Aims. The aim of this study was to describe implant and patient-reported outcome in patients with a unilateral transfemoral amputation (TFA) treated with a bone-anchored, transcutaneous prosthesis. Methods. In this cohort study, all patients with a unilateral TFA treated with the Osseointegrated Prostheses for the Rehabilitation of Amputees (OPRA) implant system in Sahlgrenska University Hospital, Gothenburg, Sweden, between January 1999 and December 2017 were included. The cohort comprised 111 patients (78 male (70%)), with a mean age 45 years (17 to 70). The main reason for amputation was trauma in 75 (68%) and tumours in 23 (21%). Patients answered the Questionnaire for Persons with Transfemoral Amputation (Q-TFA) before treatment and at two, five, seven, ten, and 15 years’ follow-up. A prosthetic activity grade was assigned to each patient at each timepoint. All mechanical complications, defined as fracture, bending, or wear to any part of the implant system resulting in removal or change, were recorded. Results. The Q-TFA scores at two, five, seven, and ten years showed significantly more prosthetic use, better mobility, fewer problems, and an improved global situation, compared with baseline. The survival rate of the osseointegrated implant part (the fixture) was 89% and 72% after seven and 15 years, respectively. A total of 61 patients (55%) had mechanical complications (mean 3.3 (SD 5.76)), resulting in exchange of the percutaneous implant parts. There was a positive relationship between a higher activity grade and the number of mechanical complications. Conclusion. Compared with before treatment, the patient-reported outcome was significantly better and remained so over time. Although osseointegration and the ability to transfer loads over a 15-year period have been demonstrated, a large number of mechanical failures in the external implant parts were found. Since these were related to higher activity, restrictions in activity and improvements to the mechanical properties of the implant system are required. Cite this article: Bone Joint J 2020;102-B(1):55–63

Conventional amputation prostheses rely on the attachment of the socket to the stump, which may lead to soft-tissue complications. Intraosseous transcutaneous amputation prostheses (ITAPs) allow direct loading of the skeleton, but their success is limited by infection resulting from breaching of the skin at the interface with the implant. Keratinocytes provide the skin’s primary barrier function, while hemidesmosomes mediate their attachment to natural ITAP analogues. Keratinocytes must attach directly to the surface of the implant. We have assessed the proliferation, morphology and attachment of keratinocytes to four titaniumalloy surfaces in order to determine the optimal topography in vitro. We used immunolocalisation of adhesion complex components, scanning electron microscopy and transmission electron microscopy to assess cell parameters. We have shown that the proliferation, morphology and attachment of keratinocytes are affected by the surface topography of the biomaterials used to support their growth. Smoother surfaces improved adhesion. We postulate that a smooth topography at the point of epithelium-ITAP contact could increase attachment in vivo, producing an effective barrier of infection

The transcutaneous oxygen pressure (tcPO2) was measured by a polarographic technique in the legs of 161 volunteers and compared with the levels found in 62 patients with ischaemic skin due to peripheral vascular disease. The results show that the tcPO2 was related to the degree of ischaemia and, in many cases, was a more accurate guide to the viability of the skin than clinical assessment. Measurement of the transcutaneous oxygen pressure in the leg at the site of amputation in 24 patients with peripheral vascular disease showed that a preoperative level greater than 40 millimetres of mercury at an electrode temperature of 44 degrees Celsius was necessary for the skin of the stump to heal. The technique is simple, non-invasive and reliable. The tcPO2 accurately reflects the physiological and pathological changes in the circulation of the skin. It has potential in many fields of surgery where careful assessment of the viability of the skin is necessary

Aims. The Intraosseous Transcutaneous Amputation Prosthesis (ITAP) may improve quality of life for amputees by avoiding soft-tissue complications associated with socket prostheses and by improving sensory feedback and function. It relies on the formation of a seal between the soft tissues and the implant and currently has a flange with drilled holes to promote dermal attachment. Despite this, infection remains a significant risk. This study explored alternative strategies to enhance soft-tissue integration. Materials and Methods. The effect of ITAP pins with a fully porous titanium alloy flange with interconnected pores on soft-tissue integration was investigated. The flanges were coated with fibronectin-functionalised hydroxyapatite and silver coatings, which have been shown to have an antibacterial effect, while also promoting viable fibroblast growth in vitro. The ITAP pins were implanted along the length of ovine tibias, and histological assessment was undertaken four weeks post-operatively. Results. The porous titanium alloy flange reduced epithelial downgrowth and increased soft-tissue integration compared with the current drilled flange. The addition of coatings did not enhance these effects. Conclusion. These results indicate that a fully porous titanium alloy flange has the potential to increase the soft-tissue seal around ITAP and reduce susceptibility to infection compared with the current design. Cite this article: Bone Joint J 2017;99-B:393–400

