Restoring independency with an osteochondral graft of the navicular for coronoid process reconstruction.

INTRODUCTION: The coronoid is a crucial element for elbow stability. In case of posttraumatic instability or reduced range of motion, a complex reconstruction might be necessary. CASE: We present the case of a polytraumatized patient with complex upper extremity injury and initial poor outcome. Subluxation after initial surgery was treated by sublime tubercle reconstruction with a corticocancellous iliac crest graft. Due to massive ossification, the elbow remained stiff and the paraplegic patient was unable to use a manually propelled wheelchair. After arthrolysis, the unstable elbow was treated with an osteocartilaginous graft from the navicular of the foot as well as ulnar and radial collateral ligamentoplasties. At the time of follow-up, the patient had a stable joint and was able to independently perform activities of daily living. CONCLUSION: An autologous navicular graft seems to be an excellent option for our paraplegic patient as the shape matches the sublime tubercle of the ulna.

Morphological changes in the human cervical intervertebral disc post trauma: response to fracture-type and degeneration grade over time.

PURPOSE: In the first 24 h post-intervertebral disc (IVD) trauma, up to 75 % cell death has been reported. In addition, burst fractures cause post-traumatic disc degeneration by elevated pro-apoptotic and pro-inflammatory gene transcription. Moreover, some patients have pre-trauma degenerative disc disease. The aim of the study was to assess histological changes and cell-death over a time period of up to 1 year caused by mechanical and structural factors. METHODS: 116 anterior portions of IVDs of the cervical spine were studied histologically by light microscopy and ultrastructurally by transmission electron microscopy (TEM). The group was investigated with regard to three main parameters: fracture mechanism (compressive vs. tensile/shear loads), degeneration grade (low vs. high) and endplate fracture (with vs. without). Disc architecture (e.g. ruptures) was studied histologically. Cell morphology was examined ultrastructurally to quantify cell-death, healthy and balloon cells. According to ultrastructural observations, two time-groups (up to 6 days vs. later) were established. Statistical analyses were carried out within and between time-groups. RESULTS: Histological changes were obvious in the annulus fibrosus where ruptures with haematoma were replaced by granulation tissue. Significant differences in cell-death were seen in the first few days due to different loads. In contrast to the more degenerated segments, low degenerated ones revealed significantly less cell death with time post-trauma. Interestingly, no difference was found between groups after the sixth day. Cell-death (mean 44 % for all investigated groups) remained high after day 6 post-trauma. CONCLUSION: IVDs retrieved from low grade degenerated segments revealed a significant recovery, with less cell-death and a partially restored disc matrix, although cell-death remained high. Long-term clinical studies of stabilized segments arising from different fracture mechanisms are required.

Morphological changes in disc herniation in the lower cervical spine: an ultrastructural study.

INTRODUCTION: The basis of disc degeneration is still unknown, but is believed to be a cell-mediated process. Apoptosis might play a major role in degenerative disc disease (DDD). The aim of this study was to correlate the viability of disc cells with the radiological degeneration grades (rDG) in disc herniation. MATERIALS AND METHODS: Forty anterior IVD's (C4-C7) from 39 patients with DDD were studied histologically and ultrastructurally to quantify healthy, "balloon", chondroptotic, apoptotic and necrotic cells. Patients were classified to their rDG, as having either prolapse (P: DGII + III) and/or osteochondrosis (O: DGIV + V). Similar studies were undertaken on eight control discs. RESULTS: Cell death by necrosis (mean 35%) was common but differed not significantly in both groups. All patients with a disc prolapse DGII + III revealed balloon cells (iAF: mean 32%). All appeared alive and sometimes were hypertrophic. However, significantly less balloon cells were found in the O-Group. Control samples revealed no evidence of "balloon" cells in DGII and only a minor rate in DGIII. CONCLUSION: According to the different rDG, quantitative changes were obvious in healthy and "balloon" cells, but not for cell death. At the moment it can only be hypothesized if "balloon" cells are part of a repair strategy and/or cause of disc herniation.

