The first 48 hours: what is normal and what to do

Some discomfort in the hours after a Liquid Cartilage™ hip injection is a normal part of the process, not a sign that something has gone wrong. Once the local anaesthetic wears off — typically two to four hours after the appointment — most patients notice localised aching, mild stiffness, and a sense of fullness or swelling around the hip joint. This is an expected inflammatory response and usually peaks within the first 48–72 hours before beginning to settle.

The collagen scaffold (ChondroFiller™) self-gels within approximately three to five minutes of being placed inside the hip joint, bonding to the body's natural fibrin network. Keeping the hip relatively calm in those early hours and the following day allows that initial stabilisation to complete undisturbed — which is why some restriction matters biologically, not just for comfort.

Pain management

Paracetamol is the recommended first-line option for managing post-injection soreness. A short course of ibuprofen — typically for seven days — is also appropriate to reduce inflammation, provided there are no contraindications such as kidney disease, stomach ulcers, or allergy. Take both at the doses on the packet; do not exceed the stated maximum.

Movement and rest

• Relative rest means protecting the hip from heavy loading — not strict bed rest. Gentle walking around the home is fine and actually helps circulation.
• Avoid prolonged standing, strenuous walking, heavy lifting, or any activity that causes sharp hip pain.
• Do not drive on the day of the injection. Most patients can manage short journeys from day two, once comfort allows and no sedation was used.
• Avoid vigorous sport or gym exercise for the first 14 days.

Weeks one to six: the Protect phase

The six weeks following a Liquid Cartilage™ hip injection at Lincolnshire Hip are formally called the Protect phase — and the label is deliberate. Inside the hip joint, the collagen scaffold is consolidating its early position and beginning to draw in the body's own repair cells; disrupting that process with heavy loading could compromise integration before it has properly established.

For patients on the outpatient ultrasound-guided injection route, the practical experience is considerably lighter than many anticipate. Returning to light daily activity within one to two weeks is realistic — a meaningfully faster trajectory than recovery from hip arthroscopy or hip replacement surgery, where timescales are measured in months.

What is permitted

From around week two, short flat walks are appropriate and support joint circulation. Gentle range-of-motion exercises — slow hip circles, supported flexion — can begin as tolerated. Swimming is generally suitable from a similar point, provided you use a minimal-kick technique to avoid placing sudden load through the hip. Always confirm specific timings with the clinical team before restarting any exercise.

What to avoid throughout this phase

• Running, jumping, or high-impact exercise of any kind
• Heavy lifting
• Any activity that reproduces sharp hip pain

These restrictions apply for the full six weeks, regardless of how quickly early soreness settles. Pain and stiffness typically trend downward across weeks two to six, though day-to-day variation is entirely normal — a rougher day does not mean recovery has stalled.

Weeks six to twelve: rebuilding hip strength

Around week six, the balance of the recovery programme shifts — from protecting the scaffold to actively rebuilding the strength around it. This is not a sudden change of pace but a gradual rebalancing of priorities, with physiotherapy guidance becoming the central thread of daily progress.

Sessions in this phase typically focus on the muscles that stabilise the hip joint: principally the gluteus medius and gluteus minimus on the outer hip. These structures are the ones that offload the joint during walking and single-leg weight-bearing, and strengthening them reduces the mechanical demand on the regenerating cartilage surface, supporting longer-term function.

Activities and progression

• Stationary cycling is well suited to weeks six to eight: it loads the hip through a controlled range without impact, and resistance can be increased incrementally as strength builds.
• Swimming can be progressed in technique and intensity from where it was introduced earlier in recovery.
• Walking on flat, even ground should extend in duration and pace — gradual, measurable increments rather than a single ambitious outing.

The exact timeline for each activity should be agreed with the physiotherapist supervising the programme. Pushing ahead of the progression schedule is one of the more common causes of setbacks: the scaffold may feel settled, but the tissue forming within it is still maturing and does not yet tolerate sudden increases in load. Range-of-motion exercises continue alongside strength work — slow, supported hip movements that restore confidence in the joint without forcing it.

