Prehabilitation, short stem, anterior approach = one treatment pathway

ARTIQO: Please help us understand: Why is prehabilitation important?

Prof. Zilkens: In endoprosthetics, we primarily deal with elderly patients. Sarcopenia, the increasing muscle loss associated with aging, is a major issue. From the age of 30, we humans lose approximately 10% of our muscle mass per decade. This can be a life-limiting factor that we have surprisingly neglected in the past.

The goal of prehabilitation is to significantly improve our patients’ fitness before surgery, following the motto: “Better in, better out.” In our OGPaedicum practices, we routinely use BFR training, or blood flow restriction training, for targeted muscle building.

ARTIQO: How does this special training work and what effect does it have?

Prof. Zilkens: Simply put: Only heavy weights build big muscles. Everything else is cardio. However, patients who need a hip or knee replacement often struggle to lift heavy weights and therefore cannot build muscle effectively.

With bloat restriction (BFR) training, the muscles work under oxygen deprivation. This makes it possible to increase muscle strength and mass with low resistance.

We achieve this restriction of blood flow using special cuffs that are worn around the legs during training. This simulates a high workload. Imagine it like this: If you cycle for 15 minutes with the cuff around your thigh, it has the effect of crossing the Andes. In reality, you’ve only cycled to the nearest kiosk. This means we can offer patients with joint problems intensive strength and endurance training in this way.

ARTIQO: Are there any restrictions regarding which patients the training is suitable for?

Prof. Zilkens: We can use BFR training to effectively prepare patients of all ages for surgery. Ultimately, the usual limitations apply: no pulmonary embolism or thrombosis, no serious heart conditions, and no severe circulatory disorders.

ARTIQO: How exactly does the training work?

Prof. Zilkens: All our patients undergo structured pre-operative preparation. In addition to various training sessions—for example, on the safe use of forearm crutches and other assistive devices—they are offered the opportunity to participate in BFR training at one of our Sports Medicine Institute’s locations near their home. Ideally, this training begins about six weeks before the operation—the earlier, the better.

The patient is actively involved in the treatment process. They transition from being a prosthesis recipient to an active partner on their journey to an active and pain-free life. This requires training before and after the operation, and ideally, lifelong.

ARTIQO: What other standards do you have?

Prof. Zilkens: My approach to the approximately 300 hip replacements I implant each year is always the same: minimally invasive direct anterior approach (DAA/AMIS) with muscle preservation, short stem, preferably cementless, and ideally ceramic-on-ceramic. Since I operate in four different hospitals, I prefer simple and structured procedures before, during, and after the surgery: supine positioning without an extension table, draping with a horizontal film similar to gamma nailing, so that I can manage with minimal assistance. There are few specialized instruments for the approach. I do the washing, suturing, and applying the dressing myself. The shower dressing stays in place for 14 days; no dressing changes, no drainage. During my evening rounds on the day of surgery, I ensure that the patient is mobilized; if necessary, I do it myself. We achieve transition times of approximately 30 minutes (sewing-to-incision time) without any rush, so I can usually perform five hip replacements in one operating room before 3:00 PM without parallel inductions or a second anesthesia team. That’s a fantastic team effort.

ARTIQO: What advantages do our shafts offer you?

Prof. Zilkens: In 2009, I discovered and fell in love with short-stem prostheses and have been using them as my standard implant for many years. Preserving bone at the femoral neck, the physiological force transmission to the proximal femur, the ease of handling during implantation, and the protection of the greater trochanter make the short-stem prosthesis an ideal implant, especially when using the DAA/AMIS approach.

A huge advantage of the A2® short-stem system is that I have the option of easily switching to the cemented stem variant intraoperatively if the bone quality is poor. What a luxury to know from the outset that my planned preventative strategy will be successful!

ARTIQO: How does the pan compare in terms of “simplicity”?

Prof. Zilkens: The ANA.NOVA® cup works perfectly and locks circumferentially even in challenging bony conditions. From 50 mm upwards, I can use a 36 mm head. The insertion instrument is well-designed and easy to use. In borderline cases, especially with dysplasia or bone defects, I prefer to use the hybrid cup; the acetabular wings are particularly helpful in achieving primary stability when there is insufficient bony preload. Both cups demonstrate excellent long-term results.