- Research article
- Open Access
- Open Peer Review
Reconstruction versus conservative treatment after rupture of the anterior cruciate ligament: cost effectiveness analysis
© Farshad et al; licensee BioMed Central Ltd. 2011
- Received: 16 November 2010
- Accepted: 19 November 2011
- Published: 19 November 2011
The decision whether to treat conservatively or reconstruct surgically a torn anterior cruciate ligament (ACL) is an ongoing subject of debate. The high prevalence and associated public health burden of torn ACL has led to continuous efforts to determine the best therapeutic approach. A critical evaluation of benefits and expenditures of both treatment options as in a cost effectiveness analysis seems well-suited to provide valuable information for treating physicians and healthcare policymakers.
A literature review identified four of 7410 searched articles providing sufficient outcome probabilities for the two treatment options for modeling. A transformation key based on the expert opinions of 25 orthopedic surgeons was used to derive utilities from available evidence. The cost data for both treatment strategies were based on average figures compiled by Orthopaedic University Hospital Balgrist and reinforced by Swiss national statistics. A decision tree was constructed to derive the cost-effectiveness of each strategy, which was then tested for robustness using Monte Carlo simulation.
Decision tree analysis revealed a cost effectiveness of 16,038 USD/0.78 QALY for ACL reconstruction and 15,466 USD/0.66 QALY for conservative treatment, implying an incremental cost effectiveness of 4,890 USD/QALY for ACL reconstruction. Sensitivity analysis of utilities did not change the trend.
ACL reconstruction for reestablishment of knee stability seems cost effective in the Swiss setting based on currently available evidence. This, however, should be reinforced with randomized controlled trials comparing the two treatment strategies.
- Anterior Cruciate Ligament
- Anterior Cruciate Ligament Reconstruction
- Anterior Cruciate Ligament Rupture
- Meniscal Lesion
- Tear Anterior Cruciate Ligament
Rupture of the anterior cruciate ligament (ACL) changes the kinematics of the knee  and often results in instability with accompanying functional disability and pain [2–22]. Although there are more than 2000 scientific articles in the literature  illuminating several aspects of ACL rupture, there is no consensus on the optimal treatment. Whereas some authors reported adequate outcomes after operative treatment using various techniques [8, 13, 24–44], others documented sufficient clinical results after conservative treatment with various protocols of immobilization and physiotherapy [4, 45–64]. Although several instruments and scoring systems [65–69] have been developed to facilitate standardized reporting and comparison of differently treated patients, decision towards one or the other, namely, conservative or surgical treatment seems currently challenging  due to lack of randomized controlled trials with information on long-term results .
Most surgeons advocate ACL reconstruction for patients with ACL rupture associated with subjective instability whereas some orthopedic surgeons routinely favor conservative treatment of ACL ruptures. Thus there is still controversy on this common injury with an estimated incidence of approximately 1500/100,000 person-years in Switzerland, 1200/100,000 person-years in New Zealand , and 3000/100,000 person-years in the United States . The occurrence of ACL ruptures depends on sex, age, and sports activities of those affected . The Swiss National Insurance System for Injuries (UVG), which covers half the Swiss population, provides around 200-250 million US dollars equivalent yearly for patients with ACL injuries, including 40% of direct treatment costs.
A critical evaluation of benefits and expenditures of the two treatment options so as to provide valuable information for treating physicians and healthcare policymakers is in progress. Technical arguments appear unable to determine superiority of one or the other strategy and complementary research using economic and public health approaches including assessment of quality of life, direct cost, and cost effectiveness is necessary. Although cost effectiveness would significantly affect the decision toward one or other strategy, such studies for this common injury are rare [73, 74]. A cost effectiveness analysis would allow rational allocation of limited resources and resolve an uncertainty that might potentially have been created by setting the focus on purely medical factors rather than economics aspects.
Gottlob et al  reported that in young adults in the United States, surgical treatment of ACL ruptures was more cost-effective than conservative treatment. However, due to lack of studies comparing the two treatment options in the same study groups at that time (1999) as well as more recent advances particularly in the surgical treatment of ACL ruptures, the results must be interpreted with caution and might not represent the current status. Although several authors aimed to compare surgical with conservative treatment [2–22], these reports are difficult to use for cost effectiveness analysis due to lack of necessary information and use of outdated surgical techniques. The purpose of the present cost-utility analysis was to identify the more cost effective treatment option for ACL ruptures in patients at an average age 30-35 years from the viewpoint of third party payers in the Swiss setting by the use of evidence created by studies comparing directly both treatment options in the same study population.
