Management of severe congenital femoral deficiency: Does surgical intervention enhance prosthetic function?

BACKGROUND OBJECTIVE

The purpose of this study was to evaluate prosthetic outcome in patients with severe congenital femoral deficiency and the potential benefits of surgical intervention on prosthetic fitting and gait.

METHODS

A retrospective review identified 26 active case records with a proximal femoral focal deficiency using a prosthesis. Validated outcome measures evaluated comfort, function, and prosthetic use and quality-of-life assessment. Outcome compared age groups and surgical intervention. Gait analysis performed in 7 patients further evaluated hip and knee function.

RESULTS

Eleven male patients and 15 female patients, including 13 children (mean age 10 years, range 5-16) and 13 adults (mean age 36 years, range 23-63) were evaluated. Better prosthetic function and PedsQL scores were recorded in the pediatric group. There was a trend for better scores after surgery. Gait analysis demonstrated reduced hip extension compensated by knee flexion in 3 patients, 2 patients had hip extension with near normal kinematics, 1 untreated patient walked with an unsteady gait, and the remaining walked well using an ischial-bearing prosthesis with pelvic compensatory movements.

CONCLUSION

The management strategy in severe proximal femoral focal deficiency remains a major challenge. Hip reconstruction seems to improve functional scores. Overall, the scores seem to decline into adulthood but not significantly. Gait analysis before further surgical intervention is recommended because compensatory knee flexion may improve step length in terminal stance. Limited numbers, with short follow-up, prevents clear guidance on the benefit of surgery.

Miserable malalignment syndrome associated knee pain: a case for infra-tubercle tibial de-rotation osteotomy using an external fixator

INTRODUCTION

Miserable malalignment syndrome is a complex torsional lower limb deformity with limited consensus on surgical treatment. We present the outcome of de-rotation of the tibia alone using an external fixator.

METHODS

Fifteen patients (22 segments) were operated on between 2012 and 2020; 13 presented with anterior knee pain, and two presented with out-toeing. Gait analysis was done in nine patients, and CT scan rotational profile, including tibial tubercle-trochlear groove distance, femoral version, and tibial torsion, were calculated. Kujala knee pain score and visual analogue pain score (VAS) were recorded. All underwent infra-tubercular osteotomy of the tibia and midshaft osteotmy of the fibula and application of a hexapod circular frame to gradually internally rotate the tibia until the foot aligned with the patella.

RESULTS

There was no preoperative clinical or radiographic evidence for patellar instability, femoral anteversion 30° (21°-54°), and external tibial torsion 50° (37-70). The mean age at surgery was 21 years (12-37) with a mean follow-up of 20 months (9-83). All osteotomies healed, and the frames were removed at a mean of 111 days (80-168). The mean VAS score improved from 8(5-9) to 1(0-4) postoperatively (P < 0.001). The mean Kujala knee pain score increased from 53 (30-75) to 92 (54-100) postoperatively (P < 0.001). The mean preoperative foot progression angle (FPA) was 37° (20°-50°), with 13 postoperatively walking with neutral FPA. One patient walked with symmetrical + 10° and the other with - 5° FPA. All patients reported relief of knee pain and were satisfied with the alignment.

CONCLUSION

Gradual correction of severe external tibia torsion with a hexapod external fixator and an infra-tubercle tibial osteotomy could provide an optimum method to eliminate knee pain and improve limb alignment in miserable malalignment syndrome.

Early Weight Bearing in Lengthening Nails

How to cite this article: Tissingh EK, Wright J, Calder P. Early Weight Bearing in Lengthening Nails. Strategies Trauma Limb Reconstr 2023;18(1):63.

Difficulties associated with Reporting Radiographer working practices - A narrative evidence synthesis

OBJECTIVES

This narrative synthesis of evidence identifies and explores issues that impact upon the expansion or effectiveness of Reporting Radiographers working in all diagnostic modalities within the United Kingdom (UK). The publication focuses on working practices affecting trainees and qualified Reporting Radiographers.

KEY FINDINGS

Fourteen studies informed the themes of this article, they were published between 2014 and 2021. Delays to commencement of reporting roles and variance in performance monitoring was common. Lack of formalisation, overly restrictive and out of date scopes of practice were also found. Whilst, staffing shortages contributed to underutilisation. Failure to utilise skills was most prevalent in cross sectional imaging modalities. Considerable variance in practice was also found between centres. Meanwhile, Reporting Radiographer involvement in professional development, education and research is far from universal and often dependant on individuals sacrificing their own time.

CONCLUSION

Governance in many centres would benefit from renewal and standardisation, particularly relating to scopes of practice and performance monitoring audits. Measures are also required to encourage compliance with guidance, address staffing issues and reduce variation between centres. Failure to address these issues has the potential to impair collaboration, delay patient care and increase economic inefficiencies whilst negatively impacting satisfaction for service users and staff. Lack of involvement in professional development, education and research suggests Reporting Radiographers are not accomplishing their full potential, educating the next generation of the reporting workforce and driving evidence-based change for further development of the specialism.

IMPLICATIONS FOR PRACTICE

Better use of the existing workforce is essential to increase productivity, value, and security of Reporting Radiographer services, which are essential to improve patient outcomes and efficiency.

Difficulties associated with access to training and clinical support for Reporting Radiographers - A narrative evidence synthesis

OBJECTIVES

This narrative synthesis of evidence identifies and explores issues that impact upon the expansion or effectiveness of Reporting Radiographers working in all diagnostic modalities within the United Kingdom (UK). The publication focuses on accessibility to training for prospective Reporting Radiographers as well as clinical support within and beyond training.

KEY FINDINGS

Fifteen studies informed the themes of this article, they were published between 2014 and 2021. Reporting Radiographers often found it difficult find support during training and once qualified, this was usually due to the availability and workload of supervising staff. Although resistance and obstruction were experienced by many. Concerns relating to pay, promotion and interest were expressed by some respondents whilst access to courses and finance were highlighted as areas of variance across the UK.

CONCLUSION

Inadequate support of Reporting Radiographers is impairing expansion of the specialism, whilst impacting capability and morale. This increases risk of patient harm, delays to care and inefficiency, it also threatens the sustainability of services. Negative interactions between Reporting Radiographers and Radiologists or managers is disappointing considering development of the specialism; evidence of Reporting Radiographer effectiveness and current collaboration between Royal College of Radiologists and Society of Radiographers. Issues raised in relation to pay/promotion and litigation could be clarified with ease, this should be considered when guidance is updated. Access to finance and courses is a major barrier in some regions of the UK. Scope exists for further exploration of training. England has used grants to facilitate uptake, these may prove to be an important tool in other countries.

