Brain & NeuroRehabilitation Vol. 4, No. 1, March, 2011 뇌졸중후운동기능의회복단계에따른편마비측어깨통증에대한초음파소견 고려대학교의과대학재활의학교실김낙환ㆍ편성범ㆍ권희규 Ultrasonographic Finding of Painful Hemiplegic Shoulder Associated with Motor Recovery after Stroke Nack-Hwan Kim, M.D., Sung-Bom Pyun, M.D., Ph.D. and Hwee-Kyu Kwon, M.D., Ph.D. Department of Physical Medicine and Rehabilitation, Korea University College of Medicine Objective: To analyze the relationship between painful hemiplegic shoulder (PHS) and ultrasonographic (US) findings according to the motor recovery stage of the stroke. Method: The medical records were reviewed retrospectively in 82 stroke patients from January 2005 to November 2009 who undertook US examination on hemiplegic shoulder. The clinical data collected were age, gender, stroke type, affected side, duration from stroke onset, manual function test (MFT) and the Brunnstrom stage of arm. The presence of spasticity, glenohumeral subluxation and sensory impairment were also investigated. The patients were classified into three groups according to the Brunnstrom recovery stage: the first, second and third recovery stages (RS1, RS2 and RS3). Furthermore, the correlations between US findings and the clinical characteristics according to the Brunnstrom recovery stage were analyzed. Results: The presence of spasticity, glenohumeral subluxation, sensory impairment (proprioception) and MFT scores had statistically significant differences in each group. Among the 82 stroke patients, 62 patients (75.6%) had abnormal findings in US examination. The common abnormal structures were supraspinatus tendon (SST), biceps long head tendon (BLH), subacromial-subdeltoid bursa (SA-SD bursa). The frequencies of total US abnormality in each group were not significantly different (p=0.07). However, the SST abnormality was more frequent in the RS1, and the BLH and SA-SD bursa abnormality were more frequent in the RS3 (p<0.05). Conclusion: In this study, abnormal findings in US examination are frequent in PHS. The abnormal SST is related to the flaccidity, and the abnormal BLH and SA-SD bursa are related to the overuse. (Brain & NeuroRehabilitation 2011; 4: 44-49) Key Words: Brunnstrom recovery stage, painful hemiplegic shoulder, supraspinatus tendon tear, ultrasonography 서론 뇌졸중으로인한편마비환자의어깨통증은비교적흔한합병증으로알려져있으나, 아직그병태생리와정확한치료방법에대해서논란이많은상태이다. 