Aims. Conventional patient-reported surveys, used for patients undergoing total hip arthroplasty (THA), are limited by subjectivity and recall bias. Objective functional evaluation, such as gait analysis, to delineate a patient’s functional capacity and customize surgical interventions, may address these shortcomings. This systematic review endeavours to investigate the application of objective functional assessments in appraising individuals undergoing THA. Methods. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were applied. Eligible studies of THA patients that conducted at least one type of objective functional assessment both pre- and postoperatively were identified through Embase, Medline/PubMed, and Cochrane Central database-searching from inception to 15 September 2023. The assessments included were subgrouped for analysis: gait analysis, motion analysis, wearables, and strength tests. Results. A total of 130 studies using 15 distinct objective functional assessment methods (FAMs) were identified. The most frequently used method was instrumented gait/motion analysis, followed by the Timed-Up-and-Go test (TUG), 6 minute walk test, timed stair climbing test, and various strength tests. These assessments were characterized by their diagnostic precision and applicability to daily activities. Wearables were frequently used, offering cost-effectiveness and remote monitoring benefits. However, their accuracy and potential discomfort for patients must be considered. Conclusion. The integration of objective functional assessments in THA presents promise as a progress-tracking modality for improving patient outcomes. Gait analysis and the TUG, along with advancing wearable sensor technology, have the potential to enhance patient care, surgical planning, and rehabilitation. Cite this article: Bone Joint J 2024;106-B(8):764–774

Background: Anterior cruciate ligament (ACL) injury and re-injury rates are high and continue to rise in adolescents. After surgical reconstruction, less than 50% of patients return to their pre-injury level of physical activity. Clearance for return-to-play and rehabilitation progression typically requires assessment of performance during functional tests. Pain may impact this performance. However, the patient's level of pain is often overlooked during these assessments.

Purpose: To investigate the level of pain during functional tests in adolescents with ACL injury.

Fifty-nine adolescents with ACL injury (ACLi; female n=43; 15 ± 1 yrs; 167.6 ± 8.4 cm; 67.8 ± 19.9 kg) and sixty-nine uninjured (CON; female n=38; 14 ± 2 yrs; 165.0 ± 10.8 cm; 54.2 ± 11.5 kg) performed a series of functional tests. These tests included: maximum voluntary isometric contraction (MVIC) and isokinetic knee flexion-extension strength tests, single-limb hop tests, double-limb squats, countermovement jumps (CMJ), lunges, drop-vertical jumps (DVJ), and side-cuts. Pain was reported on a 5-point Likert scale, with 1 indicating no pain and 5 indicating extreme pain for the injured limb of the ACLi group and non-dominant limb for the CON group, after completion of each test. Chi-Square test was used to compare groups for the level of pain in each test. Analysis of the level of pain within and between groups was performed using descriptive statistics.

The distribution of the level of pain was different between groups for all functional tests (p≤0.008), except for ankle plantar flexion and hip abduction MVICs (Table 1). The percentage of participants reporting pain was higher in the ACLi group in all tests compared to the CON group (Figure 1). Participants most often reported pain during the strength tests involving the knee joint, followed by the hop tests and dynamic tasks, respectively. More specifically, the knee extension MVIC was the test most frequently reported as painful (70% of the ACLi group), followed by the isokinetic knee flexion-extension test, with 65% of ACLi group. In addition, among all hop tests, pain was most often reported during the timed 6m hop (53% of ACLi), and, among all dynamic tasks, during the side-cut (40% of ACLi) test (Figure 1). Furthermore, the tests that led to the higher levels of pain (severe or extreme) were the cross-hop (9.8% of ACLi), CMJ (7.1% of ACLi), and the isokinetic knee flexion-extension test (11.5% of ACLi) (Table 1).

