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International Journal of Urology (2014) 21, 729–731
doi: 10.1111/iju.12404
Short Communication
Hip dysfunction-related urinary incontinence: A prospective analysis of 189 female patients undergoing total hip arthroplasty Tatsuya Tamaki,1,2 Kazuhiro Oinuma,1 Hideaki Shiratsuchi,1 Keiichi Akita2 and Satoshi Iida3 1
Joint Replacement Center, Funabashi Orthopedic Hospital, Funabashi, Chiba, 2Unit of Clinical Anatomy, Graduate School, Tokyo Medical and Dental University, Tokyo, and 3Orthopedic Department, Matsudo City Hospital, Matsudo, Chiba, Japan
Abbreviations & Acronyms FH = femoral head GT = greater trochanter ICIQ-SF = International Consultation on Incontinence Questionnaire-Short Form JOA = Japanese Orthopedic Association THA = total hip arthroplasty UB = urinary bladder Correspondence: Tatsuya Tamaki M.D., Funabashi Orthopedic Hospital, 1-833 Hazama, Funabashi, Chiba 274-0822, Japan. Email: [email protected] Received 21 October 2013; accepted 7 January 2014. Online publication 4 March 2014
Abstract: Patients reporting that their symptoms of urinary incontinence have decreased after total hip arthroplasty can be encountered in orthopedic practice. In this questionnairebased study, we prospectively evaluated the symptoms of urinary incontinence before and after total hip arthroplasty. The International Consultation on Incontinence QuestionnaireShort Form was used to prospectively evaluate these symptoms in 189 consecutive female patients undergoing total hip arthroplasty. The patients were asked to fill in a questionnaire before and 3 months after surgery. A decrease in the International Consultation on Incontinence Questionnaire-Short Form score of ≥1 point was defined as an improvement, whereas an increase of ≥1 point was defined as worsening. A total of 81 (43%) patients reported urinary incontinence before total hip arthroplasty. At 3 months after surgery, symptoms of urinary incontinence were improved in 64% of these patients, remained unchanged in 32% and worsened in 4%. Mean International Consultation on Incontinence Questionnaire-Short Form score in patients with urinary incontinence before surgery significantly improved from 6.0 to 3.5 (P = 0.0002). These findings suggest a relationship between hip joint function and pelvic floor function, and consequently a hip dysfunction-related urinary incontinence. Key words: pelvic floor, total hip arthroplasty, urinary incontinence.
Introduction Osteoarthritis of the hip is an important cause of pain and disability. In Japan, a majority of patients have secondary osteoarthritis primarily because of congenital dislocation or acetabular dysplasia, and the prevalence is high among elderly women.1–3 THA is one of the most frequently carried out surgeries for improving a patient’s quality of life, and has been proved to be a successful technique.4 In daily practice, we sometimes encounter patients who state that their urinary incontinence symptoms have either diminished or disappeared after THA. To the best of our knowledge, there have been no reports on the effects of hip surgery on urinary incontinence. Therefore, we designed and carried out a questionnaire-based study to prospectively evaluate urinary incontinence before and after THA.
Methods Data on the incidence of incontinence as well as hip function was gathered from 189 female patients (mean age 62.3 years) with hip osteoarthritis who had undergone primary THA between October 2010 and August 2011. Simultaneous bilateral THA had been carried out in 30 of these patients. All THA were carried out using the muscle-sparing, direct anterior approach.5–7 Postoperative rehabilitation had been initiated on the first day. Both active and passive motion exercises for the affected joints and full weight bearing were allowed on the first day. We asked patients to fill the ICIQ-SF8 before and again at 3 months after surgery. We defined a decrease in ICIQ-SF score of ≥1 point as amelioration, and an increase of ≥1 point as worsening. In the present study, a score of ≥1 point for the question “How often do you leak urine?” was considered as incontinence. In addition, hip function was evaluated using the JOA hip score.9 The maximum JOA hip score is 100 points and sums up the separate scores for pain (40 points), range of movement (20 points), gait (20 points), and activities of daily living (20 points). The Student’s paired or unpaired t-test was applied to evaluate differences, and the level of statistical significance applied was P < 0.05. The study was carried out with the approval of the institutional review board of the Funabashi Orthopedic Hospital. © 2014 The Japanese Urological Association
729
T TAMAKI ET AL.
