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PubMed2006

Multiple myeloma of the cervical spine: treatment strategies for pain and spinal instability.

OBJECT: Metastases of multiple myeloma often occur in the cervical spine. These metastases may cause pain and associated spinal instability. The authors report the results of radiotherapy and surgical treatment for myeloma involving the cervical spine. The results of radiation therapy for multiple myeloma metastases to the cervical spine that cause clinical or radiographically documented instability have not been reported previously. METHODS: A retrospective chart review of patients with multiple myeloma metastases to the cervical spine was undertaken. Between 1993 and 2005, 35 patients were treated with external-beam radiation and/or surgical stabilization at the University of Texas M. D. Anderson Cancer Center in Houston, Texas. Nineteen of 20 patients with sufficient follow-up data experienced resolution of their pain when treated with radiation without surgical intervention. Twenty-three patients had evidence of spinal instability on radiographic images; 15 of these were treated with radiation alone. Of these, 10 had sufficient follow-up data, and none showed any clinical progression of instability. Radiographic follow-up images demonstrated an arrest of further progression of instability and, in some cases, healing of pathological fractures by means of radiation alone. CONCLUSIONS: The results of this series suggest that, in selected cases, external-beam radiation for multiple myeloma metastases to the cervical spine is an effective palliative treatment, even in cases involving clinical or radiographically documented instability.

Adult↗
PubMed1988

Anterior glenohumeral instability.

The understanding of and approach to anterior shoulder instability has changed and improved dramatically in recent years. It is now accepted that a shoulder can subluxate as well as dislocate and that chronic instability may or may not be caused by an initial traumatic event. An anteriorly unstable shoulder also can be unstable inferiorly and/or posteriorly (multi-directional instability). The author's diagnostic acumen has increased with the addition of glenohumeral axillary arthrotomography, glenohumeral CT arthrography, glenohumeral arthroscopy, and other studies. Surgical treatment has moved away from "repair of choice" to an "anatomic reconstruction." The current preferred treatment is to identify and repair only the pathology while preserving normal anatomy, hoping to restore shoulder stability, while preserving normal mobility and strength. Areas of controversy exist. 1) How long should acute dislocations be immobilized, if at all, and is physiotherapy helpful in preventing chronic instability? 2) How long should the surgically repaired shoulder be immobilized, if at all? 3) Is there a place for therapeutic arthroscopy in this area? Also controversial is the concept of "functional instability" or shoulder internal derangement. These patients are felt to have shoulder slipping and catching due to the intermittent interposition of a fragment of tissue (a torn labrum, a loose body, etc) between the articulating surfaces. Arthroscopic debridement of the pathology would be ideally suited for such a clinical entity. Undoubtedly, improvements and controversy will continue until orthopedists are able to accurately diagnose and correct shoulder instability, while preserving range of motion and strength at minimal inconvenience to the patient.

Humans↗
PubMed2006

Complex elbow instability.

Complex elbow instability consists of dislocation of the ulnohumeral joint with a concomitant fracture of one or several of the bony stabilizers of the elbow, including the radial head, proximal ulna, coronoid process, or distal humerus. Recurrent instability is not often associated with simple dislocation, but an improperly managed complex dislocation may be a prelude to chronic, recurrent elbow instability. Complex instability is significantly more demanding to manage than simple instability. Radial head, coronoid, and olecranon fracture associated with dislocation each must be assessed and often require surgery. Long-term outcome with surgical management of complex elbow injuries is unknown. A few published series examine combinations of different injury patterns managed with various methods. Recently, however, several well-designed prospective outcome studies have evaluated management of several different individual fracture-dislocation patterns with a unified treatment algorithm. Fixation or replacement of injured bony elements, ligamentous repair, and hinged fixation may be used to successfully manage complex elbow instability.

Collateral Ligaments↗
PubMedDate not supplied

Effects of foot orthoses on patients with chronic ankle instability.

