Yassine Ochen, Marilyn Heng, Rolf H.H. Groenwold, R. Marijn Houwert
A BMJ editorial from 1999 stated: “Good surgeons know how to operate, better ones when to operate, and the best when not to operate.”  The benefits of surgical interventions should exceed the harm and risk associated with the treatment. However, recommendations for surgical treatment can differ between surgeons based on how they perceive these benefits and risks.  In the field of orthopaedic surgery, the debate about the necessity of surgical treatment was fuelled by two studies that evaluated meniscal tears and found no differences between surgical and non-surgical treatment.[3,4]
Randomised controlled trials (RCTs) are considered the highest level of evidence concerning the effects of medical treatment and are deemed superior to observational studies when it comes to the evaluation of treatment effects. [5,6] In order to improve our own clinical practice using best available evidence, our study group performed two RCTs of surgical treatments. During the first RCT we came across some of the difficulties of performing a RCT in our working field. We found that patients did not wish to be randomised and surgeons were reluctant to randomly assign a surgical procedure.  The second RCT was terminated early due to low inclusion rates, and lack of funding, although we did find a clinically relevant outcome after interim analysis. 
Given the challenges that we faced in conducting a RCT, we decided to perform meta-analyses, which included both RCTs and observational studies. All these meta-analyses evaluated outcome, comparing surgical and non-surgical treatment, for frequently encountered orthopaedic trauma topics. In general, treatment choice appeared to be driven by surgeons’ preference rather than patient characteristics, leading to a limited potential for confounding. The meta-analyses included midshaft clavicle fractures, proximal humeral fractures, flail chest or multiple rib fractures, and finally a meta-analysis on acute Achilles tendon ruptures, which has just been published in The BMJ. [9–11]
Previous meta-analyses, which have included only RCTs, have shown that operative treatment of acute Achilles tendon ruptures significantly reduces the risk of tendon re-rupture compared with nonoperative treatment.  However, operative treatment leads to a significant increase in other complications such as infection, deep vein thrombosis, and sural nerve injury.  With the addition of observational studies, resulting in substantially more data, our meta-analysis shows that re-rupture and complication rates are far lower than expected with surgery compared with previous meta-analyses, and differences between treatment groups appear to be small. These findings indicate that the benefits associated with operative treatment might not always exceed the harm and risk associated with surgical intervention. Therefore, nonoperative treatment may be an acceptable option for the management of acute Achilles tendon ruptures. Patients should be counselled about the benefits and risks of both treatment options and surgeons should know when not to operate.
Yassine Ochen is a PhD candidate at the department of Surgery, University Medical Centre Utrecht, Utrecht, the Netherlands. He is currently a research fellow at the department of Orthopaedic Surgery, Harvard Medical School Orthopaedic Trauma Initiative, Massachusetts General Hospital, Boston, United States of America.
Marilyn Heng is Assistant Professor of Orthopaedic Surgery at the department of Orthopaedic Surgery, Harvard Medical School Orthopaedic Trauma Initiative, Massachusetts General Hospital, Boston, United States of America.
Competing interests: None declared.
1 Knowing when not to operate. BMJ 1999;318:A.
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3 Sihvonen R, Paavola M, Malmivaara A, et al. Arthroscopic partial meniscectomy versus sham surgery for a degenerative meniscal tear. N Engl J Med 2013;369:2515–24. doi:10.1056/NEJMoa1305189
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7 van der Meijden OA, Houwert RM, Hulsmans M, et al. Operative treatment of dislocated midshaft clavicular fractures: plate or intramedullary nail fixation? A randomized controlled trial. J Bone Joint Surg Am 2015;97:613–9. doi:10.2106/JBJS.N.00449
8 Smeeing DPJ, Houwert RM, Briet JP, et al. Weight-bearing or non-weight-bearing after surgical treatment of ankle fractures: a multicenter randomized controlled trial. Eur J Trauma Emerg Surg Published Online First: September 2018. doi:10.1007/s00068-018-1016-6
9 Smeeing DPJ, van der Ven DJC, Hietbrink F, et al. Surgical Versus Nonsurgical Treatment for Midshaft Clavicle Fractures in Patients Aged 16 Years and Older: A Systematic Review, Meta-analysis, and Comparison of Randomized Controlled Trials and Observational Studies. Am J Sports Med 2017;45:1937–45. doi:10.1177/0363546516673615
10 Beks RB, Ochen Y, Frima H, et al. Operative versus nonoperative treatment of proximal humeral fractures: a systematic review, meta-analysis, and comparison of observational studies and randomized controlled trials. J shoulder Elb Surg 2018;27:1526–34. doi:10.1016/j.jse.2018.03.009
11 Beks RB, Peek J, de Jong MB, et al. Fixation of flail chest or multiple rib fractures: current evidence and how to proceed. A systematic review and meta-analysis. Eur J Trauma Emerg Surg Published Online First: October 2018. doi:10.1007/s00068-018-1020-x
12 Egger AC, Berkowitz MJ. Achilles tendon injuries. Curr Rev Musculoskelet Med 2017;10:72–80. doi:10.1007/s12178-017-9386-7