The use of biodegradable scaffold as an alternative to silicone implant arthroplasty for small joint reconstruction: An experimental study in minipigs

Development of novel hybrid 3D-printed degradable artificial joints incorporating electrospun pharmaceutical- and growth factor-loaded nanofibers for small joint reconstruction

Small joint reconstruction remains challenging and can lead to prosthesis-related complications, mainly due to the suboptimal performance of the silicone materials used and adverse host reactions. In this study, we developed hybrid artificial joints using three-dimensional printing (3D printing) for polycaprolactone (PCL) and incorporated electrospun nanofibers loaded with drugs and biomolecules for small joint reconstruction. We evaluated the mechanical properties of the degradable joints and the drug discharge patterns of the nanofibers. Empirical data revealed that the 3D-printed PCL joints exhibited good mechanical and fatigue properties. The drug-eluting nanofibers sustainedly released teicoplanin, ceftazidime, and ketorolac in vitro for over 30, 19, and 30 days, respectively. Furthermore, the nanofibers released high levels of bone morphogenetic protein-2 and connective tissue growth factors for over 30 days. An in vivo animal test demonstrated that nanofiber-loaded joints released high concentrations of antibiotics and analgesics in a rabbit model for 28 days. The animals in the drug-loaded degradable joint group showed greater activity counts than those in the surgery-only group. The experimental data suggest that degradable joints with sustained release of drugs and biomolecules may be utilized in small joint arthroplasty.

Primary trapeziectomy with Regjoint(TM), a poly-L/D-lactide spacer, a two-year follow-up study with new radiological assessment tool

The aim of this retrospective study was to evaluate the potential bony erosion and the clinical and radiological results of primary trapeziectomy with RegjointTM interposition, in patients with peritrapezial arthritis. Data were recorded on twenty patients over a period of two years (January 2015-December 2016). On average 24 months, patients were reconvened for a post-operative evaluation (subjective evaluation of pain, function and patient satisfaction; clinical evaluation with strength and mobility measures; post-operative X-rays). On X-rays, 2 criteria were evaluated: the bony erosion and the shortening of the thumb column (trapezium+metacarpal height measure, ratio between first and second metacarpal bones, a new radiological assessment tool based on a trapezoid relationship gradation). In most patients, surgery relieved pain and offered good functional results, according to the Quick Disabilities of the Arm, Shoulder and Hand scale. Following surgery, our patients showed a subjective improvement, both in terms of pain and functional results. For plain X-ray, only 3 patients showed an osteolytic lesion (maximum of 2.8 millimeters) on the first metacarpal base. A statistically significant reduction in the thumb column height was generally observed on follow-up X-rays. However, all of these radiologic changes were present without any clinical impact. We show that the RegjointTM spacer is an available alternative in the surgical treatment of peritrapezial arthritis. We did not highlight any significant associated complications, no important adverse tissue reaction or bone erosion, no pain or functional disorder. Type of study/level of evidence Therapeutic IV.

Pharmaceutical-eluting hybrid degradable hydrogel/microparticle loaded sacs for finger joint interpositional arthroplasty

Despite recent advances in medical technology, treatment of chronic osteomyelitis in the small joint of the hand remains challenging. Here, we exploited hybrid biodegradable hydrogel/microparticle/polycaprolactone (PCL) sacs for finger joint interpositional arthroplasty via electrospraying and rotational molding techniques. Degradable Pluronic F127, poly(lactic-co-glycolic acid) (PLGA), and PCL were starting materials for the hydrogels, microparticles, and sac, respectively. Vancomycin, ceftazidime, and lidocaine were the embedded pharmaceuticals. The in vitro and in vivo drug release behaviors of hybrid drug-eluting sacs were assessed. The empirical outcomes show that the size distribution of the electrosprayed vancomycin/ceftazidime/lidocaine PLGA microparticles was 8.25 ± 3.35 μm. Biodegradable PCL sacs offered sustainable and effective release of vancomycin, ceftazidime, and lidocaine, respectively, after 30, 16, and 11 days in vitro. The sacs also discharged high levels of anti-microbial agents for 56 days and analgesics for 14 days in a rabbit knee joint model. The blood urea nitrogen (creatinine) levels remained normal at various time points: 16.5 ± 2.5 mg/dL (0.85 ± 0.24 mg/dL), 20.0 ± 1.4 mg/dL (1.0 ± 0.16 mg/dL), 19.3 ± 2.4 mg/dL (1.13 ± 0.15 mg/dL), and 20.0 ± 2.16 mg/dL (1.0 ± 0.16 mg/dL) at days 7, 14, 21, and 35, respectively. The empirical outcomes of this study suggested that the hybrid biodegradable drug-eluting sacs with extended liberation of pharmaceuticals may find applications in the small joints for post-operative pain relief and infection control.