Chronic instability of the ankle can be the result of mechanical and functional deficits. An acute ankle sprain can cause mechanical and functional instability, which may or may not respond to standard rehabilitation programs. Chronic instability results when there is persistent joint laxity of the ankle or when one or more components of neuromuscular control of the ankle are compromised. A loss of balance or postural control seems to be the most consistent finding among athletes with chronic instability of the ankle. Recent research in patients with acute and chronic ankle instability has revealed positive effects of foot orthoses on postural control. This article reviews the current research relevant to the use of foot orthoses in patients with chronic ankle instability and clarifies the suggested benefits and the shortcomings of these investigations.

Ankle Joint↗
PubMed1999

Elbow instability.

An understanding of elbow instability is predicated on knowledge of the anatomy of the lateral collateral ligament complex and of the mechanism and kinematics of elbow subluxation and dislocation. The lateral collateral ligament complex is the key structure involved in recurrent elbow instability and it is virtually always disrupted in elbow dislocations that result from a fall. The ulnar part of the lateral collateral ligament complex (also known as lateral ulnar collateral ligament) is the critical portion of the ligament complex securing the ulna to the humerus and preventing posterolateral rotatory instability. The kinematics of elbow subluxation and dislocation are a three dimensional coupled motion referred to as posterolateral rotatory instability in which the forearm rotates off the humerus in valgus/external rotation during flexion from the extended position. Elbow instability is diagnosed on clinical examination by the lateral pivot-shift test, the posterolateral rotatory apprehension and drawer tests and on radiographic examination by performing stress x-rays. While the lateral pivot-shift test is difficult to perform, the posterolateral rotatory drawer test is much less difficult. The most sensitive test, however, is the posterolateral rotatory apprehension test. A positive apprehension test in a patient presenting with a history of recurrent painful clicking, snapping, clucking, or locking of the elbow should lead one directly to the suspected diagnosis of posterolateral rotatory instability. Treatment is surgical, by repair or reconstruction of the lateral collateral ligament complex, specifically the ulnar part. Deficiencies of the coronoid and/or radial head must be addressed.

Collateral Ligaments↗
PubMed2002

Injuries to the posterior cruciate ligament and posterolateral instabilities of the knee.

Unlike anterior cruciate ligament (ACL) injury, disability from isolated posterior cruciate ligament (PCL) injury varies from no interference with life style to severe impairment of daily activities. Therefore, management of isolated PCL injuries remains controversial. High-energy vehicular accidents often cause more-serious PCL injuries, while less-severe injuries result from low-energy trauma including sports. The natural history and prognosis of PCL injury are correlated with the type and extent of instability and the development of degenerative changes in the knee. Indications for surgery include pain and instability of the knee. Arthroscopic single-bundle PCL reconstruction improved the function and stability of the knee with 77.4% satisfactory results in medium-term follow-up. Complete restoration of ligament stability was achieved in only 52% of knees, while 1/3 of the knees showed mild and 9.7% showed moderate residual ligament laxity. The incidence of degenerative changes was 52%, and the rate was correlated with duration of injury and severity of ligament laxity. Therefore, the significance of PCL injury has been overly simplified, and the functional disability of knees with PCL injury underestimated. Early surgical reconstruction of knees with grade III PCL injury is recommended. PCL injury is frequently associated with multiple ligamentous injuries. Combined PCL and posterolateral instabilities are serious knee injuries and frequently result in severe functional disability due to pain, instability, and degenerative changes in the knee. Unlike isolated PCL injury, there is a consensus of opinion that surgical reconstruction is indicated in knees with combined PCL and posterolateral instabilities. Commonly employed methods of reconstruction of the posterolateral corner include popliteus reconstruction, lateral collateral reconstruction or advancement, and a combination of the two. Combined arthroscopic PCL reconstruction and posterolateral reconstruction achieved 64% satisfactory (24% excellent and 40% good) and 36% unsatisfactory (24% fair and 12% poor) results over an average of 32 months of follow-up. Complete restoration of ligament stability was noted in only 44% of knees. The incidence of degenerative changes was 44%, and the rate was correlated with duration from injury to surgery and severity of ligament laxity. Despite the fact that currently employed surgical techniques only achieve modest success in restoration of ligament stability, early surgical reconstruction in knees with combined PCL and posterolateral instabilities achieved the best clinical results and a high rate of patient satisfaction.

Biomechanical Phenomena↗
PubMed2003

Flexion instability in primary total knee replacement.

