Autologous osteochondral transplantation (AOT) is an effective treatment for large Osteochondral Lesions of the Talus (OLT), however little is reported on an athletic population, who are likely to place higher demands on the reconstruction. The aim is to report the outcomes of large OLT (>150mm²) within an athletic population. The study population was limited to professional or amateur athletes (Tegner score >6) with an OLT of size 150mm² or greater. The surgical intervention was AOT with a donor site from the lateral femoral condyle. Clinical outcomes at a minimum of 24 months included Return to Sport, VAS and FAOS Scores. In addition, graft incorporation was evaluated by MRI using MOCART scores at 12 months post-surgery. 38 athletes including 11 professional athletes were assessed. Mean follow-up was 46 months. Mean lesion size was 249mm². 33 patients returned to sport at their previous level and one did not return to sport (mean return to play 8.2 months). Visual analogue scores improved from 4.53 pre-operatively to 0.63 post-operatively (p=0.002). FAOS Scores improved significantly in all domains (p< 0.001). Two patients developed knee donor site pain, and both had three osteochondral plugs harvested. Univariant analysis demonstrated no association between pre-operative patient or lesion characteristics and ability to return to sport. However, there was a strong correlation between MOCART scores and ability to return to sport (AUC=0.89). Our study suggests that AOT is a viable option in the management of large osteochondral talar defects in an athletic population, with favourable return to sport levels, patient satisfaction, and FAOS/VAS scores. The ability to return to sport is predicated upon good graft incorporation and further research is required to optimise this technique. Our data also suggests that patients should be aware of the increased risk of developing knee donor site pain when three osteochondral plugs are harvested.

Background

Several studies have shown that Staphylococcus aureus (S.aureus) nasal colonization is associated with postoperative surgical site infection and that preoperative decolonization can reduce infection rates. Up to 30% of joint replacement patients have positive S.aureus nasal swabs and patient risk factors for colonization remain largely unknown. Many joint replacement patients continue to undergo surgery without being screened.

Introduction

The objective of this study was to determine if a synthetic bone substitute would provide results similar to bone from osteoporotic femoral heads during in vitro testing with orthopaedic implants. If the synthetic material could produce results similar to those of the osteoporotic bone, it could reduce or eliminate the need for testing of implants on bone.

Lateral hip pain is a common problem in middle-aged females. After investigation, a group of patients remain who are given the diagnosis of ‘trochanteric bursitis’. Treatment to date has included physiotherapy, non-steroidal anti inflammatory medication and judicious use of a combined corticosteroid and local anaesthetic preparation injected into the bursa with or without imaging control. Some surgical procedures have been described. The aims of this study are to document and describe our experience with 88 patients and to raise awareness of the condition as a common cause of lateral hip pain which is amenable to surgical repair.

This study has the approval of the Western Sydney area health service. Between 2000 and 2008, 161 patients were referred to the senior author for management of lateral hip pain. 121 patients underwent surgery to repair a gluteal tendon detachment. 32 patients were excluded from the study due to concurrent or previous surgery to the area. A surgical audit was performed on the remaining 88 patients.

Assessment was performed using the Merle d’Aubigne and Postel scoring system. The average duration of symptoms was 6 – 144 months. At 6 months, 88% patients had minimal or no pain. There were also significant improvements in range of motion and ability to walk. The most significant complication was deep vein thrombosis (6%).

Based on our experience, any patient who does not respond to treatment for trochanteric bursitis should be investigated for a gluteal tendon tear. Those with a positive MRI scan of the trochanteric region can be offered surgery for gluteal tendon repair.

Surgical treatment is considered for treatment of plantar fasciitis in the 10% of patients who do not improve with large range of non-operative measures. The aim of this study is to describe a surgical technique that maintains normal foot mechanics by preserving the integrity of plantar fascia and to demonstrate its effectiveness in the treatment of severe plantar fasciitis unresponsive to no-operative treatment.

