대한족부족관절학회지 : 제 11 권제 1 호 2007 J Korean Foot Ankle Soc. Vol. 11. No. 1. pp.8-12, 2007 인제대학교의과대학서울백병원정형외과학교실 The Height and Volume of Medial Longitudinal Arch in Normal and Painful Feet Woo-Chun Lee, M.D., Jeong-Seok Moon, M.D. Department of Orthopedic Surgery, Seoul Paik Hospital, College of Medicine, Inje University, Seoul, Korea =Abstract= Purpose: The purpose of this study was to investigate the differences in simple radiographic parameters and results of 3-D scan among normal and patient groups. Materials and Methods: Seventy subjects in each group were studied. Control group consisted of subjects without plantar foot pain (normal group), and two patient groups were one with plantar forefoot pain (metatarsalgia group), the other with plantar heel pain (heel pain group). Simple radiographic parameters were obtained and 3-D scan was done with foot scanner (Nexscan, K&I, Korea) and The height and volumn of the space under the medial longitudinal arch was analyzed (Enfoot, K&I, Korea). These parameters were compared and correlation between radiological parameters and results of the 3-D scan were studied. Results: The results of all parameters distributed normally. There was no signigicant differences among the groups in radiological parameters (talo-first metatarsal angle, calcaneal pitch angle and height of the talar head in standing lateral radiograph) and arch height and arch volumn on 3-D scan. There were statistically significant correlations between radiological and 3-D scan results. Conclusion: This study revealed that there is no significant differences in medial longitudinal arch height and volumn among normal and different patient groups and there are variety of arch height in patients with similar symptoms. Key Words: Foot, Medial longitudinal arch, Metatarsalgia, Heel pain, 3-D scan 서 론 발에있는내측종아치의높이를판단하기위한방사선 학적인지표들에는거골-제1 중족골간각도, 종골피치각 도등이있다. 이런지표들이일정한범위를벗어나는경우 Address for correspondence Woo-Chun Lee, M.D. Seoul Paik Hospital, College of Medicine, Inje University, 82 Jeo-dong, Jung-gu, Department of Orthopaedic Surgery 100-032, Seoul Tel: +82-2-2270-0042 Fax: +82-2-2270-0264 E-mail: wclee@seoulpaik.ac.kr 를편평족또는요족이라고하며, 치료전후의변형의변화정도를이런지표를이용하여표현한다. 그러나상당수의발통증환자의발은편평족이나요족이라는변형의범주에포함될정도로심한아치의이상소견을보이지않는데, 단순방사선상에서는발의아치모양이비슷하더라도후족부가외반또는내반됨에따라서발의형태의상당한변화 - 8 -
