Focal femoral inlay resurfacing has been developed for the treatment of full-thickness chondral defects of the knee. This technique involves implanting a defect-sized metallic or ceramic cap that is anchored to the subchondral bone through a screw or pin. The use of these experimental caps has been advocated in middle-aged patients who have failed non-operative methods or biological repair techniques and are deemed unsuitable for conventional arthroplasty because of their age. This paper outlines the implant design, surgical technique and biomechanical principles underlying their use. Outcomes following implantation in both animal and human studies are also reviewed.

Cite this article: Bone Joint J 2013;95-B:301–4.

Introduction: Weber B fractures are one of the most common fractures of the ankle. Unstable fractures are treated with lateral plating and a lag screw. Another method of fixation is antiglide plating, this concept was first introduced by Brunner and Weber in 1982.

Manoli and Schaeffer in 1987, showed that fixation by antiglide plate demonstrated superior static biomechanical properties compared to lateral plating.

However there are some shortcomings in their study and hence we decided to perform our biomechanical study. The shortcomings of the Manoli study are. They did not use an interfragmentary lag screw for lateral plate fixation. It was a cadaveric study where the bone does not accurately represent the live bone. The quality of the bone ranging from normal to osteoporotic bone varies from cadaver to cadaver and hence there is no uniformity between the samples.

Materials and Methods: We used 4th generation composite bone models validated to closely simulate human bone characteristics for fracture toughness, tensile strength, compressive strength, fatigue crack resistance and implant subsidence. 4th generation composite bone model provides uniformity of test samples which is not achievable in cadaveric studies.

These bones were custom made for the experiment. We used two sets of bones, one representative of normal bone (Set A n=10) and the other of osteoporotic bone quality (Set B n=10). Each of the sets A & B will have two types of fixations for artificially created Weber B Fractures.

Lateral plate with interfragmentary lag screw.

The strength of the fixation was measured by restressing the bone until the fixation failed using an Instron machine which simultaneously applied torque and compressive forces to the fibular construct. The resulting data was analysed on a computer and statistical analysis was performed.

Results: When the two fixation constructs were stressed to failure, the lateral plate construct demonstrated less stiffness (3–5Nm/degree) and failed at lower energy levels (250Nm). Similar values obtained for the antiglide system were, stiffness of 12–16Nm/degree and energy absorbed to failure 350–450Nm. Antiglide plating was significantly more stable in the osteoporotic fibula.

Conclusion: Antiglide plating with lag screw is much more stable than lateral plating. It is suitable for treatment without plaster cast post operatively. It results in a more stable fixation in osteoporotic bone.

Introduction: The incidence of osteoporosis is increasing as the population ages. Amongst the recommended treatment modalities for osteoporosis is the use of bisphosphonates. The National Osteoporosis Foundation (U.S.A.) recommends DEXA scanning prior to commencing treatment with bisphosphonate therapy. However, in the Irish setting the availability of DEXA scanning is often limited. We hypothesised that a high percentage of elderly women presenting with fragility fractures of the distal radius (following a simple fall from standing height) had underlying osteoporosis. As such, the initiation of treatment with bisphosphonates prior to obtaining a DEXA scan may be warranted in this patient cohort.

Aim: To assess the incidence of osteoporosis in a continuous cohort of women over 60 years of age presenting with fractures of the distal radius.

Patients and Methods: All female patients aged > 60 years old presenting to the fracture service over a five month period with distal radial fragility fractures were evaluated. Exclusion criteria included:

non-English speakers

100 consecutive patients presenting to the fracture service with distal radial fragility fractures were prospectively identified. Data was collected, including body mass index (BMI), risk factors for osteoporosis, and the OST risk index calculated. A DEXA scan was then performed on the patient’s hips and lumbar spine.

Results: The mean patient age was 74.3 (95%CI + 10.6) years. Mean BMI was 17.3 kg/m2. The mean Osteoporosis Self-assessment Tool (OST) index score was 0.65 correlating with a moderate risk for osteoporosis. The mean T score for the patients’ hips was −2.0 while that for the lumbar spine was −1.7. 64% of patients were osteoporotic with a T score of less than −2.5.

Conclusions A significant incidence of osteoporosis was noted in the study cohort. It is imperative that orthopaedic surgeons recognise the high incidence of osteoporosis in the elderly female population presenting with fragility fractures. The high morbidity and mortality associated with hip and vertebral fractures in this population may be prevented by early treatment of underlying osteoporosis.

