Original Editor - --Marie Avau , Debby Decock, Farrie Bakalli, Margaux Jacobs
- 1 Definition/ Description
- 2 Clinically Relevant Anatomy
- 3 Epidemiology/ Etiology
- 4 Characteristics/Clinical Presentation
- 5 Differential diagnosis
- 6 Diagnostic Procedures
- 7 Outcome Measures
- 8 Examination
- 9 Medical management
- 10 Physical Therapy Management
- 11 Key research
- 12 Resources
- 13 Clinical Bottom Line
- 14 References
A metacarpal fracture is a break in one of the five metacarpal bones of either hand. Metacarpal fractures are categorized as being fractures of the head, neck, shaft, and base (from distal at the metacarpal phalangeal joint to proximal at the wrist).  (level 5)
Thereby we also have the Boxer fracture, this is another name for a fracture of the fourth or fifth metacarpal. This is one of the most common metacarpal fractures, in contrast with the fractures of the thumb (Bennett’s and Rolando’s fracture). (Blomberg et al, level 5)
Clinically Relevant Anatomy
The hand is composed of 19 bones (5 metacarpals and 14 phalanges), more than 30 tendinous insertions and numerous complex structures. The metacarpals are long, thin bones which are located between the carpal bones in the wrist and the phalanges in the digits.
Each are comprised of a base, shaft, and head. The proximal bases of the metacarpals articulate with the carpal bones, and the distal heads of the metacarpals articulate with the proximal phalanges and form the knuckles. The 1st metacarpal (of the thumb) is the thickest and shortest of these bones. The 3rd metacarpal is distinguished by a styloid process on the lateral side of its base. Soft tissues generally involved with fractures include cartilage, joint capsule, ligaments, fascia, and the dorsal hood fibers. With severe polytrauma cases, the tendons and nerves adjacent to the fracture can also be injured. 
Muscles in the metacarpal region: 
There are three palmar and four dorsal interossei muscles that arise from metacarpal shafts. We can also find the insertion of extensor carpi radialis longus and brevis at the base of the second and third metacarpal. This muscles assist with wrist extension and radial flexion.
In the wrist we can thereby also find the extensor carpi ulnaris muscle, which inserts on the base of metacarpal five. His function is to extend and fixe the wrist when the digits are being flexed and assists with ulnar flexion of wrist.
The abductor pollicis longus is situated in the area of the thumb. It inserts on the trapezium and base of metacarpal I and is responsible for abduction of the thumb in the frontal plane and extends the thumb at the carpometacarpal joint. At this site we can also find the opponens pollicis, which inserts on metacarpal I and functions as a flexor of metacarpal I to oppose the thumb to the fingertips.
The final muscle at this site is the opponens digiti minimi, it inserts on the medial surface of metacarpal V, flexes metacarpal V at carpometacarpal joint.
Hand injuries constitute 5-10% of emergency department visits. The most common mechanisms are road traffic accidents, blunt trauma (e.g. crush injury, contusions), and assault. Fifth metacarpal fractures occur more frequently and are responsible between 16% to 34% of the hand fractures. (McNar, level 5) ,
Men, aged 10-29, have the highest incidence rates for metacarpal fracture (2.5 per cent). Accidental fall is seen as the dominant cause of these fractures this fall is mainly caused by transport accidents and in particular bicycle transport.The main cause of most metacarpal fractures of the fingers is a direct forceful blow on the fingers. For example, punching a solid object with a closed fist, or having a heavy object land on the hand. Occasionally they may also occur due to a direct impact to the hand, from an object travelling at high speed or a fall onto the fingers or thumb. (Bahubali Aski et. Al, level 4)
The thumb metacarpal fractures, which is the most common fracture type, are usually caused by an axial blow directed against the partially flexed metacarpal. (It is estimated to occur in 4% of hand fractures. (Stanton et al., 2007)) These fractures are called Boxer's fractures and received their name from one of their most common causes of punching an object with a closed fist. This occurs commonly during fist fights or from punching a hard object such as a wall or filing cabinet. Although these breaks usually occur when the hand is closed into a fist, they can also occur when the hand is not clenched and strikes a hard object. (Bahubali Aski et. Al, level 4)
The fractures of the metacarpals can be divided in three parts. The first, neck fractures, occurs often when a person punches another person or object. In the majority of cases, surgical intervention is not essential to treat this condition. The metacarpal shaft fractures are often produced by longitudinal compression, torsion or direct impact. They are described by the appearance of their respective fracture patterns and can be divided by transverse, oblique, spiral and comminuted. The last one is the metacarpal base fractures. They are rare and have minimal consequence because the motion of the joint is small. More common are the fractures of the base of the fifth digit and are the result of a longitudinally directed force 
Patients with metacarpal fractures generally present with: 
- Ecchymosis (bruise)
- Limitation of movement
- Deformity. Knuckle asymmetry may be observed, and the knuckle may appear to be missing.