뇌졸중환자의 접수일 : 2010 년 12 월 23 일, 1 차심사일 : 2011 년 1 월 13 일 2 차심사일 : 2011 년 3 월 9 일, 게재승인일 : 2011 년 3 월 10 일교신저자 : 편성범, 서울시성북구안암동 5 가 126-1 136-705, 고려대학교의과대학재활의학교실 Tel: 02-920-6480, Fax: 02-929-9951 E-mail: rmpyun@korea.ac.kr 본연구는 2009 년도정부재원 ( 교육과학기술부인문사회연구역량강화사업비 ) 으로한국학술진흥재단의지원을받아연구되었음 (KRF-2009-32A-H00017). 어깨통증은환자의기능적회복을지연시키고일상생활의기본동작수행에도많은제한을가져와치료의효율성과삶의질을저하시키는커다란요인으로작용할수있다. 1 근골격계의초음파검사는비침습적이고임상에서간단하게시행할수있으며, 검사비용이비교적저렴하다는장점이있다. 어깨부위의통증에대한초음파검사의유용성은견봉하증후군 (subacromial syndrome) 의경우진단의정확도가 94.9% 로높은것으로보고되었으며, 2 van Moppes 등 3 은통증을동반한회전근개손상환자에서초음파검사의민감도는 86%, 특이도는 91% 로선별진단검사로서가치가높다고보고하였다. 편마비환자의어깨통증의원인은전하방부분탈구, 회전근개및이두근의질 44
김낙환 외 2인 뇌졸중 후 운동기능의 회복 단계에 따른 편마비측 어깨 통증에 대한 초음파 소견 환, 경직, 관절낭의 구축, 복합부위통증증후군 등으로 알 환자를 대상으로 Brunnstrom 기에 따른 단계별 어깨관절 려져 있는데,4 이에 대해 회전근 건염, 회전근 건의 파열, 초음파 소견과 다양한 임상 양상들과의 관계를 분석하여 관절내 삼출 등 초음파 검사를 통해 평가할 수 있는 병리 관련성을 제시하고자 한다. 소견들이 제시되어왔다. 그러나 아직 뇌졸중 이후 회복 단 계에 따른 편마비측 어깨 관절의 초음파 검사 소견과 임상 연구대상 및 방법 양상에 대한 연구는 많지 않은 형편이다. 본 연구는 뇌졸중 환자에서 어깨 통증을 동반한 편마비 후향적 의무기록 조사를 시행하여 2005년 1월부터 Fig. 1. Abnormal ultrasonographic finding of hemiplegic shoulders. The arrowheads indicate the abnormal lesions. The partial-thickness tear in supraspinatus tendon was noted on longitudinal view (A) and transverse view (B), and the full-thickness tear on longitudinal view (C). The fluidfilled defect was noted in sheath of biceps long head tendon on transverse view (D). The focal hypoechoic defect in subscapularis on transverse view (E). The fluid-filled defect was noted in the subacromial-subdeltoid bursa area (F). 45
Brain& NeuroRehabilitation:2011; 4: 44~49 2009년 12월까지허혈성및출혈성뇌졸중으로본원에입원한편마비환자중편마비측어깨통증으로초음파를시행한 82명을대상으로하였다. 어깨관절의질환이나손상의과거력혹은수술력이있는경우는제외하였다. 기본정보로연령, 성별, 당뇨병의이환유무, 뇌졸중발생과초음파검사시점사이의기간, 뇌졸중의유형및편마비측위치를조사하였고, Brunnstrom 기, 뇌졸중상지기능평가 (Manual function test, MFT) 점수를기록하였으며, 감각이상, 경직, 어깨부분탈구의유무를조사하였다. 뇌졸중후기능적회복에대한기준은 Brunnstrom 기 5 를이용하여, 1 2기는 1차회복단계 (first recovery stage, RS1), 3 4기는 2차회복단계 (second recovery stage, RS2), 5 6기는 3차회복단계 (third recovery stage, RS3) 로분류하였다. MFT는뇌졸중환자에서전반적인상지기능을평가하는검사로어깨의큰움직임부터손의미세운동능력까지 8개평가항목으로구성되어있으며, 6 이는수년간의임상경력을지닌작업치료사 2인에의해평가되었다. 감각의평가는편마비측상지의촉각 (light touch), 통각 (pin-prick), 위치감각 (proprioception) 을조사하였고, 촉각과통각은표층감각 (superficial sensation) 으로, 위치감각은심부감각 (deep sensation) 으로분류하여이상유무를조사하였다. 