HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Figures Only Full Text (PDF) All Versions of this Article: 2382050063v1 238/3/863    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Boks, S. S. Articles by Bierma-Zeinstra, S. M. A. Search for Related Content PubMed PubMed Citation Articles by Boks, S. S. Articles by Bierma-Zeinstra, S. M. A.

Follow-up of Posttraumatic Ligamentous and Meniscal Knee Lesions Detected at MR Imaging: Systematic Review¹

¹ From the Department of Radiology, Rijnmond-Zuid Medical Center, Rotterdam, the Netherlands (S.S.B., D.V.); and Departments of General Practice (S.S.B., B.W.K., S.M.A.B.), Radiology (M.G.M.H.), and Epidemiology and Biostatistics (M.G.M.H.), Erasmus Medical Center, Rotterdam, the Netherlands. Received January 1, 2005; revision requested March 17; revision received April 17; accepted June 1; final version accepted June 1. Address correspondence to S.S.B., Duistere Steeg 4, 8051 ZR Hattem, the Netherlands (e-mail: s.boks{at}erasmusmc.nl).

	ABSTRACT

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

 
Purpose: To perform a systematic review of the literature regarding the natural course of ligamentous and meniscal knee lesions detected at magnetic resonance (MR) imaging.

Materials and Methods: The MEDLINE database was searched from January 1966 to February 2003. Studies were included if all of the following criteria were met: patients had collateral ligament, cruciate ligament, or meniscal lesions; MR imaging was performed in all patients; study included a group and/or subgroup of patients who underwent conservative treatment during follow-up; patients returned to the clinic for follow-up and clinical data or MR imaging outcomes were noted; and article was written in English, Dutch, German, French, Spanish, Italian, Swedish, Danish, or Norwegian. The quality of each study was assessed by using a standardized criteria set, and statistics were used to grade the level of agreement between the two reviewers. Studies with quality scores of 8 or more were designated as high quality. Results were compared with regard to study design and quality scores.

Results: The literature search identified 649 articles, and 11 studies (five on posterior cruciate ligament [PCL] injuries, five on anterior cruciate ligament [ACL] injuries, and one on meniscal injuries) met the inclusion criteria. No studies on the follow-up of collateral ligament injuries were identified. Four studies were of high quality, and the value for quality items was 0.80. Between 77% and 93% of the partial or complete PCL ruptures regained continuity. In cases of partial or total ACL rupture, repair of continuity was also possible. A possible association between MR imaging continuity and clinical stability was identified.

Conclusion: The ACL and PCL can regain continuity after partial or complete rupture. On the basis of this review, no conclusions can be drawn about the natural course of meniscal or collateral ligament injury seen at MR imaging.

© RSNA, 2006

	INTRODUCTION

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

 
Every year, many patients seek medical treatment for knee injury (incidence, 1.1%–1.4%) (1,2). Since the introduction of MR imaging, several researchers have reported on the appearance of normal and abnormal cruciate ligaments, collateral ligaments, and menisci. Compared with arthroscopy, which is considered the reference standard, magnetic resonance (MR) imaging has a high sensitivity and high specificity for demonstrating abnormalities in these structures (3–6). In their recent meta-analysis, Oei et al (6) described 79% sensitivity for lateral meniscal tears and 94% sensitivity for posterior cruciate ligament (PCL) tears. Specificity ranged from 88% for medial meniscal tears to 99% for PCL tears (6).

Treatment of posttraumatic knee lesions remains controversial, especially regarding conservative versus surgical treatment of cruciate ligament tears. The decision to reconstruct the injured ligament depends on many factors, including rupture severity, combined or isolated injury, physiologic skeletal maturity, activity level, and type and severity of symptoms (7–9). Satisfactory functional results have been reported in conservatively treated patients with PCL tears (10,11), and natural healing might occur in patients with anterior cruciate ligament (ACL) tears. Proponents of surgical treatment, however, report that fewer degenerative changes are seen following regained joint stability after surgery than are demonstrated with conservative treatment (12,13).

