The St Leger total knee replacement is a bicondylar prosthesis developed as a cheaper alternative to other similar implants of its time. Between October 1993 and June 1999, 144 St Leger total knee replacements were implanted in 114 patients. The aim of this study was to clinically and radiologically assess these patients after a mean follow up of 10.22 years. Between February and July 2007 ninety-one patients recalled for clinical evaluation (using functional and objective Knee Society Scores) and radiological assessment (using the Knee Society Scoring System). 11 patients had died and 12 were lost to follow up or were medically unfit to attend evaluation. Of the ninety-one patients recalled, 18 had had their prostheses revised (19 knees). 63% of prostheses had survived 10 years or more. Of the patients with St Leger knees in situ (99 knees) the American Knee Scores showed 78% poor, 10% fair, 6% good and 6% excellent results. Radiological assessment identified 12 arthroplasties that had failed (5 femoral components, 5 tibial components and 4 patellae,) 58 that needed close follow up (18 femoral components, 31 tibial components and 38 patellae) and 29 that were well fixed. A best-case Kaplan-Meier cumulative survivorship was 87% at 10 years. (Worst-case was 71% at 10 years). These 10 year results showed that the St Leger total knee prosthesis did not perform as well as other bicondylar prostheses of the same generation and had a higher revision rate. Despite favourable published mid-term results, the long-term results for the St Leger total knee replacement have shown it to be unreliable and not worth the initial financial saving

The St Leger total knee replacement is a bicondylar prosthesis developed as an cheaper alternative to other similar implants of its time. Between October 1993 and June 1999, 144 St Leger total knee replacements were implanted in 114 patients. The aim of this study was to clinically and radiologically assess these patients after a mean follow up of 10.22 years. Between February and July 2007 ninety-one patients recalled for clinical evaluation (using functional and objective American Knee Society Scores) and radiological assessment (using the American Knee Society Scoring System). 11 patients had died and 12 were lost to follow up or were medically unfit to attend evaluation. Of the ninety-one patients recalled, 18 had had their prostheses revised (19 knees). 63% of prostheses had survived 10 years or more. Of the patients with St Leger knees in situ (99 knees) the American Knee Scores showed 78% poor, 10% fair, 6% good and 6% excellent results. Radiological assessment identified 12 arthroplasties that had failed (5 femoral components, 5 tibial components and 4 patellae,) 58 that needed close follow up (18 femoral components, 31 tibial components and 38 patellae) and 29 that were well fixed. A best-case Kaplan-Meier cumulative survivorship was 87% at 10 years. (Worst-case was 71% at 10 years). These 10 year results showed that the St Leger total knee prosthesis did not perform as well as other bicondylar prostheses of the same generation and had a higher revision rate. Despite favourable published mid-term results, the long-term results for the St Leger total knee replacement have shown it to be unreliable and not worth the initial financial saving

Aims

Hip disease is common in children with cerebral palsy (CP) and can decrease quality of life and function. Surveillance programmes exist to improve outcomes by treating hip disease at an early stage using radiological surveillance. However, studies and surveillance programmes report different radiological outcomes, making it difficult to compare. We aimed to identify the most important radiological measurements and develop a core measurement set (CMS) for clinical practice, research, and surveillance programmes.

Recently, new metallurgical techniques allowed the creation of 3D metal matrices for cementless acetabular components. Among several different products now available on the market, the Biofoam Dynasty cup (MicroPort Orthopedics® Inc., Arlington, TN, USA) uses an ultraporous Titanium technology but has never been assessed in literature. Coping with this lack of information, our study aims to assess its radiological osteointegration at two years in a primary total hip arthroplasty and compares it to a successful contemporary cementless acetabular cup.