Table 1
(a)
Changes in ICIQ-SF scores in incontinent group (n = 81) Before surgery
After surgery
P-value
UB
(mean ± standard deviation) Question 1 Question 2 Question 3 Total score
1.8 ± 1.3 2.3 ± 1.1 2.1 ± 1.6 6.0 ± 2.9
1.0 ± 1.0 1.4 ± 1.1 1.0 ± 1.2 3.5 ± 2.9
FH P = 0.000149 P = 0.000114 P = 0.000111 P = 0.000244
Table 2 Number of patients’ responses to the question, “When does urine leak?” for patients who had urinary incontinence symptom before surgery (n = 81) When you cough or sneeze Before you can get to the toilet When you are physically active/exercising When you are asleep When you have finished urinating and are dressed
53 (65%) 43 (53%) 7 (9%) 1 (1%) 1 (1%)
Results No orthopedic complications, such as venous thromboembolism, dislocation, infection or early implant migration, were reported. Before THA, 81 out of 189 patients (43%) reported urinary incontinence (incontinent group), whereas 108 (57%) did not (continent group). The mean age was 64.0 ± 9.9 years (mean ± standard deviation) for the incontinent and 61.1 ± 11.2 years for continent groups. JOA hip score in the incontinent and continent groups was 45.2 ± 10.6 and 45.9 ± 11.8, respectively. There was no significant intergroup difference in mean age (P = 0.063) and JOA hip score (P = 0.431). In the incontinent group, the symptoms of urinary incontinence ameliorated in 52 patients (64%), remained unchanged in 26 (32%) and worsened in three (4%) after THA. In the continent group, the symptoms of urinary incontinence remained unapparent in 105 (97%) patients and worsened in three (3%). The mean total ICIQ-SF score in patients who had urinary incontinence before surgery significantly improved from 6.0 to 3.5. Changes in ICIQ-SF scores before and after surgery are shown in Table 1. Table 2 presents the responses to the question, “When does urine leak?”; 55 (65%) patients responded, “When coughing or sneezing.”
Discussion Hip osteoarthritis is an important cause of pain and disability. In Japan, a majority of patients have secondary osteoarthritis primarily as a result of congenital dislocation or acetabular dysplasia, and the prevalence is high among middle-aged and elderly women.1–3 Urinary incontinence is also reported as a common and distressing problem in middle-aged and elderly women.10,11 To the best of our knowledge, this is the first report describing the possible relationship between hip dysfunction and urinary incontinence. We found that 43% of patients undergoing THA suffered from urinary incontinence before surgery. Although some of 730
FH
∗
∗
GT
GT
(b)
GT
FH
∗
UB
∗
FH
GT
Fig. 1 Magnetic resonance imaging of a 28-year-old woman without hip symptoms. (a) T1-weighted axial image at the level of the hip center. The obturator internus muscle (asterisk) originates from the pelvic floor, and its fibers leave the pelvis and unite into a single tendon (white arrow head), which is inserted into the medial surface of the greater trochanter. (b) T2-weighted coronal image of the same subject showing a close relationship between the obturator internus and levator ani muscles (black arrowhead).
these patients might have suffered from functional incontinence as a result of hip dysfunction before surgery, stress urinary incontinence seemed to be the most common form. After surgery, the ICIQ-SF score improved in 64% of patients who suffered from urinary incontinence before surgery. The results of the present study suggest that there is a relationship between hip and pelvic floor functions, as well as a possible existence of urinary incontinence resulting from hip dysfunction. Descensus of the bladder and urethra as a result of loose pelvic floor musculature has been reported to be strongly associated with the pathogenesis of stress urinary incontinence.12 We focused on the obturator internus muscle, which originates from the pelvic floor and has a close relationship with the levetor ani muscle. The obturator internus muscle originates on the medial surface of the obturator membrane at the margin of the obturator foramen.13,14 The muscle fibers of the obturator internus leave the pelvis and unite into a single tendon, which is inserted into the medial surface of the greater trochanter (Fig. 1a,b).13 The levator ani originates partly from the fascia of the obturator internus, and plays an important role in continence and pelvic organ support.14 Muscles around the hip are usually atrophic in patients with hip osteoarthritis (Fig. 2), and tension in these muscles appears to decrease with atrophy and limitation of the hip’s range of motion. After THA, these muscles can be tensioned as a result of the muscle strengthening and improvement of the hip’s range of motion. We therefore hypothesize that a loose pelvic floor could be improved by THA. The results of the present study suggest that general © 2014 The Japanese Urological Association
Hip dysfunction-related incontinence
Conflict of interest None declared. FH GT
UB
∗
References
FH GT
Fig. 2 A coronal computed tomographic image of a 66-year-old woman suffering from left hip osteoarthritis showing significant atrophy of the left obturator internus muscle (asterisk). White arrow head, levator ani muscle.
