Biomechanical Comparison of Distal Biceps Tendon Repair Techniques: Extracortical Single-Button Inlay Fixation Versus Intracortical Double-Button Onlay Anatomic Footprint Fixation.

BACKGROUND: Extracortical single-button (SB) inlay repair is a commonly used distal biceps tendon technique. However, complications (eg, neurovascular injury) and nonanatomic repairs have led to the development of intracortical fixation techniques. PURPOSE: To compare the biomechanical stability of extracortical SB repair with an anatomic intracortical double-button (DB) repair technique. STUDY DESIGN: Controlled laboratory study. METHODS: The distal biceps tendon was transected in 18 cadaveric elbows from 9 donors. One elbow of each donor was randomly assigned to the extracortical SB or anatomic DB group. Both groups were cyclically loaded with 60 N over 1000 cycles between 90° of flexion and full extension. The elbow was then fixed in 90° of flexion and the repair construct loaded to failure. Gap formation and construct stiffness during cyclic loading and ultimate load to failure were analyzed. RESULTS: When compared with the extracortical SB technique after 1000 cycles, the anatomic DB technique showed significantly less gap formation (mean ± SD, 2.7 ± 0.8 vs 1.5 ± 0.9 mm; P = .017) and significantly more construct stiffness (87.4 ± 32.7 vs 119.9 ± 31.6 N/mm; P = .023). Ultimate load to failure was not significantly different between the groups (277 ± 93 vs 285 ± 135 N; P = .859). The failure mode in the anatomic DB group was significantly different from that of the extracortical SB technique (P = .002) and was due to fracture avulsion of the cortical button in 7 of 9 specimens (vs none in the SB group). CONCLUSION: Our study shows that the intracortical DB technique produces equivalent or superior biomechanical performance to that of the SB technique. The DB technique may offer a clinically viable alternative to the SB repair technique. CLINICAL RELEVANCE: This study suggests, at worst, an equivalent and, at best, a superior biomechanical performance of intracortical anatomic DB footprint repair at the time of surgery. However, the mode of failure suggests that this technique should not be used in patients with poor bone quality.

A Systematic Review of Long-term Clinical and Radiological Outcomes of Arthroscopic and Open/Mini-open Rotator Cuff Repairs.

BACKGROUND: Arthroscopic rotator cuff repair (aRCR) has shown similar midterm functional results and retear rates as open/mini-open rotator cuff repair (oRCR). A pooled analysis of long-term results of both techniques is yet missing. PURPOSE: To evaluate the long-term results of aRCR and oRCR for full-thickness rotator cuff tears. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: The systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The CENTRAL (Cochrane), MEDLINE (PubMed), and Embase databases were searched for studies that reported on long-term clinical and radiographic outcomes of full-thickness aRCR and oRCR with a minimum follow-up of 9 years. RESULTS: Eleven studies were included: 5 studies on aRCR and 6 studies on oRCR. Studies were based on 550 shoulders (539 patients) with a mean patient age of 56.3 years (range, 25-77). After a mean follow-up of 14.0 years (range, 9-20), the mean preoperative absolute Constant score (CS) and American Shoulder and Elbow Surgeons (ASES) shoulder score were significantly improved postoperatively (CS, 44 to 78 points; ASES, 52% to 91%; both comparisons, P < .001). The retear rate was 41% (141 of 342 shoulders) without a significant difference between groups (aRCR, 43%; oRCR, 39%) (P = .364). A retear was associated with significantly reduced CS as compared with a healed repair (P = .004). No significant differences were found in postoperative functional scores, complications, and retear rates after failed cuff repairs between the arthroscopic and open/mini-open repair groups. CONCLUSION: Pooled analysis of arthroscopic and open rotator cuff repairs demonstrated sustained improvement in long-term shoulder scores and pain with a substantial retear rate in both groups, which was associated with inferior shoulder function. There were no significant differences in long-term functional outcomes, retear rates, and complications. Both surgical techniques may be used on the basis of factors such as patient or surgeon preference and cost. Further studies using a more robust randomized controlled trial or larger cohort design are recommended to ascertain whether one surgical repair technique is superior to the other. REGISTRATION: CRD42020180448 (PROSPERO).

