Signs Of Impingement Research Articles

Anterior femoro-acetabular impingement. Radiological signs in young patients diagnosed with hip osteoarthritis

To determine the incidence of the characteristic radiological signs of anterior femoro-acetabular impingement (AFAI) in young patients diagnosed with idiopathic hip osteoarthritis. Retrospective review of the clinical records of patients under 50 years of age diagnosed with idiopathic hip osteoarthritis between 1995 and 2000. The functional assessment of the hip was made by means of the Merle D’Aubigne scale. The radiological study that revealed the presence of the figure-of-8 sign and the head/neck bump sign. The hip joint was evaluated by means of Tönnis’ scale. Fifty-one (43%) of the 121 patients under 50 were diagnosed with idiopathic hip osteoarthritis. We reviewed 45 hips. The mean age in this group was 44.5 years (range: 30-50). The mean value obtained on the Merle d’Aubinge scale was 16 (range: 12-17). In 10 hips (22%) the figure-of- 8 sign was observed, in 26 (58%) the head/neck bump sign was observed. Both signs were observed in 6 cases (13%). Thirty hips (66%) presented with at least one of these radiological signs. In 18 hips (60%) lytic images were seen in the proximal femur. Seventy percent of patients that had at least one of the characteristic signs of FAI were grade I on the Tonnis classification; the remaining 30% were grade II. In our series, 66% of patients diagnosed with idiopathic hip osteoarthritis presented, at the time when the diagnosis was made, radiological signs characteristic of AFAI. Also, AFAI could be construed as the cause for the primary hip osteoarthritis in some of the patients. Determinar la incidencia de los signos radiológicos característicos del atrapamiento fémoro-acetabular anterior (AFA) en pacientes jóvenes diagnosticados de coxartrosis idiopática. Revisión retrospectiva de historias clínicas de los pacientes menores de 50 años diagnosticados de coxartrosis idiopática entre los años 1995 y 2000. Evaluación funcional de la cadera con la escala de Merle D’Aubigne. Estudio radiológico, donde se observa la presencia del signo del lazo y el signo de la giba, así como la valoración de la articulación coxofemoral con la escala de Tönnis. Cincuenta y uno (43%) de los 121 pacientes menores de 50 años fueron diagnosticados de coxartrosis idiopática. Revisamos 45 caderas, con una edad media del grupo de 44,5 años (30-50). El promedio de los valores obtenidos en la escala de Merle d’Aubinge fue de 16 (12-17). En 10 caderas (22%) se observó el signo del lazo, en 26 (58%) se evidenció el signo de la giba, y en seis casos ambos signos (13%). En 30 caderas (66%) se observaron algunos de estos signos radiológicos. En 18 (60%) caderas se apreciaron imágenes líticas en el fémur proximal. El 70% de los pacientes en los que se observó alguno de los signos característicos del AFA presentaba un grado I en la clasificación de Tönnis, el 30% restante presentó un grado II. En nuestra serie un 66% de los pacientes diagnosticados de coxartrosis idiopática presentaban, en el momento del diagnóstico, signos radiológicos característicos de AFA. Algunos de los pacientes diagnosticados de coxartrosis primaria podrían corresponder a un AFA como causa inicial de su coxartrosis.

Effect of the Scapula Reposition Test on Shoulder Impingement Symptoms and Elevation Strength in Overhead Athletes

Two group, repeated measures design. To determine whether manually repositioning the scapula using the Scapula Reposition Test (SRT) reduces pain and increases shoulder elevation strength in athletes with and without positive signs of shoulder impingement. Symptom alteration tests may be useful in determining a subset of those with shoulder pathology who may benefit from interventions aimed at improving scapular motion abnormalities. One hundred forty-two college athletes underwent testing for clinical signs of shoulder impingement. Tests provoking symptoms were repeated with the scapula manually repositioned into greater retraction and posterior tilt. A numeric rating scale was used to measure symptom intensity under both conditions. Isometric shoulder elevation strength was measured using a mounted dynamometer with the scapula in its natural position and with manual repositioning. A paired t test was used to compare the strength between positions. The frequency of a significant increase in strength with scapular repositioning, defined as the minimal detectable change (90% confidence interval), was also assessed. Of the 98 athletes with a positive impingement test, 46 had reduced pain with scapular repositioning. Although repositioning produced an increase in strength in both the impingement (P=.001) and non-impingement groups (P=.012), a significant increase in strength was found with repositioning in only 26% of athletes with, and 29% of athletes without positive signs for shoulder impingement. The SRT is a simple clinical test that may potentially be useful in an impairment based classification approach to shoulder problems.

