Polymethyl methacrylate spacers are commonly used during staged revision knee arthroplasty for infection. In cases with extensive bone loss and ligament instability, such spacers may not preserve limb length, joint stability and motion.

We report a retrospective case series of 19 consecutive patients using a custom-made cobalt chrome hinged spacer with antibiotic-loaded cement. The “SMILES spacer” was used at first-stage revision knee arthroplasty for chronic infection associated with a significant bone loss due to failed revision total knee replacement in 11 patients (58%), tumour endoprosthesis in four patients (21%), primary knee replacement in two patients (11%) and infected metalwork following fracture or osteotomy in a further two patients (11%). Mean follow-up was 38 months (range 24–70). In 12 (63%) patients, infection was eradicated, three patients (16%) had persistent infection and four (21%) developed further infection after initially successful second-stage surgery. Above knee amputation for persistent infection was performed in two patients.

In this particularly difficult to treat population, the SMILES spacer two-stage technique has demonstrated encouraging results and presents an attractive alternative to arthrodesis or amputation.

Matrix-induced autologous chondrocyte implantation (MACI) is an established technique used to treat osteochondral lesions in the knee. For larger osteochondral lesions (> 5 cm²) deeper than approximately 8 mm we have combined the use of two MACI membranes with impaction grafting of the subchondral bone. We report our results of 14 patients who underwent the ‘bilayer collagen membrane’ technique (BCMT) with a mean follow-up of 5.2 years (2 to 8). There were 12 men and two women with a mean age of 23.6 years (16 to 40). The mean size of the defect was 7.2 cm² (5.2 to 12 cm²) and were located on the medial (ten) or lateral (four) femoral condyles. The mean modified Cincinnati knee score improved from 45.1 (22 to 70) pre-operatively to 82.8 (34 to 98) at the most recent review (p < 0.05). The visual analogue pain score improved from 7.3 (4 to 10) to 1.7 (0 to 6) (p < 0.05). Twelve patients were considered to have a good or excellent clinical outcome. One graft failed at six years.

The BCMT resulted in excellent functional results and durable repair of large and deep osteochondral lesions without a high incidence of graft-related complications.

The results for autologous chondrocyte implantation (ACI) in the treatment of osteochondral defects in the knee are encouraging. At present, two techniques have been described to retain the chondrocyte suspension within the defect. The first involves using a periosteal flap harvested from the distal femur and the second involves using a type I/III collagen membrane. To the authors' knowledge there are no comparative studies of these two techniques in the current literature.

A total of 68 patients with a mean age of 30.52 years (range 15 to 52 years) with symptomatic articular cartilage defects were randomised to have either ACI with a periosteal cover (33 patients) or ACI with a type I/III collagen cover (35 patients). The mean defect size was 4.54 cm² (range 1 to 12 cm²). All patients were followed up at 24 months.

A functional assessment using the Modified Cincinnati score showed that 74% of patients had a good or excellent result following the ACI with collagen cover compared with 67% after the ACI with periosteum cover at 2 years (p>0.05). Arthroscopy at 1 year also demonstrated similar results for both techniques. However, 36.4% of the periosteum covered grafts required shaving for hypertrophy compared with 1 patient for the collagen covered technique.

This prospective, randomised study has shown no statistical difference between the clinical outcome of ACI with a periosteal cover versus ACI with a collagen cover at 2 years. A significant number of patients who had the ACI with periosteum technique required shaving of a hypertrophied graft within the first year of surgery. We conclude that there is no advantage in using periosteum as a cover for retaining the chondrocytes within an osteochondral defect; as a result we advocate the use of an alternative cover such as a porcine-derived, type I/III collagen membrane.

Introduction: Massive endoprostheses are widely employed in limb salvage surgery for malignant bone tumours. Whilst joint preservation rather than replacement is usually attempted, cases arise where there is insufficient bone following tumour resection to allow adequate fixation of a joint sparing prosthesis.

Method: We report a series of four patients (aged 4–12), in which irradiated autologous bone was combined with distal femoral replacement in order to preserve the native hip joint.