health-related quality of life can be improved after surgery, not only in terms of walking ability or pain, but also urinary incontinence. After THA, urinary incontinence became more severe in 4% and 3% of patients in the incontinent and continent groups, respectively. The ICIQ-SF score can vary for the same symptom in the same patient, because the evaluation is subjective and activities of daily living can change because of improvement in hip function after THA. There were several limitations to the present study. First, there was no control group. Second, because the follow-up period was 3 months, it remained unclear when urinary incontinence had diminished. Finally, the number of childbirth or underlying urogynecological diseases was not specifically analyzed in the present study. Further investigations including urological examinations are required to address these issues. We prospectively investigated the prevalence of urinary incontinence before and after THA. Mean ICIQ-SF score in patients with urinary incontinence before surgery improved by 64% after THA. These results suggest a relationship between hip dysfunction and urinary incontinence.
© 2014 The Japanese Urological Association
1 Inoue K, Wicart P, Kawasaki T et al. Prevalence of hip osteoarthritis and acetabular dysplasia in French and Japanese adults. Rheumatology (Oxford) 2000; 39: 745–8. 2 Nakamura S, Ninomiya S, Nakamura T. Primary osteoarthritis of the hip joint in Japan. Clin. Orthop. Relat. Res. 1989; 24: 190–6. 3 Yoshimura N, Campbell L, Hashimoto T et al. Acetabular dysplasia and hip osteoarthritis in Britain and Japan. Br. J. Rheumatol. 1998; 37: 1193–7. 4 Laupacis A, Bourne R, Rorabeck C et al. The effect of elective total hip replacement on health-related quality of life. J. Bone Joint Surg. Am. 1993; 75: 1619–26. 5 Joel MM, Cambize S, Tania F. Single-incision anterior approach for total hip arthroplasty on an orthopaedic table. Clin. Orthop. Relat. Res. 2005; 441: 115–24. 6 Kennon RE, Keggi JM, Wetmore RS, Zatorski LE, Huo MH, Keggi KJ. Total hip arthroplasty through a minimally invasive anterior surgical approach. J. Bone Joint Surg. Am. 2003; 85-A (Suppl 4): 39–48. 7 Oinuma K, Eingartner C, Saito Y, Shiratsuchi H. Total hip arthroplasty by a minimally invasive, direct anterior approach. Oper. Orthop. Traumatol. 2007; 19: 310–26. 8 Avery K, Donovan J, Peters TJ, Shaw C, Gotoh M, Abrams P. ICIQ: a brief and robust measure for evaluating the symptoms and impact of urinary incontinence. Neurourol. Urodyn. 2004; 23: 322–30. 9 Toyama H, Endo N, Sofue M, Dohmae Y, Takahashi HE. Relief from pain after Bombelli’s valgus-extension osteotomy and effectiveness of the combined shelf operation. J. Orthop. Sci. 2000; 5: 114–23. 10 Hunskaar S, Burgio K, Diokno A, Herzog AR, Hjälmås K, Lapitan MC. Epidemiology and natural history of urinary incontinence in women. Urology 2003; 62: 16–23. 11 Hunskaar S, Lose G, Sykes D, Voss S. The prevalence of urinary incontinence in women in four European countries. BJU Int. 2004; 93: 324–30. 12 Bø K. Pelvic floor muscle training is effective in treatment of female stress urinary incontinence, but how does it work? Int. Urogynecol. J. 2004; 15: 76–84. 13 Shinohara H. Gemelli and obturator internus muscles: different heads of one muscle? Anat. Rec. 1995; 243: 145–50. 14 Stein TA, DeLancey JO. Structure of the perineal membrane in females: gross and microscopic anatomy. Obstet. Gynecol. 2008; 111: 686–93.
