Clinical History:
- 34-year-old falls over during a ski trip
- Mechanism – lands on back of left shoulder with shoulder at high speed
- Felt a mild pop of shoulder but unsure as at high speed
- Able to continue skiing rest of trip but shoulder very painful and restricted range of motion
- Patient didn’t seek medical help whilst broad
- On return from travel 3 weeks later, shoulder pain continues with restricted range
- Difficulty getting dressed and lifting arm above head
- Unable to lie on the left shoulder at nighttime, needing pillows to prop up
- Presents to clinic 4 weeks post injury
Past Medical Hx
Nil
Drug Hx
Nil
Exercise Hx:
- Gym 4-5 times a week with whole body workouts
- Avid skier
- Enjoys playing badminton twice a week (left-handed player)
Examination
Functional testing left shoulder
- Crepitus of the left ACJ on examination
- Pain inhibition for all ranges of the shoulder particularly Forward flexion, Internal and external rotation
- Loss of end range external rotation loss and capsular restriction range of motion inducing pain
- No sulcus sign or sag
- No instability signs on anterior/posterior draw, or relocation testing
Bedside Ultrasound
- Moderate subacromial bursitis and rotator cuff tendinopathy
- No discrete rotator cuff tear.
- ACJ shoulder arthritic change
- Thickening in the inferior axillary recess
- No irregularities in the surgical or anatomical neck of the humerus on ultrasound.
- Small joint effusion in the axillary recess indicates capsular inflammation rather than fracture (note ultrasound cannot rule out bony injury).
Figure 1.
Ultrasound of the axilla and red arrows show the thickness of the inferior axillary recess indicating adhesive capsulitis. The dashed blue arrows indicate a small joint effusion. HH humeral head, SN surgical neck
Differential Diagnosis and clinical reasoning
- Shoulder Fracture
Given the high-velocity nature of the injury, ruling out humeral head, neck or shaft fractures is the first step. This patient did not get any imaging whilst abroad to confirm or refute a fracture. On seeing this patient in clinic, urgent imaging should be requested (beyond bedside ultrasound) to rule out bony injury. X-ray is most cases would be adequate for this.
- Shoulder Capsular Injury and/or Post Traumatic Capsulitis
Blunt force on the glenohumeral joint (GHJ) in a Posterior to Anterior direction leaves the shoulder vulnerable for dislocation. In this case, although there was no clear history of a shoulder dislocation requiring self and medical relocation, this does not rule out momentary subluxation or capsule disruption. The patient is now presenting with a capsular restriction pattern on examination and further evidenced by the fluid in the axillary recess on ultrasound (indicating adhesive capsulitis).
- Rotator cuff injury
Blunt trauma and a compression mechanism to the shoulder makes rotator cuff injury in comparison to other mechanisms where the arm is away from the body (e.g. overreaching, throwing and stretching). At this stage, 3 weeks after the injury, there is likely to be some reactive rotator cuff and subacromial inflammation, but this is unlikely to be the primary injury or pain driver. Furthermore, bedside ultrasound evaluation rules out any significant rotator cuff tears to explain the pain level (the subacromial bursitis is likely to be reactive).
- ACJ Joint Injury
This is very likely given the injury mechanism. A bad ACJ sprain can leave patients debilitated with marked pain inhibition. However, on closer examination, ACJ pain is unlikely to explain the end range loss external rotation due to capsular restriction. ACJ injury may be a secondary cause of pain in this case.
Further Imaging
An urgent MRI was arranged within 48 hours.
MRI
Posterior humeral head bone bruising and Hill Sachs lesion indicating previous trauma and history of anterior shoulder dislocation. Anterior capsule rupture, scarring and joint effusion. No GHJ or labral damage.
Diagnosis
Glenohumeral joint dislocation with Hill Sachs lesion, anterior capsular disruption and traumatic adhesive capsulitis.
Management
- The patient’s pain and lack of shoulder range of motion is likely to be due to the reactive capsulitis.
- Gentle range of motion was encouraged as well as shoulder girdle and rotator cuff strengthening routines.
- At 8 weeks, the patient was still suffering from pain inhibition, global restriction of range of motion and night pain
- A hydrodistension was performed to release the shoulder capsule which greatly improved range and facilitated rehabilitation.
Hydrodistension for Frozen Shoulder
This video shows a shoulder hydrodistension for frozen shoulder. Fluid is being pushed into the glenohumeral joint capsule to release the joint.
- At 12 weeks post injury patient moved on to higher level shoulder proprioception and stability training
- Return to overhead sports at 15 weeks post injury without any shoulder instability symptoms
Discussion And Key Points
- When assessing shoulder injuries, the mechanism is likely to indicate whether the underlying pathology is bony, tendon, labral or capsular.
- For traumatic shoulder injuries e.g. during skiing always consider the possibility of fracture and bone bruising. Most fractures occur around the greater tuberosity. Remember that fractures around the anatomical neck of the humerus can have neurovascular implications for the whole arm. It is important to order the appropriate investigation in a timely manner (mainly X-ray and/or MRI).
- Most shoulder dislocations occur in an anterior direction. Posterior dislocations occur when there is an anterior to posterior force on the GHJ, e.g. epileptic seizure, car accident, skiing. A detailed mechanism of injury history and examination is therefore required to help rule this out.
- Labral tears are not always associated with shoulder dislocations. However, if they are detected, special consideration is required to detect and manage shoulder instability symptoms.
- In patients under the age of 40, the most common cause of adhesive capsulitis is traumatic. This can come on weeks after the initial injury and persist for many months.
- Medical intervention such as ultrasound guided injections should be considered to help expedite rehabilitation and improve patient function and pain.
