On surgeon error and slipped cups

On the very useful and comprehensive Surface Hippy web site, there have been recent posts about slipped cups becoming a more common problem in hip resurfacing, with this problem being strictly surgeon error. Since in my academic research analysis of error is something I think about a lot, I feel the need to add a comment because of the way technical and everyday uses of the word "error" can cause confusion.

Nothing is definite and exact: all measurements and procedures will have error. Good engineering is about using the latest technology to construct something such that the error tolerances are way outside our day-to-day experience. So error is part of life in this world. Used in this way, 'error' is a value-neutral term.

If you think about all that's involved in a process like setting an acetabular cup (drilling, shaping, pounding, testing, bone quality....), some "error" is quite possible and can be expected. Experienced people will have lower error rates, but the complexity of the process and of the human body means that this rate can never be completely zero. To say it again: this rate can never be zero.

If I gave you 100 nails, and I just told you to pound them into a board, I bet you would get most of them into place, but I also bet you'd blow a few of your attempts at this very simple procedure: you'd make a few errors. A skilled person would make fewer mistakes. Anyone would in general make more mistakes if they were tired, rushed, or momentarily distracted, and fewer mistakes if they were really focused and practiced. All these are shades of gray between degrees of error.

My concern is that when people hear "surgeon error" they will tend to make the leap towards thinking "malpractice" or "incompetence" or "neglect" when they should just be hearing the value-neutral word, error. Clearly, if a surgeon has a complication rate way outside the norm, something might be up (assuming that the issue is in the operating room and not in patient selection, and that the numbers are high enough to be statistically valid). You really have to watch out for the latter - low to moderate-n statistics involving random error are really prone to runs and streaks: look at baseball as an example: with enough players randomly batting 250, a few players are always going to have a hitting streak going.

All surgeons go through training, and if hip resurfacing is to spread and help lots of people live better lives, lots of those people will be seeing surgeons who have done relatively fewer procedures. Instead, should they all, every one of them, go visit the handful of superstars who have done many hundreds of operations?

The tough thing for the prospective resurfacing patient is that you can't easily tell if you're surgeon is just riding an unlucky or a lucky streak, or if they are truly inept (or gifted). That is where high numbers do tend to help out. But you have to keep things in perspective, and beware of the human tendency to seek out zero risk - I'm sorry: but you cannot have that, because it does not exist. I think some realism and perspective is important, and at a time when you are already under stress and making lots of decisions, feeling pressed to hook up with a superstar might not be the most helpful thing, all other things considered.

I'm sure others might disagree.

Mending and on track...

Finding myself superstitious after the travails this hip has given me, I've been laying low, not wanting to jinx my recovery. But at this point, I've decided to emerge from my hideaway to give this report. 

My doctor has cleared me for full activity, provided I listen to my body and avoid extremes. I've ridden my road bike four times over the past 10 days, discovering mostly that I am now fat, slow, and out of shape. I also hiked up Mt. Cardigan in New Hampshire, about a 3 mile roundtrip hike with about 1000 feet of climbing on a moderately rough trial. Given all that and how I felt, I also stopped outpatient physical therapy this week, figuring that activity like I was doing plus some exercises at home would be fine, and save me some time and the healthcare system some money.

So, 75 days after the revision surgery to fix the slipped cup, things look good. I still get a little sore if I push it on the bike, or briskly mow the lawn (it's about 3.5 miles of walking on uneven terrain behind our wee little Neuton electric mower). But flexibility is good for the new hip and mostly there are lingering tugs and pains in me butt.

One tip - About two weeks ago, feeling sore after a session with the lawn, I popped one of my diclofenac anti-inflammatories that I had been using before surgery. Just one long-release pill. Wow! It just took away the soreness, and I felt great. I asked my doctor and he said it would be fine to do this on occasion, understanding that by the six-month point pain relief should not be necessary. So, if for some reason like me you have been going cold turkey on meds but you're feeling sore, try an Aleve or something like that. You might be surprised at the improvement.

