Compression neuropathy subsequent to renal transplantation

COMPRESSION NEUROPATHY SUBSEQUENT TO RENAL TRANSPLANTATION zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIH NOSRATOLA DABIR VAZIRI, M.D. JOHN BARNES, KHOSROW M.D. MIRAHMADI, M.D. RICHARD EHRLICH, M.D. STANLEY M. ROSEN, M.D. From the Departments of Medicine and Surgery, University of California, Irvine and Los Angeles, California zyxwvutsrqponmlkjihgfedcbaZYX ABSTRACT - Compression neuropathy occurred in 7 patients who underwent renal transplantation. The neuropathy occurred on the same side as the surgery and was associated with the use of selfretaining retractors. Other contributing factors were presence and degree of uremia and diabetes. W e suggest that self-retaining retractors be used carefully and length of application reduced to a minimum. Efficient dialysis prior to transplantation may decrease the incidence and severity of neurologic deficit by reducing the extent of uremia. Discovery of zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA 1 case of lateral femoral cutaneous the first 6 patients was purely sensory, localized neuropathy after renal transplantation in the Fall to the distribution of lateral femoral cutaneous of I973 prompted close surveillance of all patients nerve. It presented with postoperative developwho underwent transplantation in our instiment of numbness, hyposthesia, and hypoalgesia tutions. As a result, in a total of 7 patients there involving the entire lateral aspect and lateral half developed neurologm deficits of the lower exof the anterior aspect of the thigh.’ These symptremities on the same side as the surgical protoms gradually diminished and disappeared in cedure. The neuropathy was sensory in 6 patients from two and one-half to eight weeks in the first and mixed in 1. Features common to all cases 5 patients, whose transplant kidneys were funcwere use of self-retaining retractors and uremia. tional during the period of follow-up for their neuropathy. The defect was still present in Case 6 eight months later. This patient’s transplantaMaterial and Methods tion was complicated by accidental rupture of the All patients who underwent renal transplantadonor’s renal artery, which could not be repaired, tion in our institutions between July, 1973, and and the kidney had to be removed. ConseFebruary, 1974, were investigated for developquently, he returned to maintenance hemoment of postoperative neurologic deficits. Initial dialysis. and regular follow-up examinations, electroCase 7 had extensive motor deficit involving myography, and nerve conduction studies were main trunk of femoral nerve and was manifested done. Neurologic deficits on the side of operation by marked weakness of quadriceps femoris and were found in 7 patients. Table I provides a sumdepression of the patellar reflex. There was a mary of pertinent clinical data. slight decrease in sensation along the medial aspect of her thigh and leg. This area is supplied Comment by sensory fibers of the femoral nerve.’ Electromyography showed absence of voluntary motor In 7 patients ipsilateral neurologic deficits deunit action potential in the right quadriceps veloped after renal transplantation. The deficit in UROLOGY I FEBRUARY 1976 / VOLUME VII, NUMBER 2 145 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJI TABLE I. Case No. Age (Sex) 1 2 3 4 5 36 IS 24 21 36 6 35 (M) 7 33 (F) CM) (M) (M) (F) (M) Underlying Renal Disease zyxwvuts zyxwv Clinical data in 7 patients Neuropathy Duration Onset Nerve Involved LFC” LFC LFC LFC LFC Immediate Immediate Immediate Immediate Immediate 4 weeks 4 weeks 2.5 weeks 4 weeks 8 weeks Alport’s syndrome LFC Immediate over 10 months Chronic glomerulonephritis F Immediate 8 months Diabetic Chronic Chronic Chronic Chronic nephropathy pyelonephritis glomerulonephritis glomerulonephritis glomerulonephritis Transplant Kidney Function Good initial Excellent Excellent Excellent Fair after 4-week period of poor function Early transplant nephrectomy; back on dialysis Early rejection *LFC = lateral femoral cutaneous; F = femoral. femoris. Nerve conduction study showed no response in right femoral nerve. Physiotherapy was given on a regular basis with gradual improve- Medial and lateral arcuate ligaments Subcortal nerve Quadratus lumborum lliuhypogasrric nerve Ilio-inguinal nerve Proas ma(or Lateral cunneous nerve of thigh iliacus Femoral new? FIGURE 1. M uscles and nerves on posterior abdominal w all (reproduced ji- om Cunningham’s Textbook ofAnatomy , w ith permission of O xford University Press. )” 146 ment of her muscle weakness, but some residual weakness was present at the time of her death eight months later. The nerve injuries in these cases appeared to be associated with surgery. An oblique surgical incision is made in one of the lower quadrants of the abdomen, usually parallel to the inguinal ligament. The iliac fossa is then exposed down to the fascia covering the iliacus and psoas muscles, and a bed is prepared for the transplant kidney. The relationship of the nerves and muscles in this area is illustrated in Figure 1. The lateral femoral cutaneous nerve enters the superior aspect of the surgical field and is exposed throughout much of its course along the superior and lateral aspects of the field. 