Jonathan Ming Ren French

Jonathan Ming Ren French

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

The organizations/institutes from the scholar's latest article


Jonathan Ming Ren French has a total of 65 co-authors. Here are the top co-authors by number of shared publications:

  • Michael Richard Whitehouse

    Bristol Medical School, University of Bristol, Bristol, UK

    4 shared publications
  • Adrian Sayers

    Musculoskeletal Research Unit, Translational Health Sciences, Bristol Medical School, University of Bristol, Southmead Hospital, Bristol, United Kingdom

    3 shared publications
  • Ashley W. Blom

    Musculoskeletal Research Unit, Translational Health Sciences, Bristol Medical School, University of Bristol, Southmead Hospital, Bristol, United Kingdom

    2 shared publications
  • Erik Lenguerrand

    Musculoskeletal Research Unit, Translational Health Sciences, Bristol Medical School, University of Bristol, Southmead Hospital, Bristol, United Kingdom

    2 shared publications
  • Kevin Deere

    Musculoskeletal Research Unit, Translational Health Sciences, Bristol Medical School, University of Bristol, Southmead Hospital, Bristol, United Kingdom

    2 shared publications
  • Kevin Deere

    Musculoskeletal Research Unit, Learning and Research Building, Southmead Hospital, University of Bristol Medical School, Bristol, UK

    2 shared publications

Latest Publications

  • Open Access

    National survey of protocols for day-case hip and knee arthroplasty in the UK

    by Tomos A. Edwards, Jamie Large, Jonathan M. R. French, Jonathan T. Evans, Mike R. Reed, Michael R. Whitehouse

    Aims: Day-case joint arthroplasty, where patients are discharged on the day of surgery, is increasingly used to meet rising demand in a resource-efficient manner. NHS England guidance states that all patients should be placed on an ambulatory pathway (zero to one night stay). However, little is known about the prevalence, structure, and implementation of day-case protocols across the UK. Methods: An online survey was sent to all NHS institutions performing hip or knee arthroplasty. Respondents reported the presence of day-case, ambulatory (zero to one night stay), or generic enhanced recovery protocols. Data were collected across 21 questions covering key perioperative domains and analyzed descriptively, and model health system data was used to assess length of stay (LoS). Results: Overall, 63 responses were received covering 86 hospitals (56 trusts), of which 78 (91%) perform day-case surgery. In total, 41 (48%) had a dedicated day-case protocol, 23 (27%) had ambulatory protocols, and 15 (17%) used generic enhanced recovery pathways. Only 22% of hospitals with a day-case pathway placed all patients on it by default. Protocol content showed substantial variation, including the use of sedation as part of anaesthesia (49%), presence of therapy services beyond 17:00 (59%), and nurses competent in assessing day zero mobility (56%). One third of hospitals had no mechanism for patients to contact out-of-hours support. LoS was shorter in hospitals using day-case or ambulatory protocols when compared with those that did not, however, this did not reach statistical significance. Conclusion: While day-case joint arthroplasty is widely performed in the NHS, dedicated protocols are used in fewer than half of hospitals, and considerable variation exists. These results can be used collaboratively by hospitals that are trying to establish pathways, and to guide further research aiming to identify best practice and provide standardization for day-case protocols. Cite this article: Bone Jt Open 2026;7(5):651–658.

  • Open Access

    Social inequalities in patient outcomes after total hip replacement surgery for osteoarthritis in England: A population-based cohort study of the National Joint Registry

    by Rita Patel, Erik Lenguerrand, Yoav Ben-Shlomo, Jonathan French, Amar Rangan, Robin Brittain, Kevin Deere, Adrian Sayers, Ashley W. Blom, Michael R. Whitehouse, et al.

