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Femoral nerve injury associated with the Pfannenstiel incision and abdominal retractors
Femoraf nerve injury associated with the Pfannenstiel incision and abdominal retractors GROVER C. McDANIEL, M.D. WILLIAM H. KIRKLEY, M.D. ]. C. GILBERT, M.D Fort Lauderdale, Florida
T R Au M A to. the femoral nerve at the time of pelvic surgery has received scant attention in the medical literature. Winkelman, 1 Johnson and Montgomery/ and Ruston and Politi3 have each recently reported cases of femoral nerve complications which they attributed to intrapelvic pressure from retractors. The definitive article on the subject has been written by Vosburgh and Finn4 who reported 9 cases. The three factors common to most of their patients who sustained a nerve injury were: ( 1) the transverse, muscle-retracting suprasymphysial inCisiOn of the Pfannenstiel type, (2) the use of a self-retaining retractor, and ( 3) the body build of the patient. They put rather definite emphasis on a specific type of self-retaining retractor which had been used in each of their cases. Our three cases seem to confirm the etiological factors previously mentioned.
formed in May, 1959, for extensive endometriosis. The operation was performed through a transverse, muscle-retracting, suprasymphysial incision of the Pfannenstiel type, under pentothal sodium cyclopropane, and d-tubocurarinc anesthesia. A Balfour self-retaining retractor was used during the procedure. On the first postoperative day, the patient complained of numbness and weakness of the right leg. On the second postoperative day she collapsed when attempting to stand. A neurological consultant suggested a diagnosis of partial right femoral nerve paralysis characterized by weakness of the quadriceps muscle, absent knee jerk, and minimal sensory loss. Crutches were necessary for only 2 days because of very rapid improvement in the strength of the right leg. The patient was discharged from the hospital on the seventh postoperative day, with only slight weakness of the right leg. Six weeks following the operation, the patient experienced slight numbness and weakness above the right knee, particularly noticeable when she attempted to run. Twelve weeks postoperatively, the woman had minimal complaints of the leg. Forty-four months following surgery, she was asymptomatic with excellent functional US(' of her leg. Neurological examination was normal. Case 2. Mrs. J. B., a 37-year-old multipara, weight 125 pounds, height 5 feet, 5 inches, had a total abdominal hysterectomy and bilateral salpingo-oophorectomy in April, 1960, for extensive endometriosis. The operation was performed through a Pfannenstiel incision under bromochlorotrifluoroethane and nitrous oxide anesthesia. A Balfour st>lf-rctaining f('tractor was
Case reports Case 1. Mrs. F. C., a 36-year-old multipara, weight 119 pounds, height 5 feet, 2 inches, had a total abdominal hysterectomy, bilateral salpingo-oophorectomy, and appendectomy per-
From the Department of Obstetrics and Gynecology, Broward General Hospital. Presented by invitation at the Twentyfifth Annual Meeting of the South Atlantic Association of Obstetricians and Gynecologists, Hot Springs. Virginia, Feb. 3-6, ]963.
381
382
McDaniel, Kirkley, and Gilbert
used. Five hundred milliliters of whole blood were given immediately postoperatively for mild shock. On the first postoperative day, the subject complained of weakness and numbness of the right leg. She collapsed on attempting to stand. Neurological examination showed marked weakness of the right quadriceps femoris muscle and decreased sensation over the sensory distribution of the right femoral nerve. The right knee jerk was absent. The neurological diagnosis was right femoral nerve paralysis probably secondary to pressure. The prognosis was considered to be good in view of the incompleteness of the nerve lesion. During the 10 postoperative days, the patient continued to have weakness of the right leg, but by the seventh postoperative day she was able to walk without assistance. Six weeks postoperatively, the patient was asymptomatic. Neurological evaluation 32 months following surgery was normal. Case 3. Mrs. C. E., a 46-year-old multipara had an uneventful menopause at aged 41. In January, 1959, she was successfully treated for cirrhosis of the liver probably secondary to hepatitis. She had had no vaginal bleeding fo r 5 years until 2 months prior to currettage on May 13, 1960. This disclosed adenocarcinoma of the endometrium. Clinically, this adenocarcinoma seemed early with a small uterus and negative adnexa. On May 19, 1960, an Ernst
October I, !96:l Am. J, Obst. & Gynec.