Biomechanical analysis of plating techniques for unstable lateral clavicle fractures with coracoclavicular ligament disruption (Neer type IIB).

BACKGROUND: Neer type IIB lateral clavicle fractures are inherently unstable fractures with associated disruption of the coracoclavicular (CC) ligaments. Because of the high rate of nonunion and malunion, surgical fixation is recommended; however, no consensus has been reached regarding the optimal fixation method. A new plating technique using a superior lateral locking plate with anteroposterior (AP) locking screws, resulting in orthogonal fixation in the lateral fragment, has been designed to enhance stability and reduce implant failure. The purpose of this study was to biomechanically compare 3 different clavicle plating constructs within a fresh frozen human cadaveric shoulder model. METHODS: Twenty-four fresh frozen cadaveric shoulders were randomized into 3 groups (n = 8 specimens): group 1, lateral locking plate only (Medartis Aptus Superior Lateral Plate); group 2, lateral locking plate with CC stabilization (No. 2 FiberWire); and group 3, lateral locking plate with 2 AP locking screws stabilizing the lateral fragment. All specimens were subject to cyclic loading of 70 N for 500 cycles. Data were analyzed for gap formation after cyclic loading, construct stiffness, and ultimate load to failure, defined by a marked decrease in the load displacement curve. RESULTS: After 500 cycles, there was no statistically significant difference between the 3 groups in gap formation (P = .179). No specimen (0/24) failed during cyclic loading. Ultimate load to failure was significantly higher in group 3 compared to group 1 (286 N vs. 167 N; P = .022), but not to group 2 (286 N vs. 246 N; P = .604). There were no statistically significant differences in stiffness (group 1: 504 N/mm; group 2: 564 N/mm; group 3: 512 N/mm; P = .712). Peri-implant fracture was the primary mode of failure for all 3 groups, with group 3 demonstrating the lowest rate of peri-implant fractures (group 1: 6/8; group 2: 7/8; group 3: 4/8; P = .243). CONCLUSION: Biomechanical evaluation of the clavicle plating techniques showed effective fixation across all specimens at 500 cycles. The lateral locking plate with orthogonal AP locking screw fixation in the lateral fragment demonstrated the greatest ultimate failure load, followed by the lateral locking plate with CC stabilization. This new plating technique showed compatible stiffness and gap formation when compared to conventional lateral locking plates as well as plates with CC fixation. The use of orthogonal screw fixation in the distal fragment may negate against the need for CC stabilization in these types of fractures, thus minimizing surgical dissection around the coracoid and potential complications.

A new all-suture tension band tape fixation technique for simple olecranon fractures versus conventional tension band wire fixation: a comparative biomechanics study.

