Could SPAIRE hip replacement suit your hip?

Online comparisons of SPAIRE hip replacement and “bikini incision” hip surgery can make it sound as if one option must be the right answer for every painful hip joint. In reality, SPAIRE is a specific variation of a posterior hip approach, and the key first step is working out whether a muscle-sparing posterior approach fits the shape of the hip, the reason for surgery, and the goals for early movement. Clinic-specific detail is kept brief here, so the focus stays on what suitability usually means in practical terms.

SPAIRE (Save Piriformis And Internus, Repair Externus) is performed through the back of the hip and is designed to preserve selected small rotator tendons rather than routinely detaching and reattaching them, with the aim of improving early stability and mobilisation after a full hip replacement where appropriate. It sits alongside other commonly used approaches—standard posterior, direct lateral, direct anterior, and techniques such as SuperPATH—each offering different trade-offs in access, soft-tissue handling and recovery experience.

Across large reviews of total hip replacement approaches, strong head-to-head evidence has not identified a single approach that is consistently superior for all patients, and expert guidance emphasises surgeon experience with their chosen approach.

In day-to-day planning, patient suitability often comes down to factors such as:

• hip anatomy and offset (including “small anatomy” considerations)
• diagnosis and deformity (for example dysplasia or impingement)
• previous hip surgery or fracture pattern
• body habitus and rehabilitation priorities

At Lincolnshire Hip, Professor Paul Lee (trained in SPAIRE at the Exeter Hip Unit) offers SPAIRE as one option within a consultant-led pathway where clinically appropriate, alongside other hip approaches and hip-preserving options. Lincolnshire Hip is part of the MSK Doctors group and accepts patients without referral for hip assessment in Grantham and Sleaford.

What are your main hip replacement approach options?

Most total hip replacements are performed through one of three established routes around the hip joint: posterior (from the back), direct lateral (from the side), or direct anterior (from the front). These are often presented as dominant options, with broadly comparable overall safety when the approach is used well and for the right indication.

With a standard posterior approach, the incision sits behind the hip, giving direct access to the back of the joint. In many classic posterior techniques, some of the short external rotator tendons and the posterior capsule are taken down to reach the joint and then repaired at the end. That disruption-and-repair pattern is one reason posterior surgery has historically been linked with concern about posterior dislocation, even though contemporary repair techniques and implant positioning have narrowed differences in many settings.

A direct lateral approach comes in from the outer side of the hip. It commonly involves splitting (and later repairing) part of the abductor mechanism, including fibres associated with gluteus medius, to access the joint. In some comparative work, dislocation rates have not differed significantly from posterior in selected groups, but the lateral route carries a recognised trade-off: some patients can develop a temporary Trendelenburg-type limp or abductor weakness during early recovery.

The direct anterior approach reaches the hip from the front, often described as an intermuscular route that can reduce the need to detach major muscles. Recent comparative studies (including a randomised trial of a muscle-sparing direct superior technique and a cohort comparing anterior with posterolateral surgery) report patterns such as shorter incisions, less blood loss and earlier ambulation, with broadly similar complication rates and medium-term functional scores. Anterior surgery can also bring its own approach-specific issues, including nerve irritation and wound-related problems in some patients.

Alongside these three routes, newer “muscle-sparing” variations aim to limit disruption while keeping reliable access for accurate implant placement—this is where techniques such as SPAIRE hip replacement (a tendon-sparing posterior variant), direct superior approaches and SuperPATH-style methods sit within the overall map of options.

• Posterior: often prioritises familiar access and exposure; stability depends on soft-tissue handling and repair.
• Lateral: can support stable cup positioning, but may trade this for early abductor weakness/limp in some cases.
• Anterior / other muscle-sparing variants: may prioritise earlier mobilisation in some studies, with different approach-specific risks and technical demands.

Where does the SPAIRE muscle-sparing posterior approach fit in?

What SPAIRE changes in a posterior hip replacement

SPAIRE hip replacement (Save Piriformis And Internus, Repair Externus) is a muscle-sparing posterior approach that modifies how the surgeon enters the back of the hip joint. In the original description (published in 2016), the aim is to preserve the piriformis and obturator internus tendons and repair the obturator externus (rather than routinely detaching and reattaching the short external rotators in the classic way), alongside careful posterior soft-tissue repair.

Those small, deep rotator tendons at the back of the hip act like local “guy ropes” for the joint. The practical idea behind SPAIRE is that keeping more of that posterior soft-tissue envelope intact may support early stability and control, which in turn may help some people feel more confident when they first start standing and walking after surgery.