Literature review and extraction of effectiveness data
Compilation of available evidence and transformation to utility
Distribution of level of activities of a constructed population based on available studies after either operative or conservative treatment of torn ACL.
Activity level (Gottlob et al)
Patients with activity data (n)
Follow Up (months)
Finke et al (2001)
Diekstall et al (1999)
Kessler et al (2008)
Seitz et al (1994)
Finke et al (2001)
Diekstall et al (1999)
Kessler et al (2008)
Seitz et al (1994)
Cost data were based on average cost of treating patients with ACL ruptures at the Department of Orthopedic Surgery, Orthopaedic University Hospital Balgrist (University of Zürich, Switzerland). Hospitalization data were analyzed for 254 consecutive patients who underwent ACL reconstruction between 2005 and 2009. From those, the last 31 consecutive cases representing the cohort of 2009 were analyzed in detail. The data of the remaining 223 patients (2005-08) were used to assure that the cohort of 2009 was representative. For the outpatient portion of the treatment before and after ACL reconstruction and for conservative treatment the experts were asked to assess what kind of resources the average patient with torn ACL experiencing joint instability would use in what frequency. Both used resources and prices per unit of each resource were extracted from detailed cost statistics provided by Orthopaedic University Hospital Balgrist. Furthermore, experts were asked to provide names of typical patients for each of the surgical and conservative arm to validate the calculations that were derived from statistical analysis. In addition, cost data by the Swiss National Insurance for Accidents (UVG) were used to confirm the ability of our cost data to represent the average Swiss patient undergoing either surgical or conservative treatment for ACL rupture.
Total direct costs of operative and conservative treatment of a torn ACL.
costs per unit (USD)
Outpatient visit (15 min)
Xray (Knee, 3 views)
In-hospital stay and OR
low molecular heparin
16 days 1/day
16 days, 3/day
Outpatient visit (15 min)
X-ray (Knee, 3 views)
low molecular heparin
21 days, 1/day
21 days, 3/day
Prices per unit are documented in USD calculated by conversion of Swiss Francs (CHF) by a factor of 1.15 based on the exchange rate as of May 3, 2010.
A decision tree was constructed using the software Treeage Pro 2009 over a time horizon of 90 months based on the constructed study population (Table 1). In the surgical arm, patients undergoing ACL reconstruction without complications (osteoarthritis or meniscal lesions) were distributed to activity levels 0-V on the basis of currently available evidence (Table 1). The corresponding utility values were used for each class of activity. In 3.5% of patients, ACL-reconstruction failed and re-reconstruction was needed. For those patients the activity level was assumed one class lower than before failure, except patients in class 1 remained in the same class. The same approach was used for construction of the conservative arm with the according probabilities and utility value for each activity class. In the model 16% of conservatively treated patients required surgical ACL reconstruction. Other studies have shown even higher (up to 39%) need for ACL reconstruction in conservatively treated patients . The average costs of the surgical arm without complication were used for patients added to the costs of initial conservative therapy.
The probability of sequelae associated with ACL rupture for patients after ACL reconstruction was set at 34% on the basis of the retracted articles that could provide sufficient long-term information [8, 19]. From those 34%, the major fraction was osteoarthritis (86%) followed by meniscal lesions (14%). For patients who decided to undergo conservative treatment, the probability of developing complications was higher (77%). Their ratio of osteoarthritis to meniscal lesions, however, was not the same (74% and 26%). It was assumed that all complications needed to undergo surgical therapy and the costs of surgical therapy for meniscal lesions and osteoarthritis were added to those of ACL repair or conservative treatment in such cases. Patients with sequelae of each treatment method were assumed in activity class II.
Sensitivity analysis was performed to test the robustness of the model. The uncertainty for the assigned utility values to the activity classes was tested for robustness by Monte Carlo probabilistic sensitivity analysis by using 10,000 sets of parameter values randomly sampled from a normal distribution (normal distribution and standard deviations (SD) as gained from the literature). Parameters covered included all utility values. Furthermore, the incremental cost effectiveness was calculated for the worst-case assumption where no attention would be given to complications such as meniscal lesions and osteoarthritis.
Extraction of effectiveness data and compilation to utility
The available literature was sufficient to allow construction of a population of 384 patients (229 treated surgically and 155 conservatively) with a mean follow-up after surgical and conservative treatment of 89 months and 90 months, respectively. Using the transformation key based on the experts survey, level of activities could be assigned to patient groups of extracted articles (Table 1). The proportion of patients with high levels of activity (IV and V) was higher after surgical (70.7%) than conservative treatment (49.7%) (Table 1).
