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Bone & Joint Research
Vol. 8, Issue 6 | Pages 275 - 287
1 Jun 2019
Clement ND Bardgett M Merrie K Furtado S Bowman R Langton DJ Deehan DJ Holland J

Objectives

Our primary aim was to describe migration of the Exeter stem with a 32 mm head on highly crosslinked polyethylene and whether this is influenced by age. Our secondary aims were to assess functional outcome, satisfaction, activity, and bone mineral density (BMD) according to age.

Patients and Methods

A prospective cohort study was conducted. Patients were recruited into three age groups: less than 65 years (n = 65), 65 to 74 years (n = 68), and 75 years and older (n = 67). There were 200 patients enrolled in the study, of whom 115 were female and 85 were male, with a mean age of 69.9 years (sd 9.5, 42 to 92). They were assessed preoperatively, and at three, 12 and, 24 months postoperatively. Stem migration was assessed using Einzel-Bild-Röntgen-Analyse (EBRA). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), Hip Disability and Osteoarthritis Outcome Score (HOOS), EuroQol-5 domains questionnaire (EQ-5D), short form-36 questionnaire (SF-36,) and patient satisfaction were used to assess outcome. The Lower Extremity Activity Scale (LEAS), Timed Up and Go (TUG) test, and activPAL monitor (energy expelled, time lying/standing/walking and step count) were used to assess activity. The BMD was assessed in Gruen and Charnley zones.


Bone & Joint 360
Vol. 7, Issue 5 | Pages 13 - 16
1 Oct 2018


The Bone & Joint Journal
Vol. 100-B, Issue 9 | Pages 1175 - 1181
1 Sep 2018
Benca E Willegger M Wenzel F Hirtler L Zandieh S Windhager R Schuh R

Aims

The traditional transosseus flexor hallucis longus (FHL) tendon transfer for patients with Achilles tendinopathy requires two incisions to harvest a long tendon graft. The use of a bio-tenodesis screw enables a short graft to be used and is less invasive, but lacks supporting evidence about its biomechanical behaviour. We aimed, in this study, to compare the strength of the traditional transosseus tendon-to-tendon fixation with tendon-to-bone fixation using a tenodesis screw, in cyclical loading and ultimate load testing.

Materials and Methods

Tendon grafts were undertaken in 24 paired lower-leg specimens and randomly assigned in two groups using fixation with a transosseus suture (suture group) or a tenodesis screw (screw group). The biomechanical behaviour was evaluated using cyclical and ultimate loading tests. The Student’s t-test was performed to assess statistically significant differences in bone mineral density (BMD), displacement, the slope of the load-displacement curves, and load to failure.


Bone & Joint 360
Vol. 7, Issue 1 | Pages 22 - 24
1 Feb 2018


Bone & Joint Research
Vol. 7, Issue 4 | Pages 274 - 281
1 Apr 2018
Collins KH Hart DA Seerattan RA Reimer RA Herzog W

Objectives

Metabolic syndrome and low-grade systemic inflammation are associated with knee osteoarthritis (OA), but the relationships between these factors and OA in other synovial joints are unclear. The aim of this study was to determine if a high-fat/high-sucrose (HFS) diet results in OA-like joint damage in the shoulders, knees, and hips of rats after induction of obesity, and to identify potential joint-specific risks for OA-like changes.

Methods

A total of 16 male Sprague-Dawley rats were allocated to either the diet-induced obesity group (DIO, 40% fat, 45% sucrose, n = 9) or a chow control diet (n = 7) for 12 weeks. At sacrifice, histological assessments of the shoulder, hip, and knee joints were performed. Serum inflammatory mediators and body composition were also evaluated. The total Mankin score for each animal was assessed by adding together the individual Modified Mankin scores across all three joints. Linear regression modelling was conducted to evaluate predictive relationships between serum mediators and total joint damage.


