Baba Tomonori, Homma Yasuhiro, Takazawa Naoko, Kobayashi Hideo, Matsumoto Mikio, Aritomi Kentaro, Yuasa Takahito, Kaneko Kazuo
Department of Orthopedic Surgery, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyoku, Tokyo, Japan,
Eur J Orthop Surg Traumatol. 2014 Dec;24(8):1455-60. doi: 10.1007/s00590-014-1413-4. Epub 2014 Jan 10.
We hypothesized that posterior approach (PA) dissecting the short external rotators and anterior approach (AA) not dissecting these have different influences on the pelvic floor muscles and subsequently affect urinary incontinence. The objective of this study was to investigate whether AA advantageously influences symptoms of urinary incontinence.
The subjects were 76 female patients who underwent their primary total hip arthroplasty. The presence or absence of urinary incontinence before and after surgery was surveyed by a direct interview at the time of outpatient examination within a period from 1.5 year after surgery using the international consultation on incontinence questionnaire-short form.
Urinary incontinence improved after surgery in eight patients (22.2%), slightly improved in one (2.8%), remained unchanged in 26 (72.2%), slightly aggravated in one (2.8%) in the AA group. In the PA group, urinary incontinence improved after surgery in one (2.5%), remained unchanged in 30 (75%), slightly aggravated in four (10%), and aggravated in five (12.5%). Symptoms of urinary incontinence were significantly improved in the AA group and aggravated in the PA group (Mann-Whitney U test, P = 0.0057).
As the anatomical characteristic of the short external rotators, the root of the internal obturator muscle is connected to the levator ani muscle. Among the pelvic floor muscles, this levator ani muscle is closely involved in supporting the pelvic organs. Since the short external rotators may have been atrophied due to hip joint dysfunction before surgery, if the strength of this muscle group recovers, support of the pelvic organs and urinary incontinence may be improved. It was assumed that surgery through AA improved external rotation contracture of the hip joint and leg length, which increased tension of the internal obturator muscle, with which tension of the pelvic floor muscle also increased and improved urinary incontinence.
我们假设，后入路（PA）切断短外旋肌，而前入路（AA）不切断这些肌肉，对盆底肌肉有不同影响，进而影响尿失禁。本研究的目的是调查AA是否对尿失禁症状有有利影响。
研究对象为76例行初次全髋关节置换术的女性患者。在术后1.5年至术后一段时间内的门诊检查时，通过直接访谈，使用国际尿失禁咨询问卷简表，调查手术前后尿失禁的情况。
AA组中，术后尿失禁改善的有8例（22.2%），稍有改善的1例（2.8%），无变化的26例（72.2%），稍有加重的1例（2.8%）。PA组中，术后尿失禁改善的1例（2.5%），无变化的30例（75%），稍有加重的4例（10%），加重的5例（12.5%）。AA组尿失禁症状显著改善，而PA组加重（曼-惠特尼U检验，P = 0.0057）。
由于短外旋肌的解剖特点，闭孔内肌根部与肛提肌相连。在盆底肌肉中，肛提肌密切参与支持盆腔器官。由于术前髋关节功能障碍，短外旋肌可能已萎缩，若该肌群力量恢复，盆腔器官的支撑及尿失禁情况可能改善。推测通过AA进行的手术改善了髋关节外旋挛缩和腿长，增加了闭孔内肌的张力，盆底肌肉的张力也随之增加，从而改善了尿失禁。
