Evidence base

Ahmed I, Khatri C, Spalding T, Smith N. Meniscal allograft transplantation in patients with substantial cartilage disease led to a sustained long-term improvement in patient-reported outcome measures. Knee Surg Sports Traumatol Arthrosc. 2025 Aug;33(8):2771-2780. doi: 10.1002/ksa.12536. Epub 2024 Nov 7. PMID: 39506549.

Key points

• Meniscal transplantation improves pain and function for up to 10 years
• Patients with cartilage damage improve as much as those without
• Around 8 out of 10 transplants are still functioning long term in patients with cartilage damage
• Around 9 out of 10 are functioning in patients without cartilage damage
• Patients with cartilage damage have a higher risk of further surgery
• Earlier treatment may lead to better long-term outcomes

Why is this important?

Traditionally, meniscal transplantation has been recommended for patients with relatively healthy cartilage.

However, many patients present later, once cartilage damage has already developed. These patients often:

• are too young for knee replacement
• may not be suitable for osteotomy
• have limited treatment options

This study helps answer whether meniscal transplantation is still beneficial in this more complex group.

What did the study involve?

We reviewed 422 patients who underwent meniscal transplantation:

• 281 patients had little or no cartilage damage
• 129 patients had full-thickness cartilage damage

Patients were followed for an average of just over 6 years, with outcomes measured for up to 10 years after surgery.

We assessed:

• pain and function using validated knee scores
• activity levels
• graft survival, meaning whether the transplant remained in place or required further surgery

What were the results?

Improvement in symptoms

Both groups improved significantly after surgery.

Patients with cartilage damage improved just as much as those without, and this improvement was maintained for up to 10 years.

As shown in the results (see graphs on page 8 of the paper), knee scores improved from around the low 40s before surgery to approximately 65 to 75 after surgery, with sustained benefit over time.

Graft survival

There was a difference in how long the transplant lasted:

• Approximately 94 percent of transplants were still functioning in patients without cartilage damage
• Approximately 81 percent were still functioning in patients with cartilage damage

This shows that the operation is still effective in patients with cartilage damage, although there is a higher chance of needing further surgery over time.

Complications

Patients with cartilage damage:

• were more likely to need additional procedures
• had a higher rate of further surgery related to the knee

This reflects the more advanced nature of their condition rather than a failure of the treatment itself.

What does this mean for you?

Meniscal transplantation can still be a very effective treatment even if there is already cartilage damage in the knee.

It can:

• improve pain and function in the long term
• help delay the need for knee replacement in younger patients

However:

• the risk of further surgery is higher
• outcomes are generally more predictable when surgery is performed earlier

Evidence base

Smith NA, Parsons N, Wright D, Hutchinson C, Metcalfe A, Thompson P, Costa ML, Spalding T. A pilot randomized trial of meniscal allograft transplantation versus personalized physiotherapy for patients with a symptomatic meniscal deficient knee compartment. Bone Joint J. 2018 Jan;100-B(1):56-63. doi: 10.1302/0301-620X.100B1.BJJ-2017-0918.R1. PMID: 29305451.

Key points

• Meniscal transplantation improves pain and function more than physiotherapy at one year
• The average improvement is around 10 to 20 points greater on validated knee scores
• Physiotherapy still provides benefit and remains an important treatment option
• Surgery carries higher risk and should be carefully considered
• Ongoing research will further define which patients benefit most

What does the evidence show?

We conducted one of the first studies directly comparing meniscal transplant surgery with specialist physiotherapy for patients who have ongoing pain after losing part or all of their meniscus.

Why is this important?

The meniscus is a key structure that helps distribute load across the knee. When it is lost, contact pressures increase, which can lead to pain, reduced function, and a higher risk of developing arthritis.

Meniscal transplantation aims to restore this function and improve symptoms. Until recently, there had been no direct comparison between surgery and high-quality non-surgical treatment.

What did the study involve?

We studied 36 patients with a symptomatic meniscus-deficient knee.

Patients either:

• were randomly allocated to meniscal transplant surgery or a structured physiotherapy programme, or
• chose their preferred treatment and were followed in the same way

Outcomes were assessed over 12 months using validated knee scores that measure pain, function, and quality of life.

What were the results?

