Pathophysiology of tethered cord syndrome and similar complex disorders.

Tethered cord syndrome (TCS) is a stretch-induced functional disorder of the spinal cord due to the fact that its caudal portion is anchored by an inelastic structure. The functional lesion of TCS is generally situated in the lumbosacral cord, and many authors have shown that the syndrome is reversible via surgery to untether the cord. To clarify the expressions relevant to TCS, such as "cord tethering" and "tethered cord," the authors have formulated three categories. These categories include cases that show the anatomical appearance of spinal cord stretching. Among them, Category 1 is isolated to represent the "true TCS." The authors focus their discussion of the pathophysiology of TCS on Category 1 to explain the impaired oxidative metabolism and electrophysiological derangements within the tethered spinal cord, which is the primary intrinsic cause of the dysfunction. Furthermore, they extend the discussion to the extrinsic (outside the spinal cord) factors and other complex conditions that mimic TCS.

Urogenital prolapse and occult stress urinary incontinence.

BACKGROUND: A 76-year-old female presented to an outside clinic with symptoms of pelvic prolapse; she denied stress urinary incontinence (SUI). The patient had a history of two prior anti-incontinence surgeries. Pelvic examination revealed a grade IV cystocele. No SUI was identified, with or without reduction of the prolapse. Anterior colporrhaphy with cadaveric fascia was performed. Her prolapse symptoms resolved, but she had new-onset severe SUI. INVESTIGATIONS: Pelvic examination, cystoscopy, urodynamics. DIAGNOSIS OCCULT: SUI unmasked after anterior colporrhaphy. MANAGEMENT: The patient was referred to our institution where videourodynamics were performed, revealing a well-supported bladder and SUI with Valsalva leak-point pressure of 26 cm H20. A transvaginal polypropylene sling was placed. She had complete resolution of SUI and denied exacerbation of mild urgency.

Vesicovaginal fistula and mesh erosion after Perigee (transobturator polypropylene mesh anterior repair).

The transobturator polypropylene mesh system is a new approach in the surgical treatment of anterior vaginal wall prolapse. We report the case of a 57-year-old woman who developed a vesicovaginal fistula with erosion of the mesh into the bladder and vagina after Perigee transobturator, polypropylene mesh anterior repair. This is a serious complication associated with this technique. Treatment required an open vesicovaginal fistula repair with excision of the exposed and nearby surrounding mesh.

High rate of vaginal erosions associated with the mentor ObTape.

PURPOSE: The transobturator tape method is a newer surgical technique for the treatment of stress urinary incontinence. Limited data exist related to complications with this approach or the types of mesh products used. We report our experience with vaginal erosions associated with the Mentor ObTape and American Medical Systems Monarc transobturator slings. MATERIALS AND METHODS: Beginning in December 2003 selected female patients with anatomic urinary incontinence were prospectively followed after placement of the Mentor ObTape. Beginning in January 2004 we also began using the American Medical Systems Monarc in similar patients. Patients were admitted overnight after surgery, discharged on oral antibiotics, and seen in the clinic at 6 weeks postoperatively. RESULTS: A total of 67 patients have undergone placement of the Mentor ObTape and 9 of those patients (13.4%) have had vaginal extrusions of the sling. Eight patients reported a history of persistent vaginal discharge. One patient presented initially to an outside facility with a left thigh abscess tracking to the left inguinal incision site. Each patient was taken back to the operating room for mesh removal. A total of 56 patients have undergone placement of the AMS Monarc and none have had any vaginal erosions. CONCLUSIONS: Our high rate of vaginal extrusion using the ObTape has led us to discontinue the use of this product in our institution. Continued followup of all of these patients will be of critical importance.

Pathophysiology of tethered cord syndrome and other complex factors.

There are different interpretations of tethered cord syndrome (TCS) partly due to difficulty in understanding the concept of this syndrome as a functional disorder not merely based on gross anatomy of congenital anomalies. The essential mechanical factor of cord tethering is that any of the inelastic structures fastening the caudal end of the spinal cord produces traction effects on the lumbosacral cord. The production of such traction is the key to understanding this disorder. In a significant number of patients who present with the typical clinical signs and symptoms of TCS, the diameter of the filum terminale is found within normal limits and the caudal end of the spinal cord is located in the normal position. Therefore, the definition of TCS requires the demonstration that there is a posterior displacement of the conus and filum by MRI, lack of viscoelasticity by the stretch test of the filum during surgery, and fibrous displacement of glial tissue within the filum by histological studies. This is because there is inconsistency from such studies as ultrasonography, MRI and CT myelography, which attempt to establish the presence of a tight filum terminale. A goal of this article is to provide basic understanding of TCS so that clinicians can use the concept of stretch-induced spinal cord dysfunction for proper diagnosis and treatment of this disorder.