IMPLICATIONS FOR PRACTICE

Drivers to increase recruitment should be implemented alongside measures to facilitate accessibility to training and improvements to support infrastructure.

Use of the Pixel Value Ratio Following Intramedullary Limb Lengthening: Uncomplicated Full Weight-bearing at Lower Threshold Values

Aims

The pixel value ratio (PVR) can be used to assess regenerate consolidation after lengthening and guide advice for full weight-bearing (FWB). This study aimed to analyse the PVR in adults having femoral lengthening, the time to FWB and compare findings with the reported values in the literature.

Materials and methods

A retrospective database review identified 100 eligible patients who underwent lengthening using the PRECICE nail (68 antegrade and 32 retrograde). The PVR was calculated in each cortex on plain radiographs at every visit. The ratio between the regenerate and an average from the adjacent normal bone was calculated and plotted against the clinical decision to allow FWB.

Results

Eighty-seven patients (58 men and 29 women) were assessed; eleven had bilateral lengthening and two patients underwent lengthening twice. The median age was 30.5 years. The underlying cause of shortening was post-traumatic in 46%, with the remaining due to a wide variety of causes, including congenital 16%, syndromic 12% and other causes. The median lengthening achieved was 45 mm, at a median of 57.5 days. The PVR increased with each visit (p <0.0001). FWB was allowed at a median of 42 days after the last day of lengthening, with PVR values of 0.83, 0.84, 0.93 and 0.84 for the anterior, posterior, medial and lateral cortex noted, respectively (average 0.85). There were no implant failures, shortening or regenerate fractures. No differences were detected between antegrade and retrograde nails or with lengthening greater or less than 45 mm. One surgeon allowed earlier FWB at median 31 days with no nail failures.

Conclusion

PVR is a valuable tool that quantifies regenerate maturity and provides objectivity in deciding when to allow FWB after intramedullary lengthening with the PRECICE nail. FWB was permitted at an earlier time point, corresponding with lower PVR values than have been reported in the literature and with no mechanical failure or regenerate deformation.

How to cite this article

Elsheikh AA, Wright J, Stoddart MT, et al. Use of the Pixel Value Ratio Following Intramedullary Limb Lengthening: Uncomplicated Full Weight-bearing at Lower Threshold Values. Strategies Trauma Limb Reconstr 2022;17(1):14–18.

Osteofibrous dysplasia of the tibia : the importance of deformity in surveillance

AIMS

Osteofibrous dysplasia (OFD) is a rare benign lesion predominantly affecting the tibia in children. Its potential link to adamantinoma has influenced management. This international case series reviews the presentation of OFD and management approaches to improve our understanding of OFD.

METHODS

A retrospective review at three paediatric tertiary centres identified 101 cases of tibial OFD in 99 patients. The clinical records, radiological images, and histology were analyzed.

RESULTS

Mean age at presentation was 13.5 years (SD 12.4), and mean follow-up was 5.65 years (SD 5.51). At latest review, 62 lesions (61.4%) were in skeletally mature patients. The most common site of the tibial lesion was the anterior (76 lesions, 75.2%) cortex (63 lesions, 62.4%) of the middle third (52 lesions, 51.5%). Pain, swelling, and fracture were common presentations. Overall, 41 lesions (40.6%) presented with radiological deformity (> 10°): apex anterior in 97.6%. A total of 41 lesions (40.6%) were treated conservatively. Anterior bowing < 10° at presentation was found to be related to successful conservative management of OFD (p = 0.013, multivariable logistic regression). Intralesional excision was performed in 43 lesions (42.6%) and a wide excision of the lesion in 19 (18.8%). A high complication rate and surgical burden was found in those that underwent a wide excision regardless of technique employed. There was progression/recurrence in nine lesions (8.9%) but statistical analysis found no predictive factors. No OFD lesion transformed to adamantinoma.

CONCLUSION

This study confirms OFD to be a benign bone condition with low rates of local progression and without malignant transformation. It is important to distinguish OFD from adamantinoma by a histological diagnosis. Focus should be on angular deformity, monitored with full-length tibial radiographs. Surgery is indicated in symptomatic patients and predicted by the severity of the initial angular deformity. Surgery should focus more on the deformity rather than the lesion. Cite this article: Bone Joint J 2022;104-B(2):302-308.

Development of a patient-reported outcome measure in limb reconstruction : a pilot study assessing face validity

Aims

Patients undergoing limb reconstruction surgery often face a challenging and lengthy process to complete their treatment journey. The majority of existing outcome measures do not adequately capture the patient-reported outcomes relevant to this patient group in a single measure. Following a previous systematic review, the Stanmore Limb Reconstruction Score (SLRS) was designed with the intent to address this need for an effective instrument to measure patient-reported outcomes in limb reconstruction patients. We aim to assess the face validity of this score in a pilot study.

Methods

The SLRS was designed following structured interviews with several groups including patients who have undergone limb reconstruction surgery, limb reconstruction surgeons, specialist nurses, and physiotherapists. This has subsequently undergone further adjustment for language and clarity. The score was then trialled on ten patients who had undergone limb reconstruction surgery, with subsequent structured questioning to understand the perceived suitability of the score.

Results

Ten patients completed the score and the subsequent structured interview. Considering the tool as a whole, 100% of respondents felt the score to be comprehensible, relevant, and comprehensive regarding the areas that were important to a patient undergoing limb reconstruction surgery. For individual questions, on a five-point Likert scale, importance/relevance was reported as a mean of 4.78 (4.3 to 5.0), with ability to understand rated as 4.92 (4.7 to 5.0) suggesting high levels of relevance and comprehension. Flesch-Kincaid reading grade level was calculated as 5.2 (10 to 11 years old).

Conclusion

The current SLRS has been shown to have acceptable scores from a patient sample regarding relevance, comprehensibility, and comprehensiveness. This suggests face validity, however further testing required and is ongoing in a larger cohort of patients to determine the reliability, responsiveness, precision, and criterion validity of the score in this patient group.

Cite this article: Bone Jt Open 2021;2(9):705–709.

Analysis of retrieved STRYDE nails

Aims

The aim of this study was to present the first retrieval analysis findings of PRECICE STRYDE intermedullary nails removed from patients, providing useful information in the post-market surveillance of these recently introduced devices.

