Cloud-based Preoperative Planning for Total Hip Arthroplasty: A Study of Accuracy, Efficiency, and Compliance

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1 Section Editor: Bennie G.P. Lindeque, MD Cloud-bsed Preopertive Plnning for Totl Hip Arthroplsty: A Study of Accurcy, Efficiency, nd Complince Joseph D. Mrtt, MD; Rmesh C. Srinivsn, MD; Willim J. Dhl, MD; Peter L. Schilling, MD; Andrew G. Urquhrt, MD Abstrct: As digitl rdiogrphy becomes more prevlent, severl systems for digitl preopertive plnning hve become vilble. The purpose of this study ws to evlute the ccurcy nd efficiency of n inexpensive, cloud-bsed digitl templting system, which is comprble with cette templting. However, cloud-bsed templting is substntilly fster nd more convenient thn cette templting or loclly instlled softwre. Although this is prcticl solution for this prticulr medicl ppliction, regultory chnges re necessry before the tremendous dvntges of cloud-bsed storge nd computing cn be relized in medicl reserch nd clinicl prctice. Totl hip rthroplsty (THA) is relible tretment for hip rthritis. Successful THA consistently relieves pin, improves function, nd restores biomechnics of the hip. However, improper component selection or mlposition cusing excessive wer, limblength discrepncy, frcture, or disloction cn led to erly filure or ptient disstisfction. Therefore, preopertive plnning is n importnt step for chieving successful outcome fter THA. 1-4 Prior studies exmining the ccurcy of templting hve shown more thn 90% ccurcy to within 2 sizes of the Drs Mrtt, Srinivsn, Dhl, Schilling, nd Urquhrt re from the Deprtment of Orthopedic Surgery, University of Michign, Ann Arbor, Michign. Drs Mrtt, Srinivsn, Dhl, Schilling, nd Urquhrt hve no relevnt finncil reltionships to disclose. Correspondence should be ddressed to: Andrew G. Urquhrt, MD, Deprtment of Orthopedic Surgery, University of Michign, 2912 Tubmn Center, 1500 E Medicl Center Dr, Ann Arbor, MI (ndrewu@med. umich.edu). doi: / implnt. However, the exct size of the component ws predicted in only 42% to 50% of cses for the cetbulr component nd 68% for the femorl component. 4,5 As digitl rdiogrphy hs become more prevlent, tools for digitl preopertive plnning hve become vilble for use by the treting surgeon. On-screen evlution of digitl imging does not ffect the ccurcy of interprettion. 6-8 However, when printed digitl rdiogrphs re combined with cette overly templting, correct component size is predicted ccurtely only 69% of the time. 9 Studies investigting the ccurcy of digitl templting hve produced vried results. Gonzlez Dell Vlle et l 10 showed consistently better ccurcy with conventionl templting compred with digitl templting in study of 69 ptients undergoing cemented THA. In contrst, Iorio et l 11 reported tht the men errors did not differ significntly nd concluded tht both cette nd digitl templting cn ccurtely predict the size of THA implnts. For these studies, digitl templting ws performed using softwre pckges instlled on site. 10,11 In the current study, the uthors used cloud-bsed softwre for digitl templting (HipCAT; University of Michign, Ann Arbor, Michign). Cloud computing is reltively new model in informtion technology tht provides fee-for-service ccess to computing resources vi the Internet. 12 It voids the high costs ssocited with trditionl in-house computing infrstructure deployment nd expnsion. Insted, computing is provided s metered service nd resembles the service provided by public utility compny tht supplies gs or electricity Advoctes of this model highlight its low cost, ese of doption, sclbility, nd performnce. 14,15 However, the model continues to be chllenged by concerns over privcy nd security. 12,16-18 Mny of the dvntges of cloud computing re pplicble to digitl templting 682 ORTHOPEDICS Helio.com/Orthopedics