I guess the only other thing to report is my blimping up by a few pounds. The scale provides the undeniable evidence of the net change (as do my riding jerseys) but I don't feel like I changed my eating habits. But about two weeks post surgery, with my weight having been stable, suddenly I just started the enblimpification. It's probably some depressingly simple thermodynamics that are the explanation (one extra cookie per day....), but the explanation I prefer is that the surgery has caused me to become photosynthetic, such that the spring weather has caused me to leaf out. Right. So now it's time for discipline and ramping up the riding miles.

Proof of two-hip status

Here's what things are looking like in x-ray:

More metal for the metal detectors. But still not quite a Terminator.

Where hip #2 is at.

Having two surgeries for one hip, along with the associated ups and downs, has been draining. It knocked hell out of my master plan for dealing with the work I do at the university. My entire psychology is different: whereas for my left hip, everything was great, improving, progress, this time I've ended up more negative and really cautious and worried and tentative (hence the long delay in posting anything about this surgery). 

At this point, I think I've turned the corner, and within the noise, I'm at the point where many patients would normally be. Whether by chance or due to the extra trauma, I've been experiencing a syndrome that many but not all hip patients face (whether they are conventional or Birmingham); it's the get-up-and-go problem, where you experience sharp groin pain when you stand and try and take your first step; this clears up within a moment or two, but is an annoyance in terms of mobility. I also experience more of this pain after therapy, and I am way behind on the ability to do straight leg raises: it's still hard to get the leg started at all, let alone without pain, though once I start doing the raises, it's no problem to keep doing them or even restart the exercise. But, I am just about walking pretty well without a cane and can do a mile or more with really no pain or fatigue. I'm spinning up my speeds on the bike trainer towards 17 mph, and I've gone as long as 50 minutes. 

Here's a summary of the events and sequence since surgery.

Day 1: Initial right-hip resurfacing surgery on 23 February.

Day 4: back home

Days 7-9: lots of discomfort, sense that something is wrong with joint

Day 12: Visit surgeon; get news that another surgery is needed to replace slipped cup

Day 13 (Day 1): Second surgery, 7 March. New cup with screws inserted.

Day 22 (Day 10): Hold graduate seminar home; using crutches to get around

Day 25 (Day 13): staples out, no infection, implant looks good

Day 27 (Day 15): Use cane for some walking, mix with crutches

Day 29 (Day 17): Back to work full time, lots of stair climbing descending

Day 31 (Day (19): First outpatient therapy

Day 34 (Day 22): First ride on indoor trainer: ~20 minutes, 5 miles (15.1 mph)

Day 48 (Day 36): Indoor trainer, 12 miles, 45 minutes, 16 mph

Day 50 (Day 38): Walking longer distances, basically not needing cane; still need cane a bit after therapy or after sitting for longer periods. Can sleep in any position without any real discomfort. Stretching at therapy starting to feel good rather than painful.

What's the deal with two surgeries in succession?

You might wonder what the outcome was to have two surgeries in such quick succession. Well, remembering the fundamental equation, that hip surgery = ass surgery, it is an insult to your ass, because the incision is re-used, and partly healed muscle and tissue is cut... Ouch. Dr. Ferrante closed this new incision with staples, rather than sutures and steri-strips (which he had used for the initial one).

The biggest concern is infection, with rates apparently reaching 10%, because of the greater difficulty of sterilizing the area plus the plain reality of re-exposing traumatized tissue to the environment. I did have a bit more tenderness, and a day or two extra of mild evening temperatures, but so far it looks like I'm ok. 

Other than that, the two surgeries have left me in a slightly curious hybrid state, as there was some healing from the first surgery that I retained and that wasn't reset by the second operation. So for that reason and because each hip and each surgery can be different anyway, it's a little hard to index my progress this time against progress after the surgery I had two years ago on my left hip. All in all, the net is that I'm a little more sore and weak this time, probably reflecting the additional trauma. 

Surgery 2b: groundhog day

The second surgery got off to a wobbly start in that I was told to report too early, to the wrong place, in a hospital that does not do or handle surgeries like this on the weekend. But we found a helpful person who connected us with people who were in fact looking for me. I was back in the same room that I had just left 10 days before ( it is not good when the staff remembers you!).

