Court File and Parties

Court File No.: CV-14-238 Date: 2019-07-19

Ontario Superior Court of Justice

Between:

SIOBHAN O’NEILL-RENOUF and ROBERT RENOUF, Plaintiffs

• Paul J. Cahill and Meghan Walker, for the Plaintiffs

- and -

DR. MOHAMMED ASLAM IBRAHIM, Defendant

• Andrew Kalamut and Daniel Goudge for the Defendant

Heard: May 22-24, 27, 29 & 30, 2019

Reasons for Judgment

BALTMAN J.

Introduction

[1] In September 2012, Ms. O’Neill-Renouf (“Ms. O’Neill”) was 44 years old and married, with two children. She was generally in good health and physically active, which included playing hockey recreationally.

[2] However, likely due to childbearing, Ms. O’Neill was experiencing “stress urinary incontinence”, meaning that she suffered involuntary urine leakage upon coughing, sneezing or other physical exertion. This condition usually occurs because the pelvic floor muscles have been weakened through pregnancy and no longer provide enough support to the urethra, the tube that transmits urine from the bladder to the exterior of the body during urination.

[3] To address this problem, Ms. O’Neill underwent a Tension-Free Vaginal Tape (“TVT”) surgery. This procedure is designed to provide support for a sagging urethra so that it can remain closed, with no accidental release of urine during movement or exertion. The defendant urologist, Dr. Ibrahim, performed the surgery.

[4] The procedure is generally completed within an hour and the patient is released from the hospital within 24 hours, with minimal if any problems. Unfortunately, in this case, severe complications became evident immediately after the surgery. Ms. O’Neill awoke with extreme pain in her right thigh, which was later determined to be the result of an injury to her right obturator nerve. The obturator nerve is derived from the second, third and fourth lumbar nerves and supplies the muscles on the medial (inside) of the thigh. There are two relevant muscles directly adjacent to the obturator nerve: “obturator externus” and “obturator internus”.

[5] The injury to the obturator nerve has left Ms. O’Neill with permanent pain and physical limitations in her right hip and inner thigh. The parties have agreed on the amount of her damages but disagree on whether Dr. Ibrahim is liable for those damages.

[6] There is no dispute that Ms. O’Neill suffered an obturator nerve injury during the surgery. It is also not disputed that the injury to her obturator nerve is the cause of her damages. The issue is what caused the nerve injury.

[7] There are two competing theories in this case with respect to the mechanics of the obturator nerve injury. The plaintiff maintains that the likely cause of the injury is direct trauma to the obturator muscles and/or nerve, caused by the operative needle straying laterally outside of the surgical field.

[8] The defendant argues that Ms. O’Neill’s injuries have been caused by edema (swelling). He claims that the plaintiff developed edema immediately after the surgery, which tracked laterally to the obturator muscles and nerve, causing enough compression to result in an immediate nerve injury.

[9] Drilled down to its core, the issue is whether Ms. O’Neill’s injuries were caused by incorrect needle placement during the surgery or by edema tracking “naturally” from the surgical site.

[10] For the following reasons, I find the plaintiff’s theory to be the only reasonable explanation for Ms. O’Neill’s injuries, and therefore Dr. Ibrahim is liable for her damages.

[11] At numerous points in these reasons, significant portions of counsel’s written submissions have been reproduced, sometimes verbatim. Because of their frequency, I have not identified those occasions individually. That said, the reasoning in this decision is my own.

Legal Framework

[12] In an action for medical negligence, a plaintiff must prove, on a balance of probabilities, that the defendant breached the standard of care of a reasonable and prudent physician of the same experience and standing, having regard to all of the circumstances of the case. If, as here, the physician holds himself out to be a specialist, a higher degree of skill is required: Crits v. Sylvester (1956), 1 D.L.R. (2d) 502 (Ont. C.A.), at p. 508, aff’d , [1956] S.C.R. 991.

[13] That burden can be discharged through circumstantial evidence that leads to an inference of negligence, which then requires the defendant to offer an explanation to negate the inference of negligence. If the defendant produces a reasonable explanation that is at least as consistent with no negligence, this may neutralize the inference of negligence. The strength of the explanation the defendant must provide must match the strength of the inference of negligence that arises from the plaintiff’s case. Further, just as the inference advanced by the plaintiff must arise from the evidence, so, too, must the explanation offered by the defendant be grounded in the evidence: Hassen v. Anvari, [2003] O.J. No. 3543 (C.A.), at para. 9, leave to appeal to SCC refused, [2003] S.C.C.A. No. 490; Austin v. Bubela, 2011 ONSC 1958, at paras. 13, 43, 46; and Chasse v. Evenson et al., 2006 ABQB 342, 399 A.R. 121, at paras. 60-61.

[14] Moreover, evidence showing the exercise of unreasonable care during the course of surgery must be taken from the totality of the evidence, in particular in situations of circumstantial evidence where the surgeon is unable to explain the cause of the injury: Carlsen v. Southerland, 2008 BCSC 1772, at para. 24.

[15] Finally, the court should not use an unfortunate outcome as the barometer of negligence. It is an error to focus on the result rather than the means: St-Jean v. Mercier, 2002 SCC 15, [2002] 1 S.C.R. 491, at para. 53. Thus, in this case, that Ms. O’Neill was left with permanent physical injuries as a result of the TVT surgery is not determinative of whether Dr. Ibrahim fell below the standard of care.

The Issue in this Case

[16] It is undisputed that to succeed in a claim of medical negligence, a plaintiff must prove the following four elements on a balance of probabilities:

a. The defendant owed a duty of care to the plaintiff; b. The defendant breached the standard of care established by law; c. The plaintiff suffered injury or loss; and d. The defendant’s conduct caused the injury.

[17] In this case, the first and third elements are conceded: it is undisputed that Dr. Ibrahim owed Ms. O’Neill a duty of care, and it is clear that she has suffered an injury to her obturator nerve.

[18] The real dispute is whether there was a breach of the standard of care by Dr. Ibrahim in the performance of the surgery, and if so, whether this breach caused injury to Ms. O’Neil.

[19] In this case, that boils down to a single question. Both the plaintiff’s and the defendant’s expert urologists agree that it would be a breach of the standard of care for a surgeon to cause direct injury to the obturator nerve and muscles during this surgery. The obturator nerve and the obturator muscles are outside the surgical field, and the needle should not stray that far laterally so as to involve these structures.

[20] Therefore, counsel agree that both the issues of standard of care and causation are effectively answered by making a determination as to how the nerve and muscles were likely injured. In other words, did Dr. Ibrahim misdirect the needle such that it caused direct trauma to the obturator nerve or muscles OR are Ms. O’Neill’s symptoms attributable to edema from the normal course of surgery?