Small full-thickness tears do well ten to thirteen years after arthroscopic subacromial decompression

A consecutive series of 181 patients with clinical signs of subacromial impingement underwent arthroscopic subacromial decompression (ASD). All patients had the same surgical procedure, and all pathological findings at the arthroscopy were recorded. Ten to 13 years (mean, 11.2) after the procedure, 162 patients (91%) were available for follow-up consisting of clinical examination and the Constant-Murley and DASH scores. The overall mean value of the age correlated Constant score was 77 points. Men had significantly better Constant score than women. The state of the rotator cuff at the index procedure was found to affect the outcome significantly. Patients with isolated full-thickness supraspinatus tears had the best results, followed by those with partial tears, intact cuffs, or large tears involving more than 1 tendon. ASD in the treatment of subacromial impingement yields good long-term results. Small full-thickness supraspinatus tears had the best results, indicating that the ASD might prevent further cuff deterioration and that repair of these lesions may be unnecessary.

Arthroscopic Offset Restoration in Femoroacetabular Cam Impingement: Accuracy and Early Clinical Outcome

The purpose of this study was to determine the accuracy of arthroscopic restoration of femoral offset as well as the early clinical outcome of arthroscopic debridement and femoral offset restoration and whether there is a correlation between accuracy and outcome. Twenty-two patients with symptomatic femoroacetabular cam impingement underwent arthroscopic correction of the femoral offset and debridement. The alpha angle was measured with magnetic resonance imaging preoperatively and postoperatively for quantification of the offset, and the clinical status was determined by documenting the impingement sign, range of motion, intensity of pain on a visual analog scale, Nonarthritic Hip Score, and complications preoperatively and 6 months postoperatively. The alpha angle improved from a mean of 75 degrees to 54 degrees. Internal rotation increased from a mean of 5 degrees to 22 degrees, flexion increased from a mean of 107 degrees to 124 degrees, and the pain score decreased from a mean of 5.8 to 1.4. The Nonarthritic Hip Score increased from a mean of 49 to 74 points. No major complications were encountered. Patients with early osteoarthritis did substantially worse than those without it. The alpha angle did not correlate with any clinical outcome measure. The femoral offset can be precisely restored via an arthroscopic technique in the treatment of femoroacetabular cam impingement. The early clinical outcome of arthroscopic offset restoration and debridement is good in patients with no or only mild osteoarthritis. The accuracy of correction is not correlated with the early clinical outcome. Level IV, therapeutic case series.

