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At least 973 records · Page 54Linked to original sources
PubMed2002

Bankart repair in traumatic anterior shoulder instability: open versus arthroscopic technique.

PURPOSE: The purpose of this study was to compare the results of open and arthroscopic Bankart repair using suture anchors in traumatic anterior glenohumeral instability. Variables measured were recurrence rate, range of motion, and return to preinjury activity. TYPE OF STUDY: Case control study. METHODS: Eighty-nine shoulders in 88 patients with traumatic unilateral anterior shoulder instability were evaluated using Rowe and University of California Los Angeles scores, recurrence, return to activity, and range of motion by an independent examiner at an average of 39 months after either an arthroscopic or open Bankart repair using suture anchors. The arthroscopic technique included a minimum of 3 anchors in most patients and a routine incorporation of capsular plication and proximal shift. Of the 89 shoulders, 30 shoulders (30 patients) underwent open Bankart repair and 59 shoulders (58 patients) underwent arthroscopic Bankart repair. RESULTS: Twenty-six shoulders (86.6%) in the open repair group showed excellent or good results, and 54 (91.5%) shoulders in the arthroscopic repair group showed excellent or good results. The arthroscopic group revealed slightly higher scores in the Rowe (P =.041) and UCLA scores (P =.026). Two patients (6.7%) in the open repair group and 2 (3.4%) in the arthroscopic repair group had experienced at least 1 episode of redislocation after the surgery. One patient (3.3%) in the open repair group and 4 (6.8%) in the arthroscopic repair group demonstrated mild apprehension. The overall residual instability was 10% in the open repair group and 10.2% in the arthroscopic repair group. There were no significant differences in the loss of external rotation and return to prior activity between the 2 groups (P >.05). Residual instability occurred more frequently in patients with fewer anchors. CONCLUSIONS: Arthroscopic suture anchor capsulorraphy showed similar results to the open Bankart procedure.

Adolescent↗
PubMed2000

Peripheral tears of the triangular fibrocartilage complex cause distal radioulnar joint instability after distal radial fractures.

The aim of this prospective study was to determine whether peripheral tears of the triangular fibrocartilage complex (TFCC) in patients younger than the osteoporotic age (males,<60 years; females, <50 years) were related to chronic distal radioulnar joint (DRUJ) instability. Fifty-one patients (27 women) with displaced distal radial fractures were included in the study. The median age was 41 years (range, 20-57 years). Arthroscopy at the time of fracture showed complete or partial TFCC tears in 43 patients (24 had only peripheral tears, 10 had only central perforations, and 9 had combined tears). The 1-year (range, 11-27 months) follow-up period included an interview, physical examination, and radiographic evaluation. Ten of the 11 patients with complete peripheral TFCC tears had DRUJ instability at the follow-up examination compared with 7 of the 32 patients with only partial or no peripheral tears. Patients with instability of the DRUJ had a worse Gartland and Werley wrist score. Instability was not associated with any radiographic finding either at the time of fracture or at the follow-up examination. Initial fracture or nonunion of the styloid was even slightly more common in stable patients.

Adult↗
PubMed1999

[Post-traumatic palmar instability of the thumb metacarpophalangeal joint. The "other skier's thumb"].

"Passive" and "active" stabilizers give the thumb metacarpophalangeal (MP) joint the necessary palmar stability. It is possible to temporarily stabilize the joint by means of the flexor muscles in cases where there is an injury to the palmar ligaments due to hyperextension trauma. However, sudden severe or prolonged strain may lead to palmar instability and/or stress-related pain. In an experimental study, the MP joints of 40 specimen thumbs were hyperextended to varying degrees. The extent of tissue damage was evaluated during dissection. Between 1984 and 1992, in 72 cases with acute hyperextension injury of the thumb MP joint, we X-rayed the thumb under stress during primary examination. Habitual instability was excluded by comparing X-ray films under stress of the opposite uninjured thumb. The treatment of the lesion depends on the degree of instability documented by the X-ray films. Experimentally, we found only partial lesions or ruptures with only slight dislocation of the ligament ends in cases where the MP joint was hyperextended up to 30 degrees. In cases with hyperextension of 60 degrees or more, there was usually a complete rupture of the ligaments or a fracture of the sesamoid bones with dislocation of the ligament ends as well as partial rupture of the thenar muscles. This injury pattern was also observed in clinical cases during surgery. Partial lesions of the palmar ligaments of the thumb MP joint can be treated conservatively with good results. In cases of complete palmar instability due to trauma, we saw better results after surgical reconstruction of the ligaments particularly in manual workers.