[21] That is a question of fact based on the evidence. In addition to Dr. Ibrahim’s testimony and various medical records that were filed, I heard from four experts: Drs. Casey and Stewart (for the plaintiff) and Drs. Carr and Bril (for the defendant).

Overview of the Evidence

The Procedure

[22] In TVT surgery, the patient is first placed in the “lithotomy” position, namely on her back with the hips and knees flexed and the thighs apart.

[23] After various preparatory steps, including marking the exit sites above the pubic bone, the surgeon inserts a mesh tape and places it under the urethra like a sling or hammock, to keep it in its normal position. The tape is inserted by two needles that pass through the vaginal tunnel and exit above the pubis, one on each side. The tape is secured through small incisions in the abdomen and vaginal wall.

[24] The procedure can be performed under local or general anaesthetic. In this case, it was the latter. Either way, the patient usually leaves the hospital the same day or the following day.

The Surgery in this Case

[25] The surgery in this case proceeded on September 26, 2012, at Brampton Civic Hospital.

[26] The surgery began at 10:57 a.m.

[27] Dr. Ibrahim likely passed the operative needle on Ms. O’Neill’s right side around 11:25.

[28] The surgery ended at 11:50.

[29] Anaesthesia was finished at 11:55 and Ms. O’Neill arrived in the post-op recovery room at 11:57.

[30] Immediately after the procedure, Dr. Ibrahim dictated an operative note reflecting a completely uneventful surgery.

[31] At 12:00 p.m., Ms. O’Neill is noted to have right groin pain, which she is unable to rate by scale, on arrival to the recovery room.

[32] At 12:30, Ms. O’Neill is noted to have pain on the entire right thigh with associated muscular cramping.

[33] At 13:00, Ms. O’Neill is again noted to have pain on the entire right thigh associated with muscular cramping. She is further noted to have facial grimaces, to be tense/rigid/clenched and to be reporting pain of 7 of 10. The onset of pain is noted to be on arrival to recovery.

[34] At 13:15, Ms. O’Neill is again noted to have pain on the entire right thigh associated with muscular cramping. She is further noted to have facial grimaces, to be tense/rigid/clenched and to be in pain of 5-6 of 10. The onset of pain is noted to be on arrival to recovery.

[35] At 14:00, it is noted that Dr. Ibrahim has been alerted to Ms. O’Neill’s ongoing complaints of severe right muscle spasms.

[36] Dr. Ibrahim assessed Ms. O’Neil at around 15:00 and found, among other things, difficulty with adduction. “Adduction” is the movement of the leg inward, toward the body, and is a motor function specific to the obturator nerve.

[37] Dr. Ibrahim then engaged various specialist consultations and radiologic investigations, some of which will be discussed below.

The Expert Evidence

Dr. Richard Casey (Urologist)

[38] Dr. Casey is the chief of urology at Halton Healthcare Services, a 600-bed hospital in Oakville. Because he has a particular interest in incontinence, he is often referred cases where complications arise during TVT surgery, which he is then asked to repair. Although in recent years he has referred TVT operations to another colleague in his hospital, as of 2012, when this incident occurred, he had performed approximately 200 TVT operations himself.

[39] Dr. Casey is of the opinion that the operative note as dictated by Dr. Ibrahim is not consistent with the post-operative findings and the subsequent radiologic findings. He believes that Dr. Ibrahim strayed from the midline, and instead of going straight up and down, he went lateral and poked into the obturator muscle and nerve.

[40] Dr. Casey asserted that the operative note itself, as dictated by Dr. Ibrahim, fell below the standard of care:

[S]ince I feel it’s a direct result of the needle placement and – and I’ve been there, I’ve done the procedure. Sometimes you get lost and – and you bump into things and re-adjust yourself. And when we got lost laterally where these major blood vessels are, it’s always good to make a note, because you may not be the only surgeon looking after this patient. And that’s why we do operative notes, not just – so I feel that, having obviously ventured in that area, it should have been mentioned in the note. [Emphasis added.]

[41] Dr. Casey added that in his experience as a surgeon, the operative note often does not represent all of what happened in the operating room. It is frequently an “idealised version” of what occurred, and he is therefore skeptical that the note in this case contains all the details that it should.

[42] He further explained how some of this procedure is “blind”: once the needle has been inserted into the vaginal wall, the surgeon is tunneling his way upward behind the pubic bone mostly by feel and knowledge of anatomy. He relies on certain landmarks to guide him, such as the midline of the pubic bone, but on the way up he cannot see where his needle has gone.

[43] Dr. Casey concludes that there was improper needle placement, in part, because of the immediacy of the post-operative findings of obturator nerve damage:

And the reason I, I think that is because the symptoms were immediate. Immediate, upon waking up, there was obturator nerve signs and symptoms, and the only way this could have happened, to be so immediate, is if the injury had just happened. [Emphasis added.]

[44] The subsequent radiologic findings were also consistent with a misplaced operative needle. Dr. Casey pointed to the MRI of the pelvis of October 1, 2012, which identified asymmetric edema within the right obturator muscle, stating:

If it had been a generalised edema on both sides, then you might say this is a general process, but since it’s specific to the side where the suspected injury is, the first thing that will come to my mind would be this is related to the injury, and someone has been in that muscle group with an instrument or – or something. [Emphasis added.]

[45] And further:

This tells me that the findings are consistent with operative activity in the region of the obturator nerve, because you would have to trans – you’d have to go past the obturator nerve to get to the muscle. So it – it appears as though something was in the region of the obturator nerve and obturator externus muscle that may be responsible for the symptoms that we see. [Emphasis added.]

[46] Dr. Casey testified that in this case, it was “fairly straightforward” that Dr. Ibrahim poked the needle into not just the obturator nerve, but also into the obturator muscle:

[I]nstead of going straight up and down, [he] went lateral, and poked into the obturator muscle[.]

[A]nd I know that, because the obturator muscle was damaged five days later, and the only way that could have happened is if someone had touched or poked it. And there was a needle on the end of it, so he probably punctured it and it had some bleeding.

[47] The fact that there is no evidence of a separate exit site is of no real significance, as Dr. Casey explains:

So it’s entirely possible to be placing the needle, realise you’re in the wrong spot, and reposition the needle without exiting the abdomen. We’re looking at probably an 8-inch, 12-centimetre track, so that has nothing to do with – that’s the final thing you do.

[48] Dr. Casey asserted that an obturator nerve injury following a TVT surgery would not be expected to happen if the surgeon took reasonable care. It is therefore not a recognized complication. The recognized complications of this procedure, such as a bladder perforation, may happen even with appropriate care. However:

[T]o injure the obturator nerve, you need to stray significantly from the operative field. You need to make a mistake. And as much as surgeons would like recognised complications to include mistakes, they don’t. We can’t, we can’t have – we can’t make mistakes and say it’s a recognised complication.

