Computed tomography for managing periprosthetic femoral fractures. A retrospective analysis.

BACKGROUND: Periprosthetic fractures (PPF) present a common cause for revision surgery after arthroplasty. The choice of performing either an osteosynthesis or revision arthroplasty depends on the orthopedic implant anchored and loosening. Standard diagnostics include x-ray imaging. CT is usually performed to confirm implant loosening in case of ambiguous diagnosis on standard x-ray imaging. This study aimed to examine the role of CT as a diagnostic modality and its implications for treatment planning and outcome. METHODS: Patients treated for PPF from January 2010 to February 2018 were included. X-ray and CT reports were analyzed to assess implant loosening. The planning for surgery and the final surgical treatment were evaluated. In addition, patient characteristics were analyzed and compared between patients with and without additional CT as a preoperative diagnostic procedure. RESULTS: Seventy-five patients were eligible for the study. X-ray imaging was performed in 90.7% of cases. CT was performed in 60% of the cases as part of the preoperative diagnostic. A clear statement on implant stability or loosening could not be made in 69.1% after X-ray imaging and in 84.4% following CT imaging. Revision arthroplasty for loosened femoral prosthesis components was necessary in 40% of cases. No difference could be determined comparing patients with X-ray imaging to those with X-ray and additional CT. In both groups, operative treatment did not deviate from the preoperative planning. DISCUSSION: In two thirds of the conventional radiographic findings, no reliable evaluation of implant loosening was possible in femoral PPFs. Intriguingly, additional CT did not improve the evaluation of implant loosening. Nonetheless, CT scans are often performed if loosening assessment is unclear on regular radiographs. This fact can explain the bias CT results in comparison to regular radiography. However, software-supported CT diagnosis could help to adequately answer the question of loosened implants in PPF in the near future. Since the diagnosis of fracture and their morphology assessment is currently adequately performed using X-rays, CT shall not be considered as the gold standard.

Radiocarpal fusion and midcarpal resection interposition arthroplasty: long-term results in severely destroyed rheumatoid wrists.

BACKGROUND: The aim of this retrospective study is to evaluate distal resection interposition arthroplasty of the wrist as a tool to restore mobility as well as to restore stability in severely destroyed wrist joints. METHODS: Thirty-four wrists in 28 rheumatoid arthritis patients were included. The mean follow-up time was 9 years after surgical treatment with clinical and radiological examination. The results were accessed based on a modification of Clayton ́s scoring system as well as a functional questionnaire. RESULTS: 71% patients were satisfied with pain, function and activities of daily life. Better results were reported by patients with a young age, early surgical intervention, a shorter duration of the disease, and lesser involvement of other joints. CONCLUSIONS: The results for radiocarpal arthrodesis were comparable to those of synovectomy or arthrodesis of the wrist. The results after total wrist joint arthroplasty varies probably as the result of different patient groups, implant types and evolution of prosthetic designs, and are not comparable with the present study.

Creatine Supplementation Supports the Rehabilitation of Adolescent Fin Swimmers in Tendon Overuse Injury Cases.

Our purpose was to investigate the effect of creatine (Cr) supplementation on regeneration periods in tendon overuse injury rehabilitation of adolescent fin swimmers. The participants of this study were injured adolescent competitive fin swimmers (n = 18). The subjects were randomly assigned the creatine (CR) or placebo (PL) groups with a double-blind research design. The subjects were given Cr supplementation or received the placebo as part of the conservative treatment of the tendinopathy. We measured the segmental lean mass (SLM;kg), the ankle plantar flexion peak torque (PFT;N·m), the pain intensity (NRS;values), prior to immobilization, after immobilization (R2) and after the 2nd (R4) and 4th (R6) weeks of the rehabilitation period of the injured limb. The creatine kinase (CK; U/L) enzyme levels were measured before immobilization, and then every 24 hours for four days. There was a significant decrease in SLM (CR by 5.6% vs. PL by 8.9%; p < 0.03) after two weeks of immobilization in both groups (p < 0.001). After four weeks rehabilitation the SLM significantly increased in both groups (CR by 5.5% vs. PL by 3.8%; p < 0.01). The percent changes in PFT after supplementation in R4 (p < 0.001) and R6 (p < 0.03) were significantly different between groups. There was a significant percent increase measured in the CR group (R4 by 10.4%; p < 0.001; R6 by 16.8%; p < 0.001), whereas significant, but lower growth found in the PL group also took place (R4 by 7.1%; p < 0.001; R6 by 14.7%; p < 0.001) after four weeks of rehabilitation. Significantly faster decrease were found in NRS of CR versus PL group during treatment (p < 0.02). We detected significantly lower CK levels increase at the CR group compared to the PL group. The results of this study indicate that Cr supplementation combined with therapeutic strategy effectively supports the rehabilitation of tendon overuse injury of adolescent fin swimmers.

