Topographic relations between the neural and ligamentous structures of the lumbosacral junction: in-vitro investigation.

Transient or persistent alterations in the L5 lumbar nerve root have been described as a complication after the reduction of spondylolistheses. In a retrospective analysis of our own patients, we observed a higher incidence of transient motor and sensomotor deficits after single-sitting anatomic correction of May-erding grade IV anterolistheses and spondyloptoses. These findings are consistent with those of other authors. The deficits pertained to muscles in the innervation range of the L5 nerve root, without there being any evidence of intradural root damage or nerve compression. In vitro studies have shown distraction and translation of the nerve root to be pathogenetically relevant mechanisms, leading to damage during intraoperative reduction. Additional alteration of neuronal structures may be caused by ventral parts of the iliolumbar ligament complex during the reduction maneuver. In order to reveal extradural constrictions of the L5 nerve root that might predispose towards intra- or perioperative damage, we examined anatomic specimens to determine the course and neighboring relationships of the lumbosacral plexus, especially in relation to pelvivertebragenic ligamentous connections. In addition to the morphologic considerations, we conducted translation tests, which were designed to simulate changes in shape and size of the epineural layer, as well as in vitro measurements of the resulting pressure on the nerve. In addition to a range of variations in the attachment of the iliolumbar ligament complex, which was always located dorsally to the nerve roots, we found a ligamentous connection formed by connective tissue between the sacrum and the fifth lumbar vertebral body on the caudal margin of the ligament apparatus in 14 out of 30 specimens. Its course was constantly ventral to the L5 nerve root, which was also adherent to the periosteum of the sacrum distal to this constriction in one-fifth of the specimens. The average pressure exerted on the nerve root during the distraction and translation process was over 30 mmHg in the area of this lumbosacral ligamentous connection, at a distance of greater than 20 mm. When the translation distance was further increased, perineural fatty tissue was discharged, due to increasing perineural pressure.

[Repositioning injuries of nerve root L5 after surgical treatment of high degree spondylolistheses and spondyloptosis--in vitro studies]. / Repositionsverletzungen der Nervenwurzel L5 nach operativer Behandlung höhergradiger Spondylolisthesen und Spondyloptosen--In vitro Untersuchungen.

Temporary or persistent paralysis of the fifth lumbar nerve root have been frequently reported as complications following reposition of high degree spondylolisthesis. According to an outcome analysis of sixty-four patients, we found an increased incidence of motor damages after reduction of Meyerding degree four anterolisthesis or spondyloptosis. There were no signs of intradural root compression or nerve injury tracable. In order to detect extraforaminal strictures, the anatomic course of the lumbosacral plexus and its relation to neighbouring structures, especially pelvivertebral connective tissue junctions were recorded in cadavric measurements. Beside an number of variations in origin and course of the iliolumbar ligament complex, we observed a junction between os sacrum and the anterior part of the fifth lumbar vertebrae in 14/30 specimen, constantly running anterior to the fifth lumbar nerve root. In addition the nerve was fixed to the sacral periostium a few centimeters distal this crossing in about 20% of all cases. Pathophysiological effects were measured in reposition trials, using a continuous pressure monitoring system. A reposition of more than 20 mm resulted in a perineural pressure > 30 mmHg. This caused a nerve fiber deformation at the edge of the compressed nerve segment. Increased pressure leads to a nodular displacement of perineural fat as well as intraneural fascicles.

[Functional neuroanatomy of the radial nerve in the region of the long wrist and finger joint extensors and the supinator groove]. / Funktionelle Neuroanatomie des N. radialis im Bereich der langen Hand- und Fingergelenksstrecker und des Supinatorschlitzes.

