[Treatment of symptomatic end-stage osteoarthritis of the ankle with anterolateral approach and an anatomical plate]

OBJECTIVE

The aim of this paper is to describe the anterolateral approach using an anatomical plate for ankle arthrodesis and to present the first mid-term results with this technique in a high-risk population.

INDICATIONS

The indication for arthrodesis of the ankle joint with this described technique is moderate to severe osteoarthritis of the ankle.

CONTRAINDICATIONS

In addition to the general contraindications typical of any operation, there is a specific contraindication in cases of active infection of the soft tissues and accompanying osteomyelitis at the ankle.

SURGICAL TECHNIQUE

The incision is made along the course of the peroneus tertius muscle. After that, the mobilization of the peroneus superficialis nerve is carried out, followed by the mobilization of the long extensor tendons, especially the extensor digitorum muscle in a medial direction opening the capsule and removal of the residual cartilage on the distal tibia and talus. Subsequently, the subchondral sclerosis is opened, and the implantation of a suitable osteosynthesis material, e.g., an anatomical angle-stable plate, is carried out. Finally, wound closure is performed involving the muscle belly of the extensor digitorum muscle covering the plate.

POSTOPERATIVE MANAGEMENT

Immobilization of the ankle for 5-7 days in a dorsal knee-high splint. Retention in a walker after decongestion for another 5 weeks. Increased loading can be done after X‑ray/computed tomography (CT) control from the 6th week.

RESULTS

In all, 11 patients were observed retrospectively for an average of 14 months. There were no complications. The European Foot and Ankle Society (EFAS) score improved significantly from 3.3 to 17.8 points. All patients were subjectively satisfied with the result and would have the operation again.

Iatrogenic Damage to Neurovascular and Soft Tissue Structures During Lateral Release of Hallux Valgus: A Comparative Anatomical Study of Minimally Invasive Versus Open Surgical Techniques

Lateral release is often an integral step in surgical correction of hallux valgus and can be performed using open or minimally invasive techniques. We investigated whether these techniques cause iatrogenic damage to arteries, nerves, tendons, or joint capsules. In this cadaver study, lateral release was performed on 9 pairs of specimens by a specialized foot surgeon. The specimens were randomly assigned to each group. The operations were followed by anatomical preparation, data collection, photo documentation, and statistical analysis. Iatrogenic damage to arteries, nerves, tendons, or joint capsules was rare, regardless of the surgical technique used. However, with the minimally invasive technique, the tendon of the extensor hallucis longus muscle and the sensitive terminal branches of the fibular nerve were at risk due to their anatomical proximity to the access portal. The deep transverse metatarsal ligament was potentially at risk if the adductor hallucis muscle was completely detached from the lateral sesamoid. When the deep transverse metatarsal ligament was transected there was risk of damaging the underlying plantar neurovascular structures. Both surgical techniques are safe in terms of the risk of injury to neighboring neurovascular and soft tissue structures.

The Correction Potential of the Lateral Release of the Hallux Valgus: A Comparative Anatomical Study of Minimally Invasive Versus Open Surgical Technique Using a Dorsal Approach

Background

Lateral release (LR) is an integral part of surgical correction of hallux valgus. A comparison was made between the open and minimally invasive LR techniques using a dorsal approach. The reliability and safety of the two methods were compared. Besides, the release of specific structures was investigated with special emphasis on ascertaining if the release was partial or a total one.

Methods

In this study on cadavers, LR was performed on nine pairs of foot and ankle specimens. The group assignments were randomized for each case. The operations were followed by anatomical preparation, data collection, photo documentation, and statistical analysis.

Results

A statistically significant advantage was observed with the open dorsal approach as there was a complete release of the adductor hallucis muscle from the lateral sesamoid and the lateral metatarsosesamoid ligament (p = 0.015 in each case). In terms of releasing the adductor hallucis muscle from the proximal phalanx, the lateral joint capsule, and the lateral collateral ligament, none of the investigated procedures showed better performance. However, open dorsal access tends to show a higher degree of release more frequently.

Conclusions

Splitting of the lateral joint capsule, including the lateral collateral ligament and lateral metatarsosesamoid ligament via the dorsal approach can be performed reliably and completely using the open surgical technique. The open dorsal technique shows better rates of detachment when the adductor hallucis muscle is released from the lateral sesamoid. Both techniques resulted in incomplete release of the adductor hallucis muscle from the proximal phalanx.

Study Type

Therapeutic-investigating the results of a treatment.

Level of Evidence

II (Prospective cohort study).

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-021-00575-3.

Anatomical Study of Sinus Tarsi-Based Lateral Lengthening Calcaneal Osteotomy

BACKGROUND

Lateral lengthening calcaneal osteotomy (LL-CO) is commonly performed as a treatment for an abducted midfoot in pes planovalgus deformity. The purpose of this study is to investigate potential damage to medial structures with a sinus tarsi LL-CO.

METHODS

Sixteen cadaver feet were used. Eight feet had an extended lateral approach, and 8 had a limited lateral (sinus tarsi) approach. All underwent a sinus tarsi LL-CO. Specimens were then dissected to identify inadvertent injury to medial structures.

RESULTS

Sinus tarsi LL-CO was associated with damage to the sustentaculum tali and medial articular facets in 56% and 62.5% of specimens, respectively. No anterior or posterior facet injuries were found, although 56% of specimens had a confluent medial and anterior facet.

CONCLUSION

Damage to the medial articular facet and sustentaculum is possible with a flat cut sinus tarsi LL-CO due to the curved nature of the relevant sinus tarsi and canal anatomy.

CLINICAL RELEVANCE

Sinus tarsi LL-CO needs to be performed with caution since damage to the subtalar joint is possible.

LEVEL OF EVIDENCE

Level II, prospective cohort study.

[Description of a technique that uses Lapidus arthrodesis plus osteochondral autotransplantation in the treatment of severe hallux rigidus]

OBJECTIVE

The objective of this technique is the treatment a severe hallux rigidus deformity by reorientation of an elevated first metatarsal using arthrodesis of the first tarsometatarsal joint and performing a one-step transplantation of an osteochondral graft, which is harvested from the first cuneiform, to the head of the first metatarsal bone.