Figure 1. S tan ding l ateral radiogra ph s how in g ta lar head height (A) and arch length (B). 가있을가능성이있으며, 평면상의측정치로실제의발의형태를유추하는데는한계가있을것으로사료된다. 단순방사선상의지표들이아닌아치를판단하는다른방법중에서아치부분의공간의부피가질환을판단하고, 깔창제작에응용할수있는가능성이있을것이라는가정하에본연구를시작하였다. 또한단순방사선상의지표들과발을 3차원스캔한결과를비교하여보면발의형태에대한어떤새로운인식이가능할것으로판단하였다. 저자들은단순방사선상의지표들과 3차원적인스캔을이용한측정결과가정상인과발바닥통증이있는환자군에서차이가있는가를알아보기위하여본연구를하였다. 대상및방법 발바닥의통증이없는대조군 ( 이하정상군이라고함 ) 70명, 전족부바닥에통증이있는환자 ( 이하중족골통증군이라고함 ) 70명, 뒤꿈치족저부에통증이있는환자 ( 이 하뒤꿈치통증군이라고함 ) 70명을대상으로하였다. 단순방사선상의지표들을측정하고, 발을삼차원발스캐너 (Nexscan, K&I, Korea) 를이용하여스캔한후에분석프로그램 (Enfoot, K&I, Korea) 을이용하여삼차원공간을분석하였다. 정상군과양측또는우측에만증상이있는대상자는우측족부를대상으로하였으며, 좌측족부에만통증이있는환자는좌측을대상으로하였다. 단순방사선상의지표로는측면방사선상에서거골-제1 중족골간각도, 종골피치각도를측정하고, 아치비율을구하였다. 아치비율은저자들이아치의높이를판단하기위한지표로고안한것인데거골두의가장하방을아치의가장높은점으로하고바닥에서거골두의하방까지의거리를거골두높이라고하였다. 거골두높이의실측치가발크기방사선촬영시에발생하는확대에의한오차가발생하지않도록하기위하여거골두높이를아치길이 ( 제1중족골두의가장원위단에서종골의가장후방까지의거리 ) 로나눈값을아치비율이라고하였다 (Fig. 1). 각각의각도와길이는같은사람이두번측정한것의평균치로하였다. 검사하는발에는체중부하를하지않고발을바닥에대면족저부의대부분이바닥에닿으며내측종아치아래부분에만공간이발생하는데이곳을내측종아치공간이라고하였다 (Fig. 2). 내측종아치부분의공간은하방과상방, 외측은경계가있으나내측은경계가없으므로제1 중족골두내측의가장돌출된부분과뒤꿈치내측의가장돌출된부분을잇는선에서지면에수직인면을세웠다고가상하여내측한계를설정한후에막힌공간을만든후에부피를측정하였는데, 이가상면이상방으로연장되면서발에막히지않고허공으로연장되어서막힌공간을설정할수가없는경우가있었다. 그래서이가상면을외측으로 5 mm 와 10 mm 이동한면을가상하고그면에의하여형성 ( A ) ( B ) Figure 2. Oblique (A) and lateral (B) Images of three dimensional foot scan showing medial longitudinal arch( ). - 9 -
였다. 또한단순방사선상거골-제1 중족골간각도와거골두높이, 그리고삼차원스캔상의아치높이사이의 Pearson 상관계수를구하였다. 통계프로그램은 Medcalc version 8.0 (Medcalc Softwear, Mariakerke, Belgium) 을사용하였다. 결 과 ( A ) ( B ) Figure 3. A photograph of foot showing that a perpendicular plane to the floor along the line which connects the medial surface of the first metatarsal head and the heel does not touch the medial surface of the foot (A) and a plane 5 mm lateral to this plane touches the medial surface of the foot to make a closed space under the medial longitudinal arch (B). 되는내측종아치공간의부피를측정하였으며, 각각을 5 mm 아치공간, 10 mm 아치공간이라고하였다 (Fig. 3). 이와같이형성된내측종아치공간에서수직높이가가장높은부분을아치높이라고하였으며각각 5 mm 아치높이, 10 mm 아치높이라고하였다. 아치높이는발길이 170 cm로표준화하기위하여아치높이 170/ 환자의발길이를구하여비교하였다. 정상군과전족부통증군, 뒤꿈치통증군사이에각각의지표들에유의한차이가있는가를단변량분산분석 (one way ANOVA) 검사를하였으며유의수준은 p=0.05로하 단순방사선상의모든계측치와 3차원스캔상의계측치들이정규분포를하였다. 단순방사선상에서거골-제1 중족골간각도는정상군에서평균 -3.6±5.56도, 중족골통증군에서 -2.1±5.17 도, 뒤꿈치통증군에서 -2.2±5.68 도이었으며각군간에유의한차이가없었다. 단순방사선상에서종골피치각은정상군에서평균 16.7 ±5.10도, 중족골통증군에서평균 17.1±4.58도, 뒤꿈치통증군에서평균 17.3±3.99 도이었으며각군간에유의한차이가없었다. 단순방사선상에서아치비율은세군에서모두평균 0.3±0.03 이었으며각군간에유의한차이가없었다. 삼차원스캔상에서 5 mm 아치높이는정상군에서평균 15.8±6.68 mm, 중족골통증군에서 14.2±6.39 mm, 뒤꿈치통증군에서 14.5±5.84 mm이었으며 10 mm 외측의아치높이는정상군에서평균 11.6±5.65 mm, 중족골통증군에서 9.6±5.18 mm, 뒤꿈치통증군에서 9.6±5.07 mm 이었다 (Table 1). 