applicator was inserted to administer 4,200 mg.hr. of intracavitary and paracervical radium. On June 21, 1960, her weight was 110 pounds and height 5 feet, 6 inches. Liver fun ction tests were normal. On June 22, 1960, a total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed under thiopental sodium, nitrous oxide, and bromochlorotrifluorocthane anesthesia. The operation was performed through a Pfannenstiel incision. The physician remembered adjusting and respreading the Balfour selfretaining retractor several times during the operation in an effort to improve exposure. Pathological examination showed no residual tumor in the uterus. A I em. cyst of the right ovary was lined with a single layer of neoplastic cells, which were considered to be metastatic from the uterus. The remainder of the pathological examination was negative. Between July 6, and Aug. 11, 1960, deep x-ray therapy for a total dose of 2,400 r in air to each of four external ports cross-firing the adnexal regions of the pelvis was administered. The entire postoperative course was complicated by a chronic low-grade infection of the pelvis and abdominal incision. On the second postoperative day the left leg buckled and the patient collapsed when attempting to stand. Numbness of the left thigh was noted. Neurological examinati on disclosed de-
Fig. I. Diagrammatic representation showing the relationship between the late ral blades of the retractor and the femoral nerve. Anteroposterior projection.
Volume 87 Number 3
creased sensation over the anterior and medial aspect of the left thigh from the groin to the knee, i.e., over the sensory distribution of the left femoral nerve. There was marked inability to extend the left leg at the knee and no left knee jerk could be obtained. The neurological diagnosis was paralysis of the left femoral nerve with almost complete impairment of the motor function. Sensation was only partially impaired. The consultant suggested that the lesion was caused by pressure on the femoral nerve at the lime of operation and since the lesion was incomplete, eventual restoration of function seemed likely. Physiotherapy was begun and ambulation was possible with the aid of a walker. Immediately prior to discharge she was fitted with a knee brace and crutches which permitted greater freedom of movement. The patient was discharged from the hospital on the thirty-sixth postoperative day, with minimal return of function of the left leg. Neurosurgical consultation was obtained during the latter days of her hospital stay, but a continued program of conservative therapy was advised and no serious consideration was given to any surgical approach to the femoral nerve. Four months following the operation, the patient stated that her leg was much stronger and that she could walk unaided. However, at this time, the left patella was completely mobile on examination. Six months postoperatively, the woman was able to run, swim, and work as a practical nurse. Neurological examination eleven months following surgery disclosed slight wasting of the left quadriceps femoris muscle. The left knee jerk was markedly diminished although the reflex was now present whereas it had been absent previously. From a functional viewpoint, the patient's leg continued to perform very satisfactorily until her death on July 7, 1962, 2 years after the initial operation. Autopsy gave no evidence of tumor in the pelvis, but a 16 em. retroperitoneal mass of metastatic adenocarcinoma posterior to the cirrhotic liver and stomach was noted. Detailed gross and microscopic examination of both femoral nerves failed to show any abnormality. The left midthigh measured 4 em. smaller than the right midthigh. Comment
The femoral nerve is the largest branch of the lumbar plexus. It courses downward,
Femoral nerve injury and Pfannenstiel incision
383
passing through the psoas major muscle, then between the psoas and iliacus muscles, entering the thigh lateral to the femoral canal at the midpoint between the anterior superior iliac spine and the pubic tubercle. Constant pressure from the lateral blades of the self-retaining retractor can be exerted on the psoas major muscle and femoral nerve approximately 4 em. proximal to its point of entry into the thigh. The Pfannenstiel incision allows the lateral blades of the retractor to be placed in more intimate contact with the lateral pelvic walls, and therefore with the femoral nerves, than other incisions might permit. A long Pfannenstiel incision would obviously allow more lateral placement of the retractor blades than would a short incision. Routinely the bladder blade of the self-retaining retractor is inserted superiorly, thus increasing the lateral and downward pressure in the area of the femoral nerve. Our third patient, who was the most severely affected, exemplifies the