We studied the effect of transcutaneous electrical nerve stimulation (TENS) on stump healing and postoperative and late phantom pain after major amputations of the lower limb. A total of 51 patients were randomised to one of three postoperative treatment regimens: sham TENS and chlorpromazine medication, sham TENS only, and active low frequency TENS. There were fewer re-amputations and more rapid stump healing among below-knee amputees who had received active TENS. Sham TENS had a considerable placebo effect on pain. There were, however, no significant differences in the analgesic requirements or reported prevalence of phantom pain between the groups during the first four weeks. The prevalence of phantom pain after active TENS was significantly lower after four months but not after more than one year

The predictive value of the pedal transcutaneous oxygen tension (tcPO2) and of the distal systolic blood pressure (SBP) in forecasting the necessity for later amputation has been studied in 26 patients suffering from severe chronic ischaemia of the lower limbs. In all these patients vascular surgery had failed or not been possible, and they were threatened by amputation; they suffered from trophic lesions, or pain at rest, or both. The great toe SBP averaged 10 mmHg (range 0 to 60 mmHg) and the pedal tcPO2 10 mmHg (range 2 to 45 mmHg). After six minutes of oxygen inhalation there was an increase in pedal tcPO2 of 9 mmHg (0 to 50 mmHg). After a follow-up period averaging 7 months (range 10 days to 13 months), 13 patients underwent an amputation and nine (five of whom had been amputated) died. The great toe SBP in the patients who required amputation was initially lower than in those who did not. The pedal tcPO2 also was lower in amputated than in non-amputated patients. There was no amputation in the group showing an increase of at least 10 mmHg after six minutes of oxygen inhalation; and conversely, all patients in whom the pedal tcPO2 increased less than 10 mmHg were amputated. Thus increase in the pedal tcPO2 after oxygen inhalation appears the best criterion for estimating the prognosis of severely ischaemic limbs

A consecutive series of 31 displaced fractures of the proximal humerus were randomly selected for treatment either by closed manipulation or by transcutaneous reduction and external fixation. Follow-up assessed the quality of reduction and healing as well as the functional outcome. The external fixation method gave better reduction, safer healing and superior function

In 42 amputations (28 below-knee and 14 above-knee), healing of the stump was found to correlate with the pre-operative transcutaneous oxygen pressure (tcPO2) measured at the planned site of incision. Of 31 patients with a tcPO2 of 30 mmHg or more, 27 healed primarily, three had delayed healing and one failed to heal; of seven patients with values between 20 and 30 mmHg three healed primarily and four had delayed healing; and all four patients with a value below 20 mmHg had stumps which failed to heal and needed reamputation. It is concluded that a tcPO2 of 20 mmHg or more at the intended site of amputation indicates that the wound will heal

The success of long-term transcutaneous implants depends on dermal attachment to prevent downgrowth of the epithelium and infection. Hydroxyapatite (HA) coatings and fibronectin (Fn) have independently been shown to regulate fibroblast activity and improve attachment. In an attempt to enhance this phenomenon we adsorbed Fn onto HA-coated substrates. Our study was designed to test the hypothesis that adsorption of Fn onto HA produces a surface that will increase the attachment of dermal fibroblasts better than HA alone or titanium alloy controls. . Iodinated Fn was used to investigate the durability of the protein coating and a bioassay using human dermal fibroblasts was performed to assess the effects of the coating on cell attachment. Cell attachment data were compared with those for HA alone and titanium alloy controls at one, four and 24 hours. Protein attachment peaked within one hour of incubation and the maximum binding efficiency was achieved with an initial droplet of 1000 ng. We showed that after 24 hours one-fifth of the initial Fn coating remained on the substrates, and this resulted in a significant, three-, four-, and sevenfold increase in dermal fibroblast attachment strength compared to uncoated controls at one, four and 24 hours, respectively

Aims

As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach.