What the current evidence shows most clearly (mainly fracture surgery)

The strongest published comparative data so far largely come from hip fracture hemiarthroplasty (replacement of the femoral head). In a retrospective series reported in the British Journal of Surgery, the SPAIRE group (n=43) had 0 dislocations, compared with 2/97 (2%) after an anterolateral approach and 2/54 (3.7%) after a posterior approach; average “return to mobility” was 1.4 days with SPAIRE versus 2.0 and 2.6 days in the other groups. A wider systematic review similarly concluded that SPAIRE may offer short-term advantages (including early mobility and pain measures) but that longer-term function and patient-reported outcomes appear broadly similar between approaches.

Limits and what is still being studied in planned total hip replacement

For planned (elective) total hip replacement, SPAIRE evidence is growing but remains less definitive than the fracture literature, and further comparative research is ongoing, including the NIHR-funded HIPSTER trial evaluating tendon-sparing posterior techniques. High-volume experience reported in 2024 (including 1,026 primary total hip replacements performed with SPAIRE since February 2016) also emphasises technical limits: the approach can be more demanding in small anatomy, reduced offset, or a marked external rotation deformity, and may not be the best fit for every hip.

In Lincolnshire Hip’s consultant-led pathway, informed by Prof Paul Lee’s SPAIRE training and day-to-day practice, SPAIRE hip replacement is therefore positioned as one tool within a balanced comparison against other established approaches, with patient suitability determined by anatomy, diagnosis and operative goals rather than a one-size-fits-all label. This section summarises the published evidence in plain language, without displaying internal reference tags used during drafting.

Who is and is not a good SPAIRE candidate?

Supporting sources for the points below are listed as endnotes rather than shown as in-line drafting tags.

Patterns that often suit a tendon-sparing posterior approach

SPAIRE hip replacement is a muscle-sparing posterior approach, so it tends to be considered when preserving the small tendons at the back of the hip joint is both achievable and helpful for the surgical goal.

A brief “real clinic” contrast helps. One common scenario is a straightforward painful hip osteoarthritis case with good movement and no major deformity on an X‑ray: tendon preservation may be technically realistic, and SPAIRE can sit on the shortlist alongside standard posterior, lateral, anterior and SuperPATH-style options. A second scenario is a very stiff hip held in external rotation with reduced offset: published high-volume experience notes SPAIRE can be more demanding in small anatomy, reduced offset, or an external rotation deformity, so another approach may offer safer exposure and more reliable reconstruction.

Hip shape: dysplasia, impingement and why exposure can change

Complex anatomy can shift the balance. Developmental dysplasia (a shallower socket) can alter how the ball and socket meet and where the tight tissues sit. Femoroacetabular impingement (cam/pincer shape) can make the hip “jam” in certain positions. When the shape is altered like this, achieving accurate implant positioning and secure soft-tissue repair from a tendon-sparing posterior window may be harder—or occasionally less necessary—than using a different route.

Previous surgery or metalwork around the hip

Earlier operations (for example hip arthroscopy, osteotomy, or fracture fixation) can leave scarring or hardware that changes the safe planes around the joint. In these cases, the decision is often less about the label “SPAIRE” and more about which approach—SPAIRE, standard posterior, lateral, or anterior—gives the clearest view with the least additional soft-tissue disruption.

Whole-person factors that influence stability and rehab

Suitability is also shaped by function: severe stiffness, marked muscle wasting, balance problems, or neurological conditions can affect how stable the hip feels after surgery and how reliably the short rotators can be preserved and protected during early mobilisation.

At Lincolnshire Hip, suitability is explored through a surgeon-led assessment—history, examination and X‑rays, with MRI or other imaging when needed—so Prof Paul Lee can explain which approach he recommends for that individual hip joint, including the main trade-offs. Lincolnshire Hip is part of the MSK Doctors group and accepts patients without referral for hip assessment.

What do scars and recovery look like with SPAIRE and bikini cuts?

Scars can be a useful clue to where the surgeon went in, but they can also be a source of confusion—especially online where “SPAIRE hip replacement” and “bikini incision” are sometimes presented as if they are interchangeable.

Bikini incision vs SPAIRE: different directions into the hip joint

A bikini incision describes a skin cut used for some anterior hip replacements: an oblique line placed in a natural groin crease (the “bikini line”). By contrast, SPAIRE hip replacement describes a muscle-sparing posterior approach to the hip joint—so the skin incision is usually positioned more towards the outer-back of the hip/buttock region rather than the front-of-groin crease. These are separate ideas, and in most cases a true bikini-line scar and a true SPAIRE posterior approach do not go together because they access the hip from different directions.

What a SPAIRE scar often looks like over 12 months

Because SPAIRE is a posterior route, the scar is typically an arc/line over the side–back of the hip, rather than a crease-line scar at the front. In the first 2–6 weeks, it is common for any hip replacement scar (whatever the approach) to look raised or red and to be surrounded by bruising; by 3–12 months, many scars gradually flatten and fade, although pigment and thickness vary between individuals and skin types.