HYPOTHESIS: Simple transverse or short oblique olecranon fractures without articular comminution are classified as Mayo type IIA fractures and are typically treated with a tension band wire construct. Because of the high reoperation rates, frequently because of prominent hardware, all-suture tension band constructs have been introduced. It was the purpose to compare the biomechanical performance of conventional tension band wire fixation with a new all-suture tension band tape fixation for simple olecranon fractures. METHODS: Mayo type IIA olecranon fractures were created in 20 cadaveric elbows from 10 donors. One elbow of each donor was randomly assigned to the tension band wire technique (group TBW) or tension band tape (Arthrex, 1.3-mm SutureTape) technique (group TBT). Both groups were cyclically loaded with 500 N over 500 cycles, after which a uniaxial displacement was performed to evaluate load to failure. Data were analyzed for gap formation after cyclic loading, construct stiffness, and ultimate load to failure, where failure was defined as fracture gap formation greater than 4.0 mm. RESULTS: There was no significant difference in gap formation after 500 cycles between the TBW (1.8 mm ± 1.3 mm) and the TBT (1.9 mm ± 1.1 mm) groups (P = .854). The TBT showed a tendency toward greater construct stiffness compared with the TBW construct (mean difference: 142 N/mm; P = .053). Ultimate load to failure was not significantly different comparing both groups (TBW: 1138 N ± 286 N vs. TBT: 1126 N ± 272 N; P = .928). In both groups, all repairs failed because of >4.0-mm gap formation at the fracture site and none because of tension band construct breakage. CONCLUSIONS: Our study shows that the TBT technique produces equivalent or superior biomechanical performance to the TBW for simple olecranon fractures. The TBT approach reduces the risk of hardware prominence and as a result mitigates against the need for hardware removal. The TBT technique offers a clinically viable alternative to TBW.

Factors Influencing Acromial and Scapular Spine Strain after Reverse Total Shoulder Arthroplasty: A Systematic Review of Biomechanical Studies.

BACKGROUND: Acromial and scapular spine fractures after reverse total shoulder arthroplasty (RTSA) can be devastating complications leading to substantial functional impairments. The purpose of this study was to review factors associated with increased acromial and scapular spine strain after RTSA from a biomechanical standpoint. METHODS: A systematic review of the literature was conducted based on PRISMA guidelines. PubMed, Embase, OVID Medline, and CENTRAL databases were searched and strict inclusion and exclusion criteria were applied. Each article was assessed using the modified Downs and Black checklist to appraise the quality of included studies. Study selection, extraction of data, and assessment of methodological quality were carried out independently by two of the authors. Only biomechanical studies were considered. RESULTS: Six biomechanical studies evaluated factors associated with increased acromial and scapular spine strain and stress. Significant increases in acromial and scapular spine strain were found with increasing lateralization of the glenosphere in four of the included studies. In two studies, glenosphere inferiorization consistently reduced acromial strain. The results concerning humeral lateralization were variable between four studies. Humeral component neck-shaft angle had no significant effect on acromial strain as analysed in one study. One study showed that scapular spine strain was significantly increased with a more posteriorly oriented acromion (55° vs. 43°; p < 0.001). Another study showed that the transection of the coracoacromial ligament increased scapular spine strain in all abduction angles (p < 0.05). CONCLUSIONS: Glenoid lateralization was consistently associated with increased acromial and scapular spine strain, whereas inferiorization of the glenosphere reduced strain in the biomechanical studies analysed in this systematic review. Humeral-sided lateralization may increase or decrease acromial or scapular spine strain. Independent of different design parameters, the transection of the coracoacromial ligament resulted in significantly increased strains and scapular spine strains were also increased when the acromion was more posteriorly oriented. The results found in this systematic review of biomechanical in-silico and in-vitro studies may help in the surgical planning of RTSA to mitigate complications associated with acromion and scapular spine fracture.

Prosthesis Designs and Tuberosity Fixation Techniques in Reverse Total Shoulder Arthroplasty: Influence on Tuberosity Healing in Proximal Humerus Fractures.

Reverse total shoulder arthroplasty (RTSA) is increasingly used for the treatment of complex proximal humerus fractures and fracture sequelae. In 2021, half a dozen models of fracture stems are commercially available, reflecting its growing utility for fracture management. Prosthesis designs, bone grafting and tuberosity fixation techniques have evolved to allow better and more reliable fixation of tuberosities and bony ingrowth. Patients with anatomical tuberosity healing not only have an increased range of active anterior elevation and external rotation, but also experience fewer complications and longer prosthesis survival. This review provides an overview of recent evidence on basic and fracture-specific RTSA design features as well as tuberosity fixation techniques that can influence tuberosity healing.

GIS mapping of healthcare practices: do older adults have equitable access to dental and medical care in the UK?

