Protein kinase C mediates flow-induced prostaglandin E2 production in osteoblasts

A study was conducted, on 30 human fetuses, of the structures passing through the tympanosquamosal fissure. The tympanosquamosal fissure lies between the middle ear and the temporomandibular region. Meckel's cartilage passes through the tympanosquamosal fissure and continues on into the middle ear with the cartilaginous anlage of the malleus. A tract of fibrous tissue arises from the mesenchyme, located cranial and lateral to Meckel's cartilage, that enters from the posterior area of the temporomandibular joint disc to the middle ear through the tympanosquamosal fissure, and attaches onto the area of continuity of Meckel's cartilage with the malleus. Transformation of Meckel's cartilage into the sphenomandibular ligament and anterior ligament of the malleus determines their continuity through the tympanosquamosal fissure. The posterior fibers of the temporomandibular joint disc giving rise to the discomalleolar ligament insert into the anterior ligament of the malleus.     

Histopathological findings in the proprioception of the shoulder joint

Purpose of this study was the evaluation of distribution and morphology of mechanoreceptors in the glenohumeral joint capsule and rotator cuff in comparison to the coracoacromial ligament by means of specific immunfluorescence microscopy. The complemente joint capsules, rotator cuffs and coracoacromial ligaments of three fresh cadaver shoulder were harvesed. Serial cryostate sections were taken and alternately incubated with antiserum against neurofilament, lamin or myelin of peripheral nerves. The antibody-reaction was visualized with fluorescin lg-G. The nerve endings were photographed and computer-aided 3-dimensional reconstructions were performed. Three types of corpuscular and free nerve endings of different morphology were found in different distributions: whereas the Ruffini corpuscles were much more frequent in the coracoacromial ligament and rotator cuff, Pacini endings were predominantly found in the joint capsule. Generally corpuscular nerve endings were more frequent in the coracoacromial ligament and the rotator cuff than in the antero-inferior capsule and the number of corpuscles increased from medial to lateral within the anterior and inferior parts of the capsule. The dense ligamentous tissue was almost aneural whereas the periarticular fatty or loose connective tissue contained nerve fibres and nerve endings. In view of the results of other experimental and clinical studies the high frequency of Ruffini and Pacini endings in the rotator cuff and coracoacromial ligament suggest, that both are involved in the neurosensory control of glenohumeral stability and subacromial impingement. In contrast our findings in the joint capsule do not clearly prove, that those joint receptors predominantly maintain joint stability.     

Neural structures within the sheep temporomandibular joint

To better understand pathologic processes associated with arthritis of the temporomandibular joint (TMJ), detailed information on the innervation of TMJ tissues in normal as well as arthritic joints is needed. The aim of this study was to describe the normal innervation of the sheep TMJ in preparation for using this animal as a model for the study of the effects of arthritis on joint innervation. The macroscopic and microscopic appearance plus the distribution of neural structures within the TMJ were examined using fluorescence histochemistry (glyoxylic acid), immunohistochemistry (calcitonin gene-related peptide), silver, and gold chloride techniques. Joints from 10 mature merino sheep were studied. Calcitonin gene-related peptide-immunoreactive nerve fibers were found in the capsule and the synovial membrane, but not in the disc. Nerve bundles and single nerve fibers in the capsule, synovial membrane, and the peripheral 2 to 3 mm of the disc were stained by glyoxylic acid. Ruffini, paciniform-type, and Golgi organ nerve endings plus free nerve endings were located in the capsule, with the highest density of nerve endings occurring at the site of attachment of the disc to the capsule. The highest density of neural structures (using gold chloride) was in the posterior part of the joint. The highest density of autonomic fibers (using glyoxylic acid) was in the anterior capsule. The highest density of sensory fibers (using calcitonin gene-related peptide) was in the synovial and subsynovial tissues of the anterior capsule. These results confirm the existence of autonomic and sensory nerves in the capsule, synovial membrane, and peripheral disc in healthy adult sheep.     