Adolescents with and without ACL injury reported different levels of pain for all functional tasks, except for ankle and hip MVICs. The isokinetic knee flexion-extension test resulted in greater rates of severe or extreme pain and was also the test most frequently reported as painful. Functional tests that frequently cause pain or severe level of pain (e.g., timed 6m and cross hops, side-cut, knee flexion/extension MVICs and isokinetic tests) might not be the first test choices to assess function in patients after ACL injury/reconstruction. Reported pain during functional tests should be considered by clinicians and rehabilitation team members when evaluating a patient's readiness to return-to-play.

For any figures or tables, please contact the authors directly.

The aim of this trial was to assess the clinical examination findings commonly used for the ACL deficient knee. For reliability testing and criterion validation 102 patients with ACL injuries were assessed by a single observer, 35 by a second observer and 47 again by the initial observer. For construct and criterion validation 30 patients were assessed pre-operatively and a mean of 1.7 years after ACL reconstruction. The Lysholm 11, Tegner and Cincinnati outcome measures were assessed along with instrumented knee laxity (Stryker test), the one hop test (OHT) and graded tests (including anterior draw, Lachman test, quality of end point, and pivot shift test). The outcome measures were found to be reliable except the Cincinnati system. All examination findings were of unsatisfactory reliability, with the exception of the OHT and the Stryker test. Construct validation revealed a significant improvement in all outcome measure scores and examination findings following ACL reconstruction. Criterion validation revealed that of the examination findings only the OHT had a satisfactory correlation with the symptom of giving way and the Lysholm/Tegner measures. Comparison of the difference between the desired and actual Tegner activity levels with the examination findings revealed an improvement in all levels of correlation. With the exception of the OHT, the clinical examination findings used for the ACL deficient knee are unreliable and correlate poorly with the functional outcome of the patient. They may, however, have some benefit in assessment of deficiency of the anatomical structures and the findings should be presented individually, rather than forming part of the functional assessment of the patient

Background and Objective: The influence of back pain on work status is normally implied from the severity of the functional limitations. The aim of this cross sectional study was to analyse whether functional assessment instruments correlate well with impact on work status. Patients and Methods: 375 chronic low back pain patients attending back pain outpatient clinics of a University Hospital and a specialist rehabilitation centre over a period of one year were assessed. The three functional outcome scores measured were Oswestry Disability Index (ODI), Roland Morris disability questionnaire (RMQ) and Orebro Musculoskeletal Pain Questionnaire (OMPQ). The effect of back pain on patient’s work status was recorded in 6 options – work not affected, slightly affected, seriously affected, reduced number of hours, change job or give up job. The work status score was then correlated to the above three instrument values. Results: There was good correlation among the three instrument values (rho > 0.70) suggesting they are interchangeable. However, there was only a modest correlation between the work status scale and the three functional scores; the rho values were 0.47 for OMPQ, 0.43 for ODI and 0.39 for RMQ. There was no influence of age, duration of pain or type of work on this correlation. Conclusion: Back pain instruments (which measure pain and functional limitations) and work status are not interchangeable. The impact on work status cannot be implied from these functional scores and should be recorded as a separate outcome measure

Several studies have reported the assessment of the femoral head coverage on plane radiograph and CT data in supine position, though young patients with the dysplastic hip often have symptoms during activities such as standing, walking, and running. On the other hand, some investigators have used a method of CT which allows standardization of the femoral head coverage against an anterior pelvic plane based on the anterior superior iliac spines and the pubic tubercle. We believe both the weight-bearing position and the standardized position to be more relevant for diagnosis and preoperative surgical assessment. So, we show the femoral head coverage in standardized position using 3D-CT method and in weight-bearing position using the plane radiograph and the three-dimensional lower extremity alignment assessment system before and after Curved periacetabular osteotomy (CPO). Especially the covered volume of the femoral head, a new concept, using the three-dimensional lower extremity alignment assessment system which differs from the affected area and is measured by the ratio of the covered area in the medial part of the line connecting the anterior point of the acetabulum with the posterior to the femoral head area in each axial slice, superior slices than the slice passing through the femoral head center, obtained from the reproduced 3D model of the pelvis and the femur in standing position allows us to integrate various measurements reported by past researchers. We studied the consecutive 16 patients treated with CPO. In standardized position the sagittal sectional angles on the slice passing through the femoral head center using 3D-CT method gave us how the anterior, lateral, and posterior coverage was lack compared with normal subjects and whether the adequate transfer of the rotated fragment was performed after operation. The covered volume of the femoral head decides generally the deficiency or the adequateness. In standing position, though the pelvic tilt changes, the femoral head coverage on plane radiograph, representation by the CE angle, the VCA angle, AHI and ARO, was significantly improved, and the covered volume of the femoral head was significantly improved from 25.7% preoperatively to 51.1% postoperatively. Our study showed the improvement of the femoral head coverage, including the covered volume of the femoral head as a new concept, after CPO in weight-bearing and standardized position. The morphological and functional assessment of the femoral head coverage on both pre- and post-CPO should be performed because we can obtain the objective information in standardized position and the femoral head coverage in standing position is closely connected with the pain

