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Obturator hernia presenting as small bowel obstruction
Obturator Hernia Presenting as Small Bowel Obstruction Chung Yau Lo, FRCS (Edin), Theo G. Lorentz, ah, FRCS (England), Peter W.K. Lau, FRCS (aasg), Hong Kong
Obturator hernia is a rare but important cause of small bowel obstruction that is associated with difficult diagnosis and high mortality. In the past 7 years, 16 patients with small bowel obstruction due to obturator hernia diagnosed at operation were seen at the Department of Surgery, the University of Hong Kong, Queen Mary Hospital. They represented 1% (16 of 1,554) of all hernia repair performed and 1.6% (16 of 1,000) of mechanical intestinal obstruction encountered during the same period.’ Elderly emaciated women with chronic disease were commonly affected. All patients presented with partial or complete mechanical small bowel obstruction. R@bt-sided obturator hernia outnumbered left-sided hernia, and bilateral hernia was found in only one patient. The majority of patients required resection of their strangulated small bowel. Most of the hernial orifices were closed with interrupted nonabsorbable sutures. Morbidity and mortality rates were significantly high for this group of debilitated patients with chronic disease who underwent late operation for tbis elusive diagnosis.
0
bturator hernia is an uncommon but important cause of intestinal obstruction because of its difficult diagnosis and high mortality rate. The condition was first described in 1724 by Arnaud de Ronsil of France.’ It remains a rare condition for which a variety of case reports and small series have appeared in the literature. One of the largest series, consisting of 12 cases of strangulated obturator hernia, was reported by Rogers in 1960.* By 1980, Bjork and associates3 and Sinha and DeCosta4 had collected 541 cases of obturator hernia that had been reported in the English language. Despite all these reports, intestinal obstruction due to obturator hernia remains an elusive diagnosis often made only at laparotomy. In a search of the English literature from 1980 to 1992, we have collected 43 more cases of obturator hernia, which, in addition to the 16 cases we report here, brings the total to 600. The aim of the present study is to report our own experience and to compare this with the previous reports.
From the Department of Surgery, The University of Hong Kong Queen Mary Hospital, Hong Kong. Requests for reprints should be addressed to Dr. Chung Yau Lo, Department of Surgery, The University of Hong Kong, Queen Mary Hospital, Pokulam Road, Hong Kong. Manuscript received October 27, 1992, and accepted in revised form March 8, 1993.
396
THE AMERICAN
JOURNAL
OF SURGERY
VOLUME
167
TABLE I Concomitant Medical Pathologies Medical Patholorries Chronic obstructive pulmonary disease Congestive heart failure lschaemic heart disease Cardiac arrhythmia Hypertension Cirrhosis Diabetes mellitus Tuberculosis or pneumonia Cerebrovascular accident Total (No. of patients)
No. 6 3 3 3 2 2 1 3 1 24 (10)
I
PATIENTS AND METHODS From January 1985 to March 1992, 16 Chinese patients with small bowel obstruction due to obturator hernia diagnosed at operation were seen at the Department of Surgery, the University of Hong Kong, Queen Mary Hospital. Their clinical records were reviewed retrospectively with respect to age, sex, body weight on admission, previous medical illness, clinical presentation, operative findings, treatment received, postoperative outcome, and follow-up. In addition, the number of patients with mechanical intestinal obstruction due to other causes that we encountered and the number of hernia operations we performed during the same period were documented so as to evaluate the relative importance of this condition. RESULTS Patientcharacteristics and clinicalpresentation:There were 14 women and 2 men, for a female-to-male ratio of 7 to 1. The age range was 63 to 97 years, with a mean age of 79 years. Body weight on admission ranged from 30 to 45 kg, with a mean of 39.5 kg. Each patient had an average of 1.5 concomitant medical problems on admission (Table I). All thepatients presented with intestinal obstruction. The presenting symptoms were abdominal pain, vomiting, and abdominal distension. All 16 patients had at least 1 of these symptoms, and 12 patients had all 3 symptoms on admission. Two of them were actually admitted with coffee ground vomitus, which was initially thought to be due to upper gastrointestinal tract bleeding, whereas one patient was admitted with frank generalized peritonitis due to strangulated small bowel with perforation. Only one quarter of-the~patients recalled a past history of a similar attack, within 1 month prior to admission, which resolved spontaneously. The interval between presentation and admission to hospital was 3 days (range: less than 24 hours to 2 weeks). Five patients came from nursing homes,
APRIL 1994
TABLE II
1
TABLE III Operative Findings J!?ua Right Left
Complications
Jeiunum Right Left
Perforated Gangrenous Perforated on reduction Incarcerated
1 4 1 2
2
2’
1
-
1
1’
Total
8
4
3
2
1 1
‘One patient had bilateral involvement.