Direct costs were higher in surgically (9926 USD) than in conservatively treated patients (2535 USD). The main contributor to the cost of ACL reconstruction was in-hospital stay with a mean of 4.8 days (7391 USD) (Table 2). The costs of ACL reconstruction extracted and analyzed on the basis of data compiled by Orthopaedic University Hospital Balgrist overestimated as expected the values provided by the Swiss UVG, with 8673 CHF (7536 USD) for both surgically and conservatively-treated patients.
Incremental cost effectiveness analysis for reconstructive therapy of torn ACL.
Incremental Cost Effectiveness
In the worst-case scenario, not accounting for sequelae such as late meniscal lesions or development of osteoarthritis, the incremental cost effectiveness would be 68,715 USD/QALY for surgical treatment.
The decision whether to treat conservatively or reconstruct surgically a torn ACL has been debated throughout the history of knee surgery. The high prevalence and associated public health burden of torn ACL has led to continuous arguments in favor of one or the other strategy, which produced, however, no clear solution. Although thousands of studies have been published in regard to ACL , a critical evaluation of benefits and expenditures of both treatment options to provide valuable information for treating physicians and healthcare policymakers has not been performed . Here, we analyzed the cost effectiveness of the two procedures in the Swiss setting and found surgical reconstruction to be cost effective assuming the patient has from symptoms such as the knee giving way, pain, or instability.
The results of our analysis must, however, be interpreted with caution. First, the information of clinical outcome or effectiveness for each treatment approach was based on compiled data from reported studies. Efforts were made to review systematically the currently available literature (Figure 1) so as to find the most suitable sources of information. Although the retracted studies [5, 7, 13, 19] were potentially heterogeneous and were not randomized controlled trials, they did compare the two treatment strategies in the same experimental setting and provide sufficient outcome data for abstraction to utility values.
Second, the decision tree is a model only. On the other hand, sensitivity analysis showed a very robust model. The most sensitive determinant changing the incremental cost effectiveness for surgical therapy > 10 fold to 68,715 USD/QALY was removal of sequelae of torn ACL. This however is an unrealistic scenario [7, 19]. Changes in the kinematics of gait produced by a deficient ACL have been described to result in subsequent osteoarthritis relatively unrelated to whether a reconstruction has been performed [77, 78]. Meniscal lesions are commonly concomitant to ACL ruptures and also play a contributive role in development of osteoarthritis [79, 80]. ACL-deficient, conservatively treated patients do need more often surgical treatment for meniscal lesions [5, 7, 13, 19]. The results of studies that might describe no difference in sequelae for either treatment strategy should be interpreted with caution to a common limitation being a selection bias of patients with less severe injuries to the conservative arm of the study. Further, the severity of osteoarthritis should be considered in studying long-term results of both treatment options; while the overall rate of osteoarthritis might not significantly be related to the treatment procedure, more severe degeneration has been reported in patients undergoing conservative treatment . It is however unquestionable that some patients will benefit more from ACL reconstruction than others. How and when to select patients for surgery remain strongly disputed issues. Stratification regarding the need for surgery has not been possible in the current analysis because there are no uniform guidelines or consensus.
Third, the cost of the conservative arm seems underestimated. Although hospital infrastructure, administration, and organization costs were mainly covered by surgically treated patients with in-hospital stays, these are also significantly used by ambulatory patients such as those whose ACL is conservatively treated.
ACL reconstruction is cost effective. Our calculated incremental cost effectiveness of 4890 USD/QALY is in good agreement with the hitherto only available analysis performed by Gottlob et al (5857 USD/QALY) . However, although the results of this study might contribute to informed decision making for health policymakers, the individual situation of the patient must be respected when suggesting one or the other strategy.
The authors want to thank the orthopedic surgeons of Balgrist University Hospital for their contribution in regard to development of the transformation key.
