ribcage

Figure 7.1

Bones of the human thorax, showing the ribcage

Introduction

Along with injuries to the thoracic spine, rib musculoskeletal injuries have been researched in less depth than injuries to other areas. But injuries to the ribs are not uncommon, particularly in athletes, where they can be caused by repetitive and extreme forces put through the ribcage during exercise. Rowers, for example, are at risk of rib fractures, and it is interesting that the incidence in elite rowers is higher than in amateur rowers (McDonnell et al 2011). Rib fractures are not restricted among sports players to rowers, however, and they can occur in golfers (Bugbee 2010), lacrosse players (Wild et al 2011), weightlifters (Eng et al 2008, Miller 2015), individuals involved in martial arts, and boxers (Gartland et al 2001, Zazryn et al 2006), and in any sport that has an impact component, such as rugby and American football (Feeley et al 2008, Brooks & Kemp 2011). Although less common, rib fractures have also been reported in swimmers (Chaudhury et al 2012, Heincelman et al 2014), possibly caused by high repetitive strains placed upon the ribcage during overhand swimming motions. Not caused exclusively by repetitive loading during sporting activities, fractures of the ribs can also be caused by occupational stresses, such as in manual labor (Miller et al 2013).

Fractures are not the only ribcage injury that can occur in athletes or individuals with manual occupations. Another is intercostal muscle strain, again frequently seen as a result of sporting activities, including baseball (Stevens et al 2010, Conte et al 2012), cricket (Cam et al 2006, Milsom et al 2007), tennis (Maquirriain & Ghisi 2006, García & Ros 2011) and football (Durandt et al 2009). These sports all involve forced and repetitive rotation of the thorax, which predisposes a patient to suffer with costal and intercostal symptoms. For safety reasons, the therapist must always rule out the possibility of a fracture before proceeding with examination and treatment of any patient presenting with these symptoms.

Chest problems are extremely widespread. It has been projected that, by 2020, chronic obstructive pulmonary disease (COPD) will be the fourth-highest cause of death (Patel & Hurst 2011). The current cost to the NHS in the United Kingdom is estimated to be over £800 million a year, and this figure is set to rise as life expectancy increases (Fromer 2011). Manual therapy in the form of physiotherapy for pulmonary rehabilitation, physical exercise and hands-on treatment is a mainstay in respiratory wards in hospitals (Benzo et al 2000, Hondras et al 2005). The principal aims of this therapy are to encourage fluid dynamics (i.e. the movement of mucus within the lung and airways) and to increase lung capacity. This is attempted by the use of several different types of breathing technique (Thomas et al 2009, Bruton et al 2011). Although research seems to support the beneficial use of breathing exercises, studies into the effectiveness of manual therapy and treatment of COPD have so far proved inconclusive. There has been some research into the effects of osteopathic and chiropractic treatments on COPD, but most of this is based on manipulation of the thoracic spine and costotransverse joints rather than the ribcage. Some of the treatments may be effective in helping some of the conditions associated with COPD, but most of the evidence to date is anecdotal or not statistically significant (Noll et al 2000, Hondras et al 2005, Ernst 2009a, 2009b, Kaminskyj et al 2010, Heneghan et al 2012, Engel et al 2014).

Bony anatomy

The ribcage, also called the thoracic cage, is an osteocartilaginous frame in the thorax that forms a core portion of the human skeletal system. It shields the vital organs of the body, provides attachment sites for muscles, and forms a semi-rigid chamber that can expand and contract during respiration (White & Folkens 2005). Anatomically, the ribcage is an arrangement of bones and cartilages that encloses the chest cavity and supports the shoulder girdle and upper extremities. Structurally, it appears broad below, narrow above, longer behind and flattened anteroposteriorly (Datta 1994).