Morbidity and Mortality No.
Cardiac arrhythmia Congestive heart failure Pneumonia Pneumothorax Gastrointestinal bleeding Wound infection Sepsis
3 1 7 2 1 2 1
Total’
17
Mortality
5
1 6
*Some patients had more than one complication.
whereas two patients were actually transferred from other chronic convalescent hospitals for treatment of other medical conditions. Physical examination on admission in all 16 patients revealed a distended abdomen with high-pitched bowel sounds. Four patients had clinical evidence of local or generalized peritonitis. None of the patients had undergone previous abdominal surgery. Howship-Romberg sign, which refers to ipsilateral groin pain radiating down to the thigh due to irritation of the obturator nerve, was present in only two of the patients. An erect and supine plain abdominal radiograph revealed dilated small bowel loops with multiple air-fluid levels in all 16 patients. The correct diagnosis was suspected preoperatively in six (38%) patients on the basis of the characteristic clinical setting. Despite this, due to a number of factors, the delay between admission and surgery was an average of 3 days (range: less than 24 hours to 6 days). Operative findings and management: Laparotomy was performed through a lower mid-line incision in all the patients. Right-sided obturator hernia outnumbered left-sided hernia (R:L = 10:.5),and bilateral hernia was rare (n = 1). All the patients had small bowel involvement in the hernial sac and evidence of complete or partial small bowel obstruction with proximal dilated and distal collapsed small bowel. The segment of small bowel involved was the ileum in 12 and the jejunum in 5, for a total of 17 hernias (Table II). Nine of these were of the Richter’s type. Reduction of incarcerated small bowel without resection was performed in 3 patients, whereas resection of small bowel was performed in 13 patients who had gangrenous bowel with (n = 6) or without (n = 6) perforation, or nonviable bowel that perforated on reduction (n = 2). The one patient with bilateral involvement had gangrenous Richter’s type of herniation of jejunum on both sides with perforation on the right side. Thirteen hernial orifices in 12 patients were closed by multiple interrupted nonabsorbable sutures, whereas the hernial orifice itself was not treated in 4 patients. The mean estimated blood loss was 180 mL (20 to 500 rnL), whereas the mean operative time was 80 minutes (30 minutes to 2 hours). Morbidity and mortality: Half of this group of poor-risk patients required postoperative ventilation. Four patients died within 30 days after operation resulting in an operative mortality of 25%. Three of them died of postoperative bronchopneumonia, and a 97-year-old woman died of sepsis. Two more patients died during their stay in our con-
_I
valescence hospital on postoperative day 44 and 48, respectively, due to exacerbation of their chronic obstructive pulmonary disease with development of bronchopneumonia, resulting in a hospital mortality of 38%. Seventeen postoperative complications occurred among 10 (63%) patients (Table III). The mean hospital stay was 18 days (range: 6 to 50 days). Follow-up: The surviving 10 patients have been followed up from 1 to 27 months (mean: 9.4 months) without any recurrent obstruction or symptoms due to recurrent hemiation. One patient was readmitted 7 months after the operation with small bowel perforation related to an adhesion band. Emergency laparotomy with small bowel resection was again performed, but the patient died 6 days after the operation because of septicemia. COMMENTS A group of 16 patients with obturator hernia presenting with small bowel obstruction diagnosed at operation was encountered in our department during the past 7 years. They represented 1% of the 1,554 hernia operations performed during this period, which is much higher than that reported by Bjork and associates (0.073%).3 Rogers2 reported 12 cases of obturator hernia among 3,000 patients with mechanical intestinal obstruction treated at the Los Angeles County General Hospital (0.4%). In our series, we found 16 cases of obturator hernia among 1,000 patients with mechanical intestinal obstruction within the same period (1.6%). These figures suggest a higher incidence of obturator hernia in our Chinese population. The characteristic clinical profile of our patients was that of an elderly, emaciated woman with concomitant medical illness but without previous abdominal surgery, presenting with intestinal obstruction, which conforms to the pattern reported in the previous reviews.2-RWomen were more commonly affected by this rare hernia than men (7: 1) (6:l in a review of 50 patients5). All our female patients were over 70 years of age, with a mean age of 80.5 years. There were only two men in our series, and they were younger: 63 and 74 years of age. In our experience, patients are emaciated on admission. Their mean body weight was only 39.5 kg. However, another factor, that of recent loss of body weight, was difficult to elicit objectively in the history. The average patient had more than one medical illness on admission. Most of them were residents of nursing homes or had been trans-