Methods

We collected ten nails removed from six patients, together with patient clinical data and plain radiograph imaging. We performed macro- and microscopic analysis of all surfaces and graded the presence of corrosion using validated semiquantitative scoring methods. We determined the elemental composition of surface debris using energy dispersive x-ray spectroscopy (EDS) and used metrology analysis to characterize the surface adjacent to the extendable junctions.

Results

All nails were removed at the end of treatment, having achieved their intended lengthening (20 mm to 65 mm) and after regenerate consolidation. All nails had evidence of corrosion localized to the screw holes and the extendable junctions; corrosion was graded as moderate at the junction of one nail and severe at the junctions of five nails. EDS analysis showed surface deposits to be chromium rich. Plain radiographs showed cortical thickening and osteolysis around the junction of six nails, corresponding to the same nails with moderate – severe junction corrosion.

Conclusion

We found, in fully united bones, evidence of cortical thickening and osteolysis that appeared to be associated with corrosion at the extendable junction; when corrosion was present, cortical thickening was adjacent to this junction. Further work, with greater numbers of retrievals, is required to fully understand this association between corrosion and bony changes, and the influencing surgeon, implant, and patient factors involved.

Cite this article: Bone Jt Open 2021;2(8):599–610.

Early results from a single centre's experience with the STRYDE nail : a cause for concern?

AIMS

The STRYDE nail is an evolution of the PRECICE Intramedullary Limb Lengthening System, with unique features regarding its composition. It is designed for load bearing throughout treatment in order to improve patient experience and outcomes and allow for simultaneous bilateral lower limb lengthening. The literature published to date is limited regarding outcomes and potential problems. We report on our early experience and raise awareness for the potential of adverse effects from this device.

METHODS

This is a retrospective review of prospective data collected on all patients treated in our institution using this implant. We report the demographics, nail accuracy, reliability, consolidation index, and cases where concerning clinical and radiological findings were encountered. There were 14 STRYDE nails implanted in nine patients (three male and six female) between June 2019 and September 2020. Mean age at surgery was 33 years (14 to 65). Five patients underwent bilateral lengthening (two femoral and three tibial) and four patients unilateral femoral lengthening for multiple aetiologies.

RESULTS

At the time of reporting, eight patients (13 implants) had completed lengthening. Osteolysis and periosteal reaction at the junction of the telescopic nail was evident in nine implants. Five patients experienced localized pain and swelling. Macroscopic appearances following retrieval were consistent with corrosion at the telescopic junction. Tissue histology was consistent with effects of focal metallic wear debris.

CONCLUSION

From our early experience with this implant we have found the process of lengthening to be accurate and reliable with good regenerate formation and consolidation. Proposed advantages of early load bearing and the ability for bilateral lengthening are promising. We have, however, encountered concerning clinical and radiological findings in several patients. We have elected to discontinue its use to allow further investigation into the retrieved implants and patient outcomes from users internationally. Cite this article: Bone Joint J 2021;103-B(6):1168-1172.

Providing a paediatric trauma and orthopaedics service during the peak of the COVID-19 pandemic: The Royal National Orthopaedic Hospital experience

INTRODUCTION

In response to the COVID-19 pandemic, there was a rapidly implemented restructuring of UK healthcare services. The The Royal National Orthopaedic Hospital, Stanmore, became a central hub for the provision of trauma services for North Central/East London (NCEL) while providing a musculoskeletal tumour service for the south of England, the Midlands, and Wales and an urgent spinal service for London. This study reviews our paediatric practice over this period in order to share our experience and lessons learned. Our hospital admission pathways are described and the safety of surgical and interventional radiological procedures performed under general anaesthesia (GA) with regards to COVID-19 in a paediatric population are evaluated.

METHODS

All paediatric patients (≤ 16 years) treated in our institution during the six-week peak period of the pandemic were included. Prospective data for all paediatric trauma and urgent elective admissions and retrospective data for all sarcoma admissions were collected. Telephone interviews were conducted with all patients and families to assess COVID-19 related morbidity at 14 days post-discharge.

RESULTS

Overall, 100 children underwent surgery or interventional radiological procedures under GA between 20 March and 8 May 2020. There were 35 trauma cases, 20 urgent elective orthopaedic cases, two spinal emergency cases, 25 admissions for interventional radiology procedures, and 18 tumour cases. 78% of trauma cases were performed within 24 hours of referral. In the 97% who responded at two weeks following discharge, there were no cases of symptomatic COVID-19 in any patient or member of their households.

CONCLUSION

Despite the extensive restructuring of services and the widespread concerns over the surgical and anaesthetic management of paediatric patients during this period, we treated 100 asymptomatic patients across different orthopaedic subspecialties without apparent COVID-19 or unexpected respiratory complications in the early postoperative period. The data provides assurance for health care professionals and families and informs the consenting process.Cite this article: Bone Joint Open 2020;1-6:287-292.

Providing a paediatric trauma and orthopaedics service during the peak of the COVID-19 pandemic

Introduction

In response to the COVID-19 pandemic, there was a rapidly implemented restructuring of UK healthcare services. The The Royal National Orthopaedic Hospital, Stanmore, became a central hub for the provision of trauma services for North Central/East London (NCEL) while providing a musculoskeletal tumour service for the south of England, the Midlands, and Wales and an urgent spinal service for London. This study reviews our paediatric practice over this period in order to share our experience and lessons learned. Our hospital admission pathways are described and the safety of surgical and interventional radiological procedures performed under general anaesthesia (GA) with regards to COVID-19 in a paediatric population are evaluated.

Methods

All paediatric patients (≤ 16 years) treated in our institution during the six-week peak period of the pandemic were included. Prospective data for all paediatric trauma and urgent elective admissions and retrospective data for all sarcoma admissions were collected. Telephone interviews were conducted with all patients and families to assess COVID-19 related morbidity at 14 days post-discharge.

Results

Overall, 100 children underwent surgery or interventional radiological procedures under GA between 20 March and 8 May 2020. There were 35 trauma cases, 20 urgent elective orthopaedic cases, two spinal emergency cases, 25 admissions for interventional radiology procedures, and 18 tumour cases. 78% of trauma cases were performed within 24 hours of referral. In the 97% who responded at two weeks following discharge, there were no cases of symptomatic COVID-19 in any patient or member of their households.