This monocentric retrospective study includes 96 Dynasty Biofoam acetabular components implanted between March 2010 and August 2014 with a minimum 2 years radiographic follow-up. Previous acetabular surgery, any septic issue or re-operation for component malposition were exclusion criteria. They were compared to 96 THA using the Trident PSL matched for age, gender, BMI and follow-up. Presence of radiolucencies and sclerotic lines were described on AP pelvis views using the classification of DeLee and Charnley

There was no statistical difference between the two groups concerning demographics and mean follow-up (p> 0.05). Shell's anteversion was similar but inclination was greater in the biofoam group (p=0.006). 27,17% of the Biofoam shells presented radiolucencies in 2 zones or more and 0% of the Trident shells. 11,96% of Biofoam cups showed radiolucencies in the 3 zones of DeLee comparing to 0% of the Trident cups. There was no statistical difference between the Biofoam group (n=54/96) and the Trident PSL group (n=57/96) in pre-operative functional scores for both WOMAC subscales and SF-12. When evaluating last follow-up PROM's, no significant differences were found comparing the entirety of both groups, 56 Biofoam and 51 Trident PSL. No difference was found either when comparing Biofoam patients with ³ 2 zones of radiolucencies (n=15) to the whole Trident group (n=51).

This study raises concerns about radiologic evidence of osteointegration of the Biofoam acetabular cup. Nevertheless, these radiological findings do not find any clinical correlation considering clinical scores. Thus, it may question the real meaning of these high-rated radiolucencies, which at first sight reflect a poorer osteointegration. The first possible limitation with this study is an overinterpretation of the radiographs. Nevertheless, both observers were blinded regarding the patients groups and clinical outcomes and there was a strong inter-observer reliability. Although both cohorts were matched on their demographics and were similar on the cup anteversion, we noticed a slightly lower abduction angle in the Biofoam population. It could reduce the bone-implant coverage area and hence hinders the bony integration, but this difference was small and both groups remained in the Lewinneck security zone. Furthermore, even if patients were matched on age, gender, BMI and follow-up, other variables can influence early osteointegration (smoke status, osteoporosis) and have not been controlled even though we have no reasons to think their distribution could differ in the 2 groups.

The real clinical meaning of these findings remains unknown but serious concerns are raised about the radiographic osteointegration of the Dynasty Biofoam acetabular components. Concerns are all the more lawful that this implants aim to enhance osteointegration.

Stand-alone anterior lumbar interbody fusion (ALIF) provides the opportunity to avoid supplemental posterior fixation. This may reduce morbidity and complication rate, which is of special interest in patients with reduced bone mineral density (BMD). This study aims to assess immediate biomechanical stability and radiographic outcome of a stand-alone ALIF device with integrated screws in specimens of low BMD.

Eight human cadaveric spines (L4-sacrum) were instrumented with SynFix-LR™ (DePuy Synthes) at L5/S1. Quantitative computed tomography was used to measure BMD of L5 in AMIRA. Threshold values proposed by the American Society of Radiology 80 and 120 mg CaHa/mL were used to differentiate between Osteoporosis, Osteopenia, and normal BMD. Segmental lordosis, anterior and posterior disc height were analysed on pre- and postoperative radiographs (Fig 1). Specimens were tested intact and following instrumentation using a flexibility protocol consisting of three loading cycles to ±7.5 Nm in flexion-extension, lateral bending, and axial rotation. The ranges of motion (ROM) of the index level were assessed using an optoelectronic system.

BMD ranged 58–181mg CaHA/mL. Comparison of pre- and postoperative radiographs revealed significant increase of L5/S1 segmental lordosis (mean 14.6°, SD 5.1, p < 0.001) and anterior disc height (mean 5.8mm, SD 1.8, p < 0.001), but not posterior disc height. ROM of 6 specimens was reduced compared to the intact state. Two specimens showed destructive failure in extension. Mean decrease was most distinct in axial rotation up to 83% followed by flexion-extension.

ALIF device with integrated screws at L5/S1 significantly increases segmental lordosis and anterior disc height without correlation to BMD. Primary stability in the immediate postoperative situation is mostly warranted in axial rotation. The risk of failure might be increased in extension for some patients with reduced lumbar BMD, therefore additional posterior stabilization could be considered.

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The current standard of practice following knee arthroplasty is to demonstrate the appropriate alignment of knee replacements using knee radiographs. Recent studies have suggested that standard knee radiographs provide adequate accuracy for tibial prosthesis alignment assessment as compared with long knee view radiographs which are more technically demanding and carry greater radiation exposure. In this study, we aim to address whether alignment measured on standard knee radiographs are reliable and reproducible over time.