INDICATIONS

Severe arthritis of the first metatarsophalangeal joint (MTP) stage 3 and 4 in the Vanore classification.

CONTRAINDICATIONS

General contraindications for a foot surgery; ankylosis of MTP joint; severe arthritis of the sesamoid joint; osteonecrosis; short first metatarsal; previous infection in the metatarsophalangeal joint; large cysts at the head of the first metatarsal.

SURGICAL TECHNIQUE

The first step is the preparation of the metatarsophalangeal and the first tarsometatarsal joint. After mobilizing the first metatarsal in a medioplantar direction, a cartilage-bone cylinder is removed from the articular surface of the medial cuneiform using special osteochondral autograft transfer system (OATS) instruments (Small Joint OATS, Arthrex medical instruments GmbH, Munich, Germany). This is followed by the arthrodesis of the first tarsometatarsal joint with reorientation of the position of the first metatarsal bone. Then the removed osteochondral cylinder is implanted into the articular surface of the first metatarsal head. After that the capsule is closed and the skin sutured.

POSTOPERATIVE MANAGEMENT

Postoperative management is guided mainly by the requirements of the first tarsometatarsal arthrodesis. When a plantar plate is used pain orientated full weightbearing is allowed in a postoperative shoe with a stiffened sole for 6-8 weeks. Physiotherapy is prescribed to exercise the first metatarsophalangeal joint.

RESULTS

In the study, 5 patients were treated with the method described in the years 2011-2012 and were followed up for a period of 2 years. All of these patients were subjectively satisfied with the outcome of the operation. There were no relevant surgery-associated complications.

[Cartilage chip transplantation for cartilage defects of the first metatarsophalangeal joint]

OBJECTIVE

Treatment of circumscribed cartilage defects in the first metatarsophalangeal joint (MTP1) using autologous cartilage fragments.

INDICATIONS

Full thickness cartilage defects (ICRS IV) or focal osteoarthritis in combination with hallux rigidus.

CONTRAINDICATIONS

Pre-existing ankylosis of the metatarsophalangeal joint; global osteoarthritis of the joint; advanced osteoarthritis of the sesamoidal articulation; osteonecrotic cysts in the head of the first metatarsal bone.

SURGICAL TECHNIQUE

Preparation of the metatarsophalangeal joint. Mobilization of the first metatarsal head. Harvesting of the cartilage fragments from the dorsal rim portion as part of the cheilectomy. Mincing the cartilage fragments with a 3.0 mm shaver in sterile conditions. Augmenting the cartilage fragments with autologous conditioned plasma (ACP). Preparing the defect area and creation of a "contained" defect. Replantation of the resulting minced cartilage mass into the defect of the articular surface on the first metatarsal head.

POSTOPERATIVE MANAGEMENT

Immobilization of the MTP1 for 48 h. Intensive physiotherapy for 3 months. Full weight bearing after reduced swelling.

RESULTS

In 2020, 5 patients were treated with the method described and followed up for a period of 1 year. All patients were subjectively satisfied with the result of the operation. There were no relevant surgery-associated complications.

Comparison of Ligament-Repair Techniques for the Syndesmosis: A Simulated Cadaveric Weight-Bearing Computed Tomography Analysis

Although the literature describes a variety of reconstructive techniques for the syndesmosis, only few studies offer comparative data. Therefore, the authors compared 2 different ligament repair techniques for the syndesmosis. Sixteen paired fresh-frozen human cadaveric lower limbs were embedded in polymethyl methacrylate mid-calf and placed in a custom-made weightbearing simulation frame. Computed tomography scans of each limb were obtained in a simulated foot-flat loading (75N) and single-leg stance (700N) in 5 different foot positions (previously reported data). One of each pair was then reconstructed via 1 of 2 methods: a free medial Achilles tendon autograft or a long peroneal tendon ligament repair. The specimens were rescanned, compared with their respective intact states and directly with each other. Measurements of fibular diastasis, rotation, anteroposterior translation, mediolateral translation, and fibular shortening were performed on the axial cuts of the computed tomography scans, 1 cm proximal to the roof of the plafond. There was no significant difference in fibular positioning with direct comparison of the reconstructions. Comparisons with their respective intact states, however, showed differences in their abilities to control reduction, most notably in the externally rotated and dorsiflexed positions of the foot. Neither reconstruction was clearly superior in restoring physiologic conditions. Only with a comparison of each technique to its respective intact state were differences between the techniques revealed, a benefit of this particular testing method.

Arthroscopic Minced Cartilage Implantation for Chondral Lesions at the Talus: A Technical Note

In the past few years, autologous chondrocyte implantation has been shown to be the most suitable cartilage reconstructive technique with the best tissue quality. Although this method is part of the standard surgical repertoire in the knee joint, it has so far not been an established method in the ankle because there are no prospective randomized controlled studies to prove a significant advantage over alternative methods of cartilage repair. The methods most frequently used in this context (e.g., marrow stimulation techniques) can, however, at most generate hyaline-like and thus biomechanically inferior regenerates. Minced cartilage implantation, on the other hand, is a relatively simple and cost-effective 1-step procedure with promising biological potential and-at least in the knee joint-satisfactory clinical results. We present an arthroscopic surgical technique by which the surgeon can apply autologous chondrocytes in a 1-step procedure (AutoCart; Arthrex, Munich, Germany) to treat articular cartilage defects in the ankle joint.

Biological responses to individualized small titanium implants for the treatment of focal full-thickness knee cartilage defects in a sheep model

BACKGROUND

The present study aimed to evaluate the functional, radiological and histological outcome of a customized focal implant for the treatment of focal full-thickness cartilage defects in sheep.

METHODS

The study used magnetic resonance imaging data as the basis for construction of the titanium implant using a three-dimensional printing technique. This was then placed on the medial condyle of the knee joint in eight sheep and left in place in vivo over a period of six months. Following euthanasia, the local biological response was analyzed using micro-computed tomography, light microscopy and histological evaluation (International Cartilage Repair Society (ICRS) score). The variables were analyzed using a generalized linear mixed model. Odds ratios were given with 95% confidence intervals.

