From theof Sports MeRush Univer(M.E.S.), NeCenter San DMedical Cen

The authofunding: E.Calties from SArthroscopythopaedics, Jand NephewMedical-OrthStryker, andB.Braun, thpaedic SocietArthrex, ArtCarticept, C

Quality and Variability of Online Available PhysicalTherapy Protocols From Academic Orthopaedic

Surgery Programs for Anterior Cruciate LigamentReconstruction

Eric C. Makhni, M.D., M.B.A., Erica K. Crump, M.D., Michael E. Steinhaus, M.D.,Nikhil N. Verma, M.D., Christopher S. Ahmad, M.D., Brian J. Cole, M.D., M.B.A., and

Bernard R. Bach Jr., M.D.

Purpose: To assess the quality and variability found across anterior cruciate ligament (ACL) rehabilitation protocolspublished online by academic orthopaedic programs. Methods: Web-based ACL physical therapy protocols from UnitedStates academic orthopaedic programs available online were included for review. Main exclusion criteria includedconcomitant meniscus repair, protocols aimed at pediatric patients, and failure to provide time points for thecommencement or recommended completion of any protocol components. A comprehensive, custom scoring rubric wascreated that was used to assess each protocol for the presence or absence of various rehabilitation components, as well aswhen those activities were allowed to be initiated in each protocol. Results: Forty-two protocols were included for reviewfrom 155 U.S. academic orthopaedic programs. Only 13 protocols (31%) recommended a prehabilitation program. Fiveprotocols (12%) recommended continuous passive motion postoperatively. Eleven protocols (26%) recommendedroutine partial or noneweight bearing immediately postoperatively. Ten protocols (24%) mentioned utilization of asecondary/functional brace. There was considerable variation in range of desired full-weight-bearing initiation (9 weeks),as well as in the types of strength and proprioception exercises specifically recommended. Only 8 different protocols(19%) recommended return to sport after achieving certain strength and activity criteria. Conclusions: Many ACLrehabilitation protocols recommend treatment modalities not supported by current reports. Moreover, high variability inthe composition and time ranges of rehabilitation components may lead to confusion among patients and therapists.Level of Evidence: Level II.

successful anterior cruciate ligament (ACL)

Areconstruction should enable patients to return totheir preinjury levels of activity and competition aftersurgery. This return to activity, however, is contingent

Department of Orthopaedics (E.C.M., N.N.V., B.J.C.) and Sectiondicine, Sports Medicine Fellowship Program Director (B.R.B.),sity Medical Center, Chicago, Illinois; Hospital for Special Surgeryw York, New York; Department of Orthopaedics, Naval Medicaliego (E.K.C.), San Diego, California; and Columbia University

ter (C.S.A.), New York, New York, U.S.A.rs report the following potential conflicts of interest or sources of.M. receives support from Physalife, as well as publishing roy-pringer. N.N.V. receives support from Arthrex, Arthroscopy,Association Learning Center, Arthrosurface, Cymedica, DJ Or-ournal of Knee Surgery, Minivasive, Omeros, Slack, Smith, Athletico, ConMed Linvatec, Miomed, Mitek, and Vindicoopedics Hyperguide. C.S.A. receives support from Arthrex,Major League Baseball. B.J.C. receives support from Aesculap/e American Journal of Orthopedics, the American Ortho-y for Sports Medicine, American Shoulder and Elbow Surgeons,hroscopy, Arthroscopy Association of North America, Athletico,ytori, DJ Orthopaedics, Elsevier Publishing, International

Arthroscopy: The Journal of Arthroscopic and Related

upon completion of a rigorous postoperative physicaltherapy program.1 Given the importance of post-operative physical therapy in restoring motion, strength,and conditioning, there has been substantial, high-level

Cartilage Repair Society, Journal of Bone and Joint Surgery-American,Journal of Shoulder and Elbow Surgery, Journal of the AmericanAcademy of Orthopaedic Surgeons, Medipost, National Institutes ofHealth (National Institute of Arthritis and Musculoskeletal and Skin Diseasesand Eunice Kennedy Shriver National Institute of Child Health and HumanDevelopment), Ossur, Regentis, Saunders/Mosby-Elsevier, Slack, Smith &Nephew, Tornier, and Zimmer. B.R.B. receives support from Arthrex, Smith& Nephew, Conmed Linvatec, Tornier, Ossur, Mitek, Athletico, the AmericanOrthopaedic Society for Sports Medicine Medical Publishing Group Board ofDirectors, and Slack.Received August 5, 2015; accepted January 14, 2016.Address correspondence to Eric C. Makhni, M.D., M.B.A., Department of

