Despite the high prevalence of musculoskeletal disorders seen by primary care physicians, numerous studies have demonstrated deficiencies in the adequacy of musculoskeletal education at multiple stages of medical education. The aim of this study was to assess a newly developed undergraduate module in musculoskeletal medicine.

Abduction braces are commonly prescribed following the closed reduction of a dislocated prosthetic hip joint. Their use is controversial with limited evidence to support their use. We have conducted a retrospective review of dislocations in primary total hip replacements over a nine year period and report redislocation rates in patients braced, compared to those who were not. 67 patients were identified. 69% of those patients who were braced had a subsequent dislocation. Likewise 69% of those who did not receive a brace re-dislocated. 33% of patients that were braced dislocated whilst wearing the brace. Bracing was associated with patient discomfort, sleep disturbance, skin irritation and breakdown. Small femoral head size, monoblock femoral components and poor biomechanical reconstruction was prevalent amongst dislocators. Abduction bracing following closed reduction of a total hip replacement is costly(e950), does not prevent redislocation and may be the cause of considerable morbidity to the patient.

Conservative management remains the gold standard for many fractures of the humeral diaphysis with union rates of over 90% often quoted. Success with closed management however is not universal.

Abduction braces are commonly prescribed following the closed reduction of a dislocated prosthetic hip joint. Their use is controversial with limited evidence to support their use. We have conducted a retrospective review of dislocations in primary total hip replacements over a nine year period and report redislocation rates in patients braced, compared to those who were not. 67 patients were identified. 69% of those patients who were braced had a subsequent dislocation. Likewise 69% of those who did not receive a brace re-dislocated. 33% of patients that were braced dislocated whilst wearing the brace. Bracing was associated with patient discomfort, sleep disturbance, skin irritation and breakdown. Small femoral head size, monoblock femoral components and poor biomechanical reconstruction was prevalent amongst dislocators. Abduction bracing following closed reduction of a total hip replacement does not prevent redislocation and may be the cause of considerable morbidity to the patient.

Aim: To evaluate outcomes in humeral shaft fractures treated non-operatively and to identify possible causes for non-union.

Methods: Patients were identified through a manual search of the operating theatre register and all plaster room forms for the period 1/1/02 – 31/12/05. Patient files and radiographs were then examined for factors that might influence rate of non-union.

Results: 45 fractures were identified in 44 patients. 28 of these were treated conservatively with a hanging cast and functional brace. Of these, 11(39.6%) went onto non-union requiring ORIF + bone grafting.

There was a strong correlation between the length of time spent in the hanging cast and a high rate of non-union. The average length of time spent in cast for the non-union group was 48 days as opposed to 30.9days in the group that went onto unite (p=0.0601)

There was a statistically significant correlation between non-union and the radiographic degree of distraction at the time of first application of hanging cast (p=0.016) and also at the six week check (p=0.001).

Other factors associated with a poor outcome were the degree of varus angulation at presentation (p=0.0078), male sex, right humerus, dominant side, older age group, high energy injury, NSAID use, significant co-morbidities and associated injuries.

Conclusions: Our results compares unfavorably with Sarmiento who quotes a non-union rate of 2.5% in patients who are treated on average only 9 days in hanging cast. Our high rate of non-union is associated with a high degree of distraction at time of first application of hanging cast and an extended period of time spent in cast.

Aim: To prospectively compare the quantity of bone removed from the acetabulum in hip resurfacing arthroplasty and uncemented total hip replacements.

Methods: Sixty four patients were prospectively enrolled in the study. We compared 32 birmingham hip resurfacing acetabular components with 32 trident uncemented acetabular cups. To assess the pre-reaming size of the acetabulum, and to allow comparison between acetabular sizes, the size of the femoral head was assessed to the nearest millimetre intraoperatively with the use of a measuring calliper. The reamings from the acetabulum were collected. This bone was then dehydrated and defatted with five washes of acetone followed by five washes of diethyl ether. The bone was then placed in a furnace at 200 degrees Celsius until a consistent dry weight was achieved. The size of acetabular component used was recorded in all cases.

Results: The mean weight of bone removed from the acetubulum of the resurfacing group was 13.79 g. The corresponding mean weight of bone removed from the acetabulum of the total hip replacement group was 11.71g. Using a non-parametric analysis of covariance (ANCOVA) to account for the covariate of acetabular size, regression analysis indicated no evidence of a difference between the mean bone weight removed in the two groups (p-value of 0.57).

Conclusions: Close attention to surgical technique in preparing the femoral head during resurfacing will allow the use of an appropriately small femoral component. If performed accurately this will avoid oversizing the acetabular component and removal of excess bone stock.