Although the results of TKR are highly successful at long-term follow-up, failures occur. One of the more frequent causes of failure is instability. In distinction to instability in the medial-lateral plane, AP instability in flexion has been poorly described until recently. Although acquired ligamentous incompetence can occur, particularly with cruciate retaining prostheses, many cases of flexion instability result from an intraoperative failure to create symmetric balanced flexion and extension spaces. In primary TKR, use of a well-designed posterior stabilized prosthesis and creation of symmetric balanced flexion and extension gaps should minimize the incidence of postoperative flexion instability. If flexion instability occurs, the role of nonoperative treatment is limited. In most cases, revision TKR using the same basic principles is required. When symmetric flexion and extension spaces cannot be produced intraoperatively in complex primary or revision surgery, use of a more constrained articulation, such as a constrained condylar prosthesis or hinged prosthesis, is required.

Arthroplasty, Replacement, Knee↗
PubMed1992

[Instability and misdiagnosed or neglected dislocations of the upper cervical spine in children. Apropos of 20 cases].

Neglected instabilities or luxations of the upper cervical spine in children are rare if one discards conditions such as chondrodysplasia, Down Syndrome or others, were the spine is known to be at high risk of instability. We have studied twenty cases of neglected luxations and the delay in diagnosis is explained either by the asymptomatic character of some of these lesions, or by the difficulty in diagnosis. At the occipito-atlantal level we have reviewed: an instability in translation which required an occipito-axial fusion; two compensatory counter occipito-atlantal luxation of an atlanto-axial rotatory fixation. The diagnosis was best made with computed tomography scan and the treatment was not much different from the isolated atlanto-axial rotatory luxation. An instability in flexion extension, which was merely followed at regular intervals. At the atlanto-axial level 9 cases of sagittal instabilities in kyphosis and translation with a distance between atlas and axis of more than 5 mm were observed. These instabilities were most often associated with a malformation of the cranio-cervical junction; their treatment was usually surgical by means of an atlanto-axial or occipito-axial arthrodesis depending on the case. 9 other cases of atlanto-axial rotatory luxations were either isolated (7 cases) or associated with a counter occipito-atlantal rotatory subluxation (2 cases). Their diagnosis was made on routine X-rays, but the complete or incomplete aspect of the luxation, as well as its fixed aspect, was best appreciated with dynamic CT scan. Their treatment was always started with collar neck or halo traction in order to obtain, reduction of the dislocation, or at least the disparition of the torticollis and the head straight up on shoulders. The stability of the spine was achieved with a minerva cast jacket, halo cast or spine fusion depending on the case.

Adolescent↗
PubMed1992

Occipital-cervical instability.

A retrospective clinicoroentgenographic study was done on 26 patients with atlantoaxial instability, 17 traumatic and nine nontraumatic. All were treated by means of surgical C1-C2 and occipital-C2 stabilization. The traumatic instability was associated with lesions of the odontoid process and the atlas transverse ligament. Instability may be endogenous or associated with fracture of the atlas. Surgical indication was determined by the level of the fracture line, neurologic symptoms, age, and presence of multiple lesions. C1-C2 stabilization by means of wiring and iliac graft was the selected treatment. Fusion between the occipital and C2 segment was indicated in case of irreducible dens pseudoarthrosis. Fracture on the os odontoideum was very unstable and required greater C1-C2 fusion. Nontraumatic C1-C2 instability was either congenital or secondary to pathologic fractures. Rheumatoid arthritis, which produces anterior displacement of the atlas over the dens to more than 10 mm, neurologic symptoms, or untreatable pain must be stabilized by means of C1-C2 fusion. When elevation of the dens or irreducible displacement of the atlas exists, the results were relatively poor. Tumorous instability produced pathologic fracture of the body of the axis and had to be treated with C1-C2 wiring on bone cement. Down's syndrome instability required occipitoaxial fusion and strict postoperative immobilization.

Adolescent↗
PubMed1991

[Sonographic versus radiological assessment of chronic outer ligament instability of the upper ankle joint].