RESULTS

The osseointegration rate was 62.1% (SD 3.9%). All implants were prone to the neighboring cartilage bed (4.4-1096.1 μm). Using the IRCS score, the elements 'surface', 'matrix', 'cell distribution' and 'cell population' all showed pathological changes on the operated side, although these did not correlate with implant elevation. On average, a difference of 0.7 mm (±2 mm) was found between the digitally planned implant and the real implant.

CONCLUSIONS

As a result of imprecise segmentation and difficult preparation conditions at the prosthesis bed, as well as changes at the surface of the implant over the operational lifetime of the prosthesis, it must be stated that the approach implemented here of using a customized implant for the treatment of focal full-thickness cartilage defects at the knee did not meet our expectations.

Release of Antibiotics Out of a Moldable Collagen-β-Tricalciumphosphate-Composite Compared to Two Calcium Phosphate Granules

Bacterial bone infections after revision surgeries and diseases, like osteomyelitis, are still a challenge with regard to surgical treatments. Local bone infections were treated with antibiotics directly or by controlled drug-releasing scaffolds, like polymethylmethacrylate (PMMA) spheres, which have to be removed at a later stage, but there is a risk of a bacterial contamination during the removement. Therefore, biomaterials loaded with antibiotics for controlled release could be the method of choice: The biomaterials degrade during the drug release, therefore, there is no need for a second surgery to remove the drug eluting agent. Even non-resorbable bone materials are available (e.g., hydroxyapatite (HA)) or resorbable bone graft materials (e.g., beta-tricalcium phosphate (β-TCP)) that will be replaced by newly formed bone. Composite materials with organic additives (e.g., collagen) supports the handling during surgery and enhances the drug loading capacity, as well as the drug releasing time. The purpose of this study was to investigate the loading capacity and the release rate of Vancomycin and Gentamicin on TCP and HA granules in the shape of a degradable scaffold compared to composite materials from TCP mixed with porcine collagen. Its antibacterial efficacy to a more elementary drug with eluting in aqueous solution was examined. The loading capacity of the biomaterials was measured and compared according to the Minimum Inhibition Concentration (MIC) and the Minimum Biofilm Eradication Concentration (MBEC) of a bacterial biofilm after 24 h aging. Antibiotic elution and concentration of gentamycin and vancomycin, as well as inhibition zones, were measured by using the Quantitative Microparticle Systems (QMS) immunoassays. The antibiotic concentration was determined by the automated Beckman Coulter (BC) chemistry device. For examination of the antibacterial activity, inhibition zone diameters were measured. Generally, the antibiotic release is more pronounced during the first couple of days than later. Both TCP granules and HA granules experienced a significantly decline of antibiotics release during the first three days. After the fourth day and beyond, the antibiotic release was below the detection threshold. The antibiotic release of the composite material TCP and porcine collagen declined less drastically and was still in the frame of the specification during the first nine days. There was no significant evidence of interaction effect between antibiotic and material, i.e., the fitted lines for Gentamycin and Vancomycin are almost parallel. During this first in vitro study, β-TCP-Collagen composites shows a significantly higher loading capacity and a steadily release of the antibiotics Gentamycin and Vancomycin, compared to the also used TCP and HA Granules.

Risk factors for pelvic insufficiency fractures and outcome after conservative therapy

PURPOSE

The prevalence of osteoporosis has continuously increased over the past decades and it is set to increase substantially as life expectancy rises steadily. Fragility or osteoporotic fractures of the pelvis often occur after low energy falls e.g. from standing, however, some patients present with assumed insufficiency fractures of the pelvis without a previous trauma. Osteoporotic fractures impose a tremendous economic burden and these fractures deserve attention as they lead to a decrease in mobility with an increase in dependency and are associated with a high rate of mortality. To date, little is known about potential risk factors for pelvic insufficiency fractures. Furthermore, information on clinical outcome is scarce. In view of this rather limited knowledge, we aimed to identify potential risk factors for pelvic insufficiency fractures and to collect information on their short- and long-term outcomes.

METHODS

Files of all consecutive patients admitted between January 2010 and December 2013 for a pelvic insufficiency fracture were enrolled in this study. Pelvic fractures that occurred on tumorous bone or after high-energy trauma were excluded. Fractures of the pelvis included all pelvic bones except the coccyx. For all patients, we recorded clinical and biological parameters available from their medical history. For comparison, the same biological and clinical parameters were evaluated in an age matched control group of 1083 patients aged over 70 who were admitted to our orthopaedic department to undergo knee or hip arthroplasty. The statistical analyses used or Fisher test for percentages comparison, 2-tailed t-tests and Mann Whitney for mean comparison. To determine what factors are predictors and what factors are confounders of pelvic insufficiency fractures, multivariate linear regression analysis using the fracture as a continuous variable was performed.

RESULTS

Ninety-three patients with a pelvic insufficiency fracture were identified. Following the Rommens and Hofmann classification for fragility fractures of the pelvis (FFP), 51 were FFP Type Ia, 26 were FFP Type IIb lesions and 26 were FFP Type IIc. Osteoporosis was found to be significantly associated with pelvic insufficiency fractures (p=0.003), as was hypertension (p=0.036), diabetes (p=0.021), vitamin D deficiency (p=0.004), hypocalcaemia (p=0.002) and nicotine abuse (p=0.0012) after adjustment for possible confounders in the multivariate linear regression analysis. Comparing the autonomous state before and after pelvic fracture, a high loss of autonomy was observed. Patients needing daily assistance nearly doubled their number. Overall mortality was high (20%).

CONCLUSIONS

In conclusion, this study showed multiple risk factors for pelvic insufficiency fractures. Some, like vitamin D deficiency, can benefit easy preventive measures. Outcome of conservative therapy is poor, with loss of social and physical independence and autonomy. The mortality rate is high. Efforts should be made in preventing pelvic insufficiency fractures. All patients should be treated for the severe osteoporosis being associated with these fracture type.

Is there an association between low serum 25-OH-D levels and the length of hospital stay in orthopaedic patients after arthroplasty?

Background

The purpose of this observational study was to evaluate serum levels of 25-OH-D in patients scheduled to undergo elective hip or knee arthroplasty. We hypothesised that 25-OH-D level is an independent risk factor for length of stay in orthopaedic patients after elective hip or knee arthoplasty.

