Superior Migration Research Articles

New trends in shoulder arthroplasty

Shoulder arthroplasty has undergone an important evolution during the past ten years. Increasing knowledge of normal anatomy and biomechanics has hastened the development of a third generation of shoulder replacements, which will hopefully provide better results for longer time periods. The most important changes in shoulder prosthesis have been the development of systems that address the variability of head-shaft angles and humeral head offset. Improved glenoid components have also resulted from biomechanical and clinical study. The nature of these changes and their clinical significance will be the topic of this review. Lastly, a topic of increasing attention by shoulder surgeons is the condition of anterior and superior migration of the shoulder. This review will discuss the pathophysiology and new treatment options for this condition using arthroplasties.

Negative prognostic factors in managing massive rotator cuff tears.

To investigate the negative prognostic factors in the management of massive rotator cuff tears. Retrospective nonrandomized study. Faculty Practice associated with a major orthopedic teaching hospital. 108 patients who were treated for massive rotator cuff tears were evaluated for an average of 3.2 years posttreatment. There were 58 females and 50 males, with a mean age of 61.3 years. 40 patients underwent conservative nonsurgical management (Group 1), 32 patients underwent arthroscopic debridement (Group 2), and 36 patients underwent primary repair of the rotator cuff (Group 3). A detailed Shoulder Rating Questionnaire was filled out by patients pretreatment and minimal 2 years posttreatment. Overall, Group 1 had 65% excellent or good outcomes, Group 2 had 81%, and Group 3 had 86%. The subgroup of patients in Group 1 who had cortisone injections had a 75% success rate. Negative prognostic factors evaluated are presence of glenohumeral arthritis, decreased passive range of motion, superior migration of the humeral head, presence of atrophy, and external rotation/abduction strength less than 3. The presence of 3 or more of these negative prognostic factors are correlated with poor outcomes in the treatment of massive rotator cuff tears.

Correlation of radiographic and arthroscopic findings with rotator cuff tears and degenerative joint disease

The purpose of this study was to identify early signs of rotator cuff tear and glenohumeral articular cartilage degeneration by using conventional radiography. A non-weighted anteroposterior oblique and a weighted active abduction view were evaluated for superior humeral migration and matching degenerative changes at the inferolateral acromion and superior aspect of the greater tuberosity in 40 patients who underwent shoulder arthroscopy. Measurements of the glenohumeral distance were performed. Surgical reports were reviewed to determine rotator cuff and glenohumeral articular cartilage status. Matching degenerative changes correlate with complete rotator cuff tear (P =.04); superior migration does not. Severe glenohumeral cartilage loss correlates with narrowing of the superior joint space on the anteroposterior oblique radiograph (P =.02) and with narrowing of the mid joint space on the active abduction view (P =.05). Both glenohumeral articular cartilage degenerative change and rotator cuff injury, before formation of typical sequelae of chronic rotator cuff tear, can be detected with the use of conventional radiography. (J Shoulder Elbow Surg 2001;10:428-33.)

From Postsurgical Imaging…

Marked superior and inferior migration of a dynamic plate after multilevel anterior corpectomy and fusion with posterior wiring (Fig. 1a) (Fig. 1b) 1 Epstein N.E. Circumferential surgery for the management of ossification of the posterior longitudinal ligament. J Spinal Disord. 1998; 11: 200-207 Crossref PubMed Scopus (53) Google Scholar , 2 Epstein N.E. The value of anterior cervical plating in preventing vertebral fracture and graft extrusion following multilevel anterior cervical corpectomy with posterior wiring/fusion. J Spinal Disord. 2000; 13: 9-15 Crossref PubMed Scopus (62) Google Scholar , 3 Epstein N.E. The management of one level anterior cervical corpectomy with fusion employing Atlantis hybrid plates preliminary experience. J Spinal Disord. 2000; 13: 324-328 Crossref PubMed Scopus (24) Google Scholar Fig. 1A 59-year-old man with moderate to severe spastic cervical myeloradicular syndrome (Nurick grade IV), caused by continuous ossification of the posterior longitudinal ligament was treated with anterior corpectomy C3–7 and anterior and posterior fusion. Fixation posteriorly was by wiring and anteriorly by a “dynamic” ABC Aesculap 80-mm-long plate. Such plates are unique in that the screws themselves can migrate up to 10 mm within the slots of the plate and because the “variable” screws are capable of toggling up to 34 degrees. (a) Lateral and (b) anteroposterior radiographs, taken 6 weeks after surgery, show that the plate had migrated 6 cm cephalad and 4 mm caudad within the slots of the plate (curved arrows). The screw angles superiorly and inferiorly remained at approximately 17-degree angles (double arrows, left panel). Four months after surgery, the patient appeared to have fused by three-dimensional computed tomography and by flexion/extension lateral stress films. Neurologically, he improved three Nurick grades to minimal residual (Nurick I) View Large Image Figure Viewer

