How to Perform Hemi Hip Arthroplasty - Posterior Approach

Step 1. Posterior incision

line is planned symmetrical to the anterior one.

Step 2. Anterior incision

The aim is to reach the bone surface by advancing through the skin, subcutaneous tissue, and muscle tissue, ensuring a clean, precise cut that promotes healing. To manage bleeding, complete the anterior incision down to the bone before starting with the posterior incision. The skin incision is made with a scalpel following the anterior side markings. The deeper soft tissues are then divided mainly using the coagulating diathermy. The tendons can be cut through using the cutting mode of the diathermy. The soft tissue cutting should be made slightly oblique inward. This is to help with the closure: It can be challenging to fit excessive muscle and fat tissue under the closure. Larger vessels on the anterior side (e.g. The great saphenous vein medially in the subcutaneous tissue) are ligated, smaller ones are coagulated using diathermy or electrocautery. When you reach the bone surface anteriorly, the diathermy can be used to peel the soft tissue off the bone to prepare it for the sawing.

Step 3. Posterior incision

The incision on the posterior side is managed in the same way as the anterior side. The sciatic nerve and major vessels of the thigh are accessible from the posterior flap side. The goal is to expose the bone surface, identifying the sciatic nerve and major vessels need to be dealt with separately. While an assistant can holds the leg up, advance sharply through the skin and subcutaneous tissue to the fascia level. The medial and lateral corners of the incision should be handled carefully to avoid unwanted cuts outside of the planned incision line for better healing. Then advance deeper in the muscle tissue using the diathermy. The posterior side tendons can be cut, again, using the cutting mode of the diathermy. The sciatic nerve is located posteriorly, laterally from the femoral vascular line. The nerve can first be cut sharply and left longer and shortened later. At the same time, before the nerve retraction, hemostasis can be done to the interneural artery. Marking the nerve sheath, for instance with Crile forceps, can be beneficial for the upcoming placement of an anesthetic catheter. Make sure not to apply pressure on the nerve itself. Advance through the posterior muscles tissue until the femoral vessels on the posteromedial side of the thigh have been identified.

Step 4. Ligation of the femoral vessels

The goal is to securely ligate the femoral vessels requires a proper technique to avoid ligature slippage and potential hemorrhage. Separating and individually ligating the femoral artery and vein is done to reduce the risk of AV fistula formation. On the posterior flap side identify the femoral artery and vein which run medially near the bone. With blunt dissection, isolate the vessels from the surrounding tissue. The femoral artery and vein on the remaining side are separately ligated using the transfixing ligation method with a non-absorbable synthetic suture (e.g. Prolene) of size 2-0. Use multiple knots. Consider making a double ligation for the artery, for example with 2-0 Vicryl distal to the Prolene suture. A simple suture ligation (for example with Vicryl sutupak 2-0) is suitable for the distal or outgoing side of the vessels. The patient might have foreign material from previous vascular procedures. Venous and prosthesis grafts can be ligated like regular vessels: proximally with a ligature, with stumps kept short to minimize the amount of foreign material. If an arterial stent is present, it can be gently removed out of the cut surface or ligated over. Once the ligations have been securely achieved, make sure that the bone is exposed enough for the division.

Step 5. Sawing the bone

The aim is to cut through the femoral bone at an appropriate level regarding the closure and smooth the cut bone edges to prevent tissue damage. Remove all tissue circumferentially covering the bone, freeing up the sawing surface. The periosteum can also be pushed in the proximal direction using a rasp. A soft tissue protector is put in place prior to the sawing. The sawing is done perpendicular to the bone with a bone saw (i.e. Gigli saw or oscillating electric/pneumatic saw). If necessary, sharp edges of the bone can be trimmed with a rongeur or a side cutter. The femur's edge is smoothed using a file. Once the bone is cleared, use diathermy to finalize hemostasis. Some small arteries may also require figure-of-8 sutures to ensure complete hemostasis.

Step 6. Placement of the sciatic perineural catheter

The goal is to accurately and safely place the pain pump's catheter in close proximity to the sciatic nerve and secure it properly to prevent dislodgement post-procedure. Insert the anesthetic catheter near the sciatic nerve by penetrating the skin of the posterior flap with a puncture needle. Remove the needle from the sleeve and put the catheter into place. Try to slide the catheter along the nerve a bit further, if possible. Finally, remove the sleeve by splitting it, while gently pushing the catheter inwards. Tape the outside remaining part of the catheter securely on the skin. At this stage, the sciatic nerve can also be shortened sharply if it has been left long. Remember intraneural hemostasis, before you let the nerve pull into the proximal soft tissue. Hemostasis and planning the closure Check that the hemostasis has been achieved. If needed, use diathermy or figure-of-8 sutures for resilient bleeders. Plan the closure approximating the anterior and posterior flap and check that the tissue aligns nicely and that the end result is symmetrical. If needed, remove bulging muscle or subcutaneous tissue.

Step 7. Closure

The aim is to achieve a secure, well-vascularized, tension-free closure that promotes healing, minimizes the risk of infection, and results in well-contoured stump. Muscles are approximated loosely with figure-of-8 sutures, but in such a way that the tissue surfaces clearly come into contact. A large needle, which is easier to handle in thick tissue mass, should be chosen for the thread (e.g. Vicryl 0). The fascia is approximated with interrupted sutures (e.g., Vicryl 0). It is advisable to carry out the sutures sector by sector to ensure a symmetrical closure. For the subcutaneous closure, start by applying U-shaped knots using, for example, Vicryl 2-0. These sutures should be symmetrically spaced and initially widely apart. Bring the anesthetic catheter, which will be positioned subcutaneously, through the skin. This is done by puncturing the skin with a needle and introducer. Thread the anesthetic catheter between the previously placed subcutaneous sutures. Once the catheter is properly positioned, proceed to add U-stitches to every alternate gap between the existing sutures. Close the skin using non-absorbable single sutures with a 3-0 thread, ensuring the skin edges meet. The sutures should be evenly spaced - not too far apart to prevent sagging with potential swelling, but also not too close together to avoid compressing the wound and hindering healing.

Step 8. Excessive femur length post-amputation

If the femur is left excessively long relative to the surrounding soft tissue, it can potentially protrude through the wound over time, particularly in older patients who have fragile and thin soft tissues. This is due to the sharpness of the bone edge compared to the soft tissues. In these cases, a revision surgery might be required.