Results: There were three cases of Osteosarcoma and one Ewing’s sarcoma. After a mean follow-up of 53.5 months (range 9–168), all four patients are alive without evidence of local recurrence or metastases. One implant was revised after 14 years following fracture of the extending component of the growing endoprosthesis. There were no cases of loosening or peri-prosthetic fracture.

Discussion: This is the first report of a new technique utilising irradiated autologous proximal femoral bone combined with distal femoral replacement in skeletally immature patients.

For any fracture classification, a high level of intraobserver reproducibility and interobserver reliability is desirable. We compare the consistency of the AO and Neer classifications for proximal humerus fractures with an assessment of the digitised radiographs of 100 fractures by 10 orthopaedic surgeons and 5 radiologists using the General Electric Picture Archiving and Communications System (PACS), allowing manipulation of the image. This process repeated 1 month later.

Reproducibility and reliability moderate for both the AO and Neer systems. Reproducibility using the AO/ ASIF system was slightly greater. The assessor’s level of experience and specialty did affect accuracy. The ability to electronically manipulate images does not improve reliability and their sole use in describing these injuries and comparing similarly classified fractures from different centres is not recommended.

Fractures of the proximal humerus are common. Most undisplaced or minimally displaced, and treated conservatively. Up to one fifth may benefit from surgery. As decisions regarding treatment are based on the fracture type, a radiological classification should be easy to use and have a high degree of reliability and reproducibility to serve as a useful discriminator, creating standards by which treatment can be recommended and outcomes compared.

Radiographs of 100 fractures of the proximal humerus selected. A true anteroposterior, scapular lateral, and axillary radiograph taken for each fracture. 10 orthopaedic surgeons and 5 radiologists recruited as assessors, including 5 specialist registrars. Each given a printed description of both Neer and AO classifications, a goniometer and ruler. The assessment preceeded by short lecture. Radiographs could be manipulated digitally for size, contrast, brightness, orientation and the negative image displayed. We did not require assessors to determine subgroups for reasons of simplicity. Reproducibility and reliability analysed using Kappa statistical methods. Coefficients for agreement compared using the Student t test incorporating the standard errors of kappa for these groups. A comparison made between radiologists and surgeons, and then consultant orthopaedic surgeons and trainees.

In each case the AO/ASIF system was statistically (p< 0.01) more accurate.

Agreement was greater for less complex (one and two part, and type A) fractures.

Level of experience produced a statistically (p< 0.01) significant difference in accuracy. Specialty did not.

Our analysis comparing the Neer and AO systems uses the largest group of assessors reviewing the largest number of radiographs reported in the literature.

We concur with others in concluding that using these systems in isolation in determining treatment and comparing results following treatment cannot be recommended

For any fracture classification, a high level of intraobserver reproducibility and interobserver reliability is desirable. We compare the consistency of the AO and Frykman classifications for distal radius fractures using digitised radiographs of 100 fractures by 15 orthopaedic surgeons and 5 radiologists using a Picture Archiving and Communications System (PACS). The process was repeated 1 month later. Reproducibility moderate for both the AO and Frykman systems, reliability only fair for both the AO and Frykman systems. In each case reproducibilty using the Frykman system was slightly greater. The assessor’s level of experience and specialty was not seen to influence accuracy. The ability to electronically manipulate images does not appear to improve reliability compared to the use of traditional hard copies, and their sole use in describing these injuries is not recommended.

These fractures are common, approximately one sixth of all fractures and the most commonly occurring fractures in adults. Their multitude of eponyms hint at the difficulty in formulating a comprehensive and useable system. The Frykman classification is most popular, but limited- does not quantify displacement, shortening or the extent of comminution. The more comprehensive AO system is limited in its complexity with 27 possible subdivisions. Computerised tomography shown to give only marginal improvement in consistency of classification.