relationship of the woman with a thin abdominal wall to the injury. The thin abdominal wall permits deeper and more lateral placement of the retractor blades. The main muscle that the femoral nerve supplies is the quadriceps femoris. The sensory portion of the nerve supplies the anterior and medial surface of the thigh and leg. In the more advanced lesions, the patient nearly always complains of numbness of the anterior thigh and inability to extend the leg at the knee. On first attempting to stand or walk, the subject usually falls. Each of our three patients collapsed when attempting to stand. Rather simple examination will demonstrate definite weakness of the quadriceps muscle as well as a markedly decreased or absent knee jerk. When the quadriceps muscle contracts, the patella on the weakened leg can be freely moved in many directions. The patella of the uninvolved leg obviously is stable during a similar examination. Careful examination will also demonstrate the sensory loss. Probably many cases that occur are quite mild, the patient experiencing only a
384
Oclolw1 I, l9b:l
McDaniel, Kirkley, and Gilbert
vague weakness in the leg. This weakness spontaneously improves over a period of weeks without ever being detected by the physician. Although bilateral involvement has not been reported, it is certainly possible and could constitute a very serious problem in that the patient would be unable to walk: standing might even be difficult. The management of all the reported cases has been conservative with the use of physiotherapy, knee braces and primarily, time to allow maximum return of nerve function. Fortunately, in most cases reported, the return of function was relatively rapid ( 1 to 24 weeks). Good functional results are undoubtedly attributable to the relatively simple mass functions performed by the muscles innervated by the femoral nerve and to the lack of importance in the thigh of the discriminatory sensation in the areas suppEed by this nerve. o. •> ..t\lthough spontaneous recovery is the rule, recovery is not always spontaneous or complete. Surgical intervention to explore and repair the nerve should be considered if some degree of recovery cannot be den1onstrated after an interval of
three months following the nerve injury." Prevention
By far the most important aspect of this problem involves prevention. Vosburgh and Finn indict a specific type of circular, selfretaining retractor with two solid curved lateral blades. They state that by eliminating this specific retractor, they have encountered no further difficulty with femoral nerve trauma. Winkelman, Johnson, and Montgomery failed to state the types of retractors that were used. We feel that any retractor, particularly a self-retaining retractor, may exert pressure and cause trauma. One of the most important measures of prevention is more careful placement of the lateral blades of the retractor with insertion of a large folded laparotomy pad under each blade to REFERENCES
1. Winkelman, N. W.: AM.
75: 1063. 1958.
J.
0BsT. & Gv;-,;Ec.
:\m.
J. Ohst.
& f;yw·c
cushion and protect the lateral pelvic wall. If a Balfour retractor is selected, the smallest lateral blades should always be used. Sorm' thought should be given to placement of the bladder blade of the Balfour retractor over the symphysis in an effort to decrease downward and lateral pressure in the femoral nerve area.' Placement of the bladder blade in this position would decrease exposure however. The Pfannenstiel incision should not be extended laterally more than is needed to perform the necessary operation because the wider the incision, the greater the likelihood of the retractor exerting pressure in the area of the femoral nerve. Certainly greater care must be taken in the person with the thin anterior abdominal wall. The importance of the underlying disease, nutrition, vitamin deficiencies, radiation, and infection in the pathogenesis of this disorder is not clear. It seems reasonable that these
factors could contribute to the severity of the lesion and the time necessary for recm:ery to occur. We are still frequently using the Pfannenstiel incision and the self-retaining retractor but by following the methods of prevention mentioned, especially the careful cushioning of the lateral retractor blades with a large laparotomy pad, we have had no additional cases of nerve trauma. Summary
1. Three cases of femoral nerve injury with quadriceps femoris paralysis associated with the Pfannenstiel incision and the use of a self-retaining retractor are presented. Autopsy findings are reported in one case. 2. Pressure on the nerve by the lateral retractor blade appears to be the cause of the injury. :1. Conservative management resulted in a functional recovery for all 3 patients. 4. Prevention is the most important aspect of this problem.
