Refer patients with clinical findings suggestive of significant rotator cuff rupture (affecting shoulder function) and with normal x-ray findings to specialized care at an early stage.
Patients seeking treatment for shoulder injury who cannot lift their upper arm normally but are not found to have any bone injury relatively often have rotator cuff rupture 34.
Rotator cuff ruptures are rare in people below the age of 40 but in the above circumstances as many as 50% of people over 50 are found to have a rupture.
The annual incidence of rotator cuff ruptures following trauma is estimated at 23-25/100 000 in people aged 40-75 years 3.
It is difficult to distinguish between genuine traumatic ruptures and degenerative ruptures by imaging.
A rupture seen in MRI after a traumatic event may represent
an old rotator cuff rupture that has previously been asymptomatic
a genuine fresh rupture or
a rupture that has become more extensive due to the trauma.
Most degenerative ruptures occur in the area of the supraspinatus tendon.
Symptoms
Symptoms begin suddenly after a traumatic event.
Pain is often the predominant symptom but in significant rotator cuff rupture, there is also shoulder dysfunction.
Typically, normal muscle strength is momentarily lost (pseudoparesis or pseudoparalysis) immediately after shoulder injury. The range of motion tested immediately after trauma may be restricted and muscle strength affected even in the absence of tissue injury.
If there is no structural injury, muscle paresis should resolve within 1-2 weeks.
Shoulder pain after trauma is a highly unspecific symptom (may be due to bruising or strain themselves) and it has not been shown to be correlated with the extent of rotator cuff rupture, for instance.
But a rotator cuff tear typically causes pain, nocturnal aching and a feeling of weakness in the shoulder area.
Workup
Clinical assessment
Patients with shoulder symptoms should always be examined with their upper body naked.
The ranges of active shoulder motion (flexion, abduction, internal and external rotation) should be examined, as well as ranges of passive motion if active motion is restricted.
Examination of a shoulder with symptoms following trauma (after excluding bone, nerve and vascular injuries) should concentrate on testing the strength of rotator cuff muscles.
Testing of rotator cuff muscle strength means testing the strength against resistance, not pain.
The strength of the infraspinatus and supraspinatus muscles (picture 1) should be examined separately (picture 2).
Radiological examination
After shoulder injury, a plain x-ray should be taken to exclude fractures and dislocation (shoulder or AC joint) (picture 3).
An x-ray may sometimes reveal significant pre-existing shoulder osteoarthritis (picture 4) or cuff arthropathy (picture 5); if so, there is no need for further investigations in the early stage.
If traumatic rotator cuff rupture is suspected, MRI should be performed in specialized care, at the latest. It can be used to confirm suspected tendon rupture and assess prognostic factors associated with possible surgery.
Ultrasonography will provide little added value for diagnosis or for choosing the line of treatment. If the decision is made nevertheless to perform ultrasonography due to regional factors or local guidelines, an x-ray should be taken first, anyway.
Treatment and criteria for referral
Symptomatic treatment should be provided immediately after the trauma.
Cold bag, analgesics and encouragement to use the upper limb normally as far as the pain allows
If there is weakness of external rotation or of the subscapular muscle, refer the patient to an orthopaedist.
If no weakness can be detected at first but pain continues and raising of the upper arm may not be normal, the patient should be re-examined in 3-4 weeks.
If pain continues for more than 4 weeks from the trauma but the rotational strength is good, consider the possibility of capsulitis / frozen shoulder, in particular Frozen Shoulder. If there is nothing suggestive of this, refer the patient to an orthopaedist.
Record in the referral any willingness of the patient to have surgery.
Shoulder surgery requires good cooperation and good commitment to treatment after surgery.
Do not hesitate to refer the patient to a physiotherapist to mobilize the shoulder.
If clear changes due to osteoarthritis or cuff arthropathy can be seen on x-ray (pictures 45), treatment is mainly conservative Non-Traumatic Tendon Problems of the Shoulder. If no clear improvement can be seen in (6-)12 months, refer the patient to an orthopaedist for assessment for endoprosthetic surgery.
Surgical treatment
In the case of traumatic rupture, surgical treatment is often considered at an early stage, already, particularly if there is rotational weakness (injured subscapularis and/or infraspinatus, often with supraspinatus).
In small isolated supraspinatus ruptures, conservative treatment can probably be used at first 1. These patients should also be referred for assessment by an orthopaedist because there is no strong evidence available yet regarding the treatment of traumatic rotator cuff ruptures 2.
References
Ranebo MC, Björnsson Hallgren HC, Holmgren T et al. Surgery and physiotherapy were both successful in the treatment of small, acute, traumatic rotator cuff tears: a prospective randomized trial. J Shoulder Elbow Surg 2020;29(3):459-470. [PubMed]
Ryösä A, Kukkonen J, Björnsson Hallgren HC et al. Acute Cuff Tear Repair Trial (ACCURATE): protocol for a multicentre, randomised, placebo-controlled trial on the efficacy of arthroscopic rotator cuff repair. BMJ Open 2019;9(5):e025022. [PubMed]
Aagaard KE, Abu-Zidan F, Lunsjo K. High incidence of acute full-thickness rotator cuff tears. Acta Orthop 2015;86(5):558-62. [PubMed]
Sørensen AK, Bak K, Krarup AL et al. Acute rotator cuff tear: do we miss the early diagnosis? A prospective study showing a high incidence of rotator cuff tears after shoulder trauma. J Shoulder Elbow Surg 2007;16(2):174-80. [PubMed]