Radiographs of 100 fractures selected. Anteroposterior and lateral view for each. 15 orthopaedic surgeons and 5 radiologists recruited as assessors, including 5 specialist registrars. Each given a printed description of Frykman and AO classifications. Radiographs could be manipulated digitally. Intra and inter-observer reproducibility analysed. A comparison made comparing reproducibility between radiologists and surgeons, consultant orthopaedic surgeons and trainees. Statistical methods; analysis involves adjustment of observed proportion of agreement between observers by correction for the proportion of agreement that could have occurred by chance. Kappa coefficients compared using the Student t test incorporating standard errors of kappa for these groups.

Median interobserver reliability was fair for both the AO (kappa = 0.31, range 0.2 to 0.38) and Frykman (kappa = 0.36, range 0.30 to 0.43) systems. Median intraobserver reproducibility was moderate for both the AO (kappa = 0.45, range 0.42 to 0.48) and Frykman (kappa = 0.55, range 0.51 to 0.57) systems. In each case the Frykman system was statistically (p< 0.01) more accurate. Level of experience, or specialty was not seen to influence accuracy (p< 0.01).

Our results demonstrate that using them in isolation in determining treatment and comparing results following treatment cannot be recommended

The use of massive endoprostheses following bone tumour resection is well recognised. Where possible, joint salvage rather than joint replacement is usually attempted. However cases arise where there is insufficient bone following tumour resection to allow adequate fixation of a joint sparing prosthesis. We reporta series of 4 patients (aged 4–12), treated between 1994 and 2008, in which irradiated autologous bone has been combined with a diaphyseal or distal femoral replacement in order to preserve the native hip joint.

There were 3 cases of osteosarcoma and 1 case of Ewing‘s sarcoma. After a mean follow-up of 53.5 months (range 9–168), all four patients are alive without evidence of local recurrence or metastases. One implant was revised after 14 years following fracture of the extending component of the growing endoprosthesis. There have been no cases of loosening or periprosthetic fracture.

This is the first report of irradiated autologous bone with joint sparing endoprostheses in skeletally immature patients.

We undertook a retrospective review of 33 patients who underwent total femoral endoprosthetic replacement as limb salvage following excision of a malignant bone tumour. In 22 patients this was performed as a primary procedure following total femoral resection for malignant disease. Revision to a total femoral replacement was required in 11 patients following failed segmental endoprosthetic or allograft reconstruction. There were 33 patients with primary malignant tumours, and three had metastatic lesions. The mean age of the patients was 31 years (5 to 68). The mean follow-up was 4.2 years (9 months to 16.4 years). At five years the survival of the implants was 100%, with removal as the endpoint and 56% where the endpoint was another surgical intervention. At five years the patient survival was 32%. Complications included dislocation of the hip in six patients (18%), local recurrence in three (9%), peri-prosthetic fracture in two and infection in one. One patient subsequently developed pulmonary metastases. There were no cases of aseptic loosening or amputation. Four patients required a change of bushings. The mean Musculoskeletal Tumour Society functional outcome score was 67%, the mean Harris Hip Score was 70, and the mean Oxford Knee Score was 34.

Total femoral endoprosthetic replacement can provide good functional outcome without compromising patient survival, and in selected cases provides an effective alternative to amputation.

Purpose: To assess costs and health status outcomes following ACI and mosaicplasty used to treat chondral knee defects (1).

Methods: Patients received ACI or mosaicplasty at the Royal National Orthopaedic Hospital between 1997 and 2001, or, were on a waiting list for ACI. Resource use per patient was collected to two years post-operatively. A postal questionnaire collected sociodemographic characteristics, knee-related (Modified Cincinnati Knee Rating System) and general health status (EQ-5D).

Results: 53 ACI, 20 mosaicplasty and 22 patients waiting for ACI participated in this study. The average cost per patient was higher for ACI (£10,600: 95%CI £10,036-£11,214) than for mosaicplasty (£7,948: 95%CI £6,957-£9,243). Estimated average EQ-5D social tariff improvements for QALYs (quality adjusted life years) were 0.23 for ACI and 0.06 for mosaicplasty. Average costs per QALY were: £23,043 for ACI and £66,233 for mosaicplasty. The ICER (incremental cost effectiveness ratio) for providing ACI over mosaicplasty was £16,349. Post-operatively, ACI and mosaicplasty patients (combined) experienced better health status than patients waiting for ACI. ACI patients tended to have better health status outcomes than mosaicplasty patients, although this was not statistically significant.