THE AMERICAN
JOURNAL
OF SURGERY
VOLUME
167
APRIL 1994
397
LO ETAL
ferred from chronic hospitals while undergoing treatment for other medical conditions. Concomitant medical illnesses including chronic obstructive pulmonary disease, congestive heart failure, and cirrhosis appear to be predisposing factors. It is believed that women with a wider pelvis and more oblique obturator canal’ are predisposed to the development of obturator hernia in the presence of decreased preperitoneal fat due to emaciation and also chronic increased intra-abdominal pressure due to medical diseases.3 This may account for the relatively high incidence in our Chinese population as a larger proportion of our population is thin compared with the Western standard. Intestinal obstruction, Howship-Romberg sign, and a mass in the groin were reported to occur in 88%, 48%, and 19%, respectively, in one review.5 However, in our series, the only reliable preoperative findings were physical signs and abdominal roentgenograms consistent with small bowel obstruction in a previously unexplored abdomen. Symptoms consistent with a positive Howship-Romberg sign were present in only two patients. A correct preoperative diagnosis was suspected in 38% of patients, whereas the rate of correct preoperative diagnosis ranged from 21.5% to 31.3% in other reviews.1*4*5 The reason for the delay in operation from less than 24 hours to 6 days was attributed to various factors: poor condition of patients on admission, which necessitated stabilization; reluctance of the surgeon to operate because of the advanced age of the patient, and the presence of partial or intermittent obstruction. Some authors have mentioned the use of computed tomographic scan,’ electromyography, obturator nerve blocks,3 and the absence of adductor reflex,‘O but none of these were used in our patients. A variety of intra-abdominal structures including the colon, appendix, Meckel’s diverticulum, omentum, bladder, ovary, uterus, fallopian tube,’ and foci of endometriosis3 has been reported in various reviews, but the hernial sac content in all our patients was obstructed small bowel. Kwong and 0ng8 in our institution previously reported on six patients with obturator hernia, and all of the patients presented with small bowel obstruction. In a review of 50 cases,5 small bowel accounted for 88% of stmngulated obturator hernia. The rate of resection of gangrenous bowel with or without perforation was 80% in our series, which was comparable to the rate of 25% to 100% reported in other reviews. I1 The predominance of rightsided involvement (R:L = 105) corresponds to previous reports, whereas bilateral involvement is extremely rare (right:left:bilateral = 33: 16:1 in a review of 50 patient$). Various approaches and the repair of the obturator orifices have been recommended.2-8 The i&a-abdominal approach, usually through a lower mid-line, remains the best for this group of patients l2 because it establishes the diagnosis and affords the advantages of exposure for gut resection, which is so common in our series (80%). The necessity of repair of the obturator defect after reduction is still debatable in this group of high-risk patients. In the
398
a great variety of techniques have been used for closure of the defect, and many of these, including plugging the canal with cartilage or with free omentum, use of osteoperiosteal flap, tantalum gauze, peritoneal flap, teflon cloth,* and bladder flapI are relatively difficult and time consuming. The rate of recurrence in unclosed defects has been estimated to be lo%.‘* In a review of 50 patients, the treatment included no repair (n = 14), closure of defect (n = 24), excision of sac (n = 5), and excision of sac with closure of defect (n = 7).5 Recmrence occurred in 1 of the 19 unclosed defects.5 One author suggested that simple interrupted stitches to narrow the defect was likely to be equally effective and much faster in smaller defects.* This method was used in 12 of our patients, whereas the hernial orifice was left untouched in the remaining patients (25%). Our patients have been followed up for a mean period of 9.4 months (range: 1 to 27 months), and recurrence has not so far been encountered in our patients. Reported mortality for obturator hernia with acute intestinal obstruction has been traditionally high. These high figures have been attributed to the debilitated condition of these elderly patients with multiple medical problems who presented late with a elusive diagnosis. Our overall mortality rate of 38% does not differ significantly from other reported series (10% to 50%).*-* past,
This may well prove to be the dejnitive modem paper on obturator hernia from one of the world’s most respected academic surgical centers. Rare causes of intestinal obstruction deserve emphasis since this is a disease of the elderly in an ever aging world.