The metaphyseal bone defect in distal radius fractures and its implication on trabecular remodeling-a histomorphometric study (case series).

BACKGROUND: The invention of the locking plate technology leads to alterations of treatment strategies at metaphyseal fracture sites with the concept of spontaneous remodeling of trabecular bone voids. Whereas trabecular regeneration has been proven in experimental animal studies, no histologic data exist on human fracture healing with special emphasis on bone voids. METHODS: In order to qualify the trabecular bone remodeling capacity in vivo, bone specimens from the metaphyseal bone void were analyzed 14 months after trauma using quantitative histomorphometry. Twenty-five patients with an unstable dorsally displaced distal radius fracture were fixed with a palmar locking plate without additional bone graft or substitute. At implant removal, specimens from the previous compression void were harvested with a trephine in a volar-dorsal direction. In 16 patients, histomorphometric analysis could be performed, comparing the dorsal trabecular network with the volar, non-compressed ultrastructure. RESULTS: Significant differences for bone volume/total volume (BV/TV), trabecular number (TbN) and trabecular separation (TbSp), but not for trabecular thickness (TbTh) and osteoid volume/total volume (OV/TV), were detected. Neither patient age, defect size nor gender had a significant influence on bone remodeling. CONCLUSIONS: The results of this study indicate that trabecular bone remodeling does not lead to pre-trauma bone quality in metaphyseal bone compression voids following reduction and application of a locking plate.

Morphological similarities after compression trauma of bovine and human intervertebral discs: Do disc cells have a chance of surviving?

To study the behavior of bovine disc cells and changes in disc matrix following in vitro compression tests; to compare the findings to investigations on human intervertebral discs (IVD) after burst fracture of the cervical spine. Healthy IVDs (n = 21) from three bovine tails were studied at 6 and 12 h post-mortem, with 16 IVDs subjected to impact loading and five as unloaded controls. IVDs (n = 8) from patients with burst fractures were compared to the bovine compression group. Specimens were studied macroscopically, histologically, and ultrastructurally for healthy cells, balloon cells, and disc cell death (DCD). Annulus ruptures were seen in both post-trauma groups, with radial ruptures being present histologically in all loaded bovine discs. Balloon cells were found in some human IVDs and were induced in vitro in bovine loaded discs within a distinct range of absorbed energy. There was a positive correlation between DCD and absorbed energy in all compartments of bovine discs. Both species showed similar patterns of DCD in the different compartments. This study was able to show similarities between both species in cell morphologies and matrix damage. The survival of the disc after substantial compression trauma thus seems to remain highly questionable.

Morphological differences in adolescent idiopathic scoliosis: a histological and ultrastructural investigation.

STUDY DESIGN: Histological and ultrastructural evaluation of cell morphologies at the concave and convex side of apical intervertebral discs (IVD) of adolescent idiopathic scoliosis (AIS). OBJECTIVE: To determine changes in cell morphology, viability, and cell death after asymmetric disc loading in AIS and to compare the findings with the tilt angles. SUMMARY OF BACKGROUND DATA: The reaction of cells to loading stimuli in the IVD seems to be specific. Although dynamic loads are more beneficial to the disc cells and maintain the matrix biosynthesis, static compressive loads suppress gene expression. METHODS: Apical IVDs (Th8-Th9 to L1-L2) from 10 patients with AIS were studied histologically (including TUNEL [TdT-mediated dUTP-biotin nick end labeling] staining to identify disc cell death by apoptosis) and ultrastructurally for matrix evaluations and to quantify healthy, balloon, chondroptotic, apoptotic, and necrotic cells on the concave and convex sides. Patients' spines were classified according to the Lenke classification. Degeneration was assessed according to the Pfirrmann grading system. Two groups were established; group 1 (G1) with a tilt of 5° to 9° and group 2 (G2) with a tilt of 10° to 19°. RESULTS: Balloon cells were found in significantly higher numbers at the concave side (G1-annulus fibrosus [AF]: mean 16%), with almost none found at the convex side. Mean numbers of healthy cells did not show differences comparing both sides. Significantly higher numbers of healthy cells were found with increasing tilt angle at the concave side. Necrosis (mean, 47%) increased toward the center of the disc but did not differ between the sides of the IVDs. The fibrils found in the outer AF on the convex side were 30% thinner. CONCLUSION: This study was able to show significant differences in cell morphologies in the AF on both sides and in correlation to the different tilt angles. The type and magnitude of load seem to influence disc cells. Further studies are required to provide more information on disc and cell changes in scoliosis.

