Does the osteonecrotic volume/other factors predict progression to total knee arthroplasty in spontaneous osteonecrosis of the knee? An MRI study.

Background: The aim of this study is to determine whether the volume of the osteonecrotic lesion in spontaneous osteonecrosis of the knee (SONK) or other prognostic factors predict progression to total knee arthroplasty (TKA). The secondary aim is to analyse co-relation of volume of osteonecrotic lesion versus other prognostic factors The authors hypothesize that a greater osteonecrotic volume predicts progression to TKA. Materials and methods: A retrospective study was conducted at a single tertiary hospital. All patients under the care of a single surgeon with magnetic resonance imaging (MRI)-proven SONK were included from the period of January 2011 to January 2018. Survival analysis was conducted to evaluate for progression to TKA based on volume and location of osteonecrotic lesion. Univariate and multivariate analyses were performed to identify potential risk factors for TKA. Results: 42 patients with MRI-proven SONK were evaluated. 9 patients (21.4 %) required TKA. There was no significant association between progression to TKA with volume of the osteonecrotic lesion. Other factors such as age, gender, body mass index, degree of bony edema and cartilage damage, presence of meniscal tear and subchondral fractures and location of osteonecrotic lesion were also not significant. Conclusion: The volume of the osteonecrotic lesion and other evaluated prognostic factors were not predictive of the progression to TKA for patients with SONK.

Polka dot cementless talar component in enhancing total ankle replacement fixation: A parametric study using the finite element analysis approach.

The primary stability of a total ankle replacement (TAR) is essential in preventing long-term aseptic loosening failure and could be quantified based on micromotion at the bone-prosthesis interface subjected to physiological loading during the normal walking. A 3D finite element analysis was conducted to investigate the current commercial STAR™ Ankle TAR bone-prosthesis interface relative micromotion (BPIRM) with addition of the talus bone minimum principal bone stresses (MPBS). Comparison was made to the proposed polka dot designs with the hemispheric feature that was demonstrated to enhance BPIRM. Parametric studies were conducted on the hemispheric features with changes in its diameter, length and shape. The FE results indicated high BPIRM at the talar component was primarily contributed by de-bonding (in the normal direction) between the talus bone and talar component. The MPBS were found to be most significant in the superior anterior and superior medial regions of the talus bone. When the pin length was increased from 1.5 to 3 mm, the BPIRM was predicted to fall below 50 µm in favour of bone in-growth. Based on the practicality of the prosthesis implantation during the surgical procedure, the final design that incorporated both the initial polka dot and 3 mm pin length in a crisscross manner was deemed to be a favorable design with reduced BPIRM and MPBS hence lowering the risk of long-term aseptic loosening.

Management of aseptic failure of the mobile-bearing Oxford unicompartmental knee arthroplasty.

BACKGROUND: Unicompartmental knee arthroplasty (UKA) accounts for 9.1% of primary knee arthroplasties (KAs) in the UK. However, wider uptake is limited by higher revision rates compared with total knee arthroplasties (TKA) and concerns over subsequent poor function. The aim of this study was to understand the revision strategies and clinical outcomes for aseptic, failed UKAs at a high-volume centre. METHODS: This was a retrospective, single-centre cohort study of 48 patients (31 female, 17 male) with 52 revision UKAs from 2006 to 2018. Median time to revision was 67 (range 4-180) months. Indications for revision were progression of osteoarthritis (n = 31 knees, 59.6%), unexplained pain (n = 10 knees, 19.2%), aseptic loosening (n = 6 knees, 11.5%), medial collateral ligament incompetence (n = 3 knees, 5.8%) and recurrent bearing dislocation (n = 2 knees, 3.8%). Technical details of surgery, complications and functional outcome were recorded. RESULTS: Failed UKAs were revised to primary TKAs (n = 29 knees, 55.8%), revision TKAs (n = 9 knees, 17.3%), bicompartmental KAs (n = 11 knees, 21.2%), or unicompartmental-to-unicompartmental KAs (n = 3 knees, 5.8%). Median follow up was 81 (range 24-164) months. Four patients (7.7%) died from unrelated causes. No re-revisions were identified. Surgical complications required re-operation in five knees (9.6%). Median Oxford Knee Score at latest follow up was 38 (range 9-48) points and median EQ5D3L index 0.707 (range -0.247 to 1.000). CONCLUSIONS: Aseptic, revision UKA at a high-volume centre had good clinical outcomes. Bicompartmental KA demonstrated excellent function and should be considered an alternative to TKA for progression of osteoarthritis for appropriately trained surgeons.