Transosseous Suture Fixation of Proximal Humeral Fractures

The optimal treatment of displaced fractures of the proximal part of the humerus remains controversial. We evaluated the long-term functional and radiographic results of transosseous suture fixation in a series of selected displaced fractures of the proximal part of the humerus. Over an eleven-year period, a consecutive series of 188 patients with a specifically defined displaced fracture of the proximal part of the humerus underwent open reduction and internal fixation with transosseous sutures. Twenty patients were lost to follow-up and three died before the time of follow-up, leaving a cohort of 165 patients (ninety-four women and seventy-one men; mean age, fifty-four years) available for the study. Forty-five (27%) of the injuries were four-part fractures with valgus impaction; sixty-four (39%) were three-part fractures; and fifty-six (34%) were two-part fractures of the greater tuberosity, thirty-six (64%) of which were associated with anterior dislocation of the shoulder. All fractures were fixed with transosseous, nonabsorbable, number-5 Ethibond sutures. Associated rotator cuff tears detected in fifty-seven patients (35%) were also repaired. Over a mean follow-up period of 5.4 years, functional outcome was assessed with the Constant score. Follow-up radiographs were assessed for fracture consolidation, malunion, nonunion, heterotopic ossification, and signs of impingement, humeral head osteonecrosis, and degenerative osteoarthritis. All fractures, except for two three-part fractures of the greater tuberosity, united within four months. The quality of fracture reduction as seen on the first postoperative radiograph was regarded as excellent/very good in 155 patients (94%), good in seven (4%), and poor in three (2%). Malunion was present in nine patients (5%) at the time of the last follow-up; six of the nine had had good or poor initial reduction and three, excellent/very good reduction. Humeral head osteonecrosis was seen in eleven (7%) of the 165 patients; four demonstrated total and seven, partial collapse. Fifteen patients had heterotopic ossification, but none had functional impairment. Four patients had signs of impingement syndrome, and two had arthritis. At the time of the final evaluation, the mean Constant score was 91 points, and the mean Constant score as a percentage of the score for the unaffected shoulder, unadjusted for age and gender, was 94%. The clinical and radiographic results of this transosseous suture technique were found to be satisfactory at an average of 5.4 years postoperatively. Advantages of this technique include less surgical soft-tissue dissection, a low rate of humeral head osteonecrosis, fixation sufficient to allow early passive joint motion, and the avoidance of bulky and expensive implants.

Influence of Femoroacetabular Impingement on Results of Hip Arthroscopy in Patients with Early Osteoarthritis

To ascertain whether better results could be obtained using hip arthroscopy, we retrospectively reviewed the radiographic and clinical aspects of anterior femoroacetabular impingement in 43 patients diagnosed with early osteoarthritis with acetabular labral tears who previously had arthroscopic treatment. The average followup was 50 months. The patients were divided into two groups: patients who had no osteoarthritis seen on simple radiographs, but had degenerative changes of the labrum and cartilage seen on magnetic resonance arthrograms and arthroscopy, and patients who had osteoarthritic findings seen on simple radiographs. Both groups were examined retrospectively for signs of anterior femoroacetabular impingement at the acetabulum and proximal femur. Postoperative improvement was evaluated using the Japanese Orthopaedic Association pain score. Six of 21 patients in Group I and 12 of 22 of patients in Group II showed radiographic evidence of femoroacetabular impingement. The score improved from 0.76 preoperatively to 2.38 postoperatively in Group I and from 0.75 preoperatively to 1.90 postoperatively in Group II. Arthroscopic débridement produced improved results seen during short-term and midterm followups. However, in patients with femoroacetabular impingement the results were considered inadequate. We found that arthroscopic treatment of osteoarthritis of the hip fails if there is detectable femoroacetabular impingement.

Diagnostic Accuracy of Clinical Tests for the Different Degrees of Subacromial Impingement Syndrome

The authors evaluated the utility of eight clinical tests commonly used in the diagnosis of rotator cuff disease (RCD). Specifically, they calculated diagnostic values (sensitivity, specificity, predictive values, likelihood ratios, and posttest probabilities) for the Neer impingement sign, Hawkins-Kennedy impingement sign, painful arc sign, supraspinatus muscle strength test, Speed's test, cross-body adduction test, drop-arm sign, and infraspinatus muscle strength test across 3 degrees of severity of RCD: bursitis without a rotator cuff tear, partial-thickness rotator cuff tears, and full-thickness rotator cuff tears.

EFFECT OF EXERCISE AND MANUAL PHYSICAL THERAPY ON SHOULDER FUNCTION AMONG SLAUGHTERHOUSE WORKERS WITH SHOULDER IMPINGEMENT SYNDROME.

