1/28. Distal disinsertion of the patellar ligament combined with avulsion fractures at the medial and lateral margins of the patella. A case report and an experimental study.A 12-year-old boy presented with a proximally retracted patella 5 months after an injury to the left knee. The clinical and radiographic features and the findings at operation led to the conclusion that the original lesion had been a distal disinsertion of the patellar ligament combined with avulsion fractures at the medial and lateral margins of the patella, produced by the medial and lateral longitudinal patellar retinacula. Loading experiments on amputation and cadaver specimens showed that these retinacula, apart from being tendons for the vastus medialis and the vastus lateralis, respectively, constitute a direct fibrous connection of considerable strength between the patella and the tibia and thus are capable of producing avulsion fractures.- - - - - - - - - - ranking = 1keywords = ligament (Clic here for more details about this article) |
2/28. Diffuse glomerular basement membrane lamellation in renal allografts from pediatric donors to adult recipients.The transplantation of kidneys from pediatric cadaveric donors into adult recipients is performed in many centers. However, some studies indicate that the outcome of such renal transplants may be inferior compared with that of adult donors, particularly if the donor is an infant. Morphologic studies of failed pediatric donor kidneys in adult recipients describe various degrees of segmental or global glomerular sclerosis. The authors have performed ultrastructural examinations on such transplants and have identified six cases with diffuse irregular lamellation of the glomerular basement membrane (GBM), a change that may develop as early as 10 weeks after transplantation. The age of all donors was < or =6 years; three were infants. The incidence of the lesion was 9% at our institution in renal transplant patients who received a graft from donors <10 years old. Diffuse GBM lamellation has not been found in renal transplants from adult donors. light microscopy showed various degrees of diffuse mesangial expansion, usually with segmental glomerular sclerosis. The patients had severe proteinuria. While recurrent focal segmental glomerular sclerosis (FSGS) has to be excluded, such diffuse GBM lamellation is generally not seen in recurrent FSGS cases. The pathogenesis of the lesion is most likely related to hyperperfusion injury of small pediatric donor kidneys grafted into adult recipients.- - - - - - - - - - ranking = 0.0068160283910963keywords = membrane (Clic here for more details about this article) |
3/28. A keyhole approach for endoscopically assisted pedicle screw fixation in lumbar spine instability.OBJECTIVE: The standard approach for dorsal transpedicular fixation in lumbar spine instability requires extensive exposure of the vertebral column. This increases the risk of potential complications and possibly destabilizes healthy neighboring segments because of the dissection and denervation of paravertebral muscles. The majority of spinal disorders are currently treated successfully via limited and tailored approaches. Accordingly, a keyhole approach for dorsal fusion of the lumbar spine was developed on the basis of an anatomic study. methods: The new endoscopic technique entails the transmuscular insertion of a pedicle screw-rod fixation device via a rigid operating sheath. As a prerequisite, the endoscopic microanatomy of the target area, as visible through the operating sheath, was first evaluated on lumbar bone specimens. To localize the exact screw entry point into the pedicle, we identified the bony and ligamentous landmarks on partly macerated specimens. To determine the course of the pedicle screws, we deduced the corresponding angles of convergence from transparent polyester casting models of average vertebrae from T12 to S1. These angles were transferred into the operative situation and measured on-line with an inclinometer. The approach was finally tested on 12 cadavers for clinical feasibility and accuracy of screw placement and then successfully implemented in patients. RESULTS: After extracutaneous localization of the pedicles at lateral fluoroscopy, paramedian skin incisions were made above the pedicles of the motion segment to be stabilized. The operative windows were exposed by use of a rigid operating sheath (length, 50 mm; diameter, 15 mm), which was inserted transmuscularly in the pedicle axis. The screw entry point into the pedicles was localized by endoscopic dissection of the mamilloaccessory ligament, bridging the mamilloaccessory notch. The pilot holes were created via insertion of a blunt-tipped pedicle probe. The adequate angles of convergence were constantly controlled during hollowing of the pedicles by an inclinometer mounted to the pedicle probe handle. The pedicle screws were then inserted through the operating sheaths. After removal of the operating sheaths, the connecting rods were inserted transmuscularly and anchored in the pedicle screw heads. Posterior bone grafting was performed after completion of the dorsal instrumentation. The dorsal fusion site was exposed by reinserting the operating sheath and tilting it medially. CONCLUSION: This new approach significantly reduces surgical traumatization and destabilization of adjacent motion segments. An endoscopic operating sheath, adopted from thoracoscopic surgery, creates space for visualization and surgical manipulations. The newly defined anatomic landmarks provide guidance to the screw entry point into the pedicle in the center of the exposure. observation of the exact corresponding angles of convergence during screw insertion by an inclinometer facilitates correct screw placement. In accordance with the initial anatomic studies, this approach was successfully performed on 12 cadavers and then used in six patients. Two illustrative cases are presented.- - - - - - - - - - ranking = 0.4keywords = ligament (Clic here for more details about this article) |
