We evaluated 535 consecutive primary cementless total knee replacements (TKR). The mean follow-up was 9.2 years (0.3 to 12.9) and information on implant survival was available for all patients. Patients were divided into two groups: 153 obese patients (BMI ≥ 30) and 382 non-obese (BMI < 30). A case-matched study was performed on the clinical and radiological outcome, comparing 50 knees in each group. We found significantly lower mean improvements in the clinical score (p = 0.044) and lower post-operative total clinical scores in the obese group (p = 0.041). There was no difference in the rate of radiological osteolysis or lucent lines, and no difference in alignment. Log rank test for survival showed no significant differences between the groups (p = 0.167), with a ten-year survival rate of 96.4% (95% confidence interval (CI) 92 to 99) in the obese and 98% (95% CI 96 to 99) in the non-obese.

The mid-term survival of TKR in the obese and the non-obese are comparable, but obesity appears to have a negative effect on the clinical outcome. However, good results and high patient satisfaction are still to be expected, and it would seem unreasonable to deny patients a TKR simply on the basis of a BMI indicating obesity.

Van Nes rotationplasty may be used for patients with congenital proximal focal femoral deficiency (PFFD). The lower limb is rotated to use the ankle and foot as a functional knee joint within a prosthesis. A small series of cases was investigated to determine the long-term outcome. At a mean of 21.5 years (11 to 45) after their rotationplasty, a total of 12 prosthetic patients completed the Short-Form (SF)-36, Faces Pain Scale-Revised, Harris hip score, Oswestry back pain score and Prosthetic Evaluation Questionnaires, as did 12 age- and gender-matched normal control participants. A physical examination and gait analysis, computerised dynamic posturography (CDP), and timed ‘Up & Go’ testing was also completed. Wilcoxon Signed rank test was used to compare each PFFD patient with a matched control participant with false discovery rate of 5%.

There were no differences between the groups in overall health and well-being on the SF-36. Significant differences were seen in gait parameters in the PFFD group. Using CDP, the PFFD group had reduced symmetry in stance, and reduced end point and maximum excursions.

Patients who had undergone Van Nes rotationplasty had a high level of function and quality of life at long-term follow-up, but presented with significant differences in gait and posture compared with the control group.

Cite this article: Bone Joint J 2013;95-B:192–8.

The Cementless Oxford Unicompartmental Knee Replacement (OUKR) was developed to address problems related to cementation, and has been demonstrated in a randomised study to have similar clinical outcomes with fewer radiolucencies than observed with the cemented device. However, before its widespread use it is necessary to clarify contraindications and assess the complications. This requires a larger study than any previously published.

We present a prospective multicentre series of 1000 cementless OUKRs in 881 patients at a minimum follow-up of one year. All patients had radiological assessment aligned to the bone–implant interfaces and clinical scores. Analysis was performed at a mean of 38.2 months (19 to 88) following surgery. A total of 17 patients died (comprising 19 knees (1.9%)), none as a result of surgery; there were no tibial or femoral loosenings. A total of 19 knees (1.9%) had significant implant-related complications or required revision. Implant survival at six years was 97.2%, and there was a partial radiolucency at the bone–implant interface in 72 knees (8.9%), with no complete radiolucencies. There was no significant increase in complication rate compared with cemented fixation (p = 0.87), and no specific contraindications to cementless fixation were identified.

Cementless OUKR appears to be safe and reproducible in patients with end-stage anteromedial osteoarthritis of the knee, with radiological evidence of improved fixation compared with previous reports using cemented fixation.

Cite this article: Bone Joint J 2013;95-B:181–7.

We report the results of using a combination of fixator-assisted nailing with lengthening over an intramedullary nail in patients with tibial deformity and shortening. Between 1997 and 2007, 13 tibiae in nine patients with a mean age of 25.4 years (17 to 34) were treated with a unilateral external fixator for acute correction of deformity, followed by lengthening over an intramedullary nail with a circular external fixator applied at the same operating session. At the end of the distraction period locking screws were inserted through the intramedullary nail and the external fixator was removed.