2. Johnson, D. A., and Montgomery, R. D.: M. Ann. District of Columbia 27: 513, 1958.
Volume 87 Number :1
3. Ruston, F. G., and Politi, V. L.: Canad. Anaesth. Soc. J. 5: 428, 1958. 4. Vosburgh, L. F., and Finn, W. F.: AM. J. OasT. & Gnmc. 82: 931, 1961. 5. Clare, F. B.: J. Neurosurg. 13: 195, 1956.
Discussion DR. }EsSE CALDWELL, Gastonia, North Carolina. We have heard reported 3 instances of an injury which is easily produced and is no doubt more frequent than is generally known. The responsibility of calling attention to complications resulting from the use of certain procedures or instruments rightfully belongs to the medical profession. It is hoped that public behavior resulting from social and economic trends will not prevent adequate dissemination of such information in the years to come. In addition to those factors mentioned by the authors as being necessary for the occurrence of a femoral nerve injury, another one, the length of operating time, may be considered. In these reported cases, in which an abdominal hysterectomy was performed, the length of operating time would be of interest. Observation may indicate that nerve injuries due to pressure may be rare in procedures of shorter duration. The authors continue to use the transverse in-
Femoral nerve injury and Pfannenstiel incision
385
6. Wen,tworth, Alan, Bell, H. S., and Clare, F. B.: J. A. M. A. 176: 447, 1961. 7. Vosburgh, L. F.: Personal communication. 3025 W. Broward Blvd. Fort Lauderdale, Florida
cision for abdominal-pelvic surgery, but take adequate precautions to prevent trauma to thr abdominal portion of the femoral nerves. Vosburgh and Finn have discontinued the use of a circular self-retaining retractor they found objectionable. The transverse incision and the adjustable circular retractor do offer superior advantages in approach to the pelvis and if at all possible it seems desirable that their use be continued. A technique in the adjustment of the circular self-retaining retractor and the placement of padding under the lateral blades seem to give adequate protection to the femoral nerve as it lies exposed on the wing of the ilium between the psoas major and iliacus muscles near the inguinal ligament. Perhaps in the future the instrument manufacturer will make retractors with shorter lateral blades for use in patients who are slender and have thinner abdominal walls.
T R Au M A to. the femoral nerve at the time of pelvic surgery has received scant attention in the medical literature. Winkelman, 1 Johnson and Montgomery/ and Ruston and Politi3 have each recently reported cases of femoral nerve complications which they attributed to intrapelvic pressure from retractors. The definitive article on the subject has been written by Vosburgh and Finn4 who reported 9 cases. The three factors common to most of their patients who sustained a nerve injury were: ( 1) the transverse, muscle-retracting suprasymphysial inCisiOn of the Pfannenstiel type, (2) the use of a self-retaining retractor, and ( 3) the body build of the patient. They put rather definite emphasis on a specific type of self-retaining retractor which had been used in each of their cases. Our three cases seem to confirm the etiological factors previously mentioned.
formed in May, 1959, for extensive endometriosis. The operation was performed through a transverse, muscle-retracting, suprasymphysial incision of the Pfannenstiel type, under pentothal sodium cyclopropane, and d-tubocurarinc anesthesia. A Balfour self-retaining retractor was used during the procedure. On the first postoperative day, the patient complained of numbness and weakness of the right leg. On the second postoperative day she collapsed when attempting to stand. A neurological consultant suggested a diagnosis of partial right femoral nerve paralysis characterized by weakness of the quadriceps muscle, absent knee jerk, and minimal sensory loss. Crutches were necessary for only 2 days because of very rapid improvement in the strength of the right leg. The patient was discharged from the hospital on the seventh postoperative day, with only slight weakness of the right leg. Six weeks following the operation, the patient experienced slight numbness and weakness above the right knee, particularly noticeable when she attempted to run. Twelve weeks postoperatively, the woman had minimal complaints of the leg. Forty-four months following surgery, she was asymptomatic with excellent functional US(' of her leg. Neurological examination was normal. Case 2. Mrs. J. B., a 37-year-old multipara, weight 125 pounds, height 5 feet, 5 inches, had a total abdominal hysterectomy and bilateral salpingo-oophorectomy in April, 1960, for extensive endometriosis. The operation was performed through a Pfannenstiel incision under bromochlorotrifluoroethane and nitrous oxide anesthesia. A Balfour st>lf-rctaining f('tractor was
Case reports Case 1. Mrs. F. C., a 36-year-old multipara, weight 119 pounds, height 5 feet, 2 inches, had a total abdominal hysterectomy, bilateral salpingo-oophorectomy, and appendectomy per-
From the Department of Obstetrics and Gynecology, Broward General Hospital. Presented by invitation at the Twentyfifth Annual Meeting of the South Atlantic Association of Obstetricians and Gynecologists, Hot Springs. Virginia, Feb. 3-6, ]963.