2 systems. This digitl templting system did not require the purchse of dditionl hrdwre or softwre or softwre deployment. It lso voided the expense ssocited with systems integrtion by providing utility to import imges into the cloud sved from picture rchiving nd communiction systems (PACS) viewer (McKesson Corp, Sn Frncisco, Cliforni). All functions required for templting, reviewing, nd uploding imges re ccessible through Web browser. Privcy nd security concerns were ddressed with Helth Insurnce Portbility nd Accountbility (HIPAA)-complint encryption implemented on the Web browser bsed client nd the cloud-bsed service. The purpose of this study ws to mesure the ccurcy nd efficiency of cloud-bsed digitl nd cette templting for preopertive plnning of THA. The uthors lso ddress the regultory complince issues relted to cloud computing. Mterils nd Methods A retrospective review of 20 primry uncemented THAs performed between September nd December 2010 under the direction of 1 dult reconstruction fellowship-trined surgeon (A.G.U.) ws performed. Ptients who underwent prior THA on the contrlterl hip, hd metl implnts on the opertive side, or hd nonstndrd imging were excluded from the study. Stndrdized techniques were pplied when preopertive rdiogrphy ws obtined. Anteroposterior pelvis rdiogrphs were downloded from the PACS system. The downloded imges were deidentified nd then printed on nlog film or uploded s n encrypted file into the cloud-bsed templting softwre. The imges were then clibrted in the templting system bsed on the scling overly used by the PACS system nd mgnifiction mrker when present. In seprte session, the opertive report ws reviewed to determine the ctul implnted cetbulr nd femorl components for lter sttisticl comprison. Mesurement of Templting Accurcy One ttending (A.G.U.) nd 2 senior orthopedic surgicl residents (R.C.S., W.J.D) performed preimplnt ssessments of hip implnt sizing on the 20 cses with trditionl cette templtes nd with digitl templting softwre. This ws done in 2 sessions spced 2 weeks prt. Acette templting ws performed ccording to previously described stndrdized method. 3,17 Digitl templting ws performed ccording to the digitl templting softwre protocol, llowing mrking nd mesurement similr to cette templting (Figure). The templte results for both methods were compred with the ctul cetbulr nd femorl components implnted. Mesurement of Templting Timing The preprtion of ech preopertive pln by both methods ws individully timed by n Figure: Anteroposterior view of the pelvis fter preopertive plnning with digitl templtes. observer (J.D.M.) nd recorded. The timer begn when ech film ws hung on the lightbox or the imge ws loded. The timer ws stopped when the prticipnt indicted stisfction with the templting. Sttisticl Anlysis PASW Sttistics version 19 softwre (IBM, Armonk, New York) ws used for sttisticl nlysis. Interrter relibility ws mesured with intrclss correltion coefficients. Twotiled 1-smple t tests were used to ssess the ccurcy of templting by both of these methods for ech prticipnt. The time required to templte by ech method ws lso recorded. Differences in time for ech method of templting were nlyzed using pired t tests. Results Mesurement of Templting Accurcy Digitl templting predicted correct cetbulr component size within 2 sizes in 96% of cses nd within 1 size in 73% of cses. Acette overly templting ws similrly ccurte to 2 sizes in 86% of cses nd to 1 size in 63% of cses. Digitl templting predicted correct femorl component size within 2 sizes in 93% of cses nd 1 size in 75% of cses. Acette templting ws ccurte to 2 sizes in 98% of cses nd 1 size in 93% of cses. Tble 1 shows the distribution of error by size for ech component. Moderte nd comprble interrter relibility ws found with digitl nd cette templting of the cetbulr component (Tble 2). However, slightly lower interrter relibility ws found with cette templting of the femorl component compred with the digitl method. Anlysis of pooled mesurement dt showed significnt underprediction of femorl nd cetbulr component size with digitl nd cette AUGUST 2012 Volume 35 Number 8 683

