Link to related CJSM article: ts Frequency_and.5.

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1 Link to related CJSM article: ts Frequency_and.5.aspx Link to related case: Case #3: Wrist pain after a fall Author: Christopher Huckle, DO CJSM Series Editor: Michael Henehan, DO AMSSM Editor: Charlie Michaudet, MD AMSSM Senior Editor: Meg Gibson, MD Presentation Intense pain and decreased function in the left hand/wrist History A 29 y/o white male who had a dirt biking accident two days prior to presentation at the Emergency Department. He was initially seen at a local Urgent Care where one X-ray was taken and he was told he had a "simple fracture". He then had a splint placed and was told to follow up with either his PCP or an Orthopedic physician, however the patient did not have insurance or any source of income. The next day, the day of presentation, he woke up with increasing pain, swelling, and noticed "a weird feeling" in his hand which was not present the day prior. When he presented to the ER, 18 hours after initially visiting the Urgent Care, he was complaining of extreme and increasing wrist pain, restricted motion and new onset numbness in all of his fingers of his left hand. When asked, he is unsure exactly how he fell on his hand but knows he was going at least 45mph when he fell and he tried using his hands to brace his fall. Physical Exam GENERAL - Well developed, well nourished, young white male who is sitting up in bed, guarding his left wrist, appearing in moderate distress HEENT - Normocephalic, atraumatic CARDIO - Tachycardic, S1 and S2 audible; 2+ pulse palpated of the left wrist. Sluggish capillary refill time (>3 seconds) of the digits of the left hand PULM - Clear to auscultation bilaterally SKIN - Dorsal swelling of the left wrist; Digits of the left hand appeared mottled. Digits of the left hand are cool to touch comparatively to digits of the right hand MSK - Tender to palpation over the carpus, but not over the metacarpals or the digits. Range of motion was limited by pain both actively and passively, however patient was observed flexing and extending it on his own. 2/5 grip strength appreciated NEURO - Sensation to light touch preserved of the left hand. Digits in median distribution had decreased sensation.

2 Challenge Question #1 If you were the urgent care physician initially evaluating this patient, which symptoms would prompt you to recommend an immediate orthopedic consultation? a) Pain b) Swelling c) Decreased sensation or pulses d) Pallor Broad Diagnosis 1) Left Scaphoid Fracture 2) Compartment Syndrome of the Wrist 3) Median Nerve Stretch Injury 4) Perilunate Dislocation 5) Lunate Dislocation 6) Left Wrist Sprain Labs- None Other Studies X-rays: PA and Lateral Challenge Question #2 True or False? The PA image is the best x-ray view to evaluate for a perilunate dislocation. (CJSM Editor s Note: What to look for in the images. On the PA image you can see the loss of Gilula s Arcs/Lines and on the lateral image you can see the dislocation of the capitate while the lunate articulation with the radius is maintained)

3 Consultations Orthopedic Surgery Working Diagnosis Trans-Scaphoid Perilunate Dislocation Treatment Once the diagnosis of a Perilunate dislocation was made, and with the patient's presenting/worsening symptoms, it was decided that a closed reduction would be needed. Consent was given by the patient and he was sedated with 38mg of Etomidate, 50mcg of Fentanyl and 4mg of Morphine. The injured hand was then placed in finger straps and the elbow was placed at a 90-degree angle. On the distal part of the arm, the patient had 6lbs of

