Why your condition before surgery shapes what happens after

The NHS now discharges most patients after hip replacement within roughly four days — down from a week in 2004, following the widespread adoption of Enhanced Recovery After Surgery (ERAS) protocols. That compressed timeline means the fitness and muscle strength a patient brings into the operating theatre matter considerably more than they once did. There is less time on the ward to recover baseline function; the work starts before the operation begins.

The clearest evidence for why this matters comes from a 2002 study by Fortin and colleagues, cited in subsequent rehabilitation research: patients with low preoperative function were approximately five times more likely to require assistance with activities of daily living — washing, dressing, moving around the home — at 24 months after hip replacement compared with patients who entered surgery with higher function. That is a large difference, and it makes the preoperative window a meaningful opportunity rather than simply a waiting period.

On the question of whether structured exercise actually shifts that baseline, a 2023 systematic review and meta-analysis by Punnoose and colleagues, drawing on 48 randomised controlled trials, found moderate-certainty evidence that prehabilitation improves health-related quality of life scores and hip abductor strength in total hip replacement candidates before surgery. That is an encouraging signal. The same review, however, found only weak evidence that these preoperative gains translate into significantly better outcomes after the operation — an important qualification that should be stated plainly rather than glossed over.

The honest framing is this: prehabilitation is preparation, not a guarantee. A patient who arrives at surgery with stronger hip stabilisers, better cardiovascular fitness, and greater confidence in using a walking aid is better placed to mobilise early in the postoperative period — and early mobilisation is where functional recovery begins.

Hip abductor strength — the most important muscle group to train

Every step involves a brief moment when one foot leaves the ground entirely. During that fraction of a second, the gluteus medius and gluteus minimus — the two primary hip abductors — contract on the stance side to hold the pelvis level. Without adequate strength in these muscles, the pelvis drops toward the unsupported side. That drop is the Trendelenburg sign, and the characteristic compensatory lurch it produces is the limp most patients with advanced hip osteoarthritis recognise in themselves.

The problem tends to worsen progressively before surgery. As hip pain increases, patients unconsciously offload the affected side — reducing the distance walked, avoiding stairs, shifting weight during standing. This pain-avoidance pattern is understandable, but it causes the hip abductors to weaken through disuse at precisely the time when their strength is most clinically relevant. By the time surgery is scheduled, many patients arrive with meaningful atrophy in these muscles on top of whatever deficit the arthritis itself has caused.

Targeting the gluteus medius and gluteus minimus in the weeks before hip replacement therefore addresses the most common functional deficit patients bring into the operating theatre. It is also the area where prehabilitation has its strongest mechanistic rationale: the same muscles that stabilise the pelvis before surgery are those that govern gait quality and independence afterwards.

Specific numerical targets — such as a minimum abductor strength in Newton-metres per kilogram — are not yet codified in current clinical guidelines. Practical goals are more useful markers: a visible reduction in the Trendelenburg sign during slow walking, the ability to hold a single-leg stance for several seconds without the pelvis dropping, and progressive tolerance of side-lying abduction exercises against resistance. These functional milestones reflect the direction of travel without overstating what the evidence can currently specify.

Gait quality and single-leg balance as readiness markers

A muscle that has grown stronger can still fire in the wrong sequence. The trunk lean, shortened stance phase, and hip drop that develop during months of hip pain are not purely the result of weakness — they become movement habits that the nervous system continues to execute even after the pain stimulus changes. Gait re-training before surgery therefore matters as a distinct intervention from strengthening: the neuromuscular pattern itself needs correcting, not only the underlying muscles.

Single-leg stance is a practical window into this dimension of readiness. Holding a controlled, level pelvis on one leg for several seconds — without excessive trunk sway or compensatory lean — reflects proprioceptive integration as much as muscle bulk. Patients who struggle with this entering surgery have a stability deficit that targeted balance and weight-shifting work, run alongside strengthening, can start to address. No equivalent scored threshold for balance has been established in clinical guidelines; the directional goal is a controlled, unhurried stance that the patient can reproduce rather than a timed performance figure.

Preoperative physiotherapy focused on movement quality may include controlled weight-shifting progressions, single-leg work on stable then gradually less predictable surfaces, and guided attention to trunk position during slow walking. Where a patient has developed a marked lateral lean or shortened stance phase on the affected side, addressing those patterns before surgery gives the neuromuscular system a more accurate template to draw on when early postoperative gait practice begins.

One practical step that is sometimes overlooked is walking-aid technique. Patients already using a stick or crutches before surgery often do so reactively, gripping for reassurance rather than executing a controlled weight transfer. Practising correct mechanics before the operation means that postoperative mobilisation — which under ERAS protocols typically begins within hours of hip replacement — involves a familiar movement rather than one learned for the first time under anaesthetic after-effects.