CHI study: protocol for an observational cohort study on ageing and mental health in community-dwelling older adults.

INTRODUCTION: Ageing is associated with a multitude of healthcare issues including dementia, depression, frailty, morbidity associated with chronic disease and high healthcare utilisation. With Singapore's population projected to age significantly over the next two decades, it has become increasingly important to understand the disease burden and etiological process among older adults. The Community Health and Intergenerational study aims to holistically examine ageing in place by investigating the resilience and vulnerability factors of the ageing process in the biological, psychological and social domains within the environment. METHODS AND ANALYSIS: Using a cohort multiple randomised controlled trial design, comprehensive health profiles of community-dwelling older adults will be collected. The objective is to recruit 1000 participants (aged 60-99 years) living in the western region of Singapore within a period of 3 years (2018-2020). Assessments include basic sociodemographic, physical health and function (cardiac, oral and blood profiles and visual function), cognitive functioning, daily functioning, physical fitness, emotional state, free-flowing speech, sleep quality, social connectedness, caregiver burden, intergenerational communication, quality of life, life satisfaction, attitudes to ageing and gratitude and compassion. Results from the cohort will enable future studies to identify at-risk groups and develop interventions to improve the physical and mental health and quality of life of older adults. ETHICS AND DISSEMINATION: Approval of the cohort study by the National University of Singapore Institutional Review Board (NUS-IRB Reference code: H-17-047) was obtained on 12 October 2017. Written consent will be obtained from all participants. Findings from the cohort study will be disseminated by publication of peer-reviewed manuscripts, presentations at scientific meetings and conferences with local stakeholders.

Finite element analysis of bone-prosthesis interface micromotion for cementless talar component fixation through critical loading conditions.

The total ankle replacement (TAR) survivability rate is still suboptimal, and this leads to many orthopaedic surgeons opting arthrodesis as a better option for the ankle arthritis patients. One of the fundamental reasons is due to the lack of primary stability of the prosthesis fixation at the bone-prosthesis interface hence leading to long-term aseptic loosening of the talar component. The commercially available Scandinavian Total Ankle Replacement (STAR) Ankle design and several additional design features (including trabecular metal, side fin, double fin, and polka-dot designs) were studied using finite element analysis, and the bone-prosthesis interface relative micromotion (BPIRM) and talar bone minimum principal stresses were examined and analysed. Three loading conditions at a gait cycle of heel strike, midstance, and toe off with different meniscal bearing displacement were also included as part of the study parameters. The results were correlated to in vitro cadaveric measurements and reported clinical studies. Simulated results showed that the de-bonding relative distance between the bone and prosthesis upon loading (COPEN defined by the simulation software) was the main reason constituting to the high interface micromotion between the talar component and talus bone (which could lead to long-term aseptic loosening). The polka-dot design was shown to induce the lowest BPIRM among all the designs studied.

Fate of the Retained Acetabular Component During Revision Total Hip Arthroplasty: A Meta-Analysis and Systematic Review.

BACKGROUND: The aim of this meta-analysis and systematic review is to estimate re-revision rates due to aseptic loosening of retained acetabular components after revision total hip arthroplasty. METHODS: PubMed, EMBASE, Cochrane Library, and Web of Science were searched until June 11, 2018. Data were extracted by 2 independent investigators and consensus was reached with the involvement of a third investigator. Rates of re-revision due to aseptic loosening from 6 studies were aggregated using random effects model after a logit transformation and were grouped by study and population level characteristics. RESULTS: An assessment of the re-revision rates of retained acetabular components due to aseptic loosening in revision total hip arthroplasty was reported in 6 studies involving 669 cases. The pooled re-revision rate was 12.6% (95% confidence interval 8.4-18.4) with a mean study follow-up of 8.6 years. The rate of re-revision due to aseptic loosening of retained acetabular components was 6.8% (95% confidence interval 3.4-13.3). In the univariate meta-regression analysis, mean age at index revision surgery was significantly associated with the rate of re-revision due to aseptic loosening (R2 = 99.98%, P < .0001). CONCLUSION: Based on this exploratory analysis, revision hip procedures with retentions of well-fixed acetabular components generally have a low risk of failure during mid-term to long-term follow-ups.

