Hip Pain When Running - Is it Soft tissue/training issues, or is it Prosthesis Loosening?

The answer to this question determines my allowable activity level. It's hugely important. I've got to get a believable answer. So, I'm going to organize the theories and the evidence...

The Pain Closest to Hip Joint: Anterior to femoral head. If 12 o'clock is perfectly anterior, and 6 o'clock is the middle of my left glutes on my backside, and 3 o'clock is the medial direction, this pain is at 12 or maybe 12:30 o'clock. It is not sharp, and not focal, but more diffuse. I've seen swelling here after half marathon races and it feels warmer to the touch than the normal right hip. Usually swelling is minimal or undetectable. The pain comes on and once it's there, it doesn't go away until I stop running. Resting momentarily will often help some, but it'll come back a half mile later or less. Ibuprofen is effective at knocking it down. So is an ice pack. Very early in my return to running, 1 year post surgery, I had a race and 3am the next morning this pain woke me up and it was quite severe. Xrays were normal, but it hurt for days. This gradually went away, and I've had some long runs with no pain onset. But other times it'll hurt before the end of the first mile. In ~'07, '08 I had often a feel of "snapping hip syndrome" around the femoral head (never over the trochanter). With stretching and strengthening, this seemed to go away. However, now in late '12 and early '13 it's returned, not nearly as severe. It may correlate in time with these times of this particular pain. The "snapping hip" moments themselves are not painful, just a bit annoying. As of late April, I can't claim the snapping hip syndrome is really noticable, and it appears to have receeded quite a bit in the past couple of months. However, my tolerance for running continues to decline. I can do a couple of miles if I'm lucky. Maybe 1 mile if it's uphill, as of Apr 19 2013 when I tried to run up to UCSC for a seminar, from Harvey West Park.

Theory: Pain is due to the psoas tendon rubbing over the metal cup, perhaps the cup edge protrudes beyond the acetabular bone edge. Psoas tendinitis and bursitis go together

Image #1: This bursa describes exactly where and how large my anterior hip pain is

Image #2: The Iliacus muscle also goes right under the psoas tendon and right over the femoral head. Could it be involved?

Image #3: My Feb 14, 2013 AP view

Image #4: May 10, 2011 AP view, but I was standing and weight bearing, so my hip is not as open to the camera as in '13 when lying flat.

Image #5: Apr 2, 2009. This is just after my very painful "Skippys Triathlon" race; my second triathlon after surgery. Not much running mileage yet on this metal hip.

 

Evidence in Favor:
-- the location is correct, according to image #1
-- the pain goes away after the inflammation stops, within an hour or a few hours after stopping my run. Sometimes residual pain lasts for a day or two, enough to convince me to not run until it goes away.
-- Stretching the psoas doesn't feel good, in contrast to many other areas of the body where stretches do feel just fine. Instead, it hurts, as if I might be pulling on fresh scar tissue(?)

Evidence Against:
-- My psoas does not appear to be particularly "tight", according to physical therapist Jeff Moreno. It stretches to normal length when lying on table, letting leg fall over edge, and bending right knee to chest. However, I note that it is not nearly as loose as my other (right side) psoas when sitting and crossing over ankle on top of opposite knee, a common way some people sit.
-- stretching my right side (normal hip) psoas doesn't feel much better. Similar level of range of motion as left.
-- when my hip hurts during running, I often will stop and do a one-legged stand pulling up on left ankle to strech the psoas and hip flexors. Doing so is NOT noticably painful. There's some pain in the hip, but it is not made worse by these stretches.

Theory: Loosening of the Magnum cup on the lateral side.

Evidence in Favor of cup loosening:
-- Gap on Xray at extreme lateral cup edge, pointed out by Dr. Christoffersen
-- Is the semi-circular region about 1 cm thick which defines the bone above the cup, normal? It's barely visible in the '11 images, but much more obvious in the Feb '13 images. Progression of some sort of bone metabolism abnormality? This region is the area of maximum compressive forces during running. It's possible I could have both issues; early loosening, and also psoas tendinitis, so it may not be either/or.

Evidence Against cup loosening:
-- my pain goes away quickly after running. Within a day and ofen much less. Certainly as soon as I take an Ibuprofen (and wait ~45 min), although that is usually not what I do, I just wait. Bone pain should be more constant. Bone damage and pain does not heal in minutres or hours or even a few days, but many weeks or a couple of months.
-- There is no progression according to Dr. Christoffersen, comparing to my '09 X-rays. This would not be expected, as my running mileage has certainly increased; 450 miles in '10, 540 miles in '11, and 605 miles in '12.
-- Bone scan taken Mar 28, '13, has this radiology report . Bottom line, "loosening is unlikely". While there's some additional bone metabolism on the left side vs my right hip, this would seem more likely to be due to ongoing bone remodelling and bone building due to the eustress of running, in a healthy sense.
-- After this report, I conducted an experiment: I did another UCSC run to the IGPP Friday seminar. If my pain was bone pain, the long layoff from running would make my bone more healed, and I'd expect to be able to run longer before any pain set in. On the other hand, if it was muscle/tendon, then the layoff would weaken these and my characteristic pain would set in sooner. Outcome: I got about 2, maybe 2.3 miles, into Pogonip, before my pain started, and it got worse the rest of the way, and homeward as well, although downhill wasn't quite so bad (which again indicated muscle/tendon, not bone). What about hip flexor strength? Today, after the 9 mile run yesterday and the 60 mile bike ride with 4700 ft climbing, my hip flexors are a little sore, and I cannot do even one single leg raise (which seems pathetic, in fact. this may indeed be important).
-- rest should help any bone healing and lengthen amount of time before pain sets in. But that's not what I'm experiencing this year. On Apr 19 '13 I tried to run up to UCSC (granted, I did a 3 mile run 2 days prior, mostly on pavement, some on hard beach sand), I was only able to get up the Pogonip trail 1 mile before having to walk, slow jog the remains to get to the IGPP seminar. An hour later, coming back down was a mixture of walking and jogging. Did 2 ibuprofens before the whole thing was done, and pain was gone by the next morning.

Theory: It's weak hip flexors, which are exhausted and cramping.

Evidence in favor:
-- I feel more pain on uphill running than downhill, yet downhill is when there is more impact on my bone, and uphill is when I'm most engaging the psoas and hip flexors.
-- really same as for psoas; soft tissue recovers quickly, bone takes months. Now, I'm trying to remember how my bone pain felt when I broke my toe last year.Did the pain at least significantly go down when I didn't run? It did. However, it was always there to some extent. My hip pain is (usually) entirely gone if I'm not running.

Evidence against:
-- that gap on the X-rays perhaps?

Test:
-- why not both legs, why just the left? So use ankle weight and to test-to-failure of leg raises for each leg. I just don't get a clear signal when doing straight-legged leg raises.

 

PT ideas