A Child with a Painful Foot: How to Get a Definitive Diagnosis.

This case report describes an 8-year-old healthy boy with a retained wooden foreign body in his 4th metatarsal bone of his right foot. He was presented several months after the initial trauma, stepping into a toothpick, had occurred. He was operated in our hospital, and the wooden toothpick was removed. The operation and recovery were both uncomplicated. History and physical examination are essential in these types of cases with a history of penetrating trauma but can be inconclusive due to the delay in presentation. Aggressive treatment on the other hand is necessary to prevent bigger problems such as the development of inflammatory problems and persisting complaints. A thorough, systematic, and complete work-up from the history to treatment is therefore necessary and will be described in this case report.

Ceramic-on-ceramic articulation in press-fit total hip arthroplasty as a potential reason for early failure, what about the survivors: a ten year follow-up.

PURPOSE: In press-fit total hip arthroplasty (THA), primary stability is needed to avoid micromotion and hereby aseptic loosening, the main reason for early revision. High aseptic loosening revision rates of the seleXys TH+ cup (Mathys Medical) with Ceramys ceramic-on-ceramic (CoC) bearing are seen in literature. Since CoC is presumed to overcome long-term wear-related revisions, the reason for early failure of this cup is important to clarify. The aim is to investigate its ten year outcomes and differentiate between potential causes and identify risk factors for aseptic loosening. METHODS: Retrospective screening of a prospectively documented series of 315 THAs was performed. Primary outcome was cumulative incidence of cup revision due to aseptic loosening. Secondary outcomes were component revision and reoperation. Additionally, potential predictive factors for aseptic loosening were evaluated. RESULTS: At the median follow-up of 9.7 years [IQR 4.4; 10.3], 48 TH+ (15.2%) were revised due to aseptic loosening. Competing risk analysis showed a ten year cumulative incidence of cup revision due to aseptic loosening of 15.6% (95% CI 12.0-20.2). Stabilization of early revision rates was observed, following a high rate of respectively 81.3% (n = 39) and 95.8% (n = 46) within the first two and three years. No significant predictive factors for aseptic loosening were found. CONCLUSION: The ten year results of seleXys TH+ cup with Ceramys CoC bearing showed an unacceptable high aseptic loosening rate, which stabilized over time after a high early failure incidence. This could be attributed to a problem with osseointegration during the transition of primary to definitive stability.

Two-year clinical results of a novel load redistribution device for the treatment of medial knee OA.

PURPOSE: A potential method to relieve the pain from medial osteoarthritis of the knee is to offload the medial compartment. The Latella™ Knee Implant is a novel device designed to offload the medial compartment. The objective of the Cotera-1 study was to evaluate the preliminary safety and feasibility of the Latella implant to treat patients with medial OA of the knee, by a 2-year follow-up of a prospective multicenter feasibility study (Cotera-1) performed in the Netherlands and UK METHODS: In this first-in-man study, 11 participants received the Latella implant and were followed for 2 years, documenting physician assessment, Patient-Reported Outcome (PRO) scoring (KOOS, IKDC, Kujala, SF-36); Patient Global Assessment (PGA), radiographic analysis and MRI analysis, complications, reoperation rate and hip-knee-ankle axis. RESULTS: The Latella Knee Implant system proved to be well tolerated and demonstrated a low-risk safety profile up to 24 months post-treatment. A responder analysis was performed of the subjects who still had the Latella implanted at 24-month time point (n = 9). Based on a MCID of eight for KOOS pain sub-scale, 78% of the subjects at the 24 month time point would be considered as responders. Similarly, based on improvement in the medial knee pain compared to baseline using the NRS scale of 1-10, 89% of the subjects at the 24-month time point would be considered as responders. Two patients were revised during follow-up: one for arthrofibrosis and one converted to TKA for progression of OA. CONCLUSIONS: The early clinical experience with the Latella Knee Implant in this pilot feasibility study has been encouraging. It appears to be a safe implant with possible effect on medial OA. Additional studies need to be performed to assess the safety and efficacy of the procedure in a larger patient population. LEVEL OF EVIDENCE: II.