At 12 months, patients who had meniscal transplantation improved more than those treated with physiotherapy.

• Overall knee score (KOOS4) improved by around 12 points more in the surgery group
• Pain improved by around 15 points more with surgery
• Function in daily activities improved by around 18 points more with surgery

These differences are considered clinically meaningful and suggest a real benefit from surgery in appropriately selected patients.

Other areas such as sport and quality of life also improved more after surgery, although these differences were smaller.

Patients treated with physiotherapy also improved, confirming that this remains a valuable treatment option.

Risks and considerations

Meniscal transplantation is a surgical procedure and carries some risks.

In this study:

• There were 5 complications in the surgery group
• There was 1 complication in the physiotherapy group

Most surgical complications were manageable, but this highlights the importance of careful patient selection.

Physiotherapy avoids surgical risk but may not provide the same level of improvement for all patients.

What does this mean for you?

Meniscal transplantation can provide meaningful improvements in pain and function, particularly in younger, active patients with ongoing symptoms after meniscus loss.

Physiotherapy remains an important first step and may be sufficient for some patients.

The right treatment depends on:

• your symptoms
• your activity goals
• the condition of your knee

Ongoing research

This study was designed as an early step to better understand the role of meniscal transplantation.

We are now leading a large national study, the METEOR 2 trial, which aims to provide more definitive answers by comparing meniscal transplantation with non-surgical treatment across multiple centres.

Evidence base

Ahmed I, Khatri C, Davidescu A, Spalding T, Smith N. Returning to competitive sport after meniscal allograft transplant is associated with sustained graft survival and improved patient-reported outcomes. Knee Surg Sports Traumatol Arthrosc. 2025 Oct 27. doi: 10.1002/ksa.70137. Epub ahead of print. PMID: 41144796.

Key points

• Returning to competitive sport after meniscal transplantation does not increase the risk of graft failure
• Around 94 percent of patients who returned to sport still had a functioning transplant at 5 years
• Outcomes were better in patients who returned to sport compared to those who did not
• Knee function scores were around 15 to 20 points higher in those returning to sport
• Patients can safely return to high-level sport once fully rehabilitated

Why is this important?

There has traditionally been concern about returning to sport after meniscal transplantation due to the risk of damaging the graft.

Previous expert opinion advised caution, particularly with high-impact and pivoting sports.

This study helps answer an important question for active patients: can you safely return to sport after surgery?

What did the study involve?

We analysed 422 patients who underwent meniscal transplantation:

• 51 patients returned to competitive sport
• 371 patients did not return to this level

Return to sport was defined as a high level of activity, including sports such as football, tennis, and basketball.

Patients were followed for up to 10 years, assessing:

• graft survival
• pain and function
• activity levels

What were the results?

Graft survival

Returning to sport did not increase the risk of failure.

• At 5 years, 94 percent of patients who returned to sport still had a functioning transplant
• This compared to around 89 percent in those who did not return to sport

As shown in the survival curve (page 5), early outcomes were actually slightly better in the return-to-sport group, with no long-term disadvantage.

Function and outcomes

Patients who returned to sport had consistently better outcomes at all time points.

For example:

• IKDC score at 10 years was around 80 in the return-to-sport group compared to around 61 in those who did not return
• Lysholm scores were around 10 to 15 points higher at all time points
• KOOS scores for pain, sport, and quality of life were also higher

These differences are clinically meaningful and reflect better overall knee function.

What do the graphs show?

The graphs (pages 6 to 8) demonstrate that:

• Patients who returned to sport achieved higher function early after surgery
• These improvements were maintained long term
• There was no drop-off in outcomes despite returning to high-level activity

What does this mean for you?

This study provides reassurance that returning to sport after meniscal transplantation is safe in appropriately selected patients.

In particular:

• Returning to high-level sport does not appear to damage the transplant
• Patients who return to sport often have better function and outcomes
• Restricting activity purely to protect the knee may not be necessary

Return to sport is typically considered at around 12 months after surgery, once strength, control, and function have been restored.