Materials and methods

25-OH-D levels were measured in 1083 patients admitted to an orthopaedic surgery department to undergo elective hip or knee arthroplasty. Comparisons were performed using Chi square or Student’s t test, followed by univariate and multiple linear regression analysis examining the correlation between the length of stay in the orthopaedic department and 25-OH-D level while adjusting for possible confounders.

Results

Overall, 86 % of patients had insufficient serum levels of 25-OH-D, and over 60 % were vitamin D deficient. The mean length of stay was 13.2 ± 8.3 days. In patients with hypovitaminosis D, the length of stay was significantly longer compared to patients with normal serum 25-OH-D levels (15.6 ± 7.2 compared to 11.3 ± 7.9 days, P = 0.014). In univariate analyses, serum 25-OH-D level was inversely related to the length of stay in our orthopaedic department compared to patients with normal vitamin D levels (r = −0.16; P = 0.008). In multivariate analyses, the length of stay remained significantly associated with low 25-OH-D levels (P = 0.002), indicating that low vitamin D levels increase the length of stay.

Conclusions

We found a high frequency of hypovitaminosis D among orthopaedic patients scheduled to undergo elective arthroplastic surgery. Low vitamin D levels showed a significant inverse association to the length of stay in our orthopaedic department. Patients with vitamin D levels in the target range were hospitalised 4.3 days less than patients with hypovitaminosis D.

Level 3 of evidence according to “The Oxford 2011 levels of evidence”.

In-vivo analysis of epicutaneous pressure distribution beneath a femoral tourniquet--an observational study

Background

Compression of the tissue beneath tourniquets used in limb surgery is associated with varying degrees of soft tissue damage. The interaction between fluids and applied pressure seems to play an important role in the appearance of skin lesions. The extent of the transfer of force between the tourniquet and the skin, however, has yet to be studied. The aim of the present study was to quantify in-vivo the transfer of pressure between a tourniquet and the skin of the thigh.

Methods

Pressure under the tourniquet was measured using sensors in 25 consecutive patients over the course of elective surgical procedures. Linear mixed modeling was used to assess the homogeneity of the distribution of pressure around the circumference of the limb, variation in pressure values over time, and the influence of limb circumference and the Body-Mass-Index (BMI) on pressure transfer.

Results

Mean pressure on the skin was significantly lower than the inner pressure of the cuff (5.95%, 20.5 ± 9.36 mmHg, p < 0.01). There was a discrete, but significant (p < 0.001) increase in pressure within the first twenty minutes after inflation. Sensors located in the area of overlap of the cuff registered significantly higher pressure values (p < 0.01). BMI and leg circumference had no influence on the transfer of pressure to the surface of the skin (p = 0.88 and p = 0.51).

Conclusions

Pressure transfer around the circumference of the limb was distributed inhomogeneously. The measurement series revealed a global pressure drop compared to the initial pressure of the cuff. No relationship could be demonstrated between the pressure transferred to the skin and the BMI or limb circumference.

Open versus endoscopic bone resection of the dorsolateral calcaneal edge: a cadaveric analysis comparing three dimensional CT scans

BACKGROUND

It has been claimed that endoscopic calcaneoplasty offers some advantages over open techniques in the surgical treatment of Haglund's deformity due to reduced postoperative complications like stiffness and pain. Bony over-resection places patients at risk of these complications. The resulting question with regard to the quantitative differences of the extent of the bone removed using these two techniques has not yet been answered. The purpose of the study was to determine the resection volume of calcaneal bone for open and endoscopic surgical techniques.

METHODS

16 feet obtained from body donors were operated on in equal parts using either open surgical or endoscopic techniques, with the technique selected on a random basis. High-resolution CT scans were obtained before and after the interventional procedure and analysed to obtain 3-D polygon models. Post-operative models were subtracted from pre-operative models to provide the volume change resulting from the intervention. This was then correlated with the bone mineral density (BMD) of the preparation.

RESULTS

The extent of bony resection was greater in open surgical techniques than in endoscopic approaches. The average volume of bone resection was 0.80 (±0.34) cm(3) in the endoscopic group and 3.04 (±2.91) cm(3) in the group that underwent open surgery. After adjustment for bone mineral density the extent of the resection was significantly larger (p = 0.018) in the group undergoing open surgery. The two groups did not differ significantly with regard to BMD (p > 0.1). The extent of the resection fell by 0.011 cm(3) per 1 mg/cm(3) areal bone mineral density, i.e., a slightly lower degree of bone resection was associated with a higher bone mineral density.

CONCLUSIONS

Assuming that the resection volume was adequate to treat the patient's complaints a smaller resection volume seen in our study using an endoscopic technique might lead to fewer postoperative complaints and faster recovery.

Intraosseous fixation compared to plantar plate fixation for first metatarsocuneiform arthrodesis: a cadaveric biomechanical analysis

BACKGROUND

Metatarsocuneiform (MTC) fusion is a treatment option for management of hallux valgus. We compared the biomechanical characteristics of an internal fixation device with plantar plate fixation.

METHODS

Seven matched pairs of feet from human cadavers were used to compare the intramedullary (IM) device plus compression screw to plantar plate combined with a compression screw. Specimen constructs were loaded in a cyclic 4-point bending test. We obtained initial/final stiffness, maximum load, and number of cycles to failure. Bone mineral density was measured with peripheral quantitative computed tomography. Performance was compared using time to event analysis with number of cycles as time variable, and a proportional hazard model including shared frailty model fitted with treatment and bone mineral density as covariates.

RESULTS

On average the plates failed after 7517 cycles and a maximum load of 167 N, while the IM-implants failed on average after 2946 cycles and a maximum load of 69 N. In all pairs the 1 treated with IM-implant failed earlier than the 1 treated with a plate (hazard ratio for IM-implant versus plate was 79.9 (95% confidence interval [6.1, 1052.2], P = .0009). The initial stiffness was 131 N/mm for the plantar plate and 43.3 N/mm for the IM implant. Initial stiffness (r = .955) and final stiffness (r = .952) were strongly related to the number of cycles to failure. Bone mineral density had no effect on the number of cycles to failure.

CONCLUSION

Plantar plate fixation created a stronger and stiffer construct than IM fixation.