어깨경직은 modified Ashworth scale 7 을이용하여 1점이상일경우경직이존재하는것으로정하였다. 8 어깨부분탈구는침상에서수지폭검사를이용하여견봉하연과상완골두사이간극을손가락넓이의단위로표현하여측정된것으로최소한 1개수지폭이상인경우에어깨부분탈구가존재하는것으로정하였다. 모든환자는편마비측어깨통증을호소하는당일에 7 15 MHz 주파수의고해상선형탐침 (EnVisor HD system, Phillips, Bothell, USA) 으로초음파검사를시행받았다. 초음파검사소견중극상근건 (supraspinatus tendon, SST) 의이상소견은건이보이지않거나파열의범위가관절면에서활 액낭면까지확장되어비연속성이힘줄의모든층에서관찰되는경우 (full-thickness tear) 와복합성에코가있거나저에코의부위가최소한 2개의교차면에서보이는경우 (partial thickness tear) 로정하였다. 9 상완이두근건 (Biceps long head tendon, BLH) 의이상소견은, 횡단면상건주위의저에코륜소견을보이거나종단면상건주위저에코륜을보이고팔의움직임에따라삼출액의이동이나타나는소견으로정하였다. 10 견봉하 -삼각근하윤활낭 (Subacromialsubdeltoid bursa, SA-SD bursa) 의이상소견은, 윤활낭두께가 2 mm 이상이면서삼출액저류로인한저에코가관찰되거나활액막의증식에따른고에코가관찰되는경우로정하였다. 11 견갑하근 (subscapularis tendon, SCT) 의이상소견은, 상완을외회전시킨상태에서검사를시행하여복합성또는저에코성병변이다양한각도에서확인되거나힘줄의비연속성이나타날때로정하였다 (Fig. 1). 12 자료는 SPSS 통계프로그램을이용하여분석하였다. RS1, RS2, RS3군들의임상양상과초음파소견의연관성을파악하기위해카이제곱검정법과분산분석법및 t 검정법을이용하였고, 각군의비정상초음파소견들의빈도를비교하기위해 Fisher의정확검정법을이용하였다. 통계적유의성은 p<0.05 수준으로하였다. 결과 환자들의성별은남자 37명, 여자 45명이었고, 평균연령은 63.5세 ( 범위 : 41 85세 ) 이었다. 뇌졸중의유형은출혈성 52명, 허혈성 30명이었고, 편마비측은오른쪽 33명, 왼쪽 49명이었다. RS1, RS2, RS3 환자군의기본정보를비교하였을때유의한차이를보이지않았다 (Table 1). 경직은 RS2 군에서, 어깨부분탈구는 RS1와 RS2 군에서다른군에비해유의하게많은빈도를보였고, 표층감각의이상은통계적으로유의한차이가없는반면, 심부감각 Table 1. Group Comparison of Clinical Characteristics in Patients with Stroke RS1 (n = 48) RS2 (n = 21) RS3 (n = 13) p value Age, years, mean (SD) Gender, male/female Diabetes mellitus (%) Stroke type (%) Infarction Hemorrhage Hemiplegic side, right/left Duration from stroke onset, days, mean (SD) 63.5 (10.7) 24/24 10 (20.8) 19 (39.6) 29 (60.4) 21/27 41.9 (24.1) 63.6 (13.2) 10/11 6 (28.6) 7 (33.3) 14 (66.7) 6/15 46.2 (30.5) 63.1 (4.1) 3/10 2 (15.4) 4 (30.8) 9 (69.2) 6/7 47.2 (15.5) 0.99 0.22 0.64 0.89 0.44 0.70 SD: standard deviation, RS1: first recovery stage (Brunnstrom stage 1, 2), RS2: second recovery stage (Brunnstrom stage 3, 4), RS3: third recovery stage (Brunnstrom stage 5, 6). 46
