Schulterinfo.ch - Glenohumeral Joint - Frozen Shoulder - Capsulitis
Schulterinfo.ch
Abstract
Also called adhesive capsulitis or pericapsulitis, frozen shoulder describes a functional restriction of movement in all three dimensions of the glenohumeral joint, which presents itself during passive as well as during active motions. Patients also experience pain as the symptoms are a result of capsular fibrosis following a synovial inflammation. Women are generally more affected and prevalence is highest between 40 and 60 years of age.
Diagnosis is made in regards to clinical course as well as examination of the patient.
Frozen shoulder is a common and often overlooked diagnosis in patients with e.g. diabetes.
With little movement, the shoulder joint capsule and surrounding structures contract, making the range of motion physically restricted in addition to being painful. In Ultrasound diagnostics, the diagnosis can be made very precisely and at an early stage regardless of the stage. Arthrography shows decreased volume of the joint capsule. It is rarely seen before age 40.
The process typically has three phases, Phase I: increasing pain and stiffness for 2 to 9 months, Phase II: substantial stiffness but less pain for 4 to 12 months, Phase III: pain resolves, and function is gradually restored over 5 to 26 months
Treatment consists of NSAIDs, supervised physical therapy, and of intraarticular corticosteroid injections. Physical therapy should be avoided as much as possible in the early inflammatory phases. In the later phases of the disease, physiotherapy can alleviate the restriction of movement to some extent. Viscosupplementation or high volume injections has been reported to be beneficial. Rarely surgical intervention is necessary.
Frozen shoulder describes a functional restriction of movement in all three dimensions of the glenohumeral joint, which presents itself during passive as well as during active motions. Patients also experience pain as the symptoms are a result of capsular fibrosis following a synovial inflammation.
The exact pathogenesis is not understood as yet. However, literature agrees that inflammation leads to changes of the glenohumeral joint, resulting in a fibrosis and contracture of the capsule [1]. On biopsy, these changes become clearer as chronic inflammatory cells and proliferating fibroblasts can be observed [2]. Some of those fibroblasts were also found to transform to myofibroblasts, creating collagen in form of thick bands, which were ultimately accredited with the contracture of the joint capsule [3]. Adherence to the anatomical neck of the humerus may then cause pain when abruptly stretched [4]. Additionally, increased levels of inflammatory cytokines were found in the synovial lining and are thought to be responsible for early inflammatory processes [2]. Yet, it is unknown, what initiates these processes.
Generally, adhesive capsulitis can be divided in two different groups according to the Lundberg definition:
- Primary (idiopathic)
- Secondary
- Diabetes mellitus
- Post-traumatic (e.g. after fracture of the proximal humerus)
- Post-surgery (e.g. repair of rotator cuff tear)
- Inflammatory arthritis
- Hyperthyroidism
More women than men are affected by the idiopathic form of frozen shoulder with a high prevalence in patients aged between 40 and 60 years [1]. The prevalence of adhesive capsulitis amounts to 2% to 5% [2, 3] and is more often seen in the nondominant shoulder [2, 4]. Moreover, several studies have shown that patients with type 2 diabetes mellitus are up to 5 times more likely to develop a frozen shoulder than the general population as prevalence in patients suffering from the disease is estimated at 13.4% [2, 3].
Patients suffering from adhesive capsulitis generally present with a more gradual onset of pain than in other similar shoulder pathologies [1-4]. Pain is also often referred to the insertion of the deltoid muscle [4]. However, pain is rarely associated with repetitive overhead activity, which is suggestive of other conditions [4]. As adhesive capsulitis progresses, both passive and active range of motion of the affected shoulder gradually decrease [2, 4]
Overall, the course of disease in frozen shoulder can be divided in three different stages:
- Phase one, 10-36 weeks (freezing phase)
- Patients complain about progressive pain, mostly during night-time and beginning stiffness in the shoulder area (glenohumeral joint). Patients are unable to sleep on the affected shoulder. In the beginning, symptoms are often associated with trivial injuries such as a bruise or strain [1].
- Phase two, 4–12 months (frozen phase)
- The stiffness increases, especially during abduction or external rotation as the pain gradually ameliorates.
- Phase three, 5-26 months (thawing phase)
- The symptoms improve progressively until in most cases shoulder functionality has recovered completely
In secondary adhesive capsulitis phases might not be as distinct. Additionally, remission rates are also lower, which might indicate other therapy options [1].
- Begin of symptoms
- Triggering factors
- Underlying disease, previous trauma or surgery
- Pain qualities
- Night pain and sleeping on affected shoulder results in pain
- Painful elevation and external rotation
- Radiating pain in fingers
- Long duration can result in a manifestation of pain around the medial scapula (increased compensatory scapular movements)
- Associated comorbidities
- Diabetes
- Conditions of the thyroid
- Neurological conditions
- Heart disease
Priority in diagnosing frozen shoulder is the clinical examination of the patient. Documentation of the range of motion (neutral zero method) can be of avail to visualize trends and therapy success. As the onset is very subtle, patients tend to wait to see a physician, attributing the symptoms to a simple bruise or strain. Therefore, patients often present in phase II or III [3]. Palpation generally does not reveal any specific point of tenderness [4].
Examination should include:
- Testing of global shoulder function
- Testing of shoulder function while fixating scapula
- Limited passive external rotation with firm endpoint and limited passive abduction with firm endpoint are very characteristic for adhesive capsulitis [5]
Only a firm and reproducible endpoint is proof of an anatomical restriction, whereas a soft endpoint rather suggests limitations of motions due to pain or muscular anomalies. An intraarticular lidocaine injection can therefore be indicated to differentiate between the two types of endpoints [1].
