Sciatic Neuropathy: Case Report and Discussion of the Literature on Postoperative Sciatic Neuropathy and Sciatic Nerve Tumors

Sciatic nerve injury and dysfunction is not an uncommon cause of lower extremity symptoms in a musculoskeletal practice. We present the case of a man who presented with lower extremity weakness, pain, and cramps, and was initially diagnosed at an outside institution with bilateral S1 radiculopathies and recommended for spine surgery. He came to us for a second opinion. Electrodiagnostic testing revealed an isolated sciatic neuropathy and the patient was referred for imaging, which showed a sciatic nerve sheath tumor. Review of the literature on sciatic neuropathies shows that there can be many possible etiologies of sciatic nerve dysfunction, but that hip arthroplasty continues to be the leading risk factor. Sciatic nerve tumors are not commonly described in the literature and their definitive management remains unclear.     

Technetium-99-labelled methylene diphosphonate uptake scans in patients with dialysis arthropathy

Patients on long-term haemodialysis suffer from dialysis arthropathy due to the deposition of dialysis amyloid. We investigated the use of 99Tc-labelled methylene diphosphonate bone scans in 17 patients as a possible in vivo diagnostic technique. In most clinically affected joints, with the exception of shoulders and hands, there was increased radioisotope uptake consistent with uptake by periarticular bone. In addition, we describe intense soft-tissue uptake around some clinically affected large joints. In contrast, control groups of patients on haemodialysis without arthropathy and patients without renal failure did not have increased uptake. A semi-quantitative scale of uptake was devised, and the following correlations were significant: pain perception and isotope uptake score in the ankles and feet, and the number of radiological lesions and isotope uptake scores in the wrists and knees. The following sites where the radioisotope might bind in the affected joints are proposed: amyloid deposits, areas of soft-tissue calcification, or areas of increased bone turnover. It is concluded that whereas the scanning technique cannot make a definite diagnosis of amyloid and, therefore, cannot be expected to supersede histological diagnosis, it is a useful adjuvant investigation, of particular importance in those patients unable or unwilling to undergo biopsy.     

Circulating testosterone in pure motor stroke

Serum LH, FSH and testosterone were quantitated in 9 patients with pure motor stroke within 24-48 h of its reported onset. High circulating LH with normal or low testosterone was noted in 8 of them. In response to an intravenous bolus of GnRH, the LH responses were exaggerated in all, but the FSH responses in 7 of them were comparable to those in eugonadal age matched controls. The rise in testosterone following 2000U hCG daily for 3 consecutive days was insignificant in the patients group compared to the controls. The data suggest normally operative pituitary testicular feed-back but decreased Leydig cell response in pure motor stroke.     

A parallel group randomised comparative study of felodipine and nifedipine in hypertension.

We compared the antihypertensive effects and tolerability of a new calcium channel antagonist felodipine with nifedipine in an open randomised parallel group study in 49 patients with moderate hypertension (diastolic blood pressure 105-120 mm Hg). After two weeks run in period felodipine 5 mg and 10 mg once daily was compared with nifedipine 10 mg tid for an active treatment period of 4 weeks. Twenty three patients (mean age 42 +/- 10 years) received felodipine 5 mg once daily for first 2 weeks and 10 mg once daily for subsequent 2 weeks. Twenty six patients (mean age 45 +/- 9 years) received nifedipine 10 mg tid for 4 weeks. The mean reduction in supine diastolic blood pressure in two groups was 17 +/- 6 mm Hg (nifedipine) and 19 +/- 8 mm Hg (felodipine) (p = NS). The goal diastolic blood pressure of less than or equal to 90 mm Hg was achieved in 31 percent (nifedipine group) and 43.5 percent (felodipine group) of patients (p = NS). Side effects were common with both drugs; however, the tolerability was better with felodipine than with nifedipine. In conclusion felodipine was as effective as nifedipine and had the advantage of once a day dosage.     

The effect of naloxone on the preoperative gastric volume and pH

The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs.     

Long term performance of silicone insulated and polyurethane insulated cardiac pacing leads.

The long term performance of various pacing leads in use for at least one year is reported from one centre. Between January 1975 and December 1990, 1056 cardiac pacing leads were implanted in 881 patients (mean age 57 +/- 13 years). Eight hundred and three leads were silicone insulated (SI) and 253 leads were polyurethane insulated (PUI). Leads from different manufacturers were used (Medtronic, CPI, Telectronics). The average duration of follow up was 56.6 +/- 77 months (range 12-221 months) for SI and 47.1 +/- 24 months (range 12-99 months) for PUI leads. Overall lead failure occurred more often in the PUI group (n = 46, 18.2%) compared to SI group (n = 93, 11.3%, p < 0.025). Majority of lead failures occurred in the first 36 months after implantation. In particular, Medtronic models 6971, 6972 (urethane) and 6901 (silicone) showed higher rate of complications (25.5%, 26.3% and 44.5% respectively).