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Bone & Joint Research
Vol. 10, Issue 2 | Pages 105 - 112
1 Feb 2021
Feng X Qi W Fang CX Lu WW Leung FKL Chen B

Aims

To draw a comparison of the pullout strengths of buttress thread, barb thread, and reverse buttress thread bone screws.

Methods

Buttress thread, barb thread, and reverse buttress thread bone screws were inserted into synthetic cancellous bone blocks. Five screw-block constructs per group were tested to failure in an axial pullout test. The pullout strengths were calculated and compared. A finite element analysis (FEA) was performed to explore the underlying failure mechanisms. FEA models of the three different screw-bone constructs were developed. A pullout force of 250 N was applied to the screw head with a fixed bone model. The compressive and tensile strain contours of the midsagittal plane of the three bone models were plotted and compared.


Bone & Joint 360
Vol. 10, Issue 5 | Pages 32 - 35
1 Oct 2021


The Journal of Bone & Joint Surgery British Volume
Vol. 71-B, Issue 5 | Pages 774 - 776
1 Nov 1989
Spencer R

Retrospective review of 25 patients over 65 years of age with unilateral acetabular fractures managed conservatively showed that seven of the 23 survivors (30%) had an unacceptable functional result. Poor results were associated with: displaced posterior column fractures, osteoporosis, femoral head fracture, delayed diagnosis, inadequate radiographs, inappropriate or too brief traction, and early weight-bearing. In this age group acetabular fractures tend to be low-velocity injuries of osteoporotic bone and are not comparable with those in younger patients


Bone & Joint Research
Vol. 10, Issue 1 | Pages 41 - 50
1 Jan 2021
Wong RMY Choy VMH Li J Li TK Chim YN Li MCM Cheng JCY Leung K Chow SK Cheung WH

Aims

Fibrinolysis plays a key transition step from haematoma formation to angiogenesis and fracture healing. Low-magnitude high-frequency vibration (LMHFV) is a non-invasive biophysical modality proven to enhance fibrinolytic factors. This study investigates the effect of LMHFV on fibrinolysis in a clinically relevant animal model to accelerate osteoporotic fracture healing.

Methods

A total of 144 rats were randomized to four groups: sham control; sham and LMHFV; ovariectomized (OVX); and ovariectomized and LMHFV (OVX-VT). Fibrinolytic potential was evaluated by quantifying fibrin, tissue plasminogen activator (tPA), and plasminogen activator inhibitor-1 (PAI-1) along with healing outcomes at three days, one week, two weeks, and six weeks post-fracture.


Bone & Joint 360
Vol. 10, Issue 4 | Pages 37 - 40
1 Aug 2021


The Journal of Bone & Joint Surgery British Volume
Vol. 77-B, Issue 5 | Pages 733 - 735
1 Sep 1995
Fraser R Dickens D Cole W

We report the results of medial physeal stapling in 16 knees with primary genu valgum and 27 with secondary genu valgum. In the primary group, stapling was undertaken at a mean chronological age of 12 years in girls and 13 years in boys. The medial femoral physis was stapled in ten knees and the medial femoral and tibial physes in six knees. At skeletal maturity, all patients had excellent or good leg alignment. Secondary genu valgum is due to skeletal dysplasia, haematological or endocrine disorders, or to juvenile chronic arthritis. Stapling was at a mean chronological age of 11 years in girls and 14 years in boys. The medial femoral physis was stapled in 13 knees, the medial tibial physis in three and both in 11 knees. At skeletal maturity, 85% had excellent or good leg alignment, and correction had occurred within one year. Two of the poor results were due to staple extrusion from osteoporotic bone, and two to overcorrection. Rebound growth was minimal and unpredictable after the removal of staples. Medial physeal stapling is a suitable method of treatment for both primary and secondary genu valgum in late childhood and in adolescence. At least one year of knee growth is required to achieve correction, and care is needed to avoid overcorrection of the secondary genu valgum


The Bone & Joint Journal
Vol. 103-B, Issue 1 | Pages 71 - 78
1 Jan 2021
Maggs JL Swanton E Whitehouse SL Howell JR Timperley AJ Hubble MJW Wilson MJ

Aims

Periprosthetic fractures (PPFs) around cemented taper-slip femoral prostheses often result in a femoral component that is loose at the prosthesis-cement interface, but where the cement-bone interface remains well-fixed and bone stock is good. We aim to understand how best to classify and manage these fractures by using a modification of the Vancouver classification.