Bone & Joint Research
Vol. 7, Issue 1 | Pages 6 - 11
1 Jan 2018
Wong RMY Choy MHV Li MCM Leung K K-H. Chow S Cheung W Cheng JCY

Objectives

The treatment of osteoporotic fractures is a major challenge, and the enhancement of healing is critical as a major goal in modern fracture management. Most osteoporotic fractures occur at the metaphyseal bone region but few models exist and the healing is still poorly understood. A systematic review was conducted to identify and analyse the appropriateness of current osteoporotic metaphyseal fracture animal models.

Materials and Methods

A literature search was performed on the Pubmed, Embase, and Web of Science databases, and relevant articles were selected. A total of 19 studies were included. Information on the animal, induction of osteoporosis, fracture technique, site and fixation, healing results, and utility of the model were extracted.


Bone & Joint Research
Vol. 5, Issue 9 | Pages 362 - 369
1 Sep 2016
Oba M Inaba Y Kobayashi N Ike H Tezuka T Saito T

Objectives

In total hip arthroplasty (THA), the cementless, tapered-wedge stem design contributes to achieving initial stability and providing optimal load transfer in the proximal femur. However, loading conditions on the femur following THA are also influenced by femoral structure. Therefore, we determined the effects of tapered-wedge stems on the load distribution of the femur using subject-specific finite element models of femurs with various canal shapes.

Patients and Methods

We studied 20 femurs, including seven champagne flute-type femurs, five stovepipe-type femurs, and eight intermediate-type femurs, in patients who had undergone cementless THA using the Accolade TMZF stem at our institution. Subject–specific finite element (FE) models of pre- and post-operative femurs with stems were constructed and used to perform FE analyses (FEAs) to simulate single-leg stance. FEA predictions were compared with changes in bone mineral density (BMD) measured for each patient during the first post-operative year.


Bone & Joint Research
Vol. 5, Issue 9 | Pages 419 - 426
1 Sep 2016
Leichtle CI Lorenz A Rothstock S Happel J Walter F Shiozawa T Leichtle UG

Objectives

Cement augmentation of pedicle screws could be used to improve screw stability, especially in osteoporotic vertebrae. However, little is known concerning the influence of different screw types and amount of cement applied. Therefore, the aim of this biomechanical in vitro study was to evaluate the effect of cement augmentation on the screw pull-out force in osteoporotic vertebrae, comparing different pedicle screws (solid and fenestrated) and cement volumes (0 mL, 1 mL or 3 mL).

Materials and Methods

A total of 54 osteoporotic human cadaver thoracic and lumbar vertebrae were instrumented with pedicle screws (uncemented, solid cemented or fenestrated cemented) and augmented with high-viscosity PMMA cement (0 mL, 1 mL or 3 mL). The insertion torque and bone mineral density were determined. Radiographs and CT scans were undertaken to evaluate cement distribution and cement leakage. Pull-out testing was performed with a material testing machine to measure failure load and stiffness. The paired t-test was used to compare the two screws within each vertebra.


The Bone & Joint Journal
Vol. 99-B, Issue 3 | Pages 291 - 294
1 Mar 2017
Javaid MK Handley R Costa ML


The Bone & Joint Journal
Vol. 97-B, Issue 8 | Pages 1106 - 1110
1 Aug 2015
Kherad M Mellström D Rosengren BE Hasserius R Nilsson J Redlund-Johnell I Ohlsson C Lorentzon M Karlsson MK

We sought to determine whether specific characteristics of vertebral fractures in elderly men are associated with low bone mineral density (BMD) and osteoporosis.

Mister osteoporosis Sweden is a population based cohort study involving 3014 men aged 69 to 81 years. Of these, 1427 had readable lateral radiographs of the thoracic and lumbar spine. Total body (TB) BMD (g/cm²) and total right hip (TH) BMD were measured by dual energy x-ray absorptiometry. The proportion of men with osteoporosis was calculated from TH BMD. There were 215 men (15.1%) with a vertebral fracture. Those with a fracture had lower TB BMD than those without (p < 0.001). Among men with a fracture, TB BMD was lower in those with more than three fractures (p = 0.02), those with biconcave fractures (p = 0.02) and those with vertebral body compression of > 42% (worst quartile) (p = 0.03). The mean odds ratio (OR) for having osteoporosis when having any type of vertebral fracture was 6.1 (95% confidence interval (CI) 3.9 to 9.5) compared with those without a fracture. A combination of more than three fractures and compression in the worst quartile had a mean OR of 114.2 (95% CI 6.7 to 1938.3) of having osteoporosis compared with those without a fracture.