Athletic Injuries↗
PubMed2002

Functional instability of the ankle: differences in patterns of ankle and knee movement prior to and post landing in a single leg jump.

The aim of this study was to investigate motor control in subjects with functional instability of the ankle joint. This was achieved by analysing patterns of lower extremity motion prior to and immediately following landing during single leg jumping in subjects with functional instability of the ankle. Fourteen subjects with unilateral functional instability and 10 healthy control subjects performed single leg jumps from a 40 cm height whilst angular displacement of their ankle and knee joints were recorded. Subjects with functional instability demonstrated significantly greater ankle dorsiflexion over the period encompassing 10 ms pre landing to 20 ms post landing (p < 0.05). They also exhibited a significantly greater level of knee flexion than controls over the period from 20 ms pre landing to 60 ms post landing (p < 0.05). The timing of these significant differences leads us to conclude that they do not arise as a result of reflexively mediated peripheral events following landing.

Adolescent↗
PubMed2005

[Therapy for static scapholunate instability -- reconstruction of the dorsal part of the scapholunate ligament with a periosteal flap of the iliac crest].

Recurrent instability is frequent following capsulodesis, tenodesis, or ligament reconstruction in static scapholunate instability. Therefore a periosteal flap of the iliac crest was designed to reconstruct the dorsal part of the SL ligament, which is known to be the biomechanically strongest portion and also the axis of rotation between the scaphoid and lunate. Biomechanical testing of ten fresh frozen dorsal SL ligaments and ten periosteal flaps of the iliac crest showed similar properties concerning failure force, failure displacement, failure stress, energy to failure and stiffness. Results of eight specimens in each group were available following successful testing. Failure force of the dorsal SL ligament was 171.8 N (SD 44.2), energy to failure amounted 269.1 N-mm (SD 98.9), failure stress was 10.3 N/mm (2) (SD 1.3), failure displacement 2.9 mm (SD 0.4), and stiffness 77.2 N/mm (SD 21.4). Testing of the periosteal flap gave the following values: failure force 144.3 N (SD 38.7), energy to failure 217.9 N-mm (SD 85.0), failure stress 9.9 N/mm (2) (SD 1.7), failure displacement 3.0 mm (SD 0.4) and stiffness 60.5 N/mm (SD 14.7). In addition to these test values, clinical and radiological data of eleven patients were available following reconstruction of the dorsal SL ligament with a periosteal flap of the iliac crest. The interval between trauma and surgery was 15 months, mean follow-up was 29 months. One patient was free of pain, whereas ten mentioned pain during or following strenuous work. Two patients were completely satisfied, nine complained about some restriction during special activities. Active range of motion amounted to 56 degrees extension, 46 degrees flexion, 17 degrees radial abduction, 30 degrees ulnar abduction. Grip strength was 38.5 kg, which was 79 % of the contralateral side. Radiological evaluation demonstrated a correction of the static instability in nine cases. In two patients recurrence of static instability was obvious. The prerequisite for success of the procedure is the easy reduction of the carpals. In cases of a fixed rotatory subluxation of the scaphoid, the technique cannot maintain the reduction.

Adult↗
PubMed1998

[Changes in proprioceptive capacities of the shoulder joint in ventral shoulder instability. A comparative study before and after arthroscopic labrum refixation].

Measurements of movement sense determined by threshold levels for the perception of motion of the shoulder were performed in 10 patients with unilateral posttraumatic shoulder instabilities, in 30 patients who underwent arthroscopic labrum repair for recurrent anterior shoulder instability, and in 15 age-related controls. In patients with anterior shoulder instabilities threshold levels for the perception of motion were higher. In addition, movement sense measurements revealed a marked, but time dependent improve of proprioceptive abilities in patients who underwent arthroscopic labrum repair. While in the shoulders of patients with an postoperative period shorter than 18 months elevated threshold levels for the perception of motion still could be observed, after a postoperative period of 18 moths or more movement sense was not different from normal, uninjured shoulders. In conclusion, our study gives evidence for a proprioceptive deficit with anterior shoulder instability which improves significantly after arthroscopic labrum repair. The restitution of proprioceptive abilities, however, seems to be a time dependent process.

Adult↗
PubMed1995

[Double-contrast arthro-CT in diagnosis of shoulder instability].