Conclusions: Average costs were higher for ACI than for mosaicplasty. However, both the estimated cost per QALY and ICER fell beneath an implicit English funding threshold of £30,000 per QALY. To our knowledge this is the first study to compare the costs and utility of ACI with alternative ‘best’ treatments for people with chondral knee problems. Prospective studies are required to confirm these results.

Purpose: The purpose of this study was to use the thromboelastogram to determine whether autologous blood transfusion following primary total knee replacement surgery results in an alteration to systemic coagulation.

Methods: 44 patients were randomised to receive either Hartmann’s solution alone postoperatively (control group), or Hartmann’s solution and autologous blood at six hours (ABT group). Thromboelastogram measurements of systemic blood clotting were performed pre-operatively, and post operatively at 6h just prior to the commencement of the ABT, 6h 30mins, and 8h.

Results: At 8h post operation (2h post ABT), the ABT group when compared with the control group showed an earlier onset of coagulation (3.83 minutes versus 4.49 minutes, p=0.003) and the formation of a stronger clot as assessed by the TEG maximum amplitude (maximum clot strength 83.9mm versus 75.9mm, p< 0.001).

Conclusion: The transfusion of drained autologous blood following total knee replacement may lead to an exaggerated hypercoagulable postoperative state. Further investigation of this potentially serious consequence of autologous blood transfusion is required.

Background: Autologous chondrocyte implantation (ACI) was introduced over 15 years ago as a treatment for full-thickness chondral defects in the knee. Current understanding of ACI graft morphology and maturation in humans is limited. The aims of this study were determine the incidence of hyaline-like repair following ACI, and to clarify the relationship between repair morphology and clinical outcome.

Methods: A retrospective review of 194 ACI graft biopsies from 180 patients, and their clinical outcome was conducted. 154 Biopsies were performed 1 year after implantation and 40 biopsies were performed at 2 years. Three techniques of ACI implantation were used; Collagen covered ACI (ACI-C), periosteum covered ACI (ACI-P) and Matrix-Induced ACI (MACI).

Results: At 1 year, hyaline repair tissue was found in 48 (53%) ACI-C grafts, 7 (44%) ACI-P grafts, and 12 (36%) MACI grafts. The frequency of hyaline tissue found in biopsies performed at 2 years (84%) was significantly higher than those performed at 1 year (48.6%), p=0.0001, suggesting that grafts continue to remodel after the first year post implantation.

Clinical outcomes during the first two postoperative years did not vary according to repair morphology type, though hyaline repair was associated with better clinical outcomes beyond 2 years; At 1 year, good to excellent clinical scores were observed in 29 (78.4%) patients with hyaline-like repair, 23 (76.7%) patients with fibrohyaline repair, and 54 (74.0%) patients with fibrocartilage repair. By years 3 and 4 post-implantation, clinical scores further improved in patients with hyaline-like repair yet declined in those with fibrocartilage and fibrohyaline. The difference was significant at 3 years though not at 4 due to the small number of cases.

Conclusions: Achieving hyaline-like repair is critical to the longevity of cartilage repair. The finding of hyaline-like cartilage or fibrohyaline cartilage in 31 of 37 biopsies (84%) performed after 2 years is therefore encouraging and supports further use of the ACI technique.

Background: Autologous Chondrocyte Implantation (ACI) is widely used as a treatment for symptomatic chondral and osteochondral defects of the knee. Variations of the original periosteum cover technique include the use of porcine-derived type I/III collagen as a cover (ACI-C), and the use of a collagen bilayer seeded with chondrocytes (MACI).

Aim: To determine whether differences in clinical, arthroscopic and histological outcomes at 1 year exist between ACI-C and MACI techniques.

Methods: We have performed a prospective randomised comparison of ACI-C versus MACI for the treatment of symptomatic chondral defects of the knee on 91 patients of whom 44 received ACI-C and 47 received MACI grafts.