The mean amount of lengthening was 5.9 cm (2 to 8). The mean time of external fixation was 90 days (38 to 265). The mean external fixation index was 15.8 days/cm (8.9 to 33.1) and the mean bone healing index was 38 days/cm (30 to 60).

One patient developed an equinus deformity which responded to stretching and bracing. Another developed a drop foot due to a compartment syndrome, which was treated by fasciotomy. It recovered in three months. Two patients required bone grafting for poor callus formation.

We conclude that the combination of fixator-assisted nailing with lengthening over an intramedullary nail can reduce the overall external fixation time and prevent fractures and deformity of the regenerated bone.

We systematically reviewed the published literature on the complications of closing wedge high tibial osteotomy for the treatment of unicompartmental osteoarthritis of the knee. Publications were identified using the Cochrane Library, MEDLINE, EMBASE and CINAHL databases up to February 2012. We assessed randomised (RCTs), controlled group clinical (CCTs) trials, case series in publications associated with closing wedge osteotomy of the tibia in patients with osteoarthritis of the knee and finally a Cochrane review. Many of these trials included comparative studies (opening wedge versus closing wedge) and there was heterogeneity in the studies that prevented pooling of the results.

The Morscher-Spotorno (MS-30) femoral stem is a stainless-steel, straight, three-dimensionally tapered, collarless implant for cemented fixation in total hip replacement.

We report the results at ten years of a consecutive series of 124 total hip replacements in 121 patients with the matt-surfaced MS-30 stem and an alumina ceramic head of 28-mm diameter. All the stems were fixed with Palacos bone cement with gentamicin using a modern cementing technique. They were combined with an uncemented, press-fit cup. The mean period of observation was 10.2 years (8.3 to 12.1) and no patient was lost to follow-up. Twenty-seven patients (22%) died with the implant in situ. Nine could only be interviewed by telephone. We included 85 patients with 88 hips in the clinical and radiological follow-up examinations.

None of the stems or cups had been revised. The Harris hip score was excellent or good in 97% (85 hips) and moderate in 3% (three hips). Radiologically, six hips (6.8%) had osteolysis adjacent to the stem, mostly in Gruen zone 7. Twenty (22.7%) showed one or more radiolucent lines. Twenty-two stems (25%) had subsided by 2 mm to 5 mm. In these cases two showed osteolysis (9.1%) with subsidence and four without (6.1%). Radiolucent lines were seen in seven with migration (31.8%) and in 13 without (19.7%). No infections and no acetabular osteolysis were observed.

The clinical results were excellent with survivorship after ten years of 100% and only a slightly statistically non-significant higher rate of osteolysis and radiolucency in cases of subsidence.

It is unclear whether there is a limit to the amount of distal bone required to support fixation of supracondylar periprosthetic femoral fractures. This retrospective multicentre study evaluated lateral locked plating of periprosthetic supracondylar femoral fractures and compared the results according to extension of the fracture distal with the proximal border of the femoral prosthetic component.

Between 1999 and 2008, 89 patients underwent lateral locked plating of a supracondylar periprosthetic femoral fracture, of whom 61 patients with a mean age of 72 years (42 to 96) comprising 53 women, were available after a minimum follow-up of six months or until fracture healing. Patients were grouped into those with fractures located proximally (28) and those with fractures that extended distal to the proximal border of the femoral component (33).

Delayed healing and nonunion occurred respectively in five (18%) and three (11%) of more proximal fractures, and in two (6%) and five (15%) of the fractures with distal extension (p = 0.23 for delayed healing; p = 0.72 for nonunion, Fisher’s exact test). Four construct failures (14%) occurred in more proximal fractures, and three (9%) in fractures with distal extension (p = 0.51). Of the two deep infections that occurred in each group, one resolved after surgical debridement and antibiotics, and one progressed to a nonunion.

Extreme distal periprosthetic supracondylar fractures of the femur are not a contra-indication to lateral locked plating. These fractures can be managed with internal fixation, with predictable results, similar to those seen in more proximal fractures.