5 mm 아치공간은정상군에서평균 8.6±5.96 cm 3, 중족골통증군에서에서 6.8±4.38 cm 3, 뒤꿈치통증군에서 7.2±4.58 cm 3 이었고, 10 mm 아치공간은정상군에서평균 4.2±4.00 cm 3, 중족골통증군에서 Ta b l e 1. Arch Volume and Arch Height at 5 mm and 10 mm Medial to the Insid e J oin t L ine Arch V5* (mm 3 ) Arch H5 (mm) Arch V10 (mm 3 ) Arch H10 (mm) No pain 8.6 15.8 4.2 11.6 Metatarsalgia 6.8 14.2 3.1 9.6 Heel pain 7.2 14.5 3.5 9.6 No pain, control subjects with no foot pain; metatarsalgia, patients with plantar forefoot pain; heel pain, patient with heel pain. *Arch V5, the volume of a space under the medial longitudinal arch formed by a plane which passes 5 mm lateral to the line connecting the medial surface of the first metatarsal head and the heel; Arch H5, the height of a space under the medial longitudinal arch formed by a plane which passes 5 mm lateral to the line connecting the medial surface of the first metatarsal head and the heel; Arch V10, the volume of a space under the medial longitudinal arch formed by a plane which passes 10 mm lateral to the line connecting the medial surface of the first metatarsal head and the heel; Arch H10, the height of a space under the medial longitudinal arch formed by a plane which passes 10 mm lateral to the line connecting the medial surface of the first metatarsal head and the heel. - 10 -
에서 3.1±2.70 cm 3, 뒤꿈치통증군에서 3.5±2.81 cm 3 이었고각군간에유의한차이가없었다. 단순방사선상의거골-제1 중족골간각도와아치비율, 5 mm 아치높이, 10 mm 아치높이사이에는통계적으로유의한상관관계가있었다 (P<0.001) 고찰발을 3차원적으로측정하기위한방법으로 Bergmann 스캐너 2), AMFIT 시스템 4) 등이있으며, 3차원전산화단층촬영을이용하는방법 10) 도보고되어있다. 본연구에사용된스캐너는 3D vision 을이용한형상복원방식을바탕으로발및화형 (last) 의삼차원모델을자동으로생성해주는데, 측정대상의표면에반사된레이저슬릿광을 CCD (charge coupled device) 카메라로촬영하고이를이용하여삼차원정보를복원하는방식이다 4). 본연구에서다른지표들을제외하고내측종아치공간의부피를구한이유는발바닥이지면에닿으면다른부분들은전부바닥면에접촉하여평평한면을이루고내측종아치의아래부분만바닥으로부터분리되어공간을형성하기때문이다. 체중의 1/2 만큼체중부하를하여연구한보고 3,5) 가있으나체중부하를하면내측종아치부분마저바닥면과완전히접촉하여부피측정이불가능한예들이많아서체중부하를하지않은상태에서스캔한측정치를이용하여부피를구하였다. 스캔상에서아치의근위단, 원위단, 외측단등의여러가지지표를측정할수도있을것이지만여러가지오차의가능성이있으며 3), 부피만측정하면높이이외에종방향과횡방향의길이가미치는영향을종합적으로판단할수있기때문에가장뚜렷한지표인높이와부피만을측정하였다. 방사선학적인방법으로아치를측정할경우에는뼈를기준으로아치의높낮이를판단하지만표면을 3차원스캔한결과는뼈와연부조직을포함한외형상의아치의높낮이와전체적인공간의부피를측정할수있다는차이점이있다. 본연구에서단순방사선상의지표들인거골-제1 중족골간각과아치비율, 그리고삼차원스캔상의아치높이사이에는강한상관관계를나타내어서단순방사선상의지표만으로도아치부피를상당히반영할수있다고할수있을것이다. 또한삼차원스캔상에서 5 mm 아치높이와 10 mm 아치높이는상관계수가 0.92 로서어느평면을이용하거나거의같은의미가있을것이다. 환자군과정상군사이에본연구의지표들이차이가있는가를연구하는이유는발바닥의어떤특정부위의통증이 있는환자가어떤발형태를가지는경향성을파악하여신발과깔창제작에참고하려는의미도있다. 발바닥의압력과각종방사선학적인지표들과관절운동각도들과같은계측가능한측정치들을모두종합하여도족저압력을 50% 밖에예측할수없다는보고 8) 가있지만, 저자들은아치가높으면바닥면과접촉하는면적이좁아서단위면적당의압력이증가하므로전족부통증등과연관성이있을가능성이있어서이연구를하였다. 