    Background: Reducing health inequalities is of national importance. Total hip replacement (THR) is a commonly used elective surgical procedure. Few studies have examined area-level inequalities for a wide range of outcomes following THR. The aim of this study is to compare area-level socioeconomic differences in outcomes following primary THR surgery for osteoarthritis in England. Methods and findings: This is a population-based prospective cohort study of the National Joint Registry (NJR). Data from the NJR were linked to national mortality, Hospital Episode Statistics and Patient Reported Outcome Measures (PROMs) databases for England from 2007 to 2017 with follow-up to 2023 for outcomes, for patients aged 50 years and over with osteoarthritis. Outcomes of 90-day mortality; 5-year revision rate; 6-month health complications; 1-year rehospitalisation and reoperation for orthopaedic indications; and patient-reported Oxford Hip Score (OHS), post-THR surgery were examined by area-level Index of Multiple Deprivation quintiles. Modified Poisson regression was adjusted for patient age, sex, body mass index, pre-operative physical state and comorbidity. Among 448,184 patients with primary THR, mean age was 70 years (standard deviation: 9 years) and 61% were women. Patients from the most deprived group were more likely to die within 90 days of the operation compared to the least deprived group (adjusted rate ratio, RR: 1.25 (95% confidence interval (CI) [1.07, 1.46]); adjusted risk difference, RD: 9 (95% CI [2, 16]) per 10,000. Similarly, those from the most deprived group were more likely to experience complications (RR: 1.26 (95% CI [1.21, 1.32]); RD: 1.14% (95% CI [0.92, 1.36])); be rehospitalised (RR: 1.16 (95% CI [1.14, 1.19]; RD: 2.78% (95% CI [2.39, 3.17])) or reoperated (RR: 1.23 (95% CI [1.13, 1.33]); RD: 0.31% (95% CI [0.19, 0.44])) and report poorer OHS (adjusted score: −2.97 (95% CI [−3.10, −2.84]) N = 200,522). There was no variation by deprivation level for THR revision rates at 5 years (RR: 1.02 (95% CI [0.94, 1.10]); RD: 0.02% (95% CI [−0.10, 0.15])). The main study limitations are the lack of complete PROMs data, and the exclusion of self-funded patients or those with private insurance for THR procedures in independent hospitals. Conclusions: Inequalities in several outcomes after THR are present in England by area-level deprivation. These findings are useful to inform shared decision-making for patients deciding whether to undergo hip replacement and to benchmark the effectiveness of policies which aim to reduce health inequalities following THR.


  • Day-case knee and hip replacement

    by Jonathan M. R. French, Amy Woods, Adrian Sayers, Kevin Deere, Michael R. Whitehouse

    Aims: Day-case knee and hip replacement, in which patients are discharged on the day of surgery, has been gaining popularity during the last two decades, and particularly since the COVID-19 pandemic. This systematic review presents the evidence comparing day-case to inpatient-stay surgery.Methods: A systematic literature search was performed of MEDLINE, Embase, and grey literature databases to include all studies which compare day-case with inpatient knee and hip replacement. Meta-analyses were performed where appropriate using a random effects model. The protocol was registered prospectively (PROSPERO CRD42023392811).Results: A total of 38 studies were included, with a total of 83,888 day-case procedures. The studies were predominantly from the USA and Canada, observational, and with a high risk of bias. Day-case patients were a mean of 2.08 years younger (95% CI 1.05 to 3.12), were more likely to be male (odds ratio (OR) 1.3 (95% CI 1.19 to 1.41)), and had a lower mean BMI and American Society of Anesthesiologists grades compared with inpatients. Overall, day-case surgery was associated with significantly lower odds of readmission (OR 0.83 (95% CI 0.73 to 0.96); p = 0.009), subsequent emergency department attendance (OR 0.62 (95% CI 0.48 to 0.79); p < 0.001), and complications (OR 0.7 (95% CI 0.55 to 0.89) p = 0.004), than inpatient surgery. There were no significant differences in the rates of reoperation or mortality. The overall rate of successful same-day discharge for day-case surgery was 85% (95% CI 81 to 88). Patient-reported outcome measures and cost-effectiveness were either equal or favoured day-case.Conclusion: Within the limitations of the literature, in particular the substantial risk of selection bias, the outcomes following day-case knee and hip replacement appear not to be inferior to those following an inpatient stay. The evidence is more robust for unicompartmental knee replacement (UKR) than for total knee replacement (TKR) or total hip replacement (THR). The rate of successful same-day discharge is highest in UKR, followed by TKR and comparatively lower in THR.Cite this article: Bone Joint J 2024;106-B(12):1385–1392.