REFERENCES 1. Watson LF. Hernia: anatomy, etiology, symptoms, diagnosis, differential diagnosis, prognosis and treatment. 3rd ed. St. Louis: C.V. Mosby Company, 1948:457475. 2. Rogers FA. Strangulated obturator hernia Surgery. 1%0,48:394-403. 3. Bjork KJ, Mucha P Jr, Cahil DR. Obturator hernia. Surg Gynecol Obstet. 1988;167:217-222. 4. Sinha SN, DeCosta AE. Obturator hernia. Aust N Z J Surg. 1983;53:349-351. 5. Gray SW, Skandalakis JF, Soria RE, Rowe JS. Strangulated obturator hernia. Surgery. 1974;75:20-27. 6. Harper JR, Holt JH. Obturator hernia. Am JSurg. 1956;92:562-565. 7. Kozlowski JM, Beal JM. Obturator hernia: an elusive diagnosis. Arch Surg. 1977;112:1001-1002. 8. Kwong KH, Ong GB. Obturator hernia. Br JSurg. 1966;53:23-25. 9. Cubillo E. Obturator hernia diagnosed by computed tomography. Am J Roentgenol. 1983;140:735-736. 10. Hannington-Kiff JG. Absent thigh adductor reflex in obturator hernia. Luncet. 1980; 1: 180. 11. Rimmer JA, Wharton S, Smedley FH, Horsburgh AG. Bilateral and recurrent obturator hernia. Br J Clin Pratt. 1990;44:784. 12. Shackleford RT. Surgery of the alimentary tract. Philadelphia: W.B. Saunders Company, 1955:2369-2377. 13. Arbman G. Strangulated obturator hernia. A simple method for closure. Acta Chir Scand. 1984;150:337-339.
THE AMERICAN JOURNAL OF SURGERY VOLUME 167 APRIL 1994
Obturator hernia is a rare but important cause of small bowel obstruction that is associated with difficult diagnosis and high mortality. In the past 7 years, 16 patients with small bowel obstruction due to obturator hernia diagnosed at operation were seen at the Department of Surgery, the University of Hong Kong, Queen Mary Hospital. They represented 1% (16 of 1,554) of all hernia repair performed and 1.6% (16 of 1,000) of mechanical intestinal obstruction encountered during the same period.’ Elderly emaciated women with chronic disease were commonly affected. All patients presented with partial or complete mechanical small bowel obstruction. R@bt-sided obturator hernia outnumbered left-sided hernia, and bilateral hernia was found in only one patient. The majority of patients required resection of their strangulated small bowel. Most of the hernial orifices were closed with interrupted nonabsorbable sutures. Morbidity and mortality rates were significantly high for this group of debilitated patients with chronic disease who underwent late operation for tbis elusive diagnosis.
0
bturator hernia is an uncommon but important cause of intestinal obstruction because of its difficult diagnosis and high mortality rate. The condition was first described in 1724 by Arnaud de Ronsil of France.’ It remains a rare condition for which a variety of case reports and small series have appeared in the literature. One of the largest series, consisting of 12 cases of strangulated obturator hernia, was reported by Rogers in 1960.* By 1980, Bjork and associates3 and Sinha and DeCosta4 had collected 541 cases of obturator hernia that had been reported in the English language. Despite all these reports, intestinal obstruction due to obturator hernia remains an elusive diagnosis often made only at laparotomy. In a search of the English literature from 1980 to 1992, we have collected 43 more cases of obturator hernia, which, in addition to the 16 cases we report here, brings the total to 600. The aim of the present study is to report our own experience and to compare this with the previous reports.
From the Department of Surgery, The University of Hong Kong Queen Mary Hospital, Hong Kong. Requests for reprints should be addressed to Dr. Chung Yau Lo, Department of Surgery, The University of Hong Kong, Queen Mary Hospital, Pokulam Road, Hong Kong. Manuscript received October 27, 1992, and accepted in revised form March 8, 1993.