The TMJ-ear connection

This article documents the existence of three structures that traverse through the petrotympanic fissure. These structures are the mandibular malleolar ligament, the chorda tympani nerve and the anterior tympanic artery. The mandibular malleolar ligament or the disk-malleolar ligament originates on the anterior process of the mallous. It traverses through the petro-tympanic fissure and attaches to the posterior portion of the capsule and disk of the temporomandibular joint. The chorda tympani nerve supplies sensory feeling to the posterior two thirds of the tongue. The anterior tympanic artery supplies blood to the area of the tympanic membrane. Clinical experience with implants that impinge or cover ear problems and other symptoms. Removal of these implants and placements with devices that do not cover these structures often relieve these symptoms.     

Diagnosis and therapy of the rupture of both cruciate ligaments, the medial collateral ligament and abscission of both menisci in a ram. A case report

This report describes the case history of a 1.5-year-old ram admitted to the Clinic for Food Animals and Horses, University of Berne, Switzerland, because of an acute severe lameness of the left rear limb. Clinical and radiographic examination revealed disruption of the stifle joint with rupture of both cruciate ligaments, the medial collateral ligament, and disruption of both menisci from their attachments. The ruptured ligaments were replaced by synthetic ligament prostheses. Long-term examination at 12 months after implantation revealed slight instability of the stifle joint, caused by degeneration of the medial meniscus, and signs of arthrosis deformans. The new formed periarticular connective tissue contributed to the stability of the stifle joint, so that a good functional result was achieved. Necropsy findings at 14 months after implantation confirmed that the synthetic ligament prostheses were intact and the medial meniscus was detached from its insertion and incorporated into the joint capsule. At microscopic examination of the synthetic band prosthesis, ingrowth of collagen and fibrous tissue was evident.     

Contribution of the anterolateral joint capsule to the mechanical stability of the ankle

Published reports describe the clinical efficacy of modified Brostrom anatomic repairs, surgical procedures that involve repair and fortification of the lateral capsuloligamentous complex of the ankle for patients suffering from chronic lateral instability of this joint. A cadaveric serial sectioning study of the anterior talofibular ligament, the calcaneofibular ligament, and the remainder of the anterolateral joint capsule was completed to quantitate the contribution of the superior portion of the anterolateral joint capsule, independent of the other two structures, to the overall mechanical stability of the lateral ankle. Using 20 fresh frozen specimens, talar tilt and anterior drawer stress radiographs were taken before and after sectioning these anatomic structures in an order established by one of two protocols. Sectioning of the superior anterolateral joint capsule caused 17% to 18% of the total displacement in a Grade II sprain simulation and 29% to 33% of the total displacement in a Grade III sprain simulation. This work suggests that disruption of the segment of ankle joint capsule superior to the anterior talofibular ligament creates approximately 30% of the overall laxity encountered in a Grade III inversion sprain, substantiating the principle of restoring the integrity of the entire anterolateral joint capsule when operating on a chronically unstable ankle.     

Role of medical capsule and transverse metatarsal ligament in hallux valgus deformity

The role of the medial capsule and transverse metatarsal ligament in hallux valgus deformity including stability of the first metatarsophalangeal and adjacent joints was investigated in vitro. The three-dimensional positions of the proximal phalanx, first metatarsal, and second metatarsal before and after sectioning the medial capsule and metatarsal ligament were measured using a magnetic tracking system. Valgus deformity of the hallux increased with medial capsule sectioning an average of 22.3 degrees +/- 6 degrees. Valgus deformity of the hallux increased with medial capsule and metatarsal ligament sectioning an average of 27.4 degrees +/- 9.1 degrees. Valgus deformity of the hallux did not change significantly after sectioning the metatarsal ligament only. No significant changes were found in varus and eversion of the first metatarsal, in valgus of the second metatarsal, in the distance between first and second metatarsal heads after sectioning the medial capsule, or in the metatarsal ligament. This study shows the importance of the medial capsule in hallux valgus deformity. The transverse ligament did not contribute substantially to cause the deformity.     