Biomechanical analysis of proximal tibia bone grafting and the effect of the size of osteotomy using a validated finite element model.

Harvesting bone graft from the proximal tibia is gaining popularity, with lower complication rates and adequate quantity of cancellous bone. The amount of harvested bone is dependent on the size of the cortical window introduced via osteotomy onto the proximal tibia, and its mechanical strength after surgery could be compromised. The aim of the study was to investigate the proximal tibia's mechanical stability after bone harvesting and the effect of varying window sizes using a validated finite element model. Two cadaveric tibiae were tested with bone strains measured for different circular cortical window diameters (10-25 mm). Sixteen finite element models of the intact and harvested tibia were simulated and validated with experimental data. The experimental and predicted max/min principal bone strains were fitted into regression models and showed good correlations. It was predicted the maximum principal bone stresses were greatest and concentrated at postero-inferior and antero-superior regions of the cortical window. A stress line progressed from the edge of the window to the posterior side of the tibia, which became more prominent with the increase of size of the cortical window. It was found that large circular osteotomies for bone harvesting at the proximal tibia induced stress concentrations and stress lines which could lead to eventual failure. Graphical abstract The formation of a stress line in the harvested tibia initiated from the postero-inferior edge of the window and progressed to the medial side. The stress line became more prominent with the increase of the size of the cortical window from 10 to 25 mm in diameter.

Clinical outcomes of the reverse McLaughlin procedure for Hill-Sachs lesions in anterior shoulder instability.

INTRODUCTION: Engaging Hill-Sachs lesions in recurrent anterior shoulder dislocation have been managed with the remplissage procedure. Clinical and cadaveric studies have reported limitation of rotation after this procedure. We introduce the reverse McLaughlin procedure where the infraspinatus and the underlying capsule are detached and approximated into the Hill-Sachs defect with transosseous sutures. This is a preliminary report using this technique. METHODS: Seventeen patients with recurrent anterior shoulder dislocations and an engaging Hill-Sachs lesion underwent a Bankart repair and remplissage procedure (n = 9) or the reverse McLaughlin procedure ( n = 8). Patients were evaluated using the SF-36, American Shoulder and Elbow Surgeons (ASES), and Constant scores. Clinical assessment of the shoulders was also performed. RESULTS: At the final follow-up, all patients in both groups achieved comparable clinical outcome scores. No significant differences were reported in the range of motion of the shoulders between the two groups. There was one dislocation of the operated shoulder in each group after an injury. CONCLUSION: The reverse McLaughlin procedure for engaging Hill-Sachs lesions is simple, easy to perform, and associated with functional outcomes and range of motion at least equivalent to those obtained via the remplissage technique. It may be an alternative to the latter procedure. LEVEL OF EVIDENCE: III, Retrospective Comparative Study.

Smoking is associated with earlier time to revision of total knee arthroplasty.

BACKGROUND: Smoking is associated with early postoperative complications, increased length of hospital stay, and an increased risk of revision after total knee arthroplasty (TKA). However, the effect of smoking on time to revision TKA is unknown. METHODS: A total of 619 primary TKAs referred to an academic tertiary center for revision TKA were retrospectively stratified according to the patient smoking status. Smoking status was then analyzed for associations with time to revision TKA using a Chi square test. The association was also analyzed according to the indication for revision TKA. RESULTS: Smokers (37/41, 90%) have an increased risk of earlier revision for any reason compared to non-smokers (274/357, 77%, p=0.031). Smokers (37/41, 90%) have an increased risk of earlier revision for any reason compared to ex-smokers (168/221, 76%, p=0.028). Subgroup analysis did not reveal a difference in indication for revision TKA (p>0.05). CONCLUSIONS: Smokers are at increased risk of earlier revision TKA when compared to non-smokers and ex-smokers. The risk for ex-smokers was similar to that of non-smokers. Smoking appears to have an all-or-none effect on earlier revision TKA as patients who smoked more did not have higher risk of early revision TKA. These results highlight the need for clinicians to urge patients not to begin smoking and encourage smokers to quit smoking prior to primary TKA.