Introduction Considering an ageing population with increasing comorbidities, access to oral and general healthcare is a growing concern. This study aimed to identify and compare access to dental and general practices. This study further aimed to ascertain if there exists a socioeconomic distribution of dental and general practices among older adults.Materials and methods A total of 13,007 dental practices and 13,759 general practices were mapped using geographic information system software, and overlaid with the UK older adult population and deprivation data by health areas. Data analysis was carried out by creating a geographical distribution map and by using descriptive statistics, Gini coefficients and Lorenz curves.Results NHS Central London Clinical Commissioning Group (CCG) held the highest dental practice-to-population ratio of 958 practices per 100,000 older adults, while NHS Manchester CCG held the highest general practice-to-population ratio of 264.4 general practices per 100,000 older adults. England had the highest Gini coefficients for general and dental practice at 0.214 and 0.195, respectively. Both dental and general practices were socioeconomically distributed among older adults in England, Wales and Northern Ireland, but not in Scotland.Conclusions An increasing proportion of older adults need access to healthcare that is based on clinical need, not the ability to pay; a founding principle of the NHS. This nation-wide study captures inequities in the spatial accessibility for older adults in the UK.

Dental specialist workforce and distribution in the United Kingdom: a specialist map.

Objectives To illustrate, identify and assess a contemporary model of the geographic distribution of specialist dentists in relation to population age groups and rurality.Methods All UK dental specialists registered with the General Dental Council were extracted and paired with publicly available locations of work. Geographic information system tools were used to map specialist locations against population and rural-urban classifications of England, Wales, Scotland and Northern Ireland. The latest 2019 population estimates and health board areas were superimposed to create a specialist map. All other data were collected at the smallest geographic statistical areas and corresponding population data from the latest census.Results A total of 4,439 specialist titles were held by 3,041 individuals, linked to 3,459 unique locations of work. Specialist locations were mapped against 135 Clinical Commissioning Groups (CCGs) of England, seven Local Health Boards of Wales, 14 Health Boards of Scotland and five Health and Social Care Trusts of Northern Ireland. NHS Central London CCG had the highest specialist dentists per 100,000 people at 118.9; paediatric dentists per 20,000 children at 6.4; orthodontic dentists per 20,000 schoolchildren at 23.2; oral surgery dentists at 4.8 per 20,000 adults; and prosthodontic dentists at 7.2 per 20,000 adults. Orthodontics and oral surgery had the highest specialist-to-population ratios at 1:45,545 and 1:77,510, compared to oral and maxillofacial radiology and oral microbiology with the lowest ratios of 1:2,178,316 and 1:9,024,452, respectively. In England, Wales, Scotland and Northern Ireland, there were 79.5% (n = 42,140,039), 55.6% (n = 1,703,248), 46.9% (n = 2,481,996) and 42.9% (n = 776,295) of the respective populations that lived within 2.5 km of a specialist location. There were significant disparities in rural proximity to specialist locations across all nations. In Scotland, 40.8% of the rural population lived outside 10 km of a specialist location.Conclusions Stark inequalities exist in the geographic distribution of UK specialist dentists and high disparities were found in accessing a specialist, especially for vulnerable populations.

Public transport access to NHS dental care in Great Britain.