Methods

We reviewed 87 PPFs. Each was a first episode of fracture around a cemented femoral component, where surgical management consisted of revision surgery. Data regarding initial injury, intraoperative findings, and management were prospectively collected. Patient records and serial radiographs were reviewed to determine fracture classification, whether the bone cement was well fixed (B2W) or loose (B2L), and time to fracture union following treatment.


The Bone & Joint Journal
Vol. 102-B, Issue 12 | Pages 1629 - 1635
1 Dec 2020
Wang Q Sheng N Rui B Chen Y

Aims

The aim of this study was to explore why some calcar screws are malpositioned when a proximal humeral fracture is treated by internal fixation with a locking plate, and to identify risk factors for this phenomenon. Some suggestions can be made of ways to avoid this error.

Methods

We retrospectively identified all proximal humeral fractures treated in our institution between October 2016 and October 2018 using the hospital information system. The patients’ medical and radiological data were collected, and we divided potential risk factors into two groups: preoperative factors and intraoperative factors. Preoperative factors included age, sex, height, weight, body mass index, proximal humeral bone mineral density, type of fracture, the condition of the medial hinge, and medial metaphyseal head extension. Intraoperative factors included the grade of surgeon, neck-shaft angle after reduction, humeral head height, restoration of medial support, and quality of reduction. Adjusted binary logistic regression and multivariate logistic regression models were used to identify pre- and intraoperative risk factors. Area under the curve (AUC) analysis was used to evaluate the discriminative ability of the multivariable model.


The Journal of Bone & Joint Surgery British Volume
Vol. 44-B, Issue 3 | Pages 464 - 484
1 Aug 1962
Urist MR Zaccalini PS MacDonald NS Skoog WA

1. Individuals who are normal and not osteoporotic seem to show retention of cortical bone at successive decades of life in proportion to the total lean body-mass. In patients with osteoporosis the weight of the skeleton decreases at a rate exceeding the physiological rate of atrophy of muscle, tendon and bone tissue that occurs with the time-dependent process of ageing. 2. Six patients representing the typical forms of osteoporosis commonly found in orthopaedic practice were investigated intensively over a period of three years and compared with individuals in whom there was no osteoporosis by studies of metabolic balance, Sr85 osteograms, and tetracycline deposition. 3. Studies of metabolic balance in patients with osteoporosis showed normal or negative calcium balances, but an equilibrium for the metabolism of nitrogen and phosphorus. Increased intake of calcium in the diet produced retention of calcium but not sufficient phosphorus, nitrogen or gain in weight to prove that the patient had made new bone and healed the osteoporosis. 4. Radio-isotope osteograms showed high, normal or low rates of change of uptake of Sr85 and the accretion rate was calculated to be normal or low in individuals with osteoporosis. High uptake of tetracycline by a small mass of bone tissue and by a relatively small percentage of the total number of osteons suggested that in an adult human being the calcium reserve in the skeleton is enormous. Thirty to 50 per cent of the total bone mass was sufficient to turn over 0·5 to 1·0 gramme, the amount of calcium utilised in twenty-four hours by the human adult. This was accomplished by structural or old bone throughout the entire skeleton, and by labile or newer bone located in approximately 10 per cent of the total number of Haversian cylinders or osteons. 5. Some of the unclosed or half-closed osteons were hyperactive in osteoporotic bones. In the process of remodelling of cortical bone a significant quantity of bone tissue was incompletely restored and there were, presumably as a result, intermittently large or small negative calcium balances. Osteoporosis may have been the cause, rather than the result, of the negative calcium balance. 6. The experimental and clinical literature of the past ten years, and studies on patients described in this critical review, were interpreted to indicate that prolonged calcium deficiency, castration, hyperadrenal corticoidism or a sedentary life may precipitate, accentuate and accelerate osteoporosis in individuals who are genetically predisposed to develop it. Sometimes high calcium intake or sex hormones, or both, may have slowed the rate of resorption but did not replace the deficit in cortical bone. 7. Further research is necessary to find the chief etiological factor and to produce the cure for this increasingly common disorder of the skeleton