We examined a cohort of 80 patients 37 male (46%), 43 females (54%), mean age = 68 years) who underwent total knee arthroplasty (TKA). Standard knee anteroposterior radiographs performed within 2 days following surgery were compared to standard knee anteroposterior radiographs taken 1 year following the surgery in patients with well-functioning prosthesis. Tibial prosthesis alignment angles between the longitude of the tibial shaft and the tibial baseplate were calculated using Centricity Enterprise Web V3.0 software. The data was examined using R software.

In well-functioning primary knee arthroplasties, tibial prosthesis alignment angles measured in the 1-year follow-up standard view knee radiographs were found to deviate from measurements obtained with the same radiographic specifications in the immediate post-operative period. A significant mean percentage difference was found between the two radiographs.

Long knee view radiographs may be required in order to accurately assess tibial prothesis alignment following total knee arthroplasty.

Total Elbow Replacements are indicated for pain and disability in patients with rheumatoid and osteoarthritis of the elbow. The quality of the cementation has been specifically studied and shown to be directly related to the clinical outcome and implant survival.

A new method of demonstrating sagittal laxity in the anterior cruciate-deficient knee is described. Seventy such knees were compared to 70 normal knees. Sagittal laxity was recorded as the average displacement of the medial and lateral femoral condyles. This displacement index was significantly different between the two groups of knees (P less than 0.0001). A range for normal and abnormal knees is discussed. Quantitative assessment of the degree of sagittal laxity by clinical evaluation is shown to be unreliable. Only the pivot-shift test demonstrated any significant correlation with the amount of sagittal displacement (P less than 0.05).

Background

Implant stability and is an important factor for adequate bone remodelling and both are crucial in the long-term clinical survival of total hip arthroplasty (THA). Assessment of early bone remodelling on X-rays during the first 2 years post-operatively is mandatory when stepwise introduction of a new implant is performed. Regardless of fixation type (cemented or cementless), early acetabular component migration is usually the weakest link in THA, eventually leading to loosening. Over the past years, a shift towards uncemented cup designs has occurred. Besides the established hydroxyapatite (HA) coated uncemented cups which provide ongrowth of bone, new uncemented implant designs stimulating ingrowth of bone have increased in popularity. These cups initiate ingrowth of bone into the implant by their open metallic structure with peripheral pores, to obtain a mechanical interlock with the surrounding bone, thereby stabilising the prosthesis in an early stage after implantation. This retrospective study assessed bone remodelling, osseointegration and occurrence of radiolucency around a new ingrowth philosophy acetabular implant.

Previous work has demonstrated vulnerability of the femoral nerve to damage by anterior acetabular retractors during THA. The aim of this study was to quantify the proximity of the femoral nerve to the anterior acetabulum, on cadaveric material and MRI studies.

A standard posterior approach to the hip was carried out in 6 fresh frozen cadaveric hemipelves. Following dislocation and removal of the femoral head, measurements were taken from the anterior acetabular lip to the posterior aspect of the femoral nerve as it passed over this point. 14 MRI studies of the hip were obtained from the local PACS database (7 male, 7 female; mean age 58 (range 32–80)). T1 weighted axial scans were reviewed. Measurements were obtained from the anterior acetabular lip to the posterior surface of the femoral nerve and artery, and the cross-sectional area of iliopsoas was calculated.

There was no significant difference between the mean distances to the femoral nerve in the cadaveric (24 mm) and MRI groups (25.3mm) (p=0.7). On MRI images, the distance between the acetabular wall and both the femoral artery (p=0.003) and femoral nerve (p=0.007) was significantly larger in men. The femoral artery is strikingly close to the acetabulum in females, passing a mean distance of 14.8 mm, whereas in males this was 23.9 mm. The mean femoral nerve distance was 28.7 mm in males and 21.9 mm in females. The cross-sectional area of iliopsoas was significantly smaller in women (5.97 cm² compared to 11.37 cm², p<0.001).