Arthroscopic resection of the distal aspect of the clavicle with concomitant subacromial decompression.

Arthroscopic subacromial decompression and arthroscopic resection of the acromioclavicular joint as separate procedures have been well documented. However, there is little information on the success rate of resection with concomitant decompression. In this study, we retrospectively evaluated the results of a consecutive group of patients who underwent arthroscopic resection of the acromioclavicular joint with concomitant subacromial decompression. We evaluated the surgical results in thirty-one consecutive patients (thirty-two shoulders) with acromioclavicular pathology with concomitant subacromial impingement. The mean age of the patients at the time of surgery was thirty-six years (range, eighteen to sixty-seven years). Twenty-five patients, including four professional athletes, were actively involved in sports activities. The mean duration of follow-up was four years and ten months (range, three to eight years). The follow-up examination included clinical evaluation, chart review, radiographic analysis, and isokinetic testing of both upper extremities. Of the twenty-five patients who participated in sports, twenty-two (including the four professional athletes) returned to their previous level of sports activity. Twenty-six patients had no pain, three reported mild pain on strenuous repetitive overhead activity, two (both weight-lifters) had occasional pain in the acromioclavicular joint and the lateral aspect of the shoulder with bench-pressing, and two (both baseball players) had mild pain in the posterior aspect of the shoulder with throwing. All of the patients were satisfied with the results. In the absence of a complete rotator cuff tear, isokinetic strength-testing of both upper extremities failed to demonstrate any weakness of the involved shoulder. The mean functional score for individual activities was 2.7 points (range, 2.1 to 3.0 points) preoperatively and 3.9 points (range, 3.6 to 4.0 points) postoperatively (p = 0.0001). No patient had superior migration of the clavicle. The amount of distal clavicular resection averaged 9 mm (range, 7 to 15 mm). One patient had heterotopic ossification at the resection site, with mild pain on direct palpation of the acromioclavicular joint and on strenuous overhead activity. Five patients had calcification at the anterior deltoid insertion into the acromion that was asymptomatic, with no impingement on overhead activity and no pain on direct palpation. We found excellent results with arthroscopic resection of the acromioclavicular joint and concomitant subacromial decompression. When this procedure is performed on properly selected patients, the results are similar to those of an open approach.

Latissimus dorsi transfer in the treatment of irreparable rotator cuff tears

Two male patients, aged 51 and 57 years, presented with complaints of loss of shoulder elevation and anterior shoulder pain. No active elevation and abduction of the shoulder were observed. Drop arm sign was positive. Plain radiographs revealed superior migration of the humeral head. Magnetic resonance imaging showed massive tears of the supraspinatus and infraspinatus tendons. Latissimus dorsi tendon transfer was performed with the diagnosis of irreparable, massive rotator cuff tears. Different results were obtained from the patients, suggesting that patient selection is crucial for a successful outcome. It seems difficult to obtain satisfactory results by latissimus dorsi transfer in patients with total pseudoparalysis. Nevertheless, the results may be successful in primary rotator cuff tears, in cases without deltoid dehiscence, and in those with intact subscapularis insertion.

Bipolar hip arthroplasty as a salvage treatment for instability of the hip.