- Van de Velde SK, Gill TJ, Li G: Evaluation of kinematics of anterior cruciate ligament-deficient knees with use of advanced imaging techniques, three-dimensional modeling techniques, and robotics. J Bone Joint Surg Am. 2009, 91 (Suppl 1): 108-114.View ArticlePubMedPubMed CentralGoogle Scholar
- Andersson C, Odensten M, Gillquist J: Knee function after surgical or nonsurgical treatment of acute rupture of the anterior cruciate ligament: a randomized study with a long-term follow-up period. Clin Orthop Relat Res. 1991, 255-263. 264Google Scholar
- Clancy WG, Ray JM, Zoltan DJ: Acute tears of the anterior cruciate ligament. Surgical versus conservative treatment. J Bone Joint Surg Am. 1988, 70 (10): 1483-1488.PubMedGoogle Scholar
- Daniel DM, Stone ML, Dobson BE, Fithian DC, Rossman DJ, Kaufman KR: Fate of the ACL-injured patient. A prospective outcome study. Am J Sports Med. 1994, 22 (5): 632-644. 10.1177/036354659402200511.View ArticlePubMedGoogle Scholar
- Diekstall P, Rauhut F: [Considerations for the indications for anterior cruciate ligament reconstruction. Results of conservative versus operative treatment]. Unfallchirurg. 1999, 102 (3): 173-181. 10.1007/s001130050390.View ArticlePubMedGoogle Scholar
- Fink C, Hoser C, Benedetto KP: [Sports capacity after rupture of the anterior cruciate ligament--surgical versus non-surgical therapy]. Aktuelle Traumatol. 1993, 23 (8): 371-375.PubMedGoogle Scholar
- Fink C, Hoser C, Benedetto KP: [Development of arthrosis after rupture of the anterior cruciate ligament. A comparison of surgical and conservative therapy]. Unfallchirurg. 1994, 97 (7): 357-361.PubMedGoogle Scholar
- Fink C, Hoser C, Hackl W, Navarro RA, Benedetto KP: Long-term outcome of operative or nonoperative treatment of anterior cruciate ligament rupture--is sports activity a determining variable?. Int J Sports Med. 2001, 22 (4): 304-309. 10.1055/s-2001-13823.View ArticlePubMedGoogle Scholar
- Frobell RB, Lohmander LS, Roos EM: The challenge of recruiting patients with anterior cruciate ligament injury of the knee into a randomized clinical trial comparing surgical and non-surgical treatment. Contemp Clin Trials. 2007, 28 (3): 295-302. 10.1016/j.cct.2006.10.002.View ArticlePubMedGoogle Scholar
- Hinterwimmer S, Engelschalk M, Sauerland S, Eitel F, Mutschler W: [Operative or conservative treatment of anterior cruciate ligament rupture: a systematic review of the literature]. Unfallchirurg. 2003, 106 (5): 374-379. 10.1007/s00113-003-0596-7.View ArticlePubMedGoogle Scholar
- Jerosch J, Schaffer C, Prymka M: [Proprioceptive abilities of surgically and conservatively treated knee joints with injuries of the cruciate ligament]. Unfallchirurg. 1998, 101 (1): 26-31. 10.1007/s001130050228.View ArticlePubMedGoogle Scholar
- Karanikas K, Arampatzis A, Bruggeman GP: [Conservative versus operative treatment after ACL-rupture: influence on the muscle strength capability of the lower extremity]. Sportverletz Sportschaden. 2005, 19 (1): 15-21. 10.1055/s-2004-813680.View ArticlePubMedGoogle Scholar
- Kessler MA, Behrend H, Henz S, Stutz G, Rukavina A, Kuster MS: Function, osteoarthritis and activity after ACL-rupture: 11 years follow-up results of conservative versus reconstructive treatment. Knee Surg Sports Traumatol Arthrosc. 2008, 16 (5): 442-448. 10.1007/s00167-008-0498-x.View ArticlePubMedGoogle Scholar
- Linko E, Harilainen A, Malmivaara A, Seitsalo S: Surgical versus conservative interventions for anterior cruciate ligament ruptures in adults. Cochrane Database Syst Rev. 2005, CD001356-2Google Scholar
- Meuffels DE, Favejee MM, Vissers MM, Heijboer MP, Reijman M, Verhaar JA: Ten year follow-up study comparing conservative versus operative treatment of anterior cruciate ligament ruptures. A matched-pair analysis of high level athletes. Br J Sports Med. 2009, 43 (5): 347-351. 10.1136/bjsm.2008.049403.View ArticlePubMedGoogle Scholar