396
THE AMERICAN
JOURNAL
OF SURGERY
VOLUME
167
TABLE I Concomitant Medical Pathologies Medical Patholorries Chronic obstructive pulmonary disease Congestive heart failure lschaemic heart disease Cardiac arrhythmia Hypertension Cirrhosis Diabetes mellitus Tuberculosis or pneumonia Cerebrovascular accident Total (No. of patients)
No. 6 3 3 3 2 2 1 3 1 24 (10)
I
PATIENTS AND METHODS From January 1985 to March 1992, 16 Chinese patients with small bowel obstruction due to obturator hernia diagnosed at operation were seen at the Department of Surgery, the University of Hong Kong, Queen Mary Hospital. Their clinical records were reviewed retrospectively with respect to age, sex, body weight on admission, previous medical illness, clinical presentation, operative findings, treatment received, postoperative outcome, and follow-up. In addition, the number of patients with mechanical intestinal obstruction due to other causes that we encountered and the number of hernia operations we performed during the same period were documented so as to evaluate the relative importance of this condition. RESULTS Patientcharacteristics and clinicalpresentation:There were 14 women and 2 men, for a female-to-male ratio of 7 to 1. The age range was 63 to 97 years, with a mean age of 79 years. Body weight on admission ranged from 30 to 45 kg, with a mean of 39.5 kg. Each patient had an average of 1.5 concomitant medical problems on admission (Table I). All thepatients presented with intestinal obstruction. The presenting symptoms were abdominal pain, vomiting, and abdominal distension. All 16 patients had at least 1 of these symptoms, and 12 patients had all 3 symptoms on admission. Two of them were actually admitted with coffee ground vomitus, which was initially thought to be due to upper gastrointestinal tract bleeding, whereas one patient was admitted with frank generalized peritonitis due to strangulated small bowel with perforation. Only one quarter of-the~patients recalled a past history of a similar attack, within 1 month prior to admission, which resolved spontaneously. The interval between presentation and admission to hospital was 3 days (range: less than 24 hours to 2 weeks). Five patients came from nursing homes,
APRIL 1994
TABLE II
1
TABLE III Operative Findings J!?ua Right Left
Complications
Jeiunum Right Left
Perforated Gangrenous Perforated on reduction Incarcerated
1 4 1 2
2
2’
1
-
1
1’
Total
8
4
3
2
1 1
‘One patient had bilateral involvement.
Morbidity and Mortality No.
Cardiac arrhythmia Congestive heart failure Pneumonia Pneumothorax Gastrointestinal bleeding Wound infection Sepsis
3 1 7 2 1 2 1
Total’
17
Mortality
5
1 6
*Some patients had more than one complication.
whereas two patients were actually transferred from other chronic convalescent hospitals for treatment of other medical conditions. Physical examination on admission in all 16 patients revealed a distended abdomen with high-pitched bowel sounds. Four patients had clinical evidence of local or generalized peritonitis. None of the patients had undergone previous abdominal surgery. Howship-Romberg sign, which refers to ipsilateral groin pain radiating down to the thigh due to irritation of the obturator nerve, was present in only two of the patients. An erect and supine plain abdominal radiograph revealed dilated small bowel loops with multiple air-fluid levels in all 16 patients. The correct diagnosis was suspected preoperatively in six (38%) patients on the basis of the characteristic clinical setting. Despite this, due to a number of factors, the delay between admission and surgery was an average of 3 days (range: less than 24 hours to 6 days). Operative findings and management: Laparotomy was performed through a lower mid-line incision in all the patients. Right-sided obturator hernia outnumbered left-sided hernia (R:L = 10:.5),and bilateral hernia was rare (n = 1). All the patients had small bowel involvement in the hernial sac and evidence of complete or partial small bowel obstruction with proximal dilated and distal collapsed small bowel. The segment of small bowel involved was the ileum in 12 and the jejunum in 5, for a total of 17 hernias (Table II). Nine of these were of the Richter’s type. Reduction of incarcerated small bowel without resection was performed in 3 patients, whereas resection of small bowel was performed in 13 patients who had gangrenous bowel with (n = 6) or without (n = 6) perforation, or nonviable bowel that perforated on reduction (n = 2). The one patient with bilateral involvement had gangrenous Richter’s type of herniation of jejunum on both sides with perforation on the right side. Thirteen hernial orifices in 12 patients were closed by multiple interrupted nonabsorbable sutures, whereas the hernial orifice itself was not treated in 4 patients. The mean estimated blood loss was 180 mL (20 to 500 rnL), whereas the mean operative time was 80 minutes (30 minutes to 2 hours). Morbidity and mortality: Half of this group of poor-risk patients required postoperative ventilation. Four patients died within 30 days after operation resulting in an operative mortality of 25%. Three of them died of postoperative bronchopneumonia, and a 97-year-old woman died of sepsis. Two more patients died during their stay in our con-
