Where Is the Incision for a Hip Replacement?

The incision for a hip replacement depends on the surgical approach your surgeon uses, and three main options account for the vast majority of procedures worldwide: the posterior approach (an incision on the back of the hip), the direct anterior approach (an incision at the front of the hip or groin crease), and the lateral approach (an incision on the outer side of the hip). Each approach places the cut in a different location, goes through different layers of muscle and tissue, and comes with its own trade-offs for recovery, scar appearance, and joint stability. Understanding where the incision goes and why can help you make sense of your surgeon’s recommendation and know what to expect on the other side of the operating table.

The Posterior Approach

The posterior approach is the most commonly used worldwide and has been for decades. Your incision runs along the back and side of your hip, roughly centered on the bony bump you can feel on the outside of your upper thigh (the greater trochanter). In a typical procedure, the cut extends about 5 centimeters above the top of the greater trochanter along the line toward the back of your pelvis, and about 4 centimeters downward, for a total length in the neighborhood of 9 to 12 centimeters depending on your body size and the surgeon’s technique.¹ You lie on your side during surgery with the operated hip facing up.

After the skin is opened, the surgeon cuts through the thick band of tissue on the outside of the thigh and then detaches a group of small muscles called the short external rotators, including the piriformis and the gemelli, to get to the joint capsule underneath. The capsule itself is then opened with a T-shaped or L-shaped cut to expose the hip joint.² Those detached muscles are typically sewn back together at the end of surgery, and whether the surgeon repairs them carefully matters quite a bit. A multicenter study found that preserving the piriformis muscle during the posterolateral approach was linked to zero early dislocations compared to a nearly 3% rate when the muscle was cut in the standard fashion.³

The posterior approach gives surgeons excellent visibility of the hip socket and femur, which is one reason it remains so popular. It also works well for a wide range of patient body types and is the approach many surgeons learned first during training. The scar sits where clothing and even most swimwear covers it, which many patients appreciate.

The Direct Anterior Approach

The direct anterior approach places the incision at the front of your hip, typically starting a couple of finger-widths below and to the outside of a point on your pelvis called the anterior superior iliac spine, which is the bony ridge you can feel at the front of your hip bone. The cut runs roughly downward and slightly outward, and in most cases measures around 8 to 12 centimeters. You lie on your back during surgery rather than on your side.

What makes this approach distinctive is the path through tissue. Instead of cutting through muscles, the surgeon works between two natural gaps in the muscle layers at the front of the hip. This “intermuscular, internervous” plane means the muscles themselves are spread apart rather than detached from bone.⁴ Because no muscles are cut, early recovery can be faster. One study using smartphone accelerometers found that patients who had the anterior approach walked significantly faster and took longer steps at one month compared to those who had the posterior approach, though by four months the two groups looked the same.⁵

The anterior approach has surged in popularity over the past 15 years, partly driven by patient interest in faster early recovery. Surgeons performing it often use intraoperative fluoroscopy (a real-time X-ray machine) to check implant positioning while you are still on the table. That sounds reassuring, but the imaging has limitations. One study found that in nearly all hips checked with fluoroscopy, the cup was placed with unrecognized excess anteversion and inclination because the pelvis was in an extended position during imaging.⁶ Fluoroscopy-assisted computer navigation systems have since been developed to improve accuracy.⁷

The Lateral Approach

The lateral, or direct lateral, approach puts the incision squarely on the outer side of your hip, centered over the greater trochanter. The cut typically runs vertically or slightly angled, and the surgeon splits or partially detaches part of the gluteus medius muscle, which is the main muscle responsible for keeping your pelvis level when you stand on one leg. This gives good access to the hip socket but comes at a cost: splitting even a small amount of the gluteus medius can weaken hip abductor strength, and one study found that impairment persisted two and a half years after surgery.⁸ A weakened gluteus medius can produce a limp, sometimes called a Trendelenburg gait, where the pelvis drops on the opposite side during walking.

Because of this trade-off, the lateral approach has become somewhat less common for primary hip replacements compared to the posterior and anterior approaches, though it remains widely used, especially in revision surgeries and certain fracture cases where the surgeon needs broad access.