Key considerations

• Not all patients will be suitable for high-level sport
• A structured rehabilitation programme is essential
• Decisions should be individualised based on symptoms, goals, and knee condition

Evidence base

Ayuob A, Raj S, Jessup J, Searle HKC, Ahmed I, Thompson P, Shah F, Metcalfe A, Smith N. Introducing “Delta Angle” of Posterior Tibial Slope and Its Impact on ACL Reconstruction Failures: A Regression Analysis of 1174 Patients. Am J Sports Med. 2025 Aug;53(10):2387-2396. doi: 10.1177/03635465251355213. Epub 2025 Jul 21. PMID: 40690738.

This study was conducted by our team at University Hospitals Coventry and Warwickshire to better understand how the tibial slope, and difference on either side of the knee affect outcomes after ACL reconstruction

Key points

• A new measurement called the delta angle helps predict ACL reconstruction failure
• The delta angle reflects the difference between the inner and outer slopes of the tibia
• For every 1 degree increase in delta angle, the risk of ACL failure increases by around 70 percent
• A delta angle of around 6 degrees increases the risk of failure more than fivefold
• This may help identify patients who need additional procedures to protect the ACL graft

What is the delta angle?

The tibia (shin bone) is not flat at the top. It has a slope that influences how forces pass through the knee.

Traditionally, surgeons have looked at the overall slope. This study shows that the difference between the inner (medial) and outer (lateral) slope is more important.

This difference is called the delta angle.

• The medial slope is measured on the inner side of the knee
• The lateral slope is measured on the outer side
• The delta angle is the difference between the two

Why is this important?

ACL reconstruction can fail for a number of reasons. One of the key factors is the shape of the bone.

A steeper slope increases forward movement of the tibia. When there is also a difference between the inner and outer slopes, this creates additional rotational forces.

These combined forces increase strain on the ACL graft and can increase the risk of failure.

What did the study involve?

We analysed 1174 patients who had undergone ACL reconstruction.

Patients were grouped into:

• successful primary ACL reconstruction
• revision ACL reconstruction (failed graft)
• contralateral ACL injuries

We measured:

• medial slope
• lateral slope
• delta angle

We then assessed how these related to the risk of graft failure.

What were the results?

Differences in bone shape

Patients with failed ACL reconstructions had:

• Lower medial slope, around 3.6 degrees compared to 5.2 degrees
• Higher lateral slope, around 9.7 degrees compared to 8.3 degrees
• A significantly higher delta angle, around 6.2 degrees compared to 3.1 degrees

This shows that it is not just the slope itself, but the imbalance between the two sides that matters.

Risk of ACL failure

The delta angle was a strong predictor of failure:

• Each 1 degree increase increased the risk of revision surgery by around 70 percent
• A delta angle of 6 degrees increased the risk by approximately 5 times compared to a neutral knee.

This is one of the strongest anatomical risk factors identified for ACL failure.

What does this mean for you?

This study helps explain why some ACL reconstructions fail despite good surgery and rehabilitation.

In particular:

• Bone shape plays a major role in outcomes
• Patients with a high delta angle may be at higher risk
• Additional procedures, such as lateral extra-articular tenodesis or slope-correcting osteotomy, may be considered in selected cases

Key considerations

• Not all patients need additional surgery
• The delta angle is one of several factors considered when planning treatment
• This measurement may help personalise surgery and reduce the risk of failure

Evidence base

Searle HKC, Raj S, Ridha A, Ahmed I, Khatri C, Metcalfe A, Smith N. The recovery trajectory of people undergoing treatment for knee articular cartilage damage: A systematic review and meta-analysis. Knee. 2025 Oct;56:211-223. doi: 10.1016/j.knee.2025.05.031. Epub 2025 Jun 4. PMID: 40472679.

This study was conducted by our team at University Hospitals Coventry and Warwickshire to better understand how patients recover over time after different cartilage treatments.

Key points

• Most patients improve after cartilage treatment, regardless of the type of treatment
• The greatest improvement occurs in the first 12 to 24 months
• Improvements are generally maintained up to 5 years
• Microfracture may show a decline in outcomes after 2 to 3 years
• Cell-based treatments show more sustained long-term improvement
• This helps explain why different treatments often appear similar in studies

Why is this important?

Cartilage damage in the knee is common and can cause significant pain and limitation in activity.

There are several treatment options, including:

• physiotherapy
• microfracture
• scaffold-based repair
• cell-based therapies such as ACI

Patients often ask which treatment is best. This study, carried out by our research group, helps answer a slightly different but important question: how do patients recover over time?