Introduction: At the time of revision hip surgery, large bony defects are often encountered. The traditional method of replacing this lost bone is by the impaction bone grafting technique. Vibration is commonly used in civil engineering to improve compaction of aggregate particles and to increase the compressive and shear strengths of the aggregate. Studies on soil mechanics have established that vibration applied to an aggregate results in more efficient alignment of particles and reduces the energy required to impact the aggregate. In this in-vitro study we have developed a novel method of applying vibration to the bone impaction process.

Methods: 60 Bovine femoral heads were cut into quarters and then milled using the Noviomagnus manual bone mill. Fat and blood were then removed using a pulsed lavage normal saline system over a sieve tower. A vibration impaction device was developed which housed two 15V DC motors with eccentric weights attached inside a metal cylinder. A weight was dropped onto this from a set height 72 times so as to replicate the bone impaction process. The bone graft underlying this was thus impacted into a pellet, with or without the aid of vibration. A range of frequencies of vibration were tested, as measured using an accelerometer housed in the vibration chamber.

Each shear test was then repeated at four different normal loads so as to generate a family of stress-strain graphs. The Mohr-Coulomb failure envelope from which the shear strength and interlocking vales are derived was plotted for each test.

Results: Graft impacted with the addition of vibration at 60Hz was significantly more resistant to shearing force than graft impacted without vibration (p< 0.03). Testing at 20 and 40 Hz showed no statistical difference (p=0.62, p=0.42).

Conclusion: Civil engineering principles hold true for the impaction bone grafting procedure. The best frequency of vibration to enhance the mechanical properties of the aggregate is in the region of 60Hz.

We assessed a new knotless anchor system (Opus AutoCuff, ArthroCare Sports Medicine), which was designed to repair torn rotator cuffs. This knotless anchor winches cuff tissue into the bone with a mattress suture that is cinched into place without the need for knots. We reviewed patients who underwent arthroscopic repair with this technique with a minimum follow up of one year. This is prospective study of a consecutive series of the first one hundred patients who underwent arthroscopic cuff repair with the Autocuff system in 2005. Nine were lost to follow-up leaving ninety-one were available for review. All sizes of cuff tear were addressed and in all one hundred and eighty anchors were deployed. There were thirty seven men and sixty seven women with an average age of 69.4 years (range 36–85 years) Follow-up was by clinical assessment, cuff ultrasound and plain radiographs one year after surgery (12–20 months). Pain relief was described as good to excellent in 93% of patients and Constant scores improved by an average of 34 points with 48.5% being good to excellent, 39.4% fair and 12.1% poor. Nine anchors (5%) in eight patients had pulled out at one year, of which three were symptomatic. Suture repair poses varied points of weakness; loose knots, suture attrition and screw toggle all contribute to failure. We have shown that cuff repair by this method appears to be effective up to one year. It is important, however, to spread the tension of the repair with more than one anchor when treating larger tears.

Introduced in 2005, the Opus Magnum (Arthrocare) anchor has been used in our unit for repair of rotator cuff tears. It is a non-screw type anchor which relies on the deployment of wings locked in the subchondral bone. In order to evaluate whether these anchors migrate after implantation we undertook radiographic examination of their placement at intervals. We attempted to assess whether loss of fixation could be secondary to osteoporosis. Between 2005 and 2006, 106 patients (59 female, 47 male) aged 35–84 years (average age 62 years) underwent arthroscopic repair of rotator cuff tears with a total of 229 anchors. A review of radiographs taken at six weeks and 12 months post-insertion was undertaken. Cortical index of the proximal humeral diaphysis was measured from the AP radiograph indicating bone density; this involved measuring humeral width and medullary cavity diameter at a fixed point of 10cm below the greater tuberosity of the humerus. At six weeks follow-up there were no anchor pull-outs seen on radiographs. At 12 months follow-up 10 of the 229 anchors were found to have pulled out of the bone, equating to a failure rate of 4%. Of these seven of the 10 patients were asymptomatic. The average cortical index was found to be significantly lower in the failure group. Bone quality at the greater tuberosity of the humerus can be insufficient to withstand the tensions developed in newer anchor technology, leading to anchor migration. We present evidence that radiographs may be sufficient to influence the clinician’s choice of anchorage device. An economic estimation of bone density would be a helpful predictor of pull-out strength of suture anchors, essentially a low cortical index would indicate that these anchors are more likely to fail. A routine radiograph at 12 months would also identify the asymptomatic anchor failures.