Conclusion

Despite the extensive restructuring of services and the widespread concerns over the surgical and anaesthetic management of paediatric patients during this period, we treated 100 asymptomatic patients across different orthopaedic subspecialties without apparent COVID-19 or unexpected respiratory complications in the early postoperative period. The data provides assurance for health care professionals and families and informs the consenting process. Cite this article: Bone Joint Open 2020;1-6:287–292.

Regenerate Deformity with the Precice Tibial Nail

Limb lengthening by distraction osteogenesis is an accepted orthopaedic surgical technique. The Precice intramedullary lengthening system is the most recent innovation in limb lengthening. Early results have been favourable in femoral lengthening but there is little reported on the outcome in tibial lengthening. The aim of this study is to present our early results of Precice tibial lengthening, and the stepwise evolution of our surgical technique.

Materials and methods

A case series of 17 consecutive tibial lengthenings were prospectively analysed. Healing index, length achieved, range of motion, and complications were recorded. The initial cases followed the recommended surgical technique. Progressive regenerate deformity during lengthening required changes to the surgical method.

Results

No cases were lost to follow-up. All the nails lengthened at the desired rate. There were no complications of infection or poor regenerate formation. Progressive valgus and procurvatum was prevented in later cases by the positioning of Poller blocking screws at the time of nail insertion.

Conclusion

The tibial Precice nail is successful in obtaining length and good regenerate formation. The recommended technique was insufficient to control the deforming forces from the lower limb muscle compartments during lengthening. We therefore recommend the addition of multiple blocking screws in an amended technique.

How to cite this article

Wright SE, Goodier WD, Calder P. Regenerate Deformity with the Precice Tibial Nail. Strategies Trauma Limb Reconstr 2020;15(2):98-105.

Reducing the Risk of Ring Breakage in Taylor Spatial Frames: The Effect of Frame Configuration on Strain at the Half-ring Junction

Aim

We have encountered four cases with Taylor spatial frames (TSF) (Smith & Nephew, Memphis, TN, USA) with breakage at the half-ring junction of the distal ring. This study examines the strain produced on different locations of the distal ring during loading and the effects on the strain of altering the frame construct.

Materials and methods

We mounted two ring TSF constructs on tibia saw bone models. The proximal ring was the same in all constructs and consisted of a 2/3 180 mm ring attached with three wires. Construct 1 is reproducing the configuration of cases where failure was seen. The distal 155 mm ring is attached with three half pins. The half-ring junction is located in the midline. Construct 2 has a different half pin placement and an additional wire on the distal ring. Constructs 3 and 4 have the same half pin configuration to construct 1 but the distal ring is rotated 60° internally and externally, respectively. Strain gauges were attached to different locations and measurements recorded during loading. Statistical analysis was performed.

Results

Highest strain values were recorded at the half-ring junction of constructs 1 and 2 (>600 microstrains (με) in tension). Rotating the ring 60° internally significantly reduces the strain at the half-ring junction (<300 με) whilst external rotation by 60° further reduces the strain (<180 με). Ring strain is higher in areas close to half pin attachments.

Conclusion

The highest strain is in the half-ring junction as the half rings are subjected to different loading modes. The thickness of the half-ring is halved and the second moment of area reduced further increasing breakage risk. Placing this junction close to the half pin–frame interface, as dictated by the anatomical safe zone further increases the strain. Rotating the distal ring 60° significantly reduces the strain at the half-ring junction.

Clinical significance

Ring breakage is a rare but significant complication. This is the first study to address this potential mode of TSF failure. Insights and technical tips from this study can help reduce this.

How to cite this article

Iliadis AD, Bebja R, Wang K, et al. Reducing the Risk of Ring Breakage in Taylor Spatial Frames: The Effect of Frame Configuration on Strain at the Half-ring Junction. Strategies Trauma Limb Reconstr 2020;15(3):146–150.

Thromboprophylaxis in Intramedullary Limb Lengthening Surgery

Aim

The use of intramedullary lengthening devices is becoming increasingly popular. There are limited data regarding the incidence of venous thromboembolism following intramedullary lengthening surgery and no reports or guidance for current practice on use of thromboprophylaxis. Following a case of post-operative deep vein thrombosis in our institution, we felt that it is important to assess best practice. We conducted a national survey to collect data that would describe current practice and help develop consensus for treatment.

Materials and methods

We identified surgeons across the UK that perform adult intramedullary limb lengthening through the British Limb Reconstruction Society membership and a Precise Users database. Surgeons were contacted and asked to respond to an online survey. Responses to thromboprophylaxis regimes employed in their practice and cases of venous thromboembolism were collated.

Results

24 out of 54 surgeons identified responded with a total of 454 cases of adult intramedullary lengthening (352 femoral and 102 tibial nails) performed over a five year period (January 2015–January 2020). Only one case of deep venous thrombosis (DVT) following femoral lengthening was reported. There is wide variability in practice both in terms of thromboprophylaxis risk assessment, choice of medications and duration of treatment. The vast majority of surgeons (85%) felt that there was insufficient evidence available to guide their practice.

Conclusions

Intramedullary lengthening is a surgical treatment growing in popularity. There are limited data available to guide decision-making regarding aspects of treatment such as thromboprophylaxis. This is reflected in the wide variation in practice reported in this study. There are both a need and a desire to gather data that will allow us to come to a consensus and to guide safe practice.

Clinical significance

Venous thromboembolism is a potential complication of lower limb lengthening surgery. We report on national incidence and current practices of thromboprophylaxis to allow for informed decision-making and help develop consensus for best practice.

How to cite this article

Iliadis AD, Timms A, Fugazzotto S, et al. Thromboprophylaxis in Intramedullary Limb Lengthening Surgery. Strategies Trauma Limb Reconstr 2020;15(3):151-156.

An experimental evaluation of fracture movement in two alternative tibial fracture fixation models using a vibrating platform

Several studies have investigated the effect of low-magnitude-high-frequency vibration on the outcome of fracture healing in animal models. The aim of this study was to quantify and compare the micromovement at the fracture gap in a tibial fracture fixed with an external fixator in both a surrogate model of a tibial fracture and a cadaver human leg under static loading, both subjected to vibration. The constructs were loaded under static axial loads of 50, 100, 150 and 200 N and then subjected to vibration at each load using a commercial vibration platform, using a DVRT sensor to quantify static and dynamic fracture movement. The overall stiffness of the cadaver leg was significantly higher than the surrogate model under static loading. This resulted in a significantly higher fracture movement in the surrogate model. Under vibration, the fracture movements induced at the fracture gap in the surrogate model and the cadaver leg were 0.024 ± 0.009 mm and 0.016 ± 0.002 mm, respectively, at 200 N loading. Soft tissues can alter the overall stiffness and fracture movement recorded in biomechanical studies investigating the effect of various devices or therapies. While the relative comparison between the devices or therapies may remain valid, absolute magnitude of recordings measured externally must be interpreted with caution.

