Does shortened length of hospital stay affect total knee arthroplasty rehabilitation outcomes
The Journal of Arthroplasty Vol. 20 No. 7 Suppl. 3 2005Does Shortened Length of Hospital Stay Affect Total Knee Arthroplasty Rehabilitation Outcomes? Steven M. Teeny, MD,* Sally C. York, MN, RNC,* Cindy Benson, MPT, OCS,y and Sondra T. Perdue, DrPH* Abstract: Rehabilitation outcomes were compared after primary total knee arthroplasty between patients who participated in a hospital joint arthroplasty program implemented to decrease length of stay and patients who did not. Once inclusion criteria were met, purposive sampling was used to select subjects for retrospective medical records review. Range of motion and Knee Society scores at preoperative and 3-, 6-, and 12-month postoperative intervals were then compared. Preoperatively, there were no significant differences between groups. Program implementation reduced length of hospital stay by a mean of 1.3 days, which resulted in a decreased range of motion at discharge. No significant differences were found between groups postoperatively at all intervals. Primary total knee arthroplasty rehabilitation outcomes were not compromised by reduced length of hospital stay. n 2005 Published by Elsevier Inc.Approximately 300 000 total knee arthroplasties However, the relationship between length of(TKAs) were performed in the United States in TKA hospital stay and clinical outcomes, as defined2003 . The American Association of Orthopedic by measures such as the Knee Society score  andSurgeons projects that, by the year 2030, this knee range of motion, has not been fully studied.number will increase to 474,319 . Because of Research in this area is important to ensure thatthe large number of patients undergoing this patient outcomes are not compromised by theprocedure each year, even a small effect on average increasing economic pressures in health care,length of stay or complication rates can have a large which may contribute to shorter length of hospitaleffect on our nation’s use of medical resources. In stays [4,6].an effort to reduce hospitalization costs, decrease The purpose of our study was to compare thepatient complications, improve quality of care, and short-term rehabilitation outcomes (up to 12increase patient satisfaction, many hospitals are months postoperatively) of a single surgeon’s pri-implementing comprehensive total joint arthro- mary unilateral TKA between patients who partic-plasty programs [3,4]. ipated in a comprehensive hospital joint arthroplasty program implemented to decrease length of stay with TKA patients before program implementation. From the *NorthWest Orthopaedic Institute, Tacoma, Washington; The hospital system involved in this studyand yPhysical Therapy Department, University of Puget Sound, selected and implemented the JointVentures JointTacoma, Washington. Camp Program designed by TeleVisual Communi- Submitted January 15, 2005; accepted April 29, 2005. No benefits or funds were received in support of this study. cations of Clearwater, Fla. This program is a Reprint requests: Steven M. Teeny, MD, NorthWest comprehensive approach to total joint rehabilita-Orthopaedic Institute, P.O. Box 1878, Tacoma, WA 98401. tion that has been implemented in more than n 2005 Published by Elsevier Inc. 0883-5403/05/1906-0004$30.00/0 250 hospitals in the United States and abroad . doi:10.1016/j.arth.2005.04.025 Program emphasis is on expectation setting by the 39
40 The Journal of Arthroplasty Vol. 20 No. 7 Suppl. 3 October 2005patient, group orientation, a wellness focus, and quadricep sets, and short-arc quadricep exercises.standardization of presurgical and postsurgical The remainder of group PT includes sit to standprotocols among the medical team and participat- transfers, turning with a walker, gait training, anding facilities . The inpatient phase is known as stair climbing. The final group PT session includesJoint Camp. As the name implies, Joint Camp is gait training with a walker, stair climbing, andintended to promote a sense of teamwork and miniature golf putting. Individual PT focuses oncamaraderie. Before surgery, patients receive stan- bed mobility, transfers, gait training, and a homedardized outpatient briefings and an orientation to exercise program consisting of ankle pumps, glutealthe Joint Camp philosophy and program. Patients sets, quadricep sets, heel