We report the use of a free vascularised iliac bone graft in the treatment of 21 patients (19 men and 2 women) with an avascular nonunion of the scaphoid in which conventional bone grafting had previously failed. The mean age of the patients was 32 years (23 to 46) and the dominant wrist was affected in 14. The mean interval from fracture to the vascularised bone grafting was 39 months (9 to 62). Pre-operative MRI showed no contrast enhancement in the proximal fragment in any patient. Fracture union was assessed radiologically or with CT scans if the radiological appearances were inconclusive.

At a mean follow-up of 5.6 years (2 to 11) union was obtained in 16 patients. The remaining five patients with a persistent nonunion continued to experience pain, reduced grip strength and limited range of wrist movement. In the successfully treated patients the grip strength and range of movement did not recover to match the uninjured side.

Prevention of progressive carpal collapse, the absence of donor site morbidity, good subjective results and pain relief, justifies this procedure in the treatment of recalcitrant nonunion of the scaphoid.

Salvage of a failed total ankle replacement is technically challenging and although a revision procedure may be desirable, a large amount of bone loss or infection may preclude this. Arthrodesis can be difficult to achieve and is usually associated with considerable shortening of the limb.

We describe a technique for restoring talar height using an allograft from the femoral head compressed by an intramedullary nail. Three patients with aseptic loosening were treated successfully by this method with excellent symptomatic relief at a mean follow-up of 32 months (13 to 50).

We compared lower limb coronal alignment measurements obtained pre- and post-operatively with long-leg radiographs and computer navigation in patients undergoing primary total knee replacement (TKR). A series of 185 patients had their pre- and post-implant radiological and computer-navigation system measurements of coronal alignment compared using the Bland-Altman method. The study included 81 men and 104 women with a mean age of 68.5 years (32 to 87) and a mean body mass index of 31.7 kg/m² (19 to 49). Pre-implant Bland–Altman limits of agreement were -9.4° to 8.6° with a repeatability coefficient of 9.0°. The Bland–Altman plot showed a tendency for the radiological measurement to indicate a higher level of pre-operative deformity than the corresponding navigation measurement. Post-implant limits of agreement were -5.0° to 5.4° with a repeatability coefficient of 5.2°. The tendency for valgus knees to have greater deformity on the radiograph was still seen, but was weaker for varus knees.

The alignment seen or measured intra-operatively during TKR is not necessarily the same as the deformity seen on a standing long-leg radiograph either pre- or post-operatively. Further investigation into the effect of weight-bearing and surgical exposure of the joint on the mechanical femorotibial angle is required to enable the most appropriate intra-operative alignment to be selected.

The original forged Müller straight stem (CoNiCr) has shown excellent ten- to 15-year results. We undertook a long-term survival analysis with special emphasis on radiological changes within a 20-year period of follow-up.

In all, 165 primary total hip replacements, undertaken between July 1984 and June 1987 were followed prospectively. Clinical follow-up included a standardised clinical examination, and radiological assessment was based on a standardised anteroposterior radiograph of the pelvis, which was studied for the presence of osteolysis, debonding and cortical atrophy.

Survival of the stem with revision for any reason was 81% (95% confidence interval (CI), 76 to 86) at 20 years and for aseptic loosening 87% (95% CI, 82 to 90). At the 20-year follow-up, 15 of the surviving 36 stems showed no radiological changes. Debonding (p = 0.005), osteolysis (p = 0.003) and linear polyethylene wear (p = 0.016) were associated with aseptic loosening, whereas cortical atrophy was not associated with failure (p = 0.008).

The 20-year results of the Müller straight stem are comparable to those of other successful cemented systems with similar follow-up. Radiological changes are frequently observed, but with a low incidence of progression, and rarely result in revision. Cortical atrophy appears to be an effect of ageing and not a sign of loosening of the femoral component.