Both the femoral artery and nerve run in close proximity to the anterior acetabular lip. Care should be taken when placing instruments in this area to avoid neurovascular injury. The increased incidence of femoral nerve damage in women following THA may be due to the significantly smaller bulk of iliopsoas.

Introduction

Pelvic and acetabular injuries are relatively rare and surgical reconstruction usually occurs only in specialist centres. As part of their work up there is a local protocol for radiological investigations including Judet oblique views for acetabular fractures, pelvic inlet and outlet for pelvic ring fractures and urethrograms for sustaining anterior pelvic injury. The aim of this service evaluation was to assess whether patients had these radiological investigations prior to transfer.

Purpose: We searched to define a fracture index useful for predicting the risk of bone fracture in children with essential bone cysts.

Material and method: We reviewed 96 children with an essential bone cyst. The following clinical data were recorded: age, cyst localisation, circumstances of diagnosis.

The radiological analysis was based on 193 AP and lateral x-rays. We measured: 1) the distance separating the superior pole of the cyst from the suprajacent growth cartilage, 2) the largest cyst diameter, 3) the greatest cyst height, 4) the thinnest cortical width facing the cyst, 5) the cyst surface area calculated exactly using surface area software and expressed as a a ratio of shaft diameter (S/d2, Kaelin index). These different parameters were compared for cysts associated with fracture or not.

Results: Mean age at diagnosis was 10.4 years (range 2 – 12.8 years). Most of the cysts were located in the upper portion of the humerus (72%). Fracture was the inaugural sign in 68% of the cases.

Comparing the two cohorts of patients demonstrated that the following differences were significant (Student’s t test): 1) cyst width (p=0.0038): below 16 mm none of the cysts fractured. For wider cysts, there was no difference between the fracture and non-fracture cysts. 2) cortical thickness (p=0.0002); cortical thickness greater than 5 mm protected against fracture. If the cortical measured less than 3 mm, the risk of fracture was greater than 50%. 3) Kaelin index: (p< 0.0001) was directly correlated with fracture risk but no cutoff could be identified.

For an 80 – 100% risk of fracture, the cyst must have the following characteristics: width > 30 mm, height > 75 mm, cortical thickness < 2.4 mm, Kaelin index > 5.

For a 50% risk of fracture, the cyst must have the following characteristics: width > 24 mm, height > 55 mm, cortical thickness < 3 mm, Kaelin index > 3.

Conclusion: The Kaelin index is reliable but difficult to calculate in the consultation setting. Cortical thickness is a good indicator. Its predictive value can be improved by correlating the height of the cyst with its width. These measure can be obtained easily during consultation.

Aims: The purpose is to assess the risk of spinal cord compression in patients with spine metastases using radiological data. Methods: We evaluate 103 patients with the thoraco-lumbar vertebral body metastases Ð 52 with neurological symptoms of spinal cord compression and 51 symptoms free. We measured the statistical relation between spinal cord compression, pathological fracture, angle deformity of the spine and metastasis location. We divide spine into 3 columns and named pediculum as the fourth. We used statistical multiple regression analysis. Results: The risk of spinal cord compression is depended on the location of the metastasis in vertebral body (p< 0,01). We found spinal cord compression symptoms in 25 out of 31 patients in group with pediculum involvement and in 27 out of 72 in group with other locations. It was highly statistically important (p< 0.001). In 45 out of 68 patients with vertebral fractures we found spinal cord compression symptoms (p< 0.01). We did not found statistical correlation between angle deformity and compression symptoms. Conclusions: Compression risk is higher if the metastases are localised in thoraco-lumbar part of spine and if the pediculum is involved. The pathological fracture increases the risk of the compression, too.

Introduction: Tantalum Monoblock Acetabular cup was designed to reduce backside wear and stimulate osseo-integration of cup with bone. The cup has peripheral fit to improve the initial stability and further stability and longevity depends on the osseointegration of cup with acetabulum. The revision cup was intended to give added stability with screws in case of defective rim or large acetabulum. The aim of this study is to assess the radiological outcome following tantalum monoblock revision cup in total hip replacement.