Orthopaedics, Rush University Medical Center, 1611 West Harrison, Suite300, Chicago, IL 60612, U.S.A. E-mail: ericmakhnimd@gmail.com� 2016 by the Arthroscopy Association of North America0749-8063/15738/$36.00http://dx.doi.org/10.1016/j.arthro.2016.01.033

Surgery, Vol -, No - (Month), 2016: pp 1-10 1

Table 1. Rehabilitation Protocol Components

Prehabilitation Range of motion, quadriceps strengtheningPostoperativeadjunct therapy

Continuous passive motion, brace use,neuromuscular electric stimulation

Early motion andweight bearing

Flexion/extension goals, weight-bearingparameters

Strengthening Straight-leg raise, resisted straight-leg raise,quadriceps sets/isometrics, ankle pumps,minisquats, squats, hamstring curls, resistedhamstring curls, leg press, step-up/down,wall sits, single-leg squats, resisted kneeextension, lunges

Proprioception Weight shifting, 1-leg balance, balance board,ball toss, perturbation, balance beam,Theraband control, mini-trampolinebalance

Functional testing Single-hop test, 3-hop test, isokineticquadriceps strength, isokinetic hamstringstrength, quadriceps/hamstring strengthratio, or nonspecific functional test

Activity/sport Stationary bike, backwards walking, normalgait, elliptical, stair climber, aqua jogging,underwater treadmill, swimming,backwards running, straight-line running/jogging, jumping/plyometrics, cutting/pivoting, agility (carioca, side shuffle),sport-specific drills, return to practice/sport

2 E. C. MAKHNI ET AL.

research effort in determining the clinical benefit ofvarious components of ACL rehabilitation.2-10 Measuresthat appear to be of clinical benefit include early weightbearing and motion, while those with evidence indi-cating no benefit include continuous passive motion(CPM), secondary (functional) postoperative bracing,and decreasing the time to return to sport (“acceleratedphysical therapy”).11,12

In the United States, there is a movement to transitionto a value-driven health care system in which economicresources are invested in health care measures thatproduce clear clinical benefit.13-18 In ACL reconstruc-tion, a large proportion of postoperative resource utili-zation arises from physical therapist-supervisedrehabilitation. Consequently, several studies haveattempted to determine the impact of such clinical su-pervision on functional outcomes. These studies reportno clear clinical benefit in patients undergoing pre-dominately supervised physical therapy compared withthose undergoing home-based programs.8,12,19-21 Giventhe rising importance of home-based physical ther-apy,20 it is imperative to determine whether theseprotocols employ current published principles in ACLrehabilitation. Moreover, significant variability betweenprotocols may lead to patient and clinician confusionregarding which protocol to follow. As multiple studies,including those of postoperative orthopaedic rehabili-tation, have suggested a correlation between improvedclinical benefits and standardization of clinical carepathways,14,15,17,18,22-24 a baseline assessment of thevariability within these protocols is also warranted.To minimize variability due to individual provider

preference, protocols from academic orthopaedic pro-grams were the focus of this study. The purpose of thisstudy was to assess the quality and variability foundacross ACL rehabilitation protocols published online byacademic orthopaedic programs. We hypothesize thatonly a minority of physical therapy protocols willdemonstrate adherence to published best practices inACL rehabilitation and that there will be substantialvariability in the composition and timing of rehabilita-tion components across different protocols.

MethodsThis investigation reviewed publicly available physical

therapy protocols from U.S. academic orthopaedicsurgery programs. Academic programs were selectedfor initial screening to avoid selection bias of incorpo-rating protocols obtained from search engines online. Alist of academic orthopaedic surgery programs in theUnited States was obtained from the Electronic Resi-dency Application Service. Websites from these pro-grams, along with a general web-based search (www.Google.com), were then used to identify any officialACL reconstruction rehabilitation protocols affiliatedwith the program using the search term “[Program/

affiliate hospital/affiliate medical school name] ACLreconstruction rehabilitation protocol” during searchesundertaken in December 2014. Protocols wereexcluded from review if they were designed for pedi-atric patients, involved combined meniscus repair, ordid not provide any time points for the commencementor recommended completion of any protocolcomponents.For each program, all official ACL rehabilitation pro-