Objective Access to transport is a common barrier to oral health. Greater dependence on public transport has shown delayed oral healthcare, lack of usual source of care and greater unmet health needs. This study examined the spatial accessibility of the population of Great Britain to public transport in providing access to oral healthcare.Methods A total of 8,791 dental practices in Great Britain were identified and geocoded. There were 10,444 rail, metro and light rail stops and 348,961 bus and tram stops. Geographic information systems were utilised to integrate the dental practice locations and public transport points to respective census tracts of each nation containing population data, deprivation measures, and classification of rural and urban areas.Results Almost all dental clinics in Great Britain were located within 400 m of bus and tram stops or 800 m of a rail, metro or light rail stop. Similarly, in Scotland and England, 92% lived within any public transport (within 400m of bus and tram stops or 800m of a rail, metro or light rail stop), and in Wales, 84.2% lived within any public transport stop. However, only 75.1%, 79.6% and 60.4% of the population of Scotland, England and Wales had access to a high-frequency bus stop, respectively. In Scotland, England and Wales, 40.7%, 33.7% and 38.3% of rural residents did not have access to any public transport and only 4.9%, 7.5% and 14.6% of the rural residents had access to an optimal bus stop, respectively. In Wales, 19.5% of older adults do not have access to a bus stop.Conclusion Some transport-disadvantaged groups do not have adequate access to public transport services. There is a compelling need to address public transport integration with oral health facilities to ensure equality in accessing integral services.

Disparities in the geographic distribution of NHS general dental care services in England.

Objectives To assess the geographic distribution of NHS dental practices in England in relation to deprivation and rurality.Methods A total of 7,851 dental practices in England were included in this study against a population of 53,004,517 from 171,349 statistical areas. The practices were mapped using geographic information systems technology and integrated with census population data, the Index of Multiple Deprivation and the rural-urban classification.Results Results showed that 92.1% of children and adolescents, 91.8% of working-age adults and 88.8% of older adults lived within 2.5 km of a practice. In general, dental practices were not socioeconomically distributed; 99.7% of people from the most deprived areas lived close to a practice compared to 92.9% of people from the least deprived areas. However, when age groups were delineated, much higher proportions of deprived children and adolescents lived within 2.5 km distance from a dental service, while the opposite was true for the older age group (high proportions of the least deprived older adults lived within 2.5 km distance from a dental service). In rural areas, 54.8%, 54.3% and 53.5% of children and adolescents, working-age adults and older adults lived outside 2.5 km of a dental practice, respectively.Conclusions Disparities exist in the distribution of NHS dental practices in England. The need to increase spatial availability of dental practices in England is evident.

Patient-Related Risk Factors for Unplanned 30-Day Hospital Readmission Following Primary and Revision Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

Total knee arthroplasty (TKA) is a highly effective procedure for advanced osteoarthritis of the knee. Thirty-day hospital readmission is an adverse outcome related to complications, which can be mitigated by identifying associated risk factors. We aimed to identify patient-related characteristics associated with unplanned 30-day readmission following TKA, and to determine the effect size of the association between these risk factors and unplanned 30-day readmission. We searched MEDLINE and EMBASE from inception to 8 September 2020 for English language articles. Reference lists of included articles were searched for additional literature. Patients of interest were TKA recipients (primary and revision) compared for 30-day readmission to any institution, due to any cause, based on patient risk factors; case series were excluded. Two reviewers independently extracted data and carried out critical appraisal. In-hospital complications during the index admission were the strongest risk factors for 30-day readmission in both primary and revision TKA patients, suggesting discharge planning to include closer post-discharge monitoring to prevent avoidable readmission may be warranted. Further research could determine whether closer monitoring post-discharge would prevent unplanned but avoidable readmissions. Increased comorbidity burden correlated with increased risk, as did specific comorbidities. Body mass index was not strongly correlated with readmission risk. Demographic risk factors included low socioeconomic status, but the impact of age on readmission risk was less clear. These risk factors can also be included in predictive models for 30-day readmission in TKA patients to identify high-risk patients as part of risk reduction programs.

Geospatial analysis of the urban and rural/remote distribution of dental services in Scotland, Wales and Northern Ireland.