We recommend BMD studies to be undertaken in these subcohorts of elderly men with a vertebral fracture.

Cite this article: 2015;97-B:1106–10.


Bone & Joint Research
Vol. 5, Issue 11 | Pages 544 - 551
1 Nov 2016
Kim Y Bok DH Chang H Kim SW Park MS Oh JK Kim J Kim T

Objectives

Although vertebroplasty is very effective for relieving acute pain from an osteoporotic vertebral compression fracture, not all patients who undergo vertebroplasty receive the same degree of benefit from the procedure. In order to identify the ideal candidate for vertebroplasty, pre-operative prognostic demographic or clinico-radiological factors need to be identified. The objective of this study was to identify the pre-operative prognostic factors related to the effect of vertebroplasty on acute pain control using a cohort of surgically and non-surgically managed patients.

Patients and Methods

Patients with single-level acute osteoporotic vertebral compression fracture at thoracolumbar junction (T10 to L2) were followed. If the patients were not satisfied with acute pain reduction after a three-week conservative treatment, vertebroplasty was recommended. Pain assessment was carried out at the time of diagnosis, as well as three, four, six, and 12 weeks after the diagnosis. The effect of vertebroplasty, compared with conservative treatment, on back pain (visual analogue score, VAS) was analysed with the use of analysis-of-covariance models that adjusted for pre-operative VAS scores.


The Bone & Joint Journal
Vol. 98-B, Issue 6 | Pages 840 - 845
1 Jun 2016
Chesser TJS Fox R Harding K Halliday R Barnfield S Willett K Lamb S Yau C Javaid MK Gray AC Young J Taylor H Shah K Greenwood R

Aims

We wished to assess the feasibility of a future randomised controlled trial of parathyroid hormone (PTH) supplements to aid healing of trochanteric fractures of the hip, by an open label prospective feasibility and pilot study with a nested qualitative sub study. This aimed to inform the design of a future powered study comparing the functional recovery after trochanteric hip fracture in patients undergoing standard care, versus those who undergo administration of subcutaneous injection of PTH for six weeks.

Patients and Methods

We undertook a pilot study comparing the functional recovery after trochanteric hip fracture in patients 60 years or older, admitted with a trochanteric hip fracture, and potentially eligible to be randomised to either standard care or the administration of subcutaneous PTH for six weeks. Our desired outcomes were functional testing and measures to assess the feasibility and acceptability of the study.


Bone & Joint Research
Vol. 1, Issue 2 | Pages 13 - 19
1 Feb 2012
Smith MD Baldassarri S Anez-Bustillos L Tseng A Entezari V Zurakowski D Snyder BD Nazarian A

Objectives

This study aims to assess the correlation of CT-based structural rigidity analysis with mechanically determined axial rigidity in normal and metabolically diseased rat bone.

Methods

A total of 30 rats were divided equally into normal, ovariectomized, and partially nephrectomized groups. Cortical and trabecular bone segments from each animal underwent micro-CT to assess their average and minimum axial rigidities using structural rigidity analysis. Following imaging, all specimens were subjected to uniaxial compression and assessment of mechanically-derived axial rigidity.


The Bone & Joint Journal
Vol. 96-B, Issue 7 | Pages 896 - 901
1 Jul 2014
Reiner T Jaeger S Schwarze M Klotz MC Beckmann NA Bitsch RG

Aseptic loosening of the femoral component is an important indication for revision surgery in unicompartmental knee replacement (UKR). A new design of femoral component with an additional peg was introduced for the cemented Oxford UKR to increase its stability. The purpose of this study was to compare the primary stability of the two designs of component.

