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.

Background: MRSA is a major economic and health issue in Ireland and as such is of particular importance in the appropriate management of orthopaedic patients. Bone, joint and implant infection can lead to unfavourable outcomes with a long protracted in hospital stay inevitable. The cost for the patient, the hospital and society are substantial. Numerous protocols have been proposed internationally to aid in the management of MRSA infection in orthopaedic patients with pre assessment and ring fencing of patients shown to have a favourable impact.

Aims: To analyse the impact of a series of infection control measures on the infection and prevalance of MRSA in both elective and trauma orthopaedic patients.

Methods: We conducted a prospective study of our unit over three time points from 2005 to 2008. All elective and trauma orthopaedic surgery was based in Merlin Park Hospital up until December 2006. Since then all elective orthopaedic surgery has remained based in Merlin Park Hospital with all trauma surgery being moved to University Hospital Galway and all trauma patients based in an exclusively ring fenced orthopaedic ward. We recorded total rates of MRSA infection and colonisation in all orthopaedic patients over nine months of each year from 2005 to 2008, pre and post separation of trauma and elective services. Of note a pre admission screening protocol was implemented in March of 2006. We also prospectively recorded all MRSA data in patients treated through our ring fenced trauma ward from its opening date in November 2006.

Results: 12259 patients were reviewed between 2005 and 2008. The mean age of all admitted patients was 46 with th emean age of all MRSA positiv epatients being 71(p=0.000). There was no statistical difference for gender distribution between MRSA positive patients, but more women were positive than men.

The rates of MRSA infection for 2005, 2006 and 2007 were 0.49%, 0.28% and 0.24% respectively (binomial comparison, 2005 to 2006, p< 0.005 and 2005 to 2007, p< 0.005). Again when trauma and elective units were seperated there was a corrected rate of infection of 0.14% and 0.33% respectively. In 2005 there was 9 Superficial Incisional (SI), 8 Organ Space Infection(OSI) and 4 Deep Incisional (DI), 2006 had 7 SI, 4 OS and 4 DI and in 2007 there was 9 SI, 9 OS and 1 DI seen in the elective unit There was no Deep MRSA infection seen in the new ring fenced trauma unit. MRSA infection was found to cause a considerable increase in length of stay with normal orthopaedic patients staying a mean of 5 days whilst MRSA patients staying 23.4 days (p=0.000).

Conclusion: The separation of emergency and elective orthopaedic services coupled with effective preoperative screening has resulted in a reduction of MRSA infection and improved patient outcome.

Introduction: Quadriceps femoris (QF) atrophy has been associated with the development of knee OA and is a major cause of functional limitations in affected individuals. TKA reliably reduces pain but improvements in function are less predictable and deficits may persist for up to 2 years post-operatively. Patients undergoing elective surgery are routinely optimized medically but we hypothesized that pre-operative strength and fitness improvements would also enhance outcome.

Objectives: To determine the effect of a 6 week lower limb strengthening programme on post-operative QF strength and CSA, pain and functional scores.

To determine changes in Myosin Heavy Chain (MHC) isoform, hypertrophy marker IGF-1 and atrophy markers MuRF-1 and MAFbx.

Methods: 20 volunteers currently awaiting TKA were randomly assigned to a control [C] or intervention [I] group. [I] completed a 6 week home based, supervised exercise programme. Post-operatively all patients completed a standard inpatient physiotherapy routine.

Assessments were completed at baseline (T=0), T=6 weeks (just prior to operation) and 3 months post-operatively (T=18 weeks). Assessments included isokinetic dynamometry; MRI QF CSA and American Knee Society scores. A percutaneous muscle biopsy of the vastus lateralis muscle was also performed at T=0 and T=6 under local anaesthesia.

Results: At baseline there were no significant differences in parameters between groups. At T=18, [I] showed an 86% difference in QF peak torque above controls (P=0.003). CSA also improved by 6% versus a drop of 2.5% in [C] (P=0.041). Both groups showed improvements in Knee society function scores but [I] improved by 13 points more than [C] (P=0.044).

MHC IIa mRNA expression increased by 40% whilst IIx decreased by 60% representing a shift to a less fatigable fibre type (P=0.05 and 0.028 respectively). IGF-1, MuRF-1 and MAFbx mRNA levels did not change significantly in either group.