Results: Both treatments resulted in improvements of clinical scores after 1 year. Mean modified Cincinnati knee scores increased by 17.5 in the ACI-C group and 19.6 in the MACI group (p> 0.05). Arthroscopic assessments performed after 1 year demonstrated good to excellent ICRS graft repair scores in 79% of ACI-C grafts and 67% of MACI grafts. Hyaline-like or hyaline-like cartilage with fibrocartilage was found in the biopsies of 43% of ACI-C grafts and 36% of MACI grafts after 1 year. The rate of graft hypertrophy was 9% in the ACI-C group and 6% in the MACI group. The frequency of re-operation was 9% in each group.

Conclusions: We conclude that clinical, arthroscopic and histological outcomes are comparable for both ACI-C and MACI techniques. While the MACI technique is technically attractive, further long-term studies are required before widespread adoption of this new technique.

We investigated the prognostic indicators for collagen-covered autologous chondrocyte implantation (ACI-C) performed for symptomatic osteochondral defects of the knee.

We analysed prospectively 199 patients for up to four years after surgery using the modified Cincinnati score. Arthroscopic assessment and biopsy of the neocartilage was also performed whenever possible. The favourable factors for ACI-C include younger patients with higher pre-operative modified Cincinnati scores, a less than two-year history of symptoms, a single defect, a defect on the trochlea or lateral femoral condyle and patients with fewer than two previous procedures on the index knee. Revision ACI-C in patients with previous ACI and mosaicplasties which had failed produced significantly inferior clinical results. Gender (p = 0.20) and the size of the defect (p = 0.97) did not significantly influence the outcome.

Autologous chondrocyte implantation (ACI) is used widely as a treatment for symptomatic chondral and osteochondral defects of the knee. Variations of the original periosteum-cover technique include the use of porcine-derived type I/type III collagen as a cover (ACI-C) and matrix-induced autologous chondrocyte implantation (MACI) using a collagen bilayer seeded with chondrocytes. We have performed a prospective, randomised comparison of ACI-C and MACI for the treatment of symptomatic chondral defects of the knee in 91 patients, of whom 44 received ACI-C and 47 MACI grafts.

Both treatments resulted in improvement of the clinical score after one year. The mean modified Cincinnati knee score increased by 17.6 in the ACI-C group and 19.6 in the MACI group (p = 0.32). Arthroscopic assessments performed after one year showed a good to excellent International Cartilage Repair Society score in 79.2% of ACI-C and 66.6% of MACI grafts. Hyaline-like cartilage or hyaline-like cartilage with fibrocartilage was found in the biopsies of 43.9% of the ACI-C and 36.4% of the MACI grafts after one year. The rate of hypertrophy of the graft was 9% (4 of 44) in the ACI-C group and 6% (3 of 47) in the MACI group. The frequency of re-operation was 9% in each group.

We conclude that the clinical, arthroscopic and histological outcomes are comparable for both ACI-C and MACI. While MACI is technically attractive, further long-term studies are required before the technique is widely adopted.

Autologous chondrocyte implantation (ACI) is a technique used for the treatment of symptomatic osteochondral defects of the knee. A variation of the original periosteum membrane technique is the matrix-induced autologous chondrocyte implantation (MACI) technique. The MACI membrane consists of a porcine type-I/III collagen bilayer seeded with chondrocytes. Osteochondral defects deeper than 8 to 10 mm usually require bone grafting either before or at the time of transplantation of cartilage. We have used a variation of Peterson’s ACI-periosteum sandwich technique using two MACI membranes with bone graft which avoids periosteal harvesting. The procedure is suture-free and requires less operating time and surgical exposure. We performed this MACI-sandwich technique on eight patients, five of whom were assessed at six months and one year post-operatively using the modified Cincinnati knee, the Stanmore functional rating and the visual analogue pain scores.

All patients improved within six months with further improvement at one year. The clinical outcome was good or excellent in four after six months and one year. No significant graft-associated complications were observed. Our early results of the MACI-sandwich technique are encouraging although larger medium-term studies are required before there is widespread adoption of the technique.