Basing on electrophysiological data measured by us we studied the course of the radial nerve or its motoric branches with regard to anatomically conditioned bony contractions and their possible significance for pain experienced at the radial epicondyle of humerus, the pain being known under several synonymous designations. To differentiate between the various pathomechanisms discussed in the literature, we performed longitudinal and transversal dissections on a total of 40 cadaveric arms. We found as constant variations to the topographic anatomy published in the standard literature a regularly extended and (in relation to the other muscles we examined) exposed course of the nerve branch proceeding towards the m. extensor carpi radialis brevis. As the only long wrist extensor muscle this is innervated in most cases from the superficial end branch of the radial nerve. The origin of the muscle projected regularly over the common aponeurosis of the extensor tendon and delimitated in most of the preparations the distal end of the tunnel of the deep radial nerve. Since the deep radial branch and the muscular branches parallel to that branch cross this part of the tendon at an obtuse angle we believe that the repeatedly discussed possibility of a dynamic nerve compression without structural influences is the triggering mechanism for the observed nerve damage.

[Neurophysiologic findings in radio-humeral epicondyle pathology]. / Neurophysiologische Befunde bei radiohumeraler Epikondylopathie.

A number of authors assumed a compression syndrome of the radial nerve or its branches to be responsible for the heterogenous classified picture of radiohumeral epicondylopathy. Various structural and functional stenoses have been discussed as possible causes. We performed electromyographies on the extensor muscles, subdividing from the radial epicondyle and found significant (p < 0.05) changes in 27/51 patients regarding latency, velocity of neural conduction and rate of polyphasic potentials. Especially affected were the extensor carpi radialis brevis and extensor digitorum muscle. These findings were confirmed by torque measurements and histologic observations from both muscular and tendon biopsies. In summary, we believe the model of a neurogenous origin of radio-humeral epicondylopathy to be an appropriate explanation.

[Results of surgical treatment of radio-humeral epicondylopathy]. / Ergebnisse nach operativer Behandlung der radiohumeralen Epikondylopathie.

We examined extent and affection of an assumed neuromuscular transmission disorder by performing a prospective clinical study on 75 patients with therapy-resistant radiohumeral epicondylopathy. Before operation, we electromyographically diagnosed an increased rate of polyphasic potentials of the long wrist extensors as well as a prolonged motor latency of the respective muscles. Corresponding to a hereby implied damage to the distal part of the motor neuron, disordered neuromuscular recruitment combined with a reduced maximum strength and -elasticity could be proven. Both effects were significantly reversible (p < 0.001) through operative intervention. We found a significant correlation (corr < 0.90) between the normalization of the motor latency and increased strength. Subgroups were formed depending on different pre-operative diagnostic efforts and differing redicality regarding the performed soft-tissue operation, thus the clinical validity of the findings diagnosed in the anatomic and neurophysiologic part of the study was additionally examined. It was proven that the failure rate varies between 10% and 30%, depending on the radicality of tenotomy, which could be interpreted as a general indication for complete extensor carpi radialis brevis tendon release. In this connection it is remarkable that the clinical result of an electromyographically localized damage in the area between epicondyle and arcade of Frohse could not be improved through open neurolysis. Dealing with strictures located on the proximal side of the epicondyle on the other hand, this technique seems to play an important role for recurrence prophylaxis.

[Cryotherapy as analgesic technique in direct, postoperative treatment following elective joint replacement]. / Kryotherapie als Analgesietechnik in der direkten, postoperativen Behandlung nach elektivem Gelenkersatz.

The application of crushed ice or hydrogenated silicate, a micro-crystalline substitute has been used as a method to treat posttraumatic and postoperative irritations of the locomotor system for a long time. Closed systems using pumps can be viewed as further development as they enable continuous, water-free cooling of operating areas. The analgetic effect of postoperative cold therapy was evaluated in a prospective clinical trial, including 312 patients after total knee or hip arthroplasty. Conventional cold packs, consisting of microcrystalline silicate were compared to a continuous applicable closed system. Continuous cryotherapy resulted in a depression of skin temperature to 12 degrees C, whereas intermittent cooling only caused a mean temperature decrease of 1 degree C. Clinically continuous cold application leads to a more than 50% decrease of analgetic demands in both, systemic and regional application (p < 0.001). This observation was found in a significant correlation with patient's pain sensation as well as primary range of motion. Intermittent cryotherapy was found to be ineffective in postoperative pain relieve in hip- and adequate in knee arthroplasty patients. We could not report an influence on postoperative blood loss, as discussed in previous reports.