The study is a retrospective-prospective analysis of patients who underwent surgery for plantar fasciitis unresponsive to at least 6 month of non-operative measures. The surgical technique involves excision of the heel spur if present, drilling of the calcaneus and a split of the plantar fascia in line with its fibres taking great care not to detach it from its calcaneal attachment. The clinical outcome was assessed prospectively using the Foot and Ankle Ability Measure which is a self-reported questionnaire used to assess the effectiveness of treatment in ankle and foot disorders.

Between 1993 and 2007, 52 patients (56 feet) had surgery for plantar fasciitis. There were 35 females and 17 males and the average age at surgery was 51. Retrospective data was available on all patients. No patients had prior surgery for their symptoms. Of 52 patients treated, 34 were able to be contacted at an average of 46 months after surgery. The average FAAM score was 93 (maximum of 100, 95%CI, 89, 97) and 80% of patients reported a normal or nearly normal overall level of function with no reports of a severely abnormal level of function. Two patients reported no change in symptoms after the surgery. All other patients reported they were satisfied with the outcome of surgery. No patient reported recurrence of symptoms or further surgery for plantar fasciitis. The early postoperative complications were superficial cellulitis (2 patients), wound breakdown (3 patients) and deep vein thrombosis (1 patient). The only long term complication was hypoaesthesia around the surgical scar (8 patients) with no adverse impact on the final outcome.

Plantar fascia release or division has been associated with altered foot biomechanics which may be responsible for forefoot fractures and medial and lateral column foot pain sometimes described after this procedure. Our surgical technique avoids these problems by preserving the integrity of plantar fascia and at the same time is very effective in relieving the symptoms of chronic and severe plantar fasciitis.

Introduction: Therapeutic bone marrow transplantation has increased survival in Hurler syndrome, but the effects on musculoskeletal development remain unclear. Long term reports on mobility are poor, with many patients gradually losing walking ability in later childhood secondary to hip subluxation and joint contractures. As previous cohorts are small, data is limited.

Methods: We detail the follow up of twenty patients over a mean of 94 months (range 1 – 17.4 years). Radiographs were assessed for hip dysplasia using acetabular angle of Sharp, centre edge angle of Wiberg and tibiofemoral shaft angle. Clinical examination was performed at an annual multidisciplinary assessment by one clinician and compared against age matched controls. 3D gait analysis was performed on eight older children, and deviance in kinematic variables was plotted against controls with Mann-Whitney U test for statistical analysis.

Results: All patients demonstrated characteristic ace-tabular dysplasia. Fourteen patients have undergone containment surgery at a mean of 4.4 years. Innominate osteotomy is an essential part of this. Mean preoperative acetabular angle was reduced from 34 ± 4° to 22 ± 3°. Femoral head containment is maintained, with mean centre edge angle in older patients 39 ± 7°. Genu valgum is observed early, and five patients underwent medial epiphyseal stapling at a mean of 7.8 years, decreasing tibiofemoral angle by a mean of 8.0°. All patients are currently independently mobile, with restriction of internal hip rotation being the only significant clinical finding (P< 0.001). Joint contractures were not noted. Walking speed and stride length were comparable to controls, but endurance is reduced by about one quarter. Gait analysis demonstrates a characteristic pattern, with anterior pelvic tilt secondary to thoracolumbar gibbus, relative hip flexion throughout the gait cycle, valgus knees and compensatory pronated feet; all measured deviations were significant (P< 0.001).

Conclusions This large group maintained successful hip containment and good mobility throughout childhood. Innominate osteotomy alone has been used recently. Despite plain film appearance, genu valgum is a functional problem in gait, and we would anticipate greater use of corrective stapling in the future. This is the first report of gait analysis in Hurler syndrome, and features specific to the condition are described.

Aims: Rugby is a popular sport in Ireland, with over 100,000 players registered with the Irish Rugby Football Union (IRFU) at all levels. We report a 10 year series of spinal injuries presenting to the National Spinal Injuries Unit (NSIU) at the Mater Misericordiae University Hospital.