Recurrent instability of the hip in the absence of an identifiable cause is a challenging problem. It has been proposed that bipolar hip arthroplasty may have a role in the treatment of these complex cases. The purpose of our study was to evaluate the results of bipolar hip arthroplasty for the treatment of recurrent instability of the hip in a series of patients at our institution. We reviewed the records of twenty-seven patients who had undergone bipolar hip arthroplasty as a salvage procedure for the treatment of recurrent instability of the hip after total hip replacement. All patients had undergone at least two, and a mean of three, stabilizing operative procedures on the hip prior to the bipolar arthroplasty. The mean duration of follow-up was five years (range, two to twelve years), with no patient lost to follow-up. There were six deaths, of unrelated causes. Bipolar arthroplasty prevented redislocation in twenty-two hips (81 percent). At the time of final follow-up, twenty-five patients (93 percent) had a stable hip. Five patients (19 percent) had had episodes of subluxation or dislocation following the bipolar arthroplasty. Two of these patients had only a single episode of dislocation that was treated successfully by immobilization. Two of the remaining three patients required a reoperation because of the instability. The hip was stabilized with the use of a constrained cup prosthesis in one of these patients, and the other patient eventually required resection arthroplasty. The third patient had continuing instability but improved function and pain relief, and a reoperation was not performed. There were a total of seven reoperations; these included revision because of disassembly of the cup in one hip, revision bipolar arthroplasty because of continuing instability in two, resection arthroplasty because of deep infection in two, revision arthroplasty because of recalcitrant groin pain in one, and revision arthroplasty because of deep infection and superior migration of the implant in one. The Harris hip score improved significantly, from a mean of 24 points (range, 5 to 45 points) preoperatively to a mean of 55 points (range, 35 to 80 points) postoperatively (p < 0.05). We believe that, despite some potential problems, bipolar hip arthroplasty can have a role in the salvage management of recurrent instability of the hip in patients in whom other stabilization procedures have failed.

Acetabular revision with use of a bilobed component inserted without cement in patients who have acetabular bone-stock deficiency.

Massive deficiency of acetabular bone stock is a challenging problem in the increasing number of patients who need a revision of a failed hip arthroplasty. The bilobed cup has been presented as one alternative reconstruction technique for hips with extensive acetabular bone loss. The purpose of this study was to assess the results with use of a bilobed acetabular component inserted without cement for revision reconstruction in hips with acetabular bone deficiency in order to clarify the indications for its use and to identify the factors that influence the clinical and radiographic outcome. Forty-one hips in thirty-eight patients had an acetabular revision with a bilobed acetabular component inserted without cement between December 1991 and December 1995. These hips were a subset of the 414 hips treated with an acetabular revision during the same period of time. One patient was lost to follow-up, and one died during the study period. Two patients who could not return for radiographic evaluation completed questionnaires. The remaining thirty-four patients (thirty-seven hips) were evaluated radiographically and clinically and were followed for an average of forty-one months (range, twenty-four to sixty-six months). Radiographic analysis demonstrated an improvement in the average vertical displacement of the hip center. At the time of the latest follow-up examination, 76 percent (twenty-eight) of the thirty-seven cups were stable, 8 percent (three) were probably unstable with a change in the screw position but no definite migration of the cup, and 16 percent (six) were unstable. Eight of the nine loose or probably loose components were in patients who had more than two centimeters of superior migration of the component and disruption of Kohler's line on preoperative radiographs. Additionally, implants were more likely to become unstable (demonstrating more than 4 degrees of change in the abduction angle or more than four millimeters of radiographic migration) when the inferior aspect of the component did not extend to or distal to the interteardrop line, which indicated that the component was undersized. On the basis of our early rate of probable or definite loosening of 24 percent (nine of thirty-seven cups) and the technical difficulties involved, we do not recommend the routine use of this component. We believe that this device is indicated when a patient has an oblong-shaped acetabular defect and the surgeon wants to correct an elevated hip center. However, the medial wall of the acetabulum (Kohler's line) should be intact if the failed component has migrated more than two centimeters. An alternative reconstruction technique, such as use of a structural allograft with or without an acetabular cage, is also an option in this situation.