Weight Gain After Primary Total Knee Arthroplasty Is Associated With Accelerated Time to Revision for Aseptic Loosening.

BACKGROUND: Obesity is a major health problem worldwide and is associated with complications after total knee arthroplasty (TKA). It remains unknown whether a change in body mass index (BMI) after primary TKA affects the reasons for revision TKA or the time to revision TKA. METHODS: A total of 160 primary TKAs referred to an academic tertiary center for revision TKA were retrospectively stratified according to change in BMI from the time of their primary TKA to revision TKA. The association between change in BMI and time to revision was also analyzed according to indication for revision of TKA using Pearson's chi-square test. RESULTS: The mean change in BMI from primary to revision TKA was 0.82 ± 3.5 kg/m2. Maintaining a stable weight after primary TKA was protective against late revision TKA for any reason (P = .004). Patients who failed to reduce their BMI were revised for aseptic loosening earlier, at less than 5 years (P = .020), whereas those who reduced their BMI were revised later, at over 10 years (P = .004). CONCLUSION: Maintaining weight after primary TKA is protective against later revision TKA for any reason but failure to reduce weight after primary TKA is a risk factor for early revision TKA for aseptic loosening and osteolysis. Orthopedic surgeons should recommend against weight gain after primary TKA to reduce the risk of an earlier revision TKA in the event that a revision TKA is indicated.

Cortical Strut Allograft Support of Modular Femoral Junctions During Revision Total Hip Arthroplasty.

BACKGROUND: There is risk of junction failure when using modular femoral stems for revision total hip arthroplasty (THA), especially with loss of bone stock in the proximal femur. Using a cortical strut allograft may provide additional support of a modular femoral construct in revision THA. METHODS: We reviewed prospectively gathered clinical and radiographic data for 28 revision THAs performed from 2004 to 2014 using cementless modular femoral components with cortical strut allograft applied to supplement proximal femoral bone loss: 5 (18%) were fluted taper designs and 23 (82%) were porous cylindrical designs All the patients had a Paprosky grade IIIA or greater femoral defect. The mean follow-up was 5.4 ± 3.9 years. RESULTS: The Harris Hip Scores improved from 26 ± 10 points preoperatively to 71 ± 10 points at final follow-up (P < .001). The Western Ontario McMaster Universities Osteoarthritis Index scores improved from 45 ± 12 points preoperatively to 76 ± 12 points at final follow-up (P < .001). Eighty-nine percent (25 hips) of all revision or conversion THAs were in place at final follow-up. Three (11%) patients underwent reoperations, 2 for infection and 1 for periprosthetic fracture. There was no statistical significant change in femoral component alignment (P = .161) at final follow-up. Mean subsidence was 1.8 ± 1.3 mm at final follow-up. Femoral diameter increased from initial postoperative imaging to final follow-up imaging by a mean of 9.1 ± 5.1 mm (P < .001) and cortical width increased by a mean of 4.5 ± 2.2 mm (P < .001). Twenty-seven hips (96%) achieved union between the cortical strut allograft and the host femur. CONCLUSION: The use of a modular femoral stem in a compromised femur with a supplementary cortical strut allgraft is safe and provides satisfactory clinical and radiological outcomes.

Use of Cortical Strut Allograft After Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty.