‘Rail and Nail’ bifocal management of atrophic femoral nonunion

Aims

The management of a significant bony defect following excision of a diaphyseal atrophic femoral nonunion remains a challenge. We present the outcomes using a combined technique of acute femoral shortening, stabilized with a long retrograde intramedullary nail, accompanied by bifocal osteotomy compression and distraction osteogenesis with a temporary monolateral fixator.

Patients and Methods

Eight men and two women underwent the ‘rail and nail’ technique between 2008 and 2016. Proximal locking of the nail and removal of the external fixator was undertaken once the length of the femur had been restored and prior to full consolidation of the regenerate.

Results

The mean lengthening was 7 cm (3 to 11). The external fixator was removed at a mean of 127 days (57 to 220). The mean bone healing index was 28 days/cm and the mean external fixation index was 20 days/cm (11 to 18). There were no superficial or deep infections.

Conclusion

This small retrospective study shows encouraging results for a combined technique, enabling compression of the femoral osteotomy, alignment, and controlled lengthening. Removal of the fixator and proximal locking of the nail reduces the risk of complications and stabilizes the femur with the maximum working length of the nail. Cite this article: Bone Joint J 2018;100-B:634–9.

Posteromedial bowing of the tibia: a benign condition or a case for limb reconstruction?

PURPOSE

To review the initial deformity and subsequent remodelling in posteromedial bowing of the tibia and the outcome of limb reconstruction in this condition.

PATIENTS AND METHODS

In all, 38 patients with posteromedial bowing of the tibia presenting between 2000 and 2016 were identified. Mean follow-up from presentation was 78 months. A total of 17 patients underwent lengthening and deformity correction surgery, whilst three further patients are awaiting lengthening and deformity correction procedures.

RESULTS

The greatest correction of deformity occurred in the first year of life, but after the age of four years, remodelling was limited. The absolute leg-length discrepancy (LLD) increased throughout growth with a mean 14.3% discrepancy in tibial length. In the lengthening group, mean length gained per episode was 45 mm (35 to 60). Mean duration in frame was 192 days, with a mean healing index of 42.4 days/cm. Significantly higher rates of recurrence in LLD were seen in those undergoing lengthening under the age of ten years (p = 0.046). Four contralateral epiphysiodeses were also performed.

CONCLUSION

Posteromedial bowing of the tibia improves spontaneously during the first years of life, but in 20/38 (53%) patients, limb reconstruction was indicated for significant residual deformity and/or worsening LLD. For larger discrepancies and persistent deformity, limb reconstruction with a hexapod external fixator should be considered as part of the treatment options.

LEVEL OF EVIDENCE

Level IV (Case series).

A comparison of functional outcome between amputation and extension prosthesis in the treatment of congenital absence of the fibula with severe limb deformity

PURPOSE

Complete fibula absence often presents with significant lower-limb deformity. Parental counselling regarding management is paramount in achieving the optimum functional outcome. Amputation offers a single surgical event with minimal complications. This study compares outcomes with an amputation protocol to those using an extension prosthesis.

METHOD

Thirty-two patients were identified. Nine patients (2 males, 7 females; median age at assessment of 23.5 years) used an extension prosthesis. Twenty-three patients (16  males, 7 females; median age at assessment of eight years) underwent 25 amputations during childhood. Mobility was assessed using SIGAM and K scores. Quality of life was assessed using the PedsQL inventory questionnaire; pain by a verbal severity score.

RESULTS

The 19 Syme and one Boyd amputation in 19 patients were performed early (mean age 15 months). Four Syme and one trans-tibial amputation in four patients took place in older children (mean age 6.6 years). Only two underwent tibial kyphus correction to aid prosthetic fitting. K scores were significantly higher (mean 4 vs 2) and pain scores lower in the amputation group allowing high impact activity compared with community ambulation with an extension prosthesis. The SIGAM and PedsQL scores were all better in the amputation group, but not significantly so.

CONCLUSION

Childhood amputation for severe limb length inequality and foot deformity in congenital fibula absence offers excellent short-term functional outcome with prosthetic support. The tibial kyphus does not need routine correction and facilitates prosthetic suspension. Accommodative extension prostheses offer reasonable long-term function but outcome scores are lower.

A protocol for the use of closed reduction in children with developmental dysplasia of the hip incorporating open psoas and adductor releases and a short-leg cast: Mid-term outcomes in 113 hips

AIMS

Our aim was to assess the effectiveness of a protocol involving a standardised closed reduction for the treatment of children with developmental dysplasia of the hip (DDH) in maintaining reduction and to report the mid-term results.

METHODS

A total of 133 hips in 120 children aged less than two years who underwent closed reduction, with a minimum follow-up of five years or until subsequent surgery, were included in the study. The protocol defines the criteria for an acceptable reduction and the indications for a concomitant soft-tissue release. All children were immobilised in a short- leg cast for three months. Arthrograms were undertaken at the time of closed reduction and six weeks later. Follow-up radiographs were taken at six months and one, two and five years later and at the latest follow-up. The Tönnis grade, acetabular index, Severin grade and signs of osteonecrosis were recorded.

RESULTS

A total of 67 hips (51%) were Tönnis grade 3/4 hips. By 12 months, 20 reductions (15%) had not been maintained, and these required open reduction. In all, 55% of these were Severin 1; the others were Severin 2, due to minor acetabular dysplasia. Of the 113 successful closed reductions, 98 hips (87%) were Severin 1. Surgery for residual DDH was offered for ten hips. Osteonecrosis was seen in 32 hips (29%) but was transient in 28. In total, two children (1.5%) had severe osteonecrosis. Bilateral dislocations were significantly more likely to fail and most Tönnis 4 hips failed.

CONCLUSION

Closed reduction, with concomitant adductor and psoas release when required and the use of a short leg plaster of Paris cast for three months, can produce good mid-term results in children with DDH aged less than two years. This protocol is not recommended for Tönnis 4 hips. Cite this article: Bone Joint J 2016;98-B:1548-53.

