Osseointegrated prostheses for femur amputees.

Osseointegrated implants is a surgical treatment permitting a direct skeletal attachment of an external prosthesis. It is a treatment for healthy transfemoral amputated patients who cannot tolerate or use a socket prosthesis, thereby alleviating related issues with poor fit, skin problems or discomfort. This review provides a summary of the indications and contraindications for surgery, the most common implants and reported outcomes.

[Fracture-related infections].

Fracture-related infections (FRI) is a challenging complication with a high risk of devastation outcomes for the patients. Diagnosing FRI is often difficult, and treatment frequently requires the effort of a multidisciplinary team. Recently, an international consensus group of experts from various scientific and medical organisations has published standardised guidelines of diagnosis and treatment. This review provides a summary of the latest studies and the general principles with respect to diagnosis, treatment and aftercare of patients with FRI.

Septic arthritis and osteomyelitis of the pubic symphysis - a retrospective study of 26 patients.

Introduction: Septic arthritis and osteomyelitis of the pubic symphysis (SAS) are rare conditions with nonspecific symptoms leading to diagnostic delay and treatment. Aim: We draw awareness to this condition elucidating the diagnostic procedures, surgical intervention and antibiotic management. Methods: This entail a retrospective follow-up study of 26 consecutive patients, median age of 71 years (range: 48-89) surgically treated for septic arthritis of the pubic symphysis between 2009 and 2020. Patient files, diagnostic imaging and bacterial cultures were evaluated. Results: Before diagnosed with SAS, 21 of the patients had previous pelvic surgery (16 due to malign conditions, 5 due to benign conditions), while 5 of the patients were not previously operated. Median follow-up period after SAS surgery was 18.5 months (range: 8 to 144.5 months). Dominating symptoms were severe suprapubic/pubic pain ( n   =  26), gait difficulties ( n   =  10) and intermittent fever ( n   =  9). Diagnostic delay was between 1 and 12 months. The diagnostic imaging included magnetic resonance imaging (MRI) ( n   =  24), computer tomography (CT) ( n   =  17) and/or PET-CT ( n   =  10), predominantly displaying bone destruction/erosion of the symphysis ( n   =  13), abscess ( n   =  12) and/or fistula ( n   =  5) in the adjacent muscles. All patients underwent surgical debridement with resection of the symphysis and received a minimum of 6 weeks antibiotic treatment. Fourteen patients presented with monocultures and 4 patients with polycultures. Five patients underwent at least one revision surgery. Twenty-three patients experienced postoperative pain relief at 6 weeks follow-up, and 19 patients were ambulant without walking aids. Conclusion: SAS are rare conditions and should be suspected in patients with infection, pubic pain and impaired gait, especially after pelvic surgery. Bone infection, abscess and fistula near the symphysis can be visualized with proper imaging, most frequently with MRI. For most patients in this cohort surgical debridement combined with a minimum of 6 weeks antibiotic treatment resulted in pain relief, improved walking ability and a low recurrence rate.

Changes in periprosthetic bone mineral density and bone turnover markers after osseointegrated implant surgery: A cohort study of 20 transfemoral amputees with 30-month follow-up.

BACKGROUND: The osseointegrated implant system is a treatment option for people with transfemoral amputation, but implant removal is not uncommon. The association between bone mineral density changes or bone turnover markers and the need for implant removal has not previously been investigated. OBJECTIVES: The aim was to evaluate changes in bone mineral density and bone turnover markers in people with transfemoral amputations treated with osseointegrated implants. STUDY DESIGN: This is a prospective cohort study. METHODS: Nineteen patients were followed up for 30 months or until implant removal. Bone mineral density was measured in the lumbar spine, proximal femur and seven periprosthetic regions. 25-hydroxyvitamin (D2 + D3), parathyroid hormone, N-terminal propeptide of type-I procollagen, C-telopeptide of type-I collagen, bone-specific alkaline phosphatase and osteocalcin were measured in blood samples. RESULTS: Four fixtures and three abutments were removed. Patients with removed implants had a decreased bone mineral density in the seven periprosthetic regions between 27% (95% confidence interval = 6; 43) and 38% (95% confidence interval = 19; 52) at 30-month follow-up compared to baseline (p < 0.02), whereas bone mineral density around non-removed implants normalized to baseline values (p > 0.08). C-telopeptide of type-I collagen was significantly different between the groups at 18- and 24-month follow-up (p < 0.05). None of the measured variables were significant predictors of implant removal (p > 0.07). CONCLUSION: Implant removal was associated with loss of periprosthetic bone mineral density and increase in C-telopeptide of type-I collagen in the years following osseointegrated surgery. CLINICAL RELEVANCE: This study offers new insight into changes in bone mineral density and bone turnover markers that precipitate aseptic or septic osseointegrated implant removal. Results of this study could contribute to clinical guidelines for monitoring rehabilitation progress and implant removal through dual-energy X-ray absorptiometry or surrogate markers like C-telopeptide of type-I collagen.

Does migration of osseointegrated implants for transfemoral amputees predict later revision? A prospective 2-year radiostereometric analysis with 5-years clinical follow-up.