BACKGROUND: Cortical strut allografts restore bone stock and improve postoperative clinical scores after revision total hip arthroplasty (THA). However, use of a cortical strut allograft is implicated in delayed healing of an extended trochanteric osteotomy (ETO). To date, there are no reports directly comparing ETO with or without cortical strut allografts. METHODS: We reviewed prospectively gathered data on 50 revision THAs performed from 2004-2014 using an ETO. We compared the demographic, radiological, and clinical outcome of patients with (16 hips) and without (34 hips) cortical strut allograft after an ETO. RESULTS: There were no significant differences in Western Ontario McMaster Universities Osteoarthritis Index or Harris Hip Score between the ETOs with and without a cortical strut allograft. Fifteen of the ETOs (94%) with a cortical strut allograft and 31 of the ETOs (91%) without a cortical strut allograft were in situ at final follow-up (P = 1.000). A higher proportion hips with cortical strut allograft (100%, 16 patients) had preoperative Paprosky grade bone loss more than IIIA compared to those without allograft (29%, 10 patients) (P < .001). There were no differences in femoral stem subsidence (P = .207), alignment (P = .934), or migration of the osteotomized fragment (P = .171). Fourteen of the ETOs (88%) in patients with cortical strut allograft united compared to 34 ETOs (100%) in patients without allograft (P = .095). CONCLUSION: Our study shows that the use of cortical strut allograft during revision THA with ETO does not reduce the rate of union, radiological or clinical outcomes.

A double button adjustable loop device is biomechanically equivalent to tension band wire in the fixation of transverse patellar fractures-A cadaveric study.

INTRODUCTION: Tension-band wire fixation of patellar fractures is associated with significant hardware-related complications and infection. Braided polyester suture fixation is an alternative option. However, these suture fixations have higher failure rates due to the difficulty in achieving rigid suture knot fixation. The Arthrex syndesmotic TightRope, which is a double-button adjustable loop fixation device utilizing a 4-point locking system using FibreWire, may not only offer stiff rigid fixation using a knotless system, but may also obviate the need for implant removal due to hardware related problems. The aim of our study is to compare the fixation rigidity of patella fractures using Tightrope versus conventional tension-band wiring (TBW) in a cadaveric model. MATERIALS AND METHODS: TBW fixation was compared to TightRope fixation of transverse patella fractures in 5 matched pairs of cadaveric knees. The knees were cyclically brought through 0-90° of motion for a total of 500 cycles. Fracture gapping was measured before the start of the cycling, and at 50, 100, 200 and 500 cycles using an extensometer. The mean maximum fracture gapping was derived. Failure of the construct was defined as a displacement of more than 3mm, patella fracture or implant breakage. RESULTS: All but one knee from each group survived 500 cycles. The two failures were due to a fracture gap of more than 3mm during cycling. There was no significant difference in the mean number of cycles tolerated. There was no implant breakage. There was no statistical significant difference in mean maximum fracture gap between the TBW and TightRope group at all cyclical milestones after 500 cycles (0.3026±0.4091mm vs 0.3558±0.7173mm, p=0.388). CONCLUSIONS: We found no difference between the TBW and Tightrope fixation in terms of fracture gapping and failure. With possible lower risk of complications such as implant migration and soft tissue irritation, we believe tightrope fixation is a feasible alternative in fracture management of transverse patella fractures.

Revision Hip Arthroplasty Using a Modular, Cementless Femoral Stem: Intermediate-Term Follow-Up.

BACKGROUND: Modular femoral stem provides flexibility in femoral reconstruction, ensuring improved "fit and fill". However, there are risks of junction failure and corrosion, as well as cost concerns in the use of modular femoral stems. METHODS: We reviewed prospectively-gathered clinical and radiographic data on revision total hip arthroplasties (THAs) performed from 2001-2007 using modular, cementless femoral component performed by the 2 senior authors. Patients with a minimum follow-up of 7 years were included in this study. RESULTS: Sixty-four patients (68 hips) with a median age of 68 ± 14 years (range 40-92 years) at revision THA were included. The median follow-up was 11.0 ± 1.8 years (range 7-14). Harris hip score, femoral stem subsidence, and stem osseointegration were recorded. The Harris hip score improved from an average of 38.1-80.1 (P < .01). Five hips had one or more dislocations. Seven patients underwent reoperations, 3 of which did not involve the stem. Four stems required revision because of infection, recurrent dislocation, or suboptimal implant position. Survival rates for any reasons and revision for femoral stems were 90% and 94%, respectively, at the most recent follow-up. Four stems subsided more than 5 mm, but established stable osseointegration thereafter. Seven nonloose stems (10.2%) demonstrated radiolucent lines in Gruen zones 1 and 7. No complications regarding the modular junction were encountered. CONCLUSION: Modular, cementless, extensively porous-coated femoral components have demonstrated intermediate-term clinical and radiographic success. Initial distal intramedullary fixation ensures stability, and proximal modularity further maximizes fit and fill.