A ribcage is typically made up of 12 pairs of ribs with their costal cartilages, the sternum and the 12 thoracic vertebrae (Mader 2004). Men and women usually have the same number of ribs; a few reports have identified an anatomical variation in the number of ribs, but most of those were associated with a variation in the number of thoracic vertebrae. Each pair of ribs is symmetrically in articulation with a thoracic vertebra on the right and left side. The sternum consists of the manubrium (prosternum), an intermediate body (mesosternum or body) and xiphoid process (metasternum) (see Figure 7.1). At the chest, many of the ribs are connected to the sternum via costal cartilages (Joshua et al 2014).

The ribs

The ribs are long, curved bones with a rounded and a flattened end. The rounded ends (head of the rib) articulate posteriorly with the T1–T12 thoracic vertebrae via a synovial joint articulation; most of the flattened ends attach anteriorly to the sternum via costal cartilages. These cartilages are hyaline in type and can extend for a few inches/centimeters (Open-Stax 2013).

The ribs are divided into two groups based on their anterior and posterior attachments. Anteriorly, the ribs are classified into two further groups: true and false ribs. The first seven pairs of ribs (1–7) are called the true ribs, or the vertebrosternal ribs, because they attach directly via their costal cartilages to the sternum. The next five pairs of ribs (8–12) are called the false ribs, or vertebrochondral ribs, because they do not attach directly to the sternum. Ribs 8–10 are attached indirectly to the sternum, as their costal cartilages ventrally attach to the cartilage of the ribs above. The last two pairs of false ribs (11–12) are known as floating ribs, or vertebral ribs, because they do not attach to the sternum at all (Mader 2004).

Posteriorly, the ribs are classified as typical and atypical ribs. Ribs 3–9 are classified as typical ribs, and ribs 1, 2 and 10–12 are atypical. The typical ribs have similarities in their structure. The head, or the posterior end, of a typical rib articulates with two costal facets on the bodies of two adjacent vertebrae and the intervertebral disc between them. The superior rib facet articulates with the costal demifacet on the body of the next higher vertebra, and the inferior rib facet attaches with the costal demifacet of the same numbered thoracic vertebra (Warwick 1973). The tubercle, a small bump on the posterior rib surface, attaches to the transverse process of the same vertebra. The neck of a typical rib is narrow and is between the head and tubercle. The remainder is the body, or shaft, of the rib. Just lateral to the tubercle is the angle of the rib, which is the point of greatest curvature (Cropper 1996).

The atypical ribs have structural features that are very different from the typical ribs. Apart from rib 2, all of the atypical ribs have only one demifacet on their head for articulation. Rib 2 is considered atypical because it attaches to the junction of the manubrium and the body of the sternum (Bourdillon et al 1992).

The sternum

The sternum, or breastbone, is an elongated bony structure that is slightly concave posteriorly and convex anteriorly. It is composed of three bones: the manubrium, the body, and the xiphoid process. Structurally, the sternum bears a resemblance to a sword, with the manubrium forming the superior portion (the handle), the body forming the central portion (the blade), and the xiphoid process forming the inferior and smallest portion (the tip) (Tate 2009).

At the top of the manubrium, there is a shallow depression, a U-shaped border, called the jugular (suprasternal) notch. This can easily be found at the anterior base of the neck, between the medial ends of the clavicles where they attach to the sternum (Open-Stax 2013). At the junction of the manubrium and the body, there is a slight ridge, called the sternal angle. This joint is a vital anatomical landmark because rib 2 articulates with the sternum at the sternal angle; as a result, it allows the ribs to be counted (Mader 2004).

The body is the middle and longest region of the sternum. It is wider inferiorly than superiorly and is flatter than the manubrium. The xiphoid process is the most inferior region of the sternum. It is cartilaginous early in life, but gradually becomes ossified in adulthood. The xiphoid process functions as a site of attachment for the diaphragm (Cropper 1996).

The manubrium attaches to the costal cartilages of ribs 1 and 2; the body connects the costal cartilages of ribs 2 to 10; the xiphoid process has no attachment with any ribs (Mader 2004).