- Finger misalignment may also be noted.
- A metacarpal head fracture is associated with axial compression of the extended digit which causes severe discomfort.
- In a metacarpal base fracture, movement of the wrist or longitudinal compression exacerbates the pain.
- Any metacarpal fracture angulation can produce a pseudo-claw deformity.
We can distinguish different types of metacarpal fractures: base fractures, shaft fractures, neck and head fractures. These fractures can either be displaced (shifted) or non- displaced They all have a specific cause and clinical presentation. Globally these patients all report a snapping or popping sensation.
Metacarpal Base Fractures: These fractures are intra-articular and result from high forces (violent accidents), direct blows, or crushing injuries that disrupt the rigid carpal ligaments, or overwhelm the normal flexibility of the ulnar metacarpals. They also occur with an avulsion of the wrist flexors or extensors, that insert on the metacarpal base, resulting from a direct blow or torsional injury. The most common occurrence is at the 5th metacarpal-hamate articulation. The healing rate varies from three to six weeks.
Metacarpal Shaft Fractures: These fractures are extra-articular and are caused by longitudinal compression, torsion, or direct impact that may result from a fall, blow, or crushing force that usually angulates dorsally. They are described by the fracture configuration as transverse, oblique, spiral, or comminuted. Metacarpal shaft fractures are slower to heal than the more distal or proximal locations because of the predominantly cortical bone found there. The healing rate varies from three to seven weeks
Metacarpal Neck Fractures: Most common metacarpal fracture. The weakest point of the metacarpal bone is the extra-articular neck. These fractures result from a compression force such as a direct blow with a closed fist. The 4th and 5th metacarpals are most often involved and are referred to as a “fighter’s” or “boxer’s” fracture. Trauma causes the fractured metacarpal head to displace with volar angulation. The healing rate is three to five weeks.
Metacarpal Head Fractures: These fractures are intra-articular and are caused by direct impact and high axial loads that can involve avulsion of the collateral ligaments, including a fracture fragment, fracture of one or both condyles, or shattering of the joint surface into many small, comminuted pieces. ( deze tekst stond op de originele Physiopedia pagina, maar was niet onderveeld in het juiste puntje)
Problems in the metacarpal region can also be diagnosed as a skier’s tumb, a metacarpophalangeal joint dislocation or a hand dislocation. These disorders often present with the same symptoms and can be confused with a metacarpal fracture. It is thus important to distinguish both injuries. 
To diagnose a metacarpal fracture, it is necessary to submit the patient to a physical examination and radiograph; these can be can be considered as the definitive standard for diagnosis of metacarpal fractures. 
Different types of diagnosis:
- Physical examination of a suspected metacarpal fracture should concentrate on hand deformity, tenderness, digit mal rotation, and presence of open wounds. Painful range of motion, point specific bone tenderness and ecchymosis should be considered red flags for fractures.