This study was carried out in a slaughterhouse in Zagazig City during the year 2005-2006 among a group of 115 slaughterhouse workers selected randomly and performing sustained intensive manual work. Another group of 80 clerks working in Zagazig Faculty of medicine performing light manual work was selected randomly as a control group. The study was done in 2 stages : The 1st stage was a comparative cross-sectional study, aiming to determine the prevalence of shoulder impingement syndrome ( SIS) among the study workers.The 2nd stage was an intervention study, done to assess the effect of exercise and manual physical therapy program on shoulder function among workers with shoulderimpingement syndrome. A total number of one-hundred and ninety five workers were interviewed using a preconstructed questionnaire. Those workers who had recurrent 143 Egyptian Journal of Occupational Medicine, 2007; 31 (1) : 143 - 162144 El-Laithy N. et. al shoulder pain during the previous 3 months or more were subjected to standardizedphysical examination using impingement sign, assessment of shoulder function and magnetic resonance imaging to those clinically diagnosed as SIS. Also an intervention program of exercise and manual therapy for a period of 6-weeks was carried out to those workers with SIS.he results revealed that the prevalence of SIS was higher among the laughterhouseworkers (13.9 % ) compared to the control workers(2.5%). SIS symptoms and signs were more frequently recorded among the slaughterhouse workers when compared with the controls. Also among those currently complaining of SIS symptoms or those who has had SIS signs, only 15.6% and 2.5% have positive impingement sign among slaughterhouse workers and their controls respectively. The most reliable findings of magnetic resonance imaging were the presence ofindentations upon the subacromial fat denoting impingement in 12 patients (66.7%),supraspinatus tendonitis with indentation upon subacromial fat denoting impingement in 4 patients (22.2%) & left supraspinatus tear in 2 patients (11.1%) from 18 slaughterhouse workers diagnosed clinically as SIS and supraspinatus tendonitis with impingementin 2 patients (100.0%) from the control group with a total percentage of 13.9% and 2.5% workers with SIS among slaughterhouse workers and their controls respectively. Studying some personal and occupational factors thought to be related to the prevalence of SIS revealed that, SIS was prevalent in middle aged workers who smoke and were worked in the current occupation for more than ten years.The results of the intervention program illustrated that there were significant improvement in range of motion, pain, strength and function of the shoulder in workers with SIS after 6- weeks of exercise and manual physical therapy program.In conclusion, sustained intensive manual work such as in slaughterhouse workers was associated with high frequency of SIS. A 6 week exercise with manual physicaltherapy program in patients with SIS was resulted in improvement of range of motion, pain and function of the shoulder. So, work organization especially reduction of exposure time and early intervention are needed in tasks in which there are combinations of force, repetition and sustained arm elevation.

Clinical Features and Arthroscopic Findings of Partial Thickness Rotator Cuff Tears

Pur p ose: To compare the clinical features of partial thickness rotator cuff tears according to location of the tear and to classify the partial thickness rotator cuff tears based on arthroscopic findings. Mat e r ia ls and Met h ods: This study evaluated 138 patients who were arthroscpically proven to be partial thickness rotator cuff tears. Three groups were identified; 56 in the articular side tear, 58 in the bursal side tear, 24 in the both sides tear. The comparison included preoperative clinical features such as pain, range of motion and impingement sign. T he partial thickness rotator cuff tears were classified according to the arthroscopic findings.

Comprehensive Morphologic Evaluation of the Hip in Patients with Symptomatic Labral Tear

A torn acetabular labrum is a well-documented source of hip pain, but the mechanism of injury is debated because the relationship between the bone morphology and labral tears is poorly understood. We compared hips with and without labral abnormalities to determine the relative incidence of morphologic abnormalities. The study group consisted of patients with a labral tear confirmed by arthroscopy or arthrotomy at the time of open débridement or periacetabular osteotomy. We compared the affected hip with the contralateral, unaffected hip to ascertain signs of hip dysplasia and impingement. We observed differences in the center edge angle, acetabular depth to width index, acetabular index of elevation, femoral head extrusion, lateral and superior subluxation, Sharp's angle, peak to edge distance, and acetabular retroversion. Similar differences occurred in the subgroup analyses. Symptomatic labral tears correlated with abnormal hip morphology as reflected by radiographic measurements of dysplasia and impingement. This relationship occurred in patients with hip dysplasia and patients without obvious femoral head uncovering. Our findings suggest abnormal hip morphology may be a risk factor for labral tears.