CLINICAL RELEVANCE

A stiffer construct can reduce the risk of nonunion and shorten the period of non-weight-bearing.

Vitamin D insufficiency in the elderly orthopaedic patient: an epidemic phenomenon

PURPOSE

The purpose of this observational study was to evaluate serum levels of 25-OH-D of elderly patients presenting with orthopaedic illness. Furthermore, we enquired about potential confounders and risk factors of hypovitaminosis D in comorbidities and daily medication of the elderly.

METHODS

Vitamin D levels in 1,083 patients aged >70 years and admitted to an orthopaedic surgery department were measured. Univariate and multivariate analyses were used to assess risk factors for insufficient vitamin D levels.

RESULTS

Overall, 86 % of patients had insufficient serum levels of 25-OH-D and >60 % were vitamin D deficient. Serum vitamin D levels were lower during winter and months with fewer sunshine hours. Patients presenting with obesity, hypertension and osteoporosis were more likely to have low vitamin D levels.

CONCLUSIONS

We found a high prevalence of hypovitaminosis D in elderly, nonhospitalized orthopaedic patients. Given the well-known effects of vitamin D on bone metabolism and muscle health, as well as its nonskeletal effects, vitamin D insufficiency may have a negative impact.

Is there an association between periprosthetic joint infection and low vitamin D levels?

PURPOSE

Vitamin D is increasingly being recognized as an important mediator of immune function and may have a preventive role in the pathogenesis of periprosthetic joint infection. To the best of our knowledge, no other study has examined possible associations between periprosthetic joint infection and vitamin D deficiency. We investigated the rate of vitamin D deficiency in patients treated for periprosthetic joint infection and whether vitamin D deficiency is independent of other risk factors for vitamin D deficiency in patients with periprosthetic joint infection.

METHODS

Serum 25-hydroxyvitamin D (25OHD) levels of every patient scheduled to receive a total prosthesis either of the hip, knee, or shoulder in the orthopaedic department of the Johannes-Guttenberg-University Hospital in Mainz, Germany (109 patients), were measured after admission. Furthermore, serum 25OHD levels were measured for every patient presenting with periprosthetic joint infection (n = 50) or aseptic loosening of the prosthesis (n = 31) scheduled to undergo revision surgery. The prevalence of normal (> 30 ng/ml), insufficient (20-30 ng/ml), and deficient (<20 ng/ml) 25OHD levels was determined.

RESULTS

All tested patient subgroups showed low vitamin D levels. Statistical analysis found no significant difference in vitamin D levels comparing patients with prosthesis and patients with aseptic prosthesis loosening (p = 0.58). Significant differences in 25OHD levels were found comparing patients with periprosthetic joint infection and patients scheduled for primary arthroplasty (p < 0.001). In addition, we found a significant difference (p < 0,001) in 25OHD levels of patients with periprosthetic joint infection compared with patients with aseptic prosthesis loosening.

CONCLUSION

We found a high frequency of vitamin D deficiency in patients being treated by primary arthroplasty and those with aseptic joint prosthetic loosening and periprosthetic joint infection. Vitamin D deficiency was severe in patients with periprosthetic joint infection.

[Epidural injection shows no advantages over oral medication and physiotherapy in the treatment of sciatica, irrespective of the duration of symptoms]

BACKGROUND

The study presented here investigated the short-term effectiveness of one-off lumbar caudal epidural injection (EI) in sciatica in relationship to the reported duration of pain.

MATERIALS AND METHODS

This retrospective analysis involved 106 consecutive in-patients who received either conservative treatment (Group I) or an additional EI on the first day of their treatment (Group II). Both groups were divided according to the duration of symptoms at the time of admission (less than three months, or more than six months). Propensity score matching was performed for the whole collective and the resulting subgroups. This incorporated gender, age and pain intensity at the time of admission. The target parameter were changes on a visual analogue scale (VAS) of pain intensity on days D1, D3, and D10 depending on the respective treatment. A routine evaluation of the mental variables anxiety, depression and somatisation was performed as part of the examination upon admission and their relationship to the success of treatment was later assessed.

RESULTS

The mean age of the patients was 61.7 (± 11.6) in Group I and 63.6 (± 13.6) in Group II. 59 % of the patients were female (n = 63). The Lasègue sign was prevalent in 45 % of Group I and 51 % of Group II. The intensity of pain on the day of admission was similar in both groups (7.0 ± 1.0 for Group I, 6.7 ± 1.8 for Group II). The length of stay on the ward was also similar in both groups (10.2 ± 3.9 and 9.4 ± 3.7 d, respectively). It was found that, independent of the duration of symptoms, injection treatment was significantly more effective than conservative treatment only in the early stages (D1 and D3, p < 0.001). No differences could be found in the expression of these mental variables between treatment groups, as these factors showed no influence on the results of therapy.

CONCLUSIONS

In the context of acute treatment a once only lumbar caudal epidural injection represents at most a short-term effectiveness for the therapy of sciatica. The results presented here indicate that neither the duration of symptoms nor the measured psychometric variables show any effect on the success of therapy.

In vitro elution characteristics of gentamicin and vancomycin from synthetic bone graft substitutes

Objects:

Beta tricalciumphosphate pellets loaded with individualized antibiotics may represent novel options in the treatment of osteomyelitis and infectious bone disease. Here, the in vitro antibiotic elution of vancomycin and gentamicin from the synthetic bone graft substitutes Cerasorb^® and Cerasorb M^® was tested.

Methods:

Antibiotic elution and concentration of gentamcin and vancomycin were measured using photometrically-based measurement and homogeneous particle-enhanced turbidimetric inhibition immunoassays (PETINIA).

Results:

Initially both materials showed a high release of the loaded antibiotics, with Cerasorb M^® showing lower release levels for gentamicin and vancomycin than Cerasorb^®. Gentamicin concentrations of Cerasorb M granules and Cerasorb were below the minimum detectiontreshold until day four and six of the experiment respectively. The vancomycin release-level followed a similar pattern, although the vancomycin concentration eluted by Cerasorb M^® granules stayed above the detection threshold during the experimental time.

Conclusions:

Cerasorb^® and Cersorb M^® may represent a new treatment option in osteomyelitis and infectious bone disease.