Chronic instability of the lateral upper ankle joint ligament is usually diagnosed by clinical and radiological examination. For the evaluation of an ultrasound method of testing lateral instability of the ankle joint we carried out a prospective study. We examined 23 adults who were actively engaged in some form of sport (21 male, 2 female, mean age 32 years) and had a preexisting lateral instability of the ankle. The instability was measured in the standard planes using Scheuba's stress apparatus with simultaneous ultrasound monitoring. The ultrasound examination was performed by positioning the 5-MHz applicator on the lateral side of the Achilles tendon, thus defining a plane from which the instability could be measured in both examination planes by observing the deviation between dorsal inferior edge of the tibia and the dorsal border of the talar roll. For the two examination planes, Spearman's rank-correlation coefficient between the radiological and ultrasound methods was 0.83 and 0.92. The sensitivity of the ultrasound method was 0.90, and the specificity was 0.85. Our study showed a good correlation between the two methods. A pathological talar tilt according to radiological criteria was also revealed by ultrasonography. Thus, all the advantages of ultrasound are now available for the evaluation of chronic lateral instability of the ankle joint.

Adult↗
PubMed1991

[Surgical treatment of anterior shoulder instability].

Long-term results obtained with the procedures hitherto regarded as standard and new findings about the etiopathogenesis and biomechanics of shoulder instability allow the conclusion that there is no single technique that is suitable for all forms of instability. Rather, an optimal surgical treatment should be selected with regard to the particular pathologic anatomy. For the majority of anterior instabilities--most of which are traumatic in origin--lasting reattachment of the capsule ligamentous structures to the lower anterior glenoid rim without a change in the original anatomical conditions is indicated. This concept, first described by Perthes and made known by the publications of Bankart, has been incorporated into several operative procedures and has been subjected to various modifications and technical innovations, including adaptation for arthroscopic methods. In a small number of instabilities deformations of the bones articulating on each other in the joint are found. These should be compensated if they affect the biomechanics. Most instances of shoulder instability caused by constitutionally determined laxity of the capsule should be treated conservatively. Not until such measures have failed should an operation be carried out; depending on the extent and directions of the usually multi directional instability, different methods of tightening and strengthening of the capsule are required.

Biomechanical Phenomena↗
PubMed1991

[Possibilities of diagnostic sonography in assessment of instability of the shoulder joint].

In a prospective study we evaluated diagnostic ultrasound investigation for shoulder instabilities. We measured the passive antero-posterior translation in 150 healthy persons in relation to the dorsal glenoid as well as the inferior subluxation in relation to the acromion. After establishing these normative data, we examined 23 patients with anterior unidirectional instabilities and 34 with multidirectional instabilities by ultrasound. Our results showed that the dorsal humeral head circumference of a normal joint is located about 8 to 10 mm dorsally to the glenoid. In the control group with non-injured shoulder is significantly higher as in the nondominant shoulder (p less than 0.01). Patients with anterior instabilities showed a highly significant increase of anterior translation in the injured shoulder (p less than 0.0001). In comparison with the control group there is a highly significant increase of downward subluxation under load in patients with multidirectional instabilities (p less than 0.001). In patients with multidirectional instabilities, there is also a significant increase of spontaneous downward subluxation of the dominant shoulder (p less than 0.01). In habitual or voluntary dislocations the relation of the humeral head to the glenoid can be judged staticly and dynamically. Secondary signs of dislocation (Hill-Sachs lesions, joint effusion) are evident. 13 patients of a total number of 22 patients we operated on, had bony or cartilaginous Hill-Sachs lesion. The specificity of preoperative ultrasound in detecting these Hill-Sachs lesions was 100% and the sensitivity was 89%.

Adolescent↗
PubMed1988

Tendon transfer for lateral ankle and subtalar joint instability.

Seventy-three patients suffering from lateral instability of the ankle joint, bilateral in 6 cases and combined with subtalar instability in 25, were operated on using the distal part of the peroneus brevis tendon. The tendon was pulled through two bore canals in the lateral malleolus and fixed in a bore hole in the calcaneus. The direction of the tendon in relation to the calcaneus and the talus was varied depending upon the type of instability. At 9 and 24 months follow-up, all but 2 patients had substantial reduction of the radiographically measured instability. No subtalar instability could be disclosed, and all the patients could return to normal levels of activity. The operation can be recommended for chronic lateral ankle and subtalar joint instability.

