Acromioclavicular Osteoarthritis Research Articles

Motion of the shoulder complex in individuals with isolated acromioclavicular osteoarthritis and associated with rotator cuff dysfunction: Part 1 – Three-dimensional shoulder kinematics

This study described the three-dimensional shoulder motion during the arm elevation in individuals with isolated acromioclavicular osteoarthritis (ACO) and ACO associated with rotator cuff disease (RCD), as compared to controls. Seventy-four participants (ACO=23, ACO+RCD=25, Controls=26) took part of this study. Disability was assessed with the DASH, three-dimensional kinematics were collected during arm elevation in the sagittal and scapular planes, and pain was assessed with the 11-point numeric pain rating scale. For each kinematic variable and demographic variables, separate linear mixed-model 2-way ANOVAs were performed to compare groups. Both ACO groups had higher DASH and pain scores. At the scapulothoracic joint, the isolated ACO group had greater internal rotation than control, and the ACO+RCD group had greater upward rotation than both other groups. At the sternoclavicular joint, both groups with ACO had less retraction, and the isolated ACO group had less elevation and posterior rotation. At the acromioclavicular joint, the isolated ACO group had greater upward rotation, and both ACO groups had greater posterior tilting. Patients with ACO had altered shoulder kinematics, which may represent compensatory responses to reduce pain and facilitate arm motion during arm elevation and lowering.

Degenerative Joint Disease of the Acromioclavicular Joint

Osteoarthritis of the acromioclavicular (AC) joint is a common condition causing anterior or superior shoulder pain, especially with overhead and cross-body activities. This most commonly occurs in middle-aged individuals because of degeneration to the fibrocartilaginous disk that cushions the articulations. Diagnosis relies on history, physical examination, imaging, and diagnostic local anesthetic injection. Diagnosis can be challenging given the lack of specificity with positive physical examination findings and the variable nature of AC joint pain. Of note, symptomatic AC osteoarthritis must be differentiated from instability and subtle instability, which may have similar symptoms. Although plain radiographs can reveal degeneration, diagnosis cannot be based on this alone because similar radiographic findings can be seen in asymptomatic individuals. Nonoperative therapy can provide symptomatic relief, whereas patients with persistent symptoms can be considered for resection arthroplasty by open or arthroscopic technique. Both techniques have proven to provide predictable pain relief; however, each has its own unique set of potential complications that may be minimized with an improved understanding of the anatomical and biomechanical characteristics of the joint along with meticulous surgical technique.

Arthroscopic Decompression with Acromioplasty and Structured Exercise Was No More Effective and Was More Expensive Than Exercise Alone

Question: In patients with shoulder impingement syndrome, what is the effectiveness and cost-effectiveness of arthroscopic decompression with acromioplasty and structured exercise compared with structured exercise alone? Design: Randomized (allocation concealed), blinded (outcome assessor) controlled trial with 2-year follow-up. Setting: 2 hospitals in Finland. Patients: 140 patients (18 to 60 years ofage; mean age, 47 y; 63% women) who had suspected shoulder impingement syndrome. Inclusion criteria were a positive Neer test; shoulder pain resistant to rest, anti-inflammatory drugs, subacromial glucocorticosteroid injections, and physiotherapy; and symptoms persisting for 3 months. Exclusion criteria were glenohumeral or acromioclavicular osteoarthritis, signs of glenohumeral instability, previous surgery to the affected shoulder, full-thickness tear of the rotator cuff, cervical radicular syndrome, adhesive capsulitis, or neuropathy of the shoulder area. End-point data were available for 134 patients (96%). Intervention: Patients were allocated to combined surgery plus structured exercise (n = 70) or exercise alone (n = 70). The structured exercise program consisted of an individually tailored home-exercise regimen that aimed to restore painless and normal mobility of the shoulder complex and increase the dynamic stability of the glenohumeral joint and scapula. Training involved the use of stretch bands and light weights. Sessions were held 4 times per week with use of 9 different exercises with 30 to 40 repetitions 3 times. As ability and strength improved, the resistance was increased and the repetitions were decreased. During arthroscopic decompression, the arthroscope was introduced through a standard posterior portal and debridement and decompression were done by shaver or vaporizer. Acromioplasty was performed with a burr drill, starting anteriorly and progressing posterolaterally. 7 to 10 days after surgery, sutures and dressings were removed and patients received the same individually tailored exercise program as provided to the exercise-alone group. Main outcome measures: The primary outcome was self-reported pain on a visual analog scale (VAS) of 0 to 10 (0 = no pain, 10 = maximum imaginable pain; 1.5 was the minimal clinically important difference). Secondary outcomes were disability, pain at night, working ability, shoulder questionnaire score, number of painful days in the previous 3 months, and the proportion of pain-free patients (VAS ≤3). Costs were in 2004 prices (€) and included direct healthcare (operation, hospitalization) and non-healthcare (travel, massage, manipulation) resources. Main results: Analysis was by intention to treat. The study had sufficient power to detect at least a 1.5-unit difference in self-reported pain between combined treatment and exercise. A decrease in self-reported pain exceeding the minimal clinically important difference occurred in both the combined treatment and exercise-alone groups. Between-group differences were not significant (Table). The groups were not different for any of the secondary outcomes. The mean total cost was €2961 in the combined treatment group and €1864 in the exercise group (mean incremental cost €1097). The incremental cost-effectiveness ratio was €5431 per minimal clinically important difference unit With a willingness to pay of €8000 for 1 additional minimal clinically important difference unit, the probability that combined treatment would be acceptable was 56%.