The viability of three incisions for knee arthroplasty were analysed by transcutaneous estimation of the skin oxygen tension. Wound viability was found to be significantly reduced following knee arthroplasty. The lateral wound edge is more hypoxic than the medial, but there were no significant differences between the three incisions

A new technique for the treatment of displaced fractures of the proximal humerus is described. Twelve fractures in 11 patients were managed by transcutaneous reduction using a Steinmann pin, and external fixation with a Hoffmann-type neutralising bar connected to two half-pins in the humeral head and three half-pins in the shaft. The pins were removed after four weeks. Two patients sustained redisplacement after a further injury, but in the others reduction was maintained. Two cases of pin-track infection resolved after antibiotics, but delayed union resulted. There were no neurovascular injuries and at follow-up of 6 to 12 months no refractures had been seen. The early functional results were excellent or satisfactory in nine cases

One hundred and seventy-four consecutive patients with symptoms of derangement of the knee were examined with an arthroscope under local anaesthesia using a continuous pressure-irrigation system. A 0.2 per cent prilocaine-saline solution was used as irrigation fluid. In the first 19 patients the serum level of prilocaine was monitored for six hours after the start of irrigation. Eighteen of the 174 patients had a transcutaneous partial meniscectomy at the same time as the examination. All the patients tolerated the examination well. The distension of the knee produced by the pressure-irrigation system provided a high degree of diagnostic accuracy. The serum levels of prilocaine were low throughout the monitoring period reaching a mean peak value of 0.28 micrograms per millilitre after one hour. There were no adverse side-effects. This technique provides a safe and efficient method to meet the increasing demands of arthroscopic procedures of the knee

We have investigated whether the thigh tourniquet used during total knee replacement (TKR) influenced the development of postoperative wound hypoxia and was a cause of delayed wound healing. We allocated randomly 31 patients (31 TKRs) to one of three groups: 1) no tourniquet; 2) tourniquet inflated at low pressure (about 225 mmHg); and 3) tourniquet inflated to high pressure of about 350 mmHg. Wound oxygenation was measured using transcutaneous oxygen electrodes. In the first week after surgery, patients with a tourniquet inflated to a high pressure had greater wound hypoxia than those with a low pressure. Those without a tourniquet also had wound hypoxia, but the degree and duration were less pronounced than in either of the groups with a tourniquet. Use of a tourniquet during TKR can increase postoperative wound hypoxia, especially when inflated to high pressures. Our findings may be relevant to wound healing and the development of wound infection

Aims

This study describes the Osseointegration Group of Australia’s Accelerated Protocol two-stage strategy (OGAAP-1) for the osseointegrated reconstruction of amputated limbs.

The purpose of this study was to evaluate the effect of various non-operative modalities of treatment (transcutaneous electrical nerve stimulation (TENS); neuromuscular electrical stimulation (NMES); insoles and bracing) on the pain of osteoarthritis (OA) of the knee.

We conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify the therapeutic options which are commonly adopted for the management of osteoarthritis (OA) of the knee.

The outcome measurement tools used in the different studies were the visual analogue scale and The Western Ontario and McMaster Universities Arthritis Index pain index: all pain scores were converted to a 100-point scale.

A total of 30 studies met our inclusion criteria: 13 on insoles, seven on TENS, six on NMES, and four on bracing. The standardised mean difference (SMD) in pain after treatment with TENS was 1.796, which represented a significant reduction in pain. The significant overall effect estimate for NMES on pain was similar to that of TENS, with a SMD of 1.924. The overall effect estimate of insoles on pain was a SMD of 0.992. The overall effect of bracing showed a significant reduction in pain of 1.34.

Overall, all four non-operative modalities of treatment were found to have a significant effect on the reduction of pain in OA of the knee.

This study shows that non-operative physical modalities of treatment are of benefit when treating OA of the knee. However, much of the literature reviewed evaluates studies with follow-up of less than six months: future work should aim to evaluate patients with longer follow-up.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):89–94.

Aims

The surgical management of ankle arthritis with tibiotalar arthrodesis is known to alter gait, as compared with normal ankles. The purpose of this study was to assess post-operative gait function with gait before arthrodesis.

Aims

Patients undergoing femoral lengthening by external fixation tolerate treatment less well when compared to tibial lengthening. Lengthening of the femur with an intramedullary device may have advantages.

Complex regional pain syndrome is characterised by an exaggerated response to injury in a limb with intense prolonged pain, vasomotor disturbance, delayed functional recovery and trophic changes. This review describes the current knowledge of the condition and outlines the methods of treatment available with particular emphasis on the knee.

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