Hip Replacement in Pictures

1

Stage One

Surgical Approach & Exposure

Illustration showing the posterolateral skin incision line marked over the hip, with the underlying bony anatomy of the pelvis and proximal femur visible

The skin incision. The curved posterolateral incision is marked over the hip before surgery begins. The illustration shows the underlying bony anatomy — the ilium, greater trochanter and proximal femur — and the relationship of the planned incision to these landmarks. The incision is centred over the posterior aspect of the greater trochanter and curves gently to give access to the deep structures below.

Intraoperative illustration showing the posterior hip approach with the greater trochanter, gluteus medius, gluteus minimus and piriformis labelled

Posterior approach exposure. The greater trochanter is identified centrally. The abductor muscles — gluteus medius (G. medius) and gluteus minimus (G. minimus) — are retracted superiorly to protect them throughout the procedure. The piriformis and short external rotators are visible inferiorly; these are divided to access the posterior capsule and are repaired at wound closure to restore stability.

The Posterior Approach

Mr. Lodge performs total hip replacement through a posterior approach — an incision centred over the posterolateral aspect of the hip that allows excellent visualisation of both the acetabulum (socket) and the proximal femur (thigh bone) while preserving the abductor muscles entirely.

The patient is positioned on their side (lateral decubitus). The incision is made through the skin and subcutaneous tissue, and the deep fascia is divided to expose the greater trochanter and the underlying musculature. The gluteus medius and minimus — the critical abductor muscles responsible for pelvic stability during walking — are carefully retracted upward and protected throughout the entire procedure.

The piriformis and short external rotators are then divided close to their femoral attachment, revealing the posterior hip capsule beneath. The capsule is incised, and the hip is carefully dislocated by internal rotation and flexion of the leg.

Abductor muscles (G. medius and G. minimus) are never divided — retracted and protected throughout
The posterior capsule and short external rotators are repaired at closure — a key step in reducing the risk of post-operative dislocation
The posterior approach gives outstanding access to both the socket and the femoral canal

2

Stage Two

Dislocation & Neck Resection

Delivering the Arthritic Femoral Head

After the capsule is opened, the hip is dislocated by internally rotating and flexing the leg — a controlled manoeuvre that levers the femoral head out of the acetabular socket and into the wound. The arthritic femoral head becomes visible in the operative field exactly as illustrated.

What is immediately apparent in cases of established osteoarthritis is the destruction of the articular cartilage surface. The normally smooth, glistening white cartilage that should cover the femoral head has been lost entirely, replaced by sclerotic, eburnated bone — bone rubbing directly on bone. The characteristic deformities of advanced arthritis — osteophytes, cysts and surface irregularity — are clearly visible at this stage.

The femoral neck is then resected at a carefully planned level using an oscillating saw. The angle and height of this cut determine the leg length and offset of the reconstruction, and are planned pre-operatively using templated X-rays.

The arthritic femoral head is removed and sent for histological examination as routine
The neck resection level is pre-templated to restore leg length and offset accurately
Once the femoral head is removed, the acetabulum (socket) is fully exposed and ready for preparation

Intraoperative illustration showing the dislocated arthritic femoral head delivered into the wound, surrounded by retractors

The dislocated femoral head. The arthritic femoral head has been delivered into the wound following posterior dislocation. The destroyed articular surface — with complete loss of cartilage and exposure of the underlying bone — is clearly visible. Retractors hold the operative field open around the joint.

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Stage Three

Acetabular Preparation

$Intraoperative illustration showing the arthritic acetabulum exposed between retractors, with the destroyed cartilage surface and eburnated bone visible before reaming$

The arthritic acetabulum. The socket is exposed between retractors. The articular cartilage has been completely destroyed by osteoarthritis — the surface is irregular, eroded and sclerotic. This is the appearance of the socket before reaming begins. Seeing the raw anatomy at this stage helps the surgeon plan the depth and orientation of reaming required to restore a true hemispherical cavity.

Illustration of the uncemented acetabular shell on its impactor, showing the porous-coated outer surface and screw holes, ready for insertion

The acetabular shell. An uncemented porous-coated hemispherical metal cup on its impactor, ready for insertion into the prepared socket. The rough, textured outer surface allows bone to grow directly onto the implant. Screw holes allow supplementary fixation into the ilium if required.

Reaming the Socket

With the femoral head removed, the acetabulum is exposed between retractors and prepared using a series of hemispherical reamers — rotating cutting tools that enlarge the socket incrementally to the precise diameter required for the chosen implant.