So in my opinion, major nerve and vessel damage during a procedure where there’s clear guidelines, there’s clear operative field that’s accessible, is not a recognised complication. [Emphasis added.]

[49] Dr. Casey explained that the needle trocars (handles) are designed so that the surgeon can see if he has twisted his hand excessively, and therefore Dr. Ibrahim should have realized he had strayed far off course. He emphasized that the proper standard of care does not permit this degree of deviation:

The standard – I cannot accept that the standard of care would accept you deviating enough to cause a significant neurologic injury that can be permanent, and I, I suspect that most patients, when given that as a potential complication, would say I’ll wear diapers, please, or something else. I’m not going to risk my – so it’s not a complication that’s acceptable under any terms.

[50] Dr. Casey does not agree with the opinion of the defence experts, Drs. Carr and Bril, that the obturator nerve injury was caused by edema:

[I]t’s not a mechanism that I recognise as being, based on my experience with obturator nerve dissections in over 600 lateral prostatectomies. It’s not something we see in any pelvic surgery.

[T]hat type of edema doesn’t cause pressure enough to cause immediate pain.

[E]dema takes a while to occur. It doesn’t occur two minutes after, or five minutes, it takes hours to occur…. This was, pain was immediate, suggesting that the injury was immediate, and is not consistent with it being due to a slow process such as edema. [Emphasis added.]

[51] In sum, it is Dr. Casey’s opinion that Dr. Ibrahim breached the standard of care by straying significantly during the insertion of the needle. Moreover, if Dr. Ibrahim had directed the needle properly, Ms. O’Neill would not have suffered an injury to her obturator nerve.

Dr. Bruce Stewart (Neurologist)

[52] Dr. Stewart has been practising and consulting in the field of neurology for over 50 years. He currently has his own practice in Toronto where he both treats patients with neurological conditions and consults on behalf of parties involved in litigation.

[53] Dr. Stewart stated that in his entire medical career, he has never seen an obturator nerve injury caused by compression. He confirmed that Ms. O’Neill did not have any pre-existing neurological conditions that would explain her post‑operative neurological symptoms.

[54] Like Dr. Casey, he thought the abnormal pelvic MRI of October 1, 2012, was significant, as it demonstrated asymmetrical hyper-intense signal in the medial aspect of the right obturator externus muscle, which is extremely close to the obturator nerve. In his view, edema alone would not cause a failure in the adductor externus muscle; it would only cause some local pain in the pelvis.

[55] Also like Dr. Casey, he found the timing here very suggestive. Immediately after surgery, Ms. O’Neill reported difficulty with adduction of her right leg. Adduction of the leg is the only motor function that the obturator nerve supplies. Given the timing of the onset of symptoms related to the obturator nerve, it must be in some way related to what happened in the surgical procedure.

[56] Dr. Stewart strongly discounted the “edema theory”, for several reasons. First, the focal damage in the right obturator nerve is not consistent with edema spreading from a properly inserted needle. Focal edema nearly always comes from some sort of manipulation in the area. In this case, that would be surgical manipulation.

[57] Second, the very rapid onset of symptoms related to the obturator nerve is indicative of an immediate, acute injury. Dr. Stewart considers the timing here to be “crucial”. Edema is not a likely explanation for the immediate onset of symptoms that Ms. O’Neill experienced. Edema is tissue swelling due to some inflammatory process or injury, and thus it usually takes at least hours, maybe even a day or so, to develop.

[58] Third, there is ample space in the pelvis for the spread of new tissues, including hemorrhage or edema. Here, the MRI of the Pelvis shows only a small amount of edema, which is unlikely to cause any compression, much less damage to the obturator nerve:

Nerves don’t get damaged by edema, unless there is an enclosed space where the edema is so great that it’s going to cause damage, compress the nerve and cause damage. That space is ample here. There’s that spread of edema – and there’s not a lot of edema. You’ll note that it’s very localized. So that is what is described by the – the radiologist. So that in my opinion I don’t agree that edema would cause permanent damage to – immediate and permanent damage to the obturator nerve or any nerve, actually.

I don’t agree that it’s edema. [Emphasis added.]

[59] Fourth, Dr. Stewart has never seen an obturator nerve injury caused by compression in his entire medical career:

I’m sure that edema can be found to cause damage to nerves in certain areas but as I pointed out, the nerve is tough and in my practice I have never seen obturator nerve damage by definite evidence of long compression of that nerve. [Emphasis added.]

[60] Fifth, to the extent that edema would develop and track after a surgery, it would probably track downwards, because of gravity (since the patient is lying down), as opposed to laterally towards the obturator nerve.

[61] Sixth, the Addendum to the MRI of the pelvis conducted in January 2015 identifies “subtle edema” of the right obturator nerve over a segment measuring approximately 1.5 cm. Dr. Stewart found this a “highly significant” indicator of injury to the obturator nerve. He acknowledged that the radiologist identified the swelling as subtle, but attributed that to him being cautious.

[62] For all those reasons, Dr. Stewart concluded that Ms. O’Neill’s obturator nerve was damaged by direct surgical manipulation and cannot be attributed to edema.

Dr. Mohammed Ibrahim (Defendant)

[63] Dr. Ibrahim has no independent memory of this surgery and therefore relied entirely on the written record (particularly his operative note) and on his usual practice.

[64] Dr. Ibrahim identified four potential causes of obturator nerve injury:

a) Pelvic hematoma (ruled out by a CT scan performed that day); b) Direct injury to the nerve; c) Edema; and d) Positional (from lying in the lithotomy position during the surgery).

[65] Dr. Ibrahim testified that based on medical literature and his own experience, obturator nerve injury is recognized to occur even when the needle is passed in the “exact right spot”.

[66] He conceded, however, that he had never experienced an obturator nerve injury from a TVT surgery prior to this one, despite having performed about 500 of them. Moreover, he was not able to cite any medical literature to support his contention that obturator nerve injury occurs in correctly-performed surgeries.

[67] Despite it being a “recognized complication” in Dr. Ibrahim’s mind, he did not advise Ms. O’Neill of this risk:

Q. So it’s something that is recognised to happen, in any procedure, it could happen any time?

A. I agree, and you know, maybe I should have mentioned it. I did not. [Emphasis added.]

[68] Dr. Ibrahim agreed that if the surgery was done as he had dictated, the needle would not be passing in the area of the obturator nerve. The needle would be “quite a distance” from the obturator nerve.

[69] Dr. Ibrahim also agreed that it was theoretically possible that he could have strayed laterally a bit, realized it, and then repositioned the needle into the correct spot. However, he insisted that on this occasion, he had no concern about the trajectory of the needle and was “100 percent confident” that the tape was in the right spot.

[70] After assessing Ms. O’Neill shortly after the surgery, Dr. Ibrahim noted that she had difficult adducting her right leg. Dr. Ibrahim agreed that the obturator nerve is the only nerve that supplies motor function for adduction of the leg.