Bone matrix, cellularity, and structural changes in a rat model with high-turnover osteoporosis induced by combined ovariectomy and a multiple-deficient diet.

In estrogen-deficient, postmenopausal women, vitamin D and calcium deficiency increase osteoporotic fracture risk. Therefore, a new rat model of combined ovariectomy and multiple-deficient diet was established to mimic human postmenopausal osteoporotic conditions under nutrient deficiency. Sprague-Dawley rats were untreated (control), laparatomized (sham), or ovariectomized and received a deficient diet (OVX-Diet). Multiple analyses involving structure (micro-computed tomography and biomechanics), cellularity (osteoblasts and osteoclasts), bone matrix (mRNA expression and IHC), and mineralization were investigated for a detailed characterization of osteoporosis. The study involved long-term observation up to 14 months (M14) after laparotomy or after OVX-Diet, with intermediate time points at M3 and M12. OVX-Diet rats showed enhanced osteoblastogenesis and osteoclastogenesis. Bone matrix markers (biglycan, COL1A1, tenascin C, and fibronectin) and low-density lipoprotein-5 (bone mass marker) were down-regulated at M12 in OVX-Diet rats. However, up-regulation of matrix markers and existence of unmineralized osteoid were seen at M3 and M14. Osteoclast markers (matrix metallopeptidase 9 and cathepsin K) were up-regulated at M14. Micro-computed tomography and biomechanics confirmed bone fragility of OVX-Diet rats, and quantitative RT-PCR revealed a higher turnover rate in the humerus than in lumbar vertebrae, suggesting enhanced bone formation and resorption in OVX-Diet rats. Such bone remodeling caused disturbed bone mineralization and severe bone loss, as reported in patients with high-turnover, postmenopausal osteoporosis. Therefore, this rat model may serve as a suitable tool to evaluate osteoporotic drugs and new biomaterials or fracture implants.

Effects of dendritic core-shell glycoarchitectures on primary mesenchymal stem cells and osteoblasts obtained from different human donors.

The biological impact of novel nano-scaled drug delivery vehicles in highly topical therapies of bone diseases have to be investigated in vitro before starting in vivo trials. Highly desired features for these materials are a good cellular uptake, large transport capacity for drugs and a good bio-compatibility. Essentially the latter has to be addressed as first point on the agenda. We present a study on the biological interaction of maltose-modified poly(ethyleneimine) (PEI-Mal) on primary human mesenchymal stem cell, harvested from reaming debris (rdMSC) and osteoblasts obtained from four different male donors. PEI-Mal-nanoparticles with two different molecular weights of the PEI core (5000 g/mol for PEI-5k-Mal-B and 25,000 g/mol for PEI-25k-Mal-B) have been administered to both cell lines. As well dose as incubation-time dependent effects and interactions have been researched for concentrations between 1 µg/ml to 1 mg/ml and periods of 24 h up to 28 days. Studies conducted by different methods of microscopy as light microscopy, fluorescence microscopy, transmission-electron-microscopy and quantitative assays (LDH and DC-protein) indicate as well a good cellular uptake of the nanoparticles as a particle- and concentration-dependent impact on the cellular macro- and micro-structure of the rdMSC samples. In all experiments PEI-5k-Mal-B exhibits a superior biocompatibility compared to PEI-25k-Mal-B. At higher concentrations PEI-25k-Mal-B is toxic and induces a directly observable mitochondrial damage. The alkaline phosphatase assay (ALP), has been conducted to check on the possible influence of nanoparticles on the differentiation capabilities of rdMSC to osteoblasts. In addition the production of mineralized matrix has been shown by von-Kossa stained samples. No influence of the nanoparticles on the ALP per cell has been detected. Additionally, for all experiments, results are strongly influenced by a large donor-to-donor variability of the four different rdMSC samples. To summarize, while featuring a good cellular uptake, PEI-5k-Mal-B induces only minimal adverse effects and features clearly superior biocompatibility compared to the larger PEI-25k-Mal-B.