tocols were reviewed and assessed by the study teamaccording to a custom rubric created for this study afterfull review of all available rehabilitation protocols. Thisrubric included scoring sections for relevant metrics andwas created according to a comprehensive literaturereview of available studies and protocols regardingcomponents of ACL rehabilitation. The assessment ofquality of the protocol focuses on adherence to pub-lished guidelines regarding ACL rehabilitation, whilethe assessment of variability among protocols focuseson the different rehabilitation components found in theindividual protocols as well as on the suggested pointsin the recovery process at which these components arerecommended. The following broad categories withineach protocol were defined: prehabilitation, post-operative adjunct therapy, range of motion and weightbearing, strengthening exercises, proprioception exer-cises, return to activity/sport, and functional testing.The complete listing of reviewable metrics is listed inTable 1. The primary outcome of this study was inclu-sion, or exclusion, of these metrics in each identifiedrehabilitation protocol. The secondary outcome was the

Fig 1. Flow diagram for thestudy. (ACL, anterior cruciateligament; BTB, bone-tendon-bone; ERAS, electronic resi-dency application service; HS,hamstring.)

VARIABILITY IN ACL PHYSICAL THERAPY PROTOCOLS 3

appropriate timetable for commencement of these in-dividual components. For example, with regards tosingle-leg squats, inclusion or exclusion of this activitywas noted for each protocol, as well as when (in therecovery period) this activity was allowed to beattempted.

ResultsIn total, 155 programs were included for review.

Thirty-three of these 155 academic orthopaedic pro-grams (21%) provided publicly available (online)rehabilitation programs that met the eligibility criteria,with a total of 42 protocols that were included in thisstudy (Fig 1).

PrehabilitationOf the 42 included protocols, 13 (31%) explicitly

recommended a preoperative rehabilitation activity set(Fig 2A). Six protocols (14%) specifically delineatedtypes of range-of-motion activities to complete, and 8protocols (19%) explicitly recommended quadricepsstrengthening exercises.

Postoperative Adjunct TherapyThree types of postoperative adjunct therapies were

assessed (Fig 2B): bracing (both immediate post-operative as well as functional/secondary), CPM, andneuromuscular electric stimulation (NMES; as anassist to quad strengthening). An overwhelmingmajorityd40 of 42 protocols (95%)drecommendedimmediate postoperative bracing. In the 2 protocols

Fig 2. (A) Preoperative and (B)earlypostoperativevariability inphysical therapy protocols. (A)Prehabilitation was mentionedin approximately 30% ofprotocols. (B) Ten percent ofprotocols continued to advocatefor routine CPM use post-operatively, and approximately20% of protocols recom-mended routing postoperativefunctional bracing followingrecovery. (CPM, continuouspassive motion; NMES, neuro-muscular electric stimulation;quad, quadriceps; ROM, rangeof motion.)

4 E. C. MAKHNI ET AL.

that did not recommend this type of bracing, therewas no written recommendation (either for or against)regarding immediate postoperative bracing. Tendifferent protocols (24%) reported guidelines for

Fig 3. Time-based goals forachieving range-of-motion mile-stones. The target time point forachieving full flexion ranged from0 weeks postoperatively to 12weeks postoperatively. Thenumbered line within each rangeindicates median of data set. (Deg,degrees.)

transitioning to a “secondary” or postrecovery func-tional brace. These guidelines included either recom-mendations for transitioning to a secondary brace orinstructions to consult with a clinician prior to

Fig 4. (A) Strengtheningand (B) proprioceptionexercises. A significantvariation was found withregards to composition ofboth types of exercises inrehabilitation protocols.(HS, hamstring; quad,quadriceps; SLR, straight-leg raise.)

VARIABILITY IN ACL PHYSICAL THERAPY PROTOCOLS 5

transitioning to a secondary functional brace. Fiveprotocols (12%) recommended CPM use. Approxi-mately half of all protocols (22 of 42; 52%) recom-mended NMES as a useful adjunct to quadricepsstrengthening efforts. Most of these protocols (20 of22) recommended commencement of NMES in thefirst postoperative week, while the remaining 2 pro-tocols recommended initiation starting 1 weekpostoperatively.

Early Motion and Weight BearingAll protocols (42 of 42) recommended immediate

motion postoperatively. Every protocol similarly gavecompletion goals dates by which to achieve fullextension (Fig 3). For range-of-motion milestoneswith regards to flexion, 26 protocols (62%) set goalsfor 90� of flexion, compared with 31 and 37 protocols(74% and 88%, respectively) that set goals for 110�

or 120� of flexion and full flexion (>135�),respectively.