Glenohumeral motion in patients with rotator cuff tears: A comparison of asymptomatic and symptomatic shoulders

The purpose of this study was to determine whether there was a relationship between altered scapular plane glenohumeral kinematics end shoulder pain. Subjects were divided into 3 groups: normal volunteers (n = 10), patients with symptomatic rotator cuff tears severe enough to warrant surgery (n = 10), and subjects with no symptoms who had tears documented on magnetic resonance imaging and normal examination (n = 10). Humeral kinematics were observed with a computer-enhanced modification of the Poppen and Walker technique. Scapular plane x-ray films were obtained at 0 degree, 30 degrees, 60 degrees, 90 degrees, 120 degrees, and 150 degrees of elevation. Measurements were made by 3 independent observers blinded to the diagnosis, and data interpretation was performed based on mean values for independent observers. Results showed a high degree of interobserver and intraobserver reliability (coefficients = 0.96 and 0.95, respectively). The symptomatic and asymptomatic groups showed progressive superior translation of the humeral head on the glenoid with increasing arm elevation. The normal group, in contrast, maintained a constant center of rotation along the geometric center of the glenoid. Symptomatic and asymptomatic rotator cuff tear groups showed superior head migration from 30 degrees to 150 degrees, which was significantly different from those seen in the normal group. No significant difference between the symptomatic and asymptomatic groups was demonstrated with the small numbers used in this study. The presence of a rotator cuff tear was associated in a disruption of normal glenohumeral kinematics in the scapular plane. Because significant superior migration of the humeral head was seen in both the asymptomatic and symptomatic rotator cuff groups, painless and normal shoulder motion is possible in the presence of abnormal glenohumeral kinematics. Abnormal glenohumeral kinematics alone was not an independent factor, which could explain the occurrence of symptoms.

The management of severe acetabular bone loss using structural allograft and acetabular reinforcement devices

The cases of 37 acetabular reconstructions in 35 patients with major structural pelvic bone loss were reviewed. At an average follow-up of 7.1 years, patients rated their results as excellent in 12 cases (32.4%), good in 22 (59.5%), fair in 2 (5.4%), and poor in 1 (2.7%). Thirty-four cases (91.9%) were classified as a clinical success. Thirty-six allografts (97.3%) had radiographic evidence of full incorporation. Of the unrevised hips, 1 (2.7%) was classified as definitely loose, 2 (5.4%) as probably loose, and 4 (10.8%) as possibly loose. One revision of an acetabular component was required because of late sepsis. This is the first reported series on the use of acetabular reinforcement devices with solid bulk allograft covering more than 50% of the socket. The allograft is protected in the early postoperative period, superior migration of the cup is virtually eliminated as a complication, and the incidence of aseptic loosening is greatly diminished.

Radiographic evaluation of glenohumeral kinematics: A muscle fatigue model

The purpose of this study was to document the effect of muscle fatigue on glenohumeral kinematics. Twelve male volunteers without shoulder disease and with an average age of 27 years were studied. Glenohumeral anteroposterior radiographs were taken at 45° intervals as the arm was abducted in the plane of the scapula from 0° to 135°. This series of radiographs was performed both before and immediately after the subject performed a series of deltoid and rotator cuff fatiguing exercises. The average humeral head position or translation before and after muscle fatigue for each arm angle was compared. For all subjects, before fatigue, the position of the humeral head was below the center of the glenoid for all angles of abduction. There was essentially no change in position of the humeral head in the prefatigue state, as the arm was abducted from 0° to 135° with no more than an average 0.3 mm of total humeral head excursion. After fatigue, excursion of the humeral head increased to an average of 2.5 mm between the tested positions. The position of the humeral head with the arm at 0° of abduction was lower or had migrated inferiorly compared with the rested state, with an average 1.2 mm significant increase in inferior translation. With the initiation of abduction, the humeral head demonstrated significant superior migration or translation in all positions tested. This result has important implications for conservative treatment of shoulder impingement and underscores the importance of rehabilitation to maximize the endurance and strength of the rotator cuff musculature.

Migration and failure of the Mecron screw-in acetabular prosthesis

Early results with the Mecron prosthesis have been variable. We report our experience with this prosthesis at medium- to long-term follow-up. At 5 to 9 years after surgery, 43 patients (49 implants) were reviewed. Radiographic measurements of superior migration, alteration in the opening angle, and thread engagement were made. The failure rate was very high, 33% having been revised or awaiting revision. Of the remainder, 80% had migrated, 86% had changes in the opening angle, and 65% had fewer threads engaged. Many have low-grade symptoms insufficient to merit revision, but the extent of loosening makes eventual revision likely. We feel this represents an example of a new design gaining widespread usage before adequate follow-up studies.