Triple fracture during rehabilitation after revision total knee arthroplasty.

PURPOSE: The incidence of periprosthetic fractures after knee-joint implant revisions is increasing in prevalence. We present a method of treatment for a patient who sustained a triple fracture--a periprosthetic femur fracture, a patella fracture, and a tibial shaft fracture. METHODS: The femoral fracture was treated with a specially designed intramedullary nail, the patella fracture with a figure-of-eight suture, and the tibial shaft fracture by a minimal-invasive plate osteosynthesis using a percutaneous plating technique. RESULTS: Osseous consolidation was confirmed, and the patient presented a satisfying range of movement under full-weight-bearing conditions after mobilisation. CONCLUSIONS: Simultaneous multiple periprosthetic fractures are a special challenge, and in situ coupling of the endoprosthesis with a slotted hollow nail presents a valuable option for the treatment. LEVEL OF EVIDENCE: Level V, Expert opinion.

Allogenous bone with collagen for repair of deep osteochondral defects.

BACKGROUND: A scaffold for treatment of deep osteochondral defects should be stable, integrate well, and provide a surface for chondrocytes. To meet these demands, a biphasic scaffold of allogenous sterilized bone with a collagen surface was developed. Integration was tested in the sheep model. MATERIAL AND METHODS: Cartilage chips were taken from the nonweight-bearing area of the left knee of 12 sheep and cultured. After 4 wk a second procedure followed and defects of 9.4-mm diameter at the weight-bearing area of the medial femoral condyle of the right knee were created. The sterilized scaffold was inserted and the cultured autologous chondrocytes were dripped onto the surface. After 6 wk, 3 mo, and 6 mo the animals were sacrificed; the explanted femoral condyles were evaluated macroscopically and using histologic, immunohistochemical, and electronmicroscopic methods. RESULTS: After 6 wk the level of the surface was well preserved, after 3 mo parts of the scaffold were sintered but after 6 mo the surface was continuous. Full integration of the allogenous bone could be observed after 6 mo. The surface of the scaffold after 6 wk consisted of bone, but after 3 mo some chondrocytes and after 6 mo a continuous chondral layer could be detected. CONCLUSIONS: The biphasic scaffold of allogenous bone and collagen proved to be stable and sufficiently integrated in the short- and midterm interval. Whether the chondrocytes on the surface had been derived from implanted chondrocytes or the scaffold with its surface was sufficiently chondroconductive must be answered in further investigations.

Biphasic scaffolds for repair of deep osteochondral defects in a sheep model.