A biomechanical study of proximal tibia bone grafting through the lateral approach.

BACKGROUND: Autologous bone graft remains the gold standard source of bone graft. Iliac crest has traditionally been the most popular source for autologous bone graft. However, iliac crest bone graft harvesting is associated with high donor site morbidity. Bone graft harvesting from the proximal tibia has shown great potential with reported low complication rates. However, there is a paucity of biomechanical studies concerning the safety as well as yield of proximal bone graft harvesting. PURPOSE: This biomechanical study was designed to investigate (1) the stability of the harvested proximal tibial during physiological loading, and (2) the maximum size of the cortical window that can be safely created and (3) volume of accessible bone graft. METHODS: Bone grafts were harvested from eleven cadaveric tibiae using a circular cortical window along the lateral proximal tibia. These harvested proximal tibiae were then loaded under physiological conditions (mean 2320N, range 1650-3120N) using a customized test fixture. Strain rosettes were mounted at 7 locations in the harvested proximal tibia to record the changes in strain at the harvested proximal tibia. The change in strain with increasing cortical window size (10-25mm diameter) was also studied. Bone principal strains as well as volume of bone harvested were recorded. RESULTS: A repeated measures ANOVA was used to analyze the change in bone strains with the cortical window size. Statistically significant (p<0.05) increases in bone strains at the anterior and medial aspects of the tibia were observed with increasing size of osteotomies (-328.85µÎµ, SD=232.21 to -964.78µÎµ, SD=535.89 and 361.64µÎµ, SD=229.90 to -486.08µÎµ, SD=270.40 respectively), and marginally significant changes in strain at the lateral and posterior aspects. None of the tibiae failed under normal walking loads even with increasing osteotomies size of 10-25 mm diameter. A smaller osteotomy of 10mm diameter yielded an average volume of 7.15ml of compressed bone graft, while a larger osteotomy of 25mm diameter yielded on average an additional 3.64ml of bone graft. Bone grafting of the proximal tibia through the lateral approach with a circular osteotomy is a feasible option even with osteotomies of 25mm diameter. Even though increased bone strains were observed, the strains did not exceed the yield strain of cortical bone when loaded under normal walking conditions. The quantity of bone harvested from the proximal tibia is comparable to that harvested from the iliac crest. CONCLUSIONS: This biomechanical study demonstrated the stability of the harvested proximal tibia under conditions of full weight bearing ambulation. It has also refined the technique of proximal bone graft harvesting by determining the maximum size of the cortical window. The findings of this study add to the overall understanding of proximal tibial bone graft harvesting, providing objective data regarding stability as well as yield. This information would be useful during selection of source of autologous bone graft.

A useful surgical technique for retrieval of a broken guide pin in the midfoot.

Perioperative instrument breakage is not an infrequent occurrence, even for experienced surgeons. The most commonly reported instrument breaks in orthopedic procedures are drill bits, followed by Kirschner wires and cannulated guide pins. The reasons for failure include improper technique and repetitive use. The retrieval of broken hardware can be technically challenging, particularly if the fragment has become embedded in bone. Retrieval methods have been described for cannulated guide pin fragments in the hip; however, no specific techniques have been described for the retrieval of guide pin fragments embedded in the bones of the foot. In the present report, we describe a technique we have found useful for retrieval of a guide pin fragment that had broken off during a Lisfranc fracture repair 6 weeks earlier. The technique was used in a delayed situation; however, we believe it would be even easier to use during an intraoperative breakage.

The relationship between body mass index and physical activity levels in relation to bone mineral density in premenopausal and postmenopausal women.