We present a comparison of patient-reported outcomes (PROMs) in relation to patient age, in patients who had received a total (TKR) or unicompartmental knee replacement (UKR). The outcome was evaluated using the Oxford knee score (OKS), EuroQol (EQ-5D) and satisfaction scores. Patients aged 65 to 84 years demonstrated better pre-operative function scores than those aged < 65 years (OKS, p = 0.03; EQ-5D, p = 0.048) and those aged ≥ 85 years (OKS, p = 0.03). Post-operative scores were comparable across age groups, but a linear trend for greater post-operative improvement in OKS and EQ-5D was seen with decreasing age (p < 0.033). The overall mean satisfaction score at six months was 84.9, but those aged <  55 years exhibited a lower mean level of satisfaction (78.3) compared with all other age groups (all p < 0.031). The cumulative overall two-year revision rate was 1.3%. This study demonstrates that good early outcomes, as measured by the OKS and EQ-5D, can be anticipated following knee replacement regardless of the patient’s age, although younger patients gain greater improvement. However, the lower satisfaction in those aged < 55 years is a concern, and suggests that outcome is not fully encapsulated by the OKS and EQ-5D evaluation, and raises the question whether the OKS alone is an appropriate measure of pain and function in younger, more active individuals.

Cite this article: Bone Joint J 2013;95-B:38–44.

We investigated 60 patients (89 feet) with a mean age of 64 years (61 to 67) treated for congenital clubfoot deformity, using standardised weight-bearing radiographs of both feet and ankles together with a functional evaluation. Talocalcaneal and talonavicular relationships were measured and the degree of osteo-arthritic change in the ankle and talonavicular joints was assessed. The functional results were evaluated using a modified Laaveg-Ponseti score. The talocalcaneal (TC) angles in the clubfeet were significantly lower in both anteroposterior (AP) and lateral projections than in the unaffected feet (p < 0.001 for both views). There was significant medial subluxation of the navicular in the clubfeet compared with the unaffected feet (p < 0.001). Severe osteoarthritis in the ankle joint was seen in seven feet (8%) and in the talonavicular joint in 11 feet (12%). The functional result was excellent or good (≥ 80 points) in 29 patients (48%), and fair or poor (< 80 points) in 31 patients (52%). Patients who had undergone few (0 to 1) surgical procedures had better functional outcomes than those who had undergone two or more procedures (p < 0.001). There was a significant correlation between the functional result and the degree of medial subluxation of the navicular (p < 0.001, r² = 0.164), the talocalcaneal angle on AP projection (p < 0.02, r2 = 0.025) and extent of osteoarthritis in the ankle joint (p < 0.001).

We conclude that poor functional outcome in patients with congenital clubfoot occurs more frequently in those with medial displacement of the navicular, osteoarthritis of the talonavicular and ankle joints, and a low talocalcaneal angle on the AP projection, and in patients who have undergone two or more surgical procedures. However, the ankle joint in these patients appeared relatively resistant to the development of osteoarthritis.

The purpose of this study was to measure the radiological parameters of femoral component alignment of the Oxford Phase 3 unicompartmental knee replacement (UKR), and evaluate their effect on clinical outcome. Multiple regression analysis was used to examine the relative contributions of the radiological assessment of femoral component alignment in 189 consecutive UKRs performed by a single surgeon. The American Knee Society scores were compared between groups, defined as being within or outside recommended tolerances of the position of the femoral component. For the flexion/extension position 21 UKRs (11.1%) lay outside the recommended limits, and for posterior overhang of the femoral component nine (4.8%) lay outside the range. The pre-operative hip/knee/ankle (HKA) angle, narrowest canal distance from the distal femoral entry point of the alignment jig and coronal entry-point position had significant effects on the flexion/extension position. Pre-operative HKA angle had a significant influence on posterior overhang of the femoral component. However, there was no significant difference in American Knee Society scores relative to the position of the femoral component.

Malunion is the most common complication of the distal radius with many modalities of treatment available for such a problem. The use of bone grafting after an osteotomy is still recommended by most authors. We hypothesised that bone grafting is not required; fixing the corrected construct with a volar locked plate helps maintain the alignment, while metaphyseal defect fills by itself. Prospectively, we performed the procedure on 30 malunited dorsally-angulated radii using fixed angle volar locked plates without bone grafting. At the final follow-up, 22 wrists were available. Radiological evidence of union, correction of the deformity, clinical and functional improvement was achieved in all cases. Without the use of bone grafting, corrective open wedge osteotomy fixed by a volar locked plate provides a high rate of union and satisfactory functional outcomes.