731
International Journal of Urology (2014) 21, 729–731
doi: 10.1111/iju.12404
Short Communication
Hip dysfunction-related urinary incontinence: A prospective analysis of 189 female patients undergoing total hip arthroplasty Tatsuya Tamaki,1,2 Kazuhiro Oinuma,1 Hideaki Shiratsuchi,1 Keiichi Akita2 and Satoshi Iida3 1
Joint Replacement Center, Funabashi Orthopedic Hospital, Funabashi, Chiba, 2Unit of Clinical Anatomy, Graduate School, Tokyo Medical and Dental University, Tokyo, and 3Orthopedic Department, Matsudo City Hospital, Matsudo, Chiba, Japan
Abbreviations & Acronyms FH = femoral head GT = greater trochanter ICIQ-SF = International Consultation on Incontinence Questionnaire-Short Form JOA = Japanese Orthopedic Association THA = total hip arthroplasty UB = urinary bladder Correspondence: Tatsuya Tamaki M.D., Funabashi Orthopedic Hospital, 1-833 Hazama, Funabashi, Chiba 274-0822, Japan. Email: [email protected] Received 21 October 2013; accepted 7 January 2014. Online publication 4 March 2014
Abstract: Patients reporting that their symptoms of urinary incontinence have decreased after total hip arthroplasty can be encountered in orthopedic practice. In this questionnairebased study, we prospectively evaluated the symptoms of urinary incontinence before and after total hip arthroplasty. The International Consultation on Incontinence QuestionnaireShort Form was used to prospectively evaluate these symptoms in 189 consecutive female patients undergoing total hip arthroplasty. The patients were asked to fill in a questionnaire before and 3 months after surgery. A decrease in the International Consultation on Incontinence Questionnaire-Short Form score of ≥1 point was defined as an improvement, whereas an increase of ≥1 point was defined as worsening. A total of 81 (43%) patients reported urinary incontinence before total hip arthroplasty. At 3 months after surgery, symptoms of urinary incontinence were improved in 64% of these patients, remained unchanged in 32% and worsened in 4%. Mean International Consultation on Incontinence Questionnaire-Short Form score in patients with urinary incontinence before surgery significantly improved from 6.0 to 3.5 (P = 0.0002). These findings suggest a relationship between hip joint function and pelvic floor function, and consequently a hip dysfunction-related urinary incontinence. Key words: pelvic floor, total hip arthroplasty, urinary incontinence.
Introduction Osteoarthritis of the hip is an important cause of pain and disability. In Japan, a majority of patients have secondary osteoarthritis primarily because of congenital dislocation or acetabular dysplasia, and the prevalence is high among elderly women.1–3 THA is one of the most frequently carried out surgeries for improving a patient’s quality of life, and has been proved to be a successful technique.4 In daily practice, we sometimes encounter patients who state that their urinary incontinence symptoms have either diminished or disappeared after THA. To the best of our knowledge, there have been no reports on the effects of hip surgery on urinary incontinence. Therefore, we designed and carried out a questionnaire-based study to prospectively evaluate urinary incontinence before and after THA.
Methods Data on the incidence of incontinence as well as hip function was gathered from 189 female patients (mean age 62.3 years) with hip osteoarthritis who had undergone primary THA between October 2010 and August 2011. Simultaneous bilateral THA had been carried out in 30 of these patients. All THA were carried out using the muscle-sparing, direct anterior approach.5–7 Postoperative rehabilitation had been initiated on the first day. Both active and passive motion exercises for the affected joints and full weight bearing were allowed on the first day. We asked patients to fill the ICIQ-SF8 before and again at 3 months after surgery. We defined a decrease in ICIQ-SF score of ≥1 point as amelioration, and an increase of ≥1 point as worsening. In the present study, a score of ≥1 point for the question “How often do you leak urine?” was considered as incontinence. In addition, hip function was evaluated using the JOA hip score.9 The maximum JOA hip score is 100 points and sums up the separate scores for pain (40 points), range of movement (20 points), gait (20 points), and activities of daily living (20 points). The Student’s paired or unpaired t-test was applied to evaluate differences, and the level of statistical significance applied was P < 0.05. The study was carried out with the approval of the institutional review board of the Funabashi Orthopedic Hospital. © 2014 The Japanese Urological Association
729
T TAMAKI ET AL.