- Meunier A, Odensten M, Good L: Long-term results after primary repair or non-surgical treatment of anterior cruciate ligament rupture: a randomized study with a 15-year follow-up. Scand J Med Sci Sports. 2007, 17 (3): 230-237.PubMedGoogle Scholar
- Odensten M, Hamberg P, Nordin M, Lysholm J, Gillquist J: Surgical or conservative treatment of the acutely torn anterior cruciate ligament. A randomized study with short-term follow-up observations. Clin Orthop Relat Res. 1985, 87-93. 198Google Scholar
- Scavenius M, Bak K, Hansen S, Norring K, Jensen KH, Jorgensen U: Isolated total ruptures of the anterior cruciate ligament--a clinical study with long-term follow-up of 7 years. Scand J Med Sci Sports. 1999, 9 (2): 114-119.View ArticlePubMedGoogle Scholar
- Seitz H, Chrysopoulos A, Egkher E, Mousavi M: [Long-term results of replacement of the anterior cruciate ligament in comparison with conservative therapy]. Chirurg. 1994, 65 (11): 992-998.PubMedGoogle Scholar
- von Porat A, Roos EM, Roos H: High prevalence of osteoarthritis 14 years after an anterior cruciate ligament tear in male soccer players: a study of radiographic and patient relevant outcomes. Ann Rheum Dis. 2004, 63 (3): 269-273. 10.1136/ard.2003.008136.View ArticlePubMedPubMed CentralGoogle Scholar
- Wittenberg RH, Oxfort HU, Plafki C: A comparison of conservative and delayed surgical treatment of anterior cruciate ligament ruptures. A matched pair analysis. Int Orthop. 1998, 22 (3): 145-148. 10.1007/s002640050228.View ArticlePubMedPubMed CentralGoogle Scholar
- Zysk SP, Refior HJ: Operative or conservative treatment of the acutely torn anterior cruciate ligament in middle-aged patients. A follow-up study of 133 patients between the ages of 40 and 59 years. Arch Orthop Trauma Surg. 2000, 120 (1-2): 59-64.PubMedGoogle Scholar
- Frank CB, Jackson DW: The science of reconstruction of the anterior cruciate ligament. J Bone Joint Surg Am. 1997, 79 (10): 1556-1576.PubMedGoogle Scholar
- Aglietti P, Buzzi R, Zaccherotti G, De Biase P: Patellar tendon versus doubled semitendinosus and gracilis tendons for anterior cruciate ligament reconstruction. Am J Sports Med. 1994, 22 (2): 211-217. 10.1177/036354659402200210. discussion 217-218View ArticlePubMedGoogle Scholar
- Almqvist KF, Willaert P, De Brabandere S, Criel K, Verdonk R: A long-term study of anterior cruciate ligament allograft reconstruction. Knee Surg Sports Traumatol Arthrosc. 2009, 17 (7): 818-822. 10.1007/s00167-009-0808-y.View ArticlePubMedGoogle Scholar
- Asik M, Sen C, Tuncay I, Erdil M, Avci C, Taser OF: The mid- to long-term results of the anterior cruciate ligament reconstruction with hamstring tendons using Transfix technique. Knee Surg Sports Traumatol Arthrosc. 2007, 15 (8): 965-972. 10.1007/s00167-007-0344-6.View ArticlePubMedGoogle Scholar
- Bach BR, Jones GT, Sweet FA, Hager CA: Arthroscopy-assisted anterior cruciate ligament reconstruction using patellar tendon substitution. Two- to four-year follow-up results. Am J Sports Med. 1994, 22 (6): 758-767. 10.1177/036354659402200606.View ArticlePubMedGoogle Scholar
- Harner CD, Olson E, Irrgang JJ, Silverstein S, Fu FH, Silbey M: Allograft versus autograft anterior cruciate ligament reconstruction: 3- to 5-year outcome. Clin Orthop Relat Res. 1996, 134-144. 324Google Scholar
- Hertel P, Behrend H, Cierpinski T, Musahl V, Widjaja G: ACL reconstruction using bone-patellar tendon-bone press-fit fixation: 10-year clinical results. Knee Surg Sports Traumatol Arthrosc. 2005, 13 (4): 248-255. 10.1007/s00167-004-0606-5.View ArticlePubMedGoogle Scholar
- Johnson RJ, Eriksson E, Haggmark T, Pope MH: Five- to ten-year follow-up evaluation after reconstruction of the anterior cruciate ligament. Clin Orthop Relat Res. 1984, 122-140. 183Google Scholar
- Jomha NM, Pinczewski LA, Clingeleffer A, Otto DD: Arthroscopic reconstruction of the anterior cruciate ligament with patellar-tendon autograft and interference screw fixation. The results at seven years. J Bone Joint Surg Br. 1999, 81 (5): 775-779. 10.1302/0301-620X.81B5.8644.View ArticlePubMedGoogle Scholar