Because the functional outcome and healing process of knee lesions remain unclear, treatment remains controversial. MR imaging, however, allows noninvasive diagnosis and gradation of the severity of knee injury. To date, few researchers have reported on the sequential imaging of patients with knee injuries to establish whether changes in appearance occur during the early months of healing, and few have reported on the functional outcome (eg, athletic activity) of patients with knee lesions seen at MR imaging. Therefore, the purpose of this study was to perform a systematic review of the literature regarding the natural course of ligamentous and meniscal knee lesions detected at MR imaging.

	MATERIALS AND METHODS

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

 
Identification and Selection of the Literature
A search of relevant publications on the natural history of posttraumatic knee lesions detected at MR imaging was performed by two authors (S.S.B., S.M.A.B.). The search was conducted by using the MEDLINE database (from January 1966 to February 2003). The terms collateral ligament, cruciate ligament, and meniscus were linked by the Boolean operator OR. The Boolean operator AND was used to link the terms follow-up, knee, and MRI, which were linked to the previous set of terms (ie, collateral ligament, cruciate ligament, and meniscus) by using the Boolean operator AND. For each of the keywords, one or more synonyms were used (Appendix). The search was extended by screening the reference list of all relevant articles (S.S.B., S.M.A.B.). A study was considered eligible for inclusion if it fulfilled all of the following criteria: (a) Patients had collateral ligament, cruciate ligament, or meniscal lesions, (b) MR imaging was performed in all patients at baseline, (c) the study included a group and/or subgroup of patients who underwent conservative treatment during follow-up (no surgery for ligament reconstruction or meniscal debridement or repair), (d) after the initial diagnosis, patients returned to the clinic for follow-up, and clinical data or MR imaging outcomes were noted, and (e) the article was written in English, Dutch, German, French, Spanish, Italian, Swedish, Danish, or Norwegian.

Quality Assessment
Because variation in the internal validity of studies may influence the results and conclusions of a systematic review, the quality of each included study was assessed by using the following procedure. Two reviewers (S.S.B., S.M.A.B.) independently scored the quality of the selected studies by using a set of criteria that were previously published in the field of musculoskeletal disorders; these criteria were then modified for use in the topic of our review (Figure) (14). Items were given a binary score of 1 if a particular criterion was fulfilled, and items were given a binary score of 0 if a particular criterion was not fulfilled or if it was unclear whether the criterion was fulfilled. The final quality score of each study was based on the sum of the individual scores. In cases of disagreement, both reviewers discussed the scores to achieve a consensus.

View larger version (44K): [in this window] [in a new window] [Download PPT slide]   Set of criteria used by reviewers to assign quality scores for each of the included studies.

Data Extraction
Two authors (S.S.B., S.M.A.B.) extracted the main characteristics of each study—that is, study center, study design (retrospective or prospective), study population (consecutive patients, inclusion criteria, and number of participants), and follow-up period. Results from the different studies were also extracted and included descriptions of the initial lesions at MR imaging, clinical follow-up (patient complaints and physical examination results), MR imaging follow-up, and the association between MR imaging and clinical findings at follow-up.

Data Analysis
A statistic was used to rate the level of agreement between the two reviewers on each quality item, and studies were ranked according to their quality score. Because the observational studies in this review were considered to be heterogeneous with regard to follow-up, study population, and quality and outcome measures, we refrained from statistically analyzing the pooled data. Owing to the scarcity of data, the main statistic tool that was used was the analysis of counts and proportions. The statistic was estimated by using a commercially available software program (SPSS, version 11.0.1; SPSS, Chicago, Ill).

We compared the results of the different studies with regard to quality score (ie, high quality score [8 or greater] versus low quality score [less than 8]) and study characteristics.

	RESULTS

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

 
Characteristics of Identified Studies
The primary literature search identified 649 references. On the basis of the title and abstract, 31 articles were read completely. Of these, 10 articles met our inclusion criteria. After screening the reference lists, another study (on ACL lesions) was included, resulting in 11 articles. Of these, there were five studies on PCL injuries, five on ACL injuries, and one on meniscal injuries (15–25). No studies on the follow-up of collateral ligament injuries were identified. Nine articles were published in English, and two were written in Italian.