Introduction

There is a growing recognition that evaluation should use patient-reported outcome tools and assessments of satisfaction in procedures like total knee replacement. These ensure that the patient's perception of outcome is included in the evaluation. Considering the increasing demands on physical function from the aging population, it is important to evaluate demanding physical activities for the population with end stage arthritis assigned for TKR.

Introduction & aims

Total knee Arthroplasty has revolutionized the lifestyle of patients with end stage knee arthritis. This study was conducted to describe the outcome from patient's perspective one year after TKR and patient satisfaction in terms of post operative pain and functional outcome Also, to identify preoperative characteristics predicting post operative outcome.

Purpose: Evaluation of a hands free crutch. This interesting device is intended for patients who have undergone foot and ankle surgery and should be non-weight bearing. It involves a knee tray attached to a vertical beam with a rubber foot. The crutch is strapped to the lower limb and weight is transferred though the proximal tibia.

Methods: Five Volunteers were assessed using the crutch, the K9 walker and 2 standard crutches in a simulated environment.

A comparison was made between this device and the K9 walker which has been shown to be a liberating walking aid indoors. Tasks from activities of daily living, productivity and transfers were included. Assessment was undertaken by the Occupational Therapy Team.

The hands free crutch was also compared with non weight bearing using two crutches to gauge performance outdoors. Assessment of ease of use and safety was undertaken by the Physiotherapy Team.

Results: Domestic chores including cleaning, cooking and shopping were possible using this device. Sitting activities were noted to be more difficult, because of the necessity to remove the crutch on each occasion.

Although speed was significantly greater (p< 0.0001.) using two crutches, the hands free crutch permitted safe outdoor mobilisation on even or uneven ground, up and down slopes with a gradient of 1 in 10 and up and down stairs. Good single leg stance stability was predictive of ease of use and safety for the hands free crutch.

Discussion: The hands free crutch is suited to motivated and physically able patients. Other lower limb pathology contraindicates the use of this device, but in patients with upper limb pathology it would permit non-weight bearing mobilisation. Good balance is paramount and perhaps a falls risk assessment should be performed prior to use.

The aim of the present study is to compare the Oxford Shoulder Score (OSS), the Shoulder Pain and Disability Index (SPADI) and the SF36 in terms of their correlation and sensitivity to change in a group of patients with subacromial impingement.

Patients attending a specialist shoulder clinic over a six-month period with a diagnosis of subacromial impingement completed the OSS, SPADI and SF36 on each of up to four attendances at six-week intervals, regardless of treatment. The data were analysed by creating scatter plots for each scoring system compared with each other, calculation of correlation coefficients, and calculating the effect size for each scale between subsequent visits (the difference in mean score divided by the standard deviation of the change in score for all individuals). This is a measure of sensitivity to change.

Three-hundred and twenty-three sets of scores were obtained in 110 patients. Scores were recorded across the whole range of the OSS and SPADI in our population. Similarly, the physical functioning component of the SF 36 ranged from 0 to 100. However, total SF 36 scores ranged only from 478 to 831.