Methods: A large series of spinal injuries in rugby players was isolated utilizing the NSIU database, HIPE and data from the IRFU. An extensive chart review and telephone interview was performed in all cases to determine age, mechanism of injury, possible aetiological factors, anatomic location of injury, American Spinal Injuries Association (ASIA) scores, current level of activity and response to rehabilitation.

Results: From 1994 to 2004, 22 rugby players with spinal injuries necessitated admission to the NSIU. Twelve patients (54%) presented with neurology. The average age at time of injury was 21.1 years (range 14 – 44 years) and all patients were male. The average length of hospital stay was 10.1 days (range 1 – 45 days). Twenty patients had cervical spine injuries. The most common mechanism of injury was hyperflexion of the cervical spine, with C5/C6 most commonly injured. Fifteen injuries occurred at adult level, the remainder at schoolboy level. Seventeen (77%) players were injured whilst playing First Team rugby. Eleven (50%) players were injured in the Backs, the remainder in the Forwards. 68% of injuries occurred in the tackle situation and 32% in the scrums, rucks and mauls. Winger, Full Back and Hooker were the playing positions at greatest risk.

Nine (41%) patients underwent surgery and 11 (50%) required rehabilitation in the National Rehabilitation Centre, Dun Laoghaire, with an average length of inpatient stay of 9.22 months (range 5 – 14 months). Eight (36%) patients felt that their injury was preventable. Of those patients without neurology, 60% have returned to playing rugby.

Conclusion: Rugby as a sporting pastime is not without risk. During the ten year period under review, 8 players suffered permanent disability as a direct result of participation in competitive rugby. Serious spinal injuries continue to occur and recent rule changes have had little effect in reducing their incidence.

Aims: Rugby is a popular sport in Ireland, with over 90,000 players registered with the Irish Rugby Football Union (IRFU) at all levels. We report a 10 year series of spinal injuries presenting to the National Spinal Injuries Unit (NSIU) at the Mater Misericordiae University Hospital.

Methods: A large series of spinal injuries in rugby players was isolated utilizing the NSIU database, HIPE and data from the IRFU. An extensive chart review and telephone interview was performed in all cases to determine age, mechanism of injury, possible aetiological factors, anatomic location of injury, American Spinal Injuries Association (ASIA) scores, current level of activity and response to rehabilitation.

Results: From 1994 to 2004, 22 rugby players with spinal injuries necessitated admission to the NSIU. Twelve patients (54%) presented with neurology. The average age at time of injury was 21.1 years (range 14 – 44 years) and all patients were male. The average length of hospital stay was 10.1 days (range 1 – 45 days). Twenty patients had cervical spine injuries. The most common mechanism of injury was hyperflexion of the cervical spine, with C5/C6 most commonly injured. Fifteen injuries occurred at adult level, the remainder at schoolboy level. Seventeen (77%) players were injured whilst playing First Team rugby. Eleven (50%) players were injured in the Backs, the remainder in the Forwards. 68% of injuries occurred in the tackle situation and 32% in the scrums, rucks and mauls. Winger, Full Back and Hooker were the playing positions at greatest risk.

Nine (41%) patients underwent surgery and 11 (50%) required rehabilitation in the National Rehabilitation Centre, Dun Laoghaire, with an average length of inpatient stay of 9.22 months (range 5 – 14 months). Eight (36%) patients felt that their injury was preventable. Of those patients without neurology, 60% have returned to playing rugby.

Conclusion: Rugby as a sporting pastime is not without risk. During the ten year period under review, 8 players suffered permanent disability as a direct result of participation in competitive rugby. Serious spinal injuries continue to occur and recent rule changes have had little effect in reducing their incidence.

To date the principal focus of the mechanism of cervical spine fracture has been directed towards head/neck circumference and vertebral geometric dimensions. However the role of other measurements, including chest circumference and neck length, in a standard cervical fracture population has not yet been studied in detail. Cervical fractures often involve flexion/extension type mechanisms of injury, with the head and cervical spine flexing/extending, using the thorax as an end point of contact. Thus, the thorax may play an important role in neck injuries.

