Robotic Arthroplasty Clinical and cost Effectiveness Randomised controlled trial (RACER-knee): a study protocol.

INTRODUCTION: Robotic-assisted knee replacement systems have been introduced to healthcare services worldwide in an effort to improve clinical outcomes for people, although high-quality evidence that they are clinically, or cost-effective remains sparse. Robotic-arm systems may improve surgical accuracy and could contribute to reduced pain, improved function and lower overall cost of total knee replacement (TKR) surgery. However, TKR with conventional instruments may be just as effective and may be quicker and cheaper. There is a need for a robust evaluation of this technology, including cost-effectiveness analyses using both within-trial and modelling approaches. This trial will compare robotic-assisted against conventional TKR to provide high-quality evidence on whether robotic-assisted knee replacement is beneficial to patients and cost-effective for healthcare systems. METHODS AND ANALYSIS: The Robotic Arthroplasty Clinical and cost Effectiveness Randomised controlled trial-Knee is a multicentre, participant-assessor blinded, randomised controlled trial to evaluate the clinical and cost-effectiveness of robotic-assisted TKR compared with TKR using conventional instruments. A total of 332 participants will be randomised (1:1) to provide 90% power for a 12-point difference in the primary outcome measure; the Forgotten Joint Score at 12 months postrandomisation. Allocation concealment will be achieved using computer-based randomisation performed on the day of surgery and methods for blinding will include sham incisions for marker clusters and blinded operation notes. The primary analysis will adhere to the intention-to-treat principle. Results will be reported in line with the Consolidated Standards of Reporting Trials statement. A parallel study will collect data on the learning effects associated with robotic-arm systems. ETHICS AND DISSEMINATION: The trial has been approved by an ethics committee for patient participation (East Midlands-Nottingham 2 Research Ethics Committee, 29 July 2020. NRES number: 20/EM/0159). All results from the study will be disseminated using peer-reviewed publications, presentations at international conferences, lay summaries and social media as appropriate. TRIAL REGISTRATION NUMBER: ISRCTN27624068.

Plate fixation of midshaft clavicle fractures for delayed union and non-union is a cost-effective intervention but functional deficits persist at long-term follow-up.

Background: The primary aim of this study was to compare the long-term functional outcome of midshaft clavicle fracture fixation for delayed (≥3 month) and non-union (≥6 month) compared to a matched cohort of patients that achieved union with non-operative management. The secondary aim was to assess cost-effectiveness of fixation. Methods: A consecutive series of patients over 10-years were retrospectively reviewed using the QuickDASH, Oxford Shoulder Score and EuroQol five-dimension summary index (EQ-5D). These patients were compared to a matched cohort that achieved union after non-operative management using propensity score matching. Results: Sixty patients (follow-up 79%, n = 60/76) at 4.1 years post-operative (1.1-10.0 years) had a QuickDASH of 16.5 (95% CI 11.6-21.5), Oxford Shoulder Score 41.5 (39.0-44.1) and EQ-5D 0.7621 (0.6822-0.8421). One in five patients were dissatisfied with their final outcome (n = 13/60). Functional outcome was inferior following fixation when compared to patients that united with non-operative management (QuickDASH 16.5 vs. 5.5, p < 0.001 and EQ-5D 0.7621 vs. 0.9073, p = 0.001). However, significant improvements were found when compared to pre-operative scores (QuickDASH p < 0.001 and EQ-5D p < 0.001). The cost per QALY for fixation was £5624.62 for the study cohort. Conclusions: Clavicle fixation for delayed and non-union is a cost-effective intervention but outcomes are worse compared to patients that unite with non-operative management.

Shoulder exostoses in hereditary multiple exostoses: probability of surgery and malignant change.

