Minimally invasive hip replacement means a small incision for most patients. However, the real benefit comes from how the muscle is handled, not from how short the scar is. A smaller incision on its own does not make you recover faster.
What changes your first two weeks is how much invasive the surgery was, how hard it was pulled on, how long the operation took and how much blood was lost. This page covers what I spare, who needs a longer incision, and what the scar will look like.
Minimally invasive is about the tissue, not the tape measure
Patients ask how long the scar will be, and I understand why, because it is the only part of the operation they can see. It is the wrong measure. A four inch incision with two hours of hard retraction underneath it damages more tissue than a five inch incision handled gently.
I tell patients my incision is as small as possible and as large as needed, and I will not compromise the outcome for the length of the scar. That sentence is the whole of my position.
What I am trying to spare
Muscle that is cut across, heals with scar. So the large muscle of the buttock is split along its fibers, and the short muscles at the back are taken off the bone with a cuff and sewn back to bone at the end rather than left alone.
Tissue crushed by retractors. This is the invisible half. A retractor sitting under tension in one spot for ninety minutes does damage that never appears in a photograph of a scar. I place retractors under direct vision, I move them, and I use instruments designed to work through a small window so that I am not levering against soft tissue to see. Before placing retractors, I make sure the nerve is far away from it and protected.
Time. A shorter operation means less exposure, less bleeding and lower infection risk. Almost all of the “time saving” in my cases comes from preparation rather than speed.
The preparation that shortens the operation
I plan several days ahead off your films. The size of the shell, the size of the stem and the expected neck length are decided then, not on the day. On the morning of surgery I confirm everything is in the room before I come to meet you. Then, and only then, I come and find you.
| When | What is already settled |
|---|---|
| Several days before surgery | The size of the shell, the size of the stem and the expected neck length are decided off your films. |
| Before I come to meet you on the day | The implants are open and assembled where they can be.
The reamer size I expect to need is on the table, because in most hips that is a particular size and I know it before I start. The suture is already loaded on the needle. The trays are laid out from a preference card I wrote myself. |
None of that appears anywhere and it is most of the reason a hip replacement in my hands takes about an hour. Occasionally there is a hiccup at the back table, a reamer jamming or a saw battery failing, and those are extremely rare precisely because everything is checked first.
The instruments make the small incision possible
You cannot simply perform a traditional hip replacement through a smaller hole. The instruments have to be designed for it: offset handles that keep the surgeon’s hand out of the line of sight, broach handles angled away, low-profile retractors, reamers on flexible shafts.
That is the honest reason minimally invasive hip replacement was not routine decades ago. It was not that surgeons preferred long incisions. The tools to work through a short one did not exist. The instruments and the techniques slowly came into existence.
Who gets a “longer” incision
In the overwhelming majority of cases, I know exactly the length of the incision. However, if I feel the need to increase the length do so immediately if the operation asks me to. I do not compromise the long-term outcome under any circumstances. Typically the following will have a longer incision than the typical hip replacement –
- A very heavy or very muscular patient.
- Significant deformity from childhood hip disease.
- A hip that has been operated on before.
- A femur containing a plate or a rod.
- A rare instance where I cannot get to a bleeder at the age of the incision.
- I tell patients this beforehand rather than afterwards. Nobody has ever come back at a year unhappy about an inch of scar.
What actually changes for you in the first two weeks
I want to be careful not to overclaim here, because a great deal of what is written about minimally invasive surgery overclaims.
What I see in my own patients: they stand the same day, most are off the walker within three to six weeks, they need less pain medication in the first week than patients used to, and most go home the same day or the next.
What I do not tell people is that a smaller incision by itself produces a faster recovery. It does not. A patient who was strong and mobile beforehand recovers faster than one who was not, and that difference is larger than anything I do with a knife.
By three months, and certainly by a year, I cannot tell from the way somebody walks how long their incision was.
Questions I get about the scar
Where will the scar be?
Over the back and side of the hip if I go from behind, at the front near the crease if I go from the front.
What will the scar look like?
At six months a pink line, flat and still firm to the touch. At two years usually a pale line most patients have to look for. Some patients have a propensity to develop keloid, and that depends on whether they have had a keloid formation in the past. Of course, how will the scar gels in with the skin color depends on the skin color.
Will there be a numb patch beside it?
It is seen commonly after Anterior Hip replacement especially if examined carefully. Small skin nerves are unavoidably divided by any incision and the patch usually shrinks over a year. This thigh numbness is caused by a specific nerve at the front of the hip.
Can I put anything on the scar?
Once the wound is completely closed and dry, you can apply anything you want and I do not know if one sort of lotion works better than the other.
What the result looks like, whatever the incision length
Films from my own patients. Nothing on an X-ray tells you how long the incision was, which is rather the point of this page.
Front view of the pelvis after a left total hip replacement, with a screw holding the socket. The right hip is the patient’s own. Written up separately as Left Total Hip Replacement in a 77-year-old female with Hip Arthritis. My own imaging, anonymized before publication with the embedded data removed.
Front view of the pelvis after a right total hip replacement, with a screw holding the socket. The left hip is the patient’s own, and previous spinal surgery is visible at the top of the film. Written up separately as Management of Right Hip Arthritis with Robotic Total Hip Replacement. My own imaging, anonymized before publication with the embedded data removed.
Frog-leg side view of the right hip after a total hip replacement, showing the stem, the ball and the socket. Written up separately as Right Total Hip Replacement in a 75-year-old female. My own imaging, anonymized before publication with the embedded data removed.
Frog-leg side view of the right hip after a total hip replacement. Written up separately as Bilateral Total Hip Replacement in a 65-year-old female. My own imaging, anonymized before publication with the embedded data removed.
Frog-leg side view of the left hip after a total hip replacement, with a screw holding the socket. Written up separately as Left Hip Total Replacement in a 54-year-old female with Hip Arthritis. My own imaging, anonymized before publication with the embedded data removed.
Commercial interests in minimally invasive claims
No manufacturer of minimally invasive instrumentation pays me anything, and no implant company has any financial relationship with me. Claims about smaller operations are marketed hard, so the disclosure matters on this page.
This page describes my own practice and judgement. It is not medical advice for your situation. Please see a physician about your own condition.