- Kleipool AE, Zijl JA, Willems WJ: Arthroscopic anterior cruciate ligament reconstruction with bone-patellar tendon-bone allograft or autograft. A prospective study with an average follow up of 4 years. Knee Surg Sports Traumatol Arthrosc. 1998, 6 (4): 224-230. 10.1007/s001670050104.View ArticlePubMedGoogle Scholar
- Krych AJ, Jackson JD, Hoskin TL, Dahm DL: A meta-analysis of patellar tendon autograft versus patellar tendon allograft in anterior cruciate ligament reconstruction. Arthroscopy. 2008, 24 (3): 292-298. 10.1016/j.arthro.2007.08.029.View ArticlePubMedGoogle Scholar
- Levitt RL, Malinin T, Posada A, Michalow A: Reconstruction of anterior cruciate ligaments with bone-patellar tendon-bone and achilles tendon allografts. Clin Orthop Relat Res. 1994, 67-78. 303Google Scholar
- Liden M, Ejerhed L, Sernert N, Laxdal G, Kartus J: Patellar tendon or semitendinosus tendon autografts for anterior cruciate ligament reconstruction: a prospective, randomized study with a 7-Year follow-up. Am J Sports Med. 2007, 35 (5): 740-748. 10.1177/0363546506298275.View ArticlePubMedGoogle Scholar
- Liden M, Sernert N, Rostgard-Christensen L, Kartus C, Ejerhed L: Osteoarthritic changes after anterior cruciate ligament reconstruction using bone-patellar tendon-bone or hamstring tendon autografts: a retrospective, 7-year radiographic and clinical follow-up study. Arthroscopy. 2008, 24 (8): 899-908. 10.1016/j.arthro.2008.04.066.View ArticlePubMedGoogle Scholar
- Nyland J, Johnson DL, Caborn DN, Brindle T: Internal health status belief and lower perceived functional deficit are related among anterior cruciate ligament-deficient patients. Arthroscopy. 2002, 18 (5): 515-518. 10.1053/jars.2002.32217.View ArticlePubMedGoogle Scholar
- Pokar S, Wissmeyer T, Krischak G, Kiefer H, Kinzl L, Hehl G: [Arthroscopically-assisted reconstruction of the anterior cruciate ligament with autologous patellar tendon replacement-plasty. 5 years results]. Unfallchirurg. 2001, 104 (4): 317-324. 10.1007/s001130050734.View ArticlePubMedGoogle Scholar
- Ruiz AL, Kelly M, Nutton RW: Arthroscopic ACL reconstruction: a 5-9 year follow-up. Knee. 2002, 9 (3): 197-200. 10.1016/S0968-0160(02)00019-4.View ArticlePubMedGoogle Scholar
- Scranton PE, Bagenstose JE, Lantz BA, Friedman MJ, Khalfayan EE, Auld MK: Quadruple hamstring anterior cruciate ligament reconstruction: a multicenter study. Arthroscopy. 2002, 18 (7): 715-724. 10.1053/jars.2002.35262.View ArticlePubMedGoogle Scholar
- Shelbourne KD, Stube KC: Anterior cruciate ligament (ACL)-deficient knee with degenerative arthrosis: treatment with an isolated autogenous patellar tendon ACL reconstruction. Knee Surg Sports Traumatol Arthrosc. 1997, 5 (3): 150-156. 10.1007/s001670050043.View ArticlePubMedGoogle Scholar
- Strand T, Molster A, Hordvik M, Krukhaug Y: Long-term follow-up after primary repair of the anterior cruciate ligament: clinical and radiological evaluation 15-23 years postoperatively. Arch Orthop Trauma Surg. 2005, 125 (4): 217-221. 10.1007/s00402-004-0766-2.View ArticlePubMedGoogle Scholar
- Taylor DC, Posner M, Curl WW, Feagin JA: Isolated tears of the anterior cruciate ligament: over 30-year follow-up of patients treated with arthrotomy and primary repair. Am J Sports Med. 2009, 37 (1): 65-71.View ArticlePubMedGoogle Scholar
- Viola R, Vianello R: Intra-articular ACL reconstruction in the over-40-year-old patient. Knee Surg Sports Traumatol Arthrosc. 1999, 7 (1): 25-28. 10.1007/s001670050116.View ArticlePubMedGoogle Scholar
- Ahn JH, Chang MJ, Lee YS, Koh KH, Park YS, Eun SS: Non-operative treatment of ACL rupture with mild instability. Arch Orthop Trauma Surg.Google Scholar
- Barrack RL, Bruckner JD, Kneisl J, Inman WS, Alexander AH: The outcome of nonoperatively treated complete tears of the anterior cruciate ligament in active young adults. Clin Orthop Relat Res. 1990, 192-199. 259Google Scholar