Metal-on-metal hip resurfacing is commonly performed for osteoarthritis in young active patients. We have observed cystic or solid masses, which we have called inflammatory pseudotumours, arising around these devices. They may cause soft-tissue destruction with severe symptoms and a poor outcome after revision surgery. The aim of this study was to determine the incidence of and risk factors for pseudotumours that are serious enough to require revision surgery.

Since 1999, 1419 metal-on-metal hip resurfacings have been implanted by our group in 1224 patients; 1.8% of the patients had a revision for pseudotumour. In this series the Kaplan-Meier cumulative revision rate for pseudotumour increased progressively with time. At eight years, in all patients, it was 4% (95% confidence interval (CI) 2.2 to 5.8). Factors significantly associated with an increase in revision rate were female gender (p < 0.001), age under 40 (p = 0.003), small components (p = 0.003), and dysplasia (p = 0.019), whereas implant type was not (p = 0.156). These factors were inter-related, however, and on fitting a Cox proportional hazard model only gender (p = 0.002) and age (p = 0.024) had a significant independent influence on revision rate; size nearly reached significance (p = 0.08). Subdividing the cohort according to significant factors, we found that the revision rate for pseudotumours in men was 0.5% (95% CI 0 to 1.1) at eight years wheras in women over 40 years old it was 6% (95% CI 2.3 to 10.1) at eight years and in women under 40 years it was 13.1% at six years (95% CI 0 to 27) (p < 0.001).

We recommend that resurfacings are undertaken with caution in women, particularly those under 40 years of age but they remain a good option in young men. Further work is required to understand the aetiology of pseudotumours so that this complication can be avoided.

Stems improve the mechanical stability of tibial components in total knee replacement (TKR), but come at a cost of stress shielding along their length. Their advantages include resistance to shear, reduced tibial lift-off and increased stability by reducing micromotion. Longer stems may have disadvantages including stress shielding along the length of the stem with associated reduction in bone density and a theoretical risk of subsidence and loosening, peri-prosthetic fracture and end-of-stem pain. These features make long stems unattractive in the primary TKR setting, but often desirable in revision surgery with bone loss and instability. In the revision scenario, stems are beneficial in order to convey structural stability to the construct and protect the reconstruction of bony defects. Cemented and uncemented long stemmed implants have different roles depending on the nature of the bone loss involved.

This review discusses the biomechanics of the design of tibial components and stems to inform the selection of the component and the technique of implantation.

Radiological assessment of total and unicompartmental knee replacement remains an essential part of routine care and follow-up. Appreciation of the various measurements that can be identified radiologically is important. It is likely that routine plain radiographs will continue to be used, although there has been a trend towards using newer technologies such as CT, especially in a failing knee, where it provides more detailed information, albeit with a higher radiation exposure.

The purpose of this paper is to outline the radiological parameters used to evaluate knee replacements, describe how these are measured or classified, and review the current literature to determine their efficacy where possible.

Between 2005 and 2010 ten consecutive children with high-energy open diaphyseal tibial fractures were treated by early reduction and application of a programmable circular external fixator. They were all male with a mean age of 11.5 years (5.2 to 15.4), and they were followed for a mean of 34.5 months (6 to 77). Full weight-bearing was allowed immediately post-operatively. The mean time from application to removal of the frame was 16 weeks (12 to 21). The mean deformity following removal of the frame was 0.15° (0° to 1.5°) of coronal angulation, 0.2° (0° to 2°) sagittal angulation, 1.1 mm (0 to 10) coronal translation, and 0.5 mm (0 to 2) sagittal translation. All patients achieved consolidated bony union and satisfactory wound healing. There were no cases of delayed or nonunion, compartment syndrome or neurovascular injury. Four patients had a mild superficial pin site infection; all settled with a single course of oral antibiotics. No patient had a deep infection or re-fracture following removal of the frame. The time to union was comparable with, or better than, other published methods of stabilisation for these injuries. The stable fixator configuration not only facilitates management of the accompanying soft-tissue injury but enables anatomical post-injury alignment, which is important in view of the limited remodelling potential of the tibia in children aged > ten years. Where appropriate expertise exists, we recommend this technique for the management of high-energy open tibial fractures in children.