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PubMed1991

Posterolateral rotatory instability of the elbow.

Recurrent posterolateral rotatory instability of the elbow is an apparently undescribed clinical condition that is difficult to diagnose. We treated five patients, ranging in age from five to forty years, who had such a lesion and in whom the instability could be demonstrated only by what we call the posterolateral rotatory-instability test. This test involves supination of the forearm and application of a valgus moment and an axial compression force to the elbow while it is flexed from full extension. The elbow is reduced in full extension and must be subluxated as it is flexed in order to obtain a positive test result (a sudden reduction of the subluxation). Flexion of more than about 40 degrees produces a sudden palpable and visible reduction of the radiohumeral joint. The elbow does not subluxate without provocation. The cause for this condition, we think, is laxity of the ulnar part of the lateral collateral ligament, which allows a transient rotatory subluxation of the ulnohumeral joint and a secondary dislocation of the radiohumeral joint. The annular ligament remains intact, so the radio-ulnar joint does not dislocate. Operative repair of the lax ulnar part of the lateral collateral ligament eliminated the posterolateral rotatory instability, as revealed intraoperatively in our five patients.

Adult↗
PubMed1990

[Restorative-reconstructive surgery of the bursal-ligamentous apparatus in chronic lateral instability of the knee joint].

Restorative-reconstruction operations for treatment of chronic lateral instability of knee joint have been worked out. Chronic lateral anterior varus instability is eliminated by restoration of anatomy and biomechanics of anterior cruciate ligament and restructuring of peripheral part of the bursal-ligamentous apparatus by means of creation of fibular lateral ligament and 3 derotators (1 active and 2 passive ones). This operation is indicated as well in case of grave anterolateral instability. Instability of posterior types is treated by reconstruction of precise structure and function of posterior cruciate ligament and restructuring of peripheral part of medial or lateral sections of the bursal-ligamentous apparatus (it depends upon the nature of damage) by creation of active and passive derotators.

Biomechanical Phenomena↗
PubMedDate not supplied

A chiropractic perspective on atlantoaxial instability in Down's syndrome.

The purpose of this paper is to review the current information on atlantoaxial instability in Down's syndrome. There are potentially fatal consequences to performing adjustive manipulation to the cervical spine of the Down's patient. Atlantoaxial subluxation can cause death. Up to 50% of those suffering from atlantoaxial instability have it due to anomalous axis formation and/or agenesis or laxity of the transverse ligament. Trauma or progressive anterior displacement of atlas may cause serious neurological complications. The standard treatment for atlantoaxial instability is surgical fusion of the upper cervical spine. Conservative chiropractic care is suggested as a possible alternative in some cases. Standards for adjusting patients suffering from Down's syndrome have not been established. However, guidelines reviewed in this paper may indicate when adjusting may be hazardous. Potential protocol for the evaluation and diagnosis of atlantoaxial instability are suggested.

Atlanto-Axial Joint↗
PubMed1990

[Possibilities of computerized arthrotomography in the diagnosis of shoulder instabilities].

Shoulder instability can usually be diagnosed by examination of the history and a careful physical examination. Additional diagnostic studies include radiographic investigations and arthroscopy as a functional and very comprehensive diagnostic procedure for shoulder lesions. Conventional radiographic investigations with special projections have proven to be reliable in revealing bony changes of the glenoid and of the humeral head, whereas CT arthrography is very helpful in evaluating capsulolabral lesions associated with shoulder instability. This kind of investigation is a highly sensitive and less invasive technique. Combined with intraarticular application of contrast medium the extent of pathologic changes associated with instability can be imaged and differentiated from other intraarticular causes of dysfunction. During a 1-year period, 42 patients were studied by double contrast arthrography followed by CT examination, and 33 were found to have a shoulder instability. The intention of this report is to describe a few CT arthrographic findings in the presence of pathologic anatomy of unstable shoulders.

Adolescent↗
PubMed1990

[Clinical picture of anterior instability of the shoulder joint].

