Biodegradable implants for Pipkin fractures.

Axel Prokop; Hanns-Joachim Helling; Ulrich Hahn; Chira Udomkaewkanjana; Klaus Emil Rehm

doi:10.1097/01.blo.0000150374.46728.54

Home/Archive/PubMed

PubMed · 15738826

Biodegradable implants for Pipkin fractures.

Axel Prokop·Hanns-Joachim Helling·Ulrich Hahn·Chira Udomkaewkanjana·Klaus Emil Rehm

View original source ↗Export metadata ↓

Abstract

The current study was designed to clarify whether biodegradable poly-L/DL lactide pins provide an operative alternative for fixation of Pipkin fractures. Nine patients with Pipkin fractures (one with Pipkin Type I, one with Pipkin Type II, and seven with Pipkin Type IV fractures) were treated surgically between 1996 and 2002. In all patients, the femoral head fractures were fixed with biodegradable, 2.7-mm and 2.0-mm polylactide pins. Eight patients were followed up for an average of 54.2 months. One patient died before the final followup. Eight fractures healed uneventfully. In one patient, a persisting femoral head defect led to posttraumatic arthritis requiring insertion of a femoral endoprosthesis at 1 year. The average range of motion of the affected hips of all patients at followup was 109 degrees -0 degrees -0 degrees in flexion and extension. External and internal rotation averaged 37 degrees -0 degrees -29 degrees . One patient had Brooker Grade I heterotopic ossification develop, and another had a Grade II heterotopic develop. Merle d'Aubigne and Postel ratings showed two excellent and five satisfactory results (average score, 13.1). Adverse effects from the polylactide implants were not observed. Pipkin fractures can be fixed successfully with biodegradable polylactide pins.

Explore related subjects

Absorbable Implants Adult Bone Nails Female Femoral Fractures Follow-Up Studies Fracture Fixation, Internal Fracture Healing Humans Male Middle Aged Patient Satisfaction Radiography Range of Motion, Articular Treatment Outcome Clinical Trial Journal Article Research Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Axel Prokop, Hanns-Joachim Helling, Ulrich Hahn, Chira Udomkaewkanjana, Klaus Emil Rehm. 2005. Biodegradable implants for Pipkin fractures.. https://doi.org/10.1097/01.blo.0000150374.46728.54

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Encapsulation of proteins in biodegradable polymeric microparticles using electrospray in the Taylor cone-jet mode.

Solvent extraction (or evaporation from a W(1)/O/W(2)-dispersion), coacervation, and spray drying methods are commonly employed to encapsulate protein drugs in polymeric microparticles for sustained delivery applications. To overcome the limitations of these methods, a novel electrospray method was developed to encapsulate a model protein drug-bovine serum albumin (BSA) in biodegradable polymeric microparticles and examine the feasibility of the process in not denaturing the protein. Microparticles of approximately 20 microm diameter with corrugated surfaces and smooth surfaces were observed by scanning electron microscope. Confocal laser scanning microscope images showed that BSA was distributed evenly in microparticles. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was employed to investigate the protein integrity of BSA released from the polymer matrix after 38 days. No protein degradation was observed during the 38 days release. The secondary structure of released BSA was characterized by Fourier transform infrared (FTIR) and circular dichroism (CD), which suggested that the released BSA was almost identical to native BSA. The encapsulation efficiency could reach 76% by adjusting the amount of the additive Pluronic F127 and processing parameters. The release profile could be tailored by the fabrication process and the sustained release of BSA could endure for more than 1 month. More than 80% of the bioactivity of BSA (evaluated by BSA ELISA kit) could be maintained after releasing from polymer matrix. Findings of the present study demonstrate that this novel electrospray method is a promising approach to encapsulate bioactive materials such as proteins, enzymes, antibiotics, and DNA fragments in biodegradable polymeric particles.

Absorbable Implants↗

PubMed2007

A novel poly(ethylene glycol)-fibrinogen hydrogel for tibial segmental defect repair in a rat model.

The aim of this study is to investigate regeneration in a segmental bone defect using a novel fibrinogen-based hydrogel material. The use of hydrogels made from poly(ethylene glycol) (PEG) conjugated to fibrinogen for this purpose may be better to conventional fibrin-based materials as it offers an additional degree of control over the structural characteristics and biodegradation of the material. At the same time, it maintains some of the inherent biofunctionality of the fibrinogen molecule. PEGylated fibrinogen hydrogels with various degrees of proteolytic resistance based on PEG and fibrinogen composition were designed for slow, intermediate, and fast biodegradation. The hydrogels were implanted into 7-mm segmental rat tibial defects without additional osteoinductive factors with the rationale that the ingrowth matrix will displace the normal fibrin clot while sustaining a similar healing effect for a longer duration. Histological and X-ray results confirmed that the extent and distribution of newly formed bone in the defect after 5 weeks strongly parallels the biodegradation pattern of the implanted material. When compared to nonunions in animals treated with the fast-degrading implants and untreated control animals, the rats implanted with the intermediate-degrading material exhibited osteoneogenesis. This data supports the hypothesis that the perseverance of the PEGylated fibrinogen material can be synchronized with the optimal healing characteristics of a segmental osseous defect and that the consequent sustained release of fibrinogen fragments facilitates the osteogenic response at the injury site. The PEGylated fibrinogen material may, therefore, be a highly efficacious material for promoting the healing of bone defects and especially nonunion fractures.

Absorbable Implants↗

PubMed2007

Pores in synthetic nerve conduits are beneficial to regeneration.

Current opinion holds that pores in synthetic nerve guides facilitate nerve regeneration. Solid factual support for this opinion, however, is absent; most of the relevant studies assessed only morphological parameters and results have been contradictory. To evaluate the effect of pores, the rat sciatic nerve was either autografted or grafted with nonporous, macroporous (10-230 mum), and microporous (1-10 microm) biodegradable epsilon-caprolactone grafts. Twelve weeks later, the grafted nerves were resected, and the electrophysiological properties were determined in vitro. Subsequently midgraft-level sections were inspected, and peroneal nerve sections were evaluated morphometrically. Finally, the gastrocnemic and tibial muscle morphometrical properties were quantified. The microporous nerve graft performed much better than the nonporous and macroporous grafts with respect to most parameters: it was bridged by a free floating bundle that contained myelinated nerve fibers, there were more nerve fibers present distal to the graft, the electrophysiological response rate was higher, and the decrease in muscle cross-sectional area was markedly smaller. Hence, the present study demonstrates the beneficial effect of synthetic nerve guide pores on nerve regeneration, although with the caveat that not pores per se, but only small (1-10 microm) pores were effective.

Absorbable Implants↗