Range of motion

The ribcage provides the thoracic mobility required for breathing. This mobility is attributable to the sternal and vertebral joints and the costal cartilages at either end of the rib structure. More precisely, movements of ribs primarily rely on the orientation of costovertebral and costotransverse joints, which are subjected to continual movement. Apart from its contribution during respiration, the ribcage can undergo movement if a misfit occurs at the costovertebral joint surfaces or external forces are applied to the chest, such as traumatic loading of the chest and cardiopulmonary resuscitation (Yoganandan & Pintar 1998).

The movements of the ribs are normally around two axes. The upper rib motion resembles a ‘pump handle’ and the lower rib motion resembles a ‘bucket handle’. The axis for rib motion is represented as a line running between the costovertebral joint and the costotransverse joint via the rib neck. The axis for upper rib rotation (ribs 2–6) orients toward the frontal plane, whereas the lower ribs (excluding ribs 11 and 12) lie more toward the sagittal plane. Movement at the upper ribs about a side-to-side axis therefore results in elevation and depression of the sternal end of the rib. Conversely, motion of the lower ribs about an anteroposterior axis raises and lowers the middle of the rib (Cropper 1996).

Epidemiology

Rib fractures are one of the most common injuries to the chest, occurring in approximately 10% of all patients admitted after blunt trauma (Liman et al 2003). Melendez and Doty (2015) suggest that rib fractures account for over 50% of all thoracic injuries from non-penetrating trauma. They are usually uncommon in children of all ages, accounting for only 1% of all fractures in children (Hedström et al 2010). In ex-preterm infants, the prevalence of rib fractures in contemporary tertiary neonatal centers is approximately 2% (Lucas-Herald et al 2012).

The rate of multiple rib fractures is higher in adults than children. In a retrospective cohort study, Kessel et al (2014) found 11% of adults suffered from isolated rib fractures without associated injuries compared to 5.8% of children. More adults had four or more rib fractures than children did. However, the study reported a slightly higher mortality rate in children compared with adults (5.18% in children and 4.93% in adults).

The overall incidence of associated injuries, including brain and solid organ injuries, pneumothorax or hemothorax and lung contusion, in children is significantly higher than in adults. In adults, motor vehicle accidents were found to be the most common mechanism of injury; in children the most common mechanisms of injuries were pedestrian hit by car, bicycle accidents and child abuse (Bergeron et al 2003, Sirmali et al 2003).

In elderly people (age 65 or over), rib fractures are the most common non-spine fractures. Barrett-Connor and colleagues (2010) reported that the annual incidence of rib fracture was 3.5 per 1000 individuals, accounting for 24% of all non-spine fractures. Nearly 50% of the fractures reported resulted from falling from standing height or lower. The study also suggested a number of independent risk factors for rib fractures. These include a baseline history of rib or chest fracture, low bone density, difficulty in activities of daily living with instruments, and age 80 or above.

Common pathological conditions of the ribcage are shown in Table 7.1.

Ribcage examination

Medical history

While examining the ribcage of the patient, taking a detailed medical history of the patient’s past and present problems is as essential as the physical examination itself. In most cases, the narrative provided by the patient consists of information critical to narrowing the differential diagnosis and facilitating the physical examination.