Outcomes following femoral lengthening

Aims

Patients undergoing femoral lengthening by external fixation tolerate treatment less well when compared to tibial lengthening. Lengthening of the femur with an intramedullary device may have advantages.

Patients and Methods

We reviewed all cases of simple femoral lengthening performed at our unit from 2009 to 2014. Cases of nonunions, concurrent deformities, congenital limb deficiencies and lengthening with an unstable hip were excluded, leaving 33 cases (in 22 patients; 11 patients had bilateral procedures) for review. Healing index, implant tolerance and complications were compared.

Results

In 20 cases (15 patients) the Precice lengthening nail was used and in 13 cases (seven patients) the LRS external fixator system. The desired length was achieved in all cases in the Precice group and in 12 of 13 cases in the LRS group. The mean healing index was 31.3 days/cm in the Precice and 47.1 days/cm in the LRS group (p < 0.001). This was associated with an earlier ability to bear full weight without aids in the Precice group. There were more complications with LRS lengthening, including pin site infections and regenerate deformity. Implant tolerance and the patients’ perception of the cosmetic result were better with the Precice treatment.

Conclusion

Femoral lengthening with the Precice femoral nail achieved excellent functional results with fewer complications and greater patient satisfaction when compared with the LRS system in our patients. Cite this article: Bone Joint J 2016;98-B:1382–8.

Patterns of healing: a comparison of two proximal tibial osteotomy techniques

Several low-energy osteotomy techniques are described in the literature, but there is limited evidence comparing them. Our study evaluates the patterns of regenerate formation using two different osteotomy techniques. Two cohorts of patients underwent osteotomy of the tibia using a Gigli saw (n = 15) or De Bastiani corticotomy (n = 12) technique. The patient radiographs were assessed by the two senior authors who were blinded to the osteotomy type. Regenerate quality was assessed along the anterior, posterior, medial and lateral cortices, graded 1–5 from absent to full consolidation over time. The time to 3 cortices healed/regenerate length was calculated. The time to consolidation of the anterior, posterior, medial and lateral cortices was compared. The mean 3 cortices index in the Gigli group was 2.0 months/cm and in the De Bastiani group 1.8 months/cm. This was not a significant difference. In both groups, anterior bone formation was slower, and anterior cortical deficiency with a scalloped appearance was seen in 25 % of cases overall with no statistically significant difference between the two groups. Both Gigli saw and De Bastiani corticotomy techniques result in good bone formation following distraction osteogenesis. The anterior tibial cortex consolidates more slowly than the other cortices in both groups. This is likely due to deficient soft tissue cover and direct periosteal damage at time of osteotomy.

Understanding gut-immune interactions in management of acute infectious diarrhoea

This article discusses the role that immunity plays in the risk of diarrhoea and the potential role for probiotics in the management of acute infectious diarrhoea in older people, including antibiotic-associated diarrhoea and Clostridium difficile-associated diarrhoea.

A mosaic activating mutation in AKT1 associated with the Proteus syndrome

BACKGROUND

The Proteus syndrome is characterized by the overgrowth of skin, connective tissue, brain, and other tissues. It has been hypothesized that the syndrome is caused by somatic mosaicism for a mutation that is lethal in the nonmosaic state.

METHODS

We performed exome sequencing of DNA from biopsy samples obtained from patients with the Proteus syndrome and compared the resultant DNA sequences with those of unaffected tissues obtained from the same patients. We confirmed and extended an observed association, using a custom restriction-enzyme assay to analyze the DNA in 158 samples from 29 patients with the Proteus syndrome. We then assayed activation of the AKT protein in affected tissues, using phosphorylation-specific antibodies on Western blots.

RESULTS

Of 29 patients with the Proteus syndrome, 26 had a somatic activating mutation (c.49G→A, p.Glu17Lys) in the oncogene AKT1, encoding the AKT1 kinase, an enzyme known to mediate processes such as cell proliferation and apoptosis. Tissues and cell lines from patients with the Proteus syndrome harbored admixtures of mutant alleles that ranged from 1% to approximately 50%. Mutant cell lines showed greater AKT phosphorylation than did control cell lines. A pair of single-cell clones that were established from the same starting culture and differed with respect to their mutation status had different levels of AKT phosphorylation.

CONCLUSIONS

The Proteus syndrome is caused by a somatic activating mutation in AKT1, proving the hypothesis of somatic mosaicism and implicating activation of the PI3K-AKT pathway in the characteristic clinical findings of overgrowth and tumor susceptibility in this disorder. (Funded by the Intramural Research Program of the National Human Genome Research Institute.).

The use of tranexamic acid to reduce blood loss during total hip arthroplasty: an observational study

INTRODUCTION

To test the hypothesis that the fall in haemoglobin following total hip arthroplasty is reduced by tranexamic acid administration.

PATIENTS AND METHODS

A cohort of 64 patients were studied, 32 received tranexamic acid 20 mg/kg on induction. Surgery was performed by the senior author in a standardised fashion. Haemoglobin levels were measured 2 weeks pre- and 3 days postoperatively. Any complications were noted. The study group was matched using the bone and joint research database for age, sex, procedure, disease and pre-operative haemoglobin level.

RESULTS

In the group receiving no tranexamic acid, the mean fall in haemoglobin was 3.8 g/dl (CI of mean 3.4-4.3) and in the group treated with tranexamic acid 2.8 g/dl (CI of mean 2.5-3.2) P < 0.05. Complications included one non-fatal pulmonary embolus in the tranexamic acid group.

CONCLUSIONS

The administration of 20 mg/kg of tranexamic acid on induction of surgery is an effective method of reducing the haemoglobin fall following hip arthroplasty.

Private Costs of Patients Hospitalized with Community-Acquired Pneumonia

BACKGROUND: Community-acquired pneumonia (CAP) is a condition which frequently requires hospitalization and consequently, can result in high costs. Little is known of the additional personal resources that are used by patients hospitalized for CAP.

OBJECTIVE: To measure the private costs for persons who were hospitalized with CAP for the 30 days after being admitted to hospital using a systematic method of measurement.

METHODS: Potential personal cost items were identified by nurses familiar with the treatment of CAP and categorized. Using telephone interviews in conjunction with the cost-identification framework, 60 patients from the Edmonton, Alberta area were surveyed for their private costs associated with CAP for 30 days after admission to hospital.