Conclusion: To our knowledge we have documented for the first time post-operative benefits by using a pre-operative training programme in TKA. This was manifest by continued rise in quadriceps peak torque, CSA and improved Knee society functional scores. We have also demonstrated the preservation of muscle plasticity in knee OA and suggest that factors other than known hypertrophy and atrophy pathways may be responsible.

Introduction: After total knee arthroplasty (TKA) patients develop marked asymmetrical quadriceps femoris (QFM) weakness due to neurological activation deficits and muscle atrophy; this is associated with a slow (type I) to fast (type II) shift in myosin heavy chain (MHC) expression. Preoperative resistance training (prehabilitation) has been shown to improve strength and function after TKA however is considered costly and labour intensive. Neuromuscular electrical stimulation (NMES) offers the potential for unsupervised training, although its role in prehabilitation has not been investigated.

Aims: Determine changes in myosin heavy chain (MHC) mRNA expression following preoperative NMES.

Evaluate the ability of NMES prehabilitation to improve strength and functional recovery post-TKA.

Methods: Randomised control efficacy study applying NMES to the affected QFM for 20 min, 5 days/week, for 8 weeks pre-TKA. Isometric QFM strength was determined dynametrically and muscle cross-sectional area (CSA) calculated from MRI axial images. Function was assessed with a walk test, stair-climb test, and chair-rise test. Real-time PCR analysed MHC mRNA expression. All evaluations were performed at baseline and preoperatively with strength, CSA and function also tested at 6 and 12 weeks post-TKA.

Results: Patients scheduled for TKA were recruited and randomised into control (n=9) or NMES (n=5) groups. Only the NMES group increased strength (27.8%; p=0.05) and CSA (7.4%; p=0.013) preoperatively. MHC type II mRNA decreased by 42% (p=0.078) indicating a fast to slow fibre shift. Function also improved in the NMES group (stair climb [p=0.006]; chair rise [p=0.018]). While all patients deteriorated after surgery, only the NMES group had notable strength gain from 6 to 12 weeks (53%; p=0.011) with associated functional recovery (stair-climb, p=0.017; chair-rise, p=0.01; walking speed, p=0.014). There were differences seen between the groups at 3 months post-TKA: stair climb (61.6%, p=0.04) and chair rise (28.4%, p=0.013). There was greater muscle atrophy seen in the controls than the NMES group post-TKA when compared to baseline (12.1% [p=0.034] versus 3.7% [ns]).

Conclusions: This study has shown that 8 weeks preoperative quadriceps strengthening using home-based NMES can safely and effectively attenuate the extent and duration of QFM weakness and atrophy after primary TKA. This translates into significantly faster functional recovery thereby expediting a return to normal activities.

Introduction: Quadriceps femoris muscle (QFM) weakness has been associated with the development and progression of knee osteoarthritis, primarily due to arthrogenic muscle inhibition. Neuromuscular electrical stimulation (NMES) devices cause muscle contraction by circumventing these neural inhibitory feedback pathways. While it has been proposed this occurs in a reversed pattern of muscle fibre recruitment, the molecular mechanisms have not been clearly elucidated.

Methods: This randomised control efficacy study applied NMES to the affected QFM for 20 min, 5 days a week, for 8 weeks. Strength was assessed dynometrically and function determined using validated measures (timed stair climb, chair rise and 25 metre walk tests). A quantitative polymerase chain reaction (PCR) method measured quantities of types I, IIa, and IIx myosin heavy chain (MHC) mRNA of muscle specimens taken from vastus lateralis of the affected QFM. Expression of genetic markers associated with muscle wasting (MAFbx and MURF-1; E3 muscle specific ligases of the ubiquitin proteasome pathway) and muscle anabolic states (IGF-1) were also determined. Statistical analysis was performed using ANOVA’s and independent t-test’s where appropriate.

Results: Sixteen patients (10 women and 6 men) with radiologically severe knee OA were recruited and randomised into a control (n=6) or intervention (n=10) group. Groups were similar in terms of age (64.8 ± 11.0 vs. 64.6 ± 7.6; mean ± SD) and BMI (31.8 ± 6.1 vs.30.7 ± 2.9). There were significant improvements in function (stair climb [p< 0.01]; chair rise [p< 0.01]) and QFM strength (isokinetic [p< 0.01]; isometric [p< 0.01]) in the NMES group at week 8 compared to week 0. At the genetic level, IGF1 expression significantly increased two-fold in the NMES group (p< 0.05); Despite a 17% decrease in MAFbx expression, neither it nor MURF-1 changed significantly. MHC-I and MHC-IIa mRNA expression did not change in either group; MHC-IIx decreased by 42% in the NMES group only but was not statistically significant.

