Knee function, quality of life, pain, and living conditions after distal femoral resection knee arthroplasty for non-tumor indications.

BACKGROUND: Distal femoral resection knee arthroplasty is a limb salvage procedure. The impact of distal femoral resection arthroplasty on patient function and health status is unknown. The aim of this study was to report knee function, quality of life, knee pain, and living conditions after distal femoral resection knee arthroplasty for non-tumor indications. METHODS: Of 52 patients (52 knees) undergoing distal femoral resection knee arthroplasty in a single institution between 2012 and 2021, 22 were excluded as 3 patients had ≤90 days follow-up, 6 had died, and 13 declined or were unable to participate for unrelated reasons. Thus, 30 patients were included and interviewed by telephone in March 2021 (mean follow-up 3.5 years after surgery). Patient completed the Oxford Knee Score (0-48, 48 best), EQ-5D-5L, and the Copenhagen Knee ROM, and information on pain and living conditions was obtained. RESULTS: The mean age was 67.9 years (SD 13.6), and 21 (70%) were female. Mean total Oxford Knee Score was 29.9 (SD 10.5), mean Copenhagen Knee ROM flexion was 116° (SD 21.6), and mean extension was - 2° (SD10.1). Mobility aids were used by 18 (60%) patients, i.e. a cane (30%), walker (26.7%) or wheelchair (3.3%). Mean EQ-5Dindex score was 0.70 (SD 0.22) and mean EQ-5D VAS score was 55.4 (SD 23.9). Nine (30%) patients used paracetamol or NSAID and 2 (6.7%) used opioids for knee pain. Mean VAS knee pain score was 1.30 (SD 2.2) at rest and 2.8 (SD 3.1) when walking. Most (90%) patients lived in their own home, with only 3 patients in nursing homes. Two-thirds (66.7%) required no home care, 5 (16.6%) received home care 1-2 times over 2 weeks, and 5 (16.6%) every day. CONCLUSION: Distal femoral resection knee arthroplasty appears to be a viable treatment option for non-tumor indications. Acceptable patient outcomes were achieved in terms of functional status and quality of life, especially considering treatment alternatives such as femoral amputation.

Patient safety in distal femoral resection knee arthroplasty for non-tumor indications: a single-center consecutive cohort study of 45 patients.

BACKGROUND: Distal femoral resection knee arthroplasty may be a viable option for several indications other than bone tumors. Resection knee arthroplasty appears to be becoming more common, but patients requiring this type of surgery are often elderly and with high comorbidity. The aim of this study was to report in-hospital complications, readmissions, reoperations, and mortality after distal femoral resection knee arthroplasty for non-tumor indications. METHODS: We retrospectively identified a consecutive cohort of 45 knees (45 patients) treated with distal femoral resection knee arthroplasty in a single institution between 2012 and 2021. Indications for surgery were failure of osteosynthesis (8), primary fracture treatment (2), periprosthetic fracture (22), and revision arthroplasty with severe bone loss (13). A major reoperation was defined as a major component exchange procedure or amputation. Mean follow-up was 3.9 years. RESULTS: The mean age was 71.3 years (SD 12.3), and 64.4% were female; 8.9% were ASA I, 40% ASA II, and 51% ASA III. Median length of stay was 7 days (range 3-19) with no major in-hospital complications, but 55.6% (n = 25) required blood transfusion. The 90-day readmission rate was 17.8% (n = 8), of which 50% was prosthesis-related. Four patients (8.9%) underwent major reoperation due to infection (n = 2), mechanical failure (n = 1), or periprosthetic fracture (n = 1). The mortality rate was 0% ≤ 90 days and 2.2% ≤1 year. CONCLUSIONS: Distal femoral resection knee arthroplasty in this fragile patient population appears to be a viable and safe option considering that it is a limp salvage procedure most cases.

Local Anesthetic Wound Infiltration after Osteosynthesis of Extracapsular Hip Fracture Does Not Reduce Pain or Opioid Requirements: A Randomized, Placebo-Controlled, Double-Blind Clinical Trial in 49 Patients.