RESULTS: Of the 60 patients surveyed, 49 were older than 65 years of age. The mean private cost was $505, which amounted to 5.6% of the total societal costs of $8,970. The distribution was skewed with a small number of patients that had high costs.

CONCLUSIONS: This method allows the determination of the societal costs for patients hospitalized with pneumonia, and the costs were not much greater than those to the health care system.

The use of tranexamic acid to reduce blood loss during total knee arthroplasty

HYPOTHESIS

The fall in haemoglobin following unilateral total knee arthroplasty is reduced by tranexamic acid administration.

METHODS

60 patients were studied in total, 30 received tranexamic acid 10 mg/kg on induction and a further dose shortly before the release of the tourniquet. Surgery was performed by the senior author in a standardised fashion using the Freeman Samuelson cemented total knee replacement. Haemoglobin levels were measured 2 weeks pre and 3 days post operatively. Any complications were noted. A control group was matched using the Bone and Joint Research Unit database for age, sex, disease and pre-operative haemoglobin level. This group had been monitored in the same way as the group treated with tranexamic acid.

RESULTS

In the group receiving no tranexamic acid the mean fall in haemoglobin was 2.8 g/dl (95% CI of mean 2.5-3.2) and in the group treated with tranexamic acid 1.7 g/dl (95% CI of mean 1.3-2) P<0.01. There were no complications in either group.

CONCLUSIONS

The administration of tranexamic acid is an effective method of reducing the haemoglobin fall following knee arthroplasty.

Concept mapping the needs of foster parents

This study describes the needs of foster parents as perceived by the foster parents themselves. Forty-nine parents from 30 foster families were asked to describe their needs in response to the question: "What do you need to be a good foster parent?" Five themes were apparent in their answers: (1) good working relationships; (2) cultural sensitivity; (3) harmonious and stable family relationships; (4) adequate payment for services; and (5) a range of personality characteristics and parenting skills. These themes are consistent with the literature, with the notable exception of respite, a need identified in the literature but not by the sampled foster parents. The study results lend credibility to the existing literature on the needs of foster parents.

Cost effectiveness of Streetworks' needle exchange program of Edmonton

OBJECTIVE

To conduct a cost-effectiveness analysis of the Edmonton Streetworks needle exchange program, in terms of the additional cost per HIV infection averted. The main outcome measures were needle use with and without Streetworks, HIV cases averted, and program costs.

METHODS

We conducted interviews and HIV saliva tests on a sample of street-involved intravenous drug users (IDU) who are regular Streetworks' clients. Outcomes were used in a cost-effectiveness model.

RESULTS

It is projected that the program has a cost-effectiveness of $9,500 (Canadian) per HIV infection delayed for one year.

CONCLUSIONS

The discounted cost per case averted is less than the cost of a case of AIDS. Continuing the program is a dominant strategy.

Impact of managed waiting for coronary artery bypass graft surgery on patients' perceived quality of life

BACKGROUND

Current demand for CABG surgery remains high, often exceeds available resources, and has led to the development of managed waiting lists. This study was designed to determine how being placed on a managed waiting list for > 6 weeks for CABG surgery affected patients' perceived quality of life in a Canadian center.

METHODS AND RESULTS

Telephone interviews were carried out in the setting of a large urban hospital in northern Alberta. All participants were identified from 3 waiting lists of adult patients waiting for open heart surgery. A master list of patient statements was compiled to formulate the 47-item Waiting List Impact Questionnaire (WLIQ). A total of 102 patients completed the WLIQ by telephone interview. Patients (87.5%) indicated that their quality of life had deteriorated since being placed on the waiting list. None of the patients perceived an improvement in their quality of life. Frequency data for the WLIQ provided a broad, multidimensional perspective of the experience of waiting for CABG surgery and its impact on perceived quality of life. Negative impact was found in each of 5 main themes: employment and income, physical stress, social support, frustration, and quality of life.

CONCLUSIONS

This study indicates that patients perceived a negative impact on their quality of life after being placed on a managed waiting list for CABG surgery. In the allocation of healthcare resources, attention should be paid to the impact of waiting on patients' physical well-being as well as on quality of life.

Regulation of rat liver apolipoprotein A-I, apolipoprotein A-II and acyl-coenzyme A oxidase gene expression by fibrates and dietary fatty acids

The regulation by fibrates and dietary fatty acids of the hepatic gene expression of apolipoproteins (apo) A-I and A-II, the major protein constituents of high-density lipoproteins, as well as of acyl-CoA oxidase, the rate-limiting enzyme of the peroxisomal beta-oxidation pathway, was studied in vivo in the rat and in vitro in primary cultures of rat hepatocytes. In primary hepatocytes, different fibrates decreased apo A-I and increased acyl-CoA oxidase mRNA levels, whereas apo A-II mRNA only decreased in level after treatment with fenofibric acid, but not after bezafibrate, gemfibrozil or Wy-14643 treatment. Treatment with fenofibric acid counteracted the increase in apo A-I mRNA levels observed after dexamethasone or all-trans retinoic acid treatment, whereas simultaneous addition of fenofibric acid together with all-trans retinoic acid or dexamethasone resulted in a superinduction of acyl-CoA oxidase mRNA. Addition of the n-3 polyunsaturated fatty acids (PUFAs), docosanohexaenoic acid and eicosanopentaenoic acid, or the fatty acid derivative alpha-bromopalmitate, decreased apo A-I and increased acyl-CoA oxidase mRNA in a dose-dependent and time-dependent manner, whereas apo A-II mRNA did not change significantly. Nuclear run-on experiments demonstrated that fenofibric acid and alpha-bromopalmitate decreased apo A-I and increased acyl-CoA oxidase gene expression at the transcriptional level. When rats were fed isocaloric diets enriched in saturated fat (hydrogenated coconut oil), n-6 PUFAs (safflower oil) or n-3 PUFAs (fish oil), a significant decrease in liver apo A-I and apo A-II mRNA levels was only observed after fish oil feeding. Compared to feeding low fat, liver acyl-CoA oxidase mRNA increased after fat feeding, but this effect was most pronounced (twofold) in rats fed fish oil. Results from these studies indicate that fish oil feeding reduces rat liver apo A-I and apo A-II gene expression, similar to results obtained after feeding fenofibrate. Fibrates and n-3 fatty acids (and the fatty acid derivative, alpha-bromopalmitate) down-regulate apo A-I and induce acyl-CoA oxidase gene expression through a direct transcriptional action on the hepatocyte. In contrast, only fenofibric acid, but not the other fibrates or fatty acids tested, decrease apo A-II gene expression in vitro.

