Bennett Fracture
Other Names
- 1st metacarpal fracture
- Noncomminuted intra-articular fracture of the base of the proximal first metacarpal
- Bennett’s fracture
- Bennett fracture luxation
- Bennett fracture-dislocation
- Intra-articular two-part fracture of the base of the first metacarpal
- Fracture dislocation of the base of the first metacarpal
- Intra-articular fracture of the first metacarpal base
- Thumb metacarpal base fracture dislocation
- First metacarpal fracture dislocation
- Thumb carpometacarpal fracture dislocation
- Bennett’s thumb fracture
Background
- This page refers to the Bennett fracture, a two part intra-articular fracture of the base of the 1st metacarpal
- Distinct fracture from Rolando Fracture, Epibasal Fracture
History
- Named after Edward Hallaran Bennett (1837-1907), a surgeon from Dublin, Ireland[1]
Epidemiology
- 80% of fractures involve the base of the thumb (need citation)
Introduction
General
- Most common fracture involving base of thumb
- Comminuted, two part intra-articular fracture of base of 1st metacarpal
- Considered unstable, require surgical fixation
Mechanism
- Axial load to a partially flexed thumb
- Resulting in forced abduction of the 1st metacarpal
- Example would be a fist fight/ altercation
- Fracture starts at ulnar base of thumb metacarpal
- Palmar ulnar aspect of thumb is normally stabilized by strong ligaments
- Disruption of the ulnar fragment destabilizes thumb
- Volar fracture fragment remains attached to CMC by volar anterior oblique ligament
- Anterior oblique ligament anchors volar lip of metacarpal to tubercle of the trapezium
- Subsequent, small volar lip fragment remains attached to anterior oblique ligament which is attached to trapezium
- Distal metacarpal fragment contains most of articular surface
- Displaced proximally, radially, dorsally by pull of abductor pollicis longus
- Displaced metacarpal is also rotated in supination by the pull of
- Metacarpal head is also displaced into palm by pull of ADP
Pathoanatomy of the 1st Carpometacarpal Joint
- Joint is formed by articulation
- Unopposed muscles contribute to displacement
Associated Pathology
Risk Factors
- Unknown
Differential Diagnosis
Differential Diagnosis Finger And Hand Pain
- Fractures
- Dislocations
- Tendinopathies
- Extensor Tendon Injuries of the Hand
- Central Slip Extensor Tendon Injury
- Flexor Tendon Injuries of the Hand
- Boutonniere Deformity
- Swan Neck Deformity
- Jersey Finger
- Mallet Finger
- Trigger Finger
- De Quervains Tenosynovitis
- Volar Plate Avulsion Injury
- Sagittal Band Injury
- Mannerfelt Lesion (FPL Rupture)
- Ligament Injuries
- Neuropathies
- Arthropathies
- Nail Bed Injuries
- Pediatric Considerations
- Other
Clinical Features
History
- Patient should be able to describe some kind of trauma or injury
- Pain at the base of thumb
- Worse with movement
Physical Exam: Physical Examination Hand
- Pain at base of thumb
- Inspection: swelling, bruising
- Deformity may or may not be present
- Palpation: Tenderness at base of thumb
- Decreased pinch grasp and grip strength
Evaluation
Radiographs
- Standard Radiographs Hand
- Intra-articular, 2 piece fracture of the base of the 1st metacarpal
- Dorsolaterally displaced
- Small fragment of 1st metacarpal may continue to articulate with trapezium due to attachment ot anterior oblique ligament
- Retraction of the 1st metacarpal shaft by APL
- Robert's View: True AP of thumb
Ultrasound
- 5% sensitivity and 98.3% specificity[7]
- Water bath technique can help
CT
- Useful to clarify complex fracture patterns
Classification
Gedda Classification[8]
- Type 1: single ulnar fragment and subluxation of the metacarpal base
- Type 2: an impaction fracture without subluxation of the first metacarpal
- Type 3 an injury with a small ulnar avulsion fragment in association with metacarpal dislocation
Management
Acute Reduction
- Longitudinal traction on the end of thumb
- In addition to abduction and extension of metacarpal
- Thumb is pronated to bring into opposition with non-displaced palmer fragment
- Pressure at the thumb metacarpal base
Nonoperative
- Indications
- Can be considered in stable, non-displaced fractures
- Immobilization: Thumb Spica Cast
Operative
- Indications
- Most are considered unstable and require surgical intervention
- Unstable fracture patterns
- Intra-articular displacement of >1 mm
- Technique
- ORIF
Rehab and Return to Play
Rehabilitation
- After removal of fixation, emphasis on[11]
- Gradual restoration of thumb and hand range of motion
- Tendon-gliding exercises
- Soft tissue mobilization to prevent adhesions and manage scar tissue
- As symptoms improve, functional training and sports specific conditioning
Return to Play/ Work
- There are no evidenced based guideliness for return to play[12]
- Protocols must be individualized based on healing, function, and sport demands
- Early RTP may involve:[13]
- Protective orthoses, gloves, or taping
- Especially in contact sports, to reduce reinjury risk
Prognosis and Complications
Prognosis
- Radiographic features which predict outcome
- Location, displacement of the fracture
- Extent of crush or impaction at the metacarpal
- Presence or absence of shearing or impaction injury to radial side of articular surface of trapezium
Complications
- High risk of post-traumatic thumb arthritis
- Tendon lacerations and neurovascular injuries are uncommon
- Acute Compartment Syndrome
See Also
Internal
External
- Sports Med Review Hand Pain: https://www.sportsmedreview.com/by-joint/hand/
References
- ↑ CULLINGWORTH, CJ. "JUNE 12, I897. ROYAL MEDICAL AND CHIRURGICAL SOCIETY."
- ↑ 2.0 2.1 Image courtesy of journal.aspetar.com
- ↑ Image courtesy of liftfl.com
- ↑ Carruthers, Katherine H., et al. "Casting and splinting management for hand injuries in the in-season contact sport athlete." Sports Health 9.4 (2017): 364-371.
- ↑ Graham, David J., et al. "Screw and suspension fixation for Bennett Fractures." Journal of Hand Surgery Global Online 5.2 (2023): 206-210.
- ↑ Case courtesy of Mohamed Mahmoud Elthokapy, Radiopaedia.org, rID: 91004
- ↑ Blaivas, Michael, et al. “Water bath evaluation technique for emergency ultrasound of painful superficial structures.” The American journal of emergency medicine 22.7 (2004): 589-593.
- ↑ GEDDA KO. Studies on Bennett's fracture; anatomy, roentgenology, and therapy. Acta Chir Scand Suppl. 1954;193:1-114
- ↑ Graham, David J., et al. "Screw and suspension fixation for Bennett Fractures." Journal of Hand Surgery Global Online 5.2 (2023): 206-210.
- ↑ Image courtesy of schreibermd.com
- ↑ Hardy, Maureen A. "Principles of metacarpal and phalangeal fracture management: a review of rehabilitation concepts." Journal of Orthopaedic & Sports Physical Therapy 34.12 (2004): 781-799.
- ↑ Geldenhuys, A. Grethe, et al. "Return to play protocols for musculoskeletal upper and lower limb injuries in tackle-collision team sports: A systematic review." European journal of sport science 22.11 (2022): 1743-1756.
- ↑ Singletary, Shannon, Alan E. Freeland, and Christopher A. Jarrett. "Metacarpal fractures in athletes: treatment, rehabilitation, and safe early return to play." Journal of Hand Therapy 16.2 (2003): 171-179.