  • Open Access

    The completeness of national hip and knee replacement registers

    by Jonathan M R French, Kevin Deere, Michael R Whitehouse, Derek J Pegg, Enrico Ciminello, Riccardo Valentini, Marina Torre, Keijo Mäkelä, Anne Lübbeke, Eric R Bohm, et al.

    Background and purpose: National joint replacement registries were developed for prospective monitoring of outcomes and post-market surveillance of implants. Increasingly registry data informs practice. However, analysis of a registry can only be as good as the data it captures on the population of interest. We aimed to analyze completeness of reporting of hip and knee replacement procedures for all national registries worldwide.Methods: We analyzed annual reports and data provided following written requests to all active national hip and knee replacement registries. Coverage was defined as the proportion of hospitals in the country that participate in the registry. Procedure completeness was defined as the proportion of procedures successfully captured by the registry.Results: 14 national registries were included, spanning years 2004 to 2022. Coverage was complete in 10. Median procedure completeness for primary hip and knee replacement across all years was 96.5% (interquartile range [IQR] 94.0–97.7%). Median procedure completeness for revisions was 88.5% (IQR 81.0–92.5%). The terminology used and method of calculation of completeness estimates in the registries were variable.Conclusion: National hip and knee replacement registry data generally reflects excellent coverage (full in 10 of 14 registries) and completeness (primary procedures 96.5% and revisions 88.5%) over the last 2 decades.


  • Open Access

    The association of bearing surface materials with the risk of revision following primary total hip replacement: A cohort analysis of 1,026,481 hip replacements from the National Joint Registry

    by Michael R. Whitehouse, Rita Patel, Jonathan M. R. French, Andrew D. Beswick, Patricia Navvuga, Elsa M. R. Marques, Ashley W. Blom, Erik Lenguerrand

    Background: The risk of re-operation, otherwise known as revision, following primary hip replacement depends in part on the prosthesis implant materials used. Current performance evidences are based on a broad categorisation grouping together different materials with potentially varying revision risks. We investigated the revision rate of primary total hip replacement (THR) reported in the National Joint Registry by specific types of bearing surfaces used. Methods and findings: We analysed THR procedures across all orthopaedic units in England and Wales. All patients who received a primary THR between 2003 and 2019 in the public and private sectors were included. We investigated the all-cause and indication-specific risks of revision using flexible parametric survival analyses to estimate adjusted hazard ratios (HRs). We identified primary THRs with heads and monobloc cups or modular acetabular component THRs with head and shell/liner combinations. A total of 1,026,481 primary THRs were analysed (Monobloc: n = 378,979 and Modular: n = 647,502) with 20,869 (2%) of these primary THRs subsequently undergoing a revision episode (Monobloc: n = 7,381 and Modular: n = 13,488). For monobloc implants, compared to implants with a cobalt chrome head and highly crosslinked polyethylene (HCLPE) cup, the all-cause risk of revision for monobloc acetabular implant was higher for patients with cobalt chrome (hazard rate at 10 years after surgery: 1.28 95% confidence intervals [1.10, 1.48]) or stainless steel head (1.18 [1.02, 1.36]) and non-HCLPE cup. The risk of revision was lower for patients with a delta ceramic head and HCLPE cup implant, at any postoperative period (1.18 [1.02, 1.36]). For modular implants, compared to patients with a cobalt chrome head and HCLPE liner primary THR, the all-cause risk of revision for modular acetabular implant varied non-constantly. THRs with a delta ceramic (0.79 [0.73, 0.85]) or oxidised zirconium (0.65 [0.55, 0.77]) head and HCLPE liner had a lower risk of revision throughout the entire postoperative period. Similar results were found when investigating the indication-specific risks of revision for both the monobloc and modular acetabular implants. While this large, nonselective analysis is the first to adjust for numerous characteristics collected in the registry, residual confounding cannot be rule out. Conclusions: Prosthesis revision is influenced by the prosthesis materials used in the primary procedure with the lowest risk for implants with delta ceramic or oxidised zirconium head and an HCLPE liner/cup. Further work is required to determine the association of implant bearing materials with the risk of rehospitalisation, re-operation other than revision, mortality, and the cost-effectiveness of these materials.