BACKGROUND: To oppose the disadvantages of autologous osteochondral transplantation in the treatment of deep osteochondral defects such as donor site morbidity, size limitation, and insufficient chondral integration, we developed two biphasic scaffolds of either hydroxylapatite/collagen (scaffold A) or allogenous sterilized bone/collagen (scaffold B) and tested their integration in a sheep model. METHODS: We collected chondral biopsies from 12 sheep for the isolation of chondroblasts and cultured them for 4 wk. We created defects at the femoral condyle and implanted either scaffold A or B with chondrocytes or cell free. After 6 wk, animals were euthanized, we explanted the condyles, and evaluated them using histological, immunohistochemical, molecular biological, and histomorphometrical methods. RESULTS: Specimens with scaffold A showed severe lowering of the surface, and the defect size was larger than for scaffold B. We found more immune-competent cells around scaffold A. Chondrocytes were scarcely detected on the surface of both scaffolds. Histomorphometry of the interface between scaffold and recipient showed no significant difference regarding tissue of chondral, osseous, fibrous or implant origin or tartrate-resistant acid phosphatase-positive cells. Real-time reverse transcriptase-polymerase chain reaction analysis revealed significant up-regulation for collagen II and SOX-9 messenger ribonucleic acid expression on the surface of scaffold B compared with scaffold A. CONCLUSIONS: Scaffold B proved to be stable and sufficiently integrated in the short term compared with scaffold A. More extensive evaluations with scaffold B appear to be expedient.

Association of clinical parameters of operatively treated thoracolumbar fractures with quality of life parameters.

PURPOSE: The intention of the current work was to assess the association between clinical parameters and seven different quality of life (QoL) instruments after surgical treatment of thoracolumbar spinal fractures after an average follow-up of 4.2 years. METHODS: The following human-related quality of life and PRO measures of 66 patients were correlated to clinical parameters such as fingertip-to-floor distance (FFD), Schober measurement, pressure and percussion pain in the lumbopelvine area (PPP), and paravertebral muscle tension: reALOS, SF-36, VAS, VAS spine score, BDI, the GBB-24, and the IES-R. RESULTS: Overall, there was a significant association between the clinical parameters of the thoracolumbar spine such as PPP, paravertebral muscle tension, FFD and Schober's sign on one side, and the seven tested instruments on the other side. CONCLUSIONS: PPP and FFD as well as a small Schober measurement are clinical parameters which significantly influence QoL after surgical treatment of thoracolumbar fractures.

Pyrocarbon spacer as a trapezium replacement for arthritis of the trapeziometacarpal joint; a follow-up study of 60 cases.

Rhizarthrosis is the most common degenerative joint disease of the hand, affecting about 10% of the population. We report our results with trapezium replacement using a pyrocarbon spacer. Between January 2005 and April 2010, 70 patients underwent trapeziectomy with interposition of a pyrocarbon spacer. Sixty patients were examined at an average follow-up of 23.6 (5-64) months after the operation. Six (8.6%) of the 70 implanted pyrocarbon spacers dislocated. Based on the assessment scale devised by Buck-Gramcko, 19 patients achieved a very good outcome (31.6%), 31 patients (51.6%) had a good outcome, six results were satisfactory (10%) and four patients (6.6%) had a poor result. In this study, trapeziectomy and implantation of a pyrocarbon spacer achieved good or very good results in 83.2% of cases. The high cost of the implant and the observed rate of spacer dislocation should however be considered critically. While the short-term results of this method are encouraging, long-term outcomes will show whether this technique can keep up with the good results of suspension arthroplasty.

Follow up of complete subtalar release for clubfoot--Evolution of different scores.

BACKGROUND: Even today there are still some cases of clubfoot that require a more extensive form of treatment. Thus, it is still essential to ascertain the development of the clubfoot after extensive release operations. METHOD: 70 children presenting 99 cases of primary clubfoot (age 8 months-10 years) were followed up after 4.5 and 9 years following complete subtalar release. Function, clinical and radiological results as well as 3 scores were assessed at both dates. RESULTS: Function and pain worsened between the two follow-up periods, whereas objective clinical and radiological results remained equivalent. 44-79% were rated good or excellent depending on the scoring system applied.Older children with primary clubfoot had comparable results to children operated on at a younger age; also pre-operated feet achieved similar results. CONCLUSION: In our opinion the results justify keeping complete release in mind as an alternative method in cases of severe residual and recurrent clubfoot.

Treatment of hand and finger fractures with the Stryker Hand Plating System.