Pathoanatomic findings in radiohumeral epicondylopathy. A combined anatomic and electromyographic study.

Several authors believe that a compression syndrome of the radial nerve or its muscle branches is responsible for the clinical picture of radiohumeral epicondylopathy. Various structural and functional stenoses have been discussed as possible causes. We performed systematic electromyographies (EMGs) on the extensors subdividing from the radial epicondyle and found significant changes (P < 0.05) in 27/51 patients regarding latency, velocity of nerve conduction and rate of polyphasic potentials. Especially affected were the extensor carpi radialis brevis and the extensor digitorum muscle. In order to clarify causal anatomic correlations, we performed a longitudinal and cross-sectional study on a total of 40 arms from cadavers. We found constant variations from the topographic anatomy published in the standard literature which corresponded to the EMG results in the area between the epicondyle and place of entry into the supinator muscle. In addition, we observed a regularly occurring ulnar deviation from the distal part of the extensor carpi radials brevis origin which protrudes over the plane of insertion of the joint extensor tendon aponeurosis and forms in most cases the arcade of Frohse. Because the deep radial branch and its parallel muscular branches cross this part at an obtuse angle, we think that dynamic pressure on a nerve without structural influences is the pathoanatomic result of this heterogeneously interpreted clinical picture.

Diagnostic and therapeutic strategies for the operative treatment of radiohumeral epicondylopathy.

We examined the extent and effect of an assumed neuromuscular transmission disorder by performing a prospective clinical study on 75 patients with therapy-resistant radiohumeral epicondylopathy. Before operating, we diagnosed with electromyography an increased rate of polyphasic potentials of the long wrist extensors as well as a prolonged motor latency of the respective muscles. Disordered neuromuscular recruitment combined with a reduced maximum strength and elasticity corresponding to the suspected damage to the distal part of the motor neuron could be proven. Both effects were significantly reversible (P < 0.001) through operative intervention. We found a significant correlation (> 0.90) between the normalization of the motor latency and increased strength. Subgroups were formed according to different preoperative diagnostic efforts and differing radicality regarding the type of soft-tissue operation performed; thus, the clinical validity of the findings diagnosed in the anatomical/ electrophysiological part of the study was additionally examined. The failure rate varied between 10% and 30%, depending on the radicality of the tenotomy, which could be interpreted as a general indication for a complete extensor carpi radialis brevis tendon release. In this connection it is remarkable that the clinical result of electromyographically localized damage in the area between the epicondyle and arcade of Frohse could not be improved through open neurolysis. Dealing with strictures located on the proximal side of the epicondyle on the other hand, this technique seems to play an important role in the recurrence prophylaxis.

[Effects of continuous cryotherapy on the surgically traumatized musculoskeletal system. Perioperative Cryotherapy Study Group]. / Effekte kontinuierlicher Kryotherapie auf den operativ traumatisierten Bewegungsapparat. Perioperative Kryotherapie-Arbeitsgruppe.

The in-vivo effectiveness of continuous cold pressure therapy was evaluated in 24 patients following elective knee or hip replacement surgery. A cooling of the skin surface down to 8 degrees C resulted in a reduction of the epifascial tissue temperature to 22 degrees C. A significant reduction of subfascial pressure in combination with decreased protein leakage via redovac output were notable. Observing a constant decreased pH-level increased oxygen saturation and reduced drop of base excess were interpreted as signs of reduced enzyme-linked metabolism activity. Clinically these findings were found in correlation to a 50% decrease of postoperative analgetic demands as well as a 20% increased range of motion level.

[Inlay dislocations after primary, cement-free hip joint replacement]. / Inlayluxationen nach primärem, zementfreien Hüftgelenkersatz.

This report deals with diagnostic effort of dislocated acetabular cup inlay in cementless total hip-arthroplasty. The metallic sound caused by collision of the ceramic head and metal acetabular component is documented by CTG. Suggestions of incidence and prevention of later inlay-dislocations during primary implantation are given.