- Routine radiographs include three views: antero-posterior, lateral, and oblique. These views assist in properly assessing angulation of fracture fragments as well as involved joint surfaces. Computed Tomography scans, or CT scans, may be ordered to evaluate complicated fractures.
- Ultrasonography: this type of diagnostic procedure is especially used in scaphoid fractures, as it’s only proven reliable and accurate for this specific type.
- Another technique is the bone scintigraphy (this is an imaging technique using radioactive substances that intravenously was injected in small quantities, also called a bone scan)
- An MRI is almost never necessary for an isolated metacarpal fracture, as they normally don’t add any further information beyond a regular x-ray. But if other injuries are suspected, an MRI can be used as a supplementary test.
-Grip Strength: measured with a dynamometer
-Range of motion
-Disabilities of the Arm, Shoulder, and Hand score (QuickDASH): this questionnaire is scored in two components: the disability/symptom section (30 items, scored 1-5) and the optional high performance Sport/Music or Work section (4 items, scored 1-5).
-Michigan Hand Outcome Questionnaire (MHO): In this questionnaire they asses 6 criteria for people with a hand disorder: overall hand function, activities of daily living (ADL), pain, work performance, aesthetics, and patient satisfaction with hand function. 
-Patient Evaluation Measure (PEM): this questionnaire is similar to the DASH score and assesses the hand function by asking questions about the patients pain, tenderness, swelling, wrist movement and grip strength.
- The Hand Clinic Questionnaire: has eight questions addressing pain, stiffness, neurological change, use of the hand and appearance 
- The Patient Evaluation Measure uses visual analogue scales and has three parts: The first part seeks the patient’s opinion on the delivery of care. The second part is entitled ‘‘How your hand is now’’ (Hand Health Profile) and has ten questions concerning feeling, cold sensitivity, pain frequency, use for fiddly (fine dexterous) activities, movement, grip strength, activity, use for work, appearance and general attitude. The third part has three questions, which cover the overall assessment of outcome after the injury.
- The HOSS is a doctor-administered form and combines both subjective and objective measures.
The HOSS measures the injury in four tissues: integument, skeletal, motor and neural. These four tissues and their degree of impairment form the basis for measuring the outcome in the HOSS.
Reliability and validity of the outcome measures: 
- Michigan Hand Outcome questionnaire: test-retest reliability was measured using Spearman's correlation and demonstrated substantial agreement, ranging from 0.81 for the aesthetics scale to 0.97 for the ADL scale. In testing for internal consistency, Cronbach's alphas ranged from 0.86 for the pain scale to 0.97 for the ADL scale. Correlation between scales gave evidence of construct validity.
- PEM, DASH and MHO all have a good construct validity, but the easiest to use and complete is the PEM questionnaire. They are valid and reliable for wrist and finger disorders. 
The severity of the fracture is evaluated by taking several X-rays of the hand. We can include three views:
1. Anteroposterior view: When a x-ray is taken from front to back, with the back against the film plate and the x-ray machine in front of the patient it is called an anteroposterior (AP) view. 
2. Lateral view: the x-rays beam enters through the lateral side of hand
3. Oblique view: the view is obtained from a pronated, palm-down position by rotating the hand 45° laterally. 
- Brewerton’s view: a view used to detect occult fractures of the metacarpal head
- Skyline view: they are used for the fracture head of the metacarpal bone
- 30° pronated and 30° supinated oblique view: it is warranted for the 2nd and 5th metacarpal shaft fracture
- Stress view: it may indicate certain fracture dislocations
- CT-scan (computed tomography): it uses computer-processed X-rays to make tomographic images. It evaluate the metacarpal-carpal joints in complicated fractures.
- MRI (magnetic resonance imaging): it is used to investigate the physiology and anatomy of the body.
The above-mentioned techniques are rarely used in acute skeletal injuries of the hand.