The authors have studied the clinical picture of 360 patients with primary traumatic dislocations and the long-term results have been observed in 286 patients. The analysis of 50 arthrotomies of the shoulder performed in cases of anterior instability has been made. A direct relationship between the clinical course of instability and the severity of the intra-articular lesions appearing during the first traumatic dislocation has been established. Such lesions include ruptures or avulsions of the anterior portion of the cartilage wall, ruptures of the joint capsule, avulsion of the capsule from the neck of the scapula, fractures of the anterior border of the glenoid cavity, compression fracture of the posterior lateral portion of the head of the humerus, etc, Inadequate treatment of traumatic dislocation leads to instability in the form of frequent dislocations or subluxations in the shoulder joint. The surgical treatment of the instability should be directed at the reconstruction of the injured structures of the shoulder joint.

Adult↗
PubMed1989

[The "positioned image" of the talo-calcaneus joint in instability of the posterior distal ankle joint].

With regard to the very common disease of sprained ankles the combined tear with ruptures of ligaments of the subtalar joint are possible. Even an isolated instability is known as the reason of long lasting post-traumatic complaints. Using the apparatus of Scheuba, well-known in diagnosing instabilities of the knee and ankle joint, a new standardized method controlling instabilities of the subtalar talo-calcanear joint is introduced. In an experimental investigation this radiological technique has been tested out in cadaveric ankle joints (nine joints) with artificial ligamentous lesions. The results show that in all cases an instability is recognizable radiologically using this technique. For clinical use the bilateral examination is recommended failing standardized values for unilateral use.

Humans↗
PubMed1989

[Radiology of patellar instability: contribution of the lateral radiography and the 30-degree axial view with external rotation].

Patellar instability is often missed by conventional axial views because transient subluxation of the patella essentially occurs during the first degrees of knee flexion (0 to 30 degrees), a position in which bilateral routine axial views are impossible to obtain. However, simple radiographic methods enable detection of both patellar instability and the often associated trochlear depth insufficiency. Every lateral radiograph of the knee depicts the depth of the proximal trochlear groove which is superior to 5 mm in a normal population. Upper trochlear depth insufficiency is frequently observed in the case of major patellar instability. Lateral views of the knee recorded during the first degrees of flexion (0 degrees-15 degrees) enable detection of patellar maltracking through the patellar tilt always associated with significant subluxation of the patella. Patellar maltracking may be studied dynamically by lateral fluoroscopy during progressive flexion of the knee. Unilateral 30 degrees axial radiographs with forced lateral rotation of the leg are definitely superior to conventional axial views in detecting transient patellar subluxation. These simple radiographic modalities should replace computed tomography in the search for patellar instability.

Humans↗
PubMed1989

Glenohumeral movements of the involuntary inferior and multidirectional instability.

The glenohumeral movements of the involuntary inferior and multidirectional instability were studied by means of cineradiography. Using the devised two parameters, i.e., the shoulder center edge and glenoid angles, the author compared the glenohumeral movements of the normal shoulder with the involuntary inferior and multidirectional instability of the shoulder. The glenohumeral movements of the involuntary inferior and multidirectional instability showed not only an excessive excursion and sliding motion but also a deterioration of the scapular abduction and external rotation, with the arm progressively abducted. These phenomena were especially remarkable at the maximum elevation of the arm. The roentgenogram of the overhead view of the shoulder joint indicates whether or not there is an involuntary inferior and multidirectional instability, and whether or not these parameters can be useful for diagnosis of shoulder lesions.

Adolescent↗
PubMed1985

Chronic atlanto-axial instability in Down syndrome.

We studied the radiographs of thirty-two patients with Down syndrome for evidence of atlanto-axial instability. One of the patients had instability in 1970 and seven had it in 1983. The interval between the atlas and the odontoid process in the patients who demonstrated motion at that interval radiographically averaged 2.78 millimeters in 1970 and 6.93 millimeters in 1983 (p less than 0.005). Four patients whose radiographs showed atlanto-axial motion in 1970 lost that motion by 1983, and in seven patients who did not show atlanto-axial instability in 1970 it developed by 1983. Atlanto-axial instability was more likely to develop in boys who were more than ten years old. Accessory upper-cervical ossicles became evident in three patients, none of whom had atlanto-axial motion. However, one of these three patients had an abnormally wide atlanto-axial interval.

Age Factors↗
PubMed1986

Instability of the patellofemoral joint in Down syndrome.

