Background. Acromegaly, which stems from high level of serum growth hormone secreted by a benign tumour in the anterior pituitary gland, is likely to cause severe peripheral joint pains due to hypertrophic changes in such joints. Recently, the life expectancy of such patients has been improved and more patients with acromegaly have undergone joint surgeries to mitigate joint pain and malfunctions. However, little is known about to what extent surgical procedures can improve the joint functions of acromegalic patients compared to non-acromegalic cases. Methods. First, we qualitatively analysed prognosis of total hip arthroplasty (THA) of acromegalic patients by investigating 11 cases in which direct anterior approach (DAA) THAs were performed to 8 acromegalic patients in our hospital between 2012 and 2015. Second, we quantitatively compared the functional prognosis of the 11 cases with that of 107 non-acromegalic cases. Technically, to control the difference in age, sex, height, and weight between the two patient groups, we first identified a model that could predict 3month-/6month-/12month-functional prognosis in the control cases. We estimated differences in functional outcomes between the two groups by calculating how accurately the control-case-based model could predict the prognosis of the acromegalic cases. Results. In the qualitative analysis, we found that compared to the control, the most acromegalic cases had atypically advanced degenerative arthritides with osteophytes and enthesophytes proliferations. In addition, some cases showed other signs, such as flattering of femoral head and arthritis with slight osteophytes. Regarding surgical procedures, acromegalic cases were likely to require longer operation time and larger amounts of blood loss compared to the control. In the quantitative analysis, we first identified a model in which age and body height could predict the functional prognosis of DAA THA in the non-acromegalic cases (F[2,104] = 6.7, P = 0.0017). We then found that the actual functional outcomes of the acromegalic cases were not significantly different from those predicted by this control-case-based model (P = 0.18). Conclusions. The qualitative analysis shows the atypical joint structures and resultant prolonged operation time and blood loss in the acromegalic cases. However, the quantitative analysis could not find significant differences in prognosis between the acromegalic and non-acromegalic cases. Although these observations and analyses need to be examined in studies with large sample sizes, this work suggests that functional outcomes of DAA THA to acromegalic patients can be comparable to that to non-acromegalic patients

Introduction. Problematic bone defects are encountered regularly in orthopaedic practice particularly in fracture non-union, revision hip and knee arthroplasty, following bone tumour excision and in spinal fusion surgery. At present the optimal source of graft to ‘fill’ these defects is autologous bone but this has significant drawbacks including harvest site morbidity and limited quantities. Bone marrow has been proposed as the main source of osteogenic stem cells for the tissue-engineered cell therapy approach to bone defect management. Such cells constitute a minute proportion of the total marrow cell population and their isolation and expansion is a time consuming and expensive strategy. In this study we investigated human bone marrow stem cells as a potential treatment of bone defect by looking at variability in patient osteogenic cell populations as a function of patient differences. We produced a model to predict which patients would be more suited to cell based therapies and propose possible methods for improving the quality of grafts. Methods. Bone marrow was harvested from 30 patients undergoing elective total hip replacement surgery in Musgrave Park Hospital, Belfast (12 males, 18 females, age range 52-82 years). The osteogenic stem cell fraction was cultured and subsequently analysed using colony forming efficiency assays, flow cytometry, fluorescence activated cell sorting and proteomics. Results. The number and proliferative capacity of osteogenic stem cells varied markedly between patients. Statistical analysis revealed significantly better osteogenic capacity in:. male patients. samples in which the growth hormone Fibroblastic Growth Factor-2 was added to culture medium. patients who used the cholesterol lowering agent simvastatin. Patient use of inhaled steroids and NSAIDs were found to have detrimental effects. A statistical model to predict marrow profiles based on these variables was produced. Conclusions. Stem cell based tissue engineering represents the future of the treatment of bone defect. This study provides evidence that inter-patient variability in marrow cell colony forming and proliferation ability can in some way be explained by patient associated factors. Using this knowledge, we can identify which patients would be best suited to this method of treatment and propose techniques for enhancement of their graft profiles