“Evidence for the effective therapy management of these fractures is sparse, varied and of poor quality and does not provide a ‘gold standard’ therapeutic treatment approach.”  (A. Toemen et al)
Knowledge of different therapies, the relevant anatomy, acting muscular forces and the mechanisms of fractures is required to choose the appropriate treatment modality for metacarpal fractures. Thereby, it is important to remember that the medical treatment must not sacrifice the hand functions as they are used in daily life. (McNar et al, level 5)
As with any hand fracture, the primary goals are to achieve anatomic and stable reduction, bony
union, and early mobilization to minimize disability.
We can distinguish stable and unstable fractures. A stable fracture sustains an acceptable position at rest when early mobilization are introduced. Unlike unstable fracture, which are likely to displace with early mobilization. The latter is first managed with a period of immobilization or surgical intervention for stabilization. (level 4)
Stable fractures will not lose approximation with muscle tension or controlled motion.
First, closed methods of supports are used for 2-3 weeks and then a removable splint for controlled motion is applied. (McNar el al, level 5)
Potential unstable fractures are those that are aligned, but may get misaligned with certain positions or tension. These are treated with immobilization that maintains reduction or restriction of motion towards position of instability. As healing occurs, immobilization can be modified to allow incremental increases in ROM.
Unstable fractures are those that do not maintain reduction. Displacement occurs even with immobilization. Fixation devices are warranted. An unstable fracture can be managed with early mobilization as long as a protective resting splint is used. In such case, a clinical and radiographic follow-up is needed to ensure the undisplaced state of the fracture. Surgical intervention is used when an acceptable displacement occurs.  (McNar el al, level 5) 
Two facts must be provided with therapy referral: date of fracture and method of fixation. Date of fracture provides a timetable on where the bone healing process is. Knowing the method of fixation will determine when motion can be introduced. Open reduction fixations (implementation of implants to guide the healing process of bone) can begin AROM (active range of motion) earlier.
If there is no intervention, most digit factures will unite. Therefore early mobilization is important to maintain and regain mobility. 
The evaluations of rotational malalignement and stability of these unstable fractures are the most critical elements to choose between operative and non-operative treatment. The latter is cheaper and avoids complications of surgical treatment. There is a chance that it may not restore skeletal position and maintain stability. Open surgery can accomplish the most stable anatomic reduction. Important to notice is that if there has been an aggressive surgeon’s intervention, a more aggressive post-operative rehabilitation is required.
In recent literature, studies were executed to evaluate the outcome measures in patients with a metacarpal fracture, who received different medical treatments.
1. Transverse and short oblique closed metacarpal and proximal phalangeal fractures treated with intramedullary -wire and cross -wires had produced favorable and comparable outcomes in long term. (Singh Ashutosh K et al, level 4)
2. When immobilization was discontinued by five weeks, the position of the metacarpophalangeal joints and the absence or presence of interphalangeal joint motion during the immobilization had little effect on motion, grip strength, or fracture alignment. This finding contradicts the conventional teaching that the metacarpophalangeal joint must be immobilized in flexion to prevent long-term loss of joint extension. (Tavassoli J1 et al, level 2C)
Physical Therapy Management
Such as Giddins says “most hand fractures can be treated non-operatively”  (Giddins et al, level 2A), which accentuates the important role of the physical therapist in the healing process. But some hand fractures, such as open injuries or displaced intra-articular fractures, are almost always treated operatively. In this section, we will discuss de the modalities and role of the physical therapist after a metacarpal fracture.
In early phases of therapy, patient should be educated on edema control. Rest, ice, compression, and elevation should be emphasized.The intervention of the physical therapist consist of applying powertraining modalities or guide the healing process by using a splint. Alongside of improving the functionality, active, passive and resistive exercises also affect the recovery process of bone and cartilage.