Conclusions: The use of an 8 week NMES program produces significant quadriceps strength gain with associated functional improvements in subjects with severe knee OA. Expression of muscle atrophy markers did not change significantly; however increased IGF-1 expression could potentially inhibit further muscle atrophy. Of the 3 MHC mRNA isoforms, only MHC-IIx demonstrated a change in response to NMES. These results would indicate NMES induces early quadriceps strength gain by a predominantly neurological adaptation.

Introduction: Chronic stiffness is an uncommon complication of total knee arthroplasty (TKA) with reports in the literature citing an incidence of 1–5%. Surgical options to manage this debilitating condition include manipulation under anaesthesia (MUA) and arthrolysis; there is concern regarding revision surgery given the potential for stiffness recurrence.

Methods: Patients undergoing revision TKA for stiffness were prospectively identified. Inclusion criteria required a flexion contracture greater than 10 degrees and/or less than 70 degrees arc of motion. WOMAC and SF-36 self-report questionnaires were completed by all patients’ pre and post revision surgery.

Results: Between July 2005 and Dec 2006, 7 consecutive, aseptic, primary TKA’s were revised to address limited range of motion. Five female and 2 male patients (mean age: 57.6 years) underwent revision TKA 17.1 months (range, 7–25 months) after index TKA. All patients had attempted MUA, with additional open arthrolysis unsuccessful in 1 case. A medial parapatellar approach was performed although 3 required additional quadriceps snip for exposure. Five cases were revised with the Scorpio TS system and 2 with posterior stabilised components. Femoral augmentation was required in 2 cases and tibial in 1. Gap imbalance with increased soft tissue tension was noted intra-operatively in 5 cases with arthrofibrosis found in the remainder. At 6 months follow-up, arc of motion increased from a mean of 41.3° preoperatively to 81.4° (p=0.001) while mean flexion contracture decreased from 17.4° to 2.1° (p=0.004). Subjective improvement was also demonstrated: mean WOMAC decreased from 46.5 to 22.5 (p=0.023) and SF-36 scores increased by a mean of 35.8 points (p=0.001).

Conclusion: When conservative, implant preserving measures fail, revision surgery can be considered a viable option in addressing restricted movement following primary TKA. Aggressive physiotherapy and good patient compliance is required to minimise the recurrence of stiffness.

Background: Quadriceps femoris muscle (QFM) weakness has been implicated in the development of knee osteoarthritis (OA) as well as predicting functional ability after TKA. Preoperative strengthening (prehabilitation) may be facilitated by applying neuromuscular electrical stimulation (NMES) to the affected QFM using a garment-based portable stimulator.

Methods: Single blind, randomised control efficacy study with NMES applied to the affected QFM for 20 min, 5 days a week, for 8 weeks pre-TKA. Isokinetic and isometric strength was assessed at baseline, week 2, week 5 and immediately pre-op. Function was assessed using a 25 metre timed walk test (TWT), timed stair-climb test (SCT), and timed chair-rise test (CRT) at baseline and pre-op.

Results: 13 patients (8 women and 5 men) scheduled for TKA for knee OA were recruited and randomised into a control (n=5) or intervention (n=8) group. Groups were similar in terms of age (65.5 ± 6.8 vs. 61.8 ± 9.0; mean ± SD) and BMI (29.7 ± 2.1 vs.33.2 ± 5.6). There was an improvement in SCT (p< 0.01) and CRT (p< 0.01) in the NMES group at week 8 compared to week 0. Isokinetic hamstring strength and isometric QFM strength increased significantly at weeks 2, 5 and 8 compared to baseline whereas isokinetic QFM strength only increased at week 5 (p< 0.05) and week 8 (p< 0.01) compared to baseline.

Conclusion: The use of a portable home-based NMES program for 8 weeks results in significant strength gains with associated improvements in function in patients scheduled for TKA for knee OA.