Capitellum Fracture
Other Names
- Elbow Fracture
- Capitellum fractures
- Capitellar Fracture
Background
- This page refers to a fracture of the articular part of the distal Humerus, known as the Capitellum
History
- First case published by Han 1853 (need citation)
Epidemiology
- Uncommon/ rare elbow fracture
- Represents 1% of all elbow fractures[1]
- 4-6% of all distal humerus fractures[2]
- More common in females (need citation)
Introduction
General
- Rare but potentially devasting fracture of the elbow
- Almost universally occur in skeletally mature individuals
- Diagnosis is made radiographically
- The vast majority of cases require surgical fixation
Etiology
- Typically involves fall on outstretched hand, often from standing
- Elbow is semi-flexed
- Axial transmitted to capitellum by the radial head
- Affects the Radiocapitallar Joint
Pathoanatomy
- Capitellum fractures often involve[6]
- Trochlea’s anterior aspect
- Lateral epicondyle
- Lateral column’s posterior aspect
- Occasionally involve the posterior trochlea and medial epicondyle
Associated Conditions
Anatomy of the Capitellum
- Convex and rounded projection that articulates with the head of the radius
- Forms the radiocapitellar joint, part of the elbow joint proper
- Covers the anterior, inferior surfaces of the lateral condyle of the humerus
- Extension: inferior surface in contact with humerus
- Flexion: radial head slides towards anterior aspect humerus
Risk Factors
- Unknown
Differential Diagnosis
Differential Diagnosis Elbow Pain
- Fractures
- Adult
- Pediatric
- Dislocations & Instability
- Tendinopathies
- Bursopathies
- Ligament Injuries
- Neuropathies
- Arthropathies
- Other
- Pediatric Considerations
- Little League Elbow
- Panners Disease (Avascular Necrosis of the Capitellum)
- Nursemaids Elbow (Radial Head Subluxation)
Clinical Features
History
- History of trauma
- Patient self reports pain, swelling, deformity especially along lateral aspect of elbow
- Inability to fully extend or flex the elbow
Physical: Physical Exam Forearm
- Ecchymosis, swelling
- Tenderness
- Loss of range of motion/ mechanical symptoms
- Pain on pronation/supination
Evaluation
Radiographs
- Standard Radiographs Elbow
- Best viewed laterally
- May be missed if fracture fragment is small
- Osteochondral lesions may be missed if fragment is occult
- McKee's 'double arc sign' two seperately visible arcs represent displaced capitellum, trochlea[9]
- Radial head-capitellum view can facilitate definition of the fracture fragment
CT
- Can be helpful to clarify fracture pattern, classification
Classification
Bryan and Morrey Classification (with McKee modification)
- Type I: Large osseous piece of the capitellum involved in coronal plane, may involve trochlea
- Type II: Kocher-Lorenz fracture, shear fracture of articular cartilage, articular cartilage separation with very little subchondral bone attached
- Type III: Broberg-Morrey fracture, severe comminution
- Type IV: McKee modification, coronal shear fracture that includes the capitellum and trochlea
Management
Nonoperative
- Indications
- Nondisplaced type I, II with <2 mm displacement
- Splint: Posterior Long Arm Splint for 2-3 weeks
- Transition to pre-fab for early range of motion exercises
- These patients require careful monitoring to ensure maintenance of reduction
Operative
- Indications
- Displaced type I, II, III fractures >2 mm
- Type IV fractures
- Technique
- ORIF (can be open or arthroscopic)
- Fragment excision
- Arthroplasty
Rehab and Return to Play
Rehabilitation
- Highly variable
- Discretion of orthopedic surgeon
Return to Play/ Work
- Needs to be updated
Prognosis and Complications
Prognosis
- Untreated displaced capitellum fracture uniformly leads to a poor functional outcome
Complications
- Persistent Elbow Pain
- One of the most common complications[10]
- Elbow contracture
- Nonunion
- Ulnar Nerve Injury
- Heterotopic Ossification
- Avascular Necrosis
- Post-traumatic Arthritis
- One of the most common complications[10]
- Loss of range of motion
- Poor elbow function
- Elbow instability
- Need for hardware removal
- One of the most common complications[10]
See Also
Internal
External
- Sports Med Review Elbow Pain: https://www.sportsmedreview.com/by-joint/elbow/
References
- ↑ Bryan RS, Morrey BF. Fractures of the distal humerus. Philadelphia: WB Saunders; 1985.
- ↑ Khalili M, Wong RJ. Underserved Does Not Mean Undeserved: Unfurling the HCV Care in the Safety Net. Dig Dis Sci. 2018 Dec;63(12):3250-3252. doi: 10.1007/s10620-018-5316-9.
- ↑ Image courtesy of musculoskeletalkey.com
- ↑ Sun, Weitong, et al. "Relationship between measurements of ipsilateral capitellum and prosthetic radial head size." Journal of Orthopaedic Surgery and Research 17.1 (2022): 496.
- ↑ Image courtesy of grepmed.com
- ↑ Watts, A. C., A. Morris, and C. M. Robinson. "Fractures of the distal humeral articular surface." The Journal of Bone & Joint Surgery British Volume 89.4 (2007): 510-515.
- ↑ Case courtesy of Dr Samir Benoudina, Radiopaedia.org, rID: 67687
- ↑ 8.0 8.1 Gonçalves Pestana, José António, et al. "An unusual case of an isolated capitellar fracture of the right elbow in a child: a case report." Journal of medical case reports 6 (2012): 1-6.
- ↑ Coronal Shear Fractures of the Distal End of the Humerus*. (1996) The Journal of Bone and Joint Surgery-american Volume. 78 (1): 49. doi:10.2106/00004623-199601000-00007
- ↑ 10.0 10.1 10.2 Heller, Mike, et al. "Rate of complications after Capitellum fracture fixation: a systematic review and Meta-analysis." The Journal of Hand Surgery (2023).