Methods: Between 1999 and 2000, 32 Tantalum mono-block revision acetabular cups was used in 31 patients. Standard hip radiographs were performed during post op, at three months, six months and then annually. X rays were assessed for loosening in De Lee and Charnley zones and for migration of cup.

Results: At a minimum follow-up of 2 years (range 2 to 5 years), 31 hips in 30 patients were assessed. The average age of the patient was 62.4 years (39–78 years). Three Brookers type 1 and one type 2 heterotrophic ossification was seen. There was a gap of 2–5mm in Zone 1(6 patients), 1–5mm in Zone 2 (8 Patients) and 5mm in Zone 3 of one patient. At final follow up, all the gaps were filled, except for one, where 5mm gap was persistent. There was no migration of cup or problems with screws. All the patients were satisfied with the operation.

Conclusion: Short term radiological result following uncemented revision tantalum monoblock acetabular cup in total hip replacement is highly encouraging. However, similar results from other centres and long term follow up studies are necessary to confirm the efficacy of the revision cups.

Anterior decompression and adequate spine fixation in patients with cervical radiculopathy and myelopathy are essential for functional restoration of cervical spine. In this study, we performed evaluation and comparative radiological assessment of several types of spinal implants in terms of bone block formation, sagittal alignment and effectiveness as a structural support.

Materials and Methods: From 1993 to 2003, 165 patients with radiculopathy and myelopathy due to degenerative disease of cervical spine were operated on. The age of patients was 32–74 years (mean age 57, 8). The interbody fusion was performed by several methods.

Group1. Autograft – 91 patients

Group 2. TiNi alloy cages – 74 patients.

Group 3. Varilift expandable cages without plate fixation – 22 patients

Group 4. Verilift cages with plate fixation – 8 patients

Group 5. Bone substitute spacer and plate fixation – 3 patients.

Results: In groups 1 and 2, the bone and bone-metal block was formed during the first 3–4 months after surgery in all patients. There were no cases of bone resorbtion around the TiNi cages or loosening of the device. In patients with one-level (15 patients) interbody fusion by Varilift cages (group 3); formation of the bone block during the same time period was observed in 14 out of 15 patients. In cases with two-level fusion (7 patients), the bone block at the second level was not formed for longer than 6 months. There were 7 cases of subsiding and segmental kyphosis. In group 4, we did not detect any cases of loosening, subsiding or segmental kyphosis. In group 5, no bone block formation was observed after 6 months despite plate fixation.

Conclusions: A high fusion rate was achieved after a single or multi-level discectomy and interbody fusion by autograft and TiNi cages, which did not subside due to their design and superelasticity and can therefore be used without plate fixation. Varilift cages were also very effective, but if used without plate fixation may be associated with subsiding effect. The use of the bone substitute spacer is questionable in cervical spine surgery. Cervical plate fixation is effective as a prophylactic measure against segmental kyphosis in all types of interbody fusion.

Aims: To compare objective and subjective methods of assessment of outcome following total knee replacement. Methods: A retrospective review of 560 consecutive total knee replacements, performed under the care of a single surgeon, between January 1990 and January 2000, on 456 patients, was carried out. Minimum follow-up was two years. The patients were assessed using two postal questionnaires, a clinical interview and examination and a radiological investigation. The results from each assessment were entered into a database and evaluated. Results: The results from the postal and direct questionnaires were comparable. These results correlated well with clinical and radiographic evaluation. A simply worded questionnaire was found to be more user- friendly than a complex questionnaire. Questions about specific daily activities were less user-friendly than questions about general function. Conclusions: A simple postal questionnaire provides an accurate reflection of outcome after total knee arthroplasty. This has significant implications with regard to cost and clinical time when planning follow-up after knee replacement.

