Yasuhiro Chiba

Microsurgical Decompression for Peroneal Nerve Entrapment Neuropathy.

Peroneal nerve entrapment neuropathy (PNEN) is one cause of numbness and pain in the lateral lower thigh and instep, and of motor weakness of the extensors of the toes and ankle. We report a less invasive surgical procedure performed under local anesthesia to treat PNEN and our preliminary outcomes. We treated 22 patients (33 legs), 7 men and 15 women, whose average age was 66 years. The mean postoperative follow-up period was 40 months. All patients complained of pain or paresthesia of the lateral aspect of affected lower thigh and instep; all manifested a Tinel-like sign at the entrapment point. As all had undergone unsuccessful conservative treatment, we performed microsurgical decompression under local anesthesia. Of 19 patients who had undergone lumbar spinal surgery (LSS), 9 suffered residual symptoms attributable to PNEN. While complete symptom abatement was obtained in the other 10 they later developed PNEN-induced new symptoms. Motor weakness of the extensors of the toes and ankle [manual muscle testing (MMT) 4/5] was observed preoperatively in 8 patients; it was relieved by microsurgical decompression. Based on self-assessments, all 22 patients were satisfied with the results of surgery. PNEN should be considered as a possible differential diagnosis in patients with L5 neuropathy due to lumbar degenerative disease, and as a causative factor of residual symptoms after LSS. PNEN can be successfully addressed by less-invasive surgery performed under local anesthesia.

Long-term Outcome of Surgical Treatment for Superior Cluneal Nerve Entrapment Neuropathy

Study Design. Prospective observational cohort study. Objective. The objective of this study was to present the long-term surgical outcomes of operative treatment for superior cluneal nerve (SCN) entrapment neuropathy (SCNEN) and to analyze the causes of poor results and further treatment required. Summary of Background Data. There are a few reports of the outcomes of surgical treatment for SCNEN, and most studies describe results for operations conducted under general anesthesia with short follow-up periods. Methods. Surgery was performed for SCNEN in 52 consecutive patients on 79 sides, excluding patients who had undergone previous surgery on the lumbar spine. Entrapment was unilateral in 25 patients and bilateral in 27. The mean postoperative follow-up period was 41.3 months (range, 29–58 months). All patients had received conservative treatment without improvements, and operations were performed under local anesthesia. Results. Twenty-three cases (44%) involved only low-back pain (LBP), and 31 cases (60%) involved LBP associated with leg numbness or pain. The mean number of SCN branches decompressed in the operative field at the first operation was 1.4 (range, 1–4 branches). There were no local or systemic complications during or after the operation. All patients reported symptom improvement, but LBP caused by SCNEN recurrence was reported for 10 sides (13%) in seven patients who subsequently underwent repeat surgery. In the second surgery, the number of additionally treated SCN branches was 2.0 (range, 1–5). Additional surgeries were performed in two cases for lumbar disorders. All patients showed significant improvement at the last follow-up visit (Pu200a<u200a0.05), including those who developed recurrence. Conclusion. Long-term outcomes of surgical treatment for SCNEN were satisfactory. For prevention of recurrence, as many SCN branches as possible should be decompressed in the operation field during the first operation. Level of Evidence: 4

Neurovascular bundle decompression without excessive dissection for tarsal tunnel syndrome.

Tarsal tunnel syndrome (TTS) is an entrapment neuropathy of the posterior tibial nerve and its branches in the tarsal tunnel. We present our less invasive surgical treatment of TTS in 69 patients (116 feet) and their clinical outcomes. The mean follow-up period was 64.6 months. With the patient under local anesthesia we use a microscope to perform sharp dissection of the flexor retinaculum and remove the connective tissues surrounding the posterior tibial nerve and vessels. To prevent postoperative adhesion and delayed neuropathy, decompression is performed to achieve symptom improvement without excessive dissection. Decompression is considered complete when the patient reports intraoperative symptom abatement and arterial pulsation is sufficient. The sensation of numbness and/or pain and of foreign substance adhesion was reduced in 92% and 95% of our patients, respectively. In self-assessments, 47 patients (68%) reported the treatment outcome as satisfactory, 15 (22%) as acceptable, and 7 (10%) were dissatisfied. Of 116 feet, 4 (3%) required re-operation, initial decompression was insufficient in 2 feet and further decompression was performed; in the other 2 feet improvement was achieved by decompression of the distal tarsal tunnel. Our surgical method involves neurovascular bundle decompression to obtain sufficient arterial pulsation. As we use local anesthesia, we can confirm symptom improvement intraoperatively, thereby avoiding unnecessary excessive dissection. Our method is simple, safe, and without detailed nerve dissection and it prevents postoperative adhesion.