There was good correlation between the OSS and SPADI scores (correlation coefficient = 0.86), although in 71% of observations the SPADI score was greater than the OSS when expressed as a percentage. The correlation between the OSS and SPADI was less good with the physical functioning component of the SF 36 (0.57 and 0.51 respectively), and worse with the total SF 36 (0.37 and 0.27 respectively) The OSS and SPADI showed good effect sizes (0.211 and 0.212) compared to the physical functioning and total SF 36 scores (0.104 and 0.063).

The OSS and SPADI show close correlation between each other, and were similarly sensitive to change in a group of patients with impingement. However, the SF 36 shows a poor spread of scores and less sensitivity to change in this group. These data support the use of the OSS or SPADI in these patients.

To assess total knee arthroplasty function in osteoarthritic patients who had their arthroplasty aged 55 years or less.

Self administered questionnaires were posted to 150 patients who had been registered on the Trent Regional Arthroplasty Register as having their TKA for osteoarthritis aged 55 or less. 85% of questionnaires were returned completed giving us information on 136 TKAs. The mean age of the patients at TKA was 51 yrs (Range 29 – 55 yrs.). Male 60: 67 Female. The mean follow-up was 44 months.

41% of patients had had no knee surgery prior to their TKA. 9 had had a corrective osteotomy.

51 patients had to give up work because of their osteoarthritic knee, only 17 got back to work after their TKA. 80% of patients felt that their arthroplasty had met or exceeded their pre-operative expectation in relieving pain though 41% continue to experience moderate or severe knee pain and 29% continue to have regular night pain. 62% of patients felt that they had been able to resume leisure activities to the same or better level than expected pre-operatively.

Introduction: To examine if an individual’s timed walk in sufficiently reproducible to correlate with the degree of spondylitic myelopathy and if surgical decompression has measurement effect on performance.

Methods: A 30mm timed walk, including a turn. The number of paces counted.

Forty-one non-myelopathic individuals were obtained. There was good inter-and intra-observer reliability.

Results: The mean control walking time and steps was 64.7 ± 8.4 seconds 46.9 ± 1.2 steps. The mean patients preoperative walking time and steps was 85.4 ± 11.2 seconds; 74.8 ± 5.3 steps and postoperative 64.7 ± 8.4 seconds; 63.5 ± 4.2 steps.

Significant improvement following surgery (p = 0.0018 and p = 5.87 x 10⁻⁶ respectively) and improvement maintained for at least two years after surgery.

Discussion and Conclusions:

The test is reproducible and reliable with good sensitivity and specificity.

Reconstruction of the shoulder joint following resection of the proximal humerus for bone tumours remains controversial. We report the long term functional results of the simplest form of reconstruction – an endoprosthesis.

One hundred patients underwent endoprosthetic replacement of the proximal humerus between 1976 and 1998. Thirty eight had osteosarcoma, 17 had chondrosarcoma, 16 had metastases and 9 had Ewing’s sarcoma. Mean age was 36 years (range 10 to 80 yrs). Survivorship of patients and prostheses were calculated. Function was assessed using the Musculoskeletal tumour society (MSTS) and Toronto extremity salvage (TESS) scoring systems. Thirty patients could come to the clinics for MSTS scoring and 38 out of 49 alive patients replied to the TESS questionnaires sent out to them.

The overall survival of the patients was 42% at 10 years. Local recurrence (LR) arose in 16 patients, being most common in chondrosarcoma (26%) and osteosarcoma (22%) and arose in 50% of patients with these tumours who had marginal excisions. Of these 16 patients, 8 had forequarter amputations whilst the remainder had excisions and radiotherapy. Mean time to LR was 12 months and all but two of these 16 patients subsequently died within a mean of 18 months.

The prostheses proved reliable and dependable. Only 9 required further surgery of any sort, 2 needing minor surgery to correct subluxation and 7 needing revisions, one for infection after radiotherapy and six for loosening – three after trauma. The survivorship of the prosthesis without any further surgery was 86. 5% at 20years. The survivorship of the limb without amputation was 93% at 20 years.

