Introduction

This study was performed to investigate the efficacy of steroid and local anaesthesia (LA) in reducing post-operative pain in lumbar discectomy.

Introduction: Traditionally the fixation of choice as recommended by the AO ASIF group for transverse fractures of the Olecranon and the Patella is the tension band wiring technique.

The concept of tension band wiring is based on the fact that the distractive force applied to one surface of the bone will result in compression on the opposite articular surface.

Clinical outcomes of TBW are not equivocal. It is associated with significant morbidity such as non union, failure of fixation, especially in osteoporotic bone and infection which sometimes leads to amputation. Often a second procedure for removal of prominent metal work is required.

In our biomechanical study we investigated this concept as we believe that the forces generated by TBW construct do not generate significant compressive forces required for healing of fracture.

Materials and Methods: We used 4th generation composite bones (Sawbones^®, Malmoe, Sweden.). These bone analogues have been validated to closely simulate human bone characteristics for fracture toughness, tensile strength, compressive strength, fatigue crack resistance and implant subsidence.

The advantage of using 4th generation composite bone model is that it provides uniformity which is not achievable in cadaveric studies. Two different bone models representative of Olecranon and patella were used. Transverse fractures were created in the bones and fixed with TBW technique as described in A.O. manual.

Two 0.062-inch Kirschner wires and figure of eight configuration of 18G Stainless steel wire with single knot technique was used. Micro motion transducers (DVRT: MicroStrain, Williston, Vermont) with an accuracy of ± 1μm were placed across the fracture site both anteriorly and posteriorly. Continuous information regarding fracture distraction and compression, as determined by the transducers was recorded from both sites simultaneously during the experiment.

The tension band wire construct was loaded up to a maximum force of 4000 Newtons for patella and 500 for the olecranon. The fractures were subjected to cyclic loading at 1Hz using a servo hydraulic materials-testing system (model 8500; Instron, Canton, Massachusetts). The results were analysed on a computer and statistical analysis performed.

Results: During the application of cyclical loading, we noted a gap at the articular surface ranging from 1.1± 0.4mm and 2.1± 0.6mm for Olecranon and patella constructs respectively. During most of the duration of the experiment no transducer displacements were recorded at the articular surface.

Conclusion: The concept that distractive forces at one end could be converted to compression at the other end through the TBW does not hold true in our biomechanical study. A simpler construct may suffice for fixation of patellar and Olecranon fractures which can reduce the complications associated with TBW fixation.

Introduction: This study is performed to investigate the efficacy of steroid, local anaesthesia (LA) or combination of both in reducing post operative pain in lumbar discectomy.

Materials and Methods: The study was ethically approved. Patients undergoing primary single level lumbar discectomy were randomised by a closed envelope system into 4 groups of 1ml of steroid and 1ml of LA, 1ml of steroid and 1ml of saline, 1ml of LA and 1ml of saline and 2mls of saline as control. 10mg of adcortyl in 1ml and 1ml of 0.5% marcaine were used. Combinations of above were applied topically over the nerve root prior to closure. Preoperative, day 1 and eight weeks post operative visual analogue pain score were recorded. 10cm visual analogue pain score chart was used. 24 hours post operative opiate analgesia requirements and duration of inpatient stay were recorded. Data was analysed using Student t-test and Fisher exact t-test.

Results: No significant differences seen in the mean pre operative pain score between all groups. Mean Day 1 post operative pain and analgesia requirement in steroid and LA, steroid only, LA only and control group were 0.9, 2.5, 2.1 and 3.3 respectively. Mean opiate analgesia requirement 24 hours post operatively were 32.4mg, 54mg, 32.4mg and 56.8mg respectively. Mean inpatient stay were 2.2day, 3.91day, 4.62day and 3.63day respectively. At 8 weeks post operatively, no significant differences in the pain score in all groups.

Conclusions: Significant post operative pain reduction was achieved in the steroid and local anaesthesia group compared with other groups (p< 0.05). The results are reflected as well in significant reduction in the post operative analgesia requirement (p< 0.05) and the significant reduction in inpatient stay. (p< 0.05) We recommended the use of perioperative steroid and LA infiltration in lumbar discectomy. Improved post operative pain control reduces post operative opiate analgesia requirement and reduced inpatient stay.

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.

Spinal injuries are among the most devastating injuries related to recreational sport. There are few studies specifically on spinal injuries in horseback riding. The purpose of our study was to determine the factors contributing to horse-riding accidents and to assess the usefulness of wearing protectors while horse riding.

All patients with spinal injuries admitted to our unit over a six-year period (1993–1998) were reviewed. Of 957 patients admitted to the National Spinal Injuries Unit from 1993–1998, 25 patients incurred spinal injury while horse riding. Age, sex, occupation and injury details were collected for all patients. All 25 patients were also contacted retrospectively to collect further details in relation to the specifics of the horse-riding event.

There were 16 male and 9 female patients with a mean age of 35 years (range 17–61). There were nine cervical fractures/dislocations, eleven thoracic fractures, and eight lumbar fractures. Four patient sustained injuries at more than one level. In relation to spinal cord injury, two patients had complete neurological deficit, a further ten had incomplete lesions. Thirteen patients had no neurological deficit. Surgical intervention was required in eleven patients.

Only six riders, all of who were either jockeys or horse trainers, wore back protectors. Of the 19 patients without a back protector there were 5 cervical, 10 thoracic and 6 lumbar injuries. Two patients sustained injuries at more than one level. However, of the six riders wearing a protective jacket there was a completely different fracture pattern level with 4 cervical injuries, only one thoracic injury and on e lumber injury.

The variation in injury level between the group wearing protective back supports and those without is noteworthy. While the numbers are too small to draw a significant conclusion it would appear that there is a trend for riders wearing a back protector to suffer less thoracic and lumbar injuries relative to cervical injuries.

Aim: To investigate the possibility of using polymethylmethacrylate (PMMA) bone cement as a delivery vehicle for anti-tumour chemotherapy.

Methods: Doxorubicin was incorporated into PMMA pellets and incubated in physiological medium at 37°C. Release of Doxorubicin from the pellets continued for eight weeks as demonstrated by high performance liquid chromatography (HPLC).

Doxorubicin-containing pellets were incubated with sarcoma cultures at 37°C for 24 hours. A significantly higher cell death rate(as measured by flow cytometry) was seen in the plates exposed to Doxorubicin compared to those exposed only to plain PMMA, indicating that the Doxorubicin released from the cement pellets retained its cytotoxic capability.

PMMA-Doxorubicin cement pellets were implanted in rat tibiae and the animals killed at intervals over three weeks. HPLC analysis showed that this technique produced high concentrations of Doxorubicin adjacent to the implant but negligible systemic levels(heart, kidney, lung, liver).

Four groups of rats had sarcomas established in their tibiae and then treated either by excision of tumour and Doxorubicin/PMMA implantation, excision and plain PMMA implantation, excision only or no treatment. The animals were then observed for tumour regrowth. A survival advantage was demonstrated for those animals treated by tumour excision and Doxorubicin/PMMA implantation.

Conclusion: These experiments demonstrate that PMMA is an effective medium for the delivery of cytotoxic chemotherapy. This method has scope for early translation to the human situation.