_I
valescence hospital on postoperative day 44 and 48, respectively, due to exacerbation of their chronic obstructive pulmonary disease with development of bronchopneumonia, resulting in a hospital mortality of 38%. Seventeen postoperative complications occurred among 10 (63%) patients (Table III). The mean hospital stay was 18 days (range: 6 to 50 days). Follow-up: The surviving 10 patients have been followed up from 1 to 27 months (mean: 9.4 months) without any recurrent obstruction or symptoms due to recurrent hemiation. One patient was readmitted 7 months after the operation with small bowel perforation related to an adhesion band. Emergency laparotomy with small bowel resection was again performed, but the patient died 6 days after the operation because of septicemia. COMMENTS A group of 16 patients with obturator hernia presenting with small bowel obstruction diagnosed at operation was encountered in our department during the past 7 years. They represented 1% of the 1,554 hernia operations performed during this period, which is much higher than that reported by Bjork and associates (0.073%).3 Rogers2 reported 12 cases of obturator hernia among 3,000 patients with mechanical intestinal obstruction treated at the Los Angeles County General Hospital (0.4%). In our series, we found 16 cases of obturator hernia among 1,000 patients with mechanical intestinal obstruction within the same period (1.6%). These figures suggest a higher incidence of obturator hernia in our Chinese population. The characteristic clinical profile of our patients was that of an elderly, emaciated woman with concomitant medical illness but without previous abdominal surgery, presenting with intestinal obstruction, which conforms to the pattern reported in the previous reviews.2-RWomen were more commonly affected by this rare hernia than men (7: 1) (6:l in a review of 50 patients5). All our female patients were over 70 years of age, with a mean age of 80.5 years. There were only two men in our series, and they were younger: 63 and 74 years of age. In our experience, patients are emaciated on admission. Their mean body weight was only 39.5 kg. However, another factor, that of recent loss of body weight, was difficult to elicit objectively in the history. The average patient had more than one medical illness on admission. Most of them were residents of nursing homes or had been trans-
THE AMERICAN
JOURNAL
OF SURGERY
VOLUME
167
APRIL 1994
397
LO ETAL
ferred from chronic hospitals while undergoing treatment for other medical conditions. Concomitant medical illnesses including chronic obstructive pulmonary disease, congestive heart failure, and cirrhosis appear to be predisposing factors. It is believed that women with a wider pelvis and more oblique obturator canal’ are predisposed to the development of obturator hernia in the presence of decreased preperitoneal fat due to emaciation and also chronic increased intra-abdominal pressure due to medical diseases.3 This may account for the relatively high incidence in our Chinese population as a larger proportion of our population is thin compared with the Western standard. Intestinal obstruction, Howship-Romberg sign, and a mass in the groin were reported to occur in 88%, 48%, and 19%, respectively, in one review.5 However, in our series, the only reliable preoperative findings were physical signs and abdominal roentgenograms consistent with small bowel obstruction in a previously unexplored abdomen. Symptoms consistent with a positive Howship-Romberg sign were present in only two patients. A correct preoperative diagnosis was suspected in 38% of patients, whereas the rate of correct preoperative diagnosis ranged from 21.5% to 31.3% in other reviews.1*4*5 The reason for the delay in operation from less than 24 hours to 6 days was attributed to various factors: poor condition of patients on admission, which necessitated stabilization; reluctance of the surgeon to operate because of the advanced