A radiological sign of entrapment of the median nerve in the elbow joint after posterior dislocation. A report of two cases

Two boys with entrapment of the median nerve in the elbow joint after closed reduction of a posterior dislocation with fracture of the medial epicondyle showed a characteristic radiological sign in the anteroposterior radiograph after two to three months. The sign was a depression in the cortex on the ulnar side of the distal humeral metaphysis, with interruption of the local periosteal reaction. At operation in both patients the depression was found to correspond with the place where the median nerve reached the posterior surface of the humerus. Radiographs taken after transverse section of the nerve above and below the joint capsule and end-to-end suture showed gradual disappearance of the cortical depression.     

The hypomobile temporomandibular joint

The hypomobile (restricted) temporomandibular joint (TMJ) is usually caused by a restricted joint capsule or by an anteriorly displaced disk. Here, painful unilateral hypomobility (19 mm jaw opening), with normal disk position, caused by voluntary immobilization after a dental procedure, was the presenting symptom. Management included inflammation control, TMJ manipulation (mobilization), and lateral pterygoid muscle relaxation. Inflammation and pain were alleviated by nonsteroidal anti-inflammatory drugs (NSAIDs) and local TMJ ice massage. TMJ mobilization was performed at every visit, to tear joint capsule adhesions and to realign collagen fibers. Exercise consisted mainly of resistive opening (the patient resists an upward force applied to the chin), with the jaw maintained at full opening. This produced lateral pterygoid muscle relaxation at full length, aiding in the restoration of a pain-free 44 mm opening.     

Effect of ethanol on glycide, lipid, and protein components in the liver and blood of rats (author''s transl)

The hindlimbs of 3 ponies and 3 horses were dissected. The hip joint capsule was found to receive articular nerve fibers from the femoral, obturator, cranial gluteal, and sciatic nerves. The nerve fibers were distributed to the fibrous joint capsule and associated capsular ligaments. The stifle joint capsule was found to receive articular branches from the femoral, saphenous, obturator, common peroneal, and tibial nerves. The fibers terminated in the joint capsule, fat pad, patellar and collateral ligaments, and the internally situated meniscal and cruciate ligaments.     

Dynamic magnetic resonance of the temporomandibular joint. Observations and findings

Condylar movements can be executed only if the TMJ morphology can satisfy functional needs of the masticatory apparatus. Articular components have to be in good relation with dento-skeletal functional anatomy: if this does not occur, mandibular dynamics may establish some functional stresses on the condylar head and the articular eminence. These overloaded structures and particularly their functional surfaces react to this situation to be remodelling and deformation of the articular cavity. In our work we have used a new method to analyse condylar dynamics using MRI. The reconstruction of mandibular movements, using this instrumentation, permits to make some useful observations on the functional capability of TMJ to adjust itself to different maxillofacial morphologies and, consequently, how this joint can fall in a dysfunctional and pathological condition.     

Support of the talus: a biomechanical investigation of the contributions of the talonavicular and talocalcaneal joints, and the superomedial calcaneonavicular ligament

The goal of this study was to determine the magnitude of force transmission to the talus by its inferior articulations to provide insight into mechanisms involving acquired deformities of the hindfoot. Cadaver feet were mounted in a loading apparatus that applied axial force through the tibia and fibula as well as tensile loading of the tendons of extrinsic musculature. This also permitted positioning of the tibia in the sagittal plane. Eighteen specimens were tested in three selected positions of the gait cycle. In one series, pressure-sensitive film was inserted into the posterior and anteromedial facets of the talocalcaneal joint as well as into the talonavicular joint. In a second series, film was inserted between the talar head and the superomedial calcaneonavicular ligament. In stance position, the specimens were also tested without posterior tibial tendon (PTT) tension. Contact areas and force transmitted across the articulations were greatest in near toe-off position, in the posterior facet of the talocalcaneal joint. The talonavicular joint, the anteromedial facet of the talocalcaneal joint, and the calcaneonavicular ligament articulation showed sequentially decreasing amounts of contact area and force transmission. Mean pressures were similar across all articulations, except in the posterior facet in near toe-off position. From heel-strike to stance, to near toe-off, a trend to increasing contact area and force was noted. No difference in contact characteristics was found in the calcaneonavicular ligament articulation after PTT release. The contact force of the calcaneonavicular ligament against the talus was found to be much smaller than those of other talar articulations; however, its medially oriented direction must contribute to stabilization of the head of the talus against medial displacement. Loss of PTT tension was not found to alter the contact forces acting at the talar head in this model, which might indicate that it shares its talar stabilizing function with other structures.     