HYPOTHESIS: Patients with hereditary multiple exostoses (HME) in association with palpable shoulder exostoses are more severely affected by their disease. MATERIALS AND METHODS: From a prospective database of 78 families with HME identified, 172 patients were identified. Demographic details, deformity, functional scores, standing height, number of exostoses, site, exostosin genotype (EXT1 and EXT2), surgical excision, and malignant change were recorded. Nonparametric tests were used to compare patients with and without shoulder exostoses (clavicle, scapula, and humerus). RESULTS: There were 5361 palpable exostoses, of which 14% were of the shoulder and were present in 145 patients (84.3%). There was a younger mean age (26.8 vs 37.9 years) and a male predominance in those individuals with shoulder exostoses (P = .0005). Patients with shoulder exostoses had significantly worse disease (P < .05). EXT1 mutations were more commonly observed in those with shoulder exostoses (odds ratio [OR], 20.6; 95% confidence interval [CI], 11.2-28.5; P = .001). The likelihood of surgical excision was greater in those with shoulder exostoses (OR, 2.8) and highest for scapular exostoses (OR, 3.7). Risk factors for surgical excision of shoulder exostoses were younger age (P = .03) and male gender (P < .008). Seven chondrosarcomas occurred, 2 scapular and a proximal humeral. The probability of malignant change of was highest for palpable scapular exostoses relative to any other anatomic site (OR, 12.3; P = .05). CONCLUSION: Shoulder exostoses have a male predominance, and patients are more likely to have an EXT1 mutation. The presence of shoulder exostoses could serve as a tool to identify those individuals at high probability of malignant change. DISCUSSION: The existence of shoulder exostoses identifies those individuals with a high probability of having an EXT1 genotype (OR 20.6, 94.4% sensitivity, 84.8% positive predictive value), which is associated with sarcomatous change.

The metal-backed glenoid component in rheumatoid disease: eight- to fourteen-year follow-up.

HYPOTHESIS: We believe the variable reported survivorship of the metal-backed glenoid is related to the design of the component. This study reports the outcome and survivorship of the uncemented glenoid in rheumatoid patients with an intact or repairable rotator cuff at surgery, and considers the key design features that may predict longevity of this component. METHOD: Forty-six shoulders in 39 patients (31 women), with a mean age of 55 years (range, 35-86 years) received a total shoulder replacement with a screw-fixed porous coated metal-back glenoid. Twenty-nine patients (36 shoulders) were monitored for a mean of 132 months (96-168 months), and 10 were lost to follow-up or died before 8 years of follow-up. A Constant score was measured preoperatively and annually from the time of surgery. Radiographs were assessed for lucency, loosening, and superior subluxation of the humeral head. RESULTS: The Constant score improved from a mean of 20.6 preoperatively to 33.5 at last follow-up (P < .001). Implant survivorship at 10 years was 89%. Five were revised: 3 for pain with associated superior subluxation, 1 for infection, and 1 for aseptic loosening. In the 4 patients with lucent zones around the glenoid, superior subluxation of the humeral head had occurred 2 to 4 years before the observed lucent lines. DISCUSSION: The uncemented glenoid performs well in the rheumatoid shoulder, giving pain relief and improved functional outcome. The survivorship is comparable to previously reported studies. CONCLUSION: We believe the key design features in the survivorship of the metal-backed glenoid are: a low-profile tray, with a fully coated bone ingrowth substance at the plate-bone interface, a conical stem, and secure screw fixation.

Oxford shoulder score in a normal population.

BACKGROUND: The function of the asymptomatic normal shoulder may differ according to gender and could also deteriorate with age. This may result in a disparity in the normal Oxford shoulder score (OSS) according to these variables. If a difference were to exist an adjusted OSS, for age and gender, could be calculated from the raw score using the expected normal score. AIM: The aim of this study was to define a normal OSS in an asymptomatic population according to age and gender. MATERIALS AND METHODS: During the study period 202 patients aged from 20 years to 99 years with subjectively asymptomatic shoulders completed an OSS. These patients presented to the study center during a 1 week period for management of disorders out with their shoulder girdle. Patients with a known prior shoulder pathology, injury, or polyarthropathy were excluded. RESULTS: The mean OSS varied according age and gender. There was a significant correlation between age and the OSS, with an increasing score (worse) being associated with older age (r = 0.62, P < 0.0001). The mean OSS for females was 18.8 (12-42, SD 5.4) and for males was 16.3 (12-30, SD 4.5), this difference was significant (P = 0.0001). We propose that a normalized OSS could be calculated as a percentage by the using the expected normal for that patient's age and gender as demonstrated in this study ((raw score/normal score) × 100). CONCLUSION: Our study provides normal data for an urban population presenting to orthopedic services and allows for a relative OSS to be calculated from the raw score.

Skeletal growth patterns in hereditary multiple exostoses: a natural history.