Sonography of the painful shoulder: role of the operator’s experience

The aim of our study was to determine the role of the operator's experience in the sonographic evaluation of the painful shoulder and to validate assumptions about its technical performance in routine practice. Two radiologists, respectively standard and expert sonographic operators, independently and prospectively scanned 65 patients with clinical suspicion of rotator cuff lesion. Magnetic resonance arthrography was the reference standard. The sensitivity of the expert ultrasound operator was 95.3% for full-thickness rotator cuff tears (41/43), 70.6% for partial-thickness tears (12/17), 64.3% for intratendinous tears (9/14), 100% for abnormality of the long head of biceps tendon (seven of seven), 88.9% for supraspinatus tendinosis (16/18), 96.4% for subacromial bursa abnormalities (53/55), and 91.7% for acromioclavicular joint osteoarthritis (33/36). The two sonographic operators were in very good agreement about full-thickness rotator cuff tears (kappa = 0.90), supraspinatus tendinosis (kappa = 0.80), abnormalities of the long head of biceps tendon (kappa = 0.84), subacromial bursa abnormalities (kappa = 0.89), and acromioclavicular osteoarthritis (kappa = 0.81). The agreement was only moderate for partial-thickness tears (kappa = 0.63) and intratendinous tears (kappa = 0.57). Our results show that in moderately experienced hands as in experts' hands, sonography has a low level of interobserver variability for full-thickness rotator cuff tears. Considering partial-thickness and intratendinous rotator cuff tears, our data suggest that interobserver variability is higher.

Acromioplasty, Distal Clavicle Resection and Rotator Cuff Repair in Elderly Patients with Rotator Cuff Tear and Acromioclavicular Osteoarthritis

Objectives: To present the surgical results on a specific, selected group of sixteen elderly patients (average age: 65.6 years) who had both rotator cuff tear and acromioclavicular joint osteoarthritis. Methods: Three procedures were carried out through a single anterior incision. Acromioplasty was done first, followed by distal clavicle resection and the rotator cuff repair was performed last. A modified UCLA shoulder scoring system and a L' Insalata self-administered questionnaire were used to assess the surgical results. Results: The patients were followed up for an average of 44.1 months. The modified UCLA score improved from 14.5±3.44 to 32.81±2.04 (p＜0.001). The overall and each of the domain scores in the L' Insalata self-administered questionnaire showed significant improvement. Conclusions: This combination of three procedures through a single anterior skin incision is an effective surgical method in the treatment of patients who have been affected with both rotator cuff tear and acromioclavicular joint osteoarthritis.

Ultrastructure of the subacromial bursa in painful shoulder syndromes.

In order to determine if inflammation of the subacromial bursa or "bursitis" is as common an occurrence as believed in painful conditions of the shoulder, eight bursae were obtained during surgery from 3 cases of calcifying tendinitis, 2 of tight coracoacromial ligament, 2 of rotator cuff tear and 1 of acromioclavicular osteoarthritis. In the cases of calcifying tendinitis, tight coracoacronial ligament and rotator cuff tear the morphological changes mainly consisted of a numerical increase in cells throughout the bursal wall along with proliferation of endothelial cells in the vascular channels. All of the cells including the endothelial had densely packed, intermediate type filaments in their cytoplasm but no appreciable diminution of metabolic organelles. Lipid droplets were abundant in the extracellular connective tissue of the bursae from the cases with rotator cuff tear. In contrast to the other cases, the bursa from the case of acromioclavicular osteoarthritis showed widespread fibrin deposition in association with cell necrosis. In none of the cases did inflammatory leukocytic cells infiltrate bursal tissue. We conclude, that the subacromial bursa tends to undergo proliferative or degenerative changes in rotator cuff tendinopathies but bursal inflammation with polymorphonuclear cell infiltrate does not occur commonly.