UNLABELLED: We prospectively analyzed 283 women to evaluate the effects of body mass index (BMI) and physical activity levels on bone mineral density (BMD) progression in pre- and postmenopausal women over 2 years. In postmenopausal women, lower BMI was linked with worsening BMD, and moderate activity levels were associated with a lower likelihood of worsening BMD at 2 years. PURPOSE: The aim of our study is to evaluate the effects of BMI and physical activity levels on BMD progression in pre- and postmenopausal Asian women over 2 years. METHODS: We prospectively analyzed 283 women from 2006 to 2009. They were divided into two groups (159 pre- and 124 postmenopausal) and analyzed separately to avoid confounding by age and menopausal hormonal status. The mean follow-up period was 771 days. Demographic data was obtained, including medical history, calcium supplementation, BMI, and physical activity levels (IPAQ scale). Bilateral femoral neck BMD was determined at the time of recruitment, 1 year, and after 2 years. Generalized linear modeling was used to evaluate the effects of BMI and physical activity levels on BMD progression over a 2-year period. RESULTS: Amongst premenopausal women, lower initial femoral neck BMD scores were linked to worsening BMD (p = 0.048). In postmenopausal women, lower BMI was linked with worsening BMD (p = 0.012). Postmenopausal patients with moderate activity levels had a lower likelihood of worsening BMD at 2 years (p = 0.038). High physical activity levels were linked to a lower risk of BMD worsening (p = 0.066). CONCLUSIONS: Higher BMI scores are protective for osteoporosis in postmenopausal women. Moderate levels of physical activity are beneficial for bone health in postmenopausal women, while low physical activity levels are not helpful. We recommend that, in the secondary prevention of osteoporosis, postmenopausal women should be encouraged to participate regularly in moderate physical activities. A practical approach would be walking 30 min a day for at least 5 days per week.

Clinical outcomes of below knee amputations in diabetic foot patients.

INTRODUCTION: This study aims to evaluate the predictive factors affecting the clinical outcome of Below Knee Amputations (BKA) performed in diabetic foot patients admitted to National University Hospital (NUH) Multi-Disciplinary Diabetic Foot Team. MATERIALS AND METHODS: This is a prospective cohort study of 151 patients admitted to the Department of Orthopaedic Surgery, NUH, for Diabetic Foot Problems (DFP) from January 2006 to January 2010. All had undergone BKA performed by NUH Multi-Disciplinary Diabetic Foot Team. Statistical analyses (univariate and multivariate analysis with logistic regression) were carried out using SPSS version 18.0, for factors such as demographic data, diabetic duration and control, clinical findings and investigations, indications for surgery, preoperative investigations and evaluation, microbiological cultures, and these were compared to the clinical outcome of the patient. A good clinical outcome is defined as one not requiring proximal re-amputation and whose stump healed well within 6 months. The ability to ambulate with successful use of a prosthesis after 1 year was documented. Statistical significance was set at P <0.050. RESULTS: Mean age of study population was 55.2 years with a male to female ratio of about 3:2. Mean follow up duration was 36 months. Of BKAs, 73.5% gave a good outcome. Univariate analysis showed that smoking, previous limb surgery secondary to diabetes, high Total White Count (TW), Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP), Urea, Creatinine (Cr), Neutrophils, absence of posterior tibial and popliteal pulses, low Ankle Brachial Index (ABI) and Toe Brachial Index (TBI) were associated with poor clinical outcome. Multivariate analysis showed that high CRP, ESR, Neutrophils, absence of popliteal pulse and low ABI were associated with poor clinical outcome. Of patients, 50.3% attained mobility with prosthesis after 1 year. Mortality rate was 21.2% within 6 months of operation, with sepsis being the most significant cause of death. CONCLUSION: Success rate of BKA was 73.5%, with mortality rate being 21.2% within 6 months. In this cohort, 50.3% were able to attain eventual mobility with prosthesis after 1 year. Sepsis was the most significant cause of death. Markers of infection such as high CRP, ESR, neutrophils; and indicators of poor vascularity such as absence of popliteal pulse and low ABI were significantly associated with poor clinical outcome.

Evaluation of the role and cost-effectiveness of end-of-life orthopaedic interventions in cancer patients with skeletal metastases to the hip.

This study aimed to evaluate the effect of hip reconstruction on patients with skeletal metastases to the hip. We investigated the effect of hip reconstruction on quality of life and ambulatory status, as well as cost-effectiveness of hip reconstruction in this group of patients.