[71] Significantly, Dr. Ibrahim was not initially concerned with edema as a potential cause of the nerve injury:

Q. So at the time of making this note [within a few hours of the surgery], you were not concerned that edema may be causing any kind of nerve pathology?

A. Correct.

Q. Is that right?

A. Correct.

[72] In addition to ordering a pelvic CT to rule out a hematoma, Dr. Ibrahim’s first response to the surgical complication was to call upon a colleague urologist for a second opinion:

Q. … So at the time you were concerned, you were concerned about a nerve pathology of some kind, of the obturator nerve, but you weren’t sure how it was being affected; is that right?

A. That would be true, yes.

Q. Okay, and so you made a decision to rely on the expertise of another specialist in your hospital to help you understand this nerve pathology.

A. Yes.

Q. And the first specialist that you chose to assist you with understanding this nerve injury was another urologist; is that right?

A. Another urologist.

Q. And this is Dr. Mohseni?

A. That’s true.

Q. And you didn’t decide to consult with a neurologist first?

A. No.

Q. You consulted with a urologist first?

A. Correct.

Q. And Dr. Mohseni is a colleague of yours?

A. He is a colleague of mine, yes.

Q. You two practise together in the same hospital?

A. Sure.

Q. And does he have the same type of urology practise as you do?

A. Yes, I would say so.

Q. Does he do T.V.T. procedures?

A. Sure.

Q. Okay, and you were looking for an opinion on whether there was anything about the surgery that may be causing this complication; is that right?

A. Correct.

Q. And you would have told him that the surgery was completely uneventful; is that right?

A. Correct.

Q. And that you were 100 percent certain that the tape was in the right place, is that right?

A. Correct.

Q. So he would be trying to look for an explanation for this obturator nerve injury that would be consistent with a completely uneventful surgery; is that right?

A. Yes.

Q. And it was based on that that he produced the note that was reassuring that the problem with the obturator nerve had nothing to do with the surgery itself?

A. That’s what – that’s what his consultation note said.

[73] The futility of the consultation with Dr. Mohseni is evident from his clearly erroneous conclusion that her pain was unrelated to the surgery. Every other physician involved in this case, including Dr. Ibrahim and both defence experts, agree that Dr. Mohseni was wrong. In other words, the plaintiff’s pain has everything to do with the surgery.

[74] Despite being “100 percent certain” that the tape was properly placed, on September 27 (the day after the surgery), Dr. Ibrahim nevertheless asked radiology to confirm the placement of the tape. Dr. Ibrahim strongly denied that this request suggested a lack of confidence in the correct placement of the tape. However, he conceded that as the surgeon who performed the procedure, he was the only person that would have known if the tape and/or needle had been in the incorrect position. He also agreed that for the tape to be in the wrong position, the needle would have to have gone in the incorrect position.

[75] Dr. Ibrahim felt it unimportant to share with the other specialists trying to understand the cause of Ms. O’Neill’s problems that he was asking radiology for confirmation of proper placement of the tape:

Q. Did you tell any of the other doctors that were involved in trying to understand the complication, whether you were looking for confirmation of the position of the tape from radiology?

A. I’m not sure what the implication of that would have been anyway.

[76] Despite making the effort to ask radiology for confirmation about tape placement, the fact that he did not get an answer to his question was of no concern to Dr. Ibrahim:

And the fact that they didn’t answer specifically, it didn’t bother me, because I already know where the tape is anyway. It wasn’t that material. It’s not a significant issue for me.

[77] Dr. Ibrahim agreed that the MRI of October 1, 2012, confirmed there was trauma to the obturator nerve, although the cause was not identified.

Dr. Lesley Carr (urologist)

[78] Dr. Carr is a urologist with staff privileges at numerous hospitals, including Sunnybrook Health Sciences Centre, St. Michael’s Hospital and Women’s College Hospital. She has a subspecialty in female reconstructive urology and has been practising medicine since the mid-90s. As of 2012, she had performed a minimum of 500 TVT surgeries and had taught the procedure to residents.

[79] Dr. Carr opined that Dr. Ibrahim passed the needle properly, but somehow this caused edema that tracked out along the pelvic sidewall to involve the obturator muscles, which then caused sufficient pressure on the obturator nerve to result in the symptoms Ms. O’Neill complained of immediately after the surgery. She described this as an unfortunate and extremely rare complication of the procedure.

[80] Dr. Carr acknowledged that surgeons may not always document multiple passes of the needle in their operative note if the surgeon does not believe it to be a significant deviation.

[81] She testified that edema “generally starts milder, peaks maybe around 48 hours, 72 hours, and then starts to regress”.

[82] On cross-examination, Dr. Carr was asked to agree with the general proposition that a lateral deviation of the operative needle sufficient to touch the obturator nerve would be a breach of the standard of care. This surprisingly triggered a protracted exchange with counsel, during which she went from disputing the proposition, to qualifying it, to eventually conceding it. Specifically, she finally agreed that if the TVT surgery was done properly, there would be no injury to the obturator nerve through direct trauma. She further agreed that if the operative needle strayed to involve the obturator nerve and/or obturator externus muscle, that would be a breach of the standard of care.

[83] Given Dr. Carr’s agreement that a lateral deviation sufficient to impact the obturator nerve is a breach of care, the core assumption underlying her opinion in this case is that the needle did not deviate laterally to cause injury to the obturator muscle and/or obturator nerve. She agreed that this in turn requires her to “[come] up with an explanation as to how this outcome happened.”

[84] Dr. Carr agreed that it is possible for a surgeon to deviate laterally and not know that s/he has injured the obturator nerve during the actual procedure:

Q. But in terms of whether or not that deviation caused an injury to an obturator nerve, you wouldn’t know that until the patient came out of anesthesia.

A. Um, possibly not, no.

Q. Because you can’t see.

A. You can’t see it, no, absolutely.

Q. And because the patient is asleep and…

A. Yeah.

Q. … they can’t wake up and say, “Ouch”, right? So it’s certainly possible that you could deviate and perhaps in your mind not think it’s that significant, but it’s enough to cause injury to the obturator nerve and you don’t know it until the patient wakes up.

A. I think in general you would recognize that much of a deviation, but it’s a very fine line we’re talking.

THE COURT: Very fine…?

A. Fine lines.

[85] Dr. Carr testified that mesh tape would not appear on an MRI. She agreed that Dr. Ibrahim’s request for an MRI to visualize the mesh demonstrated a lack of knowledge on his part.

[86] Dr. Carr was unaware in giving her opinion that Dr. Ibrahim had asked for an MRI to confirm the proper placement of the mesh. During cross‑examination, she conceded that her opinion could be affected if there was some doubt in the surgeon’s mind about whether or not he may have strayed laterally, as evidenced by his request for confirmation of tape placement.