Basal joint arthroscopy indications in first CMC joint arthritis

Basal joint arthroscopy is one of the more recent evolutions of small joint arthroscopy in upper limb surgery. Conventional arthroscopy equipment is generally sufficient to perform these procedures without any specific adaptation. Arthroscopic exploration of the trapeziometacarpal joint is performed through 1R, 1U portals with the addition of a thenar portal in some indications. In the context of basal joint arthritis, we can distinguish diagnostic, preventive and therapeutic indications for arthroscopy. Diagnostic indications are the assessment of painful post-traumatic basal joint lesions of cartilage and ligaments, and the evaluation of chondromalacia and ligament attenuation to help classify basal joint osteoarthritis to provide additional clinical information, which can influence further treatment depending on the stage of the disease. Preventive indications are reduction of Bennett's fracture, basal joint dislocation management to avoid post-traumatic instability and chondromalacia; it can also be indicated after decompensation of hyperlaxity. Therapeutic indications are debridement, ligament augmentation procedures or shrinkage ± interposition ± partial or total trapeziectomy, ligamentoplasty, etc. Basal joint arthroscopy appears to be the seat of advances in arthroscopic procedures with clinical results at least as effective as classical open surgery, but this technique still requires long-term evaluation.

Unfavourable early outcomes of total trapeziectomy with RegJoint™ interposition: a report of 38 osteoarthritic hands in 34 patients

This retrospective study analysed the results of total trapeziectomy with RegJoint™ interposition in 38 osteoarthritic hands in 34 patients. Patients were evaluated preoperatively, at follow-up visits, and at a mean final follow-up of 33 months (range 20-53) with plain radiographs, computed tomography, as well as with subjective and objective evaluations. Pain decreased and subjective outcomes and function improved significantly. Computed tomography 18 months after operation showed osteolysis in 24 cases. Three patients developed wrist pain 12-18 months after operation with MRI findings of a foreign-body reaction in each case. One of these patients was scheduled for revision surgery. Although the clinical results were satisfactory, the risk of foreign-body reaction and osteolysis is noteworthy. We conclude that the use of RegJoint™ should be reconsidered since the implant probably offers no benefit in the treatment of trapeziometacarpal osteoarthritis. Level of evidence: IV.

Interpositional Arthroplasty of the First Metatarsophalangeal Joint with Bioresorbable Pldla Implant in the Treatment of Hallux Rigidus and Arthritic Hallux Valgus: A 9-Year Case Series Follow-Up

BACKGROUND AND AIMS

The interpositional arthroplasty was developed to retain foot function and to relieve pain due to the arthritis of the first metatarsophalangeal joint. The bioabsorbable poly-L-D-lactic acid RegJoint^® interpositional implant provides temporary support to the joint, and the implant is subsequently replaced by the patient's own tissue. In this study, we retrospectively examined the results of the poly-L-D-lactic acid interpositional arthroplasty in a 9-year follow-up study among patients with hallux valgus with end-stage arthrosis or hallux rigidus.

MATERIAL AND METHODS

Eighteen patients and 21 joints underwent interpositional arthroplasty using the poly-L-D-lactic acid implant between February 1997 and October 2002 at Tampere University Hospital. Of these, 15 (83.3%) (21 joints) patients were compliant with clinical examination and radiographic examination in long-term (average 9.4 years) follow-up. The mean age of the patients was 48.3 (from 28 to 67) years at the time of the operation. Six patients underwent the operation due to arthritic hallux valgus and nine patients due to hallux rigidus.