Medial Oxford UKR was performed in 12 pairs of human cadaver knees. In each pair, one knee received the single peg and one received the twin peg design. Three dimensional micromotion and subsidence of the component in relation to the bone was measured under cyclical loading at flexion of 40° and 70° using an optical measuring system. Wilcoxon matched pairs signed-rank test was performed to detect differences between the two groups.

There was no significant difference in the relative micromotion (p = 0.791 and 0.380, respectively) and subsidence (p = 0.301 and 0.176, respectively) of the component between the two groups at both angles of flexion. Both designs of component offered good strength of fixation in this cadaver study.

Cite this article: Bone Joint J 2014;96-B:896–901.


The Bone & Joint Journal
Vol. 96-B, Issue 11 | Pages 1503 - 1509
1 Nov 2014
Ritter MA Davis KE Small SR Merchun JG Farris A

The relationship between post-operative bone density and subsequent failure of total knee replacement (TKR) is not known. This retrospective study aimed to determine the relationship between bone density and failure, both overall and according to failure mechanism. All 54 aseptic failures occurring in 50 patients from 7760 consecutive primary cemented TKRs between 1983 and 2004 were matched with non-failing TKRs, and 47 failures in 44 patients involved tibial failures with the matching characteristics of age (65.1 for failed and 69.8 for non-failed), gender (70.2% female), diagnosis (93.6% OA), date of operation, bilaterality, pre-operative alignment (0.4 and 0.3 respectively), and body mass index (30.2 and 30.0 respectively). In each case, the density of bone beneath the tibial component was assessed at each follow-up interval using standardised, calibrated radiographs. Failing knees were compared with controls both overall and, as a subgroup analysis, by failure mechanism. Knees were compared with controls using univariable linear regression.

Significant and continuous elevation in tibial density was found in knees that eventually failed by medial collapse (p < 0.001) and progressive radiolucency (p < 0.001) compared with controls, particularly in the medial region of the tibia. Knees failing due to ligamentous instability demonstrated an initial decline in density (p = 0.0152) followed by a non-decreasing density over time (p = 0.034 for equivalence). Non-failing knees reported a decline in density similar to that reported previously using dual-energy x-ray absorptiometry (DEXA). Differences between failing and non-failing knees were observable as early as two months following surgery. This tool may be used to identify patients at risk of failure following TKR, but more validation work is needed.

Cite this article: Bone Joint J 2014;96-B:1503–9.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 11 | Pages 1509 - 1514
1 Nov 2010
Smolders JMH Hol A Rijnders T van Susante JLC

We undertook a randomised prospective follow-up study of changes in peri-prosthetic bone mineral density (BMD) after hip resurfacing and compared them with the results after total hip replacement. A total of 59 patients were allocated to receive a hip resurfacing (n = 29) or an uncemented distally fixed total hip replacement (n = 30). The BMD was prospectively determined in four separate regions of interest of the femoral neck and in the calcar region corresponding to Gruen zone 7 for the hip resurfacing group and compared only to the calcar region in the total hip replacement group. Standardised measurements were performed pre-operatively and after three, six and 12 months. The groups were well matched in terms of gender distribution and mean age.

The mean BMD in the calcar region increased after one year to 105.2% of baseline levels in the resurfaced group compared with a significant decrease to 82.1% in the total hip replacement group (p < 0.001) by 12 months. For the resurfaced group, there was a decrease in bone density in all four regions of the femoral neck at three months which did not reach statistical significance and was followed by recovery to baseline levels after 12 months.

Hip resurfacing did indeed preserve BMD in the inferior femoral neck. In contrast, a decrease in the mean BMD in Gruen zone 7 followed uncemented distally fixed total hip replacement. Long term follow-up studies are necessary to see whether this benefit in preservation of BMD will be clinically relevant at future revision surgery.