Timeless and lesion-related treatment are important in the different shoulder instabilities in order to get a good functional result. Within the step-by-step programme of diagnostic possibilities the double contrast computerised arthrotomography is particularly indicated in recurrent posttraumatic and habitual dislocations, in subluxations as well as for clarification of causes of postoperative recurrence. Besides the documentation of skeletal changes (Hill-Sachs-lesion, Bankart defect), double-contrast arthro-CT offers the possibility to identify detachments of the joint capsule or labral tears. Between 11/90 and 9/93 we performed 38 double contrast arthro-CTs for recurrent shoulder instabilities. 35 men and 3 women were examined. The mean age of the sportive patients were 29 years. Preoperatively we diagnosed in 21 cases a recurrent posttraumatic, in 7 cases a habitual shoulder instability. Apart from one multidirectional and three posterior instabilities we found two cases of subluxation. In the meantime 24 patients were treated with an open stabilising operation of the shoulder. The operative findings were compared with the results of double contrast arthro-CT. In a total of 38 performed arthro-CTs we found labral tears in 4 cases, 14 labral dissections, and 10 times a complete labral discontinuity. 8 of 9 labrum dissections found intraoperatively were correctly identified on CT. One dissection was not even seen retrospectively on arthro-CT. Six of nine complete labrum discontinuities were seen on arthro-CT, three described as a dissection. All capsular detachments and bony Bankart lesions found on CT were confirmed intraoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Stabilometry recordings in functional and mechanical instability of the ankle joint.

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.

Ankle Joint↗
PubMedDate not supplied

[Arthroscopic trans-glenoid stabilization of post-traumatic anterior shoulder instability].

PURPOSE: Aim of this study was to evaluate the results after athroscopic transglenoidal stabilization in patients with anterior posttraumatic shoulder instability. METHODS: 30 patients with posttraumatic anterior shoulder instability were prospectively observed for a mean of 36 months (24-56) after an athroscopic stabilization has been performed. The operative technique was carried out as described by Morgan with use of transglenoidal sutures to repair the labrum. RESULTS: All patients had a Bankart lesion and a Hill-Sachs defect. According to the criteria of Rowe, 24 patients (80%) had good or excellent results and 1 patient (3%) was graded as fair. 5 patients (17%) developed recurrent instability 6-24 months postoperatively so they had failed results. 83.4% had no or little limitation in sports activity. Sex, age or grade of activity had no influence on the result concerning stability. The mean preoperative dislocation rate was 8.6 for the failures and 5.9 for the stable results (p < 0.05). CLINICAL RELEVANCE: The results of arthroscopic stabilization of the shoulder are inferior to the classical open repair. It should only be performed in patients with unidirectional, posttraumatic anterior shoulder instability without capsulaligamentous hyperlaxity or multiple resdislocations.

Adolescent↗
PubMedDate not supplied

[Neuroradiographic diagnosis of degenerative disk diseases--the Dusseldorf Diagnostic Disk program. III. Reproduction of pain and instability].

The goal of this study was to examine the relationship between pain reproduction test and instability in order to point out the clinical significance of radiological instability. The pain reproduction test was correlated with segmental instability of 103 patients and with traction spurs of 172 patients. There was no statistical correlation with the mentioned parameter. Therefore instability is considered only as a morphological parameter but it has no clinical importance.

Adult↗
PubMedDate not supplied

[Proprioceptive abilities of patients with post-traumatic instability of the glenohumeral joint].

PURPOSE: The purpose of this study was to evaluate joint position sense (JPS) in patients with posttraumatic glenohumeral instability. MATERIALS AND METHODS: In 28 patients with posttraumatic instability and in a matched control group of 30 subjects proprioception capability was evaluated. For documentation of proprioception an angle reproduction test (ART) was performed with which joint positions sense (JPS) was measured for abduction, flexion, and rotation in three angles each. RESULTS: In both groups there was a significant better JPS with visual control than without. In contrast to the control group the patients were not able to increase angle reproduction capability without visual control when comparing positions below shoulder level with positions at or above shoulder level. When comparing the patients to the controls there were differences in most of the ARTs with worse results in the patient group. These differences were significant in 150 degrees flexion with and without visual control, in 150 degrees abduction without and in 100 degrees abduction with visual control. For rotation there were trends for almost all joint positions, however, the differences were significant only in the -45 position. When comparing the noninjured contralateral shoulder of the patients with the control group, there still were differences. Again these were not in all joint positions significant, but significant worse JPS could be demonstrated in 150 degrees abduction without visual control, 50 degrees flexion without visual control, -45 degrees rotation without and 0 degrees rotation with visual control. CONCLUSIONS: A proprioceptive deficit can be documented in patients with posttraumatic glenohumeral instability. This may be one reason for permanent instability. The contralateral joint also shows reduction in joint position sense. For consecutive treatment as well as for rehabilitation both shoulder joint should be addressed.

Adult↗
PubMedDate not supplied

Translation of the glenohumeral joint in patients with multidirectional and posterior instability: awake examination versus examination under anesthesia.