Background and purpose: Local infiltration analgesia (LIA) supports early mobilization after hip and knee arthroplasty. Inspired by this, we studied the effectiveness of wound infiltration with the long acting local anesthetic ropivacaine in an effort to decrease the need for postoperative opioids after osteosynthesis of extracapsular hip fracture. Methods: Forty-nine patients undergoing osteosynthesis with a sliding hip screw were randomized into two groups in a double-blind study (ClinicalTrials.gov:NCT01119209). The patients received intraoperative infiltration followed by 6 postoperative injections through a wound catheter in eight-hour intervals. 23 patients received ropivacaine and 26 received saline. The intervention period was 2 days, and the observation period was 5 days. In both groups, there were no restrictions on the total daily dose of opioids. Pain was assessed at specific postoperative time points, and the daily opioid usage was registered. Results: Intraoperative infiltration with 200 mg ropivacaine and postoperative repeated infiltration with 100 mg ropivacaine did not result in statistically significant difference between the groups regarding postoperative opioid consumption or pain. Interpretation: Ropivacaine as single component in postoperative treatment of pain after hip fracture is not effective. In our setup, wound infiltration with ropivacaine is not statistically significantly better than placebo.

Preoperative Hypoalgesia After Cold Pressor Test and Aerobic Exercise is Associated With Pain Relief 6 Months After Total Knee Replacement.

OBJECTIVES: Chronic pain after total knee replacement (TKR) is not uncommon. Preoperative impaired conditioning pain modulation (CPM) has been used to predict chronic postoperative pain. Interestingly, exercises reduce pain sensitivity in patients with knee osteoarthritis (KOA). This pilot study investigated the association between exercise-induced hypoalgesia (EIH) and CPM on post-TKR pain relief. METHODS: Before and 6 months post-TKR, 14 patients with chronic KOA performed the cold pressor test on the nonaffected leg and 2 exercise conditions (bicycling and isometric knee extension), randomized and counterbalanced. Before and during the cold pressor test and after exercises test stimuli were applied to extract the pain sensitivity difference: computer-controlled cuff inflation on the affected lower leg until the participants detected the cuff pain threshold (cPPT) and subsequently the cuff pain tolerance (cPTT) and manual pressure pain thresholds (PPTs) at the legs, arm, and shoulder. Clinical pain intensity (numerical rating scale [NRS]) and psychological distress (questionnaires) were assessed. RESULTS: Clinical pain intensity, psychological distress, cPPT, and PPT at the affected leg improved post-TKR compared with pre-TKR (P<0.05). Preoperatively, the CPM and bicycling EIH assessed by the increase in cPTT correlated with reduction in NRS pain scores post-TKR (P<0.05). Improved CPM and EIH responses after TKR were significantly correlated with reduction in NRS pain scores post-TKR (P<0.05). DISCUSSION: In KOA patients, hypoalgesia after cold pressor stimulation and aerobic exercise assessed preoperatively by cuff algometry was associated with pain relief 6 months after TKR. EIH as a novel preoperative screening tool should be further investigated in larger studies.

Iodine-impregnated incision drape and bacterial recolonization in simulated total knee arthroplasty.

Background and purpose - Iodine-impregnated incision drapes (IIIDs) are used to prevent surgical site infection (SSI). However, there is some evidence to suggest a potential increase in SSI risk as a result of IIID use, possibly from promotion of skin recolonization. A greater number of viable bacteria in the surgical field of an arthroplasty, and surgery in general, may increase the infection risk. We investigated whether IIID use increases bacterial recolonization compared to no drape use under conditions of simulated total knee arthroplasty (TKA). Methods - 20 patients scheduled for TKA were recruited. Each patient had 1 knee randomized for draping with IIID, while the contralateral knee was left bare. The patients thus served as their own control. The operating room conditions and perioperative procedures of a TKA were simulated. Cylinder samples were collected from the skin of each knee prior to disinfection, and again on 2 occasions after skin preparation-75 min apart. Quantities of bacteria were estimated using a spread plate technique under aerobic conditions. Results - We found similar quantities of bacteria on the intervention and control knees immediately after skin disinfection and after 75 min of simulated surgery. These quantities had not increased at the end of surgery when compared to baseline, so no recolonization was detected on the draped knees or on the bare knees. Interpretation - The use of IIIDs did not increase bacterial recolonization in simulated TKA. This study does not support the hypothesis that IIIDs promote bacterial recolonization and postoperative infection risk.