Adolescent↗
PubMed1988

[Development and forms of post-traumatic carpal instability].

Posttraumatic carpal instabilities may be caused either by fractures or by rupture of the ligaments and originate mostly from a sudden fall on the hand risen in defense. In this case forced dorsiflexion, supination and ulnarduction will be developed in the wrist joint and intracarpal region. The injury takes its course in four stages. According to the localisation we differ between radial carpal instabilities, which develop especially in the stages I and II, ulnar instabilities, which develop in the stages III and IV. Furthermore there exists a third kind of instability: the proximal carpal instability, which is localised in the radiocarpal joint. In addition to that we differ static and dynamic instabilities. For treatment in recent injuries the continuity of the ligaments and the shape and the size of the carpal bones are restored. In delayed cases it will be necessary to restore the ligaments by grafting, to perform intracarpal arthrodesis or osteotomy to correct the bony configuration.

Carpal Bones↗
PubMed1987

[Personal experiences in surgical treatment of chronic instability of the anterior knee joint].

The results achieved with three different operative methods for the treatment of chronic anterior instabilities of the knee joint are presented. In 23 patients Trillat's modification of the O'Donoghue procedure was performed to reconstruct the medial collateral ligaments and the posterior capsule. Thirteen patients underwent reconstruction of the cruciate ligament with a free graft of the patellar ligament according to the Brückner method. In 37 patients the Brückner method was used for cruciate ligament replacement combined with lateral repair according to Ellison, and in some of these patients the posteromedial portion of the capsule was also reconstructed. Seventy-three patients (87.9% of all operated cases) were followed-up. The average observation period was 2.9 years and the mean age at the time of operation was 33.1 years. Major meniscal lesions were noted in 42 patients (57.5% of the cases). Twenty patients presented with combined instabilities or anteromedial grade II instabilities preoperatively. The majority of cases (53 patients) exhibited complex instabilities or anteromedial grade III instabilities preoperatively. At follow-up the Lachmann test was negative or trace-positive in 11 patients (48%) of group I, in 9 patients (69%) of group II, and in 34 patients (92%) of group III. Other stability tests, such as the pivot shift test and the drawer test, confirmed the superiority of group III. The overall results--considering both objective and subjective factors--showed good to excellent results in 12 patients of group I (52%), in 8 patients of group II (62%), and in 31 patients of group III (84%). We therefore conclude that combined and complex instabilities are indications for surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

Physical examination in the diagnosis of rotatory instability.

Various tests are used to evaluate rotatory instability. Anteromedial rotatory instability (AMRI) is detected by performing an anterior drawer test with the foot in external rotation. Excessive anterior rotation of the medial tibial plateau indicates laxity of the medial structures. Anterolateral rotatory instability (ALRI) is a manifestation of an anterior cruciate ligament (ACL) deficient knee. The functional disability produced is the pivot shift phenomenon, which is elicited by the MacIntosh, jerk, ALRI, FRD, and Losee tests. Posteromedial rotatory instability is checked by noting a posteromedial displacement of the medial tibial plateau with a valgus stress. This is a relatively unusual type of instability, although it may be part of a severe valgus type. Posterolateral rotatory instability is evaluated by the external rotation recurvatum, posterolateral drawer, and reverse pivot shift tests. The abnormalities produced by these tests will clarify the method to correct the functional deficiency.

Humans↗
PubMed1998

[Significance of computerized tomography in the diagnosis of post-traumatic proximal carpal instability].