4 traction and this was applied for minutes. The wrist was then placed into extension with more traction applied followed quickly by flexion of the wrist. The patient felt immediate relief and an X-ray was taken to confirm proper reduction of the lunate. A sugar tong splint was applied with the wrist in 10 degrees of flexion and a slight radial deviation. Outcome The patient was able to tolerate the procedure well. He was told to follow-up at the Orthopedic clinic the next day and was referred to a hand surgeon for open reduction with ligament repair fixation with possible carpal tunnel release. Unfortunately, the patient was lost to follow-up Author s Comments Usually the mechanism of injury of a high velocity trauma onto a dorsiflexed wrist that has been deviated in an ulnar direction is the most common cause of perilunate dislocations and perilunate fracture dislocations. Unfortunately, these injuries are often missed on initial presentation. Wrist dislocations only account for < 10% of all wrist injuries. According to Mayfield et.al. there are four stages to describe a lunate instability: 1) Scapholunate dissociation or rotatory subluxation of the scaphoid 2) Perilunate dislocation commonly with scaphoid fractures 3) Midcarpal Dislocation usually with a triquetral fracture and 4) Lunate Dislocation. In the case of a Lunate dislocation, the scapholunate ligament is disrupted, followed by disruption of the capitolunate articulation and lunotriquetral articulation and the lunate will rotate into the carpal tunnel causing median nerve damage

5 It is important that even after closed reduction, the patient have ORIF. Patients who were operated on earlier than 5 months showed greater overall outcome with quicker return to activity. However, depending on the level of competition, even after the open reduction there is no guarantee the athlete will return to his pre-injury level. Editor s Comments The author highlighted very well that those injuries are often missed initially. Radiographic evaluation is the key. The wrist PA view is useful as it enables to assess the Gilula lines, which are imaginary lines drawn across the proximal and distal aspects of the proximal carpal row and the proximal aspect of the distal carpal row. These lines should appear as 3 smooth arcs running nearly parallel to each other. Any disruption of these lines supports carpal incongruity. The wrist lateral view is the most important. Any disruption of the collinearity of the radius, lunate and capitate suggests a perilunate dislocation. The presence of tingling or numbness in the median nerve distribution or acute carpal tunnel syndrome should prompt emergent close reduction, but if symptoms persist despite close reduction, emergent open reduction should be performed. Close reduction with sedation followed by open fixation within a few days is preferred to close reduction and casting. Even with optimal treatment, about 70% of patient will develop complications such as wrist stiffness, diminished grip strength, and post-traumatic arthritis but are often well tolerated. Challenge Question #3 The difference between a lunate and perilunate dislocation can best be described as: a) In a lunate dislocation, the articulation between the lunate and the radius is preserved, but the articulation between the capitate and the lunate is disrupted b) In a lunate dislocation, the articulation between the lunate and the radius is disrupted, but the articulation between the capitate and lunate and is preserved c) In a lunate dislocation, the articulation between the lunate and the radius is disrupted as well as the articulation between the capitate and lunate d) In a lunate dislocation, the articulation between the lunate and radius is preserved as well as the articulation between the capitate and lunate References 1) Mayfield JK, Johnson RP, Kilcoyne RK. Carpal Dislocations: pathomechanics and progressive perilunar instability. J Hand Surg AM. 1980;5 (3): ) Jebson PJ, Engber WD. Chronic perilunate fracture dislocations and primary proximal row carpectomy. Iowa Orthop J. 1994:14:42:42-8 3) Pappas ND, Lee DH. Perilunate injuries. Am J Orthop (Belle Mead NJ) Sep;44(9):E Challenge question answers: 1) Answer: C & D. Pain and swelling are concerning symptoms with orthopedic injuries and certainly warrant evaluation and possible imaging, but decreased sensation, decreased

6 pulses and tissue pallor indicate possible neurovascular compromise and should ideally be evaluated and treated by an orthopedic surgeon within hours to help avoid permanent tissue damage. 2) Answer: False. Both views are important, but the lateral image usually gives the best view to determine the position of the lunate relative to the radius. 3) Answer: C. The distinguishing imaging characteristic between a lunate and perilunate dislocation is the position of the lunate relative to the radius. In a lunate dislocation, the lunate is disarticulated in from the radius and usually tipped forward in a volar direction ( Tea cup tipped on its side ). In a perilunate dislocation the lunate maintains its normal position relative to the radius ( tea cup in an upright position ). In both instances, the articulation between the lunate and the capitate is disrupted.