The purpose of this study was to assist in establishing guidelines to determine the degree of shoulder instability, the value of awake clinical examination, and the value of examination under anesthesia (EUA). Forty-three patients with clinical diagnosis of multidirectional shoulder instability (MDI) and 28 patients with posterior instability underwent bilateral shoulder translation testing, both awake and while under anesthesia. Two surgeons using guidelines and translation grades developed by the American Shoulder and Elbow Surgeons examined each patient and assigned a single grade for the anterior, posterior, and inferior directions. A comparison of translational grade was performed with the use of Pearson chi2 and McNemar symmetry to determine association. The patients with MDI showed increased translation in the anterior, inferior, and posterior directions when the affected limb was compared with the noninvolved side in both preoperative examination and EUA. Furthermore, the patients with MDI showed increased anterior translation on the affected side during EUA compared with the clinical examination. Patients with posterior instability demonstrated increased anterior translation for both affected and noninvolved limbs during EUA. However, the posterior translation obtained before surgery did not change during EUA for both the affected and noninvolved limbs, and there was no side-to-side difference in posterior translation.

Adolescent↗
PubMedDate not supplied

The use of thermal capsulorrhaphy in the treatment of multidirectional instability.

The purpose of this study is to report on our experience with thermal capsulorrhaphy in the treatment of multidirectional instability of the shoulder. Thirty-three consecutive patients (33 shoulders) with multidirectional instability were treated with arthroscopic thermal capsulorrhaphy. Twelve patients had a history of traumatic dislocation. Three patients had been previously treated with open inferior capsular shift procedures. At a mean follow-up of 36 months (range, 24-40 months), results were available for 30 patients. On the basis of the UCLA rating scale, out of a possible 35 points, the mean preoperative score was 16.7 points and postoperatively it was 30.1 points, with 3 excellent, 20 good, and 7 poor results. Twenty-three patients (76%) were returned to full activity. In our experience the majority of patients with multidirectional instability were able to return to their previous occupations in the armed forces following thermal capsulorrhaphy. More information further defining the biomechanical pathology of capsular laxity and the specific role of electrothermal shrinkage in treating shoulder instability is needed.

Adult↗
PubMedDate not supplied

Inferior capsular shift for multidirectional instability following failed laser-assisted capsular shrinkage.

This report is a prospective study of 10 consecutive patients treated by open inferior capsular shift following failed laser-assisted capsular shrinkage. Six patients had true multidirectional instability, 2 had anteroinferior instability with multidirectional laxity, and 2 had posteroinferior instability with multidirectional laxity. An anterior approach was used and a humeral-side capsular shift performed. The mean period of follow-up was 33 months (range, 18-47 months). On the basis of the Rowe system,9 patients had excellent results and 1 had a poor result at final follow-up. The mean score improved from 37.5 to 94 points on the Rowe scale, from 73 to 90.4 points on the Constant scale, and from 1.6 to 7.7 points on a numeric satisfaction scale (P <.001 for all). The one poor result was in the only patient who underwent multiple attempts at open stabilization prior to laser-assisted capsular shrinkage. There were no complications. We conclude that the results of an inferior capsular shift for multidirectional instability are not necessarily adversely affected by a previous failed laser-assisted capsular shrinkage procedure.

Adult↗
PubMedDate not supplied

Shoulder instability related to epileptic seizures.

Epileptic seizures can cause shoulder dislocation and instability, but a characteristic pattern of instability and structural lesions is not well known. We reviewed 34 shoulders in 26 patients in whom the initial dislocation had been caused by an epileptic seizure. All patients were followed up clinically and radiologically for a mean of 10 years (range, 2-21 years) after initiation of treatment. Thirteen patients (17 shoulders) were treated for anterior instability. A large Hill-Sachs lesion was found 12 times and a large glenoid rim fracture 5 times. There were 12 recurrent and 2 locked dislocations. The recurrence rate after the first repair was 47% (8/17 shoulders). The final overall results at a mean follow-up of 10 years (range, 2-12 years) were good in 12 cases, satisfactory in 2, and unsatisfactory in 2. The reoperation rate was 40%. With skeletal reconstruction, 12 of 13 shoulders were stable at final follow-up. Another 13 patients (17 shoulders) were treated for posterior dislocation. A large reverse Hill-Sachs lesion was observed 13 times and a posterior glenoid rim fracture twice. There were 15 locked but only 2 recurrent dislocations. The recurrence rate after repair was 12% (2/17 shoulders). The final outcome at a mean follow-up of 7 years (range, 2-12 years) was good in 11 shoulders and satisfactory in 6. The reoperation rate was 12%. Anterior and posterior dislocations occurred with equal frequency in this series. Large bony lesions were the hallmark finding in this group of patients. Skeletal reconstruction was necessary to obtain clinical stability, especially in the more difficult-to-treat anterior instability.