slides, hamstring sets,scheduled to undergo primary total hip or knee short-arc and long-arc quadricep exercises, and hiparthroplasty are given the option of voluntarily abduction and adduction exercises.participating in this program, which features dailyindividual and group physical therapy (PT), andother group activities. Methods On the day of surgery, bcampersQ are admitted aspart of a small group. A key component of the A retrospective medical records review wasprogram is standardization of surgery schedules conducted of 110 patients after institutional reviewand procedures to accommodate more consecutive board approval was obtained from the Franciscantotal joint cases by surgeons on regular days, Health System in Pierce County, Washington.facilitating consistent use of operating rooms, Inclusion criteria consisted of patients who had aanesthesiologists, assists, and surgical teams. This primary unilateral TKA by a single surgeon (theaids the bgroupQ aspect of patient experiences senior author) at St Clare Hospital, Lakewood,preoperatively and postoperatively while improv- Wash, and patients who had Knee Society scoresing surgeon and hospital efficiency, and hospital  preoperatively and for at least 2 of thecost containment. 3 postoperative intervals of 3, 6, and 12 months. Joint Camp protocols focus on eliminating aspects Subjects were excluded from the study if they hadof postoperative care that often limit early postop- concurrent bilateral TKAs, contralateral TKA with-erative ambulation and that also increase hospital in 6 months, total hip arthroplasty within 6 months,costs. Whenever possible, Joint Camp patients’ total knee revisions, or if they had significantintravenous fluids are discontinued on postopera- comorbidities unrelated to their rehabilitation thattive day 1, instead of more commonly on postop- would make functional comparisons betweenerative day 2. Indwelling urinary catheters inserted groups inappropriate (eg, prior cerebrovascularduring surgery are discontinued in Joint Camp accident with hemiparesis).participants after a maximum of 24 hours, which The groups were selected using the method ofpromotes ambulation the first postoperative day. purposive sampling, which involved selecting par-Before Joint Camp, indwelling urinary catheters ticipants based on these specific inclusion criteria aswere usually left in up to 48 hours postoperatively. follows. Joint Camp was implemented at St Clare Before and after Joint Camp implementation, PT Hospital on November 26, 2001. All patients in thewas started twice daily starting postoperative day 1. sample who underwent TKA between NovemberContinuous passive motion machine (CPM) is not 26, 2001, and March 3, 2003, participated in Jointused in Joint Camp, which also reduces rehabilita- Camp. The first 55 of these patients to meet ourtion costs. bCoachingQ by family members or friends inclusion criteria comprised the Joint Camp group.is encouraged [8,9] in Joint Camp, and patients For the non–Joint Camp group, the first patientwear their own casual clothes during the day and included was the last to undergo surgery beforeparticipate in recreational activities and meals as a November 26, 2001. We then counted back togroup. In Joint Camp, on the first day postopera- include a total of 55 consecutive TKA patientstive, patients are assisted in dressing into their own before Joint Camp who met inclusion criteria;clothes early in the morning and then evaluated by surgery dates for this group were between Februarya physical therapist after breakfast. In the afternoon 10, 2000, and November 8, 2001. A study of thisof postoperative day 1, the patient participates in size has power of 0.74 to detect differences betweengroup PT if he or she is able and willing to do so. On 2 groups of 0.5 SDs when using t tests. Forthe second and third postoperative day, the patient example, a difference of about 58 in knee passivereceives individual PT in the morning and group PT flexion would be significantly different.in the afternoon. Group PT begins with warm-up Outpatient data were routinely obtained on allactivities consisting of ankle pumps, gluteal sets, joint arthroplasty patients by means of office