Before the physical therapist can start the interventions or treatment, certain considerations about the fracture should be made. These are the steps to be followed in a stable fracture:
 Maureen A. et al (level of evidence 5)
Buddy strapping the injured digit to another digit is used as a non-operative technique. This is used with or without the application of varying degrees of splint. The ‘buddy’ reduces the risk of rotational deformity. The splinting of the fracture should be with an aim if 20 degrees wrist extension, the metacarpophalangeal joint in 60-70 degree flexion and interphalangeal joint extension  (HAUGHTON et al, Level of evidence 5).
Early motion is generally considered appropriate when there are stable fractures or rigid fractures. It is hypothysed that early motion has the potential for improved outcomes. (LM Feehan et. Al, level of evidence 3A)
Generally AROM (active ROM) exercises without resistance can begin 2 to 3 weeks after operative treatment in uninvolved or bordering/adjacent joints. (Stern PJ., level of evidence 5), ( Feehan LM. ,level of evidence 5),  (Rafael D. Et al., level of evidence 5) , 
Active Motion: If the fracture is internally fixed, the active range of motion can start early. Most fractures are treated by immobilization, but the active motion can begin after three weeks of therapy, starting with the joints not splintered during the initial immobilization. This phase usually lasts 3-6 weeks.  (Tim L et al., level 5),  (Sadler JA, Koepfer JM et al, level 5),  (Maureen A. Hardy, level 5),  (Heiser, R., et al. level 2A)
Specific tendon gliding should be included in the active motion. The following muscles should be involved: m. flexor digitorum profundus, m. flexor digitorum superficialis, m., extensor digitorum communis, m. extensor indicis propius and m. extensor digiti minimi
Tendon gliding is important to prevent adhesions,increased circulation about the fracture site, decreased edema and compression at the fracture site.
FDP tendons and selected tendon glide should be performed by actively flexing the injured PIP joint while positioning the other DIP joints in extension. The EI and EDQ tendons should glide on the adjacent EDC tendon and the EDC tendons on the underlying bone. By extending the MPC joints while IP joints are flexed, tendon gliding of the EDC tendon should be performed.
Exercises for tendon gliding :
A : Claw posture to achieve extensor digitorum communis tendon glide over metacarpal bone
B : Intrinsic plus posture to achieve central slip. Lateral bands glide over proximal phalanx 1
C : Flexor digitorum profundus (FDP) blocking exercises to glide FDP tendon over phalanx 1
D : Hook fist posture to promote selective FDP tendon glide
E : Flexor digitorum sublimis blocking exercise to glide FDS tendon over middle phalanx
F : Sublimis fist posture to promote selective FDS tendon glide
 (Maureen A. Hardy, level 5)
Passive Motion: Passive motion can be initiated during the repair phase, when callus is starting to form. This motion will stimulate bone and cartilage healing. The passive range of motion (PROM) can be divided in physiological motion or arthrokinematic motion. Passive motion can be initiated after sufficient clinical healing at approximately 5-6 weeks of therapy.  (Tim L et al., level 5) ,  (Calandruccio JH. et al, level 5),  (Sadler JA, Koepfer JM et al, level 5)
Once the therapist knows the location of the fracture, joint mobilization can be started. It is preferable to applicate arthrokinematic motion before traditional PROM. The force in physiological PROM is applied at a distance from the joint axis of motion, which can be produced extra load around the fracture site. For arthrokinematic motion, the force is directed perpendicular to the joint surface, which is not stressing the fracture site.
The timing of initiation of joint mobilization depends on the structures involved in the injury. If the structures resisting the force are not involved in the injury, joint mobilization can be initiated at the same time as active motion. Compression on the fracture can result in shortening, angulation or rotational malalignment of the bone.
Traditional PROM aims to assist in articular cartilage healing, reduce swelling and stiffness. Continuous passive motion (CPM) is a form of PROM. It applies force through the phalanx, thus applies a torque to the fracture site. CPM has the potential to decrease edema and improve synovial fluid production. CPM can be applied as soon as traditional PROM is allowed. However, Continuous passive motion can never replace active and resistive exercise and the application of CPM should not be painful.