RESULTS

The mean Ankle Society Hallux Metatarsophalangeal-Interphalangeal Scale and visual analogue scale (VAS) for pain scores improved after the operation in all patients. The decrease of pain (visual analogue scale) after the operation was statistically significant (77.5 vs 10.0; p < 0.001). Postoperative complications were observed in 3 (14.3%) joints of two hallux rigidus patients. For these patients, surgery had only temporarily relieved the pain, and they underwent reoperation with arthrodesis.

CONCLUSION

In conclusion, interpositional arthroplasty using a poly-L-D-lactic acid implant yielded good results. This study indicates that the poly-L-D-lactic acid interpositional implant may be a good alternative for arthrodesis for treatment of end-stage degeneration of the first metatarsophalangeal joint.

Bioabsorbable poly-L/D-lactide (96/4) scaffold arthroplasty (RegJoint™) for trapeziometacarpal osteoarthritis: a 3-year follow-up study

The poly-L/D-lactide joint scaffold (RegJoint™) has recently been associated with adverse tissue reactions and osteolysis after partial trapeziectomy for trapeziometacarpal osteoarthritis. Twenty-two of 23 patients previously operated on with this scaffold were re-examined at a mean follow-up of 3.3 years (range 36-53 months). Overall, the results showed an unacceptably high rate of adverse tissue reactions related to the degradation process of the implant, resulting in a revision procedure in three patients. At final follow-up, at which point the implant had completely degraded, there were no signs of ongoing adverse tissue reactions. There was a significant decrease in pain, increase in strength and subjective improvement in function at final follow-up compared with the pre-operative results in patients who had not undergone revision surgery. However, owing to the high incidence of adverse tissue reactions, the use of the implant has been discontinued in the treatment of trapeziometacarpal osteoarthritis.

LEVEL OF EVIDENCE

IV.

Unfavourable short-term outcomes of a poly-L/D-lactide scaffold for thumb trapeziometacarpal arthroplasty

The bioabsorbable poly-L-D-lactide joint scaffold arthroplasty is a recent attempt in the reconstruction of small joints in rheumatoid patients. In this study, we analysed the 1-year clinical, functional and radiologic results of partial trapeziectomy with the poly-L-D-lactide (96/4) joint scaffold in 23 patients with isolated trapeziometacarpal osteoarthritis. The results showed that the procedure provided pain relief and improvement in overall function according to the Quick Disabilities of the Arm, Shoulder and Hand score in most patients. However, radiographs demonstrated a high frequency of osteolysis around the implant. Seven patients developed clinically manifested foreign-body reactions 6 months to 1 year after surgery. The reason for the unexpected tissue reactions may relate to excessive mechanical cyclic loading of the implant. The outcomes of this implant in our patients have not been sufficiently beneficial and we have discontinued use of this implant in isolated trapeziometacarpal osteoarthritis.

Textile cell-free scaffolds for in situ tissue engineering applications

In this article, the benefits offered by micro-fibrous scaffold architectures fabricated by textile manufacturing techniques are discussed: How can established and novel fiber-processing techniques be exploited in order to generate templates matching the demands of the target cell niche? The problems related to the development of biomaterial fibers (especially from nature-derived materials) ready for textile manufacturing are addressed. Attention is also paid on how biological cues may be incorporated into micro-fibrous scaffold architectures by hybrid manufacturing approaches (e.g. nanofiber or hydrogel functionalization). After a critical review of exemplary recent research works on cell-free fiber based scaffolds for in situ TE, including clinical studies, we conclude that in order to make use of the whole range of favors which may be provided by engineered fibrous scaffold systems, there are four main issues which need to be addressed: (1) Logical combination of manufacturing techniques and materials. (2) Biomaterial fiber development. (3) Adaption of textile manufacturing techniques to the demands of scaffolds for regenerative medicine. (4) Incorporation of biological cues (e.g. stem cell homing factors).