One study on ACL lesions included three different follow-up periods (21). Because each follow-up period had a different quality score, this study was ranked according to the highest score.

Regarding study characteristics, seven studies were retrospective and four were prospective. In these studies, the follow-up period ranged from 3 months to 11.6 years. All studies were hospital-based. The study population was generally small, and in eight studies less than 50 patients were included (Table 1).

The quality of the included studies was generally poor. Only four studies scored 8 or more of the 14 available quality points (Table 1). The shortcomings generally involved a poor description of symptoms or inclusion criteria for surgery, a retrospective study design, a small study size, and insufficient information owing to patients who were lost to follow-up.

PCL Injury
For the five studies on the natural course of PCL tears, the study population ranged from eight to 48 patients, and the quality scores ranged from 4 to 8 out of a maximum of 14 points (Table 1).

No conflicting results were found (Table 2). In total (all study results combined), 81 patients had partial or complete PCL ruptures. Regained continuity was observed on MR images and ranged from 77% (95% confidence interval: 46%, 95%) after 20 months of follow-up (18) to 93% (95% confidence interval: 80%, 98%) after 3.2 years of follow-up (17). In two studies, all continuous ligaments showed altered morphologic features (elongation) at follow-up (15,17). In another study, two of six PCLs with regained continuity showed focal intraligamenteous changes (19).

In only three studies was follow-up MR imaging correlated with complaints and/or function (15,18,19). Tewes et al (18) described no significant correlation between healing and clinical or functional status. In the study by Griffin et al (15), all eight patients (seven in whom the lesions regained continuity) were without complaints at follow-up. Bellelli (19) reported complaints in only five patients with instability; four of these patients demonstrated an abnormal PCL at follow-up. The five patients without instability showed natural repair of the PCL, but no reference was made to the subjective complaints in this group (19).

ACL Injury
For the five studies on the natural course of ACL tears, the study population ranged from 31 to 104 patients (Table 1). The quality score ranged from 3 to 12, with three studies scoring more than 8 points.

No conflicting results were found (Table 3). We refrained from pooling the results because of differences in rupture definitions and outcome measures. In one high-quality study concerning 50 complete ACL ruptures, researchers found a normal ACL in 21 (42%) of 50 patients (95% confidence interval: 28%, 57%) and a partial repair in 20 (40%) of 50 patients (95% confidence interval: 26%, 55%) at 3-month follow-up (21); at 11-month follow-up, results showed that further repair was possible. In another high-quality study on 31 partial ACL ruptures, researchers found a continuous ligament in 21 (68%) of 31 cases (95% confidence interval: 49%, 83%) at an average of 16.1 months follow-up (22). In low-quality studies, this healing capacity was also shown.

Meniscal Injury
In only one retrospective study did investigators report on the short-term follow-up of six meniscal lesions (25). Because successful conservative treatment was one of the inclusion criteria in that study, no conclusions can be drawn about the natural course of meniscal lesions on MR images.

	DISCUSSION

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

 
To our knowledge, our study is the first systematic review of the natural course of knee lesions detected at MR imaging. Although only 11 studies on this subject met our inclusion criteria and the quality scores were low, the results were generally consistent. Results of both high-quality and low-quality studies suggest that the PCL and the ACL can regain continuity after partial or total rupture. In cases of partial rupture or total rupture of the PCL, 77%–93% of the ligaments regained continuity after 6 months to 4.5 years of follow-up. Ruptured ACLs regained continuity in a slightly lower proportion of cases: 42% of complete ruptures regained continuity after 3 months and 68% of partial ruptures regained continuity after 6–36 months. There seems to be a weak association, however, between continuity at MR imaging and clinical stability at follow-up.

Oei et al (6) previously found that MR imaging is highly accurate in facilitating the diagnosis of meniscal and cruciate ligaments tears. In that study, no data on follow-up were used. In contrast, we were particularly interested in the natural course of such lesions.