The functional outcome was very predictable. Most patients had only 45 degrees of abduction although three patients had normal movements. The mean MSTS functional score was 79% and the mean TESS score was also 79%. There was a high level of patient satisfaction but difficulty was encountered especially in lifting and in all activities above shoulder height. Endoprosthetic replacement of the proximal humerus is a predictable procedure providing reasonable function of the arm below shoulder height. The endoprostheses have proved highly dependable with a low re-operation rate. There is a high risk of local recurrence after inadequate surgery which should be avoided if possible.

We assessed the outcome after simultaneous multiple operations performed on 18 children with spastic diplegia, with emphasis on the changes in the physiological cost index (PCI) of walking. Fourteen patients had a measurable reduction at one year, but the more severely affected patients took up to two years to reach a new functional plateau. The level of the preoperative PCI allows prediction of the outcome of surgery in terms of reducing the effort of walking, or improving its appearance only. Intrapelvic intramuscular psoas tenotomy produced an improvement of hip flexion deformity in 15 of 17 patients without the loss of muscle power to initiate the swing phase. Fractional lengthening corrected hamstring tightness in 17 cases, and the mean popliteal angle was reduced from 63 degrees preoperatively to 30.2 degrees, with almost complete resolution of the fixed knee flexion deformity present in ten patients. Distal transfer of the rectus femoris, when it was shown to be contracting inappropriately, improved the knee flexion arc during walking from a mean of 28.3 degrees to 45.2 degrees.

Objectives

Patient function after arthroplasty should ideally quickly improve. It is not known which peri-operative function assessments predict length of stay (LOS) and short-term functional recovery. The objective of this study was to identify peri-operative functions assessments predictive of hospital LOS and short-term function after hospital discharge in hip or knee arthroplasty patients.

Aims. The aims were to assess whether joint-specific outcome after total knee arthroplasty (TKA) was influenced by implant design over a 12-year follow-up period, and whether patient-related factors were associated with loss to follow-up and mortality risk. Methods. Long-term follow-up of a randomized controlled trial was undertaken. A total of 212 patients were allocated a Triathlon or a Kinemax TKA. Patients were assessed preoperatively, and one, three, eight, and 12 years postoperatively using the Oxford Knee Score (OKS). Reasons for patient lost to follow-up, mortality, and revision were recorded. Results. A total of 94 patients completed 12-year functional follow-up (62 females, mean age 66 years (43 to 82) at index surgery). There was a clinically significantly greater improvement in the OKS at one year (mean difference (MD) 3.0 (95% CI 0.4 to 5.7); p = 0.027) and three years (MD 4.7 (95% CI 1.9 to 7.5); p = 0.001) for the Triathlon group, but no differences were observed at eight (p = 0.331) or 12 years’ (p = 0.181) follow-up. When assessing the OKS in the patients surviving to 12 years, the Triathlon group had a clinically significantly greater improvement in the OKS (marginal mean 3.8 (95% CI 0.2 to 7.4); p = 0.040). Loss to functional follow-up (53%, n = 109/204) was independently associated with older age (p = 0.001). Patient mortality was the major reason (56.4%, n = 62/110) for loss to follow-up. Older age (p < 0.001) and worse preoperative OKS (p = 0.043) were independently associated with increased mortality risk. An age at time of surgery of ≥ 72 years was 75% sensitive and 74% specific for predicting mortality with an area under the curve of 78.1% (95% CI 70.9 to 85.3; p < 0.001). Conclusion. The Triathlon TKA was associated with clinically meaningful greater improvement in knee-specific outcome when compared to the Kinemax TKA. Loss to follow-up at 12 years was a limitation, and studies planning longer-term functional assessment could limit their cohort to patients aged under 72 years. Cite this article: Bone Jt Open 2024;5(10):911–919

