Incidence
- 3-5% of fractures of shoulder girdle
- most common scapular fractures in order
- body
- neck 60%
- glenoid 10%
- acromion
- Bimodal
- based on the vector and mechanism of force to the shoulder.
- Low energy / sports related
- partial articular fractures
- usually involve the anterior glenoid process
- commonly associated with anterior shoulder dislocations (bony Bankart lesions)
- high-energy trauma
- glenoid neck and body,
- may or may not involve the glenoid articular surface.
- beware associated injuries
- diagnosis and subsequent treatment of a scapula fracture are often delayed due to treatment of other life-threatening or limb-threatening conditions
- partial articular fractures
- Low energy / sports related
- based on the vector and mechanism of force to the shoulder.
Associated Injuries
- seen in upto 80-90% of patients
- pulmonary injuries & pneumothorax (23%)
- clavicle fractures (23%), which represents floating shoulder injury
- shoulder dislocation either anterior or posterior
- brachial plexus injuries
- rib fractures
- flail chest/tension pneumothorax
- vascular injuries
Classification
According to Anatomical Region
| Type | Description |
|---|---|
| Type I | Apophyseal fractures |
| IA | Acromion process |
| IB | Scapular spine |
| IC | Coracoid process |
| Type II | Glenoid neck fractures |
| IIA | Vertical, lateral to base of spine |
| IIB | Vertical, involving base of spine |
| IIC | Transverse fracture |
| Type III | Fracture of glenoid articular surface |
| Type IV | Fracture of the scapular body |
Scapular Neck
| Type | Description |
|---|---|
| I | nonangulated, nondisplaced |
| IIA | shortened / displaced > 1 cm |
| IIIB | Angulated > 40 deg |
Glenoid Lip
Glenoid Fossa
| Type | Description |
|---|---|
| I | Anterior avulsion fractures |
| II | Transverse, inferior glenoid |
| III | Transverse, superior glenoid |
| IV | Transverse, through body |
| V | Combo of types II & IV |
Pathology
- body
- neck
- usually these fractures are impacted & extra-articular
- glenoid lip
- usually involve either anterior or posterior lip of glenoid & are oriented vertically (& exit inferiorly)
- large lip fractures of glenoid are usually associated with subluxation or partial dislocation of head of humerus
- glenoid fossa
- typically present with transverse fracture thru glenoid
- some fractures will extend medially across scapula & exit just medial tocoracoid or will exit at medial aspect of scapula
Investigations
Xrays
- AP of Shoulder
- essential to rule out articular involvement with high quality AP view in which there is no overlap of humerus over glenoid
- ideally, view should be purely tangential to glenoid
- 45 deg cephalic tilt allows evaluation of coracoid fractures
- Apical Oblique View
CT scanning
- particulary helpful in evaluation of intra articular glenoid fractures
- allows more accurate assesment of articular step off, as well as displacement & angulation of glenoid neck
- Systematic Review
- need to carefully assess entire scapular body & spine, acromion, coracoid, & glenoid
- need to asses each articulation: glenohumeral, AC joint, & scapulo-thoracic
Treatment
Nonoperative
- vast majority of scapula fractures may be treated non operatively
- closed reduction of these fractures is usually not possible
- treatment consists of support of sling & early motion
- most fractures will heal by 6 weeks
Operative
Indications
- Body
- rare
- Neck
- Controversial
- > 10mm medial displacement
- > 40 deg angulation
- Medialization of glenoid up to 1cm is well tolerated by most patients
- Controversial
- Glenoid Rim
- > 10 mm displacement
- > 25% of joint surface & displaced
- (due to likelihood of instability)
- Glenoid fossa
- subluxation & instability of humeral head
- stop off of 3-4mm
- > 20% of joint involved
- but dependent on patient’s occupation, age, activity level, physiologic status, and hand dominance.
- Acromion
- depressed acromion fractures that encroach on subacromial space & interfere with rotator cuff function
Surgical Approach
- anterior rim fractures are approached anteriorly & posterior rim fractures are approach posteriorly
- transverse glenoid fractures may be directly reduced through anterior approach & have fixation via percutaneously inserted screws from above (thru deltoid)
- Anterior Approach in Fractures of Glenoid
- for fractures of anterior & inferior margins of glenoid, deltopectoral approach may be chosen
- reduction of inferior glenoid fractures can be difficult due to proximity of axillary nerve
- osteotomy of coracoid may be necessary for improved exposure
- reattach coracoid with 4.5 mm cortex screw & absorbable washer to avoid splitting of coracoid tip
- Implants:
- 3.5mm cortex screws or 4.0mm cancellous screws as lag screws
- 1/3 tubular plate may be applied below glenoid to lateral border of scapula as butress
Extra-articular Scapular Fractures
- Treatment Considerations
- with glenoid neck fractures, (articular surface in intact) fractures extends from suprascpular notch area across neck to lateral border of scapula
- glenoid neck fractures is often displaced but intact clavicle & AC joint will limit displacement & provide stability
- implant of choice is often contoured 3.5 pelvic reconstruction plate which is applied to posterior border of glenoid & lateral
- border of scapula
- Implants
- 1/3 tubular plate, 3.5 mm DCP, or LC-DCP for fixation of Clavicle
- 3.5 mm DCP or LC-DCP
- contoured 3.5 pelvic reconstruction plate
- 4.0 mm cancellous bone screws as lag screws
Prognosis
- body
- good prognosis for healing
- neck
- good prognosis for healing
- if “operative scapular fractures” is treated non operatively
- patient may develop abductor weakness & subacromial impingement
- outcomes:
- Scapular neck fracture influence of permanent malalignment of glenoid neck on clinical outcome
- J. Romero. Archives of Orthopaedic & Trauma Surgery. 1434-3916 Volume 121 Issue 6 (2001) pp 313-316
- authors analyzed effect of associated shoulder girdle injury on glenoid displacement & influence of glenoid malalignment on clinical outcome
- 19 patients with scapular neck fractures were reviewed clinically & radiologically at mean of 8 years after injury
- none of them has developed nonunion of scapular neck, & only one showed radiological signs of mild degenerative joint disease
- glenopolar angle (GPA), which assesses rotational malalignment of glenoid about anteroposterior
- axis perpendicular to scapular plane on plain X-rays was measured less than 20° in six patients
- 3 of them had sustained associated clavicular fracture or AC joint dislocation
- other 3 patients had permanent severe malalignment of glenoid neck in absence of associated shoulder girdle injury
- 5 patients with GPA less than 20° complained of moderate or severe pain
- 13 patients with mild or no glenoid rotational displacement or medial displacement alone
- 11 patients had no or mild pain, & only 2 had moderate or severe pain
- 5 patients presented with reduced activities of daily living, 4 of them had severe glenoid rotational displacement
- loss of motion was found in only 2 patients, & both had severely displaced glenoid neck