Vitamin D deficiency in orthopaedic patients: a single center analysis

Vitamin D is essential to bone health and is a major regulator of calcium homeostasis. Many recent reports demonstrated worldwide high rates of vitamin D deficiency, but few studies have been published on the vitamin D status of orthopaedic patients. The present study aimed to investigate the extent of hypovitaminosis D of orthopaedic patients and possible variations in vitamin D status according to the body region which was scheduled to undergo surgery. We measured the vitamin D level of 1119 patients consecutively admitted to an orthopaedic surgery department of a university hospital in Germany in 2011. The prevalence of normal (< or =30 ng/ml), insufficient (20-30 ng/ml) and deficient (< or =20 ng/ml) 25-OH-D levels was determined. Serum Vitamin D levels and rates of insufficiency and deficiency were compared between the different cohorts using two-tailed tests. The level of significance was set at p < or =0.05. The serum 25-OH-D levels for all participants were normally distributed, with a mean of 2057 ng/ml. Overall, we noted an alarmingly high rate of vitamin D insufficiency or deficiency among orthopaedic patients. No significant difference was found related with the various body regions scheduled to undergo surgery. Given the well-known effects of vitamin D on bone metabolism and muscle health, vitamin D insufficiency may negatively affect patients.

Is there an epidemic vitamin D deficiency in German orthopaedic patients?

BACKGROUND

Vitamin D plays an essential role in bone health and muscle function. Some studies have shown a widespread rate of vitamin D deficiency in the general population, but few have reported on the vitamin D status of orthopaedic patients.

QUESTIONS/PURPOSES

We investigated (1) the extent of hypovitaminosis D in orthopaedic patients, (2) seasonal variations in vitamin D levels, and (3) possible risk factors for insufficient vitamin D levels.

METHODS

Vitamin D levels in 1119 patients consecutively admitted to an orthopaedic surgery department in 2011 were measured. To investigate the correlation between climate factors and vitamin D levels, the sunshine hours for each month in 2011 were collected by Deutscher Wetterdienst (the German weather service) in the region where most tested patients lived. The prevalence of normal (> 30 ng/mL), insufficient (20-30 ng/mL), and deficient (< 20 ng/mL) 25-hydroxyvitamin D levels was determined. Univariate and multivariate analyses were used to assess risk factors for insufficient vitamin D levels.

RESULTS

Overall, 84% of patients had insufficient levels of vitamin D and 60% were vitamin D deficient. Only 15% were in the target range of 30 to 60 ng/mL. The prevalence of low vitamin D levels was greater during winter and months with fewer sunshine hours. Vitamin D levels did not vary according to age, sex, and disease. Individuals with obesity, hypertension, and osteoporosis were more likely to have low vitamin D levels compared with their healthy counterparts.

CONCLUSIONS

There is an alarmingly high rate of hypovitaminosis D and vitamin D deficiency among orthopaedic patients in this region of Germany, whose latitude (50° N) is approximately the same as those of Vancouver (49°, 15' N) and Paris (48°, 51' N). Given the well-known effects on bone metabolism and muscle health, low vitamin D levels may negatively affect patients. Screening and treating hypovitaminosis D appears to be important in this patient population.

[Acute pain management after orthopaedic surgery]

Provision of sufficient post-operative pain therapy is an obligation in the clinical management of patients. A wide range of medical, technical and organizational options is used to improve post-operative pain management in orthopaedic surgery. Measurement of pain is as important as the correct use of analgesics and application techniques. Standardized pain therapy algorithms should facilitate autonomous treatment of patients. Additional procedures like patient-controlled analgesia or local catheter for pain are necessary for individualized or operation-specific pain therapy. The balanced combination in postoperative pain therapy could reduce side effects and complication rates, increase mobility and enhance patient satisfaction.

Sequenzielles laterales Weichteilrelease an der Großzehe: eine anatomische Studie

AIM

Lateral release is a substantial component of the distal soft tissue procedure, which plays a major role in the framework of the lapidus-fusion and the near-to-basis osteotomy in the hallux valgus surgery. The extent of release which is reached during this procedure is controversially discussed. The goal of this anatomic study was the evaluation of the effect of the sequential disconnection of lateral contraction structures on the alignment of the large toe.

METHOD

On 8 anatomical hallux valgus preparations in which each foot was fastened in a holding device under defined continuous lateral pull, the soft tissue at the lateral aspect of the large toe was surgically split in the following sequential order: the lateral joint capsule, the tendon of the adductor hallucis muscle and afterwards the transverse metatarsal ligament. Before each procedure an X-ray was taken. We documented the different changes of the hallux valgus angle, the intermetatarsal 1/2 angle as well as the proximal and distal articulation angles.

RESULTS

The hallux valgus angle was predominantly and significantly improved by capsule splitting and tenotomy of the tendon of the adductor hallucis muscle. A significant correction of the intermetatarsal angle did not take place however.

CONCLUSION

It was shown that the substantial element of an effective distal soft tissue procedure for hallux valgus is the splitting of the capsule. The disconnection of the transverse metatarsal ligament did not lead to a further correction and can therefore be neglected.

Mutation of the gene encoding cellular retinaldehyde-binding protein in autosomal recessive retinitis pigmentosa

Inadequate levels of all-trans-retinol in the blood cause retinal dysfunction; hence, genes implicated in retinal vitamin-A metabolism represent candidates for inherited retinal degenerations. In the current study, molecular genetic analysis of a consanguineous pedigree segregating for non-syndromic autosomal recessive retinitis pigmentosa (arRP) indicated that the affected siblings were homozygous by descent for a G4763A nucleotide substitution in RLBP1, the gene encoding cellular retinaldehyde-binding protein (CRALBP). This substitution is predicted to replace an arginine with glutamine at residue 150. CRALBP is not expressed in photoreceptors but is abundant in the retinal pigment epithelium (RPE) and Müller cells of the neuroretina, where it carries 11-cis-retinol and 11-cis-retinaldehyde. When expressed in bacteria, recombinant CRALBP (rCRALBP) containing the R150Q substitution was less soluble than wild-type rCRALBP. Mutant rCRALBP was purified from the soluble cell lysate and the protein structure was verified by mass spectrometry. The mutant protein lacked the ability to bind 11-cis-retinaldehyde. These findings suggest that arRP in the current pedigree results from a lack of functional CRALBP, presumably leading to disruption of retinal vitamin-A metabolism.