The effects of a six week scapular muscle exercise programme on the muscle activity of the scapular rotators in tennis players with shoulder impingement—A pilot study

Introduction Shoulder impingement is a common pathology in overhead athletes. Scapular dysfunction is regularly implicated in the pathogenesis of shoulder impingement and research has demonstrated altered scapular muscle activity in subjects with impingement. Clinically scapular movements are assessed and if they are found to be altered an exercise programme aimed at re-educating the scapular rotator muscles is often undertaken. However, to date there is no empirical research evidence to support the use of this type of exercise programme. Objectives To investigate the effect of a 6 week scapular muscle exercise programme on the muscle activity of lower trapezius, upper trapezius and serratus anterior. Method A test–retest design was used. Subjects were tested at the start, 3 weeks later without any intervention and then 6 weeks later having completed a scapular exercise programme. All subjects were tennis players with signs of shoulder impingement that were confirmed with either or both a positive “empty can” or Hawkins and Kennedy impingement test. Surface electromyography was used to recode the muscle activity of lower trapezius, upper trapezius, serratus anterior and anterior fibres of deltoid. Results During the control period there was no statistical difference in the average muscle activity, variability of the muscle activity and the onset times of lower trapezius, upper trapezius and serratus anterior. Following completion of the exercise programme there was no statistical differences found for the average muscle activity or muscle onset times. The exercise programme statistically reduced the variability of lower trapezius activity but not the other muscles ( p < 0.05 ). Discussion This study suggests that a 6 week scapular exercise programme does alter the muscle activity of lower trapezius and has some potential clinical benefits. Future studies are needed that address the methodological limitations of this study and address if these changes in muscle activity have any clinical significance.

Clinical Presentation of Patients with Tears of the Acetabular Labrum

The clinical presentation of a labral tear of the acetabulum may be variable, and the diagnosis is often delayed. We sought to define the clinical characteristics associated with symptomatic acetabular labral tears by reviewing a group of patients who had an arthroscopically confirmed diagnosis. We retrospectively reviewed the records for sixty-six consecutive patients (sixty-six hips) who had a documented labral tear that had been confirmed with hip arthroscopy. We had prospectively recorded demographic factors, symptoms, physical examination findings, previous treatments, functional limitations, the manner of onset, the duration of symptoms until the diagnosis of the labral tear, other diagnoses offered by health-care providers, and other surgical procedures that these patients had undergone. Radiographic abnormalities and magnetic resonance arthrography findings were also recorded. The study group included forty-seven female patients (71%) and nineteen male patients (29%) with a mean age of thirty-eight years. The initial presentation was insidious in forty patients, was associated with a low-energy acute injury in twenty, and was associated with major trauma in six. Moderate to severe pain was reported by fifty-seven patients (86%), with groin pain predominating (sixty-one patients; 92%). Sixty patients (91%) had activity-related pain (p < 0.0001), and forty-seven patients (71%) had night pain (p = 0.0006). On examination, twenty-six patients (39%) had a limp, twenty-five (38%) had a positive Trendelenburg sign, and sixty-three (95%) had a positive impingement sign. The mean time from the onset of symptoms to the diagnosis of a labral tear was twenty-one months. A mean of 3.3 health-care providers had been seen by the patients prior to the definitive diagnosis. Surgery on another anatomic site had been recommended for eleven patients (17%), and four had undergone an unsuccessful operative procedure prior to the diagnosis of the labral tear. At an average of 16.4 months after hip arthroscopy, fifty-nine patients (89%) reported clinical improvement in comparison with the preoperative status. The clinical presentation of a patient who has a labral tear may vary, and the correct diagnosis may not be considered initially. In young, active patients with a predominant complaint of groin pain with or without a history of trauma, the diagnosis of a labral tear should be suspected and investigated as radiographs and the history may be nonspecific for this diagnosis. Diagnostic Level IV. See Instructions to Authors for a complete description of levels of evidence.