[87] Dr. Carr conceded that direct trauma to the obturator nerve by the operative needle is a “reasonable” and “documented” cause of obturator nerve injury, which would be consistent with a concern that the needle was placed laterally.

[88] Dr. Carr went on to agree that Dr. Ibrahim’s MRI requisition suggests some uncertainty on his part with respect to the placement of the operative needle:

Q. … You would agree with me the fact that Dr. Ibrahim is asking a radiologist to confirm the placement of the tape would indicate some question in his mind about the placement of the tape.

A. That would be my assumption from that, yeah.

Q. And it’s fair to say that if he was 100 percent certain that the tape was in the right place, he wouldn’t need to ask that question.

A. I think that’s true. I don’t think we can ever be 100 percent certain, but…

Q. Dr. Ibrahim was.

A. Okay.

Q. So would you agree with me that this does, to some degree, suggest some uncertainty on the part of the surgeon in terms of the placement of the tape?

A. I think he’s asking the question and he’s being thorough, but he’s asking the question, you’re right.

Q. Do you agree that it suggests some uncertainty on the part of the surgeon that the tape may not be in the right spot?

A. I can say that.

Q. Yeah.

A. Yeah.

Q. It’s true.

A. Yeah.

Q. And that’s, I think, an important thing to think about when we’re thinking about the cause of this injury, right? Is that fair?

A. Yeah.

[89] Dr. Carr accepted that the cause of the plaintiff’s post-operative pain (and hence her nerve injury) likely happened while that part of her body was being operated on; i.e. at 11:25 a.m.

Q. Okay. So whatever trauma caused the pain that she experienced when she came to at 12:00 p.m. could have happened at 11:25.

A. It’s reasonable.

Q. And in fact, probably did. Is that fair?

A. That’s fair.

[90] Dr. Carr agreed that direct nerve injury would be “entirely consistent” with a patient having immediate post-operative pain. She does not know how much edema is required to cause a nerve injury, but agrees that direct impact by a surgical needle will probably cause a nerve injury.

[91] Dr. Carr acknowledged that the medical literature documents obturator nerve injuries caused by direct trauma, but she could find no medical literature similar to her theory of injury, i.e. edema from a properly placed needle tracking laterally to cause immediate nerve injury.

[92] Dr. Carr agreed that if her theory regarding the mechanism of this injury was true, there would be more instances of it happening and it would be of interest to the academic community.

[93] Dr. Carr acknowledged that Dr. Mohseni, a fellow urologist, was the first specialist that Dr. Ibrahim consulted after he learned of the complication. As a urologist, Dr. Mohseni was not in a position to diagnose or treat a nerve injury. Having not been present during the surgery, Dr. Mohseni was not in as good a position as Dr. Ibrahim himself to know what happened during the surgery.

[94] Dr. Mohseni prepared a consultation note that concluded that the obturator nerve injury had nothing to do with the TVT surgery. Dr. Carr disagrees with this aspect of Dr. Mohseni’s opinion, as did all the other treating specialists that saw Ms. O’Neill subsequently.

[95] Dr. Carr recognized the concept of practising “defensive medicine”, which she agreed is where a doctor takes steps, in terms of patient care, to help defend themselves from civil litigation. She further agreed that both the Dr. Mohseni consultation and the MRI request for confirmation of tape placement contained a component of defensive medicine.

[96] Dr. Carr doesn’t know how widespread edema would have to be in order to compress a nerve. The edema within the obturator externus muscle could have been caused by surgical manipulation in that area. She agreed that although edema generally improves over time, in this case, Ms. O’Neill’s problems persisted for years after the surgery.

Dr. Vera Bril (Neurologist)

[97] Dr. Bril has been practicing neurology since 1980 and is the Director of Neurology at the University Health Network and Sinai Health System. She has a particular expertise in the diagnosis and management of patients with complex neuromuscular disorders and is widely published in that field.

[98] Dr. Bril opines that the likely cause of the obturator nerve injury was edema from the trauma of the TVT needle. This edema tracked in Ms. O’Neill’s pelvis, causing compression on the obturator nerve.

[99] She acknowledged that there have never been any medical studies documenting a case where pelvic edema, on its own, causes obturator nerve compression immediately after surgery. She also conceded that she does not know how much edema is necessary to cause nerve compression, nor can she confirm the exact origin of the edema in Ms. O’Neill’s pelvic region.

[100] Dr. Bril asserted that Ms. O’Neill likely did not suffer a direct nerve injury, because then she would not have improved “this rapidly”. In cross-examination, she was taken to clear evidence of ongoing nerve-related symptoms well beyond the resolution of the edema. Specifically:

• The June 18, 2013, (approximately nine months post-operation) MRI report demonstrating denervation atrophy; and
• The October 10, 2014, (over two years post-operation) symptoms of chronic right groin/inner thigh burning pain and ongoing use of Gabapentin (a medication for nerve pain).

[101] In response to this evidence, Dr. Bril raised the explanation that the temporary effects of nerve compression can cause lasting chronic pain symptoms in the brain. I will have more to say about this theory later. For now, I note that Dr. Bril conceded that “burning-type” pain is indicative of nerve pain and that the denervation atrophy observed by the radiologist is not from chronic pain.

Analysis

[102] As I set out above, the sole dispute in this case is what caused Ms. O’Neill’s nerve injury. Was it incorrect needle placement during the surgery, as the plaintiff maintains? Or was it edema tracking laterally from the surgical site, as the defence argues?

[103] My first task is to determine whether, on a balance of probabilities, Ms. O’Neill has established a prima facie case of negligence against Dr. Ibrahim.

[104] For the following reasons, I find that she has met this onus. There is substantial evidence that the obturator nerve and muscle was injured by a misplaced needle during the surgery:

a) The plaintiff had immediate post-operative pain involving her obturator nerve; b) The MRI of the pelvis dated October 1, 2012, demonstrated focal edema within the obturator muscle, which is the location of the obturator nerve; c) The plaintiff was only injured on the right side, signifying a difference in the surgical approach on this side; d) Direct nerve trauma is identified in the medical literature as a cause of nerve injury and is generally attributed to improper needle placement; and e) Even after the edema dissipated, Ms. O’Neill continued to experience neurological deficits related to her obturator nerve.

a) Immediate Post-Operative Pain

[105] Ms. O’Neill complained of significant pain within 35 minutes of the needle insertion, related specifically to her obturator nerve. As Dr. Breiner noted following his review on October 10, 2014, her symptoms “began immediately” after the surgery with “immediate onset of severe pain and burning”.

[106] Dr. Carr agreed that direct nerve injury would be “entirely consistent” with a patient having immediate post-operative pain.