Follitropin conformational stability mediated by loop 2 beta effects follitropin-receptor interaction

Follicle-stimulating hormone (FSH) is in the family of pituitary/placental glycoprotein hormones which also includes luteinizing hormone (LH), chorionic gonadotropin (hCG), and thyroid-stimulating hormone. These hormones are heterodimers composed of common alpha- and similar but unique beta-subunits. The 21 amino acid loop between Y33 and F53 of the FSH beta-subunit (L2 beta) can be switched into L2 beta of hCG beta without a loss of receptor binding, yet mutation of hFSH beta 37LVY39 to 37AAA39 was antecendent to a 20-fold reduction in receptor binding (based on ID50). A mutation in the LH beta gene, which causes Q54 to be R, causes hypogonadism. This residue is conserved in the glycoprotein hormones and corresponds to Q48 in hFSH beta. Mutation of hFSH beta 48QKTCT52 to 48AAACA52 resulted in a failure of heterodimer formation. In the current study single mutations were made to pinpoint which of the seven hFSH beta residues in the 37LVY39 to 37AAA39 and the 48QKTCT52 to 48AAACA52 mutants were responsible for the observed phenotypes. A single mutation of T52 to alanine was sufficient to cause a reduction in expression of heterodimeric hormone. Single mutants Q48A, T50A, V38A, Y39A, and, to a lesser extent, T52A formed heterodimer. However, these hFSH mutants were markedly unstable at pH 2.0. Thus, acid dissociation can be used to reveal metastable forms of this protein. Mutant hFSH beta Q48A was also 8-fold less active than wild-type hFSH when assayed for binding to hFSH receptors. hFSH beta V38A and Y39A mutants affected receptor binding; however, neither mutation alone caused greater than a 2-fold decrease in receptor binding activity. In summary, these results identify single important residues in the long loop (between Y33 and F53) of the hFSH beta-subunit which are required for proper subunit interactions that provide conformational stability which in turn is necessary for FSH-receptor interaction.

Scanning-alanine mutagenesis of long loop residues 33-53 in follicle stimulating hormone beta subunit

Follicle stimulating hormone (FSH) is a gonadotropin and member of the pituitary/placental glycoprotein hormone family which bind to G-protein-coupled receptors. These hormones are heterodimers composed of a common alpha and distinct beta -subunits. Previous experimental evidence suggested that the FSH beta -subunit long loop comprised of amino acids Tyr33 to Phe53 is involved in receptor binding and activation and in subunit interaction. According to recently reported crystal structures of human chorionic gonadotropin (hCG), the homologous long loop of the beta -subunit of hCG associates with the alpha -subunit and is partially exposed to solvent. This report describes the results of scanning alanine mutagenesis used to determine if amino acid side chains in this region of the molecule are required for receptor binding and/or subunit contact. Five mutations were made which spanned this loop and the mutant FSH beta-subunits were co-expressed with alpha-subunit in a Baculovirus-infected insect-cell expression system. Mutation of 48QKTCT52 to 48AAACA52 produced a FSH beta-subunit that failed to form heterodimer, consistent with the crystal structure of hCG which shows these amino acids are buried at the subunit interface. The four remaining mutants produced heterodimer and were assayed for binding to and activation of human FSH receptors. Mutation of 37LVY39 to 37AAA39 caused a 20-fold reduction binding (ID50 of 7.0 nM compared with 0.3 nM for wildtype). Mutation of 34TRDL37 to 34AAAA37 or 44RPKI47 to 44APAA47 caused lesser but measurable effects with ID50 values of 1.1 nM and 1.9 nM, respectively. The (40)KDPA(43) to 40KDPA43 to 40AAPA43 mutation had little effect on receptor binding (ID50 = 0.5 nM).

Identification of amino acids in the C-terminal region of human follicle-stimulating hormone (FSH) beta-subunit involved in binding to human FSH receptor

Recent analyses of human FSH (hFSH) using antipeptide antibodies, monoclonal antibodies, and chimeric constructions of hCG/hFSH strongly suggest that the C-terminal region, including residues 81-100 of the hFSH beta-subunit, is involved in subunit association as well as hFSH heterodimer binding and/or activation of receptor. To test this hypothesis, site-directed mutagenesis was used to generate five triple alanine mutants of the C-terminal region of hFSH beta: Q81, H83, G85; K86, D88, S89; D90, S91, T92; D93, T95, V96; and R97, G98, L99. The baculovirus-infected insect cell system was used for expression. High Five cells were infected with virus harboring either delta hFSH beta complementary DNA (cDNA) or wild-type hFSH beta (hFSH beta wt) cDNA and coinfected with virus containing hFSH alpha cDNA. After infections, media were assayed for FSH using a heterodimer-specific enzyme-linked immunosorbent capture assay. All delta hFSH beta subunits formed heterodimers with hFSH alpha wt subunit and were secreted in the medium. These results suggest, for all five mutants, that side chains of amino acids substituted with alanine had no significant role in subunit association. The FSHs delta hFSH and hFSHwt were tested in a RRA, using cell lines that express the hFSH receptor, to determine if there were any changes in binding activity. Similarly, delta hFSH and hFSHwt were compared for receptor activation by measuring the levels of progesterone production in an in vitro FSH bioassay. delta hFSH-(93-96) exhibited minimal binding activity and no detectable steroidogenic activity. delta hFSH-(97-99) showed reduced binding affinity compared with that of hFSHwt, whereas the binding potency and bioactivity of the remaining delta hFSH were comparable to those of hFSHwt. These data demonstrate that within the hFSH beta-(81-99) region, FSH receptor-binding sites are contained within the sequence 93-99.