김낙환외 2 인 : 뇌졸중후운동기능의회복단계에따른편마비측어깨통증에대한초음파소견 Table 2. Physical Findings According to the Stage of Motor Recovery RS1 (n = 48) RS2 (n = 21) RS3 (n = 13) p value Spasticity of shoulder (%) Glenohumeral subluxation (%) Sensory impairment Superficial sensation (%) Deep sensation (%) MFT scores, mean (SD) 18 (37.5) 33 (68.8) 36 (75.0) 34 (70.8) 2.3 (4.4) 15 (71.4) 11 (52.4) 15 (71.4) 11 (52.4) 14.3 (5.7) 3 (23.1) 1 (7.7) 6 (46.2) 3 (23.1) 21.8 (2.5) 0.02* <0.01* 0.13 0.01* <0.01* *p<0.05. SD: standard deviation, RS1: first recovery stage (Brunnstrom stage 1, 2), RS2: second recovery stage (Brunnstrom stage 3, 4), RS3: third recovery stage (Brunnstrom stage 5, 6), MFT: manual function test. Table 3. Group Analysis for Abnormal Ultrasonographic Finding Abnormal US findings RS1 (n = 48) RS2 (n = 21) RS3 (n = 13) p BLH (%) SST (%) SCT (%) SA-SD bursa (%) Total (%) 12 (25.0) 28 (58.3) 2 (4.2) 15 (31.3) 39 (81.3) 7 (33.3) 5 (23.8) 0 (0.0) 6 (28.6) 12 (57.1) 8 (61.5) 4 (30.8) 1 (7.7) 10 (76.9) 11 (84.6) 0.04* 0.02* 0.61 0.01* 0.07 *p<0.05. US: ultrasonographic, RS1: first recovery stage (Brunnstrom stage 1, 2), RS2: second recovery stage (Brunnstrom stage 3, 4), RS3: third recovery stage (Brunnstrom stage 5, 6), BLH: biceps long head, SST: supraspinatus tendon, SCT: subscapularis tendon, SA-SD: subacromial-subdeltoid. Table 4. The Relationship between Clinical Features and Abnormal Ultrasonographic Findings Relative risk or p-value (95% CI) SST BLH SA-SD bursa Shoulder spasticity Glenohumeral subluxation Impaired deep sensation MFT scores 0.41 (0.26 0.64)* 3.00 (1.86 4.81)* 2.56 (1.68 3.91)* p=0.08 0.85 (0.63 1.15) 0.87 (0.63 1.20) 0.87 (0.63 1.20) p=0.41 0.86 (0.61 1.20) 1.17 (0.84 1.64) 1.35 (0.96 1.94) p=0.04*, *p<0.05. The MFT scores of group with SA-SD bursa abnormality were significantly higher than those with normal SA-SD bursa. CI: confidence interval (upper-lower), SST: supraspinatus tendon, BLH: biceps long head tendon, SA-SD: subacromial-subdeltoid, MFT: manual function test. 의이상은통계적으로유의한차이를보였고, MFT 값또한유의한차이를나타내었다 (Table 2). 초음파검사에서, 82명의환자중 62명 (75.6%) 에서이상소견이나타났다. 각환자군의초음파이상소견의빈도는통계적으로유의한차이를보이지않았으나 (p=0.07), 이상소견을보인구조물중에서 BLH와 SA-SD bursa는 RS3 군에서, SST는 RS1 군에서유의하게많은빈도를보였다 (Table 3). 상기결과들을바탕으로어깨경직, 어깨부분탈구, 심부감각의이상, MFT 값들이초음파검사의이상소견들에미치는비교위험도와관련성을통계적인방법을이용하 여산출하였다. 어깨경직이없는경우와어깨부분탈구와심부감각의이상이있는경우에각각 SST의이상소견에유의한위험도를나타내었고, SA-SD 윤활낭의이상소견을보이는군의 MFT 값은이상소견을보이지않는군의 MFT 값에비해의미있게높았다 (p<0.05) (Table 4). 고찰 편마비측어깨통증은뇌졸중후주요합병증중에하나이며, 마비및경직이동반된경우정상인의어깨통증과달리객관적인신체검진이어려운특징을지닌다. 13 어깨 47