CLINICAL PRESENTATION OF PATIENTS WITH TEARS OF THE ACETABULAR LABRUM

Background: The clinical presentation of a labral tear of the acetabulum may be variable, and the diagnosis is often delayed. We sought to define the clinical characteristics associated with symptomatic acetabular labral tears by reviewing a group of patients who had an arthroscopically confirmed diagnosis. Methods: We retrospectively reviewed the records for sixty-six consecutive patients (sixty-six hips) who had a documented labral tear that had been confirmed with hip arthroscopy. We had prospectively recorded demographic factors, symptoms, physical examination findings, previous treatments, functional limitations, the manner of onset, the duration of symptoms until the diagnosis of the labral tear, other diagnoses offered by health-care providers, and other surgical procedures that these patients had undergone. Radiographic abnormalities and magnetic resonance arthrography findings were also recorded. Results: The study group included forty-seven female patients (71%) and nineteen male patients (29%) with a mean age of thirty-eight years. The initial presentation was insidious in forty patients, was associated with a low-energy acute injury in twenty, and was associated with major trauma in six. Moderate to severe pain was reported by fifty-seven patients (86%), with groin pain predominating (sixty-one patients; 92%). Sixty patients (91%) had activity-related pain (p < 0.0001), and forty-seven patients (71%) had night pain (p = 0.0006). On examination, twenty-six patients (39%) had a limp, twenty-five (38%) had a positive Trendelenburg sign, and sixty-three (95%) had a positive impingement sign. The mean time from the onset of symptoms to the diagnosis of a labral tear was twenty-one months. A mean of 3.3 health-care providers had been seen by the patients prior to the definitive diagnosis. Surgery on another anatomic site had been recommended for eleven patients (17%), and four had undergone an unsuccessful operative procedure prior to the diagnosis of the labral tear. At an average of 16.4 months after hip arthroscopy, fifty-nine patients (89%) reported clinical improvement in comparison with the preoperative status. Conclusions: The clinical presentation of a patient who has a labral tear may vary, and the correct diagnosis may not be considered initially. In young, active patients with a predominant complaint of groin pain with or without a history of trauma, the diagnosis of a labral tear should be suspected and investigated as radiographs and the history may be nonspecific for this diagnosis. Level of Evidence: Diagnostic Level IV. See Instructions to Authors for a complete description of levels of evidence.

The painful hip: new concepts

Hip pain is a common condition, and the work-up often includes imaging. This article reviews the normal MR anatomy of the hip and the imaging findings of internal derangements, snapping hip, and femoral acetabular impingement. We will describe the role of MR arthrography in evaluating the patient with suspected labral and articular cartilage abnormalities, as well as the pitfalls in interpretation. We will review the causes of a snapping hip, and the role of sonography in evaluating and guiding treatment of the snapping iliopsoas tendon. We will also review the radiographic and MRI signs of femoroacetabular impingement (FAI), a cause of early degenerative joint disease and hip pain.

Shoulder Pain in a Collegiate Tennis Player

HISTORY: A 20-year old, left hand dominant, collegiate tennis player presented to his training room for evaluation of left shoulder pain. The shoulder pain had an insidious onset that began while working a summer construction job approximately 2 months prior to presentation. During the summer he had been playing matches and practicing 2–3 hours a day 5–6 days a week. On return to school and tennis playing he had a new racket and increased tension on the strings. He noticed shoulder pain, mostly posterior, during the serve and follow-through. He denied any history of previous shoulder injury or acute event leading up to his current symptoms PHYSICAL EXAM: 20-year old male in no acute distress. Atrophy of the left infraspinatus. Full, pain-free active range of motion. No AC tenderness. Mild tenderness over greater tuberosity of humerus. Pain over greater tuberosity with empty can test. Negative labral, instability or impingement signs. Strength 4-/5 external rotation on left. Remainder of exam normal. DIFFERENTIAL DIAGNOSIS: Suprascapular nerve entrapment Spinoglenoid cyst Suprascapular neuropathy Myopathy TESTS AND RESULTS: Radiology: Plain films – Normal MR I – Atrophy of infra spinatus, Prominent varicosities in suprascapular notch extending medially to a multilobulated cystic abnormality, small area of fibrosis near base of suprascapular notch, tendinosis of infraspinatus and supraspinatus tendons, blunting of posterior labrum, no space occupying lesions in spino-glenoid notch. EMG: Severe, chronic left suprascapular mononeuropathy, single MUAP firing in infraspinatus, 2+ fibrillation potentials in infraspinatus, normal supraspinatus and posterior deltoid FINAL/WORKING DIAGNOSIS: Left suprascapular mononeuropathy restricted to only fibers to infraspinatus TREATMENT AND OUTCOMES: Surgical consult – Conservative treatment recommended Physical therapy – Rotator cuff strengthening and scapular stabilization Active rest for 3 weeks then return to play as tolerated 4. The athlete returned to play after 3 weeks of rest with decreased shoulder pain. Follow-up EMG in 2–3 months

