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Glenohumeral joint instability and dislocations are common diagnoses seen by physicians. There are many different pathologic etiologies for these conditions. A thorough understanding of the history,physical examination, pathoanatomy, and classification systems is required to make an accurate diagnosis. With the appropriate diagnosis, the clinician can choose the correct treatment and improve the patient's outcome.
The anterior drawer was evaluated sonographically under standard conditions (150 N load, 7.5 MHz linear scanner) in 95 patients with severe ankle sprain. A simple geometric construct of subsidiary lines set up with the help of a goniometer on the videoprints (enlargement 1.5 X) enabled a standardized interpretation of the anterior drawer (pathologic > or = 3 mm). Thus, the definition of poorly reproducible reference points for sonographic measurements became avoidable. In 60 patients a rupture of the lateral ankle ligaments was diagnosed, in 35 patients the findings were recorded as severe ankle sprains without ligament rupture. Compared with the radiological anterior drawer and talar tilt, the dynamic sonographic measurement of the anterior drawer showed the better values from the aspects of sensitivity, specificity and accuracy (> or = 0.93). In our own practice sonographic measurement of anterior drawer has replaced stress radiograms in diagnosis of ankle joint instabilities after severe ankle sprains.
Glenohumeral joint instability is a fairly common clinical disorder in athletes, especially in sports that involve the throwing motion. The direction of shoulder instability can be anterior, inferior, posterior, or multidirectional. The cause can be trauma, congenital laxity, or voluntary muscle action. Normal shoulders that have been disrupted by injury respond well to surgical correction. Shoulders that have inherently lax supporting structures, as found in patients with atraumatic and voluntary dislocation, have less consistent success with surgical repair. A common condition encountered in the shoulder of a throwing arm is anterior subluxation, which can be diagnosed by the positive apprehension sign and confirmed by arthroscopy. A torn glenoid labrum is a common injury also. Improvement in the diagnosis and treatment of shoulder disorders has been made recently by arthroscopy which allows direct visualization of the joint; many conditions can now be corrected by means of arthroscopic surgery. Radiographic techniques have also been improved.
Chronic instability of the knee joint is a serious problem for the affected patient and the attending physician. Diagnosis must reveal which structures of the soft knee are insufficient. We use as a basis in particular a detailed clinical examination which frequently must be made under short-term general anaesthesia. As to auxiliary examination methods, we recommend X-rays in forced positions, possibly arthroscopy. Defects of the cruciate ligaments can be evaluated well also by means of computed tomography. Operation should be indicated carefully. We consider the extent of the patient's complaints, the ability of dynamic compensation of the instability, the presence of exudates, haematomas, signs of arthritis, locomotor restrictions and, last not least, also the assumed ability of the patient to cooperate in rehabilitation. In surgical treatment of instabilities it is necessary to respect carefully biomechanical principles of the function of the knee joint. In prostheses of the cruciate ligaments we prefer direct reconstruction with an autologous graft to extraarticular operations. It seems that in older patients also reconstruction with synthetic ligaments will be feasible.
This study evaluated the effect of notchplasty (enlargement of the intercondylar fossa) in stable and unstable canine stifles. Bilateral notchplasty and unilateral cranial cruciate ligament (CrCL) transection were performed in 6 dogs. Exercise, consisting of walking 1.5 miles three times a week, began 1 month after surgery and continued until euthanasia 6 months after surgery. Evaluation methods included orthopedic examination, serial radiographs, thin section radiography, histopathology, and gross pathology. Notchplasty in the stable stifle did not cause lameness beyond 3 weeks, joint instability, or degenerative joint disease. In the stable stifle, smooth resurfacing of the notchplasty site with fibrous and osseous tissue occurred. Stifles with notchplasty and CrCL transection exhibited persistent lameness, instability, and degenerative joint disease. In CrCL deficient stifles osteophytes formed within the notchplasty site, resulting in a rough surface. Our observations indicated significant refilling in notchplasties of both stable and unstable stifles (P < .05). However, the intercondylar fossa (ICF) width 6 months after notchplasty was significantly smaller in unstable stifles compared with stable stifles (P < .05) indicating that greater refilling of the notchplasties occurred in the unstable stifles. In clinical cases, notchplasty should be larger than the desired final result to accomodate the partial refilling that occurs even in stable stifles.