[107] By contrast, edema generally starts off mild and takes at least 24-48 hours to peak. Therefore, if edema was the cause, one would not expect Ms. O’Neill to have pain and difficulty with adduction immediately post-operation. The most likely explanation for her symptoms immediately after the surgery is direct trauma to the nerve and muscle from the operative needle.

b) The MRI of October 1, 2012 (and September 28, 2012)

[108] The MRIs of the pelvis and spine showed focal edema within the obturator externus muscle and on the margin of the obturator internus muscle. There was also edema in the perineum and the paraspinal muscles.

[109] The operative needle would not have caused direct tissue damage to the perineum or paraspinal muscles, because they are too far away. This leaves only two other origin locations for the edema: the obturator externus and the margins of the obturator internus.

[110] Whether the edema resulted from a misplaced needle in the obturator externus muscle or was a direct injury from a misplaced needle in the obturator nerve, that amounts to a breach of the standard of care.

c) The Plaintiff was Only Injured on her Right Side

[111] Immediately after the surgery, Ms. O’Neill complained of pain on her right side. Her subsequent symptoms are all connected to an obturator nerve injury on her right side.

[112] At no point at all did she have problems on her left side.

[113] If the cause of her pain was generalized swelling, one would expect to see bilateral edema, not these asymmetric findings. The most logical explanation is that the operative needle strayed out of the surgical field on the right side, whereas it did not on the left.

d) The Plaintiff’s Mechanism of Injury is Supported by the Medical Literature

[114] Direct obturator nerve injury caused by a too laterally placed needle and tape is a known phenomenon and has been reported in medical journals.

[115] In a study titled “Obturator nerve injury: a rare complication of retropubic tension-free vaginal sling”, the authors examined a case where a woman had severe, sharp left hip and groin pain and thigh muscle weakness, worse on adduction, immediately after a TVT surgery. [1]

[116] On laparoscopy, one of the arms of the TVT mesh was found to pass through the internal obturator muscle, transecting the left obturator nerve. Because in this surgery the mesh follows the needle, the needle in this case would have passed through the internal obturator muscle, likely transecting the left obturator nerve. This is therefore evidence of a direct nerve injury causing immediate symptoms due to improper placement of the needle and mesh.

[117] The authors of this study caution surgeons:

During insertion, care should be taken to not advance the tape laterally so that structures such as the obturator nerve, and the iliac vessels are avoided.

[118] Similarly, in “Obturator nerve injury complicating a tension-free vaginal tape”, the authors state:

[T]here are rare but significant intraoperative complications which may result in significant morbidity, e.g. obturator nerve injury. Such injury has only been reported in two other studies, mostly caused by lateral placement of the tape. … [C]are must be taken not to insert the tape too laterally. … [T]he best way to prevent this serious complication is careful tape insertion with correct positioning. [2]

[119] If, as the defence maintains, unpredictable and widespread pelvic edema could lead to serious injury in TVT surgeries (or any other pelvic surgeries, for that matter), one would expect to find at least one study on point.

e) Even after the Edema Dissipated, the Nerve-Specific Complaints Remained

[120] If the Plaintiff’s neuropathy was caused by temporary compression, one would expect her nerve-related complaints to dissipate upon resolution of the edema.

[121] However, in this case there is concrete evidence of ongoing nerve‑related complaints:

a) The June 18, 2013, (approximately nine months post‑operation) MRI report demonstrating denervation atrophy; b) On October 10, 2014, (two years post-operation) chronic burning pain in the thigh and ongoing use of medication for nerve pain (Gabapentin); and c) The January 6, 2015, (approximately 28 months post‑operation) MRI report revealing subtle edema and swelling over a 1.5 cm segment of the obturator nerve.

[122] These ongoing nerve-related complaints years after the injury are more consistent with a direct nerve injury than a temporary compression of the nerve. Dr. Bril’s answer to that is that Ms. O’Neill developed a chronic pain condition, which explains the persisting complaints.

[123] But the evidence does not support “chronic pain” as a viable cause, for several reasons. First, Ms. O’Neill had no prior neurological history, and there is nothing in the record or in her history that suggests she is predisposed to chronic pain.

[124] Second, in the entire 353 page medical record relating to this case – spanning three and a half years – there are only two references to “chronic pain”, and on both occasions it is in the context of Ms. O’Neill reporting “burning pain” that has persisted in her right thigh since the surgery. [3] I find it highly significant that not one of the neurologists, urologists, radiologists, or other medical personnel that assessed or treated Ms. O’Neill throughout the years has ever suggested that the cause of her ongoing symptoms is chronic pain. The first – and only – physician to resort to that is Dr. Bril, despite never having examined or even met Ms. O’Neill.

[125] Third, Dr. Bril herself conceded that the denervation atrophy identified on the MRI of June 18, 2013, is not from chronic pain:

Q. But in terms of the, the development of denervation atrophy, it’s the same thing?

A. It – yes, it means…

Q. It’s not from chronic pain?

A. No.

Q. And that was my point, is this finding here, it’s not from chronic pain?

A. No.

The Defendant’s Edema Theory

[126] Having determined that Ms. O’Neill has made out a prima facie case of negligence, I must then go on to consider whether Dr. Ibrahim presented evidence to negate the prima facie case. In other words, has he advanced an explanation, grounded in the evidence, that matches the strength of the inference arising from the plaintiff’s case?

[127] In my view, Dr. Ibrahim’s edema theory fails to rebut the plaintiff’s case. It lacks both credibility and evidentiary support, for several reasons.

1. The Timing Doesn’t Align

[128] First and foremost, edema of this nature doesn’t happen immediately. According to the expert testimony, it takes up to 24-48 hours for edema to peak following trauma. Any swelling that would be present immediately following the surgery would be minimal. It therefore seems highly unlikely that edema is the cause of this injury.

2. The Location Doesn’t Align

[129] The MRI of October 1, 2012, showed swelling within the obturator externus muscle and on the margin of the obturator internus muscle.

[130] If the origin of Ms. O’Neill’s edema was in the retropubic space where the needle was supposedly placed, one would expect the edema to be found there, rather than localized to the obturator muscles.

3. Even the Surgeon Didn’t Suspect Edema

[131] Dr. Ibrahim was promptly alerted to the immediate reports of intense pain following the surgery. His very first reaction was to be “suspicious for an obturator nerve involvement which is extremely unusual”.

[132] Significantly, he himself did not initially consider edema as a potential cause. Instead, he thought the pain might be caused by a pelvic hematoma (bleeding), which was subsequently ruled out. He then, despite his testimony that he was 100 percent certain the tape was properly placed, requested an MRI to determine, among other things, the position of the tape in relation to the right pelvic wall structures.

[133] Dr. Carr testified that MRI cannot detect tape placement. She agreed that Dr. Ibrahim’s MRI request showed some insecurity on his part over whether he had indeed inserted the tape in the right spot, and that he engaged in “defensive medicine” after learning of the surgical complication.