Important to know is that a full PROM is necessary before full AROM and ultimate function of the hand can be achieved.  (Jagannath B et al. level of evidence 5)
Four weeks after the injury light resistance can be performed in most metacarpal fractures which are treated by immobilization. Active motion should only be continued if healing has not started. Resistive exercise should also be delayed when a fracture is fixed by pinning until these pins are removed, to ensure stability of the fracture.
Light resistive exercise helps with scar remodeling and improved motion. There are several types pf resistive exercises such as the weight-well exercises. This kind of exercise strengthens the finger flexors (FDP and FDS muscles). Functional activities and work simulation should be included in the resistive exercises as soon as possible.(Sander Richards Saunders, level of evidence 5)
Hardy MA. Principles of Metacarpal and Phalangeal Fracture Management: A Review of Rehabilitation Concepts. Journal of Orthopedic and Sports Physical Therapy. 2004; 34:781-791.
Hand and Metacarpal Fractures
Clinical Bottom Line
Bottom line (=The main or essential point)
A metacarpal fracture is a break in one of the five metacarpal bones of either hand. It is categorized as being head fractures, neck fractures, shaft fractures and base fractures. These fractures can either be displaced or non- displaced. The main cause of most metacarpal fractures of the fingers is a direct forceful blow on the fingers. Each fracture-type has specific clinical presentation.
In some cases, there may be a wrong diagnosis for a metacarpal fracture because other disorders often present the same symptoms. Because of that, it is necessary to submit the patient to a physical examination and radiograph. By taking several X-rays of the hand, the severity of the fracture can be evaluated.https://www.youtube.com/watch?v=uWQtpqXRx-w
Medical treatment must not sacrifice the hand functions. The primary goals of medical management are to achieve anatomic and stable reduction, bony union, and early mobilization to minimize disability. Knowledge of the relevant anatomy, acting muscular forces and the mechanisms of fractures is required to choose the appropriate treatment.
The intervention of the physical therapist consist of applying strength exercises or guide the healing process by using a splint. Alongside of the improved functionality, active, passive and resistive exercises also affect the recovery process.
- http://www.physioadvisor.com.au/14681850/metacarpal-fracture-physioadvisor.htm (level of evidence 5)
- Blomberg J, Metacarpal fracture, Orthobullets & oral boards, 2014 (level of evidence 5)
- Rafael D. Et al., Current management of metacarpal fractures, hand the clinics, 2013 (level of evidence 5)
- Hardy MA. Principles of Metacarpal and Phalangeal Fracture Management: A Review of Rehabilitation Concepts. Journal of Orthopedic and Sports Physical Therapy. 2004; 34:781-791.(level of evidence 5)
- Karriem-Norwood, Boxers fracture, webmd , 2014
- J. J. de Jongel et al, Fractures of the metacarpals. A retrospective analysis of incidence and aetiology and a review of the English-language literature, ‘Department of Traumatology, and ‘Department of Plastic and Reconstructive Surgery, University Hospital Groningen, The Netherlands. Injury, 1994, Vol. 25, 365-369, August.
- Kathleen M. Kollitz et. Al., Metacarpal fractures: treatment and complication, American Association for Hand Surgery 2013, Springer, Published online: 16 October 2013, HAND (2014) 9:16–23
- Michael DelCore ,Metacarpal fractures, orthopaedicsone ,2015.
- T. GRANT PHILLIPS, M.D. et al, Diagnosis and Management of Scaphoid Fractures, Washington Hospital Family Practice Residency, Washington, Pennsylvania, 2004.http://coruraltrack.org/wp-content/uploads/2013/01/Scaphoid-Fractures-AFP.pdf
- Tiel-van Buul MM et al, The value of radiographs and bone scintigraphy in suspected scaphoid fracture. A statistical analysis. J Hand Surg [Br] 1993;18:403-6.