Study design: We prospectively studied all patients with cervical spine fractures who were admitted to the National Spinal Injuries Unit from 1 July 2000 to 1 March 2001. Anthropometrical measurement of head circumference, neck circumference, chest circumference, and neck length were analysed. Ages ranged from 18 to 55 years, and all patients with concomitant cervical pathology were excluded from the study. Mechanism of injury involved flexion/extension type injuries in all cases; those with direct axial loading were excluded. A control group of 40 patients (age 18–50 years) involved in high velocity trauma with associated long bone fractures, in whom cervical injury was suspected, but who were without any cervical fracture, or associated pathology, were similarly measured.

Results: Our analysis revealed a statistically significant increase in chest size in the male control group versus the male fracture group (97.89 cm versus 94.19 cm, P < 0.05, Student’s t-test). There was a correspondingly significant increase in chest circumference between the female controls versus the female fracture group (92.33 cm versus 88.88 cm, P < 0.05, Student’s t-test). Our results revealed no statistical difference in head circumference, neck circumference, or neck length between each of the groupings. These results indicate a proportionately larger chest may be a protective factor in cervical spine fractures.

Aims: The aim of this study was to investigate the ability of control and degenerate human nucleus pulposis to respond to an exogenous proinßammatory stimulus. Methods: Disc material from patients undergoing surgery for scoliosis, sciatica and low back pain was cultured under basal and lipopolysaccharride (LPS) stimulated conditions using a serumless technique. Levels of IL-1β, TNFα, LTB4, GM-CSF, IL-6, IL-8, MCP-1, PGE2, bFGF and TGFβ-1 in the media were estimated using commercially available enzyme linked immunoabsorbent assay kits. Results: Neither basal nor LPS stimulated control nucleus pulposis (NP) produced detectable levels of IL-1β, TNFα, LTB4 or GM-CSF. LPS induced a significant increase in scoliotic disc IL-8 production, p< .02. LPS induced signiþcant increases in degenerate disc IL-6, IL-8 and PGE2 production, p< .01, p< .001 and p< .005 respectively. LPS signiþcantly increased degenerate disc IL-6, IL-8 and PGE2 production compared to LPS stimulated scoliotic disc, p< .05, p< .02 and p< .003 respectively. Conclusions: Human nucleus pulposus can react to a pro-inßammatory stimulus by secreting IL-6, IL-8 and PGE2, suggesting that the NP may actively participate in the genesis of chemical radiculitis and dis-cogenic back pain.

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.

The Mater Hospital is Ireland’s primary referral centre for spinal injuries receiving 80–90% of all spinal cases annually. In today’s society the number of people competing at more competitive and professional levels is also increasing. Over the years, a lot of work has gone into safety precautions in sport. However despite those improvements our impression was that the incidence of both minor and serious sporting injuries is increasing.

The purpose of this study was to determine the incidence, pattern and mechanism of sports-related spinal injuries in Ireland over the last decade.

Data was collected by performing an audit of the National Spinal Injuries Database from 1994–2001. This database is a prospective computerized database. Data entered relates to the initial presentation, mechanism, level of injury and their acute in-hospital management.

On average 200–220 patients are admitted annually to the National Injuries Spinal Unit. 173 of these were related to sport, which represented 13% of total spinal injuries. 80% are male under 40 years. 29% sustained neurological deficit. The sports responsible for most spinal injuries in Ireland were equestrian (43.8%), followed by rugby (16.4%), diving (15%), GAA (13.6%) and skiing (3%). Rugby injuries were most likely to cause neurological damage. Equestrian accidents commonly caused thoracolumbar fractures while injuries sustained in diving, rugby and GAA were mostly to the cervical spine.

Sport is an important cause of spinal injuries in Ire-land. Coaches and team doctors must be educated about safe practices and emergency management of these terrible injuries and for those unfortunately affected in the prime of their lives adequate rehabilitation resources need to be implemented so as to lessen their economic burden.