[134] Why did Dr. Ibrahim not state in his operative note that he had difficulty navigating on the right side? There are two plausible explanations:

a) He strayed laterally but didn’t realize it at the time; or b) He strayed laterally, realized he was off course before the needle exited, and then corrected his path. Hopeful that he had corrected without any harm done to the patient, he chose not to include the detour in his operative note.

[135] Dr. Carr acknowledged that on occasion surgeons will, partway through the procedure, realize they are off course and re-position the needle. In those circumstances, they may not make note of any difficulty in the operative report.

4. The Defence Experts Prefer Speculation to Science

[136] The testimony of both Drs. Carr and Bril is speculative. Neither can say where the edema here originated. Each of them is unclear how quickly it would develop. And both physicians admitted they do not know how much edema is required and for how long to cause a significant injury to the obturator nerve.

[137] Significantly, neither of them, despite their vast years of practice and teaching, has ever seen or heard of a case where edema from TVT surgery caused a nerve injury.

[138] Nor have they ever read about it in the literature. The only literature produced to support their position involved a patient who developed a fibrotic reaction to the tape many months after the procedure. [4] All the experts here agreed that that study differed factually from Ms. O’Neill’s case. Moreover, Dr. Carr acknowledged that if patients were suffering obturator nerve injuries because of edema, despite properly placed needles, this would be of concern to the medical community and would likely appear in the urological literature.

[139] Most importantly, the one matter all the experts in this case do agree upon, both plaintiff and defence, is that direct impact by a surgical needle will very likely cause a nerve injury. In the battle between speculation and science, the latter must prevail.

[140] The flaws in the defence expert evidence may be explained by how their physicians approached this case. In my view, Dr. Carr exhibited unreasonable bias. Her extreme reluctance during cross-examination to concede the obvious undermines her reliability. I am referring to the very lengthy cross-examination before she would concede that if the operative needle strayed to involve the obturator nerve and/or externus muscle, that would be a breach of the standard of care. This is in contrast to Dr. Bril who, while opining that the needle here did not stray that far, conceded that if it did, it would constitute a breach.

[141] As for Dr. Bril, while she is clearly an experienced neurologist, she has never performed or assisted in this procedure. I also found that she was unreasonably selective in what evidence she relied upon. She refused to accept the validity of radiological findings that contradicted her position, despite not having reviewed the imaging herself or having any specialty training in radiology. I refer in particular to the June 18, 2013, MRI report demonstrating denervation atrophy, and the January 6, 2015, MRI report revealing subtle edema and swelling over a 1.5 cm segment of the obturator nerve.

Other Flawed Arguments by the Defence

[142] In his closing submissions, defence counsel raised certain arguments beyond what I have already addressed. In particular:

a) Dr. Casey “agreed” with Dr. Bril’s theory

[143] Defence counsel submits that during cross-examination, Dr. Casey accepted Dr. Bril’s theory as a reasonable explanation for the injury, in particular her assertion in her written report that the injury to the nerve was caused by muscle edema compressing on the nerve itself. Counsel relies in particular on this exchange:

Q. … So you, you agree, then that the injury to the nerve was caused by muscle edema compressing on the nerve itself?

A. No. I agree that it’s – her opinion is consistent with the injury that we observed. I didn’t say necessarily it was the primary, primary injury. I said what she – she makes sense, her reasons are reasonable, so I could not disagree that what she says makes sense, with the knowledge that she had.

Q. Okay, so…

A. She had no knowledge that there might have been a surgical trauma to the nerve, so her opinion is based on the knowledge that she has.

Q. Okay, so…

A. And it’s consistent with the injury.

Q. Now, if I were to tell you that Dr. Bril had the benefit reviewing all the reports that were exchanged as part of this litigation, and then still concluded that this was the case…. So Dr. Bril’s opinion that it’s muscle edema causing compression is consistent with the MRI findings and the neurological examinations. Do you agree that so far?

A. It’s consistent, yes.

[144] Defence counsel stops there. But to properly understand this exchange, the remaining portion of it needs to be considered.

Q. … So you agree that the likeliest cause of this injury…

A. No, I didn’t say likeliest, I said consistent with.

Q. No, Dr. Bril said it was the likeliest cause, and then you agreed with Dr. Bril.

A. I agreed that her opinion is consistent with the injury.

Q. So you’re saying that the cause is either muscle edema causing compression of the nerve, or a direct injury?

A. I’m saying that I, I can’t, I can’t take her to task on muscle – ‘cause it’s a possible mechanism of action. But Dr. Bril is not the surgeon, and is not privy to the, you know, the niceties of this procedure, so I would think that her opinion lacks the surgical knowledge necessary to make a wider opinion and maybe offer other options.

Q. Okay, so what I’m asking you, Dr. Casey, is what is the likely cause of the nerve injury itself?

A. The needle that was used to bring the…

Q. And did…

A. … the tape up, or the tape itself.

Q. Did it injure the nerve directly, or did it cause injury to the muscle, or did it – causing the – the edema causing the compression.

A. I don’t think, as I’ve stated, I don’t think the edema is, is likely the cause, because edema takes a while to form, and her presentation was immediate; okay? I can’t – I mean, this is not a very common injury and we don’t have a wealth of knowledge, you know, how this happens. But the timeline and the likely mechanisms of action suggests very strongly that it was a surgical injury. [Emphasis added.]

[145] When that exchange is read in its entirety, I disagree that Dr. Casey has accepted Dr. Bril’s theory as a reasonable alternative. At most, he has conceded that it is an opinion from a non-surgeon that, while consistent with the result, is not on the facts of the case a reasonable explanation for what caused the result.

[146] The defence theory is that the edema originated in the retropubic space and tracked laterally toward the obturator nerve and muscle. Nowhere in her report does Dr. Bril mention tracking edema as the cause. And that is not what defence counsel put to Dr. Casey in cross-examination. Counsel put to Dr. Casey the theory of edema in general causing compression, not edema tracking laterally from a properly placed needle.

[147] Moreover, to the extent that Dr. Casey conceded anything in this exchange, it was merely that while edema is a possible cause of the injury, it is not the likely one, whereas surgical error “very strongly” is the cause. As the Hassen case makes clear, for the defence to negate the inference of negligence, it must offer an explanation that is “at least as consistent with no negligence as with negligence”: at para. 9. This theory comes nowhere near that.

b) Dr. Tullio “Confirms” the Defence Theory

[148] On October 4, 2012, as part of her ongoing treatment by the neurology service, Ms. O’Neill was assessed by Dr. Gerald Tullio, a staff neurologist at Brampton Civic Hospital.

[149] Dr. Tullio’s assessment consisted of taking a history, reviewing the hospital records, conducting a physical examination of Ms. O’Neill, and neurodiagnostic testing (sensory nerve studies and an EMG). His consultation note was filed as a business record at trial.