What did the study involve?

This was a systematic review of prospective studies, meaning it analysed multiple high-quality studies over time.

It included patients treated with:

• non-operative treatment
• microfracture
• scaffold-based repair
• cell-based cartilage repair

Outcomes such as pain, function, and activity levels were tracked over time using validated scores including IKDC, KOOS, and Lysholm.

What does recovery look like?

Across all treatments, a consistent pattern was seen:

• Rapid improvement in the first 6 to 12 months
• Continued improvement up to around 24 months
• A plateau phase after this, with stable outcomes

This pattern was consistent across the studies analysed by our team.

Differences between treatments

Microfracture

• Improves symptoms early
• Often plateaus by 12 months
• Some patients experience worsening symptoms after 2 to 3 years
• In some cases, pain can return towards baseline by 3 years

Scaffold-based repair

• Shows steady improvement over time
• Outcomes appear better than microfracture
• Limited long-term data beyond 3 years

Cell-based therapies (e.g. ACI)

• Larger improvements in function and symptoms
• Improvement continues up to around 24 months
• Results are maintained up to 5 years

Non-operative treatment

• Also leads to improvement over time
• May be suitable for some patients, particularly with lower demands

What does this mean for you?

The key message from this study is that most patients improve over time, regardless of treatment.

This is important because:

• It explains why many studies show similar outcomes between treatments
• It highlights the importance of patience during recovery
• It supports shared decision-making based on individual goals

For higher-demand patients or larger defects:

• More advanced treatments may provide more sustained improvement

Key considerations

• Recovery after cartilage treatment takes time, often up to 1 to 2 years
• Early improvement is common, but long-term durability varies by treatment
• Microfracture may not provide lasting results in some patients
• Treatment choice should be individualised based on symptoms, goals, and lesion characteristics

Evidence base

Ridha A, Raj S, Searle H, Ahmed I, Smith N, Metcalfe A, Khatri C. The recovery trajectory of anterior cruciate ligament ruptures in randomised controlled trials: A systematic review and meta-analysis of operative and nonoperative treatments. Knee Surg Sports Traumatol Arthrosc. 2025.
https://doi.org/10.1002/ksa.12626

This study was conducted by our team to better understand how patients recover over time after ACL injury, with or without surgery.

Key points

• Both surgery and rehabilitation lead to significant improvement after ACL injury
• Most recovery occurs in the first 6 to 12 months
• Improvements continue up to around 2 years before plateauing
• Some patients can achieve excellent outcomes without surgery
• Surgery remains important for those with instability or high sporting demands

Why is this important?

An ACL rupture is a common knee injury, particularly in active individuals.

Traditionally, surgery has been considered the standard treatment. However, many patients can also do well with structured rehabilitation alone.

This study, performed by our research group, helps clarify how recovery progresses over time and whether surgery changes that trajectory.

What did the study involve?

This was a systematic review and meta-analysis of randomised controlled trials.

It included:

• patients treated with ACL reconstruction
• patients treated with structured rehabilitation

Outcomes such as pain, function, and activity level were measured using validated scores across multiple time points.

By combining data from several trials, the study provides a clearer picture of recovery patterns.

What does recovery look like?

The overall recovery pattern was similar in both groups:

• Rapid improvement in the first 6 months
• Continued gains up to 12 to 24 months
• A plateau phase after this

This suggests that the body has a strong natural recovery capacity following ACL injury, supported by rehabilitation.

Surgery vs non-operative treatment

ACL reconstruction

• Provides mechanical stability to the knee
• May be beneficial for patients returning to pivoting or high-demand sport
• Follows a similar recovery trajectory to rehabilitation

Rehabilitation alone

• Can lead to excellent functional outcomes in selected patients
• Avoids the risks associated with surgery
• Requires commitment to structured physiotherapy

What does this mean for you?

The key message from this study is that both treatment options can be effective.

The decision between surgery and rehabilitation should be based on:

• your activity level and sporting goals
• symptoms of instability
• associated injuries
• personal preference

For some patients, rehabilitation alone is sufficient.
For others, particularly those returning to high-level sport, surgery may be the better option.