Condition	Description	Reference
Costochondritis	An acute and often temporary inflammation of the cartilage that attaches a rib to the sternum May result in sharp chest pain and tenderness More than one site is affected in 90% of cases May affect any of the seven costochondral junctions Occurs most frequently in females and in people over age 40	Jindal & Singhi (2011), Flowers (2015)
Rib fracture	Often results from a direct blow to the chest, but may also occur because of coughing or forceful muscular activity of the upper limb or trunk Most frequently affects ribs 7 and 10 Occurs more predominantly in older people than in younger adults Symptoms include severe well-localized pain, pain during deep inspiration or with movement, and grating sound with breathing or movement	Ombregt (2003), Melendez & Doty (2015)
Tietze syndrome	A rare, inflammatory disorder of one or more of the costal cartilages in the superior ribs Characterized by a sudden or a gradual on-set of unilateral pain and swelling of one of the costosternal synchondroses Often occurs at the second rib pair Equally prevalent in men and women Affects people of all ages, including children	Kayser (1956), Proulx & Zryd (2009)
Manubriosternal arthritis	Affects the manubriosternal joint Can occur as a result of rheumatoid arthritis or ankylosing spondylitis One of the major symptoms is spontaneous pain at the angle of Louis May show subchondral cysts, narrowing of the joint space, erosion of the joint margin and sclerosis of bone close to the joint in radiographic analysis	Sebes & Salazar (1983), Ombregt (2003)
Intercostal neuralgia	Defined as an intense, sharp, shooting or burning pain Can be caused by a traumatic or iatrogenic neuroma, persistent nerve irritation or herpes zoster (shingles) Some association with post breast and abdominal surgery	Santos et al (2005), Ducic & Larson (2006), Williams et al (2008)

Table 7.1
Common pathological conditions of the ribcage

The clinician must approach the patient in a friendly and respectful manner. They should collect the necessary information in a logical format and must listen to the patient’s responses very carefully. Apart from questioning about pain, swelling, tenderness or any other issues related to the ribcage, they must inquire about the onset of the problem, behavior since onset, symptom pattern(s), and exacerbating and relieving factors.

Red flags

See Table 7.2.

Physical examination

When the history taking is done, the clinician will have enough information to make tentative decisions about certain aspects of the condition. The clinician should then carry out the physical examination. This usually involves inspection, palpation and a variety of special tests for the chest.

Inspection

The physical examination process usually starts with a careful visual inspection of the patient’s ribcage. It is helpful to inspect the posterior thorax while the patient is sitting and the anterior thorax with the patient supine. The patient’s gown should be suitably arranged to allow complete inspection of the anterior and posterior thorax. During inspection of the thorax, the examiner should carefully observe the shape of the chest and the movement of the chest wall. If any asymmetry or deformities (e.g. thoracoplasty, pectus carinatum, pectus excavatum, gynecomastia, scoliosis, surgical or traumatic scars) are found, they should immediately be noted. The examiner should also note whether there is an impairment or unilateral lag (or delay) in respiratory movement. Any abnormal retraction of the interspaces during inspiration should also be noted (Bickley & Szilagyi 2012).

Condition	Signs and symptoms
Myocardial infarction	Chest pain or discomfort Pressure or tightness in the chest Shortness of breath, sweating, pallor, lightheadedness, nausea or tremors History of a sedentary lifestyle Previous history of ischemic heart disease, abnormally high blood pressure, diabetes, smoking, elevated triglyceride level and hypercholesterolemia Age: men over 40 years and women over 50 years Symptoms lasting for 30–60 minutes
Pericarditis	Sharp or stabbing pain over the center or left side of the chest Increased pain with deep breathing, swallowing, coughing or left side lying Relieved with forward leaning and sitting up Shortness of breath, heart palpitations, fatigue, nausea
Pneumothorax	Intensified pain the chest during inspiration, ventilation, or expanding of ribcage Abnormally rapid breathing Hypotension, dyspnea or hypoxia Distant or absent sounds of breath
Pneumonia	Sharp and piercing chest pain while breathing or coughing Fever, shaking chills, headache, sweating, fatigue or nausea Productive cough
Fracture	Greater than 70 years of age Recent history of major trauma Prolonged use of corticosteroids History of osteoporosis

Table 7.2
Red flags for serious pathology in the ribcage

Data from Dutton (2012), Magee (2014)

Palpation

While palpating the chest, the examiner should first place the palm of each hand on the upper portion of the thorax and then, softly but firmly, move the hand to the lower portion, just below the twelfth rib. The examiner repeats the same procedure, moving the hands laterally and subsequently anteriorly, feeling for rib deformities, areas of tenderness, respiratory expansion and abnormalities in the overlying skin. If a patient has a history of discomfort in the thorax, the examiner should carefully palpate the area(s) where pain has been reported. This should be done with increasing firmness to assess whether the pressure repeatedly elicits tenderness. If a patient is reporting anterior chest pain, particular attention should be given to the costochondral junctions, so that the possibility of costochondritis can be evaluated (Tuteur 1990).