Noise, physiology, and human performance: the potential role of effort

The equine fetlock joint cavity shows ten pouches. The dorsal recess, which is oriented to the proximal side, is separated from those three pouches, which show to the distal direction, by several capsular folds. These folds are documented by means of sagittal sections through the fetlock joint. A medial/lateral recess is covered by the deep part of the collateral ligament of the fetlock joint. The collateral ligaments as well as the sesamoidean collateral ligaments are closely connected with the joint capsule, from which two capsular folds are separated. Between the part of the sesamoidean collateral ligament, that inserts to the metacarpus/metatarsus and the part that inserts to the proximal phalanx, the fetlock joint cavity pouches as Recessus palmaris/plantaris distalis medialis/lateralis. The palmar/plantar distal pouch, which lies in the median line, is covered by the Ligamentum sesamoideum rectum. This recess is narrowed down by the cruciated sesamoidean ligaments. The dominant palmar/plantar proximal recess is subdivided into several small pouches by strings or bands of the joint capsule, which can already be seen with an unaided eye.     

Indications for surgical treatment of tibial condyle fractures

The residual radioanatomic changes influencing the functional, subjective, and clinical outcome of 131 tibial condyle fractures were studied. Clinical function was found to deteriorate rapidly with increasing values of residual medial tilt of the tibial plateau, whereas lateral tilt of the plateau was well tolerated up to 5 degrees. Articular step-off up to 3 mm and condylar widening up to 5 mm had no adverse effects. Seventy percent of knees with moderate or severe instability were functionally unacceptable. It was concluded that a medial unicondylar fracture with any displacement, and all medially tilted bicondylar fractures, should be operated upon. In fracture of the lateral condyle, open reduction and internal fixation is indicated when lateral tilt or valgus malalignment exceeds 5 degrees, articular step-off exceeds 3 mm, or condylar widening exceeds 5 mm. The same limits apply to laterally tilted bicondylar fractures, provided that the medial condyle is undisplaced. Any displacement seen in the axial bicondylar fracture is an indication for surgical treatment. If there is any mediolateral instability in the extended knee joint after rigid internal fixation, repair of a collateral ligament should be considered. An avulsed anterior cruciate ligament should be fixed, if pathologic laxity exists, but the torn ligament can be ignored and reconstructed later if needed.     