The Accuracy of Subacromial Injections: A Prospective Randomized Magnetic Resonance Imaging Study

To assess the accuracy of shoulder infiltrations in the subacromial bursa (SAB) by a posterior or an anteromedial approach. Magnetic resonance imaging (MRI) and clinical outcome were used for evaluation. A prospective randomized study. Thirty-three patients (22 women, 11 men; average age, 46 years; range, 25 to 64 years) with clinical signs of subacromial impingement were infiltrated with a mixture of bupivacaine, methylprednisolone, and gadolinium-DTPA directly followed by MRI to determine the actual site of injection. The SAB was randomly infiltrated posteriorly (n = 17) or anteromedially (n = 16). Injection confidence of the surgeon and body-mass index of the patient were recorded. Follow-up consisted of the Constant Score, Simple Shoulder Test, and visual analog scale score for pain taken within 24 hours and 6 weeks after infiltration. Thirteen injections (76%) were in the SAB with a posterior approach and 10 (69%) with an anteromedial approach. Many surrounding structures were hit as well, especially the rotator cuff. A positive correlation between the injection confidence of the orthopaedic surgeon and the MRI was found in 66%. Only injection of the SAB alone resulted in a significant decrease of the pain (P = .004) and an increase in the functional scores. Injection in the bursa and rotator cuff muscle showed a significant increase in pain (P = .032) but no change in clinical scores. The body mass index had no influence on the scores. Injections in the SAB are inaccurate, despite the confident feeling of the clinician. The finding that many different structures can be infiltrated with 1 injection can create both false-positive and -negative results. Level II.

Does Neck/Liner Impingement Increase Wear of UHMWPE Liners?

Although impingement damage, backside wear, and damage to the femoral bearing surface are common observations of acetabular liners, they have traditionally been studied independently. In this study, we explore the hypotheses that repetitive impingement increases wear of UHMWPE inserts at both the articular surface and the backside surface, potentially compromising the durability and function of the hip replacement. One hundred thirteen acetabular components were retrieved during revision total hip arthroplasty after an average time in situ of 84 months. Each acetabular liner was examined with incident light and inspected for presence, location, and severity of signs of impingement and backside wear. The depth of penetration of the femoral head into the acetabular liner was also measured to calculate articular wear. Sixty percent (68/113) of acetabular liners examined showed evidence of prosthetic impingement, with moderate or severe damage to the rim in 32% (36/113) of components. Significant backside damage was present in 31% (34/109) of components. Moderate or greater backside wear was found in 61% (22/36) of liners exhibiting significant impingement damage vs 16% (12/73) of liners without impingement (P < .0001). The average wear rate of liners with moderate or severe impingement damage was 0.33 ± 0.07 mm/y, compared with 0.19 ± 0.04 mm/y for liners with mild or no impingement damage (P = .03). Repetitive impingement frequently occurs after THR and leads to a multitude of adverse events, including motion between the liner and the acetabular shell leading to backside wear and accelerated wear of the articular surface.

