Answer: C
After directly addressing the possibility of pneumothorax, hemothorax, pericardial effusion, rib fracture, pulmonary contusion, tracheal and great vessel injury, and cardiac contusion, we are left with a well appearing woman with focal chest wall trauma.
This woman is suffering from subluxation of the right 2nd and 3rd sternocostal joints. The mechanism of action is typically a direct blow to the shoulder or an oblique blow to the chest, most often seen in wrestlers and mixed-martial artists (but also in mountain bikers, motorcyclists, and others involved in high-impact sports).
The sternocostal joints have a difficult job description: be stable enough to support the thorax (which in turn protects vital organs) but be flexible just enough to allow fluid, effortless, constant gliding motion to aid in respiration. This stability is rooted in seamless layers; the soft articular capsules surround the joints between the cartilages of the true ribs and the sternum. The sturdier radiate sternocostal ligaments form membranous bands that send projections across the joint. Finally, the interarticular sternocostal ligament forms a thicker connection from the rib to the sternum.
This woman is suffering from subluxation of the right 2nd and 3rd sternocostal joints. The mechanism of action is typically a direct blow to the shoulder or an oblique blow to the chest, most often seen in wrestlers and mixed-martial artists (but also in mountain bikers, motorcyclists, and others involved in high-impact sports).
The sternocostal joints have a difficult job description: be stable enough to support the thorax (which in turn protects vital organs) but be flexible just enough to allow fluid, effortless, constant gliding motion to aid in respiration. This stability is rooted in seamless layers; the soft articular capsules surround the joints between the cartilages of the true ribs and the sternum. The sturdier radiate sternocostal ligaments form membranous bands that send projections across the joint. Finally, the interarticular sternocostal ligament forms a thicker connection from the rib to the sternum.
Gray’s Anatomy, 39th Ed.
Although strong and resilient, the fibrous capsules surrounding these joints can fail if enough force or torque is applied through a vector which the joint is not designed to resist. In our patient’s case, the structural integrity of the right 2nd and 3rd sternocostal joints is violated. This is a potentially life-threatening injury, due to the proximity of vital structures: just posterior to the medial third of the clavicle and the sternoclavicular joint lie the innominate artery and vein, vagus and phrenic nerves, internal and anterior jugular veins, trachea, and the esophagus. Immediately posterior to the sternum are the aortic arch, superior vena cava, and right
pulmonary artery.
Treatment of traumatic sternocostal subluxation depends on the stability of the joint. Surgical treatment is
guided by co-injuries identified or by the precariousness of the aforementioned proximal structures. After other
co-injuries are addressed, even grossly unstable joints rarely need surgical intervention: most isolated cases improve with supportive care alone. The goal is to reduce inflammation and allow for the natural sclerosis of the joint.
Tietze syndrome (B) is a benign focal inflammation and swelling of the costosternal joint, often caused by minor
trauma, repetitive motion, chronic cough, or a systemic illness such as viral syndrome. It can affect the
costosternal, sternoclavicular, or costochrondral joints. Tietze syndrome can be readily differentiated from costochondritis by its associated focal swelling and reproducible pain; costochondritis does not present with focal swelling; the pain is reproducible in multiple sites, often in the upper chest. Supportive care with an emphasis on PO fluids and a short course of NSAIDs is indicated.
Slipping rib syndrome (D) – also a diagnosis of exclusion – occurs when the anterior end of a rib is dislocated
onto the costal margin anteriorly, producing a characteristic lancinating type of pain, that may be disabling. It
may mimic other causes of chest or abdominal pain, most notably gall bladder disease when experienced in the right lower ribs. The hooking maneuver can help to confirm the diagnosis. The physician stands at the level of the supine patient’s chest, facing his feet. The inferior costal margin is grasped and the examiner uses his fingers to “hook” under the ribs, applying a cephalad and anterior pressure, looking to reproduce the patient’s symptoms or to feel a popping or clicking sensation.
Sternalis syndrome (A) is a myofascial pain syndrome that causes persistent, mid-chest pain. It is the result of a muscle strain (the inciting cause of which may long be forgotten by the patient), and on examination the clinician will find tenderness to palpation that may cause the pain to radiate bilaterally. The “crowing rooster” maneuver may be used to reproduce the chest pain. The examiner stands behind the patient, who has his elbows bent and arms abducted, while he pulls gentle backward and upward traction on the patient’s elbows, causing stretching of the anterior chest wall. The goal is to reproduce exactly the patient’s symptoms. This maneuver will be positive in many chest wall pain syndromes. (NB: “reproducible chest pain” of course is not pathognomonic for musculoskeltal origin; as we know, reproducible chest pain may occur in up to 10-15% of patients with
ACS)
Although strong and resilient, the fibrous capsules surrounding these joints can fail if enough force or torque is applied through a vector which the joint is not designed to resist. In our patient’s case, the structural integrity of the right 2nd and 3rd sternocostal joints is violated. This is a potentially life-threatening injury, due to the proximity of vital structures: just posterior to the medial third of the clavicle and the sternoclavicular joint lie the innominate artery and vein, vagus and phrenic nerves, internal and anterior jugular veins, trachea, and the esophagus. Immediately posterior to the sternum are the aortic arch, superior vena cava, and right
pulmonary artery.