Cardiovascular fitness and walking capacity before surgery

Cardiovascular fitness is not simply about how quickly a patient gets back on their feet after hip replacement — it is a clinical variable that influences anaesthetic tolerance, wound healing, and the body's capacity to manage the physiological stress of surgery itself. Patients who enter the operating theatre with poor aerobic reserve tend to find early postoperative mobilisation more taxing, and that difficulty compounds at a time when the recovery programme is already demanding.

One monitoring tool patients may encounter during prehabilitation is the six-minute walk test (6MWT), which asks how far a person can walk at their own pace in six minutes. In arthroplasty research, the 6MWT has been used as a measure of functional walking capacity and cardiovascular endurance before and after surgery. It is worth understanding, however, that no single agreed minimum distance currently defines surgical readiness in clinical guidelines. Its value is as a progress marker — a way of comparing where a patient stands today with where they stood four or eight weeks earlier — rather than as a fixed pass-or-fail threshold.

For most patients with hip osteoarthritis, even moderate-intensity aerobic conditioning is sufficient to produce meaningful cardiovascular benefit. Stationary cycling, brisk walking on flat ground, and aquatic therapy all provide cardiovascular stimulus without the impact loading that advanced arthritis makes difficult. A practical self-monitoring goal is sustainable walking distance — the furthest a patient can walk continuously before pain forces a rest — tracked informally over weeks.

Patients with cardiac, respiratory, or other significant comorbidities should have their aerobic conditioning targets set alongside their clinical team rather than through self-directed benchmarks, as the appropriate intensity and mode of exercise will depend on their wider medical picture.

Exercise modalities that work when the hip is painful

Most patients arriving at prehabilitation have already scaled back their movement to protect a painful hip. The aim of the exercise programme is to reintroduce mechanical loading in a controlled, tolerable way — and the choice of modality matters.

Stationary cycling and aquatic therapy move the hip through its available range and stimulate the joint mechanically without the impact loading that arthritic cartilage cannot comfortably absorb. In water, buoyancy reduces effective body weight, allowing patients to work at a muscular intensity that would be painful on dry land. Alongside these, targeted resistance exercises — side-lying abduction, clamshells, mini-squats, and seated hip work — reach the hip abductors and quadriceps without requiring the patient to load heavily through a sore joint. Structured protocols typically use around 70–75% of one-repetition maximum to generate a genuine training stimulus.

A well-designed programme builds in layers. The first addresses range of motion and pain-managed movement, keeping the joint mobile without provoking it. The second introduces progressive loading through the exercises above. The third moves towards functional tasks — practising transfers, stair work, and walking on uneven surfaces — that directly mirror what the early post-operative days will demand.

Surgical readiness also involves a small number of non-exercise factors worth naming properly. Smoking reduces tissue oxygenation and slows wound healing; even a short period of cessation before surgery produces measurable benefit. Adequate protein intake supports muscle protein synthesis during training and tissue repair after the operation. Weight optimisation, where relevant, lowers mechanical load on the new implant and reduces anaesthetic risk. These are typically addressed through pre-operative preparation appointments alongside the exercise component.

Prehabilitation as part of the Lincolnshire Hip pathway

The Rapid Biological Recovery® programme at Lincolnshire Hip treats prehabilitation not as a separate preparation phase but as the opening chapter of a continuous perioperative strategy. Personalised muscle conditioning and nutritional guidance begin locally — through pre-operative appointments in Sleaford or Grantham — so that the training window opens well before any surgical date is confirmed. Lincolnshire Hip is part of the MSK Doctors group and accepts patients without a GP referral for an initial hip assessment, which means the process can start as soon as it is clinically appropriate rather than waiting for a theatre slot.

The connection to the surgical technique is worth making explicit. The SPAIRE approach, as used by Professor Paul Lee, is designed to preserve the short external rotators at the time of hip replacement, minimising soft-tissue disruption at the point of surgery. Because the operation is planned around that principle, the muscular condition a patient brings into theatre has a direct bearing on the biological environment the surgeon works within — and on how quickly the body can respond afterwards. Pre-operative muscle quality is not incidental to the SPAIRE pathway; it is part of its logic.

A physiotherapist-led assessment at the start of the programme establishes individual baseline measures: current hip abductor strength, walking tolerance, single-leg balance, and movement quality. These become the reference points against which weeks of structured training are tracked — concrete markers of progress, not approximations.

1. [1] Hip replacement. https://en.wikipedia.org/?curid=1125423 https://en.wikipedia.org/?curid=1125423
2. [2] Prehabilitation. https://en.wikipedia.org/?curid=23758579 https://en.wikipedia.org/?curid=23758579