The knees of 210 institutionalized patients with Down syndrome were evaluated to determine the prevalence of patellofemoral instability and to assess the value of orthotic and surgical treatment. The cases of 151 non-institutionalized patients with Down syndrome were also reviewed. The patella was dislocatable or dislocated in thirty-five knees (8.3 per cent) in the institutionalized group and in twelve knees (4.0 per cent) in the non-institutionalized group. This interfered with walking in some patients, but only three of the patients were unable to walk because of patellofemoral instability. None of the institutionalized patients used any form of orthosis, and only three non-institutionalized patients used an orthosis. Eight knees in five patients had been operated on, and they had an average length of follow-up of 16.8 years. Four of these knees had a satisfactory result. Instability of the patellofemoral joint may occur in patients with Down syndrome but is rarely disabling. Almost all patients with patellofemoral instability adapted to the problem and were able to walk.

Adaptation, Physiological↗
PubMed1987

Atlantoaxial instability in individuals with Down syndrome: epidemiologic, radiographic, and clinical studies.

Atlantoaxial instability is a relatively frequent finding in individuals with Down syndrome. We examined 404 patients with this chromosome disorder and observed their atlanto-dens intervals and spinal canal widths to be significantly different from children without Down syndrome. Significant differences were also noted between boys and girls with Down syndrome in spinal canal widths but not in atlanto-dens interval measurements. When different neck positions were compared, measurements obtained in flexion were significantly greater than in extension or in neutral position. In addition, more patients had greater than or equal to 5 mm atlanto-dens interval measurements in flexion than in extension or neutral. A total of 59 (14.6%) of 404 patients displayed atlantoaxial instability. Fifty-three (13.1%) patients had asymptomatic atlantoaxial instability, and special precautions will have to be taken with this group of children. Six (1.5%) patients had symptomatic atlantoaxial instability who underwent surgery to prevent further injury to the spinal cord. In our follow-up studies of 95 patients with Down syndrome, we did not find any significant changes during either clinical or radiographic reexaminations.

Adolescent↗
PubMed1988

Atlantoaxial instability in individuals with Down syndrome: a fresh look at the evidence.

In 1984, the Committee on Sports Medicine of the American Academy of Pediatrics published in this journal a statement on the remarkably high incidence of atlantoaxial instability among individuals with Down syndrome. On the assumption that this instability, demonstrable through a specified series of lateral x-ray films of the neck, constituted a predisposition to cervical spine dislocation with subsequent spinal cord compression, the Academy supported and made more specific a series of recommendations that had originated from the Kennedy Foundation a year previously. In essence, for those persons who are found to have the radiographic sign of instability, participation in sports should be restricted. Because the implementation of these recommendations could deprive tens of thousands of individuals with Down syndrome of activities that are emotionally and physically beneficial and because of the rarity of reported cervical dislocations associated with injury, a case review was done. Included were those cases cited as support for the recommendations along with additional reports that had been omitted and a few cases reported subsequently. Little support for the hypothesis that atlantoaxial "instability" is a predisposing factor to "dislocation" was found, although much was found to indicate an urgent need for carefully designed longitudinal studies. Because nearly all of the cases of actual dislocation were preceded by at least several weeks of readily detectable physical signs, a physical examination with careful attention to neurologic signs prior to participation in sports is more predictive of potential or impending dislocation than the radiologic criteria currently recommended.

Atlanto-Axial Joint↗
PubMed1988

Patellar instability after total knee arthroplasty.

Twenty-five knees with symptomatic lateral patellar instability after total knee arthroplasty (TKA) were treated by operative realignment. Causes of instability include errors in surgical technique, quadriceps imbalance, and trauma. Fourteen knees had proximal realignment, nine had combined proximal and distal realignment, and two had component revision. At an average follow-up period of 50 months, 20 knees had normal patellar tracking and five had recurrent instability. Two patellar tendon ruptures occurred after combined realignment. Proximal realignment alone, in the absence of component malposition, is recommended for the management of patellar instability. Component malposition should be corrected by component revision. Combined proximal and distal realignment procedures are recommended only with great caution because of the predisposition to serious complications such as patellar tendon rupture.

Aged↗
PubMed1987

Evaluation and classification of shoulder instability. With special reference to examination under anesthesia.

Increasing knowledge of instability in the shoulder has created a more complex evaluation sequence. The history continues to be important. Many physical examination maneuvers are available to further define the problem. Routine roentgenographic examination has been extended to include views specifically designed to demonstrate subtle bony changes. Complex radiographic contrast studies, especially computed arthrotomography, can confirm most anatomic lesions. When surgical treatment is under consideration, reexamination under anesthesia is increasingly being recognized as an important, essential procedure. Arthroscopy will effectively identify pathologic lesions within the joint and confirm uncertain diagnoses. An organized sequence of examinations is necessary for a thorough clinical investigation. After the investigation is complete, a classification of the shoulder instability can be made that relates to the results of treatment. The classification includes the elements of etiology, volition, direction of instability, and degree of instability.