The Journal of Bone & Joint Surgery British Volume
Vol. 43-B, Issue 2 | Pages 346 - 361
1 May 1961
Caldwell RA Collins DH

1. Radiological, chemical and histological examinations have been made of the lumbar vertebral bodies in 100 necropsies on patients dying in a general hospital, with a view to determining the range of variation of calcium content and radiographic density in normal and osteoporotic bone. 2. Radiographs were made of sagittal mid-line vertebral body slabs uniformly one centimetre in thickness, and the radiographic density of these specimens was measured in relation to an aluminium step-wedge of one to ten units. Radio-opacity of different vertebrae ranged from four to ten units. The specimen radiographs also clearly revealed the trabecular structure and the lateral profile of the bones. 3. Calcium was chemically estimated and expressed as weight of the element per unit volume of the whole bone mass (that is, of anatomical bone including soft marrow tissue). It ranged from 38 to 102 milligrams per cubic centimetre of bone. In 75 per cent of the cases the range was 50-84 milligrams per cubic centimetre. High calcium values were mostly encountered in young adults, and the calcium per unit volume tended to diminish with age; but a wide range of calcium was still encountered in the older subjects and a better correlation with age was achieved by radiographic density. Both calcium content and radiographic density tended to be higher in the male than in the female bones at all ages. 4. The results of both calcium and radiographic density showed a smooth distribution curve, though skewed through the inclusion in the series of more older people with less mineralised bones; the absence of a double peak in these curves suggests that the examinations were made on a homogeneous population and does not indicate a separate pathological group of osteoporotic subjects. 5. Arbitrary standards must be used to distinguish osteoporotic from normal bones, since neither radiological measurement or chemical assay, nor histological assessment, reveals a point at which the two groups can be separated. In the present series it seemed to us satisfactory to regard as abnormal all bones showing a radiographic density of five or less step-wedge units, and by this standard nineteen of the 100 cases (eight male, eleven female) were deemed to be osteoporotic. Histological examination excluded other forms of bone rarefaction. 6. The regression of calcium on the density measurements proved to be statistically significant and was not affected either by age or by the number of days in bed during the last illness. A small difference between the sexes was apparent, there being slightly less calcium in female than in male bones of equal radiographic density. Provided this is taken into account, the radiographic density scale can be used to predict the calcium content of vertebral bone specimens and should prove a rapid and accurate method in a survey of osteoporosis in post-mortem room material


The Bone & Joint Journal
Vol. 102-B, Issue 11 | Pages 1475 - 1483
7 Nov 2020
Oliver WM Searle HKC Ng ZH Wickramasinghe NRL Molyneux SG White TO Clement ND Duckworth AD

Aims

The aim of this study was to determine the current incidence and epidemiology of humeral diaphyseal fractures. The secondary aim was to explore variation in patient and injury characteristics by fracture location within the humeral diaphysis.

Methods

Over ten years (2008 to 2017), all adult patients (aged ≥ 16 years) sustaining an acute fracture of the humeral diaphysis managed at the study centre were retrospectively identified from a trauma database. Patient age, sex, medical/social background, injury mechanism, fracture classification, and associated injuries were recorded and analyzed.