Hereditary multiple exostoses (HME) is a commonly inherited musculoskeletal condition and is associated with a diminished stature. We demonstrated that adults with HME were significantly shorter when compared with a control group (P<0.001); preadolescents, however, were significantly taller than predicted (P=0.01). This was reflected by their height centile; 58% of the adults were under the 25th centile, whereas 53% of the preadolescence group were above the 75th centile. Stature was more severely affected in patients with an EXT1 mutation (P=0.008). This study illustrates a novel age-related growth pattern associated with HME, which is also affected by genotype.

Medium-term results of Oxford phase-3 medial unicompartmental knee arthroplasty.

PURPOSE: To review medium-term results of 49 consecutive patients who underwent Oxford phase-3 medial unicompartmental knee arthroplasty by a single surgeon. METHODS: Records of 28 women (mean age, 71 years) and 21 men (mean age, 68 years) who underwent minimally invasive Oxford phase-3 medial unicompartmental knee arthroplasty by a single surgeon were retrospectively reviewed. The Oxford knee score and visual analogue scale (VAS) scores for pain and satisfaction were assessed at the latest follow-up by an independent observer, as were postoperative radiographs for implant position, osteoarthritic changes in the non-replaced compartments, and radiolucent lines of >2 mm or implant subsidence. The survival rate was calculated using Kaplan-Meier survival analysis. Patient demographics, postoperative alignment (varus/ valgus), Oxford knee scores, and the progression of osteoarthritis in the other compartments were included in a multiple logistic regression (MLR) analysis to identify significant factors affecting the probability of being satisfied (VAS scores for satisfaction of ≤2). RESULTS: The mean follow-up duration was 7.2 years. No patient was lost to follow-up. Two patients with no knee symptoms died (unrelated to surgery) before the 5-year follow-up. The cumulative survival rate at the 9-year follow-up was 91.2% (95% confidence interval, 87.6-94.5%). There were 4 early failures (before 4 years). One patient early in the series developed avascular necrosis of the lateral femoral condyle with an over-corrected tibiofemoral valgus of 12º at 8 months; the other 3 complained of anterior knee pain, without signs of osteoarthritis. All 4 patients underwent revision with total knee arthroplasty. There were 43 patients with more than 5 years of follow-up and without revision of the prosthesis. Patients who were not satisfied (n=6) were more likely to be <65 years old (n=4, adjusted odds ratio [OR], 3.1; MLR p=0.002) and male (n=4; adjusted OR, 2.3; MLR p=0.02). Six of the 43 patients had lucent lines on radiographs, all of which were partial and under the tibial component. Progression of the arthritis in the patellofemoral and/or lateral compartments was worse in 5 patients. CONCLUSION: Careful patient selection and good surgical technique contributed to good outcome. Younger male patients should be counselled regarding the higher chance of limited satisfaction.

Malignant lesions are rare in medial third of the clavicle in children: the European Juvenile Medial End of Clavicle Tumour study.

Condensing osteitis is a condition presenting to all paediatric orthopaedic services, but the prevalence of the condition and optimal management is difficult to determine from the literature. Many case reports in the orthopaedic literature describe biopsy to exclude malignancy as mandatory, whereas expert radiological opinion has suggested that lesions can be classified as typical of sclerosing osteitis on imaging alone. The aim of this study was to calculate an accurate incidence of malignancy at the medial end of the clavicle in children based on data held by national and regional cancer registries in Europe. In addition, this study determined the published success of biopsy in identifying a causative organism. The investigators wrote to 173 European national or regional cancer registries requesting the number of malignant lesions at the medial end of the clavicle in those less than 19 years of age, how long the registry had been in existence and the size of the population served. A literature review was conducted of Medline and Pubmed using the terms, 'condensing osteitis,' 'chronic recurrent multiostotic osteomyelitis,' 'acute osteomyelitis,' 'chronic osteomyelitis clavicle,' 'sclerosing osteitis' and 'sclerosing osteomyelitis' and refined to those regarding the clavicle. The incidence of malignancy at the medial end of the clavicle was found to be extremely low (one case every 275 child-years at risk). In addition, biopsy rarely identified a causative organism with only two of 89 biopsies being positive. We suggest that for a chronic nonmalignant process in which clinical features are typical, serial imaging with follow-up is sufficient although timely biopsy would be recommended when doubt exists.