3 Tble 1 Distribution of Acetbulr nd Femorl Component Error Acetbulr Component, % Femorl Component, % Error (sizes) Digitl Acette Digitl Acette Negtive error is underprediction of size. Tble 3 Acetbulr Component Size Accurcy Tble 2 Interrter Relibility s Assessed With Intrclss Correltion Coefficients Method Acetbulr Component Femorl Component Digitl Acette P,.001. Tble 4 Femorl Component Size Accurcy Prticipnt Digitl Error P Acette Error P , , ,.05 Combined , ,.05 Negtive error is underprediction of size. Prticipnt Digitl Error P Acette Error P , , ,.05 Combined , ,.05 Negtive error is underprediction of size. overly templting (Tbles 3, 4). Digitl mesurements resulted in greter underprediction of femorl component size (negtive error vlues, P,.005). Acette mesurements resulted in greter underprediction of cetbulr Tble 5 Time Required for Completion of Templting Prticipnt Digitl Time, sec Acette Time, sec P , , ,.005 Combined ,.005 component size (negtive error vlues, P,.05). However, the stndrd devition of the estimtion error with both digitl nd cette templting is reflective of the number of cses in which the components were oversized. Mesurement of Templting Timing Anlysis of the time required to complete the tsks reveled tht cette templting on verge took 2.07 times longer thn digitl templting. Although some vrition existed in the mount of time required for completion of the tsk by ech prticipnt, cette templting ws consistently slower (1.47 to 2.53 times longer to complete the tsk depending on the prticipnt). On verge, digitl templting required 64 seconds per cse nd cette templting required 133 seconds per cse (P,.005). Results for ech prticipnt re shown in Tble 5. Discussion In the current study, digitl nd cette templting were comprbly ccurte for plnning THA. Digitl nd cette templting predicted components to within 2 sizes in the vst mjority of cses (.90% of the time). Digitl nd cette templting lso showed comprble interrter relibility for the selection of ech component. The results re comprble with prior studies of the ccurcy of digitl nd cette preopertive templting with uncemented THA. Iorio et l 11 reported tht components could be predicted within 1 size in 60% to 74% of cses with digitl templting nd in 77% to 78% of cses with cette templting. The current uthors results showed prediction of components within 1 size in 73% to 75% of cses with digitl templting nd 58% to 93% of cses with cette templting. These results re lso comprble with prior 684 ORTHOPEDICS Helio.com/Orthopedics

4 studies exmining the ccurcy of cette templting in plnning uncemented THA; these studies reported exct prediction of component size 42% to 68% of the time nd within 2 sizes greter thn 90% of the time. 4,5 In contrst, Gonzlez Dell Vlle et l 10 reported tht nlog templting ws more predictble nd precise thn digitl templting. In their study, nlog templting predicted components within 1 size in 97% to 98% of cses, wheres digitl templting from scnned nlog rdiogrphs predicted components within 1 size in 81% to 94% of cses. However, in their study, cemented technique ws used for plcement of the femorl stem. 10 Multiple investigtors hve reported tht prediction of cemented components is more relible in preopertive plnning thn prediction of uncemented components. 10,18-20 Thus, if cemented technique for the femorl stem is used, nlog templting my be more ccurte thn digitl templting. To the uthors knowledge, no other studies to dte hve exmined the efficiency of nlog nd digitl templting. This study showed tht surgeons needed pproximtely hlf the time to prepre preopertive pln with digitl templting when compred with nlog templting. With the incresing prevlence of digitl rdiogrphy nd use of PACS in the hospitl nd office setting, digitl templting my be more efficient nd cost-effective method for preopertive plnning. Potentil benefits to surgeon nd hospitl include reduced expense from film production, secure storge, improved ccess, nd incresed efficiency of templting. Another dvntge of digitl templting is the ese of error correction. As result, digitl templting is vluble tool for teching nd discussion of cses, especilly in teching hospitl setting. A cloud-bsed system confers dditionl benefits beyond trditionl on-site PACS nd digitl templting systems. Cloud-bsed systems for electronic helth records nd medicl imging softwre my lower finncil brriers nd promote cquisition. 12 However, questions remin regrding the security nd privcy of informtion stored on these systems. Use of these systems in medicl pplictions must comply with the privcy nd security rules of the HIPAA Act nd of the Helth Informtion Technology for Economic nd Clinicl Helth Act. Federl lw requires tht third prties hndling protected helth informtion enter into Business Associte Contrct with the client tht stipultes dherence to privcy guidelines. Libility now extends to the business ssocites for violtions of the security provisions. 