Special tests

See Table 7.3.

Test	Procedure	Positive sign	Interpretation
Chest expansion test	Posterior examination: The therapist places their thumbs near to the 10th ribs. The fingers are in parallel to the lateral ribcage, loosely grasping the lower hemithorax on either side of the axilla. The clinician then slides their hands medially just sufficient to elevate a loose skin fold on each side between their thumb and the spine. The patient is requested to breathe and expire deeply. The therapist should then observe the space between their thumbs and feel for the symmetry of movement of the hemithorax.	Asymmetrical chest expansion Abnormal side expands less and lags behind the normal side	Unilateral decrease or delay in chest expansion indicates pathology on that side, such as lobar pneumonia, pleural effusion and unilateral bronchial obstruction Bilateral decrease in chest expansion usually suggests COPD or asthma
	Anterior examination: The therapist places their thumbs laterally to each costal margin, with their hands along the lateral ribcage. The therapist then slides their hands medially to elevate loose skin folds between their thumbs. The patient is requested to breathe and expire deeply. The therapist should then observe how far their thumbs move while the thorax expands, and feel for the depth and symmetry of the hemithorax movement.
Percussion	First, the therapist places the middle finger on the surface to be percussed. The distal phalanx of that finger should be pressed firmly, avoiding contact by any other fingers or part of the hand. With a quick but relaxed wrist motion, the therapist then strikes the finger placed directly on the thorax, using the other hand’s tip of the middle finger. The aim of the strike should be focused at the distal interphalangeal joint. The striking finger should quickly be withdrawn to avoid damping the vibrations. However, if the sound and the vibrations created seem unsatisfactory, the therapist should check whether the middle finger in contact with the thorax is making firm contact with the chest wall. Using the same technique, the therapist percusses the posterior, lateral and anterior chest wall of the patient. The percussion is usually done on one side of the chest and then the other side at each level. When the percussion on both sides is done, the therapist finally compares one side to the other.	Flatness, dullness or hyperresonance percussion notes	Flatness may suggest either solid or fluid material in the pleural space (e.g. fibrothorax, pleural effusion, mesothelioma and empyema) Dullness is often associated with an interstitial pulmonary process, but it may also suggest a restrictive ventilatory defect (e.g. lobar pneumonia) Generalized hyperresonance indicates hyperinflated lungs – possibly emphysema or asthma. Unilateral hyperresonance suggests a large air-filled bulla in the lung, or maybe an acute pneumothorax
Anterior–posterior rib compression test	For this maneuver, the patient can be in either sitting or standing position. The therapist stands laterally to the patient and places one hand on the anterior and another on the posterior aspects of the ribcage. The therapist compresses the ribcage by pushing the hands together and then releases the pressure. Anterior–posterior compression is favoured over lateral compression due to risk of pneumothorax if fracture is present.	The rib shaft being prominent in the midaxillary line Pain or point tenderness with the ribcage compression Respiratory restrictions for both inhalation and exhalation	Possibly a rib fracture, contusion or separation
Ribcage respiratory test	Ribs 1–10: The patient lies in supine position. The therapist palpates directly over the ribs anteriorly, particularly on the intercostal spaces. The patient is then asked to make a full inspiratory and expiratory effort. The therapist should then assess the respiratory excursion for the superior and inferior ribs.	One group of ribs stops moving first during either inhalation or exhalation	Rib dysfunction
	Ribs 11 and 12: The patient lies in prone position. The therapist’s hand is symmetrically placed over the 11th and 12th ribs posteriorly. The patient once again is asked to make a full inspiratory and expiratory effort. The therapist should then palpate the movement and assess the respiratory excursion.