Treatment of an osteoporotic vertebral compression fracture with the StaXx FX system resulting in intrathoracic wafers: a serious complication.

PURPOSE: To report a serious complication of the StaXx FX system used to stabilize an osteoporotic vertebral fracture. CASE REPORT: A 76-year-old woman presented with a painful vertebral fracture. Treatment by means of a PEEK wafer kyphoplasty was complicated by malposition of the wafers. The patient recovered fully after removal of the wafers by means of a thoracotomy. CONCLUSIONS: New treatment modalities have their own pitfalls and possible complications, as demonstrated in this case report. Caution regarding implementation of new treatment modalities should be practiced.

Acute compartment syndrome of the thigh following total knee arthroplasty.

A 62year old man developed a compartment syndrome of the thigh after total knee arthroplasty. Twelve years previously he had a HTO of the same knee complicated by a compartment syndrome of the calf. The clinical diagnosis was confirmed with intracompartmental pressure measurement. Following fasciotomy pressures were normalized and further course was uncomplicated. Compartment syndrome of the thigh is a rare, but potentially devastating, complication following total knee arthroplasty. A previous compartment syndrome of the calf is identified as a risk factor.

A randomised controlled trial for the effectiveness of intra-articular Ropivacaine and Bupivacaine on pain after knee arthroscopy: the DUPRA (DUtch Pain Relief after Arthroscopy)-trial.

PURPOSE: In this double-blinded, randomised clinical trial, the aim was to compare the analgesic effects of low doses of intra-articular Bupivacaine and Ropivacaine against placebo after knee arthroscopy performed under general anaesthesia. METHODS: A total of 282 patients were randomised to 10 cc NaCl 0.9%, 10 cc Bupivacaine 0.5% or 10 cc Ropivacaine 0.75%. Patients received the assigned therapy by intra-articular injection after closure of the portal. Pain and satisfaction were measured at one, 4 h and 5-7 days after arthroscopy with Numerical Rating Scale (NRS) -scores. NSAID consumption was also recorded. RESULTS: One-h NRS-scores at rest were higher in the NaCl group compared with the Bupivacaine group (P < 0.01), 1 h NRS-scores in flexion were higher in the NaCl group compared with the Bupivacaine (P < 0.01) and Ropivacaine (P < 0.01) groups. NRS-satisfaction at 4 h was higher for the Bupivacaine group compared with the NaCl group (P = 0.01). Differences in NRS-scores were significant but low in magnitude. NSAID consumption was lower in the Bupivacaine group compared with the NaCl group (P < 0.01). CONCLUSIONS: The results of this randomised clinical trial demonstrate improved analgesia after administration of low doses of intra-articular Bupivacaine and Ropivacaine after arthroscopy of the knee. Considering reports of Bupivacaine and Ropivacaine being chondrotoxic agents and the relatively small improvement on patient comfort found in this trial, it is advised to use systemic anaesthetic instead of intra-articular Bupivacaine or Ropivacaine for pain relief after knee arthroscopy.

Total hip replacement with a superolateral bone graft for osteoarthritis secondary to dysplasia: a long-term follow-up.

We evaluated the long-term results of 116 total hip replacements with a superolateral shelfplasty in 102 patients with osteoarthritis secondary to developmental dysplasia of the hip. After a mean follow-up of 19.5 years (11.5 to 26.0), 14 acetabular components (12%) had been revised. The cumulative survival at 20 years was 78%, with revision for loosening of the acetabular component as the end-point. All grafts were well integrated and showed remodelling. In six grafts some resorption had occurred under the heads of the screws where the graft was not supporting the socket. Apart from these 14 revisions, seven acetabular components had possible radiological signs of loosening at a mean follow-up of 14.5 years, one had signs of probable loosening, and five had signs of definite loosening. These results indicate that this technique of bone grafting for acetabular reconstruction in hip dysplasia is a durable solution for cemented acetabular components.