Adolescent↗
PubMed2002

Neonatal hip instability: results and experiences from ten years of screening with the anterior-dynamic ultrasound method.

AIM: To record the results and experiences from a 10-y screening period with the anterior-dynamic ultrasound method for detecting neonatal hip instability. METHODS: An ultrasonographic improvement of the Palmén/Barlow test was used. The screening programme included 22,047 newborns. Decisions about treatment were made solely on the ultrasound result. RESULTS: It was found that 175 infants (7.9/1000) had at least one unstable hip--dislocated or dislocatable. Dislocated hips were found in 1.1/1000. Dislocatable hips were found in 6.8/1000 but only 1.1/1000 needed treatment. The total frequency of treatment was 2.2/1000. All cases but one were diagnosed before discharge from the maternity ward. The rate of surgery was 0.1/1000 newborns. Girls were more affected than boys, by a ratio of 3:1. Among the affected hips 64.4% were a left hip. CONCLUSION: Neonatal hip instability is always present at birth and can be diagnosed immediately after birth. We have no indications that instability can appear at a later stage. The anterior-dynamic ultrasound screening programme is an efficient tool to diagnose neonatal hip instability and to decide when to begin treatment.

Female↗
PubMed2006

Arthroscopic electrothermal shrinkage of chronic posterolateral elbow instability: good or moderate outcome in 21 patients followed for an average of 2.5 years.

BACKGROUND: The lateral collateral ligament complex is the key structure involved in recurrent elbow instability. Treatment is surgical, by repair or reconstruction of the lateral collateral ligament complex. We evaluated the effect of arthroscopic electrothermal shrinkage for treatment of chronic posterolateral rotator elbow instability. METHODS: 21 patients, median age 32 (24-50) years, suffering from chronic lateral elbow instability underwent arthroscopic electrothermal ligament shrinkage with a bipolar shrinkage probe. All patients were available for follow-up after median 30 (8-48) months. RESULTS: No complications were seen. The Morrey score increased from 40 to 77 points. The result was moderate (50-80 points) in 10 patients, and in the other patients a good result was achieved (80-95 points). The manual stress radiography showed a mean lateral joint opening of 13 (8-18) mm preoperatively. During follow-up, it decreased to 2 (1-4) mm. INTERPRETATION: Our findings suggest that arthroscopic bipolar ligament shrinkage is sufficient for the treatment of chronic posterolateral rotator elbow instability.

Adult↗
PubMed2005

Evidence that both genetic instability and selection contribute to the accumulation of chromosome alterations in cancer.

Cancer cells contain many genetic alterations, and genetic instability may be important in tumourigenesis. We evaluated 58 breast and ovarian cancer cell lines for microsatellite instability (MSI) and chromosomal instability (CIN). MSI was identified in 3/33 breast and 5/25 ovarian cell lines, and 7/8 MSI lines showed an inactivation of mismatch repair. Average ploidy by centromeric fluorescence in situ hybridization (FISH) of MSI (n = 8, average ploidy = 2.65) and microsatellite stable (MSS; n = 7, average ploidy = 3.01) cell lines was not different, due to the presence of three aneuploid MSI lines, and two near-diploid MSS lines. However, the variability of the centromeric FISH data was different between MSI and MSS (P = 0.049). The complexity of structural chromosomal rearrangements was not different between MSI and MSS. Thus, MSI and numerical CIN are not mutually exclusive, and structural CIN occurs independently of MSI or numerical CIN. Dynamic genetic instability was evaluated in three cell lines-MSI diploid (MT-3), MSS diploid (SUM159) and MSS aneuploid (MT-1). Ten clones of each of these cell lines were analysed by centromeric FISH and six-colour chromosome painting. The variation in chromosome number was different among all three cell lines (P < 0.001). MT-3 appeared numerically constant (94% of centromeric FISH signals matched the mode). SUM159 was 88% constant; however, 7% of cells had duplicated chromosomes. MT-1 was 82% constant; most changes were chromosomal losses. The six-colour FISH data showed that SUM159 had more stable structural chromosomal alterations (e.g. chromosomal translocations) compared with MT-3 and MT-1, but had no increase in unstable changes (e.g. chromatid breaks) when compared with MT-3. MT-1 had fewer unstable changes than both MT-3 and SUM159. These data suggest that numerical CIN may contribute to aneuploidy, but that selection plays an important role, particularly for the accumulation of structural chromosomal changes.

Breast Neoplasms↗