Introduction: The increasing popularity of minimal access surgery in orthopaedic surgery has resulted in increasing use of intra-operative fluoroscopy. The radiation dose received by the surgeon varies from procedure to procedure depending on several factors such as duration of procedure, direct exposure to radiation beam and distance from the radiation source. In particular hand and wrist injuries often involve direct fluoroscopic exposure to the hands of the surgeon and assistant during the procedure.

Aim: We undertook a prospective study to directly evaluate the exposure of the surgeon’s and assistant’s hands and thyroid glands during K-wiring procedures of the hand and wrist. In addition we evaluated the efficacy of a lead thyroid shield in limiting the radiation dose to the thyroid gland. In addition we undertook a questionnaire of orthopaedic surgeons and trainees in Ireland to assess the availability of thyroid shields and current practice in wearing them.

Method A total of 30 cases were evaluated. Dosimeter film badges (TLD) were obtained from the Radiological Protection Institute of Ireland (RPI). Two dosimeters were worn by each of the surgical team: one on the dorsum of the dominant hand and a second worn on the neck during the procedure. The number of fluoroscopic exposures, number of times that hands were caught in the image field, the total dosage of radiation for the procedure and the length of time of exposure were recorded. In 20 cases the surgical team undertook standard precautions of a lead jacket. In a random selection of 10 cases the surgical team also wore a thyroid shield.

Results. The mean dose to the surgical teams’ hands was 1.8 cGy (95% CI + 0.6). The mean dose to the thyroid gland was 0.6 cGy in unprotected cases. Notably the dose to the assistants’ hands was higher though this did not reach statistical approval. In cases in which a thyroid shield was worn a significant decrease in dose was noted (p< 0.05). 35% of surgeons had completed a radiation protection course with junior trainees being less likely to have completed such a course.

Conclusion: Significant cumulative radiation dose to the hands and thyroid gland occurs following K-wiring of extremities. The dose to the thyroid gland can be effectively decreased by the use of a thyroid collar. Junior trainees whose operative times and hence radiation exposure are higher, have limited radiation protection training. The mandatory use of thyroid shields and early introduction of radiation protection training may help minimise further radiation exposure.

Introduction: Proximal humeral fractures are common in the elderly osteoporotic population. Surgical management of such fractures with traditional internal fixation techniques is often challenging due to poor bone quality. Fixation with intramedullary devices theoretically offers better fixation, but with increased risk of shoulder pain and decreased range of motion. We undertook a study to compare outcome following fixation of such fractures with either an intramedullary nail (Polarus), standard Clover Leaf plate (AO), or Philos Locking plate (AO).

Method: All patients admitted for surgical management of a proximal humeral fracture were entered into the study. 10 patients were treated using a Philos plate (Group 1), 5 with a Clover Leaf plate (Group 2), and 10 with a Polarus nail (Group 3). Post-operative assessment included radiological evaluation, clinical assessment of range of motion compared to the non-injured arm, assessment of pain severity (visual analogue scale), and functional assessment (DASH score). Non-parametric statistical techniques were used to analyse results.

Results: There was no significant difference in age or sex distribution between the three groups. (Mean ages: Group 1: 54.6 yrs, Group 2: 45.2 yrs, Group 3: 59.7 yrs) Mean patient follow-up was 22 months (range 5–52 months).

All patients in Group 1 and 2 went on to satisfactory radiological and clinical union. A higher complication rate was noted in the Polarus nail group, with 3 patients requiring removal of metal due to soft tissue or subacromial impingement. In addition one patient developed a non-union and required Philos plate fixation.

All groups demonstrated a significant decrease in shoulder range of motion following injury, however this was less marked in Group 1 (Philos plate). In addition, patients in group 1 (Philos plate) demonstrated a more rapid recovery in terms of severity of pain, functional impairment and range of motion in the early postoperative phase. However, no significant long-term difference was noted in terms of post-operative pain or functional deficit between group 1 and 2. The poor outcome in group 3 was associated with a high incidence of shoulder pain and secondary procedures.

Conclusion: Intramedullary fixation of proximal humeral fractures resulted in a high level of complications requiring secondary procedures in many cases. Our study supports the safety and efficacy of plate fixation techniques in the operative management of proximal humeral fractures.