The Direct Superior Approach

A newer option that has gained traction is the direct superior approach. Here, the incision is made at about a 60-degree oblique angle, starting from the back-upper corner of the greater trochanter and running upward and slightly forward for about 8 to 10 centimeters. The surgeon splits the gluteus maximus muscle bluntly, meaning along its natural fiber direction rather than cutting across it, and the iliotibial band on the side of the thigh is completely spared.⁹ This preserves the structures that contribute most to hip stability while still providing good surgical access.

Some surgeons have transitioned to this approach from the posterior approach and reported improved early outcomes without a significant learning curve.² The scar sits in a slightly different position than the standard posterior scar, running more diagonally across the upper buttock region.

Dislocation Risk and Why the Incision Location Matters

Where the incision goes is not just a cosmetic question. The path the surgeon takes to reach the hip joint directly affects how stable the new joint is afterward. Dislocation, where the ball slips out of the socket, is one of the most feared early complications of hip replacement. A large meta-analysis pooling data from roughly 125 studies and about five million hip replacements found that the posterior approach carried roughly double the dislocation risk compared to the anterolateral approach, and about 60% higher risk compared to the lateral approach. The direct anterior approach, by contrast, was associated with about 43% lower dislocation risk than the posterior approach.¹⁰

That sounds like a strong argument for the anterior approach, but context matters. When surgeons using the posterior approach repaired the soft tissues they had detached, particularly the external rotators and the capsule, the dislocation risk dropped dramatically. The same meta-analysis found that posterior-approach procedures with repair had only about a quarter of the dislocation risk compared to those without repair.¹⁰ In other words, a well-executed posterior approach with careful repair closes much of the stability gap. Individual studies have also shown zero dislocations in anterior-approach groups over follow-up periods of one to five years, compared to dislocation rates of 1 to 4 percent in posterior-approach groups.¹¹¹²

The Bikini Incision and Scar Cosmetics

If you are having an anterior-approach hip replacement and care about scar appearance, it is worth asking your surgeon about the “bikini incision.” The standard anterior incision runs more or less vertically down the front of your hip. The bikini incision follows the natural skin crease at the groin, running obliquely so it can be hidden below a bikini line or underwear waistband. The surgical destination is the same hip joint, but the scar lands in a less visible spot.

A meta-analysis of eight studies covering over 2,000 hips found that the bikini incision produced significantly better scar cosmesis scores without adding any extra operating time.¹³ Patient satisfaction with the scar was also higher.¹⁴ However, the bikini incision does come with a trade-off: high-quality randomized trials within the meta-analysis showed roughly double the risk of injury to the lateral femoral cutaneous nerve, which supplies sensation to the outer thigh.¹³ This nerve injury typically causes numbness or tingling on the front-outer part of the thigh. It is usually not painful, and symptoms tend to improve with time, but it is something to weigh if you are deciding between the two incision options.

Nerve Injury and Where the Cut Goes

Every surgical approach runs close to at least one major nerve, and the incision’s location determines which nerves are most at risk. The posterior approach has long been associated with potential injury to the sciatic nerve, which runs behind the hip joint. But this reputation may be somewhat overblown. A study that compared nerve function using electrophysiological testing before and after surgery found that all nerve injuries detected actually occurred in patients who had the lateral approach, not the posterior approach, even though the patients in neither group had symptoms they noticed.¹⁵ The study was small, so it does not prove the posterior approach is nerve-safe, but it illustrates that clinical assessment alone underestimates nerve injury rates and that the lateral approach carries its own risks to the obturator and femoral nerves.

The anterior approach, meanwhile, puts the lateral femoral cutaneous nerve at risk because it runs through the surgical corridor at the front of the hip. This nerve is purely sensory, so damage does not affect muscle strength, but numbness or burning on the outer thigh is the most commonly reported nerve issue with this approach. The bikini incision variant increases the risk somewhat, as described above.