TKA Rehabilitation Outcomes ! Teeny et al 41preoperative intake forms documenting age, sex, fixed, cruciate-substituting rotating platform, orgeneral medical and surgical history, primary and TC3 cruciate-substituting knee implants. Criteriasecondary knee diagnoses, previous nonimplant for implant selection was based on age, weight,surgery on the affected knee, joint arthroplasty activity level, and preoperative knee alignment.history, and previous nonoperative treatment. All pre–Joint Camp and post–Joint CampKnee Society score  evaluations were completed patients received the same deep vein thrombosispreoperatively and postoperatively at 3, 6, and prophylaxis (dalteparin sodium, 5000 U subcuta-12 months. Passive range of motion measurements neously daily, started at 12-24 hours, for 10 dayswere included that were made at the 6-week postoperatively) in accordance with currentpostoperative outpatient follow-up visit. In addi- American College of Chest Physician guidelinestion, we documented the outpatient complications . All patients in the study received individualand interventions, and outpatient PT received in in-office preoperative education as well as hospitaltype, number of visits, and range of motion preoperative group education classes; patients inmeasurements at the initial and final visits. Joint Camp received an additional preoperative Inpatient data collection from the inpatient hospital education manual containing detailedmedical records included the operative report with hospital care and home exercise program informa-date of surgery, type of anesthesia, length of tion. Joint Camp patients and their families weresurgery, implant type; length of hospital stay, also preoperatively instructed to prepare for dis-assistive device at discharge, discharge destination, charge, specifically on the third or fourth post-inpatient complications and interventions, and use operative day.of mechanical antithrombotic devices. InpatientPT data collected included total number of PTsessions, CPM use, and range of motion measure- Resultsments at discharge. Data analysis was performed using Statistical The sample size was 110 patients; 55 patientsPackage for the Social Sciences (SPSS). An inde- were in each group. The mean age for the non–pendent t test was used to analyze demographic Joint Camp group was 69 years (range, 41-84 years);data, confounding variables at baseline, and out- the Joint Camp group had a mean age of 69.8 yearscome measurements between groups. Scores for (range, 42-86 years). The non–Joint Camp groupboth the functional and the knee rating portions of was composed of 39 women and 16 men; the Jointthe Knee Society evaluation  were calculated for Camp group was composed of 38 women andeach time interval. Range of motion and Knee 17 men. Two situations arose that caused us toSociety scores  at preoperative and 3, 6, and exclude patients who met the inclusion and exclu-12 months postoperatively were compared, along sion criteria. First, 6 patients had 2 consecutivewith demographic and clinical data. bilateral TKAs that were performed more than Before the implementation of Joint Camp on 6 months apart. We included each of these patientsNovember 26, 2001, all of the senior author’s TKA only once to eliminate bias. Secondly, 1 patient frompatients received routine inpatient postoperative PT the Joint Camp group was excluded as an outlier.in a one-on-one format. Included were knee range This patient had a complex primary TKA due to aof motion and strengthening exercises, and gait preoperative diagnosis of severe postseptic arthritistraining. Patients also received an inpatient occu- with a 208 varus deformity and 108 of medial laxity,pational therapy consultation. After November 26, and a preexisting contralateral Charcot foot with an2001, all of the senior author’s primary TKA established ankle fusion-nonunion.patients participated in Joint Camp in lieu of the Medical history of the 2 groups was notformer treatments. All patients in the non–Joint statistically different ( P N .05) in weight, tobaccoCamp group used CPM for the duration of the use, respiratory disease, renal disease, hepaticlength of hospital stay, as well as during any skilled disease, diabetes, endocrine disease, neurologicnursing facility or short-term acute rehabilitation conditions, history of thromboembolism, hyperten-length of stay. None of the Joint Camp group used sion and other cardiovascular problems, gastroin-CPM in any setting postoperatively. Before initia- testinal disease, peripheral vascular disease, cancer,tion of Joint Camp, patients were usually operated gout, phlebitis, depression, anxiety, and spinalon Thursdays; after initiation of Joint Camp, all stenosis. Preoperative diagnoses were also similarpatients were operated on Mondays. for the side of involvement, primary arthritis All patients in the study received DePuy PFC diagnoses of osteoarthritis, rheumatoid, post-Sigma cruciate-substituting or cruciate-retaining traumatic or inflammatory arthritis, previous non-