Introduction Magnetic resonance imaging (MRI) is important in non-invasive evaluation of osseous and soft-tissue structures in the post-traumatic knee. However, it is sometimes impossible to determine if a focus of high signal intensity in the meniscus is confined to the substance, or extends to involve the joint surface. This is a critical differentiation as the latter represents menisci tears that can be found and treated arthroscopically, whereas the former represents degradation, intra-substance tears or normal variants not amenable to arthroscopic intervention.

The aim of this study was to investigate occurrence of altered signal intensity in the posterior horn of the medial meniscus and correlate with arthroscopic findings.

Materials and Methods 64 patients with suspected post-traumatic internal derangement of the knee who underwent MRI prior to arthroscopy were evaluated. All patients initially had MR imaging of the symptomatic knee using a standard protocol in a Siemens Symphony 1.5 Tesle Magnetom. MR images were then interpreted and reported by 2 radiologists experienced in MR and skeletal radiology. Meniscal tears were graded according to the system validated by Lotysch. A Grade 3 signal was considered unequivocal evidence of a meniscal tear. Equivocal tears (Grade 2/3 signal) were diagnosed if it was unclear if there was a small portion of normal intact meniscal tissue between a linear high signal in the meniscus and the articular surface abutting the meniscus.

Arthroscopy was subsequently performed by senior surgeons aware of the MR findings within 2 weeks of imaging.

Patients were re-assessed clinically and evaluated functionally at a mean follow-up time of 5 months. Radiographic, arthroscopic and clinical results were then correlated and evaluated.

Results There were 48 males and 16 females in the group, with a mean age of 28.2 years.. Tears of the posterior horn of the medial meniscus were reported on MRI unequivocally (Grade 3 signal) in 18 patients and equivocally (Grade 2/3 signal) in 10 patients. Subsequent arthroscopic correlation revealed 16 tears (89%) in the unequivocal group and only one tear (10%) in the equivocal group.

Discusion The finding that only 10% of patients with an equivocal tear in the posterior horn of the medial meniscus on MRI were subsequently found to have a tear on arthroscopy would suggest that early arthroscopic intervention is not warranted in these cases. We suggest that unless symptoms persist over the course of 3 to 6 months, or if a more compelling symptom complex develops, only then should arthroscopic evaluation be considered.

Conclusion Equivocal tears on MRI of the posterior horn of the medial meniscus have a low rate of arthroscopically detected tears and a trial of conservative therapy may be prudent in such cases.

Currently, data on the complication rates of primary total hip arthroplasty (THA) in Ireland is not available. We surveyed all consultant members of the Irish Orthopaedic Association (IOA) to determine the self reported complication rates of primary THA and analysed national audit data from the Economic and Social Research Institute (ESRI) for 2002. We received an 83% response rate to our survey. 58 surgeons reported data on 5,424 primary THAs for the year 2003. The mean dislocation rate was 1.02% and those using a posterior approach reported a significantly higher dislocation rate (p< 0.05). Deep infection rates were 0.44% and 29% of these were MRSA infections. There was no significant benefit reported from the use of body exhaust operative attire. The mean rate of venous thrombo-embolism (VTE) was 3.5%. There was no statistical difference reported in VTE rates when prophylaxis was commenced pre or post operatively, neither was there any significant benefit reported from using VTE prophylaxis for an extended period beyond the length of inpatient stay, nor from patients wearing graduated compression elastic stockings. ESRI national audit rates for dislocation were 25.7%, and rates of deep infection and VTE were 0.87% and < 0.1% respectively in 2002. Deficiencies in available ESRI data and questionable reliability of self reported rates, underline the necessity for a national Hip Register database in Ireland. The accurate recording of objective data on primary THA could provide an evidence base to improve surgical THA practices and patient outcomes and provide significant healthcare savings.

Magnetic resonance imaging has emerged as an important modality in the non-invasive evaluation of osseous and soft-tissue structures in the post-traumatic knee. However, it is sometimes radiologically impossible to determine with confidence if a focus of high signal intensity in the meniscus is confined to the substance of the meniscus or if it extends to involve the joint surface. This is a critical differentiation because the latter represents menisci tears that can be found and treated arthroscopically, whereas the former represents degradation, intrasubstance tears or perhaps normal variants that are not amenable to arthroscopic intervention.