[150] Dr. Tullio concluded that Ms. O’Neill “has evidence of an obturator muscle edema, and likely inflammation, as a result of her surgery.” He added that “there may be impingement, or involvement of the obturator nerve, causing adductor weakness on the right as well.”

[151] Defence counsel suggests that this is “consistent with the explanation of the cause of the injury” offered by Dr. Carr and Dr. Bril. It is nothing of the sort. All Dr. Tullio tells us is what everyone agrees; i.e. that Ms. O’Neill sustained an injury to her obturator nerve and muscle, resulting in edema in the area. That begs the question of how the injury occurred.

c) The Diagnostic Imaging “Contradicts” Direct Trauma

[152] Defence counsel asserts that the plaintiff’s theory of direct trauma by the operative needle is inconsistent with the diagnostic imaging. He referred in particular to various MRI reports of the pelvis, which showed edema in the soft tissue adjacent to the obturator internus muscle and in the perineum. Counsel argues that the plaintiff is prone to edema and edema is visible within the surgical field.

[153] Defence counsel also pointed to evidence from Dr. Bril to the effect that if there had been a direct injury to the obturator nerve, that would likely have shown up as a “bright” spot on the MRI.

[154] However, both those assertions were countered by both Drs. Stewart and Casey. Each of them explained that an injury to a nerve would likely not be visible on an MRI. That said, Dr. Stewart was strongly of the view that the asymmetric nature of the edema reported in the October 1 MRI – just days after the surgery – was a strong indicator of a direct injury to the obturator nerve. He added that edema, on its own, would not cause anything more than pelvic or abdominal pain. Here, where the patient demonstrated a failure in adduction immediately after surgery, the obvious inference is a direct injury to the obturator nerve. Dr. Stewart also thought the Addendum to the MRI conducted in January 2015, which reported “subtle edema and swelling of the right obturator nerve”, was “highly consistent” with an injury to the obturator nerve.

[155] The defence then points to Dr. Bril’s evidence that a direct injury to the obturator nerve would appear as fibrillations on an EMG; however, none of the studies in this case indicted that. Those results are neutral, at best. Both sides here agree there was an injury to the obturator nerve. Dr. Bril did not suggest that only a direct trauma to the nerve would produce an abnormal EMG result; if the needle impacted the obturator muscle, the resulting edema may well have compressed the nerve. Therefore the EMG studies in this case do not help determine the mechanics of the injury.

d) The Plaintiff is “Reasoning Backwards”

[156] During submissions defence counsel criticized the plaintiff’s approach as “reasoning backwards”. I disagree. The allegation of reasoning backwards usually occurs when a plaintiff assumes, simply by virtue of a bad outcome, that there must have negligence in the background. That is not this case. Like most allegations of medical negligence, while it is triggered by a bad outcome, the merits of the claim depend on the quality and weight of circumstantial evidence regarding the events that preceded the outcome. The defence criticizes this as working backwards but their own experts concede that the explanation for the nerve injury needs to be inferred from the history and the medical records. That is how plaintiff’s counsel presented his case and that is how I have assessed it.

e) The Plaintiff relies on Circumstantial rather than Direct Evidence

[157] Defence counsel further submitted that because there is “direct” evidence that the surgery was performed correctly, that must prevail over any “circumstantial” evidence to the contrary. To that I have two responses.

[158] First, there is no “direct” evidence of how this surgery was performed. Dr. Ibrahim’s operative note is not direct evidence. It is merely the written account he dictated after the surgery. He cannot verify it in court because, as he testified, he has no independent memory of this surgery. None of the nurses who were present testified and there is no videotape of the procedure.

[159] Moreover, the reliability of Dr. Ibrahim’s note is suspect. Despite noting that the surgery was “satisfactory” and “uneventful”, on the following day, Dr. Ibrahim asked radiology to confirm the placement of the tape. Dr. Carr agreed that this suggests he was questioning whether the tape was in fact correctly placed.

[160] Second, in any case it is completely incorrect at law to suggest that direct evidence is superior to circumstantial evidence. As Laskin J.A. observed in Bandur et al. v. Daiken et al., [1967] 1 O.R. 629 (C.A.), at para. 37:

The balance of probabilities as the yardstick of proof in civil cases is as applicable to a case built solely on circumstantial evidence as to one posited solely on direct evidence; and it is enough to call for its application that the circumstances in evidence yield inferences that are reasonably probative of the issues between the parties.

[161] In each case, whether the evidence is direct or circumstantial, it is a matter of weight for the trier of fact. In this case I have pointed to numerous pieces of circumstantial evidence which, viewed as a whole, strongly point to surgical negligence as the only reasonable conclusion. In particular:

• The plaintiff had immediate post-operative pain involving her obturator nerve and weakness of the muscles supplied by that nerve;
• The injury was solely on the right side;
• The MRI of the pelvis conducted on October 1, 2012, demonstrated damage to the right obturator muscle;
• The plaintiff has been left with permanent neurological deficits related to her right obturator nerve.

[162] By contrast, the defence theory basically comes down to this: within a mere 35 minutes of surgery, tracking edema from a properly placed needle caused a permanent nerve injury. But the mechanics of how that can happen are completely unexplained. Neither Dr. Carr nor Dr. Bril know how much edema is required to cause a nerve injury or even where it originated in this case. And the edema theory is unprecedented in the medical literature. Dr. Casey has never experienced it in over 200 surgeries. Dr. Carr has never seen it in her 500 surgeries. The defendant surgeon himself who performed it has never seen it in the hundreds of TVT procedures he had done, which may explain why it never even occurred to him as a possibility when the patient reported obturator nerve pain immediately after the surgery. This case is thus distinguishable from Jones‑Carter v. Warwaruk, 2019 ONSC 1965, at para. 282, where Quigley J. noted that “the plain availability in the obstetrical literature of a reasonable alternative explanation” led to a rejection of the plaintiff’s claim of negligence.

[163] In comparing the edema theory against the simple, obvious explanation of the needle straying, which all four experts admitted can cause this injury and which the medical literature clearly documents as a risk factor in this surgery, the plaintiff has clearly made out a claim for negligence on a balance of probabilities.

Conclusion

[164] The plaintiff’s claim is allowed. I urge the parties to resolve any issue regarding costs. If necessary, I may be approached.

Baltman J. Released: July 19, 2019

[1] Georgina Baines et al., “Obturator nerve injury: a rare complication of retropubic tension-free vaginal sling” (2016) 27:10 Intl. Urogynecology J. 1597.

[2] S.H. Lee et al., "Obturator nerve injury complicating a tension-free vaginal tape” (2003) 91 BJU Intl. 1 at 1.

[3] Clinical Records of Dr. A. Breiner, pp. 347, 352.

[4] R. Corona et al., “Tension-free Vaginal Tapes and Pelvic Nerve Neuropathy ” (2008) 15:3 J. Minimally Invasive Gynecology 262.