We found only one study on conservatively treated meniscal injuries (25). However, because only six patients were followed up and because successful conservative treatment was one of the inclusion criteria in that study, we could not draw any conclusions on the natural history of meniscal injuries seen at MR imaging. A previous systematic review reported that there were no studies that described the conservative follow-up of meniscal injuries seen at arthroscopy or that compared conservative treatment with surgical treatment (26). Because all the retrieved follow-up studies on meniscal injuries in that review concerned surgically treated menisci, the natural history of meniscal injuries remains unclear (26).

A potential drawback of the present review might be the literature search. Although we used a sensitive set of keywords, we might have missed some relevant studies. Also, because our search was limited to indexed journals, unpublished studies and articles in nonindexed journals might have been missed. Finally, studies published in languages other than the nine we selected would have been missed.

The study population for each of the included studies was generally small, and seven studies used a retrospective study design. Moreover, poor data documentation in some studies interfered with the assessment of quality scores. Furthermore, the quality of the studies was generally poor; only four studies scored more than 8 quality points. Finally, because of heterogeneity in study design and data presentation, comparing the results was difficult, and quantitatively pooling the data was impossible. These factors hamper generalization of our results.

Results of previous studies on conservative treatment of acute ligament tears that were diagnosed with methods other than MR imaging (ie, with clinical examination or arthroscopy) showed a large variability in findings. Many authors described a satisfactory functional result after conservative treatment of the ACL tears, especially after partial rupture (27–32). Despite satisfactory to good functional results, there was often a reduction in activity and a change in the athletic performance of patients (27,29,32). Return to sports without functional disabilities in the majority of conservatively treated patients with PCL lesions is also described (33). Our results agree with those obtained in these studies. It seems that ruptured ligaments can regain continuity after conservative treatment in the majority of cases, which correlates with clinical stability.

We conclude that there is little knowledge on the association between the MR imaging appearance of ruptured cruciate ligaments, functional outcome scores, and complaints. For daily practice, it would be valuable to know whether there is a true association between normalization of MR imaging appearance and functional scores or whether the healing process seen at MR imaging predicts further functional recovery. If this is the case, one could choose to wait for follow-up MR imaging in eligible patients (patients with low functional demands and contraindications for surgery or patients who prefer to undergo conservative treatment) and to perform reconstruction only in cases of persisting abnormal MR imaging findings.

Further study with a longer follow-up period is needed to clarify the relationship between functional outcome, physical examination findings, and MR imaging results in patients with chronically injured knees. Clear data presentation is essential in order to judge the generalizability of the results. These studies should use a prospective study design, a clearly defined study population, a structured follow-up (including at least one physical and MR imaging examination), and an adequate follow-up period.

In conclusion, the ACL and PCL can regain continuity after partial or complete rupture. There is insufficient information on the natural history of collateral ligament and meniscal injuries detected at MR imaging.

	APPENDIX

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

 
For each of the keywords, one or more synonyms were used (Table A1).

	ADVANCES IN KNOWLEDGE

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

• The anterior and posterior cruciate ligaments can regain continuity after partial or complete rupture.
  
• There is a possible association between cruciate ligament continuity at follow-up and clinical stability at physical examination.
  
• There is little knowledge on the prognostic value of the MR imaging appearance of cruciate ligament rupture on functional outcome scores and complaints.
  
• No conclusions can be drawn about the natural course of meniscal or collateral ligament injury seen at MR imaging, because study results on this subject are sparse.
  

	FOOTNOTES

 

Abbreviations: ACL = anterior cruciate ligament • PCL = posterior cruciate ligament

Authors stated no financial relationship to disclose.

See also the other article by Boks et al in this issue.

Author contributions: Guarantor of integrity of entire study, S.S.B.; study concepts/study design or data acquisition or data analysis/interpretation, all authors; manuscript drafting or manuscript revision for important intellectual content, all authors; approval of final version of submitted manuscript, all authors; literature research, all authors; statistical analysis, S.S.B.; and manuscript editing, all authors

	References

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION APPENDIX ADVANCES IN KNOWLEDGE References

 