The aim of this study was to investigate the occurrence of altered signal intensity in the posterior horn of the medial meniscus in correlation with arthroscopic findings.

Sixty-four patients with suspected post-traumatic internal derangement of the knee who underwent magnetic resonance imaging prior to arthroscopy were evaluated retrospectively. There were 48 males and 16 females. Mean age was 28.2 years. Tears of the posterior horn of the medial meniscus were diagnosed unequivocally (Grade 3 signal) in 18 patients and equivocally (Grade 2/3 signal) in 10 patients. Arthroscopic correlation revealed 16 tears (89%) in the unequivocal group and only one tear (10%) in the equivocal group).

A meniscal tear is unlikely when magnetic resonance imaging shows a focus of high signal intensity in the posterior horn of the medial meniscus that does not unequivocally extend to involve the inferior or superior joint surface. An appropriate trial of non-operative treatment is recommended in such questionable cases. Magnetic resonance imaging is a useful diagnostic tool, however, it should be used selectively, and in conjunction with history and clinical examination in evaluating internal derangement of the knee.

Introduction: Articular fractures, especially in weight-bearing joints of the lower extremity, require anatomical reduction for good long-term function. If anatomic reduction is achieved 90% of patients have good results. Accurate anatomical reduction of acetabular fractures is made difficult y the complicated anatomy of the acetabulum and pelvis. Plain films and computerised tomography are very useful in the assessment, classification and planning for surgery of these fractures, but conventional imaging only provides two dimensional images of these fractures. While interpretation of traditional imaging techniques becomes better with experience novel techniques may assist in the understanding of these complex injuries. This project presents the use of three dimensional life size models which can be rapidly manufactured from CT scans to facilitate fracture classification and operative planning.

Patients and Methods: Standard 4 mm CT cuts were reformatted to 2 mm and saved as DICOM files for a series of 15 consecutive patients with complex acetabular fractures (not including isolated posterior wall injuries). These were imported into Mimic (Materialise) data conditioning software, which allowed manipulation and thresholding of images so that a three-dimensional computer model could be built. The data was exported to the Selective Laser Sintering (SLS) system and a life size three-dimensional model constructed. Three consultant orthopaedic surgeons and three senior trainees were asked to classify, using the system of Letournel, each fracture using 1) conventional radiographs (AP pelvis, Judet views and CT scans). 2) Using a model. As no absolute of fracture type was available the Kappa statistic was used to evaluate inter and intraobserver agreement. This compared an observed level of agreement with the level of agreement that would be expected by chance alone.

Results: Interobserver agreement was not absolute using either conventional radiographs or the sintered model. For the consultants the kappa statistic using conventional radiographs was 0.61 while the kappa value using the model was 0.76 (p=< 0.05). For the trainees the kappa was 0.42, using conventional radiographs and 0.71 using the model (p=< 0.01)>

Discussion: The complex three-dimensional anatomy of the pelvis and acetabulum make assessment and classification of fractures of these structures notoriously difficult. The value of accurate fracture classification is well recognised particularly in the treatment of intra-articular injuries. The use of this real life model of a fractured pelvis has been shown in this study to significantly reduce the degree of interobserver variability in the classification of these injuries. This effect is particularly evident for less experienced surgeons.

Conclusion: The technique is available and relatively inexpensive. These models may be of great benefit for preoperative planning, classification and assessment of prognosis in acetabular fractures. Its use should prove invaluable as a tool to aid clinical practice.

Over a period of one year we treated nine fractures of the sesamoid bones of the hallux, five of which were in the medial sesamoid. All patients had symptoms on exercise, but only one had a recent history of injury. The mean age of the patients was 27 years (17 to 45) and there were six men. The mean duration of symptoms was nine months (1.5 to 48). The diagnosis was based on clinical and radiological investigations. We describe a new surgical technique for percutaneous screw fixation for these fractures using a Barouk screw.

All the patients were assessed before and after surgery using the American Orthopaedic Foot and Ankle Society Hallux Score (AOFAS). There was a statistically significant improvement in the mean score from 46.9 to 80.7 (p = 0.0003) after fixation of the fracture with a rapid resolution of symptoms. All patients returned to their previous level of activity by three months.

We believe that this relatively simple technique is an excellent method of treatment in appropriately selected patients.