Regarding postoperative weight bearing, there were11 protocols (26%) that recommended either routinepartial weight bearing or routine noneweight bearingfor at least the first week after surgery. There was a9-week range in the stated goal for achieving fullweight bearing (1 to 10 weeks postoperatively, with amedian of 3 weeks).

StrengtheningFourteen different basic strengthening exercises were

included in the rubric for assessing ACL physical ther-apy protocols (Table 1). On average, each protocolpresented an average of 7.2 different strengtheningexercises (Fig 4A). Only 4 protocols (9.5%) providedclear instruction on the proper mechanics in perform-ing these exercises. Seven of 14 exercises appeared ingreater than 50% of protocols. Wide variation wasidentified with regards to earliest commencement datesof the most common strengthening exercises (thoseappearing in >50% of protocols; Fig 5A). Among the

Fig 5. (A) Strengtheningand (B) proprioception ex-ercises. Significant variationwas found with regards toallowable start times forexercises. Numbered linewithin each range indicatesmedian of data set. (HS,hamstring; quad, quadri-ceps; SLR, straight-legraise.)

6 E. C. MAKHNI ET AL.

strengthening exercises with highest variability werestep-up/step-down exercises (16 weeks range forearliest start date), as well as hamstring curls and legpress (each with an earliest allowable start date ofaround 12 weeks).

ProprioceptionEight different proprioceptive exercises were included

in the rubric for assessing ACL physical therapy pro-tocols (Table 1). On average, each protocol presentedan average of 2.4 different proprioceptive exercises (Fig4B). Two of 8 proprioceptive exercises appeared ingreater than 50% of protocols. As with the strength-ening exercises, wide variation was identified withregards to earliest commencement dates of the mostcommon strengthening exercises (those appearing in>50% of protocols; Fig 5).

Return to Activity/SportWith respect to return to sport guidelines and pre-

requisites, 5 protocols (12%) failed to mention returnto sport as a goal of ACL rehabilitation. Only 8 differentprotocols (19%) recommended return to sport afterachieving certain strength and activity criteria.Each protocol was additionally assessed for inclusion

of a variety (n ¼ 15) of different rehabilitation activities(Fig 6A). Of these 15 activities, 11 activities (73%)appeared in greater than 50% of protocols. Again,considerable variability with respect to earliest startdates was noted across these rehabilitation activities(Fig 6B).

Functional TestingSix different functional activity components were

included in the study’s rehabilitation rubric (Fig 7A).

Fig 6. (A) Return to activity/sports and (B) start dates.Numbered line within eachrange indicates median of dataset.

VARIABILITY IN ACL PHYSICAL THERAPY PROTOCOLS 7

None of these functional tests appeared in greaterthan 50% of physical therapy protocols. As with othervariables, substantial variation existed in allowablestart times for these functional activity components(Fig 7B).

DiscussionThe results of this study indicate that only a minority

of academic programs publish ACL physical therapyprotocols online and that within these protocols, thereis a significant amount of variation with regards toexercises incorporated and timing of rehabilitationmilestones. Several of these protocols were found toprovide guidelines for rehabilitation practices that havebeen shown to provide no meaningful clinical benefit(such as secondary bracing and CPM), and most pro-tocols lacked clear instruction in performing variousfunctional and athletic activities. Moreover, substantialvariation existed with regards to both the type ofrehabilitation components included in the study pro-tocols as well as to the earliest start dates of these

protocols. This variation of included components isindicative of the general lack of consensus regardingbest-practice components of ACL rehabilitation andrepresents a possible area for increased processstandardization.The study authors were surprised to find that such a

low proportion of academic orthopaedic programsmade their ACL physical therapy protocols availableonline. Moreover, these protocols were typically notdirected toward a patient readership. It is likely thatmany orthopaedic surgeons provided individualizedprotocols to patients either directly or through affiliatedphysical therapists. However, there has been a trendtoward increased emphasis on home-based physicaltherapy, given the numerous clinical studies that haveconsistently reported no difference in clinical outcomebetween patients undergoing supervised versus home-based ACL rehabilitation.8,12,19-21 Moreover, becauseof the current economic pressures on the United Stateshealth care system, this dependence on home-basedcare is expected to grow. Patients are expected to be

Fig 7. (A) Functional activitycomponents and (B) start dates ofanterior cruciate ligament reha-bilitation protocols. Numberedline within each range indicatesmedian of data set. (HS, ham-strings; quad, quadriceps.)

