Hip arthroscopy is performed in a number of specialist centres throughout the UK with good results, no work has been published on the outcomes of hip arthroscopy in the District General Hospital setting. The early results from our prospective observational study show good outcomes in patients with femoro-acetabular impingement (FAI) and labral pathologies. To date we have follow-up data on 46 patients who have undergone hip arthroscopy with a mean follow-up period of 23 weeks. Of these patients 14 were male (30%) and 32 were female (70%) with a mean age of 36 years (16 to 62). Analysis of the data has shown a mean improvement in the Modified Harris Hip Score from 46.89 pre-operatively to 59.50 post-operatively (p<0.01) and a mean improvement in the Non-arthritic Hip Score from 47.38 pre-operatively to 66.74 post operatively (p<0.01). One of the patients has since undergone a total hip arthroplasty. There was one episode of minor wound infection treated successfully with oral antibiotics. There are been no cases of nerve injury or venous-thromboembolism. Our results demonstrate that hip arthroscopy can be provided safely in the DGH setting with good early functional outcomes.

Background

Acetabular or pelvic ring injuries are invariably associated with high-energy trauma that could lead to a significant degree of disability. The purpose of this study was to investigate whether patients who had surgical treatment of isolated acetabular or pelvic injuries were able to return to their previous sporting activities.

Introduction: The aim of this study was to develop a technique to decellularise a porcine cartilagebone construct with a view to using this as a biological scaffold for transplantation into human osteochondral defect as a cartilage substitute.

Methods: Decellularisation was based on a modification of the technique of Booth et al (2002). Cartilage bone matrix (n=9) were decellularised by exposing the tissue to 2 cycles of dry freeze-thaw followed 2 more cycles with the addition of hypotonic (10mM tris-HCl, pH8.0) buffer. Samples were then cycled through hypotonic buffer, followed by ionic detergent (0.1% [w/v] sodium dodecyl sulphate [SDS]) in the presence of protease inhibitors (aprotinin 10 KIU/ml) and 0.1% (w/v) ethylene diamine tetraacetic acid (EDTA). This was followed by washes in PBS with aprotinin and incubation in nuclease solution containing DNase (50U/ml) and RNase (1U/ml). Decontamination using 0.1% (v/v) peracetic acid in PBS was then incorporated to achieve disinfection of the tissue samples. Finally, samples were washed in PBS. Three decellularisation protocols were used depending on the number of hypotonic/SDS cycles: this was either done once, three or six times referred to as DC1, DC3 and DC6 respectively. Fresh & decellularised cartilage were compared histologically using haematoxylin and eosin staining, to visualize cellular content, sirius red, to visualise collagen fibres & alcian blue, to visualise glycosaminoglycans (GAG). Immunohistochemistry staining for galactose-α-1,3-galactose (α-gal), collagen I, II & VI was performed for fresh and decellularised samples. DNA assay: Genomic DNA was extracted using a DNA isolation kit for tissues (Roche Applied Sciences). Collagen and DMB sulphated sugar assay, as described by Stapleton et al. (2008), were performed to measure collagen and GAG content. The biphasic property of fresh and decellularised cartilage was determined using a pin on plate indentation test.

Results: H& E staining revealed the absence of visible whole cells. Sirius red stain gave evidence of the retention of collagen following decellularisation. In contrast, the acellular matrix showed evidence of loss of GAGs. There was no evidence of the expression of α-gal in the acellular scaffold. DNA analysis revealed the absence of genomic DNA in comparison to fresh tissues (ANOVA, p< 0.05). The decellularisation process had minimal effect on the collagen content of the cartilage. Nevertheless there was a significant difference in the sulphated sugar content of the fresh tissue when compared to the decellularised tissue (ANOVA, p< 0.05), indicating loss of 92% GAG. Biomechanical testing of decellularised tissues showed a significant change (ANOVA, p< 0.05) in comparison to the fresh cartilage.

Discussion: In conclusion this study has generated data on the production of an acellular cartilage bone matrix scaffold for use in osteochondral defect repair. To our knowledge, this is the first study that has successfully removed whole cells and α-gal from xenogeneic cartilage and bone tissue. Future studies are required to investigate methods to recellularise the acellular matrix using an appropriate cell type and mechanical conditioning and to investigate replenishing GAG loss following decellularisation.

Background: Acetabular or pelvic ring injuries are invariably associated with high-energy trauma that could lead to a significant degree of disability. The purpose of this study was to investigate whether patients who had surgical treatment of isolated acetabular or pelvic injuries were able to return to their previous sporting activities.

Patients and Methods: Between Jan 2001 to Jan 2002, 68 consecutive patients were treated in our institution with isolated pelvic (PF) or acetabular fractures (AF). Demographics, fracture classification, rehabilitation, outcome and complications were documented prospectively. Frequency, level of activity and sports participation before and after surgery, as well as EuroQol (EQ-5D) was also recorded.

Results: There were 58 male and 10 female patients, with a mean age of 42 years (16–80) and mean follow-up 30 months (24–36). 43 out of 53 (81%) patients in AF group and 13 out 15 patients in PF group (83%) returned to a variable level of sports activity. Significant reduction in the level of activity was observed in those who sustained both column (BC) (p< 0.04) and posterior wall (PW) (p< 0.0009) fractures in the AF group. Significant reduction in frequency of sports practice also found in PW subgroup (p< 0.0001). Patients < 25 and > 40 years of age in PF group and < 40 or > 65 in AF group had significant reduction in EQ-5D scores in comparison to normal UK population.

Conclusion: The majority of patients returned back to sports activities following surgery. The worst prognosis lies with BC and PW acetabular fractures. Middle age patients do better comparing to younger or elderly patients in both groups.