Early Recovery Differences Between Approaches

Patients often ask whether one incision site leads to a noticeably faster recovery. The honest answer is that the early weeks differ, but the long-term outcomes are remarkably similar across approaches. The anterior approach tends to produce less pain in the first few days to the first week, with one systematic review and meta-analysis reporting significantly lower pain scores and better functional hip scores at six weeks compared to the posterior approach.⁴ The gait advantage at one month fades by four months.⁵

By the six-month to one-year mark, most studies show no meaningful difference in walking ability, hip scores, or pain between the anterior and posterior approaches. One gait analysis study tracking patients out to a year found nearly identical improvements in hip range of motion and walking mechanics, with the only persistent difference being slightly better internal and external rotation in the anterior group, likely because the external rotator muscles are not detached in that approach.¹⁶

What this means practically is that if a faster return to driving, work, or normal daily activities in the first month or two matters to you, the anterior approach may have a slight edge. But if your surgeon is most experienced and comfortable with the posterior approach, the long-term result is not likely to be compromised. Surgeon experience with a given approach consistently ranks as one of the most important factors affecting outcomes.

What Determines Which Approach Your Surgeon Recommends

Several factors shape the choice of approach. Training and experience are paramount: a surgeon who has done thousands of posterior-approach replacements with excellent outcomes may not serve you better by switching to an anterior approach they have less experience with. Previous surgeries on the same hip also matter, because old incisions and scar tissue may dictate the approach that allows the safest access. Your body habitus plays a role too. The anterior approach can be more technically demanding in very muscular or obese patients because the muscles at the front of the hip are harder to retract, while the posterior approach accommodates a wider range of body types.

The specific pathology being treated is another consideration. For a straightforward primary hip replacement due to osteoarthritis, all approaches are viable. For complex revision surgery where an implant needs to be removed and replaced, the posterior or lateral approach may provide better access. For certain hip fractures, the lateral approach may be preferred. Ask your surgeon which approach they use most often and what their complication rates look like, as this is generally more predictive of your outcome than the theoretical advantages of any particular approach.

Wound Care and What Your Scar Looks Like Afterward

Regardless of the incision location, the wound is closed in layers. Deeper layers are sutured with dissolving stitches, while the skin may be closed with staples, stitches, or adhesive strips depending on surgeon preference. A dressing is applied, and some surgeons use negative-pressure wound therapy (a small vacuum device over the incision) in patients at higher risk for wound complications, such as those with obesity. One study found that negative-pressure therapy in high-risk patients reduced readmission and reoperation rates compared to standard dressings, though the overall infection rate difference did not reach statistical significance.¹⁷

Scar length varies, but most incisions for primary hip replacement fall between 8 and 15 centimeters. Scars from the posterior and lateral approaches sit on the side or back of the hip, where they are typically covered by clothing. The anterior scar runs down the front of the thigh or, with the bikini variant, in the groin crease. Over time, all of these scars tend to fade significantly, though scar appearance depends heavily on individual healing, skin type, and whether any wound complications arise.

Minimally Invasive Versus Standard Incisions

You may hear the term “minimally invasive” used in connection with hip replacement. This generally refers to performing the surgery through a shorter incision and with less muscle disruption, rather than to a fundamentally different operation. The anterior approach is sometimes marketed as inherently minimally invasive because it works between muscles rather than cutting them, but a “mini” version of the posterior or lateral approach can also be performed through a smaller skin incision with careful muscle handling.

The evidence suggests that the real benefit of minimally invasive techniques comes from reduced soft-tissue damage rather than skin incision length. A shorter skin cut does not automatically mean less trauma to the underlying muscles and tendons. Conversely, a slightly longer incision that allows the surgeon to see what they are doing and place the implant precisely is better than a short incision that compromises visibility. If a surgeon tells you they use a “minimally invasive” approach, the useful follow-up questions are which muscles are cut or split, how the implant position is verified during surgery, and what the surgeon’s complication rate has been with that technique.

When the Approach Changes Postoperative Restrictions

The incision location can also influence what you are told not to do after surgery. Patients who have the posterior approach are traditionally given “hip precautions,” a set of movement restrictions designed to prevent dislocation: do not bend the hip past 90 degrees, do not cross your legs, do not twist inward. These restrictions typically last six to twelve weeks and can make everyday tasks like putting on shoes or getting in and out of a car more challenging.

Patients who have the anterior approach are often given fewer restrictions, or none at all, because the muscles and capsule at the back of the hip remain intact and help keep the ball in the socket. One study found lower dislocation rates in the anterior group despite fewer movement restrictions being imposed.¹¹ For many patients, the freedom to bend and move more naturally in those first weeks is one of the most tangible differences they experience between the two approaches, even if the long-term functional outcome ends up being similar.