Table 1
(a)
Changes in ICIQ-SF scores in incontinent group (n = 81) Before surgery
After surgery
P-value
UB
(mean ± standard deviation) Question 1 Question 2 Question 3 Total score
1.8 ± 1.3 2.3 ± 1.1 2.1 ± 1.6 6.0 ± 2.9
1.0 ± 1.0 1.4 ± 1.1 1.0 ± 1.2 3.5 ± 2.9
FH P = 0.000149 P = 0.000114 P = 0.000111 P = 0.000244
Table 2 Number of patients’ responses to the question, “When does urine leak?” for patients who had urinary incontinence symptom before surgery (n = 81) When you cough or sneeze Before you can get to the toilet When you are physically active/exercising When you are asleep When you have finished urinating and are dressed
53 (65%) 43 (53%) 7 (9%) 1 (1%) 1 (1%)
Results No orthopedic complications, such as venous thromboembolism, dislocation, infection or early implant migration, were reported. Before THA, 81 out of 189 patients (43%) reported urinary incontinence (incontinent group), whereas 108 (57%) did not (continent group). The mean age was 64.0 ± 9.9 years (mean ± standard deviation) for the incontinent and 61.1 ± 11.2 years for continent groups. JOA hip score in the incontinent and continent groups was 45.2 ± 10.6 and 45.9 ± 11.8, respectively. There was no significant intergroup difference in mean age (P = 0.063) and JOA hip score (P = 0.431). In the incontinent group, the symptoms of urinary incontinence ameliorated in 52 patients (64%), remained unchanged in 26 (32%) and worsened in three (4%) after THA. In the continent group, the symptoms of urinary incontinence remained unapparent in 105 (97%) patients and worsened in three (3%). The mean total ICIQ-SF score in patients who had urinary incontinence before surgery significantly improved from 6.0 to 3.5. Changes in ICIQ-SF scores before and after surgery are shown in Table 1. Table 2 presents the responses to the question, “When does urine leak?”; 55 (65%) patients responded, “When coughing or sneezing.”
Discussion Hip osteoarthritis is an important cause of pain and disability. In Japan, a majority of patients have secondary osteoarthritis primarily as a result of congenital dislocation or acetabular dysplasia, and the prevalence is high among middle-aged and elderly women.1–3 Urinary incontinence is also reported as a common and distressing problem in middle-aged and elderly women.10,11 To the best of our knowledge, this is the first report describing the possible relationship between hip dysfunction and urinary incontinence. We found that 43% of patients undergoing THA suffered from urinary incontinence before surgery. Although some of 730
FH
∗
∗
GT
GT
(b)
GT
FH
∗
UB
∗
FH
GT
Fig. 1 Magnetic resonance imaging of a 28-year-old woman without hip symptoms. (a) T1-weighted axial image at the level of the hip center. The obturator internus muscle (asterisk) originates from the pelvic floor, and its fibers leave the pelvis and unite into a single tendon (white arrow head), which is inserted into the medial surface of the greater trochanter. (b) T2-weighted coronal image of the same subject showing a close relationship between the obturator internus and levator ani muscles (black arrowhead).
these patients might have suffered from functional incontinence as a result of hip dysfunction before surgery, stress urinary incontinence seemed to be the most common form. After surgery, the ICIQ-SF score improved in 64% of patients who suffered from urinary incontinence before surgery. The results of the present study suggest that there is a relationship between hip and pelvic floor functions, as well as a possible existence of urinary incontinence resulting from hip dysfunction. Descensus of the bladder and urethra as a result of loose pelvic floor musculature has been reported to be strongly associated with the pathogenesis of stress urinary incontinence.12 We focused on the obturator internus muscle, which originates from the pelvic floor and has a close relationship with the levetor ani muscle. The obturator internus muscle originates on the medial surface of the obturator membrane at the margin of the obturator foramen.13,14 The muscle fibers of the obturator internus leave the pelvis and unite into a single tendon, which is inserted into the medial surface of the greater trochanter (Fig. 1a,b).13 The levator ani originates partly from the fascia of the obturator internus, and plays an important role in continence and pelvic organ support.14 Muscles around the hip are usually atrophic in patients with hip osteoarthritis (Fig. 2), and tension in these muscles appears to decrease with atrophy and limitation of the hip’s range of motion. After THA, these muscles can be tensioned as a result of the muscle strengthening and improvement of the hip’s range of motion. We therefore hypothesize that a loose pelvic floor could be improved by THA. The results of the present study suggest that general © 2014 The Japanese Urological Association
Hip dysfunction-related incontinence
Conflict of interest None declared. FH GT
UB
∗
References
FH GT
Fig. 2 A coronal computed tomographic image of a 66-year-old woman suffering from left hip osteoarthritis showing significant atrophy of the left obturator internus muscle (asterisk). White arrow head, levator ani muscle.