42 The Journal of Arthroplasty Vol. 20 No. 7 Suppl. 3 October 2005 Table 1. Knee Society Evaluation Scores Table 3. Primary TKA Implant TypeKnee Society Non–Joint Joint Non–Joint Camp* Joint Camp*score components Camp*O CampyO Implant type n n DePuy PFC Sigma 46 42Mean knee range of motion PCL-substituting Preoperative (8) 6-110 7-108 DePuy PFC Sigma 6 8 3 mo postoperative (8) 4-112 3-115 PCL-substituting 6 mo postoperative (8) 3-116 2-115 rotating platform 12 mo postoperative (8) 1-119 4-117 DePuy PFC Sigma 2 4Mean knee scorez (SD) PCL-sparing Preoperative 40.2 (15.4) 37.5 (14.9) DePuy PFC Sigma 1 1 3 mo postoperative 83.7 (12.8) 80.8 (12.7) PCL-substituting TC3 6 mo postoperative 87.6 (13.2) 83.8 (13.8) Total 55 55 12 mo postoperative 90.4 (12.5) 86.7 (15.18)Mean functional scorez (SD) Preoperative 47.5 (15.5) 45.6 (15.5) PCL indicates posterior cruciate ligament. 3 mo postoperative 66.2 (20.6) 61.3 (12.7) *There were no significant differences between groups for 6 mo postoperative 69.2 (22.9) 68.0 (23.7) implant type (v 2 = 1.4, df = 3, P = .70). 12 mo postoperative 72.9 (24.6) 70.0 (20.9)Mean total Knee Society score§ Preoperative 87.7 83.1 scores , and range of motion (Table 1). Among 3 mo postoperative 149.9 142.1 all of the subscores, the only significant differences 6 mo postoperative 156.8 151.8 12 mo postoperative 163.3 156.7 preoperatively found were in pain; the Joint Camp participants had more pain in the affected knee *Number of non–Joint Camp patients included are preoper- with walking (Joint Camp mean pain score, 3.45/4;ative, n = 55; 3 months postoperative, n = 47; 6 monthspostoperative, n = 42; and 12 months postoperative, n = 46. non–Joint Camp mean pain score, 3.15/4; P = .004) yNumber of Joint Camp patients included are preoperative, and more pain with stairs (Joint Camp mean painn = 55; 3 months postoperative, n = 49; 6 months postoperative, score, 3.44/4; non –Joint Camp mean pain score,n = 45; and 12 months postoperative, n = 38. zMaximum score, 100. 3.18/4; P = .047). §Maximum score, 200. The operating room time, number of PT sessions, ONo significant differences were found between the non–Joint knee passive range of motion at discharge, painCamp group and the Joint Camp group at the .05 level ofsignificance. score at discharge, and length of stay are presented in Table 2. Seventy-eight percent of the non–Joint Camp group compared with 54% of the Joint Camp group received spinal anesthesia or a combinationimplant surgery on the ipsilateral knee, previous of spinal and general, whereas 22% of the non–hip involvement, prior contralateral knee arthro- Joint Camp group and 46% of the Joint Camp groupplasty, contralateral knee problems without arthro- received general anesthesia alone. Implant distri-plasty, multiple joint arthritis, or medical infirmity. bution between the 2 groups is presented in Table 3.Five patients in the Joint Camp group reported Although the Joint Camp group was dischargedosteoporosis as opposed to none in the other group. from the hospital 1.3 days sooner than the non– There were no significant differences between Joint Camp group, without the use of CPM, thethe overall preoperative Knee Society scores  discharge destination profile was similar. Uponbetween the non–Joint Camp group and the Joint discharge, 38 patients in the non–Joint Camp groupCamp group, the Knee Society knee and functional and 32 in the Joint Camp group went home, Table 2. Inpatient Outcomes Non–Joint Camp Joint CampOutcome n Mean n Mean P*Operative time 46 85 min 39 73 min .003PT sessions 54 7.7 sessions 50 5.7 sessions .001Knee passive extension at discharge (SD) 44 1.98 (3.48) 39 8.68 (3.88) .001Knee passive flexion at discharge (SD) 44 70.68 (11.08) 39 74.08 (10.88) .165Pain scorey at discharge 40 2.85 50 2.62 .669Length of stay 54 5.7 d 50 4.4 d .022 *P value is based on independent t test for the differences between groups. yScale of 0 to 10; 0 indicates no pain, 10, extreme pain.