The efficacy of tourniquet assisted total knee arthroplasty on patient-reported and performance-based physical function: a randomized controlled trial protocol.

BACKGROUND: Surgical treatment of osteoarthritis with total knee arthroplasty (TKA) usually takes place in a complete bloodless field using a tourniquet. However, doing the surgery without a tourniquet may reduce muscle damage, post-surgery pain and led to improved functional rehabilitation and mobilization. METHODS/DESIGN: A prospective, blinded, parallel-group, controlled superiority trial, with balanced randomization [1:1]. Patients aged 50 or older eligible for primary TKA for osteoarthritis will be consecutively recruited from Department of Orthopedic Surgery and Traumatology, Odense University Hospital, Denmark. A total of 80 patients will be randomly allocated to TKA with or without tourniquet application providing 40 patients for each of the two treatment arms. The tourniquet assisted TKA group will have an automatic, micro-processor-based pneumatic tourniquet inflated around the thigh during surgery. The non-tourniquet assisted TKA group will have surgery performed without application of a tourniquet. The primary aim is to compare tourniquet assisted to non-tourniquet assisted TKA on patient-reported physical function (KOOS-ADL). The secondary aim is to compare post-surgery pain, function in sports and recreation, quality of life, and performance-based physical function. The explorative outcomes include; use of pain medication, single-fiber muscle damage, and changes in mechanical muscle function. The primary endpoint will be at 3-months following surgical treatment, and the time-point for analysis of the primary outcome. However, follow-up will continue up to 1 year, and provide medium-term results. The treatment effect (difference in KOOS-ADL) will be analyzed using a random effects regression model, crude and adjusted results will be reported, if needed. Analyses will be based on the intention-to-treat (ITT). Subsequent per-protocol analysis may be necessary in the event of a substantial number of patients (> 15%) being lost during follow-up. The number needed to treat (NNT) for a positive effect of treatment (>10 points on KOOS-ADL) will be reported. DISCUSSION: This is the first randomized clinical trial comparing the efficacy of tourniquet assisted TKA on patient-reported physical function supported by a range of performance-based secondary outcome measures. As such it will provide high quality evidence that may help determine whether tourniquet should be used in future TKA procedures in patients with osteoarthritis of the knee. TRIAL REGISTRATION: ClinicalTrials NCT01891266.

Local anaesthetic wound infiltration after internal fixation of femoral neck fractures: a randomized, double-blind clinical trial in 33 patients.

Pain control may assist early mobilisation after internal fixation of femoral neck fractures. Systemic opioids have significant side effects in elderly patients. We present an evaluation of the effect of local anaesthetic infiltration in such cases , the objective being to decrease the need for postoperative opioids and to improve pain control for patients after surgery. 33 patients undergoing internal fixation with 2 parallel hook pins were randomized into 2 groups in a double blind study (ClinicalTrials.gov: NCT00529425). 33 patients received intraoperative infiltration followed by 6 postoperative injections through an intraarticular catheter in eight-hour intervals. 19 patients received ropivacaine and 14 received saline. The intervention period was 48 hours and the observation period was 5 days. In both groups there were no restrictions on the total daily dose of rescue analgesics. Pain was assessed at specific postoperative time-points and the daily consumption of opioid drugs needed for analgesia was registered. There was no significantly reduced consumption of standardized opioid rescue analgesics or pain in the study group receiving ropivacaine injections. Apart from a reduction in nausea in the study group on the second postoperative day, there were no significant differences in the occurrence of side effects between the groups. On day 2 the placebo group had less pain than the study group. Local anaesthetic infiltration after fixation of femoral neck fractures does not reduce opioid consumption or pain'.

Microdialysis in the femoral head of the minipig and in a blood cloth of human blood.