Background. Trunk muscles play an important role in supporting the spinal column. A decline in trunk muscle mass, as measured by bioelectrical impedance analysis (TMM–BIA), is associated with low back pain and poor quality of life. Purpose. The purpose of this study was to determine whether TMM–BIA correlates with quantitative and functional assessments traditionally used for the trunk muscles. Methods. We included 380 participants (aged ≥ 65 years; 152 males, 228 females) from the Shiraniwa Elderly Cohort (Shiraniwa) study, for whom the following data were available: TMM–BIA, lumbar magnetic resonance imaging (MRI), and back muscle strength (BMS). We measured the cross-sectional area (CSA) and fat-free CSA of the paravertebral muscles (PVM), including the erector spinae (ES), multifidus (MF), and psoas major (PM), on an axial lumbar MRI at L3/4. The correlation between TMM–BIA and the CSA of PVM, fat-free CSA of PVM, and BMS was investigated. Results. TMMBIA correlated with the CSA of total PVM and each individual PVM. A stronger correlation between TMM–BIA and fat-free CSA of PVM was observed. The TMM–BIA also strongly correlated with BMS. Conclusion. TMM–BIA is an easy and reliable way to evaluate the trunk muscle mass in a clinical setting. Conflict of interest. None. Sources of funding. None

Thumb carpometacarpal joint (CMCJ) arthritis is a common and debilitating condition. The mainstay of surgical management is Trapeziectomy. Concerns about possible functional implications of collapse of the metacarpal into the arthroplasty space as well as the potential for scaphometacarpal led to the development of techniques to try and prevent this. The purpose of this study was to investigate if there were any significant differences in the long-term outcomes of patients who participated in a randomized trial of trapeziectomy alone compared with trapeziectomy with ligament reconstruction and tendon interposition (LRTI). Sixty-five patients participated in our original trial, the 1 year findings of which were published in 2007. These patients were invited for a follow-up visit at a mean of 17 years (range 15–20) postoperatively. Twenty-eight patients attended, who had 34 operations, 14 trapeziectomy alone and 20 with LRTI. Patients were asked to complete a visual analogue scale (VAS) for satisfaction with the outcome of their procedure, rated on a scale from 0 (most dissatisfied) to 100 (most satisfied). They also completed the short version of the Disabilities of the Arm, Shoulder and Hand Score (QuickDASH) at their appointment. They underwent a functional assessment with a hand therapist and had a radiograph of the thumb. There were no statistically significant differences between the two groups in terms of satisfaction with surgery or functional outcomes, with most measurements showing minimal or no differences in means between the two groups. There was no difference in the space between the metacarpal and scaphoid on radiograph. Radial abduction was the only parameter that was significantly greater in the patients with simple trapeziectomy (median 79°) compared with trapeziectomy with LRTI (median 71°) (p = 0.04). Even at 17 years there is no significant benefit of LRTI over trapeziectomy alone for thumb carpometacarpal joint osteoarthritis

Aims. To evaluate mid-to long-term patient-reported outcome measures (PROMs) of endoprosthetic reconstruction after resection of malignant tumours arising around the knee, and to investigate the risk factors for unfavourable PROMs. Methods. The medical records of 75 patients who underwent surgery between 2000 and 2020 were retrospectively reviewed, and 44 patients who were alive and available for follow-up (at a mean of 9.7 years postoperatively) were included in the study. Leg length discrepancy was measured on whole-leg radiographs, and functional assessment was performed with PROMs (Toronto Extremity Salvage Score (TESS) and Comprehensive Outcome Measure for Musculoskeletal Oncology Lower Extremity (COMMON-LE)) with two different aspects. The thresholds for unfavourable PROMs were determined using anchor questions regarding satisfaction, and the risk factors for unfavourable PROMs were investigated. Results. The thresholds for favourable TESS and COMMON were 64.8 and 70.4 points, respectively. Multivariate analysis showed that age at surgery (p = 0.004) and postoperative leg length discrepancy (p = 0.043) were significant risk factors for unfavourable TESS results, while age at surgery (p < 0.001) was a significant risk factor for unfavourable COMMON-LE results. Following receiver operating characteristic analysis, the threshold for both TESS and COMMON-LE was 29 years of age at surgery. Additionally, a leg length discrepancy of 8.2 mm was the threshold for unfavourable TESS. Conclusion. Patients aged > 29 years at the time of surgery require appropriate preoperative counselling and adequate postoperative physical and socioemotional support. Reconstruction equivalent to the length of the resected bone can reduce the risk of functional disabilities in daily living. Cite this article: Bone Jt Open 2023;4(12):906–913

