Frozen Shoulder

<中文版>

Frozen shoulder is a condition describing chronic restriction of movement of shoulder and, often, associated with pain.

Definition:

Frozen shoulder is a condition describing chronic restriction of movement of shoulder and, often, associated with pain. Movement restriction is due to adhesive capsulitis of the shoulder joint. Impingement of tendons with or without inflammation causes mild to severe pain.

Symptoms and signs:

Patient often presents with chronic shoulder pain with limitation of movement. Patient may have difficulties in combing, dressing or even feeding. This condition is associated with varying severity of pain, which may interfere with sleeping, or daily activities. The usual age of patient is around fifty and that is why this is well-known as 'Fifty Shoulder' in Chinese.

Examination reveals limitation of movement in all directions, particularly external rotation and internal rotation. The acromio-clavicular joint, glenohumeral joint capsule, and coracoids process are tender. There is muscle weakness. Pain may be referred to the neck and down to the elbow or even forearm and hand.

Cause and biomechanics considerations:

Adhesive capsulitis may be initiated by trivial injury of the rotator cuff tendon(s). Unaccustomed or repetitive movements, such as reaching out for subjects above head or below the cabinet, may impinge and injure these tendons. Without proper medical attention, localized inflammation will cause capsule adhesion, impingement of shoulder movements and mild degree of movement restriction. Patient may try to overcome movement restriction and further traumatized the adhered capsule. This will cause a viscous cycle of injury, inflammation and adhesion.

Clinical Stages:

The "freezing" or painful stage: It may last from six weeks to nine months. Patient may have varying severity of pain and the shoulder gradually loses motion.

The "frozen" or adhesive stage: This stage generally lasts four months to nine months. The shoulder is stiff as suggested by the word “frozen”, but the pain often lessens.

The "thawing" or recovery: Shoulder motions gradually improve. This generally lasts five months to 26 months.

Investigations:

The diagnosis is usually clinical. X-rays are usually normal unless there is coexisting bony fracture, acromial spurs causing the impingement. Muscle tears can be detected by MRI or musculoskeletal ultrasound imaging. The latter is more effective in picking up and in the confirmation impingements dynamically during assessment by a musculoskeletal physician. Musculoskeletal ultrasound can also demonstrate active inflammation, if there is, by using the colour flow mapping.

Treatment:

Treatment depends on symptoms and signs of the patient. The aims are to control symptoms, improve motions, strengthen rotator cuff muscles and return to normal daily activities. Analgesics often are required to control pain especially the night pain at bed time. When there is evidence of ligament or tendon tears, musculoskeletal physicians often offer prolotherapy to trigger tissue repair. Shoulder mobilization after injection is useful to break the adhesions and regain joint motions. Prescribed exercises are indispensible to improve the stability and retrain the weaken muscles. Occasionally, surgery is required to repair cartilaginous injury and joint capsule damages.

五十肩 / 冰凍肩

"五十肩"又稱冰凍肩，指的是肩膀的活動度受到慢性限制，而且通常伴有痛症。

定義:

"五十肩"又稱冰凍肩，指的是肩膀的活動度受到慢性限制，而且通常伴有痛症。肩膀的活動受限主因是病人患上的黏連性肩關節囊炎；而受到夾擠的肌腱則會導致輕微至嚴重的痛症。

症狀與表徵:

病人通常會感到肩關節活動度受限，伴有不同程度的痛症，日常生活受影響，例如梳理、穿衣、餵食可能會有困難，嚴重的時候甚至會影響睡覺。此症多發於五十歲左右的人士，因此中國人俗稱之為"五十肩"。

體檢結果顯示，肩關節活動的所有方向都受到不同程度的限制，特別是外旋和內旋。肩峰鎖骨關節、盂肱關節囊和喙突會出現壓痛，肌肉呈無力感。痛症範圍可以從頸部向下伸延到手肘，甚至前臂及手部。

病因及與生物力學的關係:

肩部旋轉肌腱輕微損傷就可以引起黏連性囊炎。進行一些不習慣或重覆性的動作，例如伸手取物品時提手太高（高於頭頂）或下探得太低（例如櫥櫃的最低格），都可能會傷及這些肌腱。如果沒有適當的治理，局部炎症會引起關節囊黏連、肩關節活動夾擠和輕微的活動受限。病人可能會努力活動受限的關節，因而傷及關節囊，進一步加重肩關節囊的黏連情況。促發受傷、發炎、黏連的惡性循環。

臨床階段:

在疾病的過程中，五十肩大約可分為三個階段：

第一是"啟凍期"或"疼痛期"。此階段可持續 6 星期至 9 個月。病人可能會有不同程度的痛症，肩膀會慢慢喪失活動的功能。

第二是"凍結期"或"黏連期"。一般持續 4 至 9 個月。肩膀感覺僵硬，就好像"凍結"了；但痛症往往有所減輕。

第三是"解凍期"或"康復期"。肩關節的活動度逐步改善。此階段通常持續 5 至 26 個月。

檢驗:

五十肩的診斷通常是臨床的。X光檢驗結果一般都顯示肩關節正常，除非同時有骨折，或有肩峰骨刺引起的肩膀夾擠。磁力共振掃描或肌骼超聲波造影皆可檢測出肌肉撕裂的情況。肌骼科醫生為病人進行評估時，肌骼超聲波造影比起磁力共振掃描可以更有效地檢查及確定肩關節活動時夾擠的情況。肌骼超聲波造影的彩色血流圖像（Colour flow mapping）能顯示出炎症是否有活動性。

治療:

治療方案要視乎病人的症狀和表徵。治療的目的是控制症狀、改善關節活動度、加強肩部旋轉肌羣，並恢復日常的活動。醫生一般會處方止痛劑幫助病人控制痛症，尤其是晚上睡覺時候的痛症。如果韌帶或肌腱有撕裂的情況，肌骼科醫生通常會採取保絡治療（prolotherapy）來促進肌肉組織的修復，治療後的肩關節舒展運動可以幫助鬆解關節的黏連，從而恢復關節的活動度。此外，適當的肩部運動可強化肌肉，改善關節的穩定性。偶爾需動手術，修補損傷的軟骨及關節囊。