- Bonamo JJ, Fay C, Firestone T: The conservative treatment of the anterior cruciate deficient knee. Am J Sports Med. 1990, 18 (6): 618-623. 10.1177/036354659001800611.View ArticlePubMedGoogle Scholar
- Buss DD, Min R, Skyhar M, Galinat B, Warren RF, Wickiewicz TL: Nonoperative treatment of acute anterior cruciate ligament injuries in a selected group of patients. Am J Sports Med. 1995, 23 (2): 160-165. 10.1177/036354659502300206.View ArticlePubMedGoogle Scholar
- Engebretsen L, Tegnander A: Short-term results of the nonoperated isolated anterior cruciate ligament tear. J Orthop Trauma. 1990, 4 (4): 406-410.View ArticlePubMedGoogle Scholar
- Goldstein J, Bosco JA: The ACL-deficient knee: natural history and treatment options. Bull Hosp Jt Dis. 2001, 60 (3-4): 173-178.PubMedGoogle Scholar
- Hawkins RJ, Misamore GW, Merritt TR: Followup of the acute nonoperated isolated anterior cruciate ligament tear. Am J Sports Med. 1986, 14 (3): 205-210. 10.1177/036354658601400305.View ArticlePubMedGoogle Scholar
- Kannus P, Jarvinen M: Nonoperative treatment of acute knee ligament injuries. A review with special reference to indications and methods. Sports Med. 1990, 9 (4): 244-260. 10.2165/00007256-199009040-00005.View ArticlePubMedGoogle Scholar
- Kostogiannis I, Ageberg E, Neuman P, Dahlberg L, Friden T, Roos H: Activity level and subjective knee function 15 years after anterior cruciate ligament injury: a prospective, longitudinal study of nonreconstructed patients. Am J Sports Med. 2007, 35 (7): 1135-1143. 10.1177/0363546507299238.View ArticlePubMedGoogle Scholar
- Lehnert M, Eisenschenk A, Zellner A: Results of conservative treatment of partial tears of the anterior cruciate ligament. Int Orthop. 1993, 17 (4): 219-223.View ArticlePubMedGoogle Scholar
- McDaniel WJ, Dameron TB: The untreated anterior cruciate ligament rupture. Clin Orthop Relat Res. 1983, 158-163. 172Google Scholar
- Muaidi QI, Nicholson LL, Refshauge KM, Herbert RD, Maher CG: Prognosis of conservatively managed anterior cruciate ligament injury: a systematic review. Sports Med. 2007, 37 (8): 703-716. 10.2165/00007256-200737080-00004.View ArticlePubMedGoogle Scholar
- Neuman P, Englund M, Kostogiannis I, Friden T, Roos H, Dahlberg LE: Prevalence of tibiofemoral osteoarthritis 15 years after nonoperative treatment of anterior cruciate ligament injury: a prospective cohort study. Am J Sports Med. 2008, 36 (9): 1717-1725. 10.1177/0363546508316770.View ArticlePubMedGoogle Scholar
- Neusel E, Maibaum S, Rompe G: [Results of follow-up of conservatively treated isolated fresh anterior cruciate ligament rupture]. Aktuelle Traumatol. 1993, 23 (4): 200-206.PubMedGoogle Scholar
- Neusel E, Maibaum S, Rompe G: Five-year results of conservatively treated tears of the anterior cruciate ligament. Arch Orthop Trauma Surg. 1996, 115 (6): 332-336. 10.1007/BF00420326.View ArticlePubMedGoogle Scholar
- Noyes FR, Mooar PA, Matthews DS, Butler DL: The symptomatic anterior cruciate-deficient knee. Part I: the long-term functional disability in athletically active individuals. J Bone Joint Surg Am. 1983, 65 (2): 154-162.PubMedGoogle Scholar
- Paar O, Magin MN: [Possibilities and limits of conservative management of cruciate ligament injuries]. Chirurg. 1995, 66 (11): 1050-1060.PubMedGoogle Scholar
- Rauch G, Wirth T, Dorner P, Griss P: [Is conservative treatment of partial or complete anterior cruciate ligament rupture still justified? An analysis of the recent literature and a recommendation for arriving at a decision]. Z Orthop Ihre Grenzgeb. 1991, 129 (5): 438-446. 10.1055/s-2008-1040270.View ArticlePubMedGoogle Scholar
- Satku K, Kumar VP, Ngoi SS: Anterior cruciate ligament injuries. To counsel or to operate?. J Bone Joint Surg Br. 1986, 68 (3): 458-461.PubMedGoogle Scholar
- Strehl A, Eggli S: The value of conservative treatment in ruptures of the anterior cruciate ligament (ACL). J Trauma. 2007, 62 (5): 1159-1162. 10.1097/TA.0b013e31805006e7.View ArticlePubMedGoogle Scholar