Bone & Joint 360
Vol. 9, Issue 5 | Pages 4 - 9
1 Oct 2020
Matthews E Waterson HB Phillips JR Toms AD


The Bone & Joint Journal
Vol. 103-B, Issue 2 | Pages 294 - 298
1 Feb 2021
Hadeed MM Prakash H Yarboro SR Weiss DB

Aims

The aim of this study was to determine the immediate post-fixation stability of a distal tibial fracture fixed with an intramedullary nail using a biomechanical model. This was used as a surrogate for immediate weight-bearing postoperatively. The goal was to help inform postoperative protocols.

Methods

A biomechanical model of distal metaphyseal tibial fractures was created using a fourth-generation composite bone model. Three fracture patterns were tested: spiral, oblique, and multifragmented. Each fracture extended to within 4 cm to 5 cm of the plafond. The models were nearly-anatomically reduced and stabilized with an intramedullary nail and three distal locking screws. Cyclic loading was performed to simulate normal gait. Loading was completed in compression at 3,000 N at 1 Hz for a total of 70,000 cycles. Displacement (shortening, coronal and sagittal angulation) was measured at regular intervals.


Bone & Joint 360
Vol. 10, Issue 1 | Pages 28 - 31
1 Feb 2021


Bone & Joint 360
Vol. 9, Issue 3 | Pages 11 - 14
1 Jun 2020


Bone & Joint Research
Vol. 9, Issue 6 | Pages 314 - 321
1 Jun 2020
Bliven E Sandriesser S Augat P von Rüden C Hackl S

Aims

Evaluate if treating an unstable femoral neck fracture with a locking plate and spring-loaded telescoping screw system would improve construct stability compared to gold standard treatment methods.

Methods

A 31B2 Pauwels’ type III osteotomy with additional posterior wedge was cut into 30 fresh-frozen femur cadavers implanted with either: three cannulated screws in an inverted triangle configuration (CS), a sliding hip screw and anti-rotation screw (SHS), or a locking plate system with spring-loaded telescoping screws (LP). Dynamic cyclic compressive testing representative of walking with increasing weight-bearing was applied until failure was observed. Loss of fracture reduction was recorded using a high-resolution optical motion tracking system.


Bone & Joint 360
Vol. 9, Issue 2 | Pages 3 - 6
1 Apr 2020
Myint Y Ollivere B


The Bone & Joint Journal
Vol. 102-B, Issue 2 | Pages 155 - 161
1 Feb 2020
McMahon SE Diamond OJ Cusick LA

Aims

Complex displaced osteoporotic acetabular fractures in the elderly are associated with high levels of morbidity and mortality. Surgical options include either open reduction and internal fixation alone, or combined with total hip arthroplasty (THA). There remains a cohort of severely comorbid patients who are deemed unfit for extensive surgical reconstruction and are treated conservatively. We describe the results of a coned hemipelvis reconstruction and THA inserted via a posterior approach to the hip as the primary treatment for this severely high-risk cohort.

Methods

We have prospectively monitored a series of 22 cases (21 patients) with a mean follow-up of 32 months (13 to 59).


Bone & Joint 360
Vol. 8, Issue 6 | Pages 15 - 18
1 Dec 2019


The Bone & Joint Journal
Vol. 102-B, Issue 1 | Pages 33 - 41
1 Jan 2020
Norman JG Brealey S Keding A Torgerson D Rangan A

Aims

The aim of this study was to explore whether time to surgery affects functional outcome in displaced proximal humeral fractures

Methods

A total of 250 patients presenting within three weeks of sustaining a displaced proximal humeral fracture involving the surgical neck were recruited at 32 acute NHS hospitals in the United Kingdom between September 2008 and April 2011. Of the 125 participants, 109 received surgery (fracture fixation or humeral head replacement) as per randomization. Data were included for 101 and 67 participants at six-month and five-year follow-up, respectively. Oxford Shoulder Scores (OSS) collected at six, 12, and 24 months and at three, four, and five years following randomization was plotted against time to surgery. Long-term recovery was explored by plotting six-month scores against five-year scores and agreement was illustrated with a Bland-Altman plot.