3 The femoral nerve is beneath the psoas major muscle in the superior aspect of the field but is exposed in about the inferior two thirds of the mid-field. As to the mechanism of nerve injury, direct surgical damage seems unlikely since the major surgical manipulations involve vascular and ureteral anastomoses medial to these nerves. Ischemia due to shunting of blood to the kidney away from the nerves is not the cause, since femoral and lateral femoral cutaneous nerves are not supplied by the hypogastric artery which is used for anastomosis to the donor’s renal artery. Obturator and sciatic nerves are supplied by the hypogastric artery, but there was no evidence of involvement of these nerves. The nerve injury could not be related to anesthesia, since inhalation anesthesia was used in all these cases. We know direct compression is a major cause of nerve injury. In these cases nerve compression by selfretaining retractors (Fig. 2), used in all, seems to be the most likely explanation of the neuropathy. To our knowledge there has been no previous UROLOGY / FEBRUARY 1976 / VOLUME VII, NUMBER 2 The uremic environment of transplant candidates may contribute to the vulnerability of nerves to injury. Diabetes when present is an additional predisposing factor. Uremia not only predisposes to nerve injury but also delays recovery. This is shown in Case 6 whose lateral femoral cutaneous neuropathy persisted over ten months. This contrasts with 5 other patients with similar deficits whose transplant kidneys functioned and were no longer uremic, Their neuropathy cleared up in from two and one-half to eight weeks. Summary FIGURE 2. zyxwvutsrqp zyxwvut Self- retaining retractors in position. report of such neuropathies with renal transplantations. Femoral neuropathies have been reported to occur with gynecologic surgery and self-retaining retractors have been implicated.4-s Similarly, in our cases it is likely that the most lateral blade of the self-retaining retractors had compressed the lateral femoral cutaneous nerve. The important factor with the use of selfretaining retractors is prolonged constant compression of the nerve as opposed to intermittent compression occurring with the use of hand-held retractors. In their classic studies of neuropathies, due to direct compression of peripheral nerves, Denny-Brown and Brenner’ found that there was a threshold in terms of amount and duration of pressure applied beyond which a demyelinated nerve lesion associated with a conduction block would occur. With more severe lesions, secondary axonal damage would result by process of wallerian degeneration. They found that with compression of mixed nerves the motor deficit would be far out of proportion to the sensory deficit, which is often observed clinically with acute compression injury. Case 7 is an example of this phenomenon. UROLOGY / Compressing neuropathy may occur with renal transplantation and is associated with the use of self-retaining retractors. Contributing factors are presence and degree of uremia and diabetes. Involvement of lateral femoral cutaneous nerve is usually mild and is transient. However, with motor neuropathy, paralysis can be severe and disabling with prolonged recovery. We, therefore, suggest that self-retaining retractors be used carefully and the length of application reduced to a minimum. Furthermore, efficient dialysis prior to transplantation may decrease the incidence and severity of neurologic deficit by reducing the extent of uremia. FEBRUA RY 1976 / VOLUM E VII, NUM BER 2 Department of Medicine University of California, Irvine 101 City Drive Orange, South California 92668 (DR. V A ZIRI) References 1. KOPELL, H. P., and THOM PSON,A. L.: Peripheral Entrapment Neuropathies, Baltimore, The W illiams & W ilkins Co., 1963, p. 73. 2. HAYM AKER,W . E., and W OODHALL, B.: Peripheral Nerve Injuries, 2nd ed., Philadelphia, W . B. Saunders Co., 1953, pp. 281-285. Cunningham’s Textbook of 3. ROM ANES, G. J., Ed.: Anatomy, 11th ed., London, Oxford University Press, 1972, p. 758. 4. SINCLAIR, R. H., and PRATT, J. H.: Femoral neuropathy after pelvic operation, Am. J. Obstet. Gynecol. 112: 494 (1972). 5. ROSENBLUM ,J., SCHW ARZ, G. A., and BAENDLER, E.: Femoral neuropathy: a neurologic complication of hysterectomy, J.A.M .A. 195: 499 (1966). Femoral nerve 6. VOSBURGH,L. F., and FINN, W . F.: impairment subsequent to hysterectomy, Am. J. Obstet. Gynecol. 82: 931 (1961). 7. 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