Reaming removes the remaining arthritic cartilage and the thin layer of sclerotic bone beneath it, exposing healthy, bleeding cancellous bone that will form a biological bond with the porous surface of the uncemented cup. The goal is to achieve a hemispherical cavity of exactly the right size — precise to within a millimetre — in the correct position and orientation.

The orientation of the socket — its inclination (the angle from vertical) and anteversion (the forward tilt) — is critical. Incorrect orientation is one of the most common causes of impingement, instability and early failure of hip replacement. Mr. Lodge uses anatomical landmarks and, where indicated, robotic or navigation assistance to confirm optimal positioning.

Sequential hemispherical reamers prepare the socket to the correct size
Target inclination approximately 40° and anteversion approximately 15–20°
The bleeding cancellous bone surface allows biological ingrowth onto the porous cup
Orientation is confirmed using anatomical landmarks and intraoperative assessment

4

Stage Four

Acetabular Cup Insertion

Illustration of the acetabular cup being impacted into the reamed socket, showing the porous surface against the bone

Cup impaction. The acetabular shell is driven into the prepared socket using a mallet and impactor, achieving a tight press-fit. The cup is seated at the correct inclination and anteversion. Supplementary screws may be added where additional initial stability is required.

Intraoperative illustration showing the femoral head component being assembled onto the stem taper

Assembling the femoral head. The ceramic femoral head is being introduced and will be impacted firmly onto the Morse taper of the femoral stem. Head size — typically 36 mm — is selected to optimise stability and minimise dislocation risk while controlling bearing wear.

$Intraoperative illustration showing the reamed acetabular socket with the acetabular shell impactor being seated, viewed from the surgeon's perspective$

The reamed acetabulum. The hemispherical socket precisely prepared and ready to receive the cup. Retractors hold the soft tissues and give the surgeon an unobstructed view of the acetabulum throughout seating and orientation checks.

Intraoperative illustration showing the seated acetabular cup with polyethylene liner in place, viewed from the surgeon's perspective

Cup seated with liner. The metal shell is firmly press-fit in the socket and the highly cross-linked polyethylene liner — the bearing surface — has been locked into place. This is the surface on which the ceramic femoral head will articulate.

Seating the Acetabular Component

The acetabular shell — a hemispherical titanium cup with a roughened, porous outer surface — is pressed firmly into the prepared socket using a mallet and impactor. The cup is slightly larger than the reamed cavity (typically by 1–2 mm), so that when driven in it is held by the surrounding bone under compression — the "press-fit" principle that provides immediate mechanical stability while biological fixation develops over the following weeks.

Once the shell is seated at the correct orientation and confirmed to be stable, the highly cross-linked polyethylene liner is locked inside it. Additional fixation screws may be placed through the shell into the ilium where extra security is required — for example in revision cases or in bone of lower density.

Uncemented vs cemented cup fixation: Mr. Lodge uses uncemented fixation for the acetabular cup in the majority of patients. The biological bond that develops between the porous implant surface and the host bone is highly durable. In elderly patients with significantly osteoporotic bone, cemented fixation may occasionally be preferred.

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Stage Five

Femoral Canal Preparation

Preparing the Femoral Canal

Attention then turns to the femur. The leg is positioned to bring the femoral canal into the operative field — typically by placing the leg into a "figure-of-four" position (knee flexed and internally rotated) that presents the proximal femur to the surgeon.

The femoral canal is opened at the neck resection surface and progressively enlarged using a series of broaches — shaped metal files that rasp the inner cortical surface of the femur to create a cavity precisely matching the geometry of the chosen implant. Each broach is slightly larger than the last, and the process is continued until the broach is firmly seated in the canal without toggling — indicating a good cortical contact that will provide initial stability.

Trial components are then placed — a trial broach with a trial femoral head of the appropriate diameter and neck length — and the hip is reduced to assess leg length, offset, soft tissue tension and the range of movement before dislocation. This "trial reduction" allows any necessary adjustments to be made before the definitive implants are selected and fixed.

Progressive broaching creates the precise canal geometry for the chosen implant
Trial reduction confirms leg length, offset, stability and range of motion before final implantation
Multiple neck length and offset options allow fine-tuning of the reconstruction
The canal is thoroughly irrigated before final stem insertion

Intraoperative illustration showing the femoral canal being prepared with the leg in a figure-of-four position and the proximal femur visible between retractors

Femoral canal preparation. With the leg positioned to present the femoral canal, the proximal femur is exposed between retractors. The broaching process prepares the canal to match the geometry of the femoral stem implant. The surrounding subcutaneous tissue and muscle are protected by retractors throughout.