TKA Rehabilitation Outcomes ! Teeny et al 43 Table 4. Postoperative Complications Inpatient Posthospital discharge Non–Joint Camp Joint Camp Non–Joint Camp Joint CampComplication n n n nDeep vein thrombosis 1 0 6 3Deep vein thrombosis with pulmonary embolus 1 1 0 1Respiratory 1 2 0 0Cardiac 1 0 0 0Arthrofibrosis requiring manipulation 0 0 3 1Delayed wound healing requiring secondary closure 0 0 2 1Heel decubitus 0 0 0 1Total complications 4 3 11 7 Counts are provided as description only. Numbers are too small for statistical comparisons.whereas 4 in the non–Joint Camp group and 5 in addition, Steele et al  presented some Jointthe Joint Camp group went to an inpatient Camp outcomes at Anne Arundel Medical Center.rehabilitation facility, and 12 of the non –Joint Patient satisfaction was measured by questionnaireCamp group and 14 of the Joint Camp group went in 1999 with a range of 4.28 to 4.74 on a 5-pointto a skilled nursing facility. The incidences of scale, Joint Camp. Mahomed et al  evaluatedinpatient and outpatient complications are pre- the relationship between patient expectations ofsented in Table 4. total joint arthroplasty and health-related quality of By the 6-week follow-up visit, no significant life plus satisfaction at 6 months after surgery.range of motion differences remained between Before surgery and 6 months postsurgery, self-groups as shown in Table 5. Outpatient PT was report questionnaires were used. The Short Formsimilar in type of treatment and treatment setting, 36, WOMAC, and a satisfaction scale were theand the mean number of outpatient PT visits for the measures of outcome . The researchers foundnon –Joint Camp group was 11.7 as compared with that patient expectations, particularly expectationthe Joint Camp group mean of 11.4. of complete pain relief after surgery and expecta- No significant differences were found between tion of low risk for complications, were importantthe postoperative Knee Society functional or rating independent predictors of functional outcome andscores at 3, 6, and 12 months (Table 1). Both satisfaction after total joint arthroplasty. Expect-groups had significant improvements between all ations were not found to correlate to preoperativeKnee Society scores preoperatively and at all functional status . The average length ofintervals measured postoperatively. stay decreased from 5.2 to 3.7 days between 1994 Radiographic analysis of the 2 groups was not and 1998 . This study would support theperformed for purposes of this study. Although notion that setting expectations for patients withradiographic misalignment is known to be a factor regard to rehabilitation goals can assist in reachingin the long-term durability of total knee compo- these goals.nents; durability of components was not a focus of Standardizing surgery scheduling of total jointthis study and not expected to have much impact cases to regular specific days of the week to allowon the short-term rehabilitation outcomes. for maximizing the number of consecutive cases done in 1 day contributed to improved consistency Discussion and efficiency of the surgical team. This may have been a factor in the decreased operative time for A review of the literature on Joint Camp each case of 12 minutes in the Joint Camp patients,produced 2 journal articles that were descriptive along with the surgeon’s increased experiencein nature of the program concepts [11,12]. In over time. Table 5. Six-Week Postoperative Passive Knee Range of Motion Non–Joint Camp Joint CampKnee range of motion n Mean (SD) (8) n Mean (SD) (8) P*Knee passive extension 54 5.0 (5.1) 48 3.5 (4.2) .112Knee passive flexion 54 107.7 (13.5) 47 105.5 (12.2) .395 *P value is based on independent t test for the differences between groups.