Aims: Remaining bone stock at revision total hip arthroplasty (THA) determines the procedure and is related to outcome. This study was carried out to determine the radiological effect on bone stock of patients waiting for surgery. Methods: The hospital notes and AP pelvic radiographs of all (19) patients (22 hips) who underwent revision surgery for symptomatic aseptic loosening of a heterogeneous group of THAs over the last 2 years were obtained. The Hahnemann University Hospital (HUH) Classification and Staging System for Revision THA (a purely radiological classification that evaluates both the acetabular and the femoral bone stock, any component instability and sepsis and that correlates well with functional outcome) was used to evaluate bone stock on the initial clinic and the immediate preoperative radiographs. The effect of delay on the planned procedure was also recorded. Results: The average time delay for all patients was 57 weeks. 12/22 hips deteriorated radiologically by an average of 1.3 points (range 1–3) on the HUH Classification. In 7/12 it altered the procedure to be carried out. Conclusions: This preliminary study suggests that a delay to revision hip surgery is associated with a reduction in bone stock and hence potential functional outcome. It can also detrimentally affect the planned procedure. This study reinforces the need for minimal delay in symptomatic patients with aseptic loosening of THA.

Aims

To evaluate the diagnostic characteristics and reliability of radiological methods used to assess scaphoid fracture union through a systematic review and meta-analysis.

Purpose: Knowledge of the radiological axes in the normal lower limb is important for correction and reconstruction surgery. Classically, the femorotibial mechanical axis presents a zero angle on the anteroposterior view, with 3° femoral valgus being compensated by an equivalent tibial varus. Reference data have however been established with questionable methodology because they have been obtained with small selected samples.

Material and methods: We obtained teleradiograms of the lower limbs in 100 healthy volunteers free of any disease of the lower limbs and selected randomly among patients undergoing surgery for trauma or degenerative lesions of the upper limb. The following angles were measured by the same senior surgeon: mechanical femorotibial angle, orientation of the femoral condylar complex in relation to the mechanical axis of the femur, angle between the mechanial axis and the anatomic axis of the femur, orientation of the tibial plateaux in relation to the mechanical axis of the tibia.

Results: Sixty-nine men and 31 woman, mean age 39 years (range 17 – 62 years) participated in this study. The mean mechanical femorotibial angle was 179° (SD 3°, median 179°, range 168°–185°). The mean orientation of the femoral condylar complex in relation to the femoral mechanical axis was 91° (SD 2°, median 91°, range 86°–98°); 17 subjects had the classical value of 93°. The mean angle between the mechanical and anatomic axis of the femur was 6° (SD 1°, median 6°, range 3°–9°); 29 subjects had the classical value of 7°. The mean orientation of the tibial plateaux in relation to the mechanical axis of the tibia was 88° (SD 2°, median 88°, range 82°–84°); 14 subjects had the classical value of 87°.

Discussion and conclusion: The values considered to be normal in the literature only included 15–20% of the subjects in this study. Although there could be a theoretical selection bias in this series, it can be assumed that there is a wide dispersion of “normal” values around the means. The pertinence of this dispersion in clinical practice remains to be established. The question of individualising reconstruction or prosthetic procedures is raised.

The aim of this study was to assess the results of bone ingrowth into the glenoid component of one design of Total Shoulder Arthroplasty (TSA) in which hydroxyapatite (HA) coating of the glenoid baseplate was introduced since 1997.

Glenoid loosening is one of the most important complications of both cemented and uncemented TSA. Between May 1993 and April 1997 over 140 uncemented, porous coated, metal backed glenoid component were used in our Unit. By 1997 it had become clear that a significant number of these glenoid components had developed mechanical loosening and some required revision. We therefore started using an HA coated glenoid component for our TSAs from April 1997.

One hundred and seventy-four shoulder arthroplasty procedures were performed between April 1997 and October 1999 of which 37 were TSAs using the HA coated uncemented glenoid. The indications included osteoarthritis (22), rheumatoid arthritis (nine), revision TSA (three), avascular necrosis (two) and cuff arthropathy with cuff reconstruction (one). The minimum follow-up was 18 months. The X rays were evaluated using the MLS (Migration, Lucent lines, Screw problems) system, which had been developed and reported previously. This system of evaluation has been shown to be reproducible for assessment of glenoid fixation.

There was one case in which the glenoid liner became displaced and had to be replaced. Our early results at a mean FU of approximately 2 years show an improved radiological fixation compared with those glenoids inserted without HA.