1. Kannus P, Jarvinen M. Incidence of knee injuries and the need for further care: a 1-year prospective follow-up study. J Sports Med Phys Fitness 1989;29:321–325.[Medline]
2. Van der Velden J, De Bakker DH, Claessens AAMC, Schellevis FG. Een nationale studie naar ziekten en verrichtingen in de huisartsenpraktijk. Basisrapport: morbiditeit in de huisartsenpraktijk. Utrecht, the Netherlands: Nederlands Instituut voor Onderzoek van de Eerstelijns gezondheidszorg (Nivel), 1991.
3. Cotten A, Delfaut E, Demondion X, et al. MR imaging of the knee at 0.2 and 1.5 T: correlation with surgery. AJR Am J Roentgenol 2000;174:1093–1097.[Abstract/Free Full Text]
4. Mackenzie R, Palmer CR, Lomas DJ, Dixon AK. Magnetic resonance imaging of the knee: diagnostic performance studies. Clin Radiol 1996;51:251–257.[CrossRef][Medline]
5. Vincken PW, ter Braak BP, van Erkell AR, et al. Effectiveness of MR imaging in selection of patients for arthroscopy of the knee. Radiology 2002;223:739–746.[Abstract/Free Full Text]
6. Oei EH, Nikken JJ, Verstijnen AC, Ginai AZ, Hunink MG. MR imaging of the menisci and cruciate ligaments: a systematic review. Radiology 2003;226:837–848.[Abstract/Free Full Text]
7. Dorizas JA, Stanitski CL. Anterior cruciate ligament injury in the skeletally immature. Orthop Clin North Am 2003;34:355–363.[CrossRef][Medline]
8. Janousek AT, Jones DG, Clatworthy M, Higgins LD, Fu FH. Posterior cruciate ligament injuries of the knee joint. Sports Med 1999;28:429–441.[CrossRef][Medline]
9. Shelbourne KD, Carr DR. Combined anterior and posterior cruciate and medial collateral ligament injury: nonsurgical and delayed surgical treatment. Instr Course Lect 2003;52:413–418.[Medline]
10. Fowler PJ, Messieh SS. Isolated posterior cruciate ligament injuries in athletes. Am J Sports Med 1987;15:553–557.[Abstract/Free Full Text]
11. Torg JS, Barton TM, Pavlov H, Stine R. Natural history of the posterior cruciate ligament-deficient knee. Clin Orthop Relat Res 1989;246:208–216.[Medline]
12. Clancy WG Jr, Shelbourne KD, Zoellner GB, Keene JS, Reider B, Rosenberg TD. Treatment of knee joint instability secondary to rupture of the posterior cruciate ligament: report of a new procedure. J Bone Joint Surg Am 1983;65:310–322.[Abstract/Free Full Text]
13. Richter M, Kiefer H, Hehl G, Kinzl L. Primary repair for posterior cruciate ligament injuries: an 8-year follow-up of fifty-three patients. Am J Sports Med 1996;24:298–305.[Abstract/Free Full Text]
14. Borghouts JA, Koes BW, Bouter LM. The clinical course and prognostic factors of non-specific neck pain: a systematic review. Pain 1998;77:1–13.[CrossRef][Medline]
15. Griffin LY, Burnett M, Milsap JH. Appearance of previously injured posterior cruciate ligaments on magnetic resonance imaging. South Med J 2002;95:1153–1157.[Medline]
16. Akisue T, Kurosaka M, Yoshiya S, Kuroda R, Mizuno K. Evaluation of healing of the injured posterior cruciate ligament: analysis of instability and magnetic resonance imaging. Arthroscopy 2001;17:264–269.[Medline]
17. Shelbourne KD, Jennings RW, Vahey TN. Magnetic resonance imaging of posterior cruciate ligament injuries: assessment of healing. Am J Knee Surg 1999;12:209–213.[Medline]
18. Tewes DP, Fritts HM, Fields RD, Quick DC, Buss DD. Chronically injured posterior cruciate ligament: magnetic resonance imaging. Clin Orthop Relat Res 1997;335:224–232.[Medline]
19. Bellelli A. Cicatrization of complete traumatic lesions of the posterior cruciate ligament: magnetic resonance follow-up of 10 cases and a proposal for modification of Gross classification [in Italian]. Radiol Med (Torino) 1998;95:286–292.[Medline]