4/28. Serial complement studies in a patient with Goodpasture's syndrome treated with bilateral nephrectomy and renal transplantation.A young male patient with Goodpasture's syndrome was treated with bilateral nephrectomy and when antiglomerular basement membrane antibodies could no longer be detected he received a cadaveric renal homograft. Fifteen months later he is in good health and without signs of pulmonary disease. Renal function is satisfactory, and there are no findings indicating recurrence of the nephritis. Serial complement studies during the entire course revealed varying degrees of activity in the sequence in the different phases: a high degree of in vivo activation of complement was found in the period before the nephrectomy, there was a moderate degree of activation in the period between the nephrectomy and transplantation and, finally, there were no signs of activity in the system after transplantation. This investigation strongly suggests that the complement system is of definite pathogenetic significance in this human equivalent to experimental nephrotoxic nephritis.- - - - - - - - - - ranking = 0.0013632056782193keywords = membrane (Clic here for more details about this article) |
5/28. Subclavius posticus muscle: supernumerary muscle as a potential cause for thoracic outlet syndrome.During routine dissection a subclavius posticus muscle was found on the left side of a male cadaver. This muscle arose from the upper margin of the scapula and transverse scapular ligament, inserted in the superior side of the first rib cartilage, and was innervated by a small branch from the suprascapular nerve. The anatomical relationships of the supernumerary muscle with the brachial plexus and the subclavian artery is suggestive of a possible cause of the thoracic outlet syndrome and therefore of clinical significance.- - - - - - - - - - ranking = 0.2keywords = ligament (Clic here for more details about this article) |
6/28. Diastasis with low distal fibula fractures: an anatomic rationale.Tibiofibular diastasis occurs infrequently in displaced ankle fractures that include a low fibula fracture. This is because the interosseous ligament, the major ligament resisting diastasis, lies above the level of the fracture. The anatomic study of the syndesmotic complex of the ankle reported here showed that the interosseous ligament has a variable attachment on the fibula, differing between specimens in its distance above the synovial reflection or joint line. Although most specimens had attachments approximately 1 cm or greater above the joint line, one of 18 specimens attached just above the synovial reflection. In such a case, a low fibula fracture would disrupt the interosseous ligament, which explains the anatomic basis for the infrequent diastasis in these ankle fractures.- - - - - - - - - - ranking = 0.8keywords = ligament (Clic here for more details about this article) |
7/28. Extraforaminal entrapment of the fifth lumbar spinal nerve by osteophytes of the lumbosacral spine: anatomic study and a report of four cases.STUDY DESIGN: An anatomic study of the associations between the fifth lumbar spinal nerve (L5 spinal nerve) and a lumbosacral tunnel, consisting of the fifth lumbar vertebral body (L5 vertebral body), the lumbosacral ligament, and sacral ala, and clinical case reports of four patients with lumbar radiculopathy secondary to entrapment of the L5 spinal nerve in the lumbosacral tunnel. OBJECTIVES: To delineate the anatomic, clinical, and radiologic features and surgical outcome of patients with entrapment of the L5 spinal nerve in the lumbosacral tunnel. SUMMARY OF BACKGROUND DATA: Although several cadaveric studies on a lumbosacral tunnel as a possible cause of L5 radiculopathy have been reported, few studies had focused on osteophytes of the L5-S1 vertebral bodies as the major component of this compressive lesion, and clinical reports on patients with this disease have been rare. methods: Lumbosacral spines from 29 geriatric cadavers were examined with special attention to the associations between osteophytes of the L5-S1 vertebral bodies and the L5 spinal nerve. Four patients with a diagnosis of the entrapment of the L5 spinal nerve by osteophytes at the lumbosacral tunnel were treated surgically, and their clinical manifestations and surgical results were reviewed retrospectively. RESULTS: The anatomic study demonstrated osteophytes of the L5-S1 vertebral bodies in seven of the 29 cadavers. Entrapment of the L5 spinal nerve in the lumbosacral tunnel was observed in six of the seven cadavers with L5-S1 osteophytes but in only one of the 22 cadavers without such osteophytes (P < 0.05, chi2 test). All four patients had neurologic deficits in the L5 nerve root distribution. MRI and myelography showed no abnormal findings in the spinal canal, but CAT scans demonstrated prominent osteophytes on the lateral margins of L5-S1 vertebral bodies in all four. Selective L5 nerve block completely relieved all patients of pain but only temporarily. Three patients were treated via a posterior approach by resecting the sacral ala along the L5 spinal nerve, and the other patient was treated by laparoscopic anterior resection of the osteophytes. pain relief was obtained in the four patients immediately after surgery, but one patient experienced recurrence of pain 1 year after the first surgery and was successfully treated by additional posterior decompression and fusion. CONCLUSIONS: Extraforaminal entrapment of L5 spinal nerve in the lumbosacral tunnel can cause L5 radiculopathy, and osteophytes of L5-S1 vertebral bodies are a major cause of the entrapment.- - - - - - - - - - ranking = 0.2keywords = ligament (Clic here for more details about this article) |