Knitted polylactide 96/4 L/D structures and scaffolds for tissue engineering: shelf life, in vitro and in vivo studies

This study covers the whole production cycle, from biodegradable polymer processing to an in vivo tissue engineered construct. Six different biodegradable polylactide 96/4 L/D single jersey knits were manufactured using either four or eight multifilament fiber batches. The properties of those were studied in vitro for 42 weeks and in 0- to 3-year shelf life studies. Three types (Ø 12, 15 and 19 mm) of cylindrical scaffolds were manufactured from the knit, and the properties of those were studied in vitro for 48 weeks. For the Ø 15 mm scaffold type, mechanical properties were also studied in a one-year in vivo experiment. The scaffolds were implanted in the rat subcutis. All the scaffolds were γ-irradiated prior to the studies. In vitro, all the knits lost 99% of their mechanical strength in 30 weeks. In the three-year follow up of shelf life properties, there was no decrease in the mechanical properties due to the storage time and only a 12% decrease in molecular weight. The in vitro and in vivo scaffolds lost their mechanical properties after 1 week. In the case of the in vivo samples, the mechanical properties were restored again, stepwise, by the presence of growing/maturing tissue between weeks 3 and 12. Faster degradation was observed with in vitro scaffolds compared to in vivo scaffolds during the one-year follow up.

The Mean Seven Years' Results of the Use of Poly-L/D-Lactic Acid (PLDLA) Interposition Implant and Bone Packing in Revision Metacarpophalangeal Arthroplasty: A Prospective Cohort Study

Background and Aims:

Revision arthroplasty of metacarpophalangeal (MCP) joints in chronic inflammatory arthritis patients after silicone implants is challenging due of severe bone loss and soft tissue deficiencies. The aim of this study was to evaluate the outcome of revision MC Parthroplasty using poly-L/D-lactic acid 96:4 (PLDLA) interposition implant and morcelised allograft or autograft bone packing in patients with failed MCP arthroplasties and severe osteolysis.

Material and Methods:

The study group consisted of 15 patients (15 hands and 36 joints) at a mean follow-up of seven years (range 5–10 years). The radiographs were reviewed for osteolysis and incorporation of the grafted bone. The clinical assessments included active range of motion, evaluation of pain, subjective outcome and assessment of grip power.

Results:

PLDLA interposition arthroplasty combined with bone packing provided satisfactory pain relief, but function was limited. Radiographic analysis showed complete incorporation of the grafted bone to the diaphyseal portion of the host metacarpal and phalangeal bones in 30 of the 36 joints. All the patients had very limited grip strength, both on the operated and non-operated side.

Conclusions:

Due to soft tissue deficiencies long-term function and alignment problems can not be resolved with PLDLA interposition implant.

Structure-process-functional property relationship of nanostructured carbon mediated cellular response for soft-tissue reconstruction and replacement

The flexible and ductile silicone is widely used as a soft-tissue substitute for joint reconstruction and replacement in situations including joint pain and loss of mobility caused by the congenital or acquired factors such as osteoarthritis. Although these artificial devices have an expected life span of 15 years or more, they can fragment prematurely. Explanations for such failure are low tensile strength and inadequate bone build-up around the device, as a result of which the device does not bind with the surrounding tissues. Thus, the continued challenge for materials in contact with the bone is the design of high-strength-at-break silicone with the ability to modulate cell-substrate interactions for promoting osseointegration and long-term stability. To this end, we have discovered exciting evidence that the introduction of a novel nanostructured carbon in the void space between the silicone chains combined with processing at elevated pressure favorably stimulate cellular functions and provide a high degree of cytocompatibility. Furthermore, the high strength-at-break and undiminished intrinsic elongation of silicone are retained. In this regard, we combine here materials science and engineering and cellular biology, to elucidate the mechanism of cell-substrate interactions and the molecular machinery controlling the cell response. This is accomplished by investigating cell attachment, proliferation, and morphology, including cytomorphometric evaluation and quantitative assessment of prominent proteins, actin, vinculin, and fibronectin that are sensitive to cell-substrate interactions. The study strengthens the foundation for utilizing the nano- or quantum-size effects of nanostructured biomaterials.