BACKGROUND: The osseointegrated (OI) prosthesis is a treatment option for transfemoral amputees with a short residual femur and/or difficulties caused by using the prosthetic socket. Implant removal due to aseptic or septic loosening is not uncommon, but the association between implant migration patterns and the need for removal has not previously been studied. We conducted a prospective model-based radiostereometric analysis study to investigate: if the OI implant migration pattern 1) differs between later removed implants and non-removed implants, (2) predicts later implant removal, and (3) if the precision of the method is acceptable. HYPOTHESIS: Model-based radiostereometric analysis of the OI implant migration pattern can be used to predict later OI implant removal. MATERIAL AND METHODS: A prospective cohort of 17 consecutive transfemoral amputees suitable for surgery (11 males), mean age 50 (range 32-66) were treated with an OI implant (Integrum AB, Sweden). Postoperative stereoradiographs of the OI implant were obtained during 24-month follow-up. X, Y, and Z translations and total translations were evaluated using CAD-implant models. Implant survival was followed for up to 60 months. RESULTS: Six total implant removals (fixture and abutment) and four partial removals (abutment) were conducted (10/17 (59%)), and one patient did not use the OI implant. The removed implants group migrated a mean (±standard deviation) 0.55mm±0.75mm (p=0.009) and the non-removed implants group migrated 0.31mm±0.51mm (p=0.22) in total translations from 3 months to last follow-up. Odds ratio for implant removal was 22.5 (95% CI: 1.6 to 314 (p=0.021)) if the OI implants migrated distally. CONCLUSION: Later removed OI implants migrated from 3 months to last follow-up and more than the non-removed OI implants. Distal implant migration greatly increased the odds of implant removal. Ten out of 17 OI implants were removed within 5 years of follow-up. We advise to use OI implants with caution and close follow-up in consideration of the risk of complications. LEVEL OF EVIDENCE: IV, Prospective study.

[Blind corticosteroid injection as primary treatment of trigger finger].

Trigger finger (TF) is a common condition with a lifetime prevalence up to 2%. Local corticosteroid injection at the level of the A1 pulley is a frequently used and safe treatment for TF with cure rates around 50% in randomised controlled trials, while surgical release has cure rates near 100% but more severe complications. Blind local corticosteroid injection has the same effect as ultrasound-guided local corticosteroid injection on cure rates, and the effect remains the same, whether the steroid is placed intra-sheath or extra-sheath. The treatment of TF can be carried out as blind local corticosteroid injection in general practice before possible referral to an orthopaedic specialist.

Bone Mineral Density Measurements Around Osseointegrated Implants: A Precision Study and Validation of Scan Protocol for Transfemoral Amputees.

Visual evaluation of bone changes around an osseointegration (OI) implant in femoral amputees examined on plain radiographs shows that periprosthetic bone resorption takes place during the first years after OI surgery, but the bone mineral density (BMD) change has not been previously quantified by dual-energy X-ray absorptiometry (DXA). Precision is vital when monitoring BMD changes around implants, and thus the aim of this study was to evaluate the precision and feasibility of a scan protocol for BMD measurements in proximity of OI implants. The proximal part of 2 human cadaveric femoral bones (specimens A and B) with OI implants were mounted in a positioning jig and DXA scans were repeated 5 times in increments of 5° from neutral (0°) to 20° flexion and rotation. BMD changes as a result of change in leg position were evaluated. Repeated patient examinations (n = 20) were conducted in a clinical setting and the precision error was calculated for each of 7 periprosthetic custom-made regions of interest (ROIs). The precision of cadaveric BMD measurements in neutral position was <3.3%. Even 5° flexion or rotation in femur position caused significant changes in average BMD (p <0.04). Depending on ROI, the percentage of coefficient of variation (%CV) and average BMD was <6% at 10° flexion and rotation. At 20° flexion, %CV increased up to 12.7% and average BMD increased up to 9.9%. The clinical short-term precision root mean square standard deviation ranged from 0.031 g/cm2 to 0.047 g/cm2 and %CV ranged from 3.12% to 6.57% depending on ROI. Simulated hip flexion or rotation of the femur affected periprosthetic BMD measurements around OI implants in cadaveric femoral bones, which stresses the importance of a reproducible set-up during DXA scans to reduce measurement errors caused by variation in leg position. Adherence to the scan protocol with a relaxed position of the residual limb resulted in an acceptable short-term precision below 6.6%.

[Denosumab may be a supplement to the surgical treatment of giant cell tumours of bone].

Giant cell tumour of bone (GCTB) is an aggressive bone tumour causing bone destruction. GCTB requires surgical treatment, and severe cases have a high risk of functional morbidity. GCTB consists of receptor activator of nuclear factor kappa-B (RANK)-positive osteoclast-like giant cells. The formation and activity of these cells are mediated by the interaction with RANK ligand (RANKL) released from neoplastic stromal cells. Denosumab is a human monoclonal antibody which inhibits RANKL and impairs the growth of the GCTB. Several studies have described the ability of denosumab to downgrade the extent of surgical treatment and improve the functional outcome.