INTRODUCTION: Microdialysis can detect ischemia in soft tissue. In a previous study, we have shown the development of ischemia in the femoral head removed from patients undergoing total hip replacement. That study also raised some methodological questions that this study tries to answer: what is happening in the dead space around the catheter in the drill canal, and is there an equilibrium period after the insertion of the catheter? MATERIAL AND METHODS: In an ex-vivo study using 5 syringes with 5 mL human blood, a microdialysis catheter was inserted and microdialysis was performed over 3 h. In an in-vivo study, a drill hole was made in the proximal part of the femur in 6 mature Göttingen minipigs and microdialysis was performed over 3 h. The pigs were kept normoventilated during the experiment. RESULTS: The ex-vivo microdialysis results showed that lactate kept a steady level and glucose and glycerol both fell; pyruvate fell but leveled out. The mean lactate/pyruvate ratio increased from 13 (SD 4) to 32 (SD 6) (p < 0.001). In vivo, relative recovery was 57% (SD 11). Lactate increased, pyruvate stayed constant, and glucose and glycerol levels fell. The lactate/pyruvate ratio increased from 30 (8) initially to 37 (8) after 1 h (p = 0.007) but no statistically significant change from 1 to 2 h was observed. INTERPRETATION: The ex-vivo study showed a clear washout pattern, and was different from what we see in bone. The in-vivo study indicated that an equilibrium period is necessary or that a reference measurement in healthy bone must be used when performing short measurements in bone.

Extension block pinning of mallet fractures.

The operative treatment of mallet fractures of more than one third of the articular surface is controversial. The purpose of this study was to evaluate the complications and functional outcome of extension block pinning technique. Thirty-six consecutive patients with mallet fractures that involved more than one third of the joint surface were treated by extension block pinning a median of 3 days after injury (range 0-35, mean 7). Clinical outcome was graded according to Crawford's criteria. At a median follow-up of 16.5 months (range 2.5-52, mean 20) 23 patients had an excellent or good result, 11 patients had a fair, and 2 patients a poor, clinical outcome according to Crawford's criteria. None of the patients complained of pain. The median extension loss was 0 degrees (range 0-20, mean 4) and the median flexion was 70 degrees (range 30-95, mean 68). Eight patients had operative or direct postoperative complications including superficial infection (n = 6), loss of Kirschner wire (K-wire) fixation (n = 1), and K-wire mal position (n = 1). The extension block pinning technique is a minimally invasive method of treating mallet fractures with low morbidity and a good functional outcome.

Revision total hip arthroplasty using a modular tapered stem with distal fixation: good short-term results in 125 revisions.

After 2 to 7 years we reviewed 125 prosthetic hip arthroplasty stem revisions using a modular tapered stem with distal fixation. Median age of these patients was 68 (33-92) years. Baseline and follow-up data were registered prospectively according to the Danish Hip Arthroplasty Registry. Survival, free of any rerevision, was 94%. Harris Hip Score improved from average 44 to 85. Bony regeneration was an early and significant finding in most cases. Complications included 4 (3%) fractures intraoperatively and 8 (6%) dislocations, 4 (3%) deep infections, and 1 (1%) stem fracture. This modular taper system is very versatile, can be used in most femoral revision cases, and allows rapid bone remodeling. We did not find an increased number of complications compared to the literature. Further long-term follow-up, however, is essential.

Blood flow and microdialysis in the human femoral head.

BACKGROUND: If it would be possible to detect lack of flow and/or the development of ischemia in bone, we might have a way of predicting whether a broken bone will heal. We established microdialysis (MD) and laser Doppler (LD) flow measurement in the human femoral head in order to be able to detect ischemia and measure changes in blood flow. MATERIAL AND METHODS: In 9 patients undergoing total hip arthroplasty for primary osteoarthrosis, two MD catheters were inserted into the femoral head through two drill holes after the blood flow had been visualized by LD. Then primary samples were collected with the femoral head in situ; thereafter, the head was removed and samples were collected over the following 4 hours ex vivo. The variables obtained by MD were concentrations of glucose, lactate, pyruvate, and glycerol in extracellular fluid. RESULTS: The results showed development of ischemia with a statistically significant decrease in glucose concentration and elevation of the lactate/pyruvate ratio over time. The LD showed flow with the femoral head in situ and lack of flow when the femoral head was removed. INTERPRETATION: The use of MD was established in the human femoral head. Ischemic levels were detected within 2 h of cessation of blood flow in most patients.