44 The Journal of Arthroplasty Vol. 20 No. 7 Suppl. 3 October 2005 Implementation of comprehensive hospital total participants. Because the literature related to Jointjoint arthroplasty programs and clinical pathways Camp–type programs is so limited, additionalmay also alter orthopedic surgeons’ TKA rehabili- studies exploring effectiveness of comprehensivetation protocols, in addition to reducing length of rehabilitation programs are needed, especially inhospital stays. The Joint Camp program is an patient satisfaction, after total hip arthroplasty andexample in that it does not include the use of in relation to other specific clinical outcomes.CPMs postoperatively for TKA rehabilitation. The Implant position and balancing, and use ofuse of CPM remains controversial in the literature computer-assisted surgery may be other factors,[6,15-17]. We found that the use or nonuse of the which may influence clinical outcomes related toCPM did not seem to make a difference in average accelerated hospital stays and warrant furtherknee range of motion between the Joint Camp study; therefore, postoperative radiographic align-group and the non–Joint Camp group by 6 weeks ment as measured by the Knee Society radio-after surgery. The fact that CPM was not used in graphic scores should be included in futureJoint Camp and the length of stay was still shorter research in this area.bears notice, especially in light of the lack of In summary, this study demonstrates that reha-increase in manipulations in Joint Camp patients. bilitation outcomes in the 12 months after primary This contrasts with Mauerhan et al , who unilateral TKA as measured by Knee Society scoresexpress the concern that decreased PT exposure  and range of motion were not compromised bydue to decreased length of stay, with CPM use, participation in a hospital program which, reducedmay be a contributing factor to impaired func- length of stay.tional range of motion in the 6-week postopera-tive period. Of particular interest, patients in the Joint Camp Acknowledgmentsgroup did not experience more inpatient or outpa-tient complications or readmissions because of Kathie Hummel-Berry, PhD, PT, is acknowledgedchanges in immediate postoperative care and for her assistance with the study design. Kevinshorter length of hospital stay. The number of Ching, SPT; Pamela Drake, SPT; and Lori Hassell,cases with wound healing complications and SPT, of the University of Puget Sound Physicalarthrofibrosis with the need for knee manipulation Therapy Program, Tacoma, Wash, are acknowl-also did not increase. With the initiation of Joint edged for their assistance in data entry for this study.Camp and surgeries regularly performed on Mon- Kathy Bressler, MN, ONC, and Debi Williams, RN, ofdays, we were able to discharge most of our the Franciscan Health System, Tacoma, Wash, arepatients before the weekend, which also eased the also acknowledged for their assistance and support.burden of weekend hospital coverage. Outpatientmanagement of TKA patients after discharge to Referenceshome from any setting was not impacted or alteredby shortened length of hospital stay. 1. National Institutes of Health. National Institutes of We identified several limitations of this study. Health Consensus Development Conference on TotalAccording to our inclusion criteria, subjects had to Knee Replacement, December 8-10, 2003. http://have postoperative Knee Society scores  from at www.consensus.nih.gov/cons/117/117cdcstatement.least 2 of the 3 time intervals measured; not all htm [Retrieved Dec 13].charts had all 3. Therefore, the numbers of scores 2. American Association of Orthopedic Surgeons:compared between groups were not equal. Because Appendix D. Projection of total hip and total kneeall surgeries were performed by the same surgeon in arthroplasty procedures: average series to 2030.a single hospital, one form of bias, that of difference http://www.aaos.org/wordhtml/pdfs _ r/tjr.pdfin skill, was eliminated. However, although bias is [Retrieved April 23, 2003].reduced, so is generalizability. The study design of a 3. Hypnar LA, Anderson L. Attaining superior outcomessingle surgeon and single institution may represent with joint replacement patients. J Nurs Adm 2001; 31:544.most surgeons and institutions wherein primary 4. Healy WL, Iorio R, Ko J, et al. Impact of costlower extremity arthroplasty is being done in the reduction programs on short-term patient outcomeUnited States. and hospital cost of total knee arthroplasty. J Bone Further research is needed to determine all of Joint Surg Am 2002;84-A:348.the benefits that comprehensive total joint arthro- 5. Insall JN, Dorr LD, Scott RD, et al. Rationale of theplasty programs have to offer after discharge and Knee Society clinical rating system. Clin Orthopfor different populations of total joint arthroplasty 1989;13.
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