腰部脊柱管狭窄（第4腰椎神経根障害）と変形性股関節症における歩行容態の相違点―工学系動作解析法による評価

Differences in Gait Characteristics between Lumbar Spinal Canal Stenosis (L4 Radiculopathy) and Osteoarthritis of the Hip Evaluated by a New Method of Motion Analysis

　大腿部痛に対する鑑別診断が重要である腰部脊柱管狭窄(特に第4腰椎神経根症状)と変形性股関節症に対し，トレッドミルを用いた工学系動作解析法を応用し両者の歩行容態を比較した．前者では，接地直後の生理的な膝屈曲動作の増大を認め，これは大腿四頭筋の軽微な筋力低下を反映する現象と考えた．後者では，股関節可動域の低下を認め，これは解剖学的運動制限に加え，股関節伸展時の関節内圧の上昇によって生じる疼痛の回避を目的とした歩行戦略の結果と考えた．本法は，両者を簡便かつ非侵襲的に鑑別する手段として有用であった．

　We investigated the gait characteristics of patients with lumbar spinal canal stenosis (L4 radiculopathy) and patients with osteoarthritis of the hip by using a treadmill and motion analysis method.　The physiological knee flexion movements of the patients with L4 radiculopathy, during the early stance phase were deeper, suggesting a decrease in the muscle strength of the quadriceps femoris secondary to low-grade paralysis.　In the group with osteoarthritis of the hip, the range of motion of the hip joint was decreased, presumably as a result of two possible causes：the degenerative hip deformity itself and/or a self-control reaction to avoid pain resulting from increased internal pressure on the hip joint in the fully extended position.　This examination was useful as a simple and noninvasive method of differential diagnosis.