Effects of mechanical compression of a fibrous tissue interface on bone with or without high-density polyethylene particles in a rabbit model of prosthetic loosening.

BACKGROUND: The mechanisms leading to aseptic loosening of a total hip replacement are not fully understood. A fibrous tissue interface can be present around the implant. Hypothetically, component micromovements can compress this interface and cause increased fluid pressure according to biphasic models. We tested the hypothesis that compression of a fibrous membrane with or without the presence of high-density polyethylene particles leads to bone degradation. METHODS: A titanium implant was inserted in forty-five rabbit tibiae, and, after osseous integration was achieved, a fibrous tissue interface was generated. The animals were randomized to undergo a sham operation, treatment with compression of the fibrous membrane, treatment with high-density polyethylene particles, or treatment with both compression and particles. Morphometric analysis of the surrounding bone was performed on cryostat sections after Giemsa staining and staining of tartrate-resistant acid phosphatase activity. RESULTS: Forty specimens were available for analysis; five tibiae with an infection were excluded. After nine weeks, the controls showed vital bone, whereas the specimens treated with compression showed necrosis of bone and replacement of bone by cartilage in a discontinuous layer (p < 0.05 for both) but not fibrous tissue. Treatment with high-density polyethylene particles caused replacement of bone by fibrous tissue (p < 0.05) but not necrosis or cartilage formation. Compression combined with the presence of high-density polyethylene particles caused bone necrosis and loss of bone with replacement by cartilage and fibrous tissue (p < 0.05). CONCLUSIONS: In this in vivo study in rabbits, fibrous membrane compression led to bone necrosis and cartilage formation, possibly because of fluid pressure or fluid flow, whereas the presence of high-density polyethylene particles led to the loss of bone with replacement of bone by fibrous tissue. Cartilage formation may be a protective response to fluid pressure and/or fluid flow. Fibrous membrane compression may play an important role in the early stages of loosening of a total hip replacement.

Weber rotation total hip replacement: a prospective 5- to 20-year followup study.

Between 1974 and 1989, 315 primary total hip replacements (274 patients) were done using the cemented Weber Rotation prosthesis and standardized operative technique, which was modified for the stem in 1978. After the first postoperative year, all patients had routine clinical and radiologic examinations at 2-year intervals. Twenty-one patients (22 hips) were lost to followup. At the most recent followup, 30 of 293 hips (253 patients) had been revised: 24 hips for aseptic loosening, five hips for infection, and one hip for a femoral fracture. Survivorship analyses with revision for aseptic loosening as an end point for the 315 hips showed 93% and 78% survival after 10 and 15 years, respectively. Separate survival analyses for the socket showed 99% and 89% survival after 10 and 15 years, respectively. The stem had a survival of 94% and 81%, respectively, during the same time. Survival at 15 years with radiologic evidence of loosening as an end point was 85% for the socket and 72% for the stem. The cementing technique and the design of the acetabular component significantly influenced the rate of loosening. Survivorship analyses with revision for aseptic loosening of the socket, using a modified second generation cementing technique and a hemispheric socket, showed 100% survival after 10 years and 98% after 13 years.

Trochanteric reduction osteotomy as a treatment for refractory trochanteric bursitis.

We describe a new operative procedure for patients with chronic trochanteric bursitis. Between March 1994 and May 2000, a trochanteric reduction osteotomy was performed on ten patients (12 hips). All had received conservative treatment for at least one year. Previous surgical treatment with a longitudinal release of the iliotibial band combined with excision of the trochanteric bursa had been performed on five hips. None had responded to these treatments. The mean follow-up was 23.5 months (6 to 77). The mean Merle d'Aubigné and Postel score improved from 15.8 (8 to 20) before to 27.5 (18 to 30) after operation, six patients showing very great improvement, five great improvement and one fair improvement. We conclude that trochanteric reduction osteotomy is a safe and effective procedure for patients with refractory trochanteric bursitis who do not respond to conservative treatment.