Recently there has been considerable interest in the role of inflammatory mediator production by herniated degenerate discs. Modic has described MR endplate changes which have an inflammatory appearance and have been linked with discogenic back pain. To date there has been no biomechanical investigation of discs with associated Modic changes.

The aim of this study is to determine if degenerate discs with associated Modic changes have higher levels of pro-inflammatory mediator production than those without Modic changes.

Intervertebral disc tissue was obtained from 52 patients undergoing spinal surgery for sciatica [40] and discogram proven discogenic low back pain [12]. The tissue was cultured and the medium analysed for interleukin-6, interleukin-8 and prostaglandin E2 using an enzyme linked immunoabsorbetn assay method. Preoperative MR images of the patients were examined by a double blinded radiologist to determine the Modic status of the cultured disc level.

Forty percent of patients undergoing surgery for discogenic low back pain had a Modic 1 change compared to only 12.5% of patients undergoing surgery for sciatica [p< .05] There was a statistically significant difference between levels of IL-6, IL-8 and PGE2 production by both the Modic1 [M1] and Modic2 [M2] groups compared to the Modic negative [NEG] group. IL-6:NEGvM1 p< .001, NEG v M2 p< .05, IL-8: NEG v M1 p< .01, NEG v M2 p> .05, PGE2: NEG v M1 p< 01, NEG v M2 p< .05.

Modic changes have been associated with positive provocative discography by a number of authors. Pain generation requires the presence of nerves and hyperalgsia inducing mediators. Both IL-8 and PGE2 are known to induce hyperalgesia. The fact that Modic changes are associated with high levels of production of these mediators supports their role as an objective marker of discogenic low back pain.

The role of nucleus pulposus (NP) biology in the genesis of sciatica is being increasingly investigated.

The aim of this study was to examine the ability of control and degenerate human nucleus pulposus to respond to an exogenous pro-inflammatory stimulus.

Control disc material was obtained from surgical procedures for scoliosis and degenerate disc tissue from surgical procedures for sciatica and low back pain. Disc specimens were cultured using a serumless technique under basal and lipopolysaccharride (LPS) stimulated conditions and the media harvested, aliquoted and stored at –80°C for subsequent analysis. Levels of IL-1β,TNFα, LTB4, GM-CSF, IL-6, IL-8, MCP-1, PGE2, bFGF and TGFβ-1 in the media were estimated using commercially available enzyme linked immunoabsorbent assay kits.

Neither basal nor LPS stimulated control or degenerate NP produced detectable levels of IL-1β, TNFα, LTB4 or GM-CSF. Control disc IL-8 secretion increased significantly with LPS stimulation, p< .018. Degenerate disc IL-6, IL-8 and PGE2 production increased significantly with LPS stimulation, p< .01, p< .001 and p< .005 respectively. LPS stimulated degenerate NP secreted significantly more IL-6, IL-8 and PGE2 than LPS stimulated control NP, p < 0.05, 0.02 and 0.003 respectively.

LPS induces an increase in both control and degenerate NP mediator production demonstrating the ability of human NP to react to a noxious stimulus by producing pro-inflammatory mediators. The difference in levels of basal and LPS stimulated mediator production between control and degenerate discs show that as a disc degenerates it increases both its level of inflammatory mediator production and its ability to react to a pro-inflammatory stimulus. The increased sensitivity of degenerating human NP to noxious stimuli and increased ability to respond with inflammatory mediator production support the role of NP as an active participant in the genesis of lumbar radiculopathy and discogenic back pain.

The pathophysiology of discogenic low back pain is poorly understood. The morphological changes occurring in disc degeneration are well documented but unhelpful in determining if a particular degenerate disc will be painful or not.

Herniated intervertebral disc tisssue has been shown to produce a number of pro-inflammatory mediators and cytokines. No similar studies have to date been done utilising disc material from patients with discogenic low back pain.

The aim of this study was to compare levels of production of interleukin-6 (IL-6), interleukin-8 (IL-8) and Prostaglandin E2 (PGE2) in disc tissue from patients undergoing discectomy for sciatica with that from patients undergoing fusion for discogenic low back pain.