Surgical anatomy of the infratemporal fossa: the styloid diaphragm revisited

INTRODUCTION: The infratemporal fossa (ITF) gives passage to most major cerebral vessels and cranial nerves. Dissection of the ITF is essential in many of the lateral cranial base approaches and in exposure of the high cervical internal carotid artery (ICA). We reviewed the surgical anatomy of this region. METHODS: Direct foraminal measurements were made in seven dry skulls (14 sides), and the relationship of these foramina to each other and various landmarks were determined. Ten ITF dissections were performed using a preauricular subtemporal-infratemporal approach. Preliminary dissections of the extracranial great vessels and structures larger than 1 cm were performed using standard macroscopic surgical techniques. Dissection of all structures less than 1 cm was conducted using microsurgical techniques and instruments, including the operating microscope. The anatomic relationships of the muscles, nerves, arteries, and veins were carefully recorded, with special emphasis regarding the relationship of these structures to the styloid diaphragm. The dissection was purely extradural. RESULTS: The styloid diaphragm was identified in all specimens. It divides the ITF into the prestyloid region and the retrostyloid region. The prestyloid region contains the parotid gland and associated structures, including the facial nerve and external carotid artery. The retrostyloid region contains major vascular structures (ICA, internal jugular vein) and the initial exocranial portion of the lower Cranial Nerves IX through XII. Landmarks were identified for the different cranial nerves. The bifurcation of the main trunk of the facial nerve was an average of 21 mm medial to the cartilaginous pointer and an average of 31 mm medial to the tragus of the ear. The glossopharyngeal nerve was found posterior and lateral to stylopharyngeus muscle in nine cases and medial in only one. The vagus nerve was consistently found in the angle formed posteriorly by the ICA and the internal jugular vein. The spinal accessory nerve crossed anterior to the internal jugular vein in five cases and posterior in another five cases. It could be located as it entered the medial surface of the sternocleidomastoid muscle 28 mm (mean) below the mastoid tip. The hypoglossal nerve was most consistently identified as it crossed under the sternocleidomastoid branch of the occipital artery 25 mm posterior to the angle of the mandible and 52 mm anterior and inferior to the mastoid tip. CONCLUSION: The styloid diaphragm divides the ITF into prestyloid and retrostyloid regions and covers the high cervical ICA. Using landmarks for the exocranial portion of the lower cranial nerves is useful it identifying them and avoiding injury during approaches to the high cervical ICA, the upper cervical spine, and the ITF.     

The sensory innervation of the hip joint--an anatomical study

Typically obturator nerve blockade is used to relieve hip pain. It sometimes only has a minor effect in resolving symptoms. This clinical observation led us to examine comprehensively the sensory nerve innervation of formalin-fixed hip joint capsules. Following macroscopic preparation, the area of the hip joint capsule was inspected with the aid of an operating microscope. We discovered a separation between the anterior and posterior sensory innervation of the hip joint capsule. The anteromedial innervation was determined by the articular branches of the obturator n. Additionally, the anterior hip joint capsule was innervated by sensory articular branches from the femoral n. In the posterior part we found articular branches from the sciatic n., which in addition to the articular branches from the nerves to the quadratus femoris m., innervate the postero-medial section of the hip joint capsule. Moreover, articular branches of the superior gluteal n. were found, which innervate the posterolateral section of the hip joint capsule. This anatomical study demonstrates that the obturator n. block is insufficient for the treatment of hip pain. Further investigations will determine if these nn. can be reached percutaneously. Effective neural blockade of the hip joint must include the femoral n., the sciatic n. and the superior gluteal n.     

The intercarpal ligaments of the equine midcarpal joint, Part 1: The anatomy of the palmar and dorsomedial intercarpal ligaments of the midcarpal joint

OBJECTIVE: To describe in detail the structure of the medial palmar intercarpal ligament (MPICL), the lateral palmar intercarpal ligament (LPICL), and a dorsomedial intercarpal ligament (DMICL) of the equine midcarpal joint. STUDY DESIGN: Dissections of equine midcarpal joints. ANIMALS AND SAMPLE POPULATION: Ten carpal joints from eight thoroughbred horses. METHODS: Detailed dissections of the midcarpal joint were performed, with particular attention paid to the MPICL, the LPICL, and the DMICL. The attachments and dimensions of these structures were recorded, as well as their behavior during joint movement. RESULTS: The DMICL arose from the dorsomedial surface of the radial carpal bone (CR) and coursed palmarodistally to insert on the dorsomedial aspect of the second carpal bone (C2). The LPICL attached proximally predominantly on the distal part of the palmaromedial surface of the ulnar carpal bone (CU). From here the ligament coursed distomedially and slightly palmarly to the proximal palmarolateral surface of the third carpal bone (C3). The structure of the MPICL was complex. It attached proximally to the distolateral surface of the CR and distally to the proximal palmaromedial surface of C3, and the proximal palmarolateral aspect of the C2. It could be divided into four fiber bundles in all carpi. The predominant direction of fibers was dorsoproximal to palmarodistal, whereas the palmaromedial bundle coursed palmaroproximal to dorsodistal. CONCLUSIONS: The orientation of their fibers indicate that the MPICL and DMICL primarily resist dorsomedial displacement of CR, whereas the LPICL resists dorsolateral displacement of the CU and intermediate carpal bone. CLINICAL RELEVANCE: An understanding of the structure of the intercarpal ligaments of the midcarpal joint is important in interpreting their function and the reasons for damage to their structure.     