This study describes the titanium ComPact UniLock 2.0/2.4 locking plate system (Stratec Medical, Oberdorf, Switzerland) and reports its application in nine selected clinical cases. The system was found useful for a variety of indications. Three categories of clinical applications are illustrated. They include (a) long bone fractures, (b) cervical spinal fractures and instabilities and (c) joint instabilities and luxations. A brief introduction to the system has already been published
In the article is presented the analysis of treatment of 32 patients with shoulder joint instability. There have been studied the outcomes of treatment after the arm "suspension" operations, interventions at the anterior region of an articulation, derotational osteotomies of an arm. There have been considered the problems of etiopathogenesis of shoulder joint instability. There have been analyzed the peculiarities of the tactical approach to the treatment of patients with shoulder joint instability. There is presented the principled position of the authors' approach to the selection of pathogenetically substantiated method of the habitual shoulder slip operative treatment.
Ligament insufficiency due to athletic injury is widely recognized and reported as an etiological factor in knee joint instability. It was recognized that a patient presenting with knee joint instability due to past hockey injury to the anterior cruciate ligament, subsequently verified surgically, was able to voluntarily and actively perform the pivot shift maneuver with his knee as a result of his anterolateral rotatory instability. During a subsequent 6 month period, three other patients with similar anterior cruciate deficiencies presented with this same active pivot shift maneuver phenomenon. A study was designed to determine the active muscle or muscles involved in this abnormal active motion in the knee joint with anterolateral rotatory instability. Electromyographic studies with needle electrodes were conducted on a variety of muscles in four subjects presenting with the instability. Results indicated that the popliteus muscle plays a major role in the active performance of the pivot shift maneuver.
Functional instability, i.e. recurrent sprains or a feeling of giving way in the joint, is common after ankle sprain. Using stabilometry, an objective and quantitative method for studying postural control, we earlier showed that soccer players with pathological stabilometric results are at risk for ankle joint injury. In the present study we found that the ability to maintain postural equilibrium as demonstrated by stabilometry was reduced among players with functional instability, but was not affected by mechanical instability. The results indicate that coordination and postural control are important for functional instability of the ankle.
Carpal instabilities are caused by traumatic injuries to the bones and ligaments of the wrist joint, or by chronic overstretching of the ligaments due to inflammatory or degenerative diseases; an important factor in their development is the anatomical shape of the bones and their articular surfaces. According to their location, they are classified as radial (lateral), medial, and proximal carpal instabilities. The different types are described, especially with regard to their radiological signs; static and dynamic instabilities are distinguished. The common therapeutic strategies are reconstruction of ligaments, intercarpal arthrodesis, or correction osteotomy of the radius.
While morphologic and biochemical aspects of degenerative joint disease (osteoarthritis [OA]) have been elucidated by numerous studies, the molecular mechanisms underlying the progressive loss of articular cartilage during OA development remain largely unknown. The main focus of the present study was to gain more insight into molecular changes during the very early stages of mechanically induced cartilage degeneration and to relate molecular alterations to histological changes at distinct localizations of the joint. Studies on human articular cartilage are hampered by the difficulty of obtaining normal tissue and early-stage OA tissue, and they allow no progressive follow-up. An experimental OA model in dogs with a slow natural history of OA (Pond-Nuki model) was therefore chosen. Anterior cruciate ligament transection (ACLT) was performed on 24 skeletally mature dogs to induce joint instability resulting in OA. Samples were taken from different joint areas after 6, 12, 24 and 48 weeks, and gene expression levels of common cartilage molecules were quantified in relation to the histological grading (modified Mankin score) of adjacent tissue. Histological changes reflected early progressive degenerative OA. Soon after ACLT, chondrocytes responded to the altered mechanical conditions by significant and stable elevation of collagen type II, collagen type I and YKL40 expression, which persisted throughout the study. In contrast to the mild to moderate histological alterations, these molecular changes were not progressive and were independent of the joint localization (tibia, femur, lateral, medial) and the extent of matrix degeneration. MMP13 remained unaltered until 24 weeks, and aggrecan and tenascinC remained unaltered until 48 weeks after ACLT. These findings indicate that elevated collagen type II, collagen type I and YKL40 mRNA expression levels are early and sensitive measures of ACLT-induced joint instability independent of a certain grade of morphological cartilage degeneration. A second phase of molecular changes in OA may begin around 48 weeks after ACLT with altered expression of further genes, such as MMP13, aggrecan and tenascin. Molecular changes observed in the present study suggest that dog cartilage responds to degenerative conditions by regulating the same genes in a similar direction as that observed for chondrocytes in late human OA.