Tissue from 50 patients undergoing discectomy for sciatica and 20 patients undergoing fusion for discogenic low back pain was cultured and the medium harvested for subsequent analysis using an enzyme linked immunoabsorbent assay method. Statistical analysis of the results was performed using the Mann-Whitney test.

Disc specimens from both experimental groups produced measurable levels of all three mediators. Mean production of IL-6, IL-8 and PGE2 in the sciatica group was 26.2±75.7, 247±573 and 2255±3974 respectively. Mean production of IL-6, IL-8 and PGE2 in the low back pain group was 92±154, 776±987 and 3221±3350 respectively (data = mean production pg/ml ± 1 standard deviation).

There was a statistically significant difference between the levels of IL-6 and IL-8 production in the sciatica and low back pain groups (p< 0.006 and p< 0.003 respectively).

The high levels of pro-inflammatory mediator production found in disc tissue from patients undergoing fusion for discogenic LBP may indicate that nucleus pulposis pro-inflammatory mediator production is a major factor in the genesis of a painful lumbar disc. This could explain why some degenerate discs cause LBP while other morphologically similar discs do not.

Patients with hemiplegic cerebral palsy walk with a well recognised characteristic gait pattern. They also commonly have a significant leg length discrepancy which is less well appreciated. The typical equinus gait in these patients is assumed to be an integral part of the disease process of spasticity and a tendency to develop joint contractures. However an alternative explanation for the presence of an equinus deformity may be that it is a response to the development of a significant leg length discrepancy in these patients. The development of such an equinus deformity would have the effect of functionally lengthening the short hemiplegic leg. We set up a study to examine the correlation between leg length discrepancy and equinus deformity. We reviewed the gait analyses and clinical examinations of 183 patients with hemiplegic cerebral palsy. While 22% had no significant leg length discrepancy, 65% had a measured discrepancy of greater than 1cm. There was a linear correlation between age and limb length discrepancy. We also found that there was a linear relationship between leg length discrepancy and ankle equinus at the point of ground contact. We propose that the equinus deformity seen in the hemiplegic cerebral palsy patient is multifactorial and is related not only to the disease state but also to the presence of leg length discrepancy. The equinus deformity functionally lengthens the short hemiplegic leg. Indeed it may represent an attempt by these patients to functionally equalise their leg lengths. This factor must be taken into account when considering correction of an equinus deformity in patients with hemiplegic cerebral palsy in order to avoid either recurrence of the deformity or the production of functionally unequal leg lengths. We have also highlighted the presence of significant shortening of the hemiplegic leg in these patients.

Dysphagia is said to occur in 2% of patients immobilized in a Halo-Vest for the treatment of cervical injuries. This has been reported to lead to aspiration pneumonia which has a significant mortality rate in the elderly. In our experience dysphagia is a far greater problem than reported and is proportional to the degree of cervical spine extension.

The aim of our study was to ascertain the effect of cervical spine extension on swallowing in normal volunteers immobilized in a Halo- vest.

A halo vest was used to immobilize the cervical spine and to vary the degree of extension in ten volunteers. Videoflouroscopic studies were performed for each volunteer using three consistencies – liquid, paste and biscuit. The study was performed in neutral, 20° and 40° of extension. A subjective rating scale was completed by each volunteer. Videoflouroscopic study were blindly analysed by a radiologist and a speech and language therapist. Fourteen parameters were measured and recorded for each swallow.

Subjectively there was significantly increasing level of difficulty experienced for each swallow. At both degrees of extension there was a significant difference in oral transit time, piecemeal deglutition, Laryngeal penetration (a highly significant risk factor for aspiration), amount of residue occurring at the level of the valleculae and the number of successive clearance swallows compared to control.

In conclusion this study has clearly demonstrated significant impairment in deglutition following halo vest application. This impairment is directly related to the degree of neck extension. These findings should be taken into careful consideration when managing patients in cervical orthoses.