  • An analysis of the effect of the COVID-19-induced joint replacement deficit in England, Wales, and Northern Ireland suggests recovery will be protracted

    by Jonathan M. R. French, Kevin Deere, Tim Jones, Derek J. Pegg, Mike R. Reed, Michael R. Whitehouse, Adrian Sayers

    Aims: The COVID-19 pandemic has disrupted the provision of arthroplasty services in England, Wales, and Northern Ireland. This study aimed to quantify the backlog, analyze national trends, and predict time to recovery.Methods: We performed an analysis of the mandatory prospective national registry of all independent and publicly funded hip, knee, shoulder, elbow, and ankle replacements in England, Wales, and Northern Ireland between January 2019 and December 2022 inclusive, totalling 729,642 operations. The deficit was calculated per year compared to a continuation of 2019 volume. Total deficit of cases between 2020 to 2022 was expressed as a percentage of 2019 volume. Sub-analyses were performed based on procedure type, country, and unit sector.Results: Between January 2020 and December 2022, there was a deficit of 158,994 joint replacements. This is equivalent to over two-thirds of a year of normal expected operating activity (71.6%). There were 104,724 (-47.1%) fewer performed in 2020, 41,928 (-18.9%) fewer performed in 2021, and 12,342 (-5.6%) fewer performed in 2022, respectively, than in 2019. Independent-sector procedures increased to make it the predominant arthroplasty provider (53% in 2022). NHS activity was 73.2% of 2019 levels, while independent activity increased to 126.8%. Wales (-136.3%) and Northern Ireland (-121.3%) recorded deficits of more than a year’s worth of procedures, substantially more than England (-66.7%). It would take until 2031 to eliminate this deficit with an immediate expansion of capacity over 2019 levels by 10%.Conclusion: The arthroplasty deficit following the COVID-19 pandemic is now equivalent to over two-thirds of a year of normal operating activity, and continues to increase. Patients awaiting different types of arthroplasty, in each country, have been affected disproportionately. A rapid and significant expansion in services is required to address the deficit, and will still take many years to rectify.Cite this article: Bone Joint J 2024;106-B(8):834–841.


  • Open Access

    Computer Hexapod-assisted Orthopaedic Surgery for the Correction of Multiplanar Deformities throughout the Lower Limb

    by Jonathan Ming Ren French, Joshua Filer, Kathryn Hogan, James William Alexander Fletcher, Stephen Mitchell

    Computerised hexapod-assisted orthopaedic surgery (CHAOS) is a method by which complex multiplanar, multilevel deformity can be corrected with a high degree of accuracy utilising minimally invasive techniques within a single operative event. This study's aim was to report the reliability, accuracy and magnitude of correction achieved, alongside patient-reported outcomes and risk factors for complications when using the CHAOS technique throughout the lower limb. Retrospective review of medical records and radiographs for consecutive patients who underwent CHAOS for lower limb deformity correction at a tertiary centre between 2012 and 2020. There were 70 cases in 56 patients, with the site of surgery being the femur in 48 cases, proximal tibia in 17 and distal tibia in 5 cases. Multiplanar correction was performed in 43 cases, and multilevel osteotomy was undertaken in 23 cases. Fixation was undertaken with intramedullary nailing (IMN) in 49 cases and locked plates in 21. The maximum corrections were 40° rotation, 20° coronal angulation, 51° sagittal angulation and 62-mm mechanical axis deviation (MAD). Deformity correction was mechanically satisfactory in all patients bar one who was undercorrected requiring revision. The mean patient global impression of change (PGIC) score was 6.2 out of 7. Overall complication rate was 12/70 (17%). Complications from femoral surgery included two nonunions, one case of undercorrection, one case of stiffness, one muscle hernia and one pulmonary embolism. Complications from tibial surgery were one compartment syndrome, one pseudoaneurysm of the anterior tibial artery requiring stenting, one transient neurapraxia of the common peroneal nerve, one locking plate fatigue failure, one seroma and one superficial wound infection. Computerised hexapod-assisted orthopaedic surgery can be used for accurate correction of complex multilevel and multiplanar deformities of both the femur and tibia. The risk profile appears to differ between femoral and tibial surgeries, and also to that of traditional circular frame correction. Patients remain highly satisfied with both the functional and symptomatic outcomes. French JMR, Filer J, Hogan K, et al. Computer Hexapod-assisted Orthopaedic Surgery for the Correction of Multiplanar Deformities throughout the Lower Limb. Strategies Trauma Limb Reconstr 2024;19(1):9–14.