health-related quality of life can be improved after surgery, not only in terms of walking ability or pain, but also urinary incontinence. After THA, urinary incontinence became more severe in 4% and 3% of patients in the incontinent and continent groups, respectively. The ICIQ-SF score can vary for the same symptom in the same patient, because the evaluation is subjective and activities of daily living can change because of improvement in hip function after THA. There were several limitations to the present study. First, there was no control group. Second, because the follow-up period was 3 months, it remained unclear when urinary incontinence had diminished. Finally, the number of childbirth or underlying urogynecological diseases was not specifically analyzed in the present study. Further investigations including urological examinations are required to address these issues. We prospectively investigated the prevalence of urinary incontinence before and after THA. Mean ICIQ-SF score in patients with urinary incontinence before surgery improved by 64% after THA. These results suggest a relationship between hip dysfunction and urinary incontinence.
© 2014 The Japanese Urological Association
1 Inoue K, Wicart P, Kawasaki T et al. Prevalence of hip osteoarthritis and acetabular dysplasia in French and Japanese adults. Rheumatology (Oxford) 2000; 39: 745–8. 2 Nakamura S, Ninomiya S, Nakamura T. Primary osteoarthritis of the hip joint in Japan. Clin. Orthop. Relat. Res. 1989; 24: 190–6. 3 Yoshimura N, Campbell L, Hashimoto T et al. Acetabular dysplasia and hip osteoarthritis in Britain and Japan. Br. J. Rheumatol. 1998; 37: 1193–7. 4 Laupacis A, Bourne R, Rorabeck C et al. The effect of elective total hip replacement on health-related quality of life. J. Bone Joint Surg. Am. 1993; 75: 1619–26. 5 Joel MM, Cambize S, Tania F. Single-incision anterior approach for total hip arthroplasty on an orthopaedic table. Clin. Orthop. Relat. Res. 2005; 441: 115–24. 6 Kennon RE, Keggi JM, Wetmore RS, Zatorski LE, Huo MH, Keggi KJ. Total hip arthroplasty through a minimally invasive anterior surgical approach. J. Bone Joint Surg. Am. 2003; 85-A (Suppl 4): 39–48. 7 Oinuma K, Eingartner C, Saito Y, Shiratsuchi H. Total hip arthroplasty by a minimally invasive, direct anterior approach. Oper. Orthop. Traumatol. 2007; 19: 310–26. 8 Avery K, Donovan J, Peters TJ, Shaw C, Gotoh M, Abrams P. ICIQ: a brief and robust measure for evaluating the symptoms and impact of urinary incontinence. Neurourol. Urodyn. 2004; 23: 322–30. 9 Toyama H, Endo N, Sofue M, Dohmae Y, Takahashi HE. Relief from pain after Bombelli’s valgus-extension osteotomy and effectiveness of the combined shelf operation. J. Orthop. Sci. 2000; 5: 114–23. 10 Hunskaar S, Burgio K, Diokno A, Herzog AR, Hjälmås K, Lapitan MC. Epidemiology and natural history of urinary incontinence in women. Urology 2003; 62: 16–23. 11 Hunskaar S, Lose G, Sykes D, Voss S. The prevalence of urinary incontinence in women in four European countries. BJU Int. 2004; 93: 324–30. 12 Bø K. Pelvic floor muscle training is effective in treatment of female stress urinary incontinence, but how does it work? Int. Urogynecol. J. 2004; 15: 76–84. 13 Shinohara H. Gemelli and obturator internus muscles: different heads of one muscle? Anat. Rec. 1995; 243: 145–50. 14 Stein TA, DeLancey JO. Structure of the perineal membrane in females: gross and microscopic anatomy. Obstet. Gynecol. 2008; 111: 686–93.
731