Effects of dietary lipid manipulation upon inflammatory mediator production by murine macrophages

This study investigated the effects of feeding mice lipids with different fatty acid compositions upon the ability of stimulated macrophages to produce inflammatory mediators. Weanling mice were fed for 8 weeks on a low-fat (LF; 2.5% by weight) diet or on diets containing 20% by weight of hydrogenated coconut oil (HCO), olive oil (OO), safflower oil (SO), or menhaden (fish) oil (MO). Thioglycollate-elicited peritoneal macrophages were isolated. Macrophages isolated from MO-fed mice produced less PGE2, 6-keto-PGF1 alpha, TXB2, and interleukin-6 in response to lipopolysaccharide (LPS) stimulation than those from mice fed each of the other diets. Macrophages from mice fed the OO, SO, or MO diets produced less tumor necrosis factor alpha in response to LPS stimulation than those from mice fed the LF or HCO diets. There was no effect of dietary lipid manipulation upon the production of interleukin-1 by LPS-stimulated macrophages. Macrophages from mice fed the MO diet produced more superoxide and hydrogen peroxide in response to phorbol ester stimulation than those from mice fed each of the other diets. In response to unopsonized zymosan, macrophages from mice fed the SO or MO diets produced more hydrogen peroxide than macrophages from mice fed the other diets. LPS-stimulated nitric oxide production was greater from macrophages from OO-, SO-, or MO-fed mice than from those fed the LF or HCO diets. Thus, the nature of the lipid consumed in the diet has significant effects upon the production of a variety of inflammatory mediators by macrophages. The most potent effect is caused by fish oil consumption. Possible mechanisms by which dietary fatty acids, particularly the n-3 polyunsaturated fatty acids found in fish oils, could affect mediator production by macrophages are described. The clinical relevance of such effects is discussed.

Studies on the effects of growth hormone administration in vivo on the rates of glucose transport and utilization in rat skeletal muscle

The effects of growth hormone (GH) administration to rats in vivo on the sensitivity of the rate of glucose utilization to insulin were studied in soleus muscles isolated from these rats. A single injection of GH did not increase the rate of glucose transport within 1-2 h. However, 12 h after, the rate of glucose transport was increased at 10 mU insulin l-1 and was accompanied by a similar increase in the rate of lactate formation but no change in the rate of glycogen synthesis. Prolonged treatment with GH decreased the rate of glucose transport and glycogen synthesis and increased the content of glucose 6-phosphate at physiological levels of insulin but did not affect the rate of lactate formation. These results suggest that: (a) GH does not increase the rate of glucose transport acutely; however, after several hours, the sensitivity of glucose transport and glycolysis to insulin are increased; (b) prolonged elevations of the level of GH in plasma decrease the sensitivity of the rate of glucose transport and glycogen synthesis to insulin. However, redirection of glucose residues away from the pathway of glycogen synthesis towards that of glycolysis and a possible increase in the rate of glycogenolysis maintain a normal rate of lactate formation, although the rate of glucose transport is decreased.

Factors related to attribution of blame in father-daughter incest

Attribution of blame in father-daughter incest using the Jackson Incest Blame Scale and the Attitudes Towards Incest Scale--Revised was investigated through a questionnaire mailed to a random sample of the general adult population. 300 respondents completed the questionnaires (207 women, 93 men). Based on factor analyses, five blame subscales were identified for the Jackson Incest Blame Scale, i.e., Victim, Situational, Societal, Offender, and Offender Mental Status, the last being unique to this study. Ratings by men attributed more blame on the Victim and Situational subscales than did those by women. Scores for 51 victims of childhood sexual abuse on the Jackson Incest Blame Scale did not differ from those of 249 nonvictims. Scores on subscales of the Attitudes Towards Incest Scale--Revised (Credibility, Power, Parental Role, Victimization) were moderately correlated with ratings on Jackson's scale. More total blame and more blame of victim were associated with lower rated credibility towards a claim of incest; lower rated blame of victim was related to greater recognition of the incestuous father's coercive role.

The regulatory, informational, and immunomodulatory roles of fat fuels

Fat oxidation provides a fuel for many tissues and it provides an important signal to decrease glucose utilization and oxidation in muscle and so conserve glucose for essential organs such as the brain. The control of fatty acid oxidation is achieved in part through its plasma concentrations, which may be precisely controlled by the triacylglycerol-fatty acid substrate cycle, which can also, if oxidation is taken into account, be viewed as a branch point in this important pathway. Branch points may provide precision in regulation if one of the fluxes at the branch is low compared with the other flux. Both branch points and substrate cycles are energetically expensive and may account for some of the increases in energy expenditure in conditions of injury, burns, and sepsis and in the postexercise condition. Fatty acids, through effects on plasma free tryptophan concentrations and hence 5-hydroxytryptamine concentrations in the brain, may play a role in central fatigue. Polyunsaturated fatty acids are claimed to have immunosuppressive properties. Work has been done to provide a biochemical analysis of how they might influence some functions of cells of the immune system.

Effects of in-vivo administration of insulin-like growth factor-I on the rate of glucose utilization in the soleus muscle of the rat

This study investigated the effects of insulin-like growth factor-I (IGF-I) administered to rats in vivo on the soleus muscle isolated from these rats. In order to study the interactions between IGF-I and insulin, the soleus muscles were incubated in the presence of various concentrations of insulin. IGF-I (190-200 micrograms) was given twice daily; the rats were killed 1 h after one injection of IGF-I (acute administration) or after treatment with IGF-I for 10 days (prolonged administration). The level of IGF-I in plasma was increased by approximately 100% after acute administration and by around 30% after 10 days of treatment with IGF-I. Acute administration of IGF-I to the rats increased the flux of glucose to hexose monophosphate and the rates of lactate formation and glycogen synthesis in the soleus muscles; however, the responsiveness of these muscles to insulin was lost: the increase in the rate of glucose utilization by IGF-I at physiological concentrations of insulin (10 or 100 mU/l) was similar to that observed at maximal concentrations of insulin (1000 mU/l). Similar results were obtained after prolonged treatment of the rats with IGF-I; however, the increase in the rate of glucose utilization was less pronounced than when IGF-I was given acutely and the muscles were still capable of responding to insulin.(ABSTRACT TRUNCATED AT 250 WORDS)