Mechanical compression of a fibrous membrane surrounding bone causes bone resorption.

Early micromovement and migration of a prosthesis of a hip or knee predicts late clinical loosening of the prosthesis. Such migration is likely to be associated with mechanical compression of the fibrous membrane interpositioned between bone and prosthesis during movement. Compression of the fibrous membrane by loading may lead to locally high fluid pressures reaching the underlying bone tissue. It has been established that high fluid pressures can lead to bone resorption. This resorption may eventually lead to clinical loosening of the prosthesis. We developed an experimental model to study the effects of compression of a soft tissue layer located between a titanium implant and cortical bone. In twelve rabbits, this device was implanted in the proximal tibia and allowed to osseointegrate. Next, a layer of soft tissue was allowed to form between titanium and bone. Subsequently, in six rabbits a cyclic load of 60 times in 2 min per day during 2 weeks was applied, leading to compression of the interpositioned soft tissue layer only. In the other six rabbits no load was applied. In all six loaded specimens, osteocyte death and bone resorption was observed underneath the area where compression of the fibrous membrane was exerted to a depth exceeding the amplitude of the loading device. Furthermore, formation of fibrocartilage was observed in the loaded areas. Formation of fibrocartilage, osteocyte death or bone resorption did not occur in the controls. Our results indicate that compression of a fibrous membrane surrounding bone can lead to resorption of the underlying bone primarily because of osteocyte death and subsequent resorption of dead bone tissue. This may explain the observation that early migration of a hip or knee prosthesis is predictive of clinical loosening of the prosthesis.

Socket wear in ceramic-on-polyethylene total hip arthroplasties: fixed versus rotating heads.

We measured radiographically the polyethylene socket wear in 34 hip prostheses with a 32 mm Al2O3-ceramic head with a rotating bearing and in 37 prostheses with a "fixed" ceramic head. The mean follow-up was 12 years in both groups. The mean annual linear wear of the polyethylene was 0.034 and 0.069 mm, respectively, (Mann-Whitney U-test p < 0.0001) in the "rotation" and the "fixed" group. A rotating bearing between the head and neck in a modular total hip system seems to reduce socket wear as compared to fixed taper junctions.

Fluid pressure causes bone resorption in a rabbit model of prosthetic loosening.

High fluid pressures can be present throughout the effective joint space after total hip replacement and can extend locally to the bone implant interface. A new experimental implant model was developed to study whether local fluid pressure can induce osteolysis at a bone implant interface. Twelve mature rabbits received a titanium implant that was allowed to osseointegrate before a fluid pressure of 150 mm Hg was applied to a specific area of the titanium bone interface in six of the animals. Osteolysis occurred in all six implants exposed to the fluid pressure. In two of these animals, no measurable flow occurred. In both animals a localized osteolytic lesion developed with evidence of osteocyte death in the surrounding cortical bone. In four animals, fluid flow away from the lesion occurred after several days that corresponded to either the formation of a canal through the cortical bone or extended resorption of the surrounding cortical bone. In some of these specimens, the microscopic appearance was similar to that of prosthetic loosening: high numbers of macrophages were observed containing intracellular bone particles. No resorption was found in any of the six control animals. The authors' results point to the possibility that all features of prosthetic loosening that are ascribed to particle activation can be explained alternatively by effects of fluid pressure.

Benign cellular responses in rats to different wear particles in intra-articular and intramedullary environments.

We examined the cellular responses to various particles injected into the knees and the intramedullary femoral cavities of rats in the presence of polymethylmethacrylate (PMMA) plugs. The intra-articular particles were mainly ingested by synovial fibroblasts. Increased numbers of macrophages were not detected and there was only a slight increase in synovial thickness. Cellular responses in the intramedullary space were similarly mild and bone resorption around the PMMA plug did not occur. Bone formation was inhibited only by polyethylene particles. In contrast to current views, our study shows that wear particles per se do not initiate bone resorption.