If frozen shoulder is clinically suspected, the radiograph is usually not indicative. Radiographic imaging is primarily used to exclude other shoulder pathologies associated with stiffness and pain [1, 4]. However, there are certain radiographic changes, which are suggestive of adhesive capsulitis such as:
- MRI
- Subcoracoid triangle sign (obliteration of subcoracoid fat)
- Fibrosis of posterior recessus
- Thickening of the coracohumeral ligament (CHL) and joint capsule
- Ultrasound
- Paracoracoid fat pad inflammation
- Synovitis in the rotator interval and glenohumeral joint
- Thickening of the coracohumeral ligament
- Synovial adhesions
- Bursitis
- In the later stages of the disease, erosions at the point of insertion of the joint capsule posteriorly, inferiorly, and anteriorly are typical [7].
- X-Ray
- No clinically relevant findings
- Osteopenia of the proximal humerus can be found
- Excluding of differential diagnosis
- MRI
- Calcific tendinitis
- Osteoarthritis
- Inflammatory arthritis
- Subacromial Impingement
- Enthesitis
Since spontaneous remission is high, conservative treatment takes a central role in dealing with frozen shoulder. For example, if an underlying diabetic disease is present, the optimal treatment of the endocrinopathy should be sought.
The goal of therapy is reducing pain and increasing quality of life as well as improving shoulder functionality. In case of resistance to therapy (>6 months), more invasive methods should be considered. Data from several studies also suggests that conservative treatment is especially effective in phase one and beginning of phase two (acute-inflammatory) whereas patients profit from invasive procedures mostly if stiffness prevails over a longer period of time [6]. Anti-inflammatory treatments are very efficient and safe to use, especially in the early inflammatory phase.
A selection of several treatment modalities can be found hereafter:
- Conservative treatment
- Oral NSAID and corticosteroids
- Intraarticular steroid injections
- Physiotherapy with mobilization (Do not consider in the 1st and 2nd inflammatory phase.)
- Calcitonin (Unfortunately no longer available)
- Hydrodistension
- Hyaluronic acid injections
- High dose vitamin C
- Invasive treatment
- Closed manipulation under anaesthesia (we strongly advise against this treatment, as iatrogenic damage can be caused, especially in areas of the labrum.)
- Arthroscopic arthrolysis (360° Capsulotomy)
Patients especially benefit from early intraarticular corticosteroid injections and physical therapy, resulting in better short and long-term follow-ups [1-3]. It is usually recommended to inject a 40mg dose of triamcinolone or methylprednisolone [2]. Additionally, long-acting local anaesthetics with the application of a high volume may be administered to achieve immediate pain relief [2]. Moreover, NSAID and oral corticosteroids may be helpful in relieving pain throughout the course of the disease. Other treatments listed above may act supplementary for pain control and improvement of ROM [3]. Surgery is only performed during phase two, as inflammation has mostly subsided by then. When needing to choose between invasive treatments, arthroscopic arthrolysis is highly recommended, although similar outcomes have been reported [1]. Yet, iatrogenic injuries (e.g., rotator cuff tears) are much more prevalent in closed manipulations [1, 3]
Prognosis and progressive course of disease
The duration of the disease with or without treatment varies between 1 and 4 years, but typically lasts 18 to 24 months [2]. It should be noted that a longer freezing phase most often results in a longer thawing phase as well. Complete remission can be expected in most patients after conservative treatment [3]. Prognosis and results after surgery are generally worse in patients with diabetes [2, 4]. Despite being a primarily benign condition, there are cases in which limitations in range of motion remain. Patients are suffering from prolonged limited range of motion, especially external rotation, after undergoing the three phases have been reported in up to 15% [2]. However, quality of life is rarely affected mainly because most patients are low demand.
- Wieser K., Bouaicha S., 2020. Die «Frozen shoulder» – Eine häufig verpasste Diagnose der Schulterchirurgie! Rheuma Schweiz Fachzeitschrift 2020; 12. Jahrgang, Nr. 2, pp.10-14
- Fields, Brandon K. K., Matthew R. Skalski, Dakshesh B. Patel, Eric A. White, Anderanik Tomasian, Jordan S. Gross, and George R. Matcuk. 2019. "Adhesive Capsulitis: Review Of Imaging Findings, Pathophysiology, Clinical Presentation, And Treatment Options". Skeletal Radiology 48 (8): 1171-1184. doi:10.1007/s00256-018-3139-6.
- Redler, Lauren H., and Elizabeth R. Dennis. 2019. "Treatment Of Adhesive Capsulitis Of The Shoulder". Journal Of The American Academy Of Orthopaedic Surgeons 27 (12): e544-e554. doi:10.5435/jaaos-d-17-00606.
- Neviaser, Andrew S., and Robert J. Neviaser. 2011. "Adhesive Capsulitis Of The Shoulder". American Academy Of Orthopaedic Surgeon 19 (9): 536-542. doi:10.5435/00124635-201109000-00004.
- Robinson, C., Seah, K., Chee, Y., Hindle, P. and Murray, I., 2012. Frozen shoulder. The Journal of Bone and Joint Surgery. British volume, 94-B(1), pp.1-9.
- Challoumas D, Biddle M, McLean M, Millar NL. Comparison of Treatments for Frozen Shoulder: A Systematic Review and Meta-analysis. JAMA Netw Open. 2020;3(12):e2029581. Published 2020 Dec 1. doi:10.1001/jamanetworkopen.2020.29581
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Frozen Shoulder Treatment at Nirschl Orthopaedic Center in Arlington