높이와부피가통증부위에따라서차이가있다면환자에게깔창을만들어줄때아치부분의높이와부피를통증부위에따라서다르게만들어야한다는근거가될수있다고생각하였고, 중족골통증이있는환자군에서는아치의지표들이정상에비하여높을가능성이있다고생각하였으나결과는각군간에차이가없었다. 뒤꿈치통증환자에서아치가정상보다낮다는보고 9) 가있으며, 정상군과뒤꿈치바닥통증환자군에서성별을구분하여분석하면유의한차이가있다는보고 7) 가있다. 이번연구에서는방사선계측치와삼차원스캔을이용한계측치에서모두유의한차이가없다는결과를얻었다. 이번연구는삼차원스캔을한경우만을대상으로분석하였으므로대상자의숫자가적어서성별을구분하여분석하지못한것이이와같이차이가없다는결과가나온원인일가능성이있다. 각군간에통계적인유의성이없다는사실도중요하지만, 각각의계측치들이정규분포를하기때문에각각의군에서계측치가큰사람, 작은사람등이있을수있다는의미이며일정하게작거나큰경향이있는것은아니라는것도중요한의미가있다. 본연구의문제점은체중과연령에따른종아치변화의가능성을고려하지않았다는점, 성별을구분하지않았다는점, 연구대상자의수가적다는점들을들수있을것이다. 체중을고려하지는않았으나발길이와볼너비 (ball width) 가남녀모두에서키와상관관계가있다는보고 1) 가있어서신장을표준화하여신장이 170 cm로표준화한상태에서발길이를표준화하여아치높이를분석하였다. 특히성별에따라서발의여러가지측정치들이다르다는보고들 5,11) 이있으므로향후에는성별, 연령, 체중등을고려하여다수를대상으로연구하여야더욱의미있는결과를얻을수있을것이라고사료된다. 결론본연구에서는정상인과전족부통증환자군, 뒤꿈치통증환자군사이에내측종아치의높이와부피에차이가없다는결과를얻었으며, 향후에더많은대상자를성별, - 11 -
연령, 체중등에따라서세분하여연구하여야더욱의미있는결론을내릴수있을것이라고판단한다. REFERENCES 1. Baba K: Foot measurement for shoe construction with reference to the relationship between foot length, foot breadth and ball girth. J Hum Ergol (Tokyo), 3: 149-156, 1974. 2. Bergmann JN: The Bergmann foot scanner for automated orthotic fabrication. Clin Podiatr Med Surg, 10: 363-375, 1993. 3. Kim S, Yang DC, Kim MJ, et al: Three Dimensional Analysis of the Medial Longitudinal Arch of Foot. J Korean Acad Rehab Med, 28: 469-476, 2004. 4. Lee BK: Development of 3-D measurement system for shoe industry. Master Thesis, Graduate School, Seoul National University, 2003. 5. Lee WJ, Lee DK, Jang SH, Lee SG and Park SB: Gender differences in adult foot shape with 3D Foot Scanner. J Korean Acad Rehab Med, 30: 626-631, 2006. 6. Mochimaru M, Kouchi M and Dohi M: Analysis of 3-D human foot forms using the free form deformation method and its application in grading shoe lasts. Ergonomics, 43: 1301-1313, 2000. 7. Moon HT, Moon JS and Lee WC: A radiographic analysis of the feet in heel pain. J Korean Foot Ankle Soc, 9: 9-12, 2005. 8. Morag E and Cavanagh PR: Structural and functional predictors of regional peak pressures under the foot during walking. J Biomech, 32: 359-370, 1999. 9. Prichasuk S and Subhadrabandhu T: The relationship of pes planus and calcaneal spur to plantar heel pain. Clin Orthop Relat Res, 306: 192-196, 1994. 10. Smith KE, Commean PK, Robertson DD, Pilgram T and Mueller MJ: Precision and accuracy of computed tomography foot measurements. Arch Phys Med Rehabil, 82: 925-929, 2001. 11. Wunderlich RE and Cavanagh PR: Gender differences in adult foot shape: implications for shoe design. Med Sci Sports Exerc, 33: 605-611, 2001. - 12 -