Clinical Orthopedic Imaging

Case Report: Perthes Lesion

Coley C. Gatlin, M.D.; Charles P. Ho, Ph.D., M.D.

Steadman Philippon Research Institute, Vail, CO, USA

History of present illness A 23-year-old female with no signifi- Active range of motion was deferred. Differential diagnosis for cant past medical history sustained Strength testing is 4+/5 with forward anterior glenolabral injuries a traumatic left anterior elevation, abduction, external rota- ­dislocation (1st time) while doing tion, and internal rotation. She has • a back tuck (standing back flip). She 5/5 deltoid strength. The patient had • bony Bankart lesion was able to relocate the dislocation negative provocative testing of the • anterior labroligamentous periosteal on her own after approximately 3 to rotator cuff and acromioclavicular sleeve avulsion (ALPSA) 4 minutes and reported significant . She had positive anterior shoul- • Perthes lesion pain relief after reduction. The injury der apprehension and a positive • glenolabral articular disruption occurred 4 days prior to presenting O’Brien’s test (labral provocative (GLAD) to the orthopedic physician for further testing). • humeral avulsion of the gleno­ evaluation. Since the initial event, humeral (HAGL) she complains of diffuse shoulder Radiographs • bony humeral avulsion of the pain, weakness, and instability. She Left shoulder radiographs demon- ­glenohumeral ligament (BHAGL) reports being unable to lift or reach strated anatomic alignment of the Plan for objects secondary to pain. glenohumeral and acromioclavicular At the patient’s initial presentation, Physical examination with no fracture, bony lesion, or rim avulsion fragments. the treatment options included con- There is no external rash, bruising, servative treatment versus conserva- swelling, deformity, or shoulder girdle Clinical assessment tive therapy and obtaining additional muscle atrophy. Range of motion First-time traumatic anterior shoulder diagnostic imaging studies. After dis- passively is 160 degrees of forward dislocation with resultant anterior cussion with the patient, additional elevation, 90 degrees of abduction, shoulder instability. imaging was performed to assess fur- and 40 degrees of external rotation. ther the degree of injury and inform better the treatment options.

1A 1B 1C

1 Unremarkable left shoulder AP (1A) and axillary (1B) and scapular Y (1C) views radiographs of the left shoulder.

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2A 2B 2 Sequential axial proton density turbo spin echo fat saturation images of the left shoulder from superior to inferior. Sequential MR images extending from superior to inferior along the anterior labrum. The images show labral undermining and partial detachment of the anterior inferior 2C 2D labrum with anterior inferior capsular and periosteal stripping along the anterior inferior glenoid rim and .

MR imaging findings 5. Moderate glenohumeral joint effu- functional stability to the humeral sion with capsular distention, strip- head. This is predominantly due 1. Mild rotator cuff tendinosis. No ping, and and partial tearing to the loss of the normal stabilizing focal . stripping of the anterior shoulder influence of the anterior inferior 2. Undermining and partial detach- capsule along anterior labrum and labrum and inferior glenohumeral ment of the anterior inferior labrum glenoid. ligament. There is little/no displace- with anterior inferior capsular and ment of the labrum, in contrast to periosteal stripping along the ante- Discussion the typical anterior medial capsulo- rior inferior glenoid rim and neck, The Perthes lesion was initially labral and periosteal sleeve displace- with little or no displacement, com- described by a German surgeon ment of the ALPSA lesion. patible with a Bankart lesion and named Georg Clemens Perthes Perthes lesion variant. Radiographic features (1869–1927) in 1905 [1, 3]. The 3. Broad shallow Hill-Sachs impaction injury is an anterior glenohumeral Standard shoulder radiographs may lesion (1–2 mm depth) over about injury in which the anterior labrum be normal or show a Hill Sachs lesion. 3 cm wide area of posterolateral is lifted from the edge of the glenoid humeral head. MR imaging: The Perthes lesion may along with a sleeve of periosteum 4. and possible slight undermin- be demonstrated by fluid extending which is undermined but not torn, ing or partial tearing of the long beneath the labrum and filling the stripped extending medially off the head biceps tendon at the biceps space between the elevated perios- glenoid rim and scapular neck [1]. anchor. teum anteriorly and the scapula Although the labrum may be normally positioned, it no longer provides

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­posteriorly. The labrum is often In one small study, the Perthes lesion Treatment and prognosis ­normally positioned and it may be was best seen on images obtained in difficult to appreciate the lesion the abduction–external rotation posi- Once the diagnosis is made, all especially if scarring obliterates the tion, which allowed visualization of cases are surgically repaired because space deep to the labrum [1, 7]. the labral tear in all patients. On the otherwise the remains The presence of a joint effusion, typi- images obtained for five out of 10 unstable. Typically, these lesions are cally present in more acute injury patients (for three of the five, these repaired via an arthroscopic approach. (as in this patient), or MR arthrogram were MR arthrograms), the tear could During arthroscopic surgery, the (which may be considered in more be seen only in abduction–external Perthes lesion may appear indistin- chronic presentation) may help in the rotation position views [1]. However, guishable from a normal labrum and detection of this lesion [5, 6]. Some the ABER position, by putting abduc- intraoperative probing of the labrum is authors have recommended special tion external rotation traction on the necessary to show the labral detach- positioning of the shoulder joint, spe- anterior to anterior inferior capsulo- ment from the glenoid rim. Therefore, cifically the ABER (abduction-external labral complex, may also tend to the treating surgeon should be aware rotation) position, in cases of ante- reduce the separation and elevation of the MR findings that indicate the rior glenohumeral injury to further of the labrum and periosteum back possibility of a Perthes lesion prior to enhance sensitivity and specificity for to the glenoid margin and perhaps surgery as it may alter surgical treat- the detection of this lesion [4, 6]. then decreasing detection of the ment approach and planning [5, 8]. Perthes lesion.

References 1 Wischer Thorsten K., Miriam A. Bredella, 4 Cvitanic O, Tirman PF, Feller JF, Bost FW, 7 Stoller DW. MR arthrography of the gleno- Harry K. Genant et al. “Perthes Lesion Minter J, Carroll KW. Using abduction humeraljoint. Radiol Clin North Am 1997; (A Variant of the Bankart Lesion): and external rotation of the shoulder to 35:97–116. MR Imaging and MR Arthrographic increase the sensitivity of MR arthrog- 8 Taylor DC, Arciero RA. Pathologic changes Findings with Surgical Correlation.” raphy in revealing tears of the anterior associated with shoulder dislocations: Am. J. Roentgenol. 178, no. 1 glenoid labrum. AJR 1997;169:837–844 arthroscopic and physical examination (January 1, 2002): 233-237. 5 Arciero A, Boone JL. First-time anterior findings in first-time, traumatic anterior 2 Bankart A. The pathology and treatment shoulder dislocations: has the standard dislocations. Am J Sports Med 1997; of recurrent dislocation of the shoulder changed? Br J Sports Med 2010; 25:306 –311. joint. Br J Surg 1938;26:23–29 44:355–360. 3 Perthes G. Ueber operationen bei 6 Waldt S, Burkart A, Imhoff AB, Bruegel M. habitueller schulterluxation. Anterior Shoulder Instability: Accuracy of Dtsch Z Chir 1906;85:199–227 MR Arthrography in the Classification of Anteroinferior Labroligamentous Injuries Radiology November 2005 237:2 578-583

Contact

Charles P. Ho, Ph.D., M.D. Steadman Philippon Research Institute 181 W. Meadow Drive, Suite 1000, Vail, CO 81657, USA [email protected]

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