AIM: To address deficits in human resources for oral health data (HROH) in rural and remote areas in Wales, Scotland and Northern Ireland by spatially profiling and modelling the distribution pattern of dental practices according to Health Boards. METHODS: National Health Service (NHS) dental practices were located and mapped against population and rural-urban classifications of Scotland, Wales and Northern Ireland, using Geographic Information System (GIS) tools. All data collected were at the smallest geographical statistical hierarchy level in each country, and population data were retrieved from the 2011 census. RESULTS: A total of 1,695 NHS dental practices were mapped against 27 Health Board regions. In Scotland, Northern Ireland and Wales, 18.3%, 18.7% and 7.7%, respectively, of the population living in the most remote areas resided within 2.5 km of a dental practice. In each country, the Health Boards with the largest proportion of the population living more than 10 km from a dental practice were the Western Isles (Scotland), Western Health and Social Care Trust (HSCT) (Northern Ireland) and Hywel Dda University Health Board (UHB) (Wales). In each country, the highest practice-to-population (PtP) ratios were found in Forth Valley (1:7,194) (Scotland), Southern HSCT (1:5,115) (Northern Ireland) and Hywel Dda UHB (Wales) (1:7,907). CONCLUSION: Dental services are distributed unequally between urban and rural areas. PtP ratios coupled with GIS analysis are important tools to improve HROH distribution.

Are NHS dental practices socioeconomically distributed in Scotland, Wales and Northern Ireland?

Aim To investigate the relationship between deprivation and distance to NHS dental providers in Scotland, Wales and Northern Ireland.Methods A total of 1,795 NHS dental practices were located at the smallest geographic areas for Scotland, Wales and Northern Ireland. A geographic information system (GIS) was used to overlay the distribution of dental practices with areas graded by the Index of Multiple Deprivation (IMD) and population census from 2011.Results In Scotland, Wales and Northern Ireland, 15%, 17.8% and 27.5% of the population lived outside 2.5 km of an NHS dental practice, respectively. NHS dental clinics were distributed mostly among people that lived in IMD 1 and 5 areas across the respective deprivation measures of all three nations. There were negligible differences in area-based deprivation measures and NHS dental clinic distribution.Conclusion NHS dental practices in Scotland, Wales and Northern Ireland were not socioeconomically distributed, suggesting an equitable spatial availability of services based on need.

The role of Thallium-201 scintigraphy and Tc-99m pentavalent dimercaptosuccinic acid in diagnosis and grading of chondrosarcoma.

PURPOSE: Distinguishing between enchondromas and low-grade (grade 1) chondrosarcomas can be challenging. The aim of this study was to investigate the role of Thallium-201 scintigraphy and Technetium-99 m pentavalent dimercaptosuccinic acid (Tc-99 m DMSA (V)) in the diagnosis and grading of chondrosarcomas. METHODS: 232 consecutive patients with pathologically proven cartilaginous tumours between the years 2000 and 2018 were evaluated. We included 197 patients (101 males and 96 females; median age 50 years; range 15-86 years) who underwent Thallium-201(n = 193) and/or Tc-99 m DMSA (V) scanning (n = 67). Increased uptake was defined as uptake greater than background. The reference standard was the histopathological assessment based on a grading system (grade 1-3). Data was analysed using multivariate modelling. RESULTS: There were 46 patients with enchondromas and 151 with chondrosarcomas. Of those, 64 (enchondroma n = 21, chondrosarcoma n = 43) underwent both Thallium-201 and Tc-99 m DMSA (V). Thallium-201 uptake had 7.92 times greater odds of grade 1 chondrosarcomas than enchondromas. Thallium-201 uptake was significantly associated with the odds of a higher grade chondrosarcoma (grade 2-3). DMSA (V) positivity was associated with 4.75 times the odds of a chondrosarcoma diagnosis over enchondroma (p = 0.024). DMSA (V) uptake revealed no association with chondrosarcoma grading. CONCLUSION: Low-grade chondrosarcomas continue to pose a diagnostic dilemma. Thallium-201 scans may identify malignancy in benign appearing tumours as well as differentiate between low-grade and high-grade chondrosarcomas in said malignancies. DMSA (V) may be useful in distinguishing between benign and malignant entities as a whole.