Behaviour of ChronOS™ Inject in metaphyseal bone defects of distal radius fractures: tissue reaction after 6-15 months.

Biodegradable calcium phosphate cements are frequently used in human patients but data regarding resorption characteristic of ChronOS™ Inject in metaphyseal bone defects are lacking. Six patients (range 62-81 years) with a dorsally displaced distal radius fracture were treated with volar locking plate systems and ChronOS™ Inject application into the metaphyseal bone defect. During implant removal (time in situ 6-15 months, average 11 months) a 2mm diameter biopsy was obtained from the region of the previous cement injection. In all specimens' area of bone, osteoid and remaining tissue were histomorphometrically determined and presence of cement particles, bone marrow fibrosis and signs of inflammation were recorded. Vital bone tissue, osteoid formation, mast cell occurrence and marrow fibrosis were detected in most specimens. Varying but small amounts of granular material identified as remainder of the cement were detected in all specimens. Agglomerations of granular material were often surrounded by bone tissue and islets of newly formed osteoid in direct contact with the remaining cement also occurred. Bone density (i.e. area per region of interest) ranged between 6.9% and 36.2% and osteoid density between 0.5% and 7.8%. Bone osteoid ratio was higher in patients who received no osteoporosis medication and lower in patients who received osteoporosis medication (range 6.0-32.1). The present study shows that small amounts of ChronOS™ Inject are still detectable in human patients 15 months after implantation into a distal radius bone defect. During tissue remodelling ChronOS™ Inject is integrated into the newly formed trabecular bone meshwork.

Intervertebral disc cell death in the porcine and human injured cervical spine after trauma: a histological and ultrastructural study.

STUDY DESIGN: Histologic and ultrastructural study of disc cell death after traumatic injury to the human cervical spine and postmortem (p-m) in the porcine cervical spine. OBJECTIVE: To determine the changes in disc cell morphology, viability, and manner of cell death after trauma in human discs and p-m in porcine discs. SUMMARY OF BACKGROUND DATA: Similarities in the morphology of human and porcine spine have been shown in many histologic and biomechanical investigations. It is known that compressive or traumatic injuries to cartilage and intervertebral discs can result in cell death by necrosis or apoptosis. An additional form of apoptosis, chondroptosis, has been reported in articular cartilage, but not to date in the disc. METHODS: The anterior portion of intervertebral discs and endplates of 30 patients with traumatic injuries to the cervical spine were studied histologically (including trypan blue exclusion and TUNEL staining) and ultrastructurally. Fractures were classified according to Magerl and degeneration of the intervertebral disc according to Thompson and Benneker. Similar studies of disc and endplate were undertaken on porcine cervical spine 0 to 24 hours p-m. RESULTS: Electron and light microscopy showed up to 75% of human disc cells die within the first 24 hours of trauma, mainly by necrosis, similar to that seen in pig discs p-m. This study reports on 2 morphologies, chondroptosis and balloon cells, previously not described in the disc. Chondroptosis had been significantly higher and ballooned cells were exclusively seen in discs from fractures with compression, where apoptosis was also most common. Porcine samples revealed comparable rates of apoptosis and chondroptosis as fractures with less compression. Glycogen was commonly found in disc cells after trauma. CONCLUSION: Traumatic injuries of the human cervical spine lead to rapid changes in disc cell morphology and cell death, particularly via necrosis. The type of fracture and load seems to influence cell death.