12,21 Development of these systems with focus on enhnced security is sensible when storing sensitive medicl dt. The digitl templting system used in this study encrypts ll medicl dt on the locl computer prior to trnsmission nd storge. With this pproch, in the event of security brech of the cloud, the dt remin unintelligible without ech user s encryption key. 15,22 These pproches to security nd legisltive policy mke the use of cloud computing fesible in the medicl industry. Conclusion Preopertive plnning for THA with cloud-bsed digitl templting is comprble with cette templting in ccurcy but offers the dditionl benefits of efficiency, cost svings, nd workflow improvement. Cloud-bsed medicl softwre cn be sfely implemented in complince with federl privcy nd security regultions. However, individul physicins nd institutions should be judicious consumers of nscent technology with potentil security nd privcy pitflls. References 1. Berry DJ, Hrmsen WS, Cbnel ME, Morrey BF. Twenty-five-yer survivorship of two thousnd consecutive primry Chrnley totl hip replcements: fctors ffecting survivorship of cetbulr nd femorl components. J Bone Joint Surg Am. 2002; 84(2): Chrnley J. Totl hip replcement by low-friction rthroplsty. Clin Orthop Relt Res. 1970; 72: Dell Vlle AG, Pdgett DE, Slvti EA. Preopertive plnning for primry totl hip rthroplsty. J Am Acd Orthop Surg. 2005; 13(7): Unnnuntn A, Wgner D, Goodmn SB. The ccurcy of preopertive templting in cementless totl hip rthroplsty. J Arthroplsty. 2009; 24(2): Crter LW, Stovll DO, Young TR. Determintion of ccurcy of preopertive templting of noncemented femorl prostheses. J Arthroplsty. 1995; 10(4): Roos JE, Chill B, Znetti M, et l. MRI of meniscl lesions: soft-copy (PACS) nd hrd-copy evlution versus reviewer experience. AJR Am J Roentgenol. 2006; 186(3): Shields T. PACS: pst, present nd future. Rdiol Technol. 2010; 81(5): Eklund K, Jonsson K, Lindblom G, et l. Are digitl imges good enough? A comprtive study of conventionl filmscreen vs digitl rdiogrphs on printed imges of totl hip replcement. Eur Rdiol. 2004; 14(5): Conn KS, Clrke MT, Hllett JP. A simple guide to determine the mgnifiction of rdiogrphs nd to improve the ccurcy of preopertive templting. J Bone Joint Surg Br. 2002; 84(2): Gonzlez Dell Vlle A, Comb F, Tvers N, Slvti EA. The utility nd precision of nlogue nd digitl preopertive plnning for totl hip rthroplsty. Int Orthop. 2008; 32(3): Iorio R, Siegel J, Specht LM, Tilzey JF, Hrtmn A, Hely WL. A comprison of cette vs digitl templting for preopertive plnning of totl hip rthroplsty: is digitl templting ccurte nd sfe? J Arthroplsty. 2009; 24(2): Schweitzer EJ. Reconcilition of the cloud computing model with US federl electronic helth record regultions. J Am Med Inform Assoc. 2011; 19(2) Ktzn Jr H. On n ontologicl view of cloud computing. J Service Sci. 2010; 3(1): Ntionl Institute of Stndrds nd Technology. Cloud Computing. AUGUST 2012 Volume 35 Number 8 685

5 nist.gov/itl/cloud/index.cfm. Accessed August 11, Armbrust M, Fox A, Griffith R, et l. A view of cloud computing. Commun ACM. 2010; 53(4): Ktzn Jr H. On the privcy of cloud computing. Int J Mng Info Syst. 2010; 14(2): Cllghn JJ, Rosenberg AG, Rubsh HE. The Adult Hip. 2nd ed. Phildephi, PA: Lippincott Willims & Wilkins; Gonzlez Dell Vlle A, Slullitel G, Picclug F, Slvti EA. The precision nd usefulness of preopertive plnning for cemented nd hybrid primry totl hip rthroplsty. J Arthroplsty. 2005; 20(1): Knight JL, Atwter RD. Preopertive plnning for totl hip rthroplsty. Quntitting its utility nd precision. J Arthroplsty. 1992; 7(suppl): The B, Diercks RL, vn Ooijen PM, Vn Horn JR. Comprison of nlog nd digitl preopertive plnning in totl hip nd knee rthroplsties. A prospective study of 173 hips nd 65 totl knees. Act Orthop. 2005; 76(1): U.S. Deprtment of Helth & Humn Services. Business Assocites. gov/ocr/privcy/hip/understnding/coveredentities/businessssocites.html. Accessed August 11, Amzon Web Services. Creting HIPAA-Complint Medicl Dt Applictions With AWS. whitepper-hip/. Accessed August 11, ORTHOPEDICS Helio.com/Orthopedics