8 E. C. MAKHNI ET AL.

increasingly proactive in matters regarding their healthcare, including education about disease conditions andtreatment.17 Therefore, patients are still likely to con-sult these online protocols for reference when navi-gating their own rehabilitation processes.Interestingly, 1 protocol was identified that specif-

ically referenced this trend in health care resourceallocation. This protocol emphasized minimal physicaltherapy sessions with an emphasis on patient educationand self-directed rehabilitation. This protocol allocatedonly 8 clinician-supervised visits over the first post-operative year. However, this protocol was the excep-tion, and similar emphasis was excluded from all otherprotocols. Because the rehabilitation process is socrucial to facilitating successful outcomes after ACLreconstruction,1,20 patients must be able to readily ac-cess their physical therapy protocols throughout therecovery period. Considering the results from thisstudy, improved online access to protocols should beconsidered.Along with adherence to published guidelines for

medicine, quality can be improved through standardi-zation of clinical care pathways. This has beendemonstrated in studies involving inpatient procedures,particularly total joint replacement.17,18,22,25 The results

from our study indicate that there is considerablevariation in both the types of components that reha-bilitation protocols recommend and in the timing atwhich that these activities may be initiated. It isreasonable to expect that individual patients may differin how quickly or aggressively they progress throughthe recovery period after ACL reconstruction. In fact,many experts have advocated for aggressive protocols1

for patients with high activity levels at baseline whomay benefit from an earlier return to sport or activity(e.g., elite athletes). However, our analysis concludedthat not only were large time ranges suggested for eachrehabilitation activity but also that there were noexplicit guidelines in these protocols that guided thepatient as to when progression to these activities wasconsidered reasonable. Before patients were expectedto manage their own rehabilitation, this omission andlack of clarity may have been acceptable as long as thepatient’s therapist was able to guide the patient throughthe recovery process. However, with patients expectedto manage their own rehabilitation, this variability andlack of clarity may create confusion and overexertion aspatients attempt to progress through the recovery pro-cess without clear guidelines. Therefore, a decrease inthe variability across these protocols may help patients

VARIABILITY IN ACL PHYSICAL THERAPY PROTOCOLS 9

navigate the recovery process more safely and with aconcomitant higher chance of successful return toactivity.While most of the evidence regarding improvement

in clinical outcomes from care standardization hasfocused on inpatient procedures, there is recent evi-dence that supports standardization in outpatientphysical therapy as well. Hando and colleagues23 fol-lowed a series of patients with hip osteoarthritis whounderwent a standardized physical therapy regimenthat consisted of interventions proven to be clinicallyeffective. The authors noted significant improvementsacross a number of functional metrics and scores. Un-fortunately, this study did not compare their evidence-driven protocol with that of a traditional protocol, butthe authors were able to provide evidence that stan-dardization of physical therapy is nonetheless highlyeffective in the outpatient setting.

LimitationsIt is important to note that this study does have

several limitations. Even though over 150 programswere considered for inclusion, only 42 protocols met allinclusion and exclusion criteria. This number representsa minority of the available ACL rehabilitation protocolsaccessible online. Moreover, combined meniscus repairprotocols were excluded. It is also likely that individualpractitioners from these academic programs may havepersonal websites that independently publish theirpreferred physical therapy protocols. However, ourmethodology was chosen to select a series of protocolswhile minimizing selection bias. A second limitation isthe incorporation of protocols designed for differentpatients (depending on graft type) into a single studycohort. In our study, there were protocols designedspecifically for bone-tendon-bone autograft that wereassessed alongside protocols designed for soft tissueautograft patients. However, in our attempt to classifythese protocols according to target patient (by graft typereceived), we found that many protocols failed toidentify a target patient population. While some exer-cises (such as resisted leg extension) may be particularlysensitive to graft type, a majority of rehabilitationcomponents are likely insensitive to this variable.Moreover, as the goal of this study was to document thevariability across different protocols, the impact ofprotocol segregation according to graft type is likely lesscontributory.

ConclusionsMany ACL rehabilitation protocols recommend

treatment modalities not supported by current reports.Moreover, high variability in the composition and timeranges of rehabilitation components may lead toconfusion among patients and therapists.

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