Site-directed alanine mutagenesis of Phe33, Arg35, and Arg42-Ser43-Lys44 in the human gonadotropin alpha-subunit

Residues Phe33 and Arg35, individually, and a composite mutation of residues Arg42, Ser43, and Lys44 were changed to alanine in the human glycoprotein hormone common alpha-subunit using site-directed mutagenesis. These specific residues are highly conserved across species and have by chemical modification and synthetic peptide approaches been implicated in the binding of human chorionic gonadotropin (hCG) to leutinizing hormone (LH) receptor. In the present study we tested the hypothesis that specific alpha-subunit amino acid residues which stabilize the hormone receptor interaction for hCG have the same function in human follicle-stimulating hormone (hFSH). Wild type or mutant alpha-subunit cDNAs were coexpressed with wild type hFSH or hCG beta cDNA in sialylation defective Chinese hamster ovary cells. Recombinant hormones were tested in a radioligand receptor competition assay, using rat testis membranes as a source of FSH and LH receptors. Mutant hFSH heterodimers F33A-FSH, R35A-FSH, Arg42-Ser43-Lys44/Ala42-Ala43-Ala44- FSH all displaced 125I-hFSH in a similar fashion, indicating that these residues are not important for binding of hFSH to the rat FSH receptor. On the other hand, F33A-CG evidenced a 5-fold decrease in binding, while R35A-CG had over a 100-fold decrease in binding to the rat LH receptor when compared to the wild type recombinant hCG. These data demonstrate that a receptor-binding site on the common alpha-subunit which is very important for hCG binding to LH receptor is not important for the binding of hFSH to FSH receptor. Our interpretation of these findings is that there are fundamental structural differences in the receptor interface contacts of the common alpha-subunit, which stabilize receptor binding among members of the glycoprotein hormone family.

The flanking amino acids of the human follitropin beta-subunit 33-53 region are involved in assembly of the follitropin heterodimer

Previous analyses of the topology of human follitropin (hFSH) with monoclonal antibodies and antipeptide antibodies have led to a current operating hypothesis that some amino acids within the hFSH beta 33-53 region are surface oriented, and others participate in subunit contact. Protein structural analysis predicts beta-turns within this region, and the immunochemical studies indicate that the ends may be involved in subunit contact. In this study, hFSH beta was mutagenized to change 34TRDL37 to 34AAAA37 or 48QKTCT52 to 48AAACA52, allowing us to study the ends of the hFSH beta 33-53 sequence contiguous with the hFSH beta sequence. Wild-type and mutant cDNAs were coexpressed with alpha-subunit cDNA in CHOPro-5 cells. Wild-type hFSH was secreted from cells cotransfected with wild-type hFSH alpha and hFSH beta cDNAs, as expected. However, heterodimeric hFSH was minimally detected in the medium from cells transfected with the 34TRDL37 mutant and was not detected in the case of the 48QKTCT52 mutant. Analysis of cell lysates (intracellular FSH) by immunoprecipitation and polyacrylamide gel electrophoresis showed that wild-type and mutant beta-subunits were indistinguishable and recoverable intact from each cell line. Additionally, analysis of lysates with a conformation-specific monoclonal antibody 3G3 revealed that similar levels of properly folded beta-subunit were produced in cells expressing wild-type or either mutated beta-subunit. These data indicate that the flanking amino acids of the hFSH beta 33-53 region, in particular 48QKTCT52, are critical for assembly of hFSH heterodimer.

Estrogen-stimulation of postconfluent cell accumulation and foci formation of human MCF-7 breast cancer cells

Foci, nodules of cellular overgrowth, that appear after confluence are an in vitro characteristic of malignant transformation. A well-studied in vitro model of estrogen-dependent tumors is the MCF-7 cell line, derived from a pleural metastasis of a human breast adenocarcinoma. We report that cultivation of MCF-7 cells, using routine methods, results in extensive estrogen-stimulated postconfluent cell accumulation characterized by discrete three-dimensional arrays. Side view Nomarski optical sections revealed these to be principally multicellular foci with occasional domes and pseudoacinar vacuoles. This effect on MCF-7 cell growth occurs in media containing fetal bovine serum but not with calf serum or charcoal-dextran-treated fetal bovine serum unless supplemented with estrogens. Foci formation starts 5-6 days after confluence, and the number of foci generated is a function of the concentration of added estrogens. Foci formation is suppressed by the antiestrogens Tamoxifen and LY 156758. Addition of progesterone, testosterone, or dexamethasone had little or no effect, while various estrogens (ethinyl estradiol, diethylstilbestrol, and moxestrol) induced foci development. Clones derived from single cells of the initial MCF-7 population revealed a wide variance in estrogen-induced foci formation, demonstrating heterogeneity of this tumor cell line. The postconfluent cell growth of the estrogen receptor-deficient cell line, MDA-MB-231, contrasted with MCF-7 by developing an extensive multilayer morphology devoid of discrete structures. The tumorigenic potential of the MCF-7 cells used in our experiments was confirmed by their estrogen-dependent growth in immunosuppressed male BDF1 mice. These data suggest an estrogen receptor-based mechanism for the development of multicellular foci during postconfluent growth of MCF-7 cells. After confluence, foci, in contrast to the quiescent surrounding monolayer, retain proliferating cells. Focus formation, therefore, reflects the heterogeneous responsiveness of these cells to estrogens and should provide a model permitting in vitro comparisons between the progenitor cells of multicellular foci and the monolayer population.

Flexible-substratum technique for viewing cells from the side: some in vivo properties of primary (9+0) cilia in cultured kidney epithelia

Cells cultured on thin plastic (e.g. Formvar, Teflon, polycarbonate) membranes can be clearly imaged from the side in vivo by video microscopy. We have used this flexible-substratum technique to examine the behaviour and properties of primary cilia in confluent cultures of the kidney epithelial cell lines PtK1, PtK2, LLC-PK1, MDCK and BSC-40. In these cells primary cilia appear as rigid rods, up to 55 micron long, which project at various angles from the dorsal cell surface. The length distribution of primary cilia in confluent cultures is a distinct characteristic of each established kidney cell line examined, with LLC-PK1 exhibiting three distinct length populations. Primary cilia of kidney cell lines bend passively in response to flow but do not display propagated bending or vortical motions. Up to 26% of the cilia in the cell types examined possess one or more conspicuous swellings along the ciliary shaft. Treatment with 0.05% trypsin, which is sufficient to cause cell rounding, does not induce the resorption or shedding of the cilium. These direct observations demonstrate that kidney epithelial-cell primary cilia are non-motile and longer than previously thought, and suggest that their length represents a phenotypic marker for each cell line.