Medial soft tissue restraints in lateral patellar instability and repair

This study was undertaken to evaluate the medial ligamentous stabilizers of the patella in restraining lateral displacement and to assess their relative contribution after individual repair. Seventeen fresh frozen human anatomic specimen knee joints were studied. The specimens were loaded onto a testing instrument that was designed to measure the compliance of the medial and lateral patellar restraints in the coronal plane. Two different cutting and repair sequences were used to test the individual contributions of the patellar ligaments. The medial patellofemoral ligament was found to be the major medial ligamentous stabilizer of the patella. Isolated release resulted in a 50% increase in lateral displacement, and isolated repair restored balance to the patella. In addition, the patellotibial and patellomeniscal ligament complex played an important secondary role in restraining lateral patellar displacement. Isolated repair of these ligaments restored balance to near normal levels. The medial patellofemoral retinaculum played only a minor role in patellofemoral instability. Proximal realignment or medial ligament repair for patellofemoral instability specifically should address repair of the deep layers that contain the restraints to lateral patellar displacement. Failure to include these structures in repair, especially of the medial patellofemoral ligament, may lead to persistent or recurrent instability.     

Airway obstruction caused by an oleothorax

PURPOSE: This article describes the possible role of various peptides in producing pain and inflammation in the temporomandibular joint (TMJ). MATERIAL AND METHODS: Current research findings on the spectrophotometric quantification of TMJ synovial fluid for neuropeptide Y (NPY), serotonin (5HT), and interleukin-1beta (IL-1beta) are presented. FINDINGS: NPY was found in high levels in the synovial fluid of arthritic TMJs with resting pain, and serotonin (5-HT) was found in patients with pain perceived on mandibular movement. These pain-related mediators were also associated with restricted mandibular mobility. Interleukin-1beta (IL-1beta) was found to be strongly associated with hyperalgesia over the TMJ as well as resting pain. Anterior open bite as a clinical sign of joint destruction was found to be associated with high levels of NPY and IL-1beta in the synovial fluid. IL-1beta was also related to the radiographic signs of joint destruction. CONCLUSIONS: Interaction between the peripheral nervous system (sensory and sympathetic nerves) and the immune system is probably of importance for the modulation of pain and inflammation in the TMJ, but this subject has to be investigated further with experimental clinical studies.     

Microscopic evaluation of the placenta of women from an ecologically threatened area (P?ock). Part II

This paper gives an overview of the sonographic possibilities to examine the canine stifle joint with rupture of the cruciate ligament. Sonographic examination was performed in 100 surgical patients because of a lesion of the joint. Ultrasound sections are presented with corresponding sonographical findings and pathological changes. For stifle joint, a linear transducer with 7.5 Mhz proved to be useful. Both the lateral and medial meniscus could be inspected, as well as injuries of the menisci. As an indirect sign to a lesion, effusions of the joint were demonstrable quite sensitively. The cruciate ligaments could not be investigated correctly with ultrasound. Ultrasonography is used to investigate the soft tissue structures as a completion of the radiological examination. The scanning diagnostic technique is practicable with a low technical expenditure, it is not stressful for the patient and can be repeated for therapy controls. Disadvantageous is that ultrasound is prone to artefacts, caused by the thinness of the structures examined.