Key considerations

• Recovery after ACL injury takes time, often 9 to 12 months or longer
• Early improvement is expected, but full recovery continues beyond a year
• Not all patients require surgery
• Treatment should be tailored to the individual

Evidence base

Dagneaux L, Bourlez J, Degeorge B, Canovas F. Return to sport after total or unicompartmental knee arthroplasty: an informative guide. EFORT Open Rev. 2017.

This review summarises the current evidence on returning to sport after knee replacement, including both total knee replacement (TKR) and partial knee replacement (UKR).

Key points

• Most patients can return to sport after knee replacement
• Low-impact activities are safe and recommended
• Return to sport usually begins between 3 and 6 months
• Partial knee replacement (UKR) has higher return-to-sport rates than total knee replacement (TKR)
• High-impact sports are generally discouraged
• Recovery and return depend on patient factors such as age, fitness, and motivation

Why is this important?

Many patients considering knee replacement want to know whether they can stay active afterwards.

Traditionally, surgeons advised avoiding sport. However, more recent evidence suggests that returning to activity is not only possible, but beneficial for overall health and quality of life.

What does recovery look like?

Recovery follows a gradual progression:

• First 3 months: focus on regaining movement, strength, and balance
• 3 to 6 months: return to light sporting activity
• Beyond 6 months: progression to more demanding activities depending on confidence and function

Return to sport should always be gradual and guided by your surgeon and physiotherapist.

Total vs partial knee replacement

Partial knee replacement (UKR)

• Higher return-to-sport rates, up to around 75% to 100%
• Faster recovery, often by around 3 months
• Better functional performance in sport

Total knee replacement (TKR)

• Return-to-sport rates vary widely, around 36% to 89%
• Slightly slower recovery
• Excellent outcomes for pain relief and daily function

Which sports are recommended?

Sports are generally grouped into three categories:

Recommended (low impact)

• Walking
• Cycling
• Swimming
• Golf

These are encouraged for all patients.

Allowed with experience (moderate impact)

• Hiking
• Skiing
• Doubles tennis
• Gym-based exercise

These may be appropriate if you have previous experience and good control.

Generally discouraged (high impact)

• Running
• Football
• Basketball
• Singles tennis

These place higher stress on the implant and may increase the risk of wear over time.

What affects your return to sport?

Several factors influence recovery:

• Age: younger patients often return more easily
• Pre-injury activity level: active patients are more likely to return
• Motivation: a key driver of recovery
• Weight: higher body weight may affect outcomes
• Rehabilitation: structured physiotherapy is essential

What does this mean for you?

Most patients can return to an active lifestyle after knee replacement.

Key things to understand:

• Activity is encouraged and beneficial for overall health
• Low-impact sport is safe and recommended
• Higher-impact sport may be possible in selected cases, but should be approached with caution

The goal of knee replacement is not just pain relief, but helping you return to an active and enjoyable lifestyle.

Key considerations

• Return to sport typically starts at 3 to 6 months
• Full recovery continues beyond this
• Activity should be built up gradually
• Treatment and advice should be tailored to your goals and lifestyle

ACL SNNAP Trial (Beard et al., 2022)

Rehabilitation versus ACL Reconstruction for Persistent Instability

Beard DJ, Davies L, Cook JA, Stokes J, Leal J, Fletcher H, Abram S, Chegwin K, Greshon A, Jackson W, Bottomley N, Dodd M, Bourke H, Shirkey BA, Paez A, Lamb SE, Barker K, Phillips M, Brown M, Lythe V, Mirza B, Carr A, Monk P, Morgado Areia C, O’Leary S, Haddad F, Wilson C, Price A; ACL SNNAP Study Group. Rehabilitation versus surgical reconstruction for non-acute anterior cruciate ligament injury (ACL SNNAP): a pragmatic randomised controlled trial. Lancet. 2022 Aug 20;400(10352):605-615. doi: 10.1016/S0140-6736(22)01424-6. PMID: 35988569.

Key Points

• This large UK randomised controlled trial compared surgery versus physiotherapy for ACL injuries that had not settled over time
• Patients who had ACL reconstruction had better outcomes at 18 months
• Surgery improved knee function by around 8 points more on a validated outcome score
• Around 30% of patients initially treated with physiotherapy eventually required surgery
• Complication rates were low and similar between both groups
• Surgery was also found to be cost-effective in the NHS setting

What was studied?