Anesthesia↗
PubMed1987

Update on the evaluation of instability of the lower cervical spine.

Clinical instability of the cervical spine should be diagnosed accurately in order to avoid both unnecessary treatment and the serious consequences of inadequate treatment. A systematic method for evaluation utilizing a checklist is suggested. The checklist is based on biomechanical analysis, anatomic analysis, experimental data and clinical studies. The elements of the checklist include (1) evaluation of anatomic components; (2) static radiographic measurements of sagittal plane displacements; (3) a dynamic (stretch test) evaluation of displacements; (4) evaluation of neurologic status; and (5) a consideration of future anticipated loads to the spine. Based on an analysis of these elements and an assignment of numerical values to each, the stability or instability of the spine can be determined. This systematic checklist approach is recommended as a useful method for evaluating clinical instability, given the currently available knowledge. This methodology and current knowledge about the complex problem of spinal instability have certain limitations. Progress will come with more biomechanical experimental studies and controlled prospective clinical studies.

Biomechanical Phenomena↗
PubMed1986

Clinical experience with double contrast medium computerised tomography (arthro-CT) in instability of the shoulder.

The authors discuss the value of computerised tomography combined with double contrast medium arthrography in the various pathological conditions associated with scapulohumeral instability. The results obtained in 18 patients with anterior instability and the findings reported in the literature indicate that arthro-C.T. is currently the simplest, most reliable and most comprehensive procedure for investigation of the lesions of the bones, joint capsule and glenoid labrum associated with instability of the shoulder. It is particularly indicated in the forms of instability in which there are no documented episodes of dislocation, while in cases of recurrent dislocation it provides a complete overview of the bone and capsule lesions that can be used as a basis for individually tailored surgical treatment.

Adult↗
PubMed1987

Occipito-atlantal instability in children. A report of five cases and review of the literature.

We are reporting the cases of five patients who had occipito-atlantal instability, a rare condition that may be due to either trauma or congenital abnormalities. In three of the patients the instability was secondary to trauma. The clinical and neurological manifestations were varied and included cardiorespiratory arrest, motor weakness, quadriplegia, torticollis, pain in the neck, vertigo, and projectile vomiting. All of the patients underwent posterior arthrodesis of the occiput to the first or second cervical vertebra. In the patients who had trauma-related instability, surgery was performed when immobilization in a cast failed to stabilize the spine; in the patients who had a congenital abnormality, arthrodesis was indicated because of persistent symptoms and the potential for catastrophe with minor trauma. Based on our experience, we recommend surgical stabilization by posterior arthrodesis when this form of instability of the cervical spine is diagnosed.

Adolescent↗
PubMed1985

Carbon fiber replacement of the ligaments of the shoulder girdle and the treatment of lateral instability of the ankle joint.

A normal active human being will not accept chronic instability or persistent luxation of any joint. Many attempts have been made to stabilize a damaged joint with autogeneic and allogeneic materials and by various surgical techniques. In animal and clinical trials, carbon fibers are reported to be a promising material for ligament replacement in chronic joint instability. The authors are investigating carbon fibers not only for repair of chronic instability of knee joints but also for chronic luxations and subluxations of the sternoclavicular, acromioclavicular, and ankle joints. For long-term stability of the new ligament, carbon fibers must be implanted in cancellous bone channels. Ingrowth of connective tissue and newly formed bone produces a secure ligament anchorage. A temporary tension band wire loop immobilizes the sternoclavicular or acromioclavicular joint. The ankle ligament replacements are immobilized with a weight-bearing plaster boot for six weeks postoperation. The use of carbon fibers as a ligament replacement in the sternoclavicular, acromioclavicular, and ankle joints produces favorable functions and stability. Reconstruction of the normal ligament insertions of a joint is essential, particularly with respect to supination and free range of movement. Of 56 cases with lateral chronic instability of the ankle, 51 with a mean average postoperative follow-up period of two years, 49 had subjectively good results. Stable joints were demonstrable in 48 cases; supination was limited in four cases.

Acromioclavicular Joint↗