Degradable nitric oxide-releasing biomaterials via post-polymerization functionalization of cross-linked polyesters

The synthesis of diverse nitric oxide (NO)-releasing network polyesters is described. The melt phase condensation of polyols with a calculated excess of diacid followed by thermal curing generates cross-linked polyesters containing acid end groups. Varying the composition and curing temperatures of the polyesters resulted in materials with tunable thermal and degradation properties. Glass transition temperatures for the synthesized materials range from -25.5 to 3.2 °C, while complete degradation of these polyesters occurs within a minimum of nine weeks under physiological conditions (pH 7.4, 37 °C). Post-polymerization coupling of aminothiols to terminal carboxylic acids generate thiol-containing polyesters, with thermal and degradation characteristics similar to those of the parent polyesters. After nitrosation, these materials are capable of releasing up to 0.81 μmol NO cm(-2) for up to 6 d. The utility of the polyesters as antibacterial biomaterials was indicated by an 80% reduction of Pseudomonas aeruginosa adhesion compared to unmodified controls.

Bioreconstructive poly-L/D-lactide implant compared with Swanson prosthesis in metacarpophalangeal joint arthroplasty in rheumatoid patients: a randomized clinical trial

It was hypothesized that the bioresorbable interposition implant might offer a viable alternative to conventional silicone implant arthroplasty in rheumatoid metacarpophalangeal joint destruction. A randomized clinical study was performed to compare a stemless poly-L/D-lactide copolymer 96 : 4 (PLDLA) implant with the Swanson silicone implant. Results in 52 patients (53 hands and 175 joints) at a mean follow-up of 2 years (minimum 1 year) showed that the improvement in clinical assessments was comparable in both groups, except for better maintenance of palmar alignment in the Swanson group. The lack of implant fractures and intramedullary osteolysis were advantages of the PLDLA implant. The bioresorbable PLDLA interposition implant may offer an alternative tool for tailored reconstruction of rheumatoid metacarpophalangeal joints.

Comparison of bioreplaceable interposition arthroplasty with metatarsal head resection of the rheumatoid forefoot

BACKGROUND

Interposition arthroplasty with bioreplaceable poly-L/D-lactic acid (PLDLA) implants has been studied in Finland with promising results in reconstruction of the rheumatoid hand. We evaluated this material in a series of patients with rheumatoid forefoot deformities.

MATERIALS AND METHODS

Thirty-five patients were randomized to either PLDLA metatarsophalangeal joint interposition arthroplasty group (16 patients) or to conventional metatarsal head resection group (19 patients).

RESULTS

At 3 months after surgery, the function VAS was significantly better in the control group (p = 0.003). The difference disappeared by 12 months. Otherwise, comparison between the two groups did not reveal any statistically significant differences in the AOFAS scores or the pain VAS at 3 or 12 months.

CONCLUSION

Early results after PLDLA interposition arthroplasty of metatarsophalangeal joints were not as promising as previously reported with rheumatoid metacarpophalangeal reconstruction.

A midterm follow-up study of bioreconstructive polylactide scaffold implants in metacarpophalangeal joint arthroplasty in rheumatoid arthritis patients

This paper presents the results of a prospective study of 80 metacarpophalangeal joint arthroplasties, in which biodegradable polylactide 96/4 copolymer scaffolds were used. Twenty-three rheumatoid arthritis patients were assessed at an average of 59 months after operation, which exceeds the resorption time of P(L/D)LA 96/4 according to animal experiments. Palmar subluxation exceeded half of the bone thickness in 39 joints before operation and in nine at the last follow-up. Ulnar deviation decreased from 25 degrees to 5 degrees , extension deficit from 32 degrees to 15 degrees and active flexion from 76 degrees to 63 degrees . The results are comparable with published data on silicone implant arthroplasties. Implant resorption did not induce any significant osteolysis in the medium term and the restoration of the structure and function of the hand was maintained after implant resorption, probably as the guided fibrous tissues had replaced the dissolved implant.