This was a high-quality multicentre trial involving 316 patients across 29 NHS hospitals in the UK

All patients had:

• An ACL injury that was no longer acute
• Ongoing symptoms such as instability or the knee “giving way”

They were randomly assigned to:

• ACL reconstruction surgery
• Structured rehabilitation (physiotherapy), with surgery later if needed

What were the results?

Overall improvement

Both groups improved, but surgery gave better outcomes:

• Surgery group improved from ~46 to 73
• Rehabilitation group improved from ~43 to 65

This represents:

• An average advantage of 7.9 points for surgery
• A statistically and clinically meaningful difference

Need for later surgery

A key finding was how many patients needed delayed surgery:

• 31% of patients in the physiotherapy group went on to have ACL reconstruction
• Patients who eventually had surgery ended up with similar outcomes to those who had early surgery, but took longer to improve

This highlights that:

• Physiotherapy alone works well for some patients
• But many will still require surgery to restore stability

Symptoms, function, and activity

Across multiple measures, surgery performed better:

• Less pain
• Better knee function
• Higher activity levels
• Better quality of life scores

Patient satisfaction was also higher:

• 83% of surgical patients felt their knee was better
• Compared to 68% in the rehabilitation group

Return to sport

Return to pre-injury sport was limited in both groups:

• 28% after surgery
• 24% after rehabilitation

This reflects the challenging nature of ACL injuries, regardless of treatment

Safety and cost

• Complication rates were low and similar between groups
• Surgery was more expensive upfront but considered cost-effective overall
• There were no major safety concerns identified

What does this mean for patients?

For patients with ongoing instability after an ACL injury:

• ACL reconstruction is more likely to restore stability and function
• Physiotherapy is still a valid first approach, particularly for less demanding activity levels
• However, many patients may ultimately need surgery

The decision should be individual, based on:

• Activity level and sporting goals
• Degree of instability
• Personal preferences

Lateral Extra-articular Tenodesis (LET) in ACL Reconstruction

 https://pubmed.ncbi.nlm.nih.gov/31940222/

Getgood AMJ, et al. Lateral Extra-articular Tenodesis Reduces Failure of Hamstring Tendon Autograft Anterior Cruciate Ligament Reconstruction: 2-Year Outcomes From the STABILITY Study Randomized Clinical Trial. Am J Sports Med. 2020 Feb;48(2):285-297. doi: 10.1177/0363546519896333. Epub 2020 Jan 15. PMID: 31940222.

Key Points

• This large randomised controlled trial looked at whether adding a lateral extra-articular tenodesis (LET) improves ACL reconstruction outcomes
• Adding LET significantly reduced graft failure rates
• Failure rates were reduced from around 11% to 4% at 2 years
• The benefit was greatest in younger, higher-risk patients
• Knee stability was improved without a meaningful increase in complications
• University Hospitals Coventry and Warwickshire (UHCW) contributed to this international trial as one of only two UK centres

What was studied?

This was a large multicentre randomised controlled trial involving over 600 patients.

All patients had:

• ACL reconstruction using a hamstring tendon graft

They were randomly assigned to:

• Standard ACL reconstruction
• ACL reconstruction plus lateral extra-articular tenodesis (LET)

LET is an additional procedure performed on the outside of the knee to improve rotational stability.

UHCW was one of only two UK centres contributing patients to this important international study.

What were the results?

Graft failure

Adding LET significantly reduced failure:

• ACL reconstruction alone: ~11% failure rate
• ACL + LET: ~4% failure rate

This represents:

• A relative reduction in failure of around 60–65%
• One of the most important findings in modern ACL surgery

Rotational stability

Patients who had LET:

• Had better control of rotational instability
• Were less likely to experience the knee “giving way”

This is particularly important for:

• Cutting and pivoting sports (e.g. football, rugby, skiing)

Patient-reported outcomes

• Both groups improved significantly
• Overall patient-reported scores were similar between groups
• The key difference was reduced failure risk rather than symptom scores

Complications and safety

• No significant increase in major complications
• Slight increase in early post-operative pain reported in LET group
• No clear long-term downside identified

Who benefits most?