The surgery was short and sweet (I had a general this time, no stinking spinal (see earlier post)). The original cup was hand-loose, and although some extra cutting was needed to insure that the replacement with screws went in for sure, things went well and I was out in about 40 minutes. I woke up feeling great, and relieved that I was back in one piece with the Birmingham hip intact. I was able to head home after two days, given that this surgery was not quite as major.

We never really had an explanation for how the cup could have popped out so quickly. There was no recorded fall or incident that I had. True, my leg was numb for too long after surgery, but I didn't try walking on it or anything. Dr. Ferrante said that is went in well and firm. ALl I can figure is that the press fit was just barely ok, and it popped out under a fairly minor nudge in normal use. There's no point in blame for anyone because there is no evidence of anything particular happening, and the repair worked out. 

But... if you feel lots of sudden shifts and motion in the days post surgery, don't wait: see you surgeon. I would have saved myself a bunch of wasted recovery days if I had reported the systems and asked for an examination and x-ray.

Things go south

Once I got home, I felt like I was improving for a few days but then this stopped. My hip felt sore, and the shifting or offset thing was happening more often. Getting onto a toilet seat was horrible, just the worst, because as my femur hit the seat, I'd feel this terrible sudden motion. Not really painful, but REALLY REALLY CREEPY. 

I as scheduled to see my doctor for a followup on Friday March 6, about 12 days after surgery. By the Wednesday before that I was about to call for an early visit, but then I just thought I'd give it two more days. 

The day of the appointment, the discomfort was so great that I couldn't sit in the front, mildy shaped seats of our Prius -- I had to use the bench seats in the back. We got to the doctor's office, and about 10 minutes after getting X-rayed Dr. Ferrante came in to the examining room, and to his credit, did not beat around the bush to tell me that the cup had slipped and I would need another surgery.

This was bad news, but frankly, given how I felt, I knew something was up, and bummer that more surgery was, anything to fix the creepy motions and clunks and growing pain were fine with me. Dr. Ferrante apologized for the 10 days of lost recuperation, but said that most likely he could get me back on track fairly quickly, using a dysplasia cup that could be help in place with screws (nothing would have to be done with the femoral component, which was fine). His one concern was that there might have been some acetabular fracture or issue that had caused the cup to loosen, in which case I would need revision to a conventional hip and work to stabilize the acetabulum. But he considered this unlikely.

Chris actually asked if I had breakfast -- i.e., he was willing to operate that day! I just wasn't ready for that, so I choose to go in the next morning, a Saturday, to get the cup replaced.

Long story short: a different experience this time.

Ok, a bit of a gap there. Things turned out very differently for me this time, and I've held off from recording events until I had confidence in the outcome (translation: superstitiously, I didn't want to jinx my recovery). As you might suspect, things didn't turn out so well this time at least at first.

Lots of details that I reported about my first surgery, for the run-up and hospital stay, still apply, so I will omit those. I'll focus on what was new... and different.

My surgery on 23 February went well. I made the dumb mistake of choosing a spinal block at the last minute and it was a miserable experience. For me, never again. But if you like writhing like a pithed frog, I recommend it (and keep reading).

My first trauma was that the block did not wear off in anything like the 12-18 hours I was assured was normal. By bedtime of Day One in the hospital (12 hours after surgery), there was no feeling below my knee. Nothing at all. All night long, as the anti-clotting foot-squeezers alternated their caress, it was like "these little piggies have feeling".... "and these little piggies have none." So, no, I did not sleep, at all. By 6 am, still nothing. After 8 am and breakfast, nothing. The anesthesiologist came by, and when he heard, he said "Really!?!? That's not good! We'll get a neurologist in later." Great. Damaged nerve. Severed nerve? Have I traded a sore hip for paralysis?

Fortunately, Chris Ferrante, my surgeon, was comforting and told me to wait just a bit more before we took action. Son of gun, 15 minutes after he left, and about 26 hours after surgery, my little toe wiggled! I was healed! Within an hour, my leg was back. Still, that did not make for gentle first day. 