Twenty cats with a chronic progressive polyarthritis were studied. The disorder occurred exclusively in male cats, and all but six of the cats were between 1.5 and 5.0 years of age. There were two forms of the disease as determined by radiographic changes: joint instability and deformity, and clinical course. The most prevalent form of the disease was characterized by osteopenia and periosteal new bone formation surrounding affected joints. Marginal periarticular erosions and collapse of the joint spaces with fibrous ankylosis occurred with time, but joint instability and deformities were not seen. The second form of the disease was characterized by severe subchondral marginal erosions, joint instability, and deformities. The periosteal proliferative form resembled Reiter's arthritis of man, and the deforming type resembled human rheumatoid arthritis. The disease began as tenosynovitis and synovitis, with subsequent changes in the articular cartilage and periosteal bone. Histopathologic changes in these cats were similar to those occurring in both chronic Reiter's and rheumatoid arthritis of man. Chronic progressive polyarthritis of cats was not caused by identifiable bacteria or mycoplasma, but was etiologically linked to feline leukemia virus (FeLV) and feline syncytia-forming virus (FeSFV) infections. The FeSFV was isolated from the blood or was detected by a serologic test in all of the cats with the disease, whereas FeLV was isolated or identified by immunofluorescence technique in 60% of the cats. The arthritis could not be reproduced by inoculation of cell-free cynovial tissue from diseased cats or with tissue culture fluid containing FeSFV and FeLV isolates. It was postulated that arthritis was an uncommon manifestation of FeSFV infection that occurred in predisposed male cats. Feline leukemia virus may not have been directly involved in the disease, but may have acted in some way to potentiate the pathogenic effects of FeSFV.
OBJECTIVE: The frequently used anterior cruciate ligament transection (ACLT) model of osteoarthritis (OA) in the dog, makes use of a permanent trigger (joint instability) for inducing degenerative changes. The present study evaluates a canine model of degenerative cartilage damage, mimicking OA, which is induced without making use of permanent joint instability. METHODS: The articular cartilage of the weight-bearing areas of the femoral condyles in one knee of ten beagle dogs was damaged by making grooves, without damaging the subchondral bone. Surgery was followed by 10 weeks intensified loading of the affected joint. Subsequently, joint damage and inflammation were evaluated. The effects were compared with those of the ACLT model. RESULTS: Histological analysis showed chondrocyte clusters around cartilage lesions and moderate loss of proteoglycans in the 'groove' model. Synovial inflammation was mild. Biochemical analysis of cartilage showed changes in matrix proteoglycan turnover, proteoglycan content, and collagen damage, all characteristics of OA. Synovial fluid MMP-1, -3 and -13 activity was enhanced. Changes were found in condyles and plateau, were similar for all animals tested, and were similar to the changes observed in the ACLT model. CONCLUSION: The presently described canine 'groove' model shows characteristics identical to those seen in the ACLT model but differs in a way that the changes are induced without joint instability. The latter is expected to make the 'groove' model more sensitive to treatment.
Intra- and extra-articular methods of cruciate ligament substitution are available for treating old anteromedial knee-joint instability. Twelve patients with intra-articular cruciate ligament substitution (median third of the patellar ligaments as free transplant) and 24 patients with extra-articular cruicate ligament substitution (operation according to Nciholas) were examined with particular reference to improved stability as follow-up examinations, the results being subjected to comparative evaluation. Intra-artricular cruciate ligament substitution reduces or eliminates the pre-operative instability of the joint which is due to insufficiency of the cruciate liagment, whereas the extra-articular cruciate ligament substitution produces a significantly more frequent reduction of elimination of the instability of the valgus position and of the anteromedial instability. The combination of both methods to remove anteromedial instability of the knee joint may seem a very useful solution of the problem, but it should be limited to a restricted group of patients because it involves also contain disadvantages which make it unsuitable for indiscriminate application.