Surface modification based on Si-O and Si-C sublayers and a series of N-substituted acrylamide top-layers for capillary electrophoresis.

Two approaches were used to prepare a series of surface-modified capillaries. In the first, a sublayer was formed by coupling gamma-methacryloxypropyltrimethoxysilane to the surface silanol groups forming an SI-O bond; a top layer was then formed by polymerizing acrylamide in the capillary, which reacted with the sublayer. In the second approach, a sublayer was formed by silanol chlorination, followed by Grignard coupling of vinylmagnesium bromide to form an Si-C bond at the surface; a top layer was formed by polymerizing either acrylamide (AA), dimethylacrylamide (DMA), N-acryloylaminoethoxyethanol (AAEE), or N-acryloylaminopropanol (AAP) onto the sublayer. The Si-Cpoly(AA) capillaries were more stable and produced an approximately 10-fold lower electroosmotic flow compared to the Si-O-poly(AA) capillaries. The Si-C sublayer was used to compare the performance of all four top layers. Electroosmotic flow decreased in the order: Si-O-poly(AA), Si-C-poly(AA), Si-Cpoly(AAEE), Si-C-poly(DMA), and Si-C-poly(AAP). Si-C-poly(AA) showed evidence of irreversible degradation at pH 9 already after 40-50 runs. Si-C-polyAAP-coated capillaries demonstrated superior efficiency and migration time reproducibility for a number of alkaline proteins and for fluorescently labeled ovalbumin. Excellent performance was maintained, in the case of poly(AAP), for a least 300 runs (of 30 min duration) at pH 9.0.

Total hip arthroplasty with use of an acetabular reinforcement ring in patients who have congenital dysplasia of the hip. Results at five to fifteen years.

The purpose of our study was to examine the clinical and technical problems associated with reconstruction of the hip in patients who had congenital dysplasia and to offer recommendations for their solution. We reviewed the records on 123 consecutive total hip arthroplasties that had been performed by one of us (M. E. M.), between 1981 and 1986, for the treatment of coxarthrosis due to congenital dysplasia of the hip. A minimum of five years of follow-up was required for inclusion in the study. The study group consisted of seventy patients who had had a total of eighty-seven reconstructions. According to the classification of Crowe et al., eleven hips had type-IV acetabular dysplasia; sixty-five, type-II; and eleven, type-II. Acetabular reconstruction was performed with use of the Müller acetabular roof-reinforcement ring and a polyethylene cup, which was inserted with cement. Autologous graft from the femoral head was used in forty-two hips. Femoral reconstruction was performed with use of the Müller straight-stem component for congenital dysplasia of the hip in eighty hips and with use of a standard Müller straight-stem component in seven hips. At an average of 9.4 years (range, five to fifteen years) postoperatively, the result was described as excellent for sixty hips (69 per cent), as good for twenty-three (26 per cent), as fair for two (2 per cent), and as poor for two. Nine (10 per cent) of the hips had been revised. One revision had been performed because of aseptic loosening of the acetabular component; one, because of aseptic loosening of the femoral component; one, because of aseptic loosening of both components; and six, because of infection. Of the unrevised hips, three had had superior migration of the acetabular component of less than five millimeters, and mild protrusion had developed in one. Two hips had a continuous radiolucent line around the acetabular construct. Two hips had had subsidence of the femoral stem of less than three millimeters; one had a complete, non-progressive radiolucent line at the bone-cement interface; and four had a radiolucent line at the proximal part of the bone-cement interface. Six hips had evidence of endosteal osteolysis. Six hips had grade-III or IV heterotopic ossification according to the system of Brooker et al. These results compare favorably with others in the literature. We recommend restoration of the anatomical hip center with the use of an acetabular roof-reinforcement ring and a polyethylene cup inserted with cement for the reconstruction of a deficient acetabulum. The acetabular reinforcement ring prevents resorption of bone graft and migration of the cup, which are major causes of failure of the cup in patients who have had a reconstruction of a deficient acetabulum. Bone graft should be used medially and superiorly as needed to augment bone stock notably. Cement should not be used to fill acetabular defects as we believe that it contributes to aseptic loosening.