The benefit of LET was greatest in higher-risk patients, including:

• Younger patients
• Those returning to pivoting sports
• Patients with high-grade rotational instability
• Revision ACL case

What does this mean for patients?

For patients undergoing ACL reconstruction:

• Standard ACL reconstruction works well for many patients
• Adding LET can significantly reduce the risk of graft failure
• This is particularly important in active or high-risk individuals

Treatment should be tailored based on:

• Activity level
• Sporting demands
• Individual risk of re-injury

How this relates to my practice

This study has been highly influential in modern ACL surgery.

Having contributed to this trial through UHCW, I incorporate its findings into clinical decision-making, particularly when assessing patients at higher risk of graft failure.

In selected patients, adding LET can:

• Improve rotational stability
• Reduce the risk of re-injury
• Support a safer return to sport

Total vs Partial Knee Replacement for Medial Knee Arthritis

 Beard DJ, et al. The clinical and cost-effectiveness of total versus partial knee replacement in patients with medial compartment osteoarthritis (TOPKAT): 5-year outcomes of a randomised controlled trial. Lancet. 2019 Aug 31;394(10200):746-756. doi: 10.1016/S0140-6736(19)31281-4. Epub 2019 Jul 17. PMID: 31326135; PMCID: PMC6727069.

Key Points

• This large UK randomised controlled trial compared total knee replacement (TKR) with partial knee replacement (PKR)
• Both operations led to major improvements in pain and function
• There was no meaningful difference in overall outcomes at 5 years
• Partial knee replacement was more cost-effective and had slightly better patient-reported outcomes
• Complication rates were lower with partial knee replacement
• This is the highest-quality evidence guiding the choice between these two operations

What was studied?

This was a large multicentre UK randomised controlled trial involving:

• 528 patients across 27 centres
• Patients with arthritis affecting only the inner (medial) part of the knee

Patients were randomly assigned to:

• Total knee replacement (replacing the whole joint)
• Partial knee replacement (replacing only the damaged compartment)

The main outcome measured was the Oxford Knee Score (OKS) at 5 years.

What were the results?

Improvement in pain and function

Both groups improved significantly:

• Average improvement of more than 18 points on the Oxford Knee Score
• This represents a large and meaningful improvement in symptoms

At 5 years:

• PKR: mean OKS ~38
• TKR: mean OKS ~37
• Difference: not statistically or clinically significant

Patient experience

Patients undergoing partial knee replacement reported:

• Slightly better perception of improvement
• Higher likelihood of saying their knee felt better than before surgery
• Greater likelihood of choosing the operation again

For example:

• 95% of PKR patients felt their knee was better vs 90% in TKR
• 91% would choose surgery again vs 84% in TKR

Complications and re-operations

• Complications were lower with partial knee replacement (20% vs 27%)
• Rates of re-operation and revision were similar between groups

This is important as registry data had previously suggested higher revision rates for partial knee replacement, which was not seen in this trial

Recovery and hospital stay

• Shorter hospital stay with partial knee replacement
  • PKR: ~3.2 days
  • TKR: ~4.3 days

Cost-effectiveness

Partial knee replacement was:

• Less expensive (around £900 cheaper per patient)
• More effective overall in quality-adjusted life years
• Probability of being the most cost-effective option: >99%

Why is this important?

This is the largest and most robust randomised trial comparing partial and total knee replacement.

It showed that:

• Both operations work very well
• Partial knee replacement offers similar outcomes with some advantages
• Real-world registry data may overestimate revision risk in partial knee replacement

What does this mean for patients?

For patients with arthritis affecting only one part of the knee:

• Both total and partial knee replacement are excellent options
• Partial knee replacement may offer:
  • Faster recovery
  • More natural knee feeling
  • Lower complication rates
  • Lower overall cost

However:

• Not all patients are suitable for partial knee replacement
• Surgical expertise and correct patient selection are key

How this relates to my practice

This study was led by Professor David Beard, with whom I collaborate on research, and forms a key part of the evidence base guiding knee replacement decisions in the UK.

In my practice, I use these findings to:

• Carefully assess whether a patient is suitable for partial knee replacement
• Offer personalised treatment based on anatomy, symptoms, and activity level
• Ensure patients understand the benefits and limitations of each option