The management of type two odontoid peg fractures remains controversial. The policy in our unit is to initially manage all of these injuries non-operatively. Patients with displaced fractures (0.2mm translation, > 15° angulation) are placed in halo vests followed by fracture reduction under radiological control. Undisplaced or minimally displaced fractures are treated in either custom-made minerva orthoses or halo vests.

We report the results of 42 consecutive cases of type two odontoid peg fractures. There were 24 males and 18 females with a mean age of 53 (range 18–89) years. Twenty-one (50%) of patients were > 65 years of age. In 29 cases the fracture was undisplaced or minimally displaced and in the remaining 13 cases it was displaced (> 2mm translation, > 15° angulation) either posteriorly (extension-type)(6) or anteriorly (flexion type) (7). All displaced cases were treated in halo vests while the remainder were treated in minervas (14) or halo vests (15).

Loss of reduction occurred in nine cases necessitating adjustment in five and C1/2 posterior fusion in four. Of these cases five were displaced extension type-fractures, two required fusion. Pin site infection necessitated early removal of halo vest and conversion to minerva in three cases. In all of these cases fracture union was achieved.

Overall, union was achieved in 37 patients giving a non-union rate of 12%. The mean age of the five non-unions was 42 years with only one patient over 65 years of age. Four of these patients had C1/2 posterior fusions and the remaining patient refused surgery.

Of the 29 patients with displaced or minimally displaced fractures five (17%) required surgery for either non-union (3) or displacement (2), whereas three (23%) of the displaced group required surgery for non-union (1) or displacement (2). All of these were extension type fractures.

We conclude that a policy of non-operative management of these fractures resulted in union in a high proportion of patients of all age groups except for those with extension type fractures. This fracture pattern may warrant primary surgical intervention.

Introduction: Gait initiation is a sequence of stereotypical postural shifts culminating in a forward step. Muscular and gravitational forces interact leading to appropriate dynamic conditions that allow progression. This requires a complicated system of neural and muscular control. Derangement of ground reaction forces during gait initiation may be a more specific indicator of neuromuscular disease than steady state gait.

Little work has been done on gait initiation in children and there is no published data on gait initiation with cerebral palsy. The aim of this study was to examine the ground reaction forces and centre of pressure in normal children during gait initiation, to compare these to similar values in hemiplegic children and to try to identify differences between the two which may be diagnostic for hemiplegia.

Patients and methods: Five normal and five hemiplegic children were studied. Kinematic and dynamic data were collected using a CodaTM motion analysis system and KestlerTM force plate. All subjects stood with one foot on and one foot off the force plate and walked off upon hearing an audible cue. Tests were repeated measuring right and left, normal and hemiplegic legs as both stance and swing legs. Ground reaction forces in the X,Y and Z axes, centre of pressure and kinematic data were collected and studied.

Results: 1) Normal children. In the vertical direction for the stance leg there is an initial fall in GRF, followed by a bimodal peak in GRF. In the fore-aft direction the GRF is initially directed backwards and subsequently has a bimodal forward force.

Medio-laterally the stance GRF tending to adduct falls initially and subsequently rises with a bimodal peak. The forces in the swing leg reciprocate these forces.

2) Hemiplegic children. The overall pattern seen when the normal leg is the stance leg are similar to those in normal children with certain specific variations in force development and magnitude. When the hemiplegic leg is the stance leg the overall patterns are again similar but considerably less smooth with characteristic changes indicative of neuro-muscular disturbance. The initial “adjusting” forces tend to be larger indicating the greater force required for control.

Discussion: The pattern and relative magnitude of forces measured for normal children are identical to those previously reported for adults. This validates our study design and indicates that central programming for gait initiation develops early in life. It is therefore an early developmental skill and may be used as a diagnostic test in childhood. Significant variations are seen in cerebral palsy. Knowledge of these specific changes may allow earlier and more accurate diagnosis of cerebral palsy in children under investigation for movement disorders. Normal GRF patterns during gait initiations may provide early reassurance for parents of children suspected of having cerebral palsy.