Treatment of traumatic sternocostal subluxation depends on the stability of the joint. Surgical treatment is
guided by co-injuries identified or by the precariousness of the aforementioned proximal structures. After other
co-injuries are addressed, even grossly unstable joints rarely need surgical intervention: most isolated cases improve with supportive care alone. The goal is to reduce inflammation and allow for the natural sclerosis of the joint.
Tietze syndrome (B) is a benign focal inflammation and swelling of the costosternal joint, often caused by minor
trauma, repetitive motion, chronic cough, or a systemic illness such as viral syndrome. It can affect the
costosternal, sternoclavicular, or costochrondral joints. Tietze syndrome can be readily differentiated from costochondritis by its associated focal swelling and reproducible pain; costochondritis does not present with focal swelling; the pain is reproducible in multiple sites, often in the upper chest. Supportive care with an emphasis on PO fluids and a short course of NSAIDs is indicated.
Slipping rib syndrome (D) – also a diagnosis of exclusion – occurs when the anterior end of a rib is dislocated
onto the costal margin anteriorly, producing a characteristic lancinating type of pain, that may be disabling. It
may mimic other causes of chest or abdominal pain, most notably gall bladder disease when experienced in the right lower ribs. The hooking maneuver can help to confirm the diagnosis. The physician stands at the level of the supine patient’s chest, facing his feet. The inferior costal margin is grasped and the examiner uses his fingers to “hook” under the ribs, applying a cephalad and anterior pressure, looking to reproduce the patient’s symptoms or to feel a popping or clicking sensation.
Sternalis syndrome (A) is a myofascial pain syndrome that causes persistent, mid-chest pain. It is the result of a muscle strain (the inciting cause of which may long be forgotten by the patient), and on examination the clinician will find tenderness to palpation that may cause the pain to radiate bilaterally. The “crowing rooster” maneuver may be used to reproduce the chest pain. The examiner stands behind the patient, who has his elbows bent and arms abducted, while he pulls gentle backward and upward traction on the patient’s elbows, causing stretching of the anterior chest wall. The goal is to reproduce exactly the patient’s symptoms. This maneuver will be positive in many chest wall pain syndromes. (NB: “reproducible chest pain” of course is not pathognomonic for musculoskeltal origin; as we know, reproducible chest pain may occur in up to 10-15% of patients with
ACS)
Sternalis muscle. In: JCB Grant, 1962: An atlas of anatomy by regions.
In our patient’s case, the diagnosis was further delineated by ultrasonography. After a brief observation period, she was discharged home with close follow-up and anticipatory guidance for watchful waiting of resolution of her signs and symptoms over the next several weeks to months.
References
Garretson RB, Williams GR. Clinical evaluation of injuries to the acromioclavicular and sternoclavicular joints. Clin Sports Med. 2003; 22: 239–254.
Lemos MJ, Tolo ET. Complications of the treatment of the acromioclavicular and sternoclavicular joint injuries, including instability. Clin Sports Med. 2003; 22:371–385.
Miller LA. Chest Wall, Lung, and Pleural Space Trauma. Radiol Clin N Am. 2006; 44:213–224.
Mudgal C, Waters PM. Isolated Fracture-Subluxation of the Second Sternocostal Synchondrosis. Amer J Sports Med. 1998; 26(5):729-30.
Rudzki JR, Matava MJ, Paletta GA. Complications of treatment of acromioclavicular and sternoclavicular joint injuries. Clin Sports Med. 2003; 22:387–405.
Special thanks to Dr Amy Dixson and Dr Zachary Soucy for their inspiration and input in this case.
In our patient’s case, the diagnosis was further delineated by ultrasonography. After a brief observation period, she was discharged home with close follow-up and anticipatory guidance for watchful waiting of resolution of her signs and symptoms over the next several weeks to months.
References
Garretson RB, Williams GR. Clinical evaluation of injuries to the acromioclavicular and sternoclavicular joints. Clin Sports Med. 2003; 22: 239–254.
Lemos MJ, Tolo ET. Complications of the treatment of the acromioclavicular and sternoclavicular joint injuries, including instability. Clin Sports Med. 2003; 22:371–385.
Miller LA. Chest Wall, Lung, and Pleural Space Trauma. Radiol Clin N Am. 2006; 44:213–224.
Mudgal C, Waters PM. Isolated Fracture-Subluxation of the Second Sternocostal Synchondrosis. Amer J Sports Med. 1998; 26(5):729-30.
Rudzki JR, Matava MJ, Paletta GA. Complications of treatment of acromioclavicular and sternoclavicular joint injuries. Clin Sports Med. 2003; 22:387–405.
Special thanks to Dr Amy Dixson and Dr Zachary Soucy for their inspiration and input in this case.