Aims. The primary aim of this study is to assess the survival of the uncemented hydroxyapatite (HA) coated Trident II acetabular component as part of a hybrid total hip arthroplasty (THA) using a cemented Exeter stem. The secondary aims are to assess the complications, joint-specific function, health-related quality of life, and radiological signs of loosening of the acetabular component. Methods. A single-centre, prospective cohort study of 125 implants will be undertaken. Patients undergoing hybrid THA at the study centre will be recruited. Inclusion criteria are patients suitable for the use of the uncemented acetabular component, aged 18 to 75 years, willing and able to comply with the study protocol, and provide informed consent. Exclusion criteria includes patients not meeting study inclusion criteria, inadequate bone stock to support fixation of the prosthesis, a BMI > 40 kg/m. 2. , or THA performed for pain relief in those with severely restricted mobility. Results. Implant survival, complications, functional outcomes and radiological assessment up to ten years following index THA (one, two, five, seven, and ten years) will be performed. Functional assessment will include the Oxford Hip Score, Forgotten Joint Score, 12-Item Short Form Health Survey, EuroQol five-dimension health questionnaire, and pain and patient satisfaction. Radiological assessment with assess for acetabula lucent lines, lysis, and loosening according to DeLee and Charnley zones. Conclusion. This study is part of a stepwise introduction of a new device to orthopaedic practice, and careful monitoring of implants should be carried out as part of the Beyond Compliance principles. The results of this study will provide functional, radiological, and survival data to either support the ongoing use of the HA acetabulum or highlight potential limitations of this new implant before wide adoption. Cite this article: Bone Jt Open 2023;4(10):782–790

Sarcopenia is an age-related geriatric syndrome which is associated with subsequent disability and morbidity. Currently there is no promising therapy approved for the treatment of sarcopenia. The receptor activator of nuclear factor NF-κB ligand (RANKL) and its receptor (RANK) are expressed in bone and skeletal muscle. Activation of the NF-κB pathway mainly inhibits myogenic differentiation, which leads to skeletal muscle dysfunction and loss. LYVE1 and CD206 positive macrophage has been reported to be associated with progressive impairment of skeletal muscle function with aging. The study aims to investigate the effects of an anti-RANKL treatment on sarcopenic skeletal muscle and explore the related mechanisms on muscle inflammation and the polarization status of macrophages. Sarcopenic senescence-accelerated mouse P8 (SAMP8) mice at month 8 were treated intraperitoneally with 5mg/kg anti-RANKL (IK22/5) or isotype control (2A3; Bio X Cell) antibody every 4 weeks and harvested at month 10. Senescence accelerated mouse resistant-1 (SAMR1) were collected at month 10 as the age-matched non-sarcopenic group. Ex-vivo functional assessment, grip strength and immunostaining of C/EBPa, CD206, F4/80, LYVE1 and PAX7 were performed. Data analysis was done with one-way ANOVA, and the significant level was set at p≤0.05. At month 10, tetanic force/specific tetanic force, twitch force/specific twitch force in anti-RANKL group were significantly higher than control group (all p<0.01). The mice in the anti-RANKL treatment group also showed significantly higher grip strength than Con group (p<0.001). The SAMP8 mice at month 10 expressed significantly more C/EBPa, CD206 and LYVE1 positive area than in SAMR1, while anti-RANKL treatment significantly decreased C/EBPa, CD206 and LYVE1 positive area. The anti-RANKL treatment protected against skeletal muscle dysfunctions through suppressing muscle inflammation and modulating M2 macrophages, which may represent a novel therapeutic approach for sarcopenia. Acknowledgment: Collaborative Research Fund (CRF, Ref: C4032-21GF)