Early recovery: what tends to be felt and what the studies suggest

In tendon-sparing posterior work, the aim is to preserve key short rotator tendons; published SPAIRE hemiarthroplasty series report earlier “return to mobility” averages (for example 1.4 days in one retrospective cohort of 43 SPAIRE cases versus 2.0–2.6 days in comparator groups). Systematic-review conclusions remain cautious: SPAIRE may offer short-term advantages (mobility and some pain measures) while longer-term function and patient-reported outcomes appear broadly similar to more conventional approaches.

Even with an earlier start, most people still notice deep muscle soreness around the back/side of the hip and benefit from a structured physiotherapy plan to rebuild hip confidence, balance and strength, regardless of whether the operation was posterior, lateral or anterior.

Where Lincolnshire Hip fits

Within Lincolnshire Hip, the scar and recovery discussion sits inside a balanced comparison and patient suitability assessment led by Prof Paul Lee, rather than being driven by the label on the incision. Lincolnshire Hip is part of the MSK Doctors group and accepts patients without referral for hip assessment.

How do NHS and private options shape your hip surgery plan?

Waiting time is often the first practical factor that shapes a hip replacement plan in the UK: NHS care is usually organised through a referral and a waiting list, while private care is often scheduled to a specific date.

On the NHS, hip replacement is generally considered when hip pain and loss of function persist despite non-surgical treatments (for example physiotherapy or injections). Waiting lists can mean a significant delay before surgery takes place even when the indication is clear, which can make planning around work, caring responsibilities and flare-ups harder to control.

Private hip replacement, by contrast, can sometimes be arranged sooner (with timings varying by provider and region). When comparing like with like, the important detail is what is included (implants, hospital stay length, follow-up, and physiotherapy), not just the headline number.

Within Lincolnshire Hip, the private pathway is presented as a combined “local access + London surgery” model: assessment and planning in Grantham or Sleaford with Prof Paul Lee, surgery with an overnight stay at Weymouth Street Hospital (Harley Street, London), and then follow-up and physiotherapy back in Lincolnshire. SPAIRE hip replacement may be used within this pathway when the hip joint and patient suitability support a muscle-sparing posterior approach (rather than being treated as the default for every hip).

Choosing a surgeon or centre tends to be more meaningful than choosing a marketing label. SPAIRE-specific reporting highlights that the technique can be more demanding in certain anatomies (for example small anatomy, reduced offset, or an external rotation deformity), and that comparative evaluation in elective total hip replacement remains an active research area (including the HIPSTER trial).

Questions commonly worth asking at any consultation include:

• Which approaches are genuinely offered for that hip joint (posterior, direct lateral, direct anterior, and muscle-sparing posterior options such as SPAIRE or SuperPATH), and what trade-offs are expected in that specific case.
• What makes the hip “suitable” (or not) for a tendon-sparing posterior option—particularly if there is deformity, stiffness, prior hip surgery, or altered anatomy.
• How rehabilitation is organised after discharge (for example, structured physiotherapy locally versus ad hoc arrangements), and who coordinates follow-up at 2–6 weeks and beyond.

Across NHS and private routes, the same three decision anchors keep the comparison grounded: the timescale, what the package includes beyond the operation (especially rehab), and the surgeon’s hip-focused experience with the approach recommended for that individual hip joint. Lincolnshire Hip is part of the MSK Doctors group and accepts patients without referral for hip assessment in Sleaford and Grantham.

1. [1] 565 The SPAIRE Technique for Hip Hemiarthroplasty - an Alternative Approach to the Hip. (2023). https://doi.org/10.1093/bjs/znad258.669 https://doi.org/10.1093/bjs/znad258.669
2. [2] Rethinking Hip Surgery: A Systematic Review of Sparing Piriformis and Internus, Repairing Externus (SPAIRE) vs. Traditional Hemiarthroplasty Approaches. (2025). https://doi.org/10.7759/cureus.89115 https://doi.org/10.7759/cureus.89115
3. [3] A STANDARD OF CARE IN HIP ARTHROPLASTY: ROUTINE USE OF THE TENDON-SPARING SPAIRE TECHNIQUE WITH MAKO ROBOTIC ASSISTANCE. (2024). https://doi.org/10.1302/1358-992x.2024.16.030 https://doi.org/10.1302/1358-992x.2024.16.030
4. [4] Technical Tip: The Modified SPAIRE (Spare Piriformis and Internus, Repair Externus) Approach for Hip Arthroplasty Surgery. (2023). https://doi.org/10.36959/453/601 https://doi.org/10.36959/453/601