Recurrent glenohumeral joint instability is a common orthopaedic problem. One possible cause of this repeated instability is a lack of neuromuscular control and kinaesthetic sense of the glenohumeral joint. The purpose of this study was to determine whether there is a deficit in joint proprioception in subjects with recurrent anterior glenohumeral instability as compared with individuals with no previous shoulder pathology. Subjects were asked to generate pointing movements with their uninjured limb and to match this limb position with the injured limb. Movements of the pointing limb were measured with an optoelectric three-dimensional movement analysis system. These movements were performed in three conditions: 1) with full vision, 2) without vision, and 3) without vision with vibration to the posterior deltoid muscle. For the temporal and spatial measures, there were no significant differences between the control and shoulder instability groups. However, the kinematic data describing arm trajectory formation showed a performance decrement in the no vision with vibration condition for the subjects in the shoulder instability group, suggesting that they suffer from a proprioceptive deficit.
1. The relationship between joint damage, quadriceps weakness and arthrogenic muscle inhibition was investigated in eight patients who had sustained extensive traumatic knee injury. Isometric and isokinetic quadriceps and hamstring voluntary strength, and quadriceps arthrogenic muscle inhibition during isometric contractions, were measured before and after 4 weeks (approximately 100 h) of intensive rehabilitation. 2. Compared with the uninjured leg, before rehabilitation the injured leg had larger amounts of quadriceps arthrogenic muscle inhibition (P < 0.025), quadriceps (P < 0.0001) and hamstring (P < 0.0001) weakness and severe functional joint instability. There was a negative correlation between the amount of arthrogenic muscle inhibition and quadriceps voluntary contraction force (P < 0.025). 3. After rehabilitation in the injured leg there were small hamstring strength increases (P < 0.05-0.025), but no overall significant quadricep strength increase. Arthrogenic muscle inhibition was statistically unchanged. Severe functional joint instability was still reported by all patients. 4. Previous studies have shown that minimal joint damage evokes relatively less arthrogenic muscle inhibition that does not impede rehabilitation. These data indicate that greater joint damage is associated with greater arthrogenic muscle inhibition, quadriceps weakness and joint instability. Furthermore, intensive rehabilitation had little affect on either quadriceps arthrogenic muscle inhibition or atrophy.
UNLABELLED: The aim of this study was to evaluate the frequency and type of hip-joint instability and the frequency of hip dislocation requiring treatment in neonates who had been lying in the breech presentation and were delivered vaginally after an external version or by caesarean section, and to compare them with neonates who were naturally in the vertex presentation. Breech presentations without ongoing labour were subjected to an attempted external version and, in cases where this proved unsuccessful or where labour had started, to deliver by caesarean section. None of the breech presentations was vaginally delivered. The anterior-dynamic ultrasound method was used to assess the hip-joint status of the neonates. Out of 6,571 foetuses, 257 were in breech presentation after 36 wk of pregnancy. Sixty-two were vaginally delivered following an external version to vertex presentation and 195 were delivered by caesarean section, 75 of these following unsuccessful attempts to perform a version. Treatment for congenital hip-joint dislocation was performed on 0.2%. Out of the breech presentations, 1.0% of those delivered by caesarean section were treated, while in those with vaginal delivery following an external version the treatment frequency was 3.2%. No case of late diagnosed hip dislocation was recorded. Significant differences in frequency of hip-joint instability and treatment were found between (i) neonates delivered in breech presentation and those delivered with vertex presentation, (ii) infants delivered in vertex presentation, naturally or after successful version, and (iii) those delivered by caesarean section with or without attempted external version and those delivered with vortex presentation. CONCLUSION: Breech presentation predisposes to increased hip instability. The instability is present prior to delivery and is certainly not a primary result of delivery forces. Both breech and vertex presentations following an external or spontaneous version should be considered as risk factors for neonatal hip instability.
In the young throwing athlete with shoulder pain, it is essential to recognize that glenohumeral joint instability (occult subluxation, rather than impingement) is the primary underlying pathology. Fortunately, conservative management is effective in most chronic overuse injuries. For those athletes with continued symptoms, surgical intervention may become necessary. The anterior capsulolabral reconstruction addresses the problem of glenohumeral joint instability by correcting the capsular redundancy, labrum damage, or both. The authors believe this most recent surgical technique and postoperative rehabilitation program has resulted in a significant improvement in our ability to more predictably and successfully return these athletes to prior competitive levels.