Bone & Joint 360
Vol. 2, Issue 6 | Pages 34 - 36
1 Dec 2013

The December 2013 Research Roundup360 looks at: Inflammation implicated in FAI; Ponseti and effective teaching; Unicompartmental knee design and tibial strain; Bisphosphonates and fracture healing; Antibiosis in cement; Zoledronic acid improves primary stability in revision?; Osteoporotic fractures revisited; and electroarthrography for monitoring of cartilage degeneration


The Bone & Joint Journal
Vol. 95-B, Issue 9 | Pages 1250 - 1254
1 Sep 2013
Lakstein D Hendel D Haimovich Y Feldbrin Z

The purpose of this study was to identify changing trends in the pattern of distribution of the type and demographics of fractures of the hip in the elderly between 2001 and 2010. A retrospective cross-sectional comparison was conducted between 179 fractures of the hip treated in 2001, 357 treated in 2006 and 454 treated in 2010. Patients aged < 60 years and those with pathological and peri-prosthetic fractures were excluded. Fractures were classified as stable extracapsular, unstable extracapsular or intracapsular fractures.

The mean age of the 179 patients (132 women (73.7%)) treated in 2001 was 80.8 years (60 to 96), 81.8 years (61 to 101) in the 357 patients (251 women (70.3%)) treated in 2006 and 82.0 years (61 to 102) in the 454 patients (321 women (70.1%)) treated in 2010 (p = 0.17). There was no difference in the gender distribution between the three study years (p = 0.68).

The main finding was a steep rise in the proportion of unstable peritrochanteric fractures. The proportion of unstable extracapsular fractures was 32% (n = 57) in 2001, 35% (n = 125) in 2006 and 45% (n = 204) in 2010 (p < 0.001). This increase was not significant in patients aged between 60 and 69 years (p = 0.84), marginally significant in those aged between 70 and 79 years (p = 0.04) and very significant in those aged > 80 years (p < 0.001). The proportion of intracapsular fractures did not change (p = 0.94).

At present, we face not only an increasing number of fractures of the hip, but more demanding and complex fractures in older patients than a decade ago. This study does not provide an explanation for this change.

Cite this article: Bone Joint J 2013;95-B:1250–4.


Bone & Joint 360
Vol. 2, Issue 3 | Pages 18 - 20
1 Jun 2013

The June 2013 Hip & Pelvis Roundup360 looks at: failure in metal-on-metal arthroplasty; minimal hip approaches; whether bisphosphonates improve femoral bone stock following arthroplasty; whether more fat means more operative time; surgical infection; vascularised fibular graft for osteonecrosis; subclinical SUFE; and dentists, hips and antibiotics.


The Bone & Joint Journal
Vol. 96-B, Issue 1 | Pages 114 - 121
1 Jan 2014
Pekmezci M McDonald E Buckley J Kandemir U

We investigated a new intramedullary locking nail that allows the distal interlocking screws to be locked to the nail. We compared fixation using this new implant with fixation using either a conventional nail or a locking plate in a laboratory simulation of an osteoporotic fracture of the distal femur. A total of 15 human cadaver femora were used to simulate an AO 33-A3 fracture pattern. Paired specimens compared fixation using either a locking or non-locking retrograde nail, and using either a locking retrograde nail or a locking plate. The constructs underwent cyclical loading to simulate single-leg stance up to 125 000 cycles. Axial and torsional stiffness and displacement, cycles to failure and modes of failure were recorded for each specimen. When compared with locking plate constructs, locking nail constructs had significantly longer mean fatigue life (75 800 cycles (sd 33 900) vs 12 800 cycles (sd 6100); p = 0.007) and mean axial stiffness (220 N/mm (sd 80) vs 70 N/mm (sd 18); p = 0.005), but lower mean torsional stiffness (2.5 Nm/° (sd 0.9) vs 5.1 Nm/° (sd 1.5); p = 0.008). In addition, in the nail group the mode of failure was either cut-out of the distal screws or breakage of nails, and in the locking plate group breakage of the plate was always the mode of failure. Locking nail constructs had significantly longer mean fatigue life than non-locking nail constructs (78 900 cycles (sd 25 600) vs 52 400 cycles (sd 22 500); p = 0.04).

The new locking retrograde femoral nail showed better stiffness and fatigue life than locking plates, and superior fatigue life to non-locking nails, which may be advantageous in elderly patients.

Cite this article: Bone Joint J 2014;96-B:114–21.