5 Depressor function of the biceps to superior migration of the humeral head in shoulders with rotator cuff tears

5 Depressor function of the biceps to superior migration of the humeral head in shoulders with rotator cuff tears

The use of adrenaline in reduction mammaplasty

Conventional rhytidoplasty is somewhat limited in its effectiveness by the need to conceal the incisions that allow access to the affected area. The coronal incision, commonly used in such procedures, results in an inevitable posterior and superior migration of the hairline, which stigmatizes operated patients. This paper presents a new approach to rhytidoplasty by modifying the incisions in both temporal and frontal areas. The modification consists of performing the incisions anterior to the hairline in that area, going around the sideburns and following upward to the level of the supraorbital rim, carried out either superior or inferior to the brow. If lifting of the brow is desired the incision is placed superior to it, if not it is placed below the brow and may coincide with the upper blepharoplasty incisions. Additionally the incisions from both sides may be united in the midline, if excision of glabellar wrinkles is needed. The use of this approach allowed traction to be placed as needed without the restrictions imposed by the position of the temporal hairline or sideburns. Moreover greater control over the position of the brow was achieved. Therefore, greater effectiveness was attained without jeopardizing the naturalness of the result.

Depressor Function of the Biceps to Superior Migration of the Humeral Head in Shoulders with Rotator Cuff Tears

Depressor Function of the Biceps to Superior Migration of the Humeral Head in Shoulders with Rotator Cuff Tears

Occipital-cervical fusion

Stabilization of the occipital-cervical region is a less common procedure than fusion of the subaxial cervical spine. Fortunately fusion rates are relatively high (over 90%) and complication rates acceptable. The most common indications for occipital-cervical fusion are superior migration of the odontoid region or cranial settling in rheumatoid arthritis, instability caused by tumor or other destructive process, or traumatic injury to this region. Several techniques are used to accomplish fusion to the occiput. The triple-wire technique is safe and works well for relatively stable situations, whereas plate-and-screw or rod techniques may be used for more unstable spines. All should have supplemental autogenous bone graft and postoperative immobilization, usually a halo vest.

Orthopedic and interventional applications at low field MRI with horizontally open configuration. A review.

The recently introduced horizontally open configuration imagers allow imaging of knee, hip or shoulder during whole range of motion, which is not possible in conventional MR imagers. Special joint motion devices can be used to provide accurate and reproducible studies. In cervical spine, functional MR imaging may be useful in evaluating alarligament stability in patients with late sequelae of a whiplash injury, and in patients with rheumatoid arthritis who are clinically suspected of having a cervical myelopathy or superior migration of the odontoid process. In shoulder, full range of motion abduction study may be helpful in assessing the supraspinatus tendon impingement. To evaluate patellofemoral malalignment, quadriceps loading is recommended since associated contracting muscles and related soft tissue structures can be evaluated. The position of the femoral head relative to the acetabulum during different positions can be assessed. Open-configuration scanners provide an access to patients during scanning procedure, and therefore permit interventional procedures to be monitored with MRI. Such interventions include aspiration cytology/biopsy and different drainage procedures.

Modified medial displacement and valgus osteotomy for unstable intertrochanteric fractures

We have described previously a modification of the medial displacement and valgus osteotomy of Dimon and Hughston to manage non-unions of intertrochanteric fractures. In this study, we have used the same modification to manage fresh, unstable intertrochanteric fractures. Eighty-seven patients underwent this procedure. Four died within 4 months. The remaining 83 patients were evaluated over a period ranging from 4 to 49 months. There was a low complication rate with this method. They included one perforation of the femoral head, one post operative infection that recurred as a deep infection, one partial superior migration of the implant, one varus fixation with noticeable shortening and two cases where the trochanteric wire had snapped. In the others, the hip movement, abductor function, functional recovery and rate of union (8-12 weeks) were good. The method permits early weight-bearing and avoids some of the problems seen with anatomical fixation of unstable fractures using the sliding screw plate. We feel that medial displacement and valgus osteotomy with an angled blade plate has a definite role in the treatment of unstable intertrochanteric fractures in some situations.