age of the patient, and the presence of partial or intermittent obstruction. Some authors have mentioned the use of computed tomographic scan,’ electromyography, obturator nerve blocks,3 and the absence of adductor reflex,‘O but none of these were used in our patients. A variety of intra-abdominal structures including the colon, appendix, Meckel’s diverticulum, omentum, bladder, ovary, uterus, fallopian tube,’ and foci of endometriosis3 has been reported in various reviews, but the hernial sac content in all our patients was obstructed small bowel. Kwong and 0ng8 in our institution previously reported on six patients with obturator hernia, and all of the patients presented with small bowel obstruction. In a review of 50 cases,5 small bowel accounted for 88% of stmngulated obturator hernia. The rate of resection of gangrenous bowel with or without perforation was 80% in our series, which was comparable to the rate of 25% to 100% reported in other reviews. I1 The predominance of rightsided involvement (R:L = 105) corresponds to previous reports, whereas bilateral involvement is extremely rare (right:left:bilateral = 33: 16:1 in a review of 50 patient$). Various approaches and the repair of the obturator orifices have been recommended.2-8 The i&a-abdominal approach, usually through a lower mid-line, remains the best for this group of patients l2 because it establishes the diagnosis and affords the advantages of exposure for gut resection, which is so common in our series (80%). The necessity of repair of the obturator defect after reduction is still debatable in this group of high-risk patients. In the
398
a great variety of techniques have been used for closure of the defect, and many of these, including plugging the canal with cartilage or with free omentum, use of osteoperiosteal flap, tantalum gauze, peritoneal flap, teflon cloth,* and bladder flapI are relatively difficult and time consuming. The rate of recurrence in unclosed defects has been estimated to be lo%.‘* In a review of 50 patients, the treatment included no repair (n = 14), closure of defect (n = 24), excision of sac (n = 5), and excision of sac with closure of defect (n = 7).5 Recmrence occurred in 1 of the 19 unclosed defects.5 One author suggested that simple interrupted stitches to narrow the defect was likely to be equally effective and much faster in smaller defects.* This method was used in 12 of our patients, whereas the hernial orifice was left untouched in the remaining patients (25%). Our patients have been followed up for a mean period of 9.4 months (range: 1 to 27 months), and recurrence has not so far been encountered in our patients. Reported mortality for obturator hernia with acute intestinal obstruction has been traditionally high. These high figures have been attributed to the debilitated condition of these elderly patients with multiple medical problems who presented late with a elusive diagnosis. Our overall mortality rate of 38% does not differ significantly from other reported series (10% to 50%).*-* past,
This may well prove to be the dejnitive modem paper on obturator hernia from one of the world’s most respected academic surgical centers. Rare causes of intestinal obstruction deserve emphasis since this is a disease of the elderly in an ever aging world.
REFERENCES 1. Watson LF. Hernia: anatomy, etiology, symptoms, diagnosis, differential diagnosis, prognosis and treatment. 3rd ed. St. Louis: C.V. Mosby Company, 1948:457475. 2. Rogers FA. Strangulated obturator hernia Surgery. 1%0,48:394-403. 3. Bjork KJ, Mucha P Jr, Cahil DR. Obturator hernia. Surg Gynecol Obstet. 1988;167:217-222. 4. Sinha SN, DeCosta AE. Obturator hernia. Aust N Z J Surg. 1983;53:349-351. 5. Gray SW, Skandalakis JF, Soria RE, Rowe JS. Strangulated obturator hernia. Surgery. 1974;75:20-27. 6. Harper JR, Holt JH. Obturator hernia. Am JSurg. 1956;92:562-565. 7. Kozlowski JM, Beal JM. Obturator hernia: an elusive diagnosis. Arch Surg. 1977;112:1001-1002. 8. Kwong KH, Ong GB. Obturator hernia. Br JSurg. 1966;53:23-25. 9. Cubillo E. Obturator hernia diagnosed by computed tomography. Am J Roentgenol. 1983;140:735-736. 10. Hannington-Kiff JG. Absent thigh adductor reflex in obturator hernia. Luncet. 1980; 1: 180. 11. Rimmer JA, Wharton S, Smedley FH, Horsburgh AG. Bilateral and recurrent obturator hernia. Br J Clin Pratt. 1990;44:784. 12. Shackleford RT. Surgery of the alimentary tract. Philadelphia: W.B. Saunders Company, 1955:2369-2377. 13. Arbman G. Strangulated obturator hernia. A simple method for closure. Acta Chir Scand. 1984;150:337-339.
THE AMERICAN JOURNAL OF SURGERY VOLUME 167 APRIL 1994