Thermosensitive Determination of Patency in Lumboperitoneal Shunts: Technical note

Surface cooling and thermistor recording over shunt tubing was used in 23 studies of cerebrospinal fluid shunt patency in 19 patients with lumboperitoneal shunts and normal-pressure hydrocephalus. Shunt patency was shown by downward reflection of the recording trace similar to that obtained for ventriculoperitoneal shunts. Obstruction was demonstrated by a flat-line recording or an upward deflection.

A Diagnostic Scoring System for Sacroiliac Joint Pain Originating from the Posterior Ligament

Objective. Sacroiliac joint (SIJ) pain originating from the posterior ligament manifests in not only the buttocks but also the groin and lower extremities and thus may be difficult to discern from pain secondary to other lumbar disorders. We aimed to develop a simple clinical diagnostic tool to help physicians distinguish between patients with SIJ pain originating from the posterior ligament and those with lumbar disc herniation (LDH) or lumbar spinal canal stenosis (LSS). Design. Prospective case-control study. Patients and Methods. We evaluated 62 patients with SIJ pain originating from the posterior ligament and 59 patients with LDH and LSS. Pain areas, pain increasing positions, provocation test, and tenderness points were investigated. A scoring system based on multivariate logistic regression equations using the investigated items was developed. Results. Two pain areas (the posterosuperior iliac spine (PSIS) detected by the one-finger test and groin), pain while sitting on a chair, provocation test, and two tenderness points (PSIS and the sacrotuberous ligament) had high odds ratios (range, 25.87–1.40) and were used as factors in the scoring system. An integer score derived from the regression coefficient and clinical experience was assigned to each identified risk factor. The sum of the risk score for each patient ranged from 0–9. This scoring system had a sensitivity of 90.3% and a specificity of 86.4% for a positivity cutoff point of 4. Conclusion. The scoring system can help distinguish between patients with SIJ pain originating from the posterior ligament and those with LDH and LSS.

Ultrastructural studies on the exocrine pancreas of the dog after hemigastrectomy combined with vagotomy

Ult ras t ruc tu ra l changes in the exocrine pancreas of the dog af ter hemigas t rec tomy combined with vagotomy were studied in a purpose to ascer ta in effects of such operat ive procedures on funct ion of other abdominal viscera. Fourty-seven dogs were divided into four groups; control (without operat ive procedures, hemigastrectomy), hemigas t rec tomy combined wi th total t runcal vagotomy and hemigas t rec tomy with selective gastr ic vagotomy. One week af ter any kinds of operation, the pancreat ic acinar cells appeared to be declined in function, that is, they contain small Golgi appara tus and well-developed g ranu la r endoplasmic re t iculum with lamel lar flattened contour. Such phenomena suggest ing hypofunction of the exocrine pancreas changed into those of the considerable res tora t ion in funct ion which include well-developed Golgi appara tus and vesicular profiles of the g ranu la r re t iculum two weeks af te r hemigas t rec tomy and combinat ion of hemigas t rec tomy and selective gast r ic vagotomy, while such changes remained min imum af ter hemigas t rec tomy combined with total t runcal vagotomy. However, in all groups of exper iments the ac inar cells appeared to be active in secret ion one month af ter operat ions, and moreover, in cases of total t runcal vagotomy i r regula r profiles of distended granu la r endoplasmic ret iculum were occasionally observed. Such a finding was more conspicuous in cases three months af te r total vagotomy. It is considered that this depends upon an abnormal accelerat ion of secretory funct ion under a condit ion without neural regulation. In conclusion, it might be said tha t a combinat ion of selective vagotomy is useful to prevent abnormal phenomena without neural regulat ion which have occurred af te r total vagotomy.