Brain& NeuroRehabilitation:2011; 4: 44~49 관절초음파검사는간편하고통증을거의일으키지않는시술로서통증과관련된병리소견을제시하여진단과치료에도움을주어, 14 뇌졸중후편마비측어깨통증을평가하는데유용하다. 김등 15 은편마비측어깨통증을호소하는 20명의환자를대상으로초음파검사상관절내삼출이어깨통증과관련이있음을제시하였고, 고등 16 은통증을동반한편마비측어깨의초음파상이상소견의빈도 (51.0%) 가통증을동반하지않는군 (9.5%) 에비해의미있게높은것을보고하였다. 3주정도의기간을두고추적검사를시행한다른연구에서는통증과관련된편마비측어깨의초음파이상소견의빈도를 55.9 85.3% 로보고하였다. 17 본연구에서편마비환자중어깨관절통증을호소하는 82명의환자를대상으로초음파검사를시행한결과 62명 (75.6%) 에서이상소견이관찰되어앞선연구들과비슷한결과를보였다. MFT는뇌졸중후편마비측상지의손상된운동기능의수준을잘반영하고 Brunnstrom 기와유의한관련이있음이밝혀져있다. 18 본연구에서극상근건의이상소견은회복의초기단계에상대적으로높은빈도를보였는데, 이는 RS1 환자군에이완성 (flaccid) 어깨의빈도가많기때문인것으로해석된다. 과거연구들은이완성편마비측상지가경직이있는경우보다회전근개의손상에더취약한것으로보고하였다. 그원인으로반복적인신장손상과어깨이음근육들 (shoulder girdle muscles) 의취약해진보호기능때문으로설명하였으며, 19,20 뇌졸중후편마비측의손상된회전근개에대한자세한신체검진결과극상근건이상소견의빈도 (48%) 가가장많다고보고하였다. 21 이와관련하여본연구에서 RS1 환자군에는어깨부분탈구의빈도가 68.8% 로다른군에비해상대적으로많았고, 어깨부분탈구있는군은없는군에비해극상근건의손상을보일수있는비교위험도가 3배정도인결과를보였다. 또한심부감각의이상또한회전근개손상의위험요소로분석되었는데, Chang 등 22 은촉각 (tactile) 의이상이어깨부분탈구의관련요인이라주장하였고, Huang 등 17 은고유수용감각 (proprioception) 의이상이편마비측어깨의연부조직손상및통증과관련이있음을밝힌바있다. 상완이두근건의이상은편마비측어깨에서통증을유발하는원인으로알려져있다. 21 정상인에서상완이두근건의어깨관절에대한기능이명확히밝혀지지않았지만, 일반적으로어깨관절 (glenohumeral joint) 의수직적안정성에기여하는것으로받아들여지고있다. 일부연구들에서어깨관절이불안정할수록상완이두근의역할이증가하고, 23 극상근건파열로인한상완이두근건의과부하가병리기전이라고주장하였다. 24 본연구에서총 27명 (32.9%) 의환자에서상완이두근건의이상소견을보였는데, Brunnstrom stage 5 6기의환자군에서상대적으로많은빈도 (61.5%) 를보였으며이들중절반이극상근건의손상을동반하고있었다. 반면반수이상 (58.3%) 이극상근건손상을보인 RS1 군에서는상완이두근건의이상소견이 25.0% 에불과하였다. 이등 25 의연구에서도 Brunnstrom stage 5 6기의환자군에서상완이두근의이상소견이다른이상소견에비해많았다. 즉, 편마비측어깨의상완이두근건이상은, 앞서언급한정상인에서의병리기전뿐만아니라어깨근육들의상대적인운동기능회복차이와관련을가지거나불완전하게회복된운동기능으로인한불안정성어깨움직임이과도하게증가하여발생한것으로생각된다. 25 더욱이 RS3 환자군에서견봉하-삼각근하윤활낭의이상소견의빈도가높고, MFT 값이윤활낭의이상유무와유의한관련성 (p=0.02) 을가진결과도불안정성과과사용 (overuse) 을뒷받침하는소견으로생각된다. 본연구의제한점으로, 후향적으로자료를수집함에따라통증이나경직의정도를파악하지못하여정량화를시행하지못했다는점과통증을호소하지않는편마비환자군과비교하지못한점을들수있다. 게다가초음파상의병리적소견들의시간적전후관계를규명하지못한단면조사의한계로인해, 이러한이상소견들이통증발생에기여할뿐근본적인원인으로제시될수는없을것으로사료된다. 이를위해향후잘계획된비교연구가추가적으로필요할것으로생각된다. 결론 뇌졸중발생이후편마비측어깨관절에통증을호소하는환자에서초음파검사상이상소견을보인경우가 75.6% 로매우흔하였으며, 이중극상근건, 상완이두근건, 견봉하-삼각근하윤활낭의이상소견이가장많았다. 초음파상이상소견의빈도는운동기능의회복단계와통계적인관련이적지만, 이상을보이는세부구조물의빈도는단계에따른차이를보여, 극상근건의이상소견은 Brunstrom stage 1 2에서, 상완이두근건과견봉하-삼각근하윤활낭의이상은 Brunnstrom stage 5 6에서상대적으로높은빈도를나타내었다. 이는각각이완성마비로인한극상근건의반복적인과신장손상과, 손상이후이차적인상완이두근건의과부하와불안정한어깨관절의과사용이원인으로작용했을가능성이있어편마비측상지의재활치료에주의가필요할것으로생각된다. 48
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