Supraspinatus tendon US morphology in basketball players: correlation with main pathologic models of secondary impingement syndrome in young overhead athletes. Preliminary report

The purpose of this study was to investigate supraspinatus tendon sonographic morphology in a population of young overhead athletes in correlation with main pathologic models of secondary shoulder impingement syndrome. Between April and May 2004, 20 subjects (ten professional basketball players and ten non-athlete controls of the same age, weight and height ranges) underwent bilateral, standardised, sonographic sholulder examination to evaluate supraspinatus echotexture, supraspinatus and subacromial bursa thickness, subacromial space width (cutoff of 7 mm) and dynamic anterior impingement beneath the acromial margin. All subjects were right handed. No symptomatic controls were found. Four players showed signs and symptoms of right atraumatic shoulder instability (two cases) or supraspinatus impingement with anterior pain (one right and one left shoulder). Subacromial space width was reduced in five right-dominant players' shoulders (three symptomatic and two asymptomatic) versus zero controls (p<0.05) and in eight players' shoulders versus zero controls on total shoulders (p<0.05). No other significant differences were observed between the two groups in sonographic parameters considered. Despite the study limitations, ultrasonography (US) is able to detect subacromial space narrowing in young overhead athletes as early shoulder impingement sign, according to the continuum impingement-instability pathologic model.

In vivo anatomy of the Neer and Hawkins sign positions for shoulder impingement

The Neer and Hawkins impingement signs are commonly used to diagnose subacromial pathology, but the anatomy of these maneuvers has not been well elucidated in vivo. This 3-dimensional open magnetic resonance imaging study characterized shoulder anatomy and rotator cuff impingement in 8 normal volunteers placed in the Neer and Hawkins positions. Subacromial and intraarticular contact of the rotator cuff was graded, and minimum distances were computed between the tendon insertion sites and the glenoid, acromion, and coracoid. Both the Neer and Hawkins maneuvers significantly decreased the distance from the supraspinatus insertion to the acromion and posterior glenoid and from the subscapularis insertion to the anterior glenoid. However, the Hawkins position resulted in significantly greater subacromial space narrowing and subacromial rotator cuff contact than the Neer position. In the Hawkins position, subacromial contact of the supraspinatus and infraspinatus was observed in 7 of 8 and 5 of 8 subjects, respectively. In contrast, rotator cuff contact with the acromion did not occur in any subject in the Neer position. Intraarticular contact of the supraspinatus with the posterosuperior glenoid was observed in all subjects in both positions. Subscapularis contact with the anterior glenoid was also seen in 7 of 8 subjects in the Neer position and in all subjects in the Hawkins position. This extensive intraarticular contact suggests that internal impingement may play a role in the Neer and Hawkins signs.

DIAGNOSTIC ACCURACY OF CLINICAL TESTS FOR THE DIFFERENT DEGREES OF SUBACROMIAL IMPINGEMENT SYNDROME

Background: Several tests for making the diagnosis of rotator cuff disease have been described, but their utility for diagnosing bursitis alone, partial-thickness rotator cuff tears, and full-thickness rotator cuff tears has not been studied. The hypothesis of this study was that the degree of severity of rotator cuff disease affects the diagnostic values of the commonly used clinical tests. Methods: Eight physical examination tests (the Neer impingement sign, Hawkins-Kennedy impingement sign, painful arc sign, supraspinatus muscle strength test, Speed test, cross-body adduction test, drop-arm sign, and infraspinatus muscle strength test) were evaluated to determine their diagnostic values, including likelihood ratios and post-test probabilities, for three degrees of severity in rotator cuff disease: bursitis, partial-thickness rotator cuff tears, and full-thickness rotator cuff tears. A forward stepwise logistic regression analysis was used to determine the best combination of clinical tests for predicting the various grades of impingement syndrome. Results: The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of the eight tests varied considerably. The combination of the Hawkins-Kennedy impingement sign, the painful arc sign, and the infraspinatus muscle test yielded the best post-test probability (95%) for any degree of impingement syndrome. The combination of the painful arc sign, drop-arm sign, and infraspinatus muscle test produced the best post-test probability (91%) for full-thickness rotator cuff tears. Conclusions: The severity of the impingement syndrome affects the diagnostic values of the commonly used clinical tests. The variable accuracy of these tests should be taken into consideration when evaluating patients with symptoms of rotator cuff disease. Level of Evidence: Diagnostic Level I. See Instructions to Authors for a complete description of levels of evidence.