Objectives: 10% of all fractures occur in the fingers and metacarpal region. Early mobilization with preservation of grip function is the goal of any therapy for these injuries. Osteosyntheses with plates are used in complex fractures that do not allow any other treatment. The aim of this retrospective study was to evaluate the performance and safety of the Stryker Hand System. Patients and methods: Between 2010 and 2019, 190 patients underwent surgical treatment with plates for fractures of the fingers and metacarpal region. Of these, 140 operations could be analyzed according to the inclusion criteria based on clinical and radiological parameters. Results: Three-quarters of the patients were male. The mean age at the time of surgery was 39.3±16 years. Falling was the leading cause for hand fractures, and the most common were fractures of the shaft (>52%). More than 15% were complex hand injuries with more than one fractured finger. The majority of patients were healthy non-smokers without systemic diseases and relevant medical history. Conclusion: The Stryker Finger Plates are safe implants with good results that are consistent with those reported in the literature. The trend is also toward stable-angle implants for fracture treatment of the finger, in order to enable the earliest possible functional, safe mobilization. Level of Evidence: Level: IV; outcome-study, retrospective.

Autoantibodies from patients with complex regional pain syndrome induce pro-inflammatory effects and functional disturbances on endothelial cells in vitro.

ABSTRACT: Complex regional pain syndrome (CRPS) is an inadequate local response after a limb trauma, which leads to severe pain and autonomic and trophic changes of the affected limb. Autoantibodies directed against human ß2 adrenergic and muscarinic M2 receptors (hß2AR and hM2R) have been described in CRPS patients previously. We analyzed sera from CRPS patients for autoantibodies against hß2AR, hM2R, and endothelial cells and investigated the functional effects of purified IgG, derived from 13 patients with CRPS, on endothelial cells. Eleven healthy controls, 7 radial fracture patients without CRPS, and 10 patients with peripheral arterial vascular disease served as control subjects. The CRPS-IgG, but not control IgG, bound to the surface of endothelial cells ( P < 0.001) and to hß2AR and hM2R ( P < 0.05), the latter being reversed by adding ß2AR and M2R antagonists. The CRPS-IgG led to an increased cytotoxicity and a reduced proliferation rate of endothelial cells, and by adding specific antagonists, the effect was neutralized. Regarding second messenger pathways, CRPS-IgG induced ERK1/2, p38, and STAT1 phosphorylation, whereas AKT phosphorylation was decreased at the protein level. In addition, increased expression of adhesion molecules (ICAM-1 and VCAM-1) on the mRNA level was induced by CRPS-IgG, thus inducing a pro-inflammatory condition of the endothelial cells. Our results show that patients with CRPS not only develop autoantibodies against hß2AR and hM2R, but these antibodies also interfere with endothelial cells, inducing functional effects on these in vitro, and thus might contribute to the pathophysiology of CRPS.

Intra-abdominal adhesion formation: does surgical approach matter? Questionnaire survey of South Asian surgeons and literature review.

AIM: The impact of postsurgical intra-abdominal adhesions, which represent a considerable burden for patients and health services, is often underestimated. Various factors influence adhesion formation, including the surgical approach. This study aimed to further understand the condition by investigating surgeons' perceptions of adhesion formation, particularly differences after laparoscopic and open surgery, and by performing a selective literature review. MATERIALS AND METHODS: South Asian surgeons attending endoscopy symposia in India and in Germany completed Likert-scale-based questionnaires on awareness of adhesion formation and associated consequences in gynecology. MEDLINE and PubMed were searched for articles published in 2000-2010 comparing laparoscopy and laparotomy in relation to adhesion formation. The results of the questionnaire study were then considered in view of findings from this review. RESULTS: In total, 43.1% (97/225) of questionnaires were completed. Respondents considered that laparoscopy caused fewer adhesions than laparotomy for all gynecological procedures. Although they believed their knowledge of adhesion formation was satisfactory, they widely underestimated the risk, giving estimated rates of 12.5% after laparoscopy and 36.3% after laparotomy. Twenty-eight studies were identified in the review. Most concluded that laparoscopy was less likely to cause adhesions than laparotomy but further statistical analysis was precluded because so many different definitions and classifications of adhesions had been used. CONCLUSIONS: The risk of adhesion formation was widely underestimated in the study group. Both the questionnaire study and the review concluded that laparoscopy results in less adhesion than laparotomy but further statistical comparison necessitates the development of standard definitions and classifications of adhesions.