Intraoperative illustration showing the seated acetabular cup with liner following trial reduction, with soft tissues visible around the implant

Trial reduction. Following broaching and trialling, the hip is reduced to assess leg length, offset, soft tissue tension and stability before the definitive implants are fixed. This is the view the surgeon sees during trial reduction — confirming the reconstruction is optimal before final component selection and definitive fixation.

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Stage Six

Femoral Stem Insertion

Intraoperative illustration showing the femoral broach being driven into the femoral canal with a mallet, the wound held open by retractors with surgical drapes visible

Femoral stem insertion. The definitive femoral stem is driven firmly into the prepared canal using a mallet and inserter. The stem follows the path established by sequential broaching and is seated until it is secure at the planned depth and rotational alignment. The wound is held open by retractors throughout, with surgical drapes framing the operative field.

Implanting the Femoral Stem

Once trial reduction has confirmed the optimal reconstruction, the femoral canal is thoroughly washed out with pulsed lavage and the definitive femoral stem is introduced. The stem is driven carefully into the canal using a mallet and inserter, following the path established by the broaches, until it is seated at the correct depth and rotational alignment.

For an uncemented stem, the fit is confirmed by the changing sound and feel of the mallet blows — a firm, high-pitched "ring" indicates good cortical engagement and stable seating. Cementing technique, when used, involves pressurising bone cement into the canal before stem insertion, which fills the trabecular spaces and creates a strong mechanical bond between stem and bone.

The femoral head component — ceramic or metal, chosen to match the bearing combination selected for this patient — is then impacted firmly onto the taper at the top of the stem. The taper junction (Morse taper) is a cold-weld connection: the two metals are driven together under force, and the resulting junction is highly resistant to separation.

The stem is introduced along the axis of the femoral canal established by broaching
Rotational alignment is controlled to optimise stability and range of movement
The femoral head is impacted onto the Morse taper — a cold-weld connection requiring significant force to separate
Head diameter (typically 36 mm) is selected to optimise stability and minimise dislocation risk

7

Stage Seven

Reduction & Wound Closure

Completing the Reconstruction

With both components implanted and confirmed to be stable and correctly positioned, the hip is reduced — the femoral head is brought back into the acetabular cup by externally rotating and extending the leg, reversing the dislocation manoeuvre performed at the start of the procedure.

The stability and range of movement of the reconstruction are then carefully assessed. The hip is taken through a full arc of flexion, extension and rotation to confirm that the components do not impinge on each other or on the surrounding bone, and that the hip cannot be dislocated within the range of normal daily activities. Any adjustments to component position are made at this stage before definitive closure.

The posterior capsule and short external rotators — divided at the start of the procedure — are then repaired back to the greater trochanter using strong sutures. This posterior capsular repair is a critical step that significantly reduces the risk of post-operative dislocation, and is performed meticulously at the end of every case. The wound is then closed in layers using absorbable buried sutures with wound glue over the wound to achieve a watertight closure. Very rarely, allergic reactions can occur to the glue — this typically presents as a rash. Whilst it is important to get this reviewed, it is typically very easily and quickly managed with a low-dose topical steroid cream. Please make your surgeon aware if you have had reactions to topical skin glues with previous surgeries, or equally to nail glues used for cosmetic nail extensions. A waterproof dressing is applied.

Stability and impingement-free range of movement are confirmed before closure
Posterior capsule and short external rotators are repaired to the greater trochanter — key to post-operative stability
Wound closed in layers with absorbable buried sutures and wound glue; waterproof dressing applied
Total operative time typically 90 minutes to two hours

After closure: The patient is transferred to the recovery room, where they are closely monitored as the anaesthetic wears off. Most patients are sitting up and beginning to mobilise with a physiotherapist within a few hours of leaving theatre. For more on the post-operative journey, see the Your Operation page.

Illustration showing the completed hip replacement viewed from outside the body, with the implanted components visible within the pelvis and the wound closed

The completed reconstruction. A surface view of the reconstructed hip showing the relationship of the implanted components to the surrounding bony anatomy of the pelvis. The new femoral head sits securely within the acetabular socket, restoring the normal geometry and biomechanics of the hip joint. The wound layers have been closed, and the patient is ready to begin recovery.