20. Kocher MS, Micheli LJ, Zurakowski D, Luke A. Partial tears of the anterior cruciate ligament in children and adolescents. Am J Sports Med 2002;30:697–703.[Abstract/Free Full Text]
21. Ihara H, Miwa M, Deya K, Torisu K. MRI of anterior cruciate ligament healing. J Comput Assist Tomogr 1996;20:317–321.[CrossRef][Medline]
22. Fujimoto E, Sumen Y, Ochi M, Ikuta Y. Spontaneous healing of acute anterior cruciate ligament (ACL) injuries: conservative treatment using an extension block soft brace without anterior stabilization. Arch Orthop Trauma Surg 2002;122:212–216.[Medline]
23. Zugaro L, Catalucci A, Barile A, Di Cesare E, Masciocchi C. Anterior cruciate ligament tears in athletes: assessment and clinico-diagnostic control with a dedicated system [in Italian]. Radiol Med (Torino) 1998;96:198–203.[Medline]
24. Zeiss J, Paley K, Murray K, Saddemi SR. Comparison of bone contusion seen by MRI in partial and complete tears of the anterior cruciate ligament. J Comput Assist Tomogr 1995;19:773–776.[Medline]
25. Deutsch AL, Mink JH, Fox JM, et al. Peripheral meniscal tears: MR findings after conservative treatment or arthroscopic repair. Radiology 1990;176:485–488.[Abstract/Free Full Text]
26. Howell JR, Handoll HH. Surgical treatment for meniscal injuries of the knee in adults. Cochrane Database Syst Rev 2000;2:CD001353.[Medline]
27. Bak K, Scavenius M, Hansen S, Norring K, Jensen KH, Jorgensen U. Isolated partial rupture of the anterior cruciate ligament: long-term follow-up of 56 cases. Knee Surg Sports Traumatol Arthrosc 1997;5:66–71.[CrossRef][Medline]
28. Ciccotti MG, Lombardo SJ, Nonweiler B, Pink M. Non-operative treatment of ruptures of the anterior cruciate ligament in middle-aged patients: results after long-term follow-up. J Bone Joint Surg Am 1994;76:1315–1321.[Abstract/Free Full Text]
29. Bonamo JJ, Fay C, Firestone T. The conservative treatment of the anterior cruciate deficient knee. Am J Sports Med 1990;18:618–623.[Abstract/Free Full Text]
30. Messner K, Maletius W. Eighteen- to twenty-five-year follow-up after acute partial anterior cruciate ligament rupture. Am J Sports Med 1999;27:455–459.[Abstract/Free Full Text]
31. Neusel E, Maibaum S, Rompe G. Five-year results of conservatively treated tears of the anterior cruciate ligament. Arch Orthop Trauma Surg 1996;115:332–336.[Medline]
32. Sommerlath K, Odensten M, Lysholm J. The late course of acute partial anterior cruciate ligament tears: a nine to 15-year follow-up evaluation. Clin Orthop Relat Res 1992;281:152–158.[Medline]
33. Parolie JM, Bergfeld JA. Long-term results of nonoperative treatment of isolated posterior cruciate ligament injuries in the athlete. Am J Sports Med 1986;14:35–38.[Abstract/Free Full Text]

This article has been cited by other articles:

				L. S. Lohmander, P. M. Englund, L. L. Dahl, and E. M. Roos The Long-term Consequence of Anterior Cruciate Ligament and Meniscus Injuries: Osteoarthritis Am. J. Sports Med., October 1, 2007; 35(10): 1756 - 1769. [Abstract] [Full Text] [PDF]

				J. W. Schoones, S. S. Boks, and S. M. A. Bierma-Zeinstra Improving Literature Searches Radiology, April 1, 2007; 243(1): 301 - 302. [Full Text] [PDF]

This Article Abstract Figures Only Full Text (PDF) All Versions of this Article: 2382050063v1 238/3/863    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Boks, S. S. Articles by Bierma-Zeinstra, S. M. A. Search for Related Content PubMed PubMed Citation Articles by Boks, S. S. Articles by Bierma-Zeinstra, S. M. A.