Minimal-invasive posterior approach for total hip arthroplasty versus standard lateral approach.

In this prospective study we compared clinical and radiological results and rehabilitation progress of 64 patients who underwent total hip arthroplasty using the standard lateral approach with 64 patients operated with a minimal-invasive (MIS) posterior approach. The outcome of our study did not show any significant differences with regard to patient's safety such as complication rate and radiological assessment of the cup position. There was no difference in the duration of surgery, blood loss, hospital stay and postoperative leg length discrepancy. Rehabilitation milestones were achieved earlier by MIS patients and three and six months postoperatively, the Harris Hip Score of the MIS group was significantly higher.

[Surgical treatment of the ulnar styloid process using an angle-stable hook plate in fractures and symptomatic nonunions]. / Operative Versorgung des Processus styloideus ulnae mittels winkelstabiler Hakenplatte bei Frakturen und symptomatischen Pseudarthrosen.

OBJECTIVE: Anatomical reduction of dislocated fractures using an angle-stable hook plate. Surgical revision of symptomatic nonunions with the aim of bone regeneration. INDICATIONS: Dislocated fractures of the ulnar styloid process with involvement of the ulnar fovea. Combined fractures with instability of the distal radioulnar joint and symptomatic nonunions. CONTRAINDICATIONS: Undisplaced fractures of the ulnar styloid process and asymptomatic nonunions. SURGICAL TECHNIQUE: Dorsoradial access to the distal ulna between the 6th extensor tendon compartment and the tendon of the flexor carpi ulnaris muscle. Exposition of the fracture/nonunion. In case of nonunions, excision and freshening of the fracture ends. Reduction is carried out using the hooks of the plate, if necessary additional attachment of autologous cancellous bone in case of nonunions. Fixation of the plate over the gliding hole and subsequent filling of the angular stable screw holes. POSTOPERATIVE MANAGEMENT: Depending on the accompanying injury, immobilization in a forearm plaster splint for 1-2 weeks. Active movement exercises of the fingers from postoperative day 1, if necessary lymph drainage. After bone development, load build-up under ergotherapy guidance. RESULTS: Bony healing was achieved in 100% of our cases. The surgical treatment of symptomatic nonunions as well as dislocated fractures of the ulnar styloid process using an angle-stable hook plate has proven to be successful.

Long-Term Results of the Modular Physiological Wrist Prosthesis (MPW®) in Patients with Inflammatory Diseases.

The wrist is among the predilection sites of over 90% of cases of rheumatoid arthritis (RA). In advanced cases, total wrist arthroplasty (TWA) is an alternative to arthrodesis. The aim of this study is to present the long-term results of the modular physiological wrist prosthesis (MPW®) and to match them in context with the results of a standard population survey. In a retrospective study with follow-up, patients with an MPW® endoprosthesis were evaluated concerning the clinical and radiological outcome, complications were reviewed (incidence and type), and conversion to wrist fusion was assessed. Patient function measurements included the Mayo wrist score, the patient-specific wrist test, and therefore the DASH score (arm, shoulder, and hand). Thirty-four MPW® wrist prostheses were implanted in 32 patients, including thirty primary implantations and four changes of the type of the endoprosthesis. Sixteen patients (18 prostheses) underwent clinical and radiological follow-up. The average follow-up time was 8.5 years (1 to 16). Poor results of the MPW prosthesis are caused by the issues of balancing with luxation and increased PE wear. Salvage procedures included revision of the TWA or fusion. In successful cases, the flexion and extension movement averaged 40 degrees. The grip force was around 2.5 kg. The common DASH score was 79 points, with limited and problematic joints of the upper extremity. The MPW wrist prosthesis offered good pain relief and functional movement in over 80% of cases. The issues of dislocation and increased PE wear prevent better long-term results, as do the joints affected. A follow-up study with fittings under a contemporary anti-rheumatic therapy with biologicals suggests increasing score results. Type of study/level of evidence: Case series, IV.