8/28. Limited macular translocation with scleral retraction suture.BACKGROUND/AIMS: Macular translocation with scleral imbrication is a new technique for treating subfoveal choroidal neovascular membranes (CNV). This procedure shortens the sclera but may result in a minimal decrease in the internal circumference of the globe and limits the amount of foveal displacement. The authors propose a new scleral retraction suture aimed at decreasing the internal circumference of the globe in an effort to increase foveal displacement. methods: Using a cadaver model, they compared the amount of scleral shortening using a standard scleral imbrication technique and a modified three suture scleral retraction technique. Sections of the globes were digitised and specialised software was used to estimate the amount of scleral shortening. Three patients with subfoveal choroidal neovascularisation underwent limited macular translocation using pars plana vitrectomy and macular detachment with the modified scleral suture technique. The main outcome measures were visual acuity, foveal displacement, and complications. RESULTS: In the cadaver model, the scleral retraction suture resulted in a flatter internal scleral fold compared to the standard suture technique and created approximately 890 microm of effective scleral shortening. In the patients who underwent macular translocation and laser photocoagulation of the CNV, visual acuity improved in two patients and worsened in one patient. The range of foveal displacement was 1400-2400 microm. CONCLUSION: The foveal displacements achieved in this limited study compared to median displacement previously published using standard suture techniques demonstrates that the scleral retraction suture technique may be a useful adjunct to limited macular translocation. The advantage of this type of suture in conjunction with translocation may depend on the effective scleral shortening offered by this retraction suture.- - - - - - - - - - ranking = 0.0013632056782193keywords = membrane (Clic here for more details about this article) |
9/28. wrist arthroscopy through a volar radial portal.PURPOSE: To quantitatively describe the neurovascular relationships of a volar radial wrist arthroscopy portal and to evaluate whether volar wrist arthroscopy identified additional pathology of the dorsal capsular structures and the palmar region of the scapholunate interosseous ligament that was not seen through the dorsal portals. TYPE OF STUDY: This study was an anatomic study and retrospective chart review. methods: cadaver dissections established the neurovascular anatomy of the volar radial portal. Measurements were taken from the portal to the radial artery and its superficial palmar branch; the superficial radial nerve, the median nerve, and its palmar cutaneous branch; and the pronator quadratus. A dorsal capsulotomy was performed to assess the ligamentous interval. A chart review of 30 patients in whom a volar radial portal was used was performed. Intraoperative pathology identified through volar wrist arthroscopy that was not visible through a dorsal portal was recorded. Postoperative neurovascular complications were noted. RESULTS: There was a greater than 3 mm safe zone surrounding the portal that was free of any neurovascular structures. There were no complications from the use of the portal. Additional pathology that was not visible from a dorsal portal was identified in 10 cases. This included 1 case of hypertrophic synovitis of the dorsal capsule, 1 patient with an avulsion of the radioscapholunate ligament, 1 patient with a tear restricted to the palmar region of the scapholunate interosseous ligament, and 7 patients with tears of the dorsal radiocarpal ligament. CONCLUSIONS: This study provides a safe, standardized approach to the volar radial aspects of the radiocarpal and midcarpal joints. Volar wrist arthroscopy identified additional pathology of the palmar scapholunate interosseous ligament and dorsal capsular structures in 30% of the patients. The volar radial portal should be considered for inclusion in the arthroscopic examination of any patient with radial-sided wrist pain.- - - - - - - - - - ranking = 1.2keywords = ligament (Clic here for more details about this article) |
10/28. The ultrasonographic appearance of the femoral nerve and cases of iatrogenic impairment.OBJECTIVE: To assess the feasibility of ultrasonography of femoral nerves in a cadaveric specimen, healthy volunteers, and patients. methods: In 1 unembalmed cadaveric specimen (female, 90 years) and 20 healthy volunteers (9 male and 11 female, 18-50 years; n = 40 scans), the topographic features, cross-sectional shapes (oval or triangular), and cross-sectional areas of the femoral nerves were evaluated by ultrasonography (5- to 12-MHz broadband linear array). In a subsequent study, 7 consecutive patients with postoperative findings assigned to the femoral nerve were evaluated and assessed by a neurologist. RESULTS: The mean /- SD anteroposterior and mediolateral diameters of the femoral nerves in the volunteers were 3.1 /- 0.8 and 9.8 /- 2.1 mm, respectively, at an average cross-sectional area of 21.7 /- 5.2 mm2. The cross-sectional shape was oval in 67.5% superior to the inguinal ligament and in 95% inferior to the ligament. The infrainguinal femoral nerve showed variable distances to the femoral artery. In the subsequent patient study, 5 patients had swelling of the femoral nerve in the affected side. In 1 patient, the nerve had a blurred echo structure due to a hematoma. In 1 patient, major damage of the femoral nerve was ruled out clearly. CONCLUSIONS: ultrasonography allows the depiction and assessment of the femoral nerve from about 10 cm superior to 5 cm inferior to the inguinal ligament. In this region, ultrasonography is helpful in detection of impairments and, therefore, in decisions about planning and even acceleration of further treatment.- - - - - - - - - - ranking = 0.6keywords = ligament (Clic here for more details about this article) |
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