INTRODUCTION: Proximal carpal instability is a painful condition characterized by early or late loss of radioulnar joint (RUJ) congruence not affecting the normal bone alignment of the two carpal rows. The joint incongruence or (incomplete) dislocation which leads to proximal instability is caused by many traumatic and nontraumatic events. The diagnosis of (incomplete) dislocation of the distal RUJ may be extremely difficult to make at conventional radiography because such injuries can be seen only when the lateral joint projection is perfect; otherwise the diagnosis is not reliable. CT is the only imaging tool diagnosing the grade of distal RUJ congruence independent of the examination technique. MATERIAL AND METHODS: We studied the radiocarpal complex conditions leading to proximal instability at the Rizzoli Orthopedic Institute from December, 1995, through December, 1997. In all, 389 cases were seen, 376 from trauma and 13 of nontraumatic origin. Each injury was studied with conventional radiography, CT, and MRI. Radiography was performed in two projections, namely the posteroanterior one with hand extension and the lateral one with the forearm in neutral position and the elbow bent at 90 degrees; the projections were repeated whenever a cast brace was applied. Unenhanced CT was performed for comparison with the patient prone and the forearm and wrist in prone and neutral position, as well as with the patient, forearm and wrist supine. Three criteria of electronic image processing were adopted for the RUJ studies in the 3 projections: radioulnar lines, congruence, and epicenter. MRI was always performed after conventional radiography and CT. Only the involved radiocarpal region was studied; coronal, axial and sagittal images were acquired with T2-weighted GE and T1-weighted SE sequences. RESULTS: Proximal instability was found in 17 of 389 patients; it was early in 13 and late in 4 of them. The comparison of radiographic and CT results showed that the former method is unreliable, with 53% false negatives. Pain, a cast brace, congenital or acquired deformities of distal radius and ulna and patient mispositioning by the radiology technician can change the rotation of the forearm, wrist and hand and make a perfect laterolateral projection in neutral position unfeasible, which affects the radiographic diagnosis. Conversely, CT showed its extreme efficacy in assessing the distal RUJ congruence with no false negatives independent of the RUJ rotation and of instability type and grade. CONCLUSIONS: Conventional radiography is a poorly reliable tool for the diagnosis of joint incongruence and its grade. In contrast, CT can diagnose a RUJ (incomplete) dislocation easily and unquestionably, thanks to its axial capabilities, even when adequate radiographic studies would be unfeasible. If the anteroposterior projection of the radiocarpal complex shows a congenital or acquired deformity of distal radius, the lateral projection can be skipped and a CT scan in prone, neutral and supine position performed. The 3 CT criteria quantify incongruence type and grade, and also demonstrate the position of maximum incongruence and its decrease by position. The comparative study of the radiocarpal region makes CT a very useful and valuable tool in congenital instability because its allows the assessment of contralateral radioulnar congruence too. MRI is very useful in the diagnosis of injury or degeneration of the fibrocartilage complex, namely in patients with no bone changes at conventional radiography.

Humans↗
PubMed2026

A system-level metastable model of cancer evolution: integrating replication stress, cell cycle deregulation and chromosomal instability.

INTRODUCTION: Cancer cell proliferation occurs within the context of persistent genomic instability. In this review, we propose the RS-CCD-CIN axis as a systems-level framework in which replication stress (RS), cell cycle deregulation (CCD) and chromosomal instability (CIN) form an interdependent triad that shapes tumour evolution. This axis represents a constrained metastable state in which genomic instability is tolerated and buffered. The objective of this review is to synthesize the current understanding of how the RS-CCD-CIN axis contributes to tumour heterogeneity, adaptability and therapy response. DISCUSSION: Evidence indicates that RS, CCD and CIN operate as a dynamic, interconnected network rather than as independent processes. Replication stress induces DNA damage and mutagenesis, while partial checkpoint disruption permits cells with unresolved lesions to proliferate. Chromosomal instability generates both structural and numerical alterations, contributing to intratumoural heterogeneity. Together, these processes facilitate adaptation to environmental and therapeutic pressures. Extrachromosomal DNA, micronuclei formation and cytosolic DNA signalling, including the cGAS-STING pathway, connect genomic instability to adaptive responses and immune modulation. Single-cell and spatial profiling reveal temporal and spatial variability in RS, CCD and CIN states, highlighting the limitations of static biomarkers. Therapeutically, targeting individual components often yields limited durability, whereas approaches that simultaneously perturb multiple aspects of the RS-CCD-CIN axis may improve clinical outcomes. CONCLUSIONS: This review highlights the RS-CCD-CIN axis as a fragile and metastable architecture that supports cancer evolution, while also being susceptible to collapse. A deeper understanding of this interconnected framework may inform the development of therapeutic strategies and enhance the management of resistance.

Humans↗