Missed elbow fractures misdiagnosed as radial head subluxations.

Over a 36-month period, 11 children were treated in our department for fractures about the elbow which initially went undiagnosed, as they had first undergone reduction maneuvers for a suspected radial head subluxation, without prior imaging. The most frequent final diagnosis was supracondylar humerus fracture (n = 4). A fall was reported for six children (54.5%); the mechanism of injury remained unknown in four children (36.4%). In four of eleven children (36.4%) there was moderate or major soft tissue swelling at the time of first presentation, which is uncommon in radial head subluxation. Reduction of a suspected radial head subluxation without any prior radiological investigation can be recommended exclusively when the typical history of an abrupt traction by an (adult) attending person is positively reported. In every other case, radiographs should be done prior to any attempt at reduction.

Peri-Prosthetic Joint Infection after Finger Joint Arthroplasty.

Background: Endoprosthetic treatment of finger joints is an established procedure. However, data on peri-prosthetic finger joint infections (PJI) are rare. The goal of this retrospective study was to assess infection rates and treatment outcomes after PJI of the finger joints. Methods: Between 1984 and 2014, 1,195 finger joints (978 metacarpal and 217 proximal interphalangeal [PIP] joints) in 518 patients were treated. A retrospective record analysis was conducted. Besides demographic data, infection rates, types of revision surgery, and treatment outcomes were evaluated. Treatment strategies changed during the treatment period. Routinely assessed patient-reported outcome measures, namely the QuickDASH score, visual analogue scale (VAS), an everyday function score (activities of daily living; ADL), and an adapted Clayton score, were compared. Results: In 36 finger joints of 30 patients, a post-operative peri-prosthetic infection could be identified (3%). Infections occurred on average 3.8 years after arthroplasty. For meta-carpal phalangeal (MCP) joints, the best clinical outcomes could be observed after a two-stage revision procedure (QuickDASH score 86). Arthrodesis performed in a one-stage procedure achieved favorable outcomes in PIP joints (QuickDASH score 89). Re-infection mandating revision surgery occurred in seven joints in five patients (7/36; 19.4%). In 25 patients with 29 finger joints, there was no re-infection and no need for revision. Conclusion: Peri-prosthetic infection of finger joint prostheses occurs in approximately 3% of all cases, which is a higher rate than in the more common hip and knee procedures. For MCP joint revision surgery, a two-stage procedure seems to be the best treatment choice. For PIP joint revision, a single-stage revision with arthrodesis in a functional position achieves a good outcome.

Treatment of proximal fifth metatarsal fractures with an ulna hook plate.

INTRODUCTION: Fractures of the base of the fifth metatarsal bone present one of the commonest fractures of the metatarsal bones. Conventionally intramedullary screws and tension band wiring have been used as internal fixation methods. Lately hook plates have also served as an alternative fixation method. We hereby report on our experience with the hook plate used in treating fractures of the proximal fifth metatarsal. METHODS: 21 patients treated with the hook plate for proximal fifth metatarsal fractures were assessed clinically and radiologically. RESULTS: Average time to union in primarily treated fractures (n=18) was 7.7 weeks (range 4.5-16 weeks). Average time to return of activities of daily living (ADLs) was 10.3 weeks (range 4.5-37 weeks). The average AOFAS midfoot score was 30.4 preoperatively and 95.2 postoperatively (p<0.01). CONCLUSION: The ulna hook plate presents a suitable and adequate method of osteosynthesis used to primarily treat proximal fifth metatarsal fractures requiring surgical intervention with satisfactory post-operative outcomes.