence and aggravation of primary unilateral knee osteoarthritis; the flexion deformity of primary knee osteoarthritis may cause the aggravation of lower lumbar degenerative disease, even upper lumbar degenerative disease.