By week twelve, a recognised biological milestone has been reached: cells that have migrated into the collagen scaffold are actively differentiating into chondrocytes — the specialised cells responsible for cartilage. That turning point matters, but it is not the end of the process. Functional improvement and continued filling of the cartilage defect carry on well beyond this mark, typically across the full first twelve months.

What is happening inside the hip joint at twelve weeks

By twelve weeks, a recognised cellular milestone has been reached — but structural repair inside the hip joint continues for considerably longer, and understanding the mechanism explains why.

ChondroFiller™ is an acellular scaffold: it contains no cells of its own. Rather than delivering cartilage-forming cells directly, the injectable collagen matrix works by providing the structural and biological environment that recruits the patient's own progenitor cells from surrounding tissue. This process — acellular matrix-induced chondrogenesis — depends on time and a protected mechanical environment to establish properly, which is why the Protect and Strengthen phases exist as distinct, sequenced stages rather than a single undifferentiated rest period.

The twelve-week point matters because those recruited progenitor cells are by now differentiating into chondrocytes — the specialist cells that build and maintain cartilage. Structurally, however, the picture at twelve weeks is not complete. Clinical evidence from ChondroFiller studies shows MOCART scores — a radiological measure of cartilage defect filling — rising from approximately 65 at four weeks to over 80 at one year. Defect filling and tissue maturation continue to advance in the months that follow, well past the twelve-week mark.

Over one to two years, the scaffold itself is gradually resorbed and replaced by the patient's own native cartilage. Inside the hip joint — where the femoral head sits within the acetabulum and smooth articular cartilage makes low-friction movement possible — the goal of treatment is to support that endogenous repair rather than to substitute for it permanently. Continued patience past twelve weeks is not passive recovery; it is when the most sustained structural change occurs.

Clinical evidence: what outcomes patients report

The question most patients ask before committing to treatment is whether the evidence actually supports what the procedure promises — and for Liquid Cartilage™, the published outcome data provide a reasonably clear picture, with some honest caveats worth stating upfront.

Patient-reported outcome scores — measured using the IKDC functional index and the modified Harris Hip Score (mHHS), which captures hip-specific pain and mobility — consistently improve by approximately 30 points over twelve months. This figure sits well above the Minimal Clinically Important Difference threshold of 16.7 points, meaning it represents a change patients would notice and value in daily life, not merely a statistical signal. Improvement is not front-loaded: scores rise progressively from four weeks through to the twelve-month mark and beyond, consistent with the gradual biological process of cellular recruitment and tissue maturation.

On safety, the reported adverse-event rate across ChondroFiller's clinical programme is approximately 0.06%. The events recorded are predominantly transient — in most cases a short-lived local flare-up within the treated joint in the days following the injection, resolving without lasting consequence. Individual risk varies with clinical circumstances and is best explored at consultation, but the overall tolerability profile is strong.

Two limitations are worth stating plainly. First, dedicated hip-specific randomised controlled trial data are limited; the evidence draws on clinical programme data and studies conducted predominantly in other joints. Patients should calibrate expectations accordingly. Second, the treatment is appropriate for selected patients with focal or mild-to-moderate hip cartilage degeneration — it is not indicated for advanced osteoarthritis where hip replacement is the appropriate clinical answer.

Practical support for Lincolnshire patients

For patients in Lincolnshire, the practical distance from specialist hip care is shorter than it might seem. Lincolnshire Hip holds consultations at two local clinics — in Grantham and in Sleaford — so neither initial assessment nor follow-up appointments require a journey to London. Post-injection physiotherapy, which carries patients through the Strengthen phase from week six onwards, is also available locally, removing one of the logistical barriers that can slow rehabilitation.

At the consultation, Professor Paul Lee will review your imaging and clinical history, confirm whether the Liquid Cartilage™ injectable pathway is appropriate for your hip, and walk through the individual protocol — including which biological adjuncts such as PRF or PRP may be added alongside ChondroFiller™ to support the repair environment. For most patients, the consultation-to-injection pathway moves within a matter of weeks rather than months.

The guide cost for the injection is £2,995; confirm at the point of enquiry exactly what is included and whether any additional elements apply to your protocol. There is no requirement for a GP referral.

Lincolnshire Hip is part of the MSK Doctors group and accepts patients without referral for hip assessment.