  • Open Access

    International Survey of Practice for Prophylactic Systemic Antibiotic Therapy in Hip and Knee Arthroplasty

    by Thomas Parsons, Jonathan French, Takeshi Oshima, Francisco Figueroa, Thomas Neri, Antonio Klasan, Sven Putnis

    (1) Background: Prophylactic systemic antibiotics are acknowledged to be an important part of mitigating prosthetic joint infections. Controversy persists regarding optimal antibiotic regimes. We sought to evaluate current international antibiotics guidelines for total joint arthroplasty (TJA) of the hip and knee. (2) Methods: 42 arthroplasty societies across 6 continents were contacted and their published literature reviewed. (3) Results: 17 societies had guidelines; of which 11 recommended an antibiotic agent or antibiotic class (10—cephalosporin; 1—cloxacillin); 15 recommended antibiotic infusion within an hour of incision and 10 advised for post-operative doses (8—up to 24 h; 1—up to 36 h; 1—up to 48 h). (4) Conclusions: Prophylactic antibiotic guidelines for TJA are often absent or heterogenous in their advice.


  • Distal biceps repair through a single incision with the use of a knotless cortical button device: Mid-term results

    by Angelos Assiotis, Jonathan French, Gray Edwards, Philip A McCann, Naomi Chalk, Rouin Amirfeyz

    Background: Distal biceps rupture presents with an increasing incidence and evidence suggests that although a surgical repair is not mandatory, it results in superior functional outcomes when compared to non-operative management. As implant technology has advanced, several devices have been utilised and studied in managing this pathology. We present our single-centre experience with the use of the ToggleLoc Ziploop reattachment device, a knotless cortical button implant, using a single-incision technique. Methods: Retrospective series of 70 consecutive distal biceps tendon repairs, at a mean follow-up of 45.6 months after surgery, using a standardised single implant, single-incision technique, and post-operative rehabilitation programme. Results: There was one (1.4%) re-rupture in our patient cohort. The range of motion was complete in all patients except for one patient who had symptomatic heterotopic ossification, causing limitation in pronation. Complications were minor with the commonest being transient neuropraxia of the lateral cutaneous nerve of the forearm. The mean Oxford elbow score was 46.9 out of 48, and the patient global impression of change scale was 7 out of 7 in 77% of cases. Conclusion: Our data support this technique and implant combination when dealing with acute and chronic distal biceps tendon rupture.


  • Open Access

    Adverse reaction to metal debris due to fretting corrosion between the acetabular components of modular dual-mobility constructs in total hip replacement: a systematic review and meta-analysis

    by Jonathan M. R. French, Paul Bramley, Sean Scattergood, Nemandra A. Sandiford

    Modular dual-mobility (MDM) constructs can be used to reduce dislocation rates after total hip replacement (THR). However, there are concerns about adverse reaction to metal debris (ARMD) as a result of fretting corrosion between the metal liner and shell. This systematic review reports outcomes following THR using MDM components. It was registered with PROSPERO and conducted in line with Cochrane and PRISMA recommendations. Sixteen articles were included overall, with meta-analysis performed on relevant subsets using a random intercept logistic regression model. Estimated median incidence of ARMD requiring revision surgery within study follow-up period was 0.3% (95% CI 0.1 – 1.8%, from 11 cohort studies containing 1312 cases). Serum metal ion levels were mildly raised in 7.9% of cases, and significantly raised in 1.8%, but there was no correlation with worse clinical hip function scores within studies. Dislocation rate was 0.8%. Revision rate was 3.3%. There are mixed reports of wear on the backside of the metal liner from the acetabular shell and screw heads. Both implant design and component malseating are implicated, but currently it is unclear to what extent each factor is responsible. Studies were poor quality with high risk of confounding, especially from trunnion corrosion. We have made recommendations for further work. In the meantime, surgeons should be aware of the potential risk of ARMD when considering using an MDM prosthesis, and, if selecting one, must ensure proper seating of the liner and screws intraoperatively. Cite this article: EFORT Open Rev 2021;6:343-353. DOI: 10.1302/2058-5241.6.200146