381
382
McDaniel, Kirkley, and Gilbert
used. Five hundred milliliters of whole blood were given immediately postoperatively for mild shock. On the first postoperative day, the subject complained of weakness and numbness of the right leg. She collapsed on attempting to stand. Neurological examination showed marked weakness of the right quadriceps femoris muscle and decreased sensation over the sensory distribution of the right femoral nerve. The right knee jerk was absent. The neurological diagnosis was right femoral nerve paralysis probably secondary to pressure. The prognosis was considered to be good in view of the incompleteness of the nerve lesion. During the 10 postoperative days, the patient continued to have weakness of the right leg, but by the seventh postoperative day she was able to walk without assistance. Six weeks postoperatively, the patient was asymptomatic. Neurological evaluation 32 months following surgery was normal. Case 3. Mrs. C. E., a 46-year-old multipara had an uneventful menopause at aged 41. In January, 1959, she was successfully treated for cirrhosis of the liver probably secondary to hepatitis. She had had no vaginal bleeding fo r 5 years until 2 months prior to currettage on May 13, 1960. This disclosed adenocarcinoma of the endometrium. Clinically, this adenocarcinoma seemed early with a small uterus and negative adnexa. On May 19, 1960, an Ernst
October I, !96:l Am. J, Obst. & Gynec.
applicator was inserted to administer 4,200 mg.hr. of intracavitary and paracervical radium. On June 21, 1960, her weight was 110 pounds and height 5 feet, 6 inches. Liver fun ction tests were normal. On June 22, 1960, a total abdominal hysterectomy and bilateral salpingo-oophorectomy were performed under thiopental sodium, nitrous oxide, and bromochlorotrifluorocthane anesthesia. The operation was performed through a Pfannenstiel incision. The physician remembered adjusting and respreading the Balfour selfretaining retractor several times during the operation in an effort to improve exposure. Pathological examination showed no residual tumor in the uterus. A I em. cyst of the right ovary was lined with a single layer of neoplastic cells, which were considered to be metastatic from the uterus. The remainder of the pathological examination was negative. Between July 6, and Aug. 11, 1960, deep x-ray therapy for a total dose of 2,400 r in air to each of four external ports cross-firing the adnexal regions of the pelvis was administered. The entire postoperative course was complicated by a chronic low-grade infection of the pelvis and abdominal incision. On the second postoperative day the left leg buckled and the patient collapsed when attempting to stand. Numbness of the left thigh was noted. Neurological examinati on disclosed de-
Fig. I. Diagrammatic representation showing the relationship between the late ral blades of the retractor and the femoral nerve. Anteroposterior projection.