- Johnson DS, Smith RB: Outcome measurement in the ACL deficient knee--what's the score?. Knee. 2001, 8 (1): 51-57. 10.1016/S0968-0160(01)00068-0.View ArticlePubMedGoogle Scholar
- Lysholm J, Gillquist J: Evaluation of knee ligament surgery results with special emphasis on use of a scoring scale. Am J Sports Med. 1982, 10 (3): 150-154. 10.1177/036354658201000306.View ArticlePubMedGoogle Scholar
- Mohtadi N: Development and validation of the quality of life outcome measure (questionnaire) for chronic anterior cruciate ligament deficiency. Am J Sports Med. 1998, 26 (3): 350-359.PubMedGoogle Scholar
- Noyes FR, McGinniss GH, Grood ES: The variable functional disability of the anterior cruciate ligament-deficient knee. Orthop Clin North Am. 1985, 16 (1): 47-67.PubMedGoogle Scholar
- Tegner Y, Lysholm J: Rating systems in the evaluation of knee ligament injuries. Clin Orthop Relat Res. 1985, 43-49. 198Google Scholar
- Frobell RB, Roos EM, Roos HP, Ranstam J, Lohmander LS: A randomized trial of treatment for acute anterior cruciate ligament tears. N Engl J Med. 363 (4): 331-342.Google Scholar
- Gianotti SM, Marshall SW, Hume PA, Bunt L: Incidence of anterior cruciate ligament injury and other knee ligament injuries: a national population-based study. J Sci Med Sport. 2009, 12 (6): 622-627. 10.1016/j.jsams.2008.07.005.View ArticlePubMedGoogle Scholar
- Prodromos CC, Han Y, Rogowski J, Joyce B, Shi K: A meta-analysis of the incidence of anterior cruciate ligament tears as a function of gender, sport, and a knee injury-reduction regimen. Arthroscopy. 2007, 23 (12): 1320-1325. 10.1016/j.arthro.2007.07.003. e1326View ArticlePubMedGoogle Scholar
- Gottlob CA, Baker CL: Anterior cruciate ligament reconstruction: socioeconomic issues and cost effectiveness. Am J Orthop (Belle Mead NJ). 2000, 29 (6): 472-476.Google Scholar
- Gottlob CA, Baker CL, Pellissier JM, Colvin L: Cost effectiveness of anterior cruciate ligament reconstruction in young adults. Clin Orthop Relat Res. 1999, 272-282. 367Google Scholar
- Devlin N, Parkin D: Does NICE have a cost-effectiveness threshold and what other factors influence its decisions? A binary choice analysis. Health Econ. 2004, 13 (5): 437-452. 10.1002/hec.864.View ArticlePubMedGoogle Scholar
- Farshad M, Gerber C, Szucs T, Meyer DC: Determining utility values in patients with anterior cruciate ligament tears using clinical scoring systems. BMC Health Serv Res. 2011, 11: 182-10.1186/1472-6963-11-182.View ArticlePubMedPubMed CentralGoogle Scholar
- Chaudhari AM, Briant PL, Bevill SL, Koo S, Andriacchi TP: Knee kinematics, cartilage morphology, and osteoarthritis after ACL injury. Med Sci Sports Exerc. 2008, 40 (2): 215-222. 10.1249/mss.0b013e31815cbb0e.View ArticlePubMedGoogle Scholar
- Batiste DL, Kirkley A, Laverty S, Thain LM, Spouge AR, Holdsworth DW: Ex vivo characterization of articular cartilage and bone lesions in a rabbit ACL transection model of osteoarthritis using MRI and micro-CT. Osteoarthritis Cartilage. 2004, 12 (12): 986-996. 10.1016/j.joca.2004.08.010.View ArticlePubMedGoogle Scholar
- Cebesoy O: What are the risk factors in the development of osteoarthritis following ACL reconstruction?. Int Orthop. 2006, 30 (5): 431-10.1007/s00264-006-0163-2. author reply 432View ArticlePubMedPubMed CentralGoogle Scholar
- Kullmer K, Letsch R, Turowski B: Which factors influence the progression of degenerative osteoarthritis after ACL surgery?. Knee Surg Sports Traumatol Arthrosc. 1994, 2 (2): 80-84. 10.1007/BF01476477.View ArticlePubMedGoogle Scholar
- Mihelic R, Jurdana H, Jotanovic Z, Madjarevic T, Tudor A: Long-term results of anterior cruciate ligament reconstruction: a comparison with non-operative treatment with a follow-up of 17-20 years. Int Orthop. 2011, 35 (7): 1093-1097. 10.1007/s00264-011-1206-x.View ArticlePubMedPubMed CentralGoogle Scholar
- The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1472-6963/11/317/prepub
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.