Everything proceeded fairly smoothly after that, but I noticed increasingly that there was an odd clunk or shifting feeling in my operated leg. My doctors thought this was just soft tissue moving, based on my description. I went home on schedule, on the Thursday following the Monday surgery.

Tomorrow, new hip #2

As I noted in my last posting to this too-much-information blog, me hip, she be aching a lot. Whether due to lack of meds or just a final breakdown, it's timely as it makes the upcoming surgery feels more like a chance for relief, not something quasi-elective I've chosen to drag myself through.

I've been commenting to people how fortunate it is to live in a time where there are remedies like this. Maybe someday we'll look back at this barbaric procedure involving cutting and grinding and sawing and gluing and implanting, instead of some bioengineered in-situ repair. But not so long ago in human history, and for much of history, if you were in your 50's with rotten hips, you were an invalid and that would've been that. And of course, for many people in the world, that's still likely to be true. So all in all, I'll take the good fortune to be able to have this repair.

If I was headed down the ski jump during my post a few days ago, at this point I am close to the lip of the jump. The best and only forward is to go through with this. I'll report on Round Two when  get back home from the hospital...

Rumbling down the ski jump again

Five days until surgery. Things feel less organized this time, maybe because I'm paying less attention, or doing it while busy, or just making the been-there, done-that mistake. In any case, I've managed to get all the required pre-operative tests, donate blood to myself, and in general cue up all the needed schedule changes and such.

Because the old clunker has reached its end and because in the run-up to surgery I'm off anti-inflammatory medication, this hip really hurts. Much as I am not looking forward to the whole hospital visit and the recovery circus, I'm ready to axe this pain.

Soon I'll be in the more rarified and elite two-Birmingham club. For the first surgery, I was relieved to have discovered a concrete cause for my aches, and I was excited about the high-tech repair, though I was a little overwhelmed by issues of mortality and aging and decrepitude. In contrast, this time, knowing that this second surgery was inevitable, knowing all the steps and procedures involved, and knowing that things can work out well, the threat level seems set lower, more a level meh.

Middle-Aged Hip Returns: The Sequel of Symmetry

Ayuh, things are going real well with the resurfaced hip, but now it's mate has packed it in. Over the holidays, my right hip started aching a lot. I spent lots of time standing during poster sessions at the American Geophysical Union meeting, and it really was a chore. All the old symptoms were back -- groin pain, sore lower back, pains running down my leg. The anti-inflammatory I'd been taking (diclofenac) wasn't really making any difference any more. After a few weeks of this getting worse, to the point of not wanting to ride my trainer, or even walk around much, I booted up the whole dance once again: referral from primary doctor, and then the visit to my surgeon, Dr. Ferrante in Easton PA. The result of that visit: February 23rd, I'm having my right hip resurfaced.

I can't say that the whole process is something I remember fondly, but if the outcome is anything like I've had with the left hip, this will be well worth it. I'm hoping for a pretty active summer, hence the decision to sneak in this surgery spanning our spring break (I'm teaching a grad seminar-- if I have to, I'll just drag the class out to my house and soldier on from there). 

I'll report succinctly on what round two was like.

So far, so real good (left hip)

A large gap in posting to this blog, but no news is good news. I had a great year riding my bike: I got in about 4200 miles, and in October 2008 I rode the Seagull Century, completing the ride at a crisp pace (for me) of about 19.5 mph. That's about as fast as I managed the ride about six years ago, and the ride include some real fast paceline intervals and some pretty frequent and rapid accelerations. I figure that at age 52 with a resurfaced hip, I'm doing pretty well.

I did some hiking over the summer outside of Tucson and also in Pennsylvania, without any issues. My visit with my surgeon in August, for the one-year checkup, was good: everything looks solid and in good nick.

Sometimes I do still get a small twinge in the resurfaced joint; it feels like I'm pulling scar tissue. And sometimes (but less often) I'll feel a small clunk, like when slumping in a chair and then dragging my heel back (I guess that pulls apart the joint just a a little). But really, I can't say that I notice the new hip at all anymore (but see next entry....).