Volume 87 Number 3
creased sensation over the anterior and medial aspect of the left thigh from the groin to the knee, i.e., over the sensory distribution of the left femoral nerve. There was marked inability to extend the left leg at the knee and no left knee jerk could be obtained. The neurological diagnosis was paralysis of the left femoral nerve with almost complete impairment of the motor function. Sensation was only partially impaired. The consultant suggested that the lesion was caused by pressure on the femoral nerve at the lime of operation and since the lesion was incomplete, eventual restoration of function seemed likely. Physiotherapy was begun and ambulation was possible with the aid of a walker. Immediately prior to discharge she was fitted with a knee brace and crutches which permitted greater freedom of movement. The patient was discharged from the hospital on the thirty-sixth postoperative day, with minimal return of function of the left leg. Neurosurgical consultation was obtained during the latter days of her hospital stay, but a continued program of conservative therapy was advised and no serious consideration was given to any surgical approach to the femoral nerve. Four months following the operation, the patient stated that her leg was much stronger and that she could walk unaided. However, at this time, the left patella was completely mobile on examination. Six months postoperatively, the woman was able to run, swim, and work as a practical nurse. Neurological examination eleven months following surgery disclosed slight wasting of the left quadriceps femoris muscle. The left knee jerk was markedly diminished although the reflex was now present whereas it had been absent previously. From a functional viewpoint, the patient's leg continued to perform very satisfactorily until her death on July 7, 1962, 2 years after the initial operation. Autopsy gave no evidence of tumor in the pelvis, but a 16 em. retroperitoneal mass of metastatic adenocarcinoma posterior to the cirrhotic liver and stomach was noted. Detailed gross and microscopic examination of both femoral nerves failed to show any abnormality. The left midthigh measured 4 em. smaller than the right midthigh. Comment
The femoral nerve is the largest branch of the lumbar plexus. It courses downward,
Femoral nerve injury and Pfannenstiel incision
383
passing through the psoas major muscle, then between the psoas and iliacus muscles, entering the thigh lateral to the femoral canal at the midpoint between the anterior superior iliac spine and the pubic tubercle. Constant pressure from the lateral blades of the self-retaining retractor can be exerted on the psoas major muscle and femoral nerve approximately 4 em. proximal to its point of entry into the thigh. The Pfannenstiel incision allows the lateral blades of the retractor to be placed in more intimate contact with the lateral pelvic walls, and therefore with the femoral nerves, than other incisions might permit. A long Pfannenstiel incision would obviously allow more lateral placement of the retractor blades than would a short incision. Routinely the bladder blade of the self-retaining retractor is inserted superiorly, thus increasing the lateral and downward pressure in the area of the femoral nerve. Our third patient, who was the most severely affected, exemplifies the relationship of the woman with a thin abdominal wall to the injury. The thin abdominal wall permits deeper and more lateral placement of the retractor blades. The main muscle that the femoral nerve supplies is the quadriceps femoris. The sensory portion of the nerve supplies the anterior and medial surface of the thigh and leg. In the more advanced lesions, the patient nearly always complains of numbness of the anterior thigh and inability to extend the leg at the knee. On first attempting to stand or walk, the subject usually falls. Each of our three patients collapsed when attempting to stand. Rather simple examination will demonstrate definite weakness of the quadriceps muscle as well as a markedly decreased or absent knee jerk. When the quadriceps muscle contracts, the patella on the weakened leg can be freely moved in many directions. The patella of the uninvolved leg obviously is stable during a similar examination. Careful examination will also demonstrate the sensory loss. Probably many cases that occur are quite mild, the patient experiencing only a
384
Oclolw1 I, l9b:l
McDaniel, Kirkley, and Gilbert
vague weakness in the leg. This weakness spontaneously improves over a period of weeks without ever being detected by the physician. Although bilateral involvement has not been reported, it is certainly possible and could constitute a very serious problem in that the patient would be unable to walk: standing might even be difficult. The management of all the reported cases has been conservative with the use of physiotherapy, knee braces and primarily, time to allow maximum return of nerve function. Fortunately, in most cases reported, the return of function was relatively rapid ( 1 to 24 weeks). Good functional results are undoubtedly attributable to the relatively simple mass functions performed by the muscles innervated by the femoral nerve and to the lack of importance in the thigh of the discriminatory sensation in the areas suppEed by this nerve. o. •> ..t\lthough spontaneous recovery is the rule, recovery is not always spontaneous or complete. Surgical intervention to explore and repair the nerve should be considered if some degree of recovery cannot be den1onstrated after an interval of
three months following the nerve injury." Prevention
By far the most important aspect of this problem involves prevention. Vosburgh and Finn indict a specific type of circular, selfretaining retractor with two solid curved lateral blades. They state that by eliminating this specific retractor, they have encountered no further difficulty with femoral nerve trauma. Winkelman, Johnson, and Montgomery failed to state the types of retractors that were used. We feel that any retractor, particularly a self-retaining retractor, may exert pressure and cause trauma. One of the most important measures of prevention is more careful placement of the lateral blades of the retractor with insertion of a large folded laparotomy pad under each blade to REFERENCES
1. Winkelman, N. W.: AM.
75: 1063. 1958.
J.
0BsT. & Gv;-,;Ec.
:\m.
J. Ohst.
& f;yw·c
cushion and protect the lateral pelvic wall. If a Balfour retractor is selected, the smallest lateral blades should always be used. Sorm' thought should be given to placement of the bladder blade of the Balfour retractor over the symphysis in an effort to decrease downward and lateral pressure in the femoral nerve area.' Placement of the bladder blade in this position would decrease exposure however. The Pfannenstiel incision should not be extended laterally more than is needed to perform the necessary operation because the wider the incision, the greater the likelihood of the retractor exerting pressure in the area of the femoral nerve. Certainly greater care must be taken in the person with the thin anterior abdominal wall. The importance of the underlying disease, nutrition, vitamin deficiencies, radiation, and infection in the pathogenesis of this disorder is not clear. It seems reasonable that these
factors could contribute to the severity of the lesion and the time necessary for recm:ery to occur. We are still frequently using the Pfannenstiel incision and the self-retaining retractor but by following the methods of prevention mentioned, especially the careful cushioning of the lateral retractor blades with a large laparotomy pad, we have had no additional cases of nerve trauma. Summary
1. Three cases of femoral nerve injury with quadriceps femoris paralysis associated with the Pfannenstiel incision and the use of a self-retaining retractor are presented. Autopsy findings are reported in one case. 2. Pressure on the nerve by the lateral retractor blade appears to be the cause of the injury. :1. Conservative management resulted in a functional recovery for all 3 patients. 4. Prevention is the most important aspect of this problem.
2. Johnson, D. A., and Montgomery, R. D.: M. Ann. District of Columbia 27: 513, 1958.
Volume 87 Number :1
3. Ruston, F. G., and Politi, V. L.: Canad. Anaesth. Soc. J. 5: 428, 1958. 4. Vosburgh, L. F., and Finn, W. F.: AM. J. OasT. & Gnmc. 82: 931, 1961. 5. Clare, F. B.: J. Neurosurg. 13: 195, 1956.
Discussion DR. }EsSE CALDWELL, Gastonia, North Carolina. We have heard reported 3 instances of an injury which is easily produced and is no doubt more frequent than is generally known. The responsibility of calling attention to complications resulting from the use of certain procedures or instruments rightfully belongs to the medical profession. It is hoped that public behavior resulting from social and economic trends will not prevent adequate dissemination of such information in the years to come. In addition to those factors mentioned by the authors as being necessary for the occurrence of a femoral nerve injury, another one, the length of operating time, may be considered. In these reported cases, in which an abdominal hysterectomy was performed, the length of operating time would be of interest. Observation may indicate that nerve injuries due to pressure may be rare in procedures of shorter duration. The authors continue to use the transverse in-
Femoral nerve injury and Pfannenstiel incision
385
6. Wen,tworth, Alan, Bell, H. S., and Clare, F. B.: J. A. M. A. 176: 447, 1961. 7. Vosburgh, L. F.: Personal communication. 3025 W. Broward Blvd. Fort Lauderdale, Florida
cision for abdominal-pelvic surgery, but take adequate precautions to prevent trauma to thr abdominal portion of the femoral nerves. Vosburgh and Finn have discontinued the use of a circular self-retaining retractor they found objectionable. The transverse incision and the adjustable circular retractor do offer superior advantages in approach to the pelvis and if at all possible it seems desirable that their use be continued. A technique in the adjustment of the circular self-retaining retractor and the placement of padding under the lateral blades seem to give adequate protection to the femoral nerve as it lies exposed on the wing of the ilium between the psoas major and